トルマリン論文リスト（2002/08/08）
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九州大学の文献検索データベースinspecAで、tourmalineをキーワードにして検索した結果。大多数の研究は、誘電体や圧電素子としての利用の研究である。文献番号7、11、17だけが、トルマリンを水に入れて水質を変える話で、実質同じグループによって研究がなされている。トルマリンを水に入れて何か効果を期待するのは、日本特有の現象であることがわかる。
.f tourmaline
1: 120 document(s) found
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1/ 120
TI = The history of pyroelectricity: from ancient Greece to space missions
AU = Lang, S.B. (Dept. of Chem. Eng., Ben-Gurion Univ. of the Negev,
Beer-Sheva, Israel)
SO = Ferroelectrics (Switzerland), 99-108, vol.230, no.1-4, 1999
PU = Gordon & Breach
AB = Pyroelectrically was probably first observed by the Greeks more than 23
centuries ago. The philosopher Theophrastus wrote that lyngourion,
probably the mineral tourmaline, had the property of attracting straws
and bits of wood. For 2000 years, the peculiar properties of tourmaline
were more a part of mythology than of science. In the 18th Century,
pyroelectric studies made a major contribution to the development of our
understanding of electrostatics. In the 19th Century, research on
pyroelectricity added to our knowledge of mineralogy, thermodynamics and
crystal physics. Pyroelectricity gave birth to piezoelectricity in 1880
and to ferroelectricity in 1920. The field of pyroelectricity flourished
in the 20th Century with many applications, particularly in infrared
detection and thermal imaging. Pyroelectric sensors have been carried on
many space missions and have contributed significantly to our knowledge
of astronomy.
2/ 120
TI = Electrical response of piezoelectric materials under mechanical
excitation
AU = Ghosh, A.K., Munshi, T.K., Chakravorty, H.S. (Dept. of Phys., Kalna
Coll., Burdwan, India)
SO = J. Appl. Phys. (USA), 5753-6, vol.86, no.10, 15 Nov. 1999
PU = AIP
AB = The piezoelectric responses of different piezocrystals, rigidly backed,
have been studied under constant and impulsive stress. Equations
connecting electrical and mechanical interactions have been coupled to
find the response. The rates of growth and decay of piezovoltage have
been found to vary widely from material to material.
3/ 120
TI = Precise measurements of underwater explosion phenomena by pressure
sensor using fluoropolymer
AU = Murata, K., Takahashi, K., Kato, Y. (Res. & Dev. Dept., NOF Corp.,
Aichi, Japan)
SO = J. Mater. Process. Technol. (Switzerland), 39-42, vol.85, no.1-3, 1 Jan.
1999
PU = Elsevier
AB = To study underwater explosion phenomena, it is necessary to precisely
measure underwater shock wave and bubble pulse. Currently, underwater
shock wave is measured by pressure sensor, using tourmaline. However,
this method cannot sustain underwater shock pressure higher than 20 MPa.
To realize a pressure sensor which can sustain underwater shock pressure
higher than 100 MPa, we developed a pressure sensor using fluoropolymer
as the sensing element. Measurements of underwater shock wave profiles
were performed by pressure sensor using fluoropolymer and the results
were compared with those obtained using tourmaline. The experimental
results show that the sensor using fluoropolymer can precisely measure
underwater shock wave profiles in pressure ranges above 100 MPa. To
understand the destructive effects of underwater explosion phenomena, it
is necessary to accurately measure bubble pulse, as well as underwater
shock waves. Precise measurements of peak pressure and impulse of bubble
pulse, as well as underwater shock waves, were performed by pressure
sensor using fluoropolymer. The experimental results show that the peak
pressure of bubble pulse is about 15-30% of the peak pressure of the
shock wave, but the impulse of bubble pulse is about 1.5-2.5 times
bigger than that of shock wave, within the measured scaled distance
range. This is due to the fact that the duration of bubble pulse is
about ten times longer than that of shock wave.
4/ 120
TI = TOURMAL: software package for tourmaline, tourmaline-rich rocks and
related ore deposits
AU = Yavuz, F. (Istanbul Tech. Univ., Turkey)
SO = Comput. Geosci. (UK), 947-59, vol.23, no.9, Nov. 1997
PU = Elsevier
AB = TOURMAL is a user-friendly software package developed for editing,
storing, calculating and plotting microprobe tourmaline analyses from
different gel,logic environments such as granites and their related
aplites and pegmatites, metasomatic and vein type ore deposits,
stratabound base metal deposits, gold deposits, and sedimentary and
metamorphic rocks. Calculated results, saved in comma delimited ASCII
file format, permit the user to search for other applications related to
tourmaline compositions. The program prepares 28 binary and seven
ternary diagrams. It is written in Quickbasic for IBM PC and
compatibles, and runs under DOS and Windows operating systems with a VGA
graphic card. This program permits the user to convert standard binary
graphs and ternary diagrams into PCX file format for high quality
printouts.
5/ 120
TI = Influence of non-tetrahedral cations on Si-O vibrations in complex
silicates
AU = Mihailova, B., Gasharova, B., Konstantinov, L. (Central Lab. of Miner. &
Crystallogr., Bulgarian Acad. of Sci., Sofia, Bulgaria)
SO = J. Raman Spectrosc. (UK), 829-33, vol.27, no.11, Nov. 1996
PU = Wiley
AB = The effect of non-tetrahedral cations on the silicon-oxygen vibrational
modes in complex silicates was modelled in a small-cluster approximation
by introducing a shell containing first- and second-order neighbours of
the peripheral oxygen atoms of the Si-O cluster. As an example, the
proposed method was applied to study the Raman spectra of different
types of tourmaline, which contain in their structure single
six-membered rings of SiO/sub 4/ tetrahedra. It is shown that in the
range 450-750 cm/sup -1/ the Raman spectrum of the ring is sensitive to
the type of cations in octahedral Y-positions and as a result the peaks
shift and their shape modifies. Using such changes, one can estimate the
occupation of Y positions in tourmalines by various cations.
6/ 120
TI = Piezoelectric materials and their applications
AU = Jones, D.J., Prasad, S.E., Wallace, J.B. (Defence Res. Establ. Atlantic,
Dartmouth, NS, Canada)
SO = Key Eng. Mater. (Switzerland), 71-144, vol.122-124, 1996
PU = Trans Tech Publications
AB = Over 100 years ago, Jacques and Pierre Curie experimentally confirmed
the presence of the piezoelectric effect in quartz, Rochelle salts and
tourmaline single crystals. Within the last 50 years, a number of
ceramic and polymer materials with non-symmetrical crystal structures
have also been found to exhibit the piezoelectric effect. The discovery
of strong piezoelectricity in these materials has has led to their
commercialization and has been a major factor in the development of a
wide range of applications. This paper begins with a review of the
fundamental properties of piezoelectric materials. A description of the
important types of piezoelectric materials and their characteristics are
presented next, followed by discussions of selected applications, with
additional applications listed in tabular format.
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7/ 120
TI = pH self-controlling induced by tourmaline
AU = Nishi, Y., Yazawa, A., Oguri, K., Kanazaki, F., Kaneko, T. (Dept. of
Mater. Sci., Tokai Univ., Kanagawa, Japan)
SO = J. Intell. Mater. Syst. Struct. (USA), 260-3, vol.7, no.3, May 1996
PU = Technomic Publishing
AB = The effect of tourmaline on pH control is investigated. The hydrogen ion
concentration tremendously decreases for 1 h. The concentration
approaches 10/sup -7/ mol/l at infinite time. On the other hand, the
concept of materials intelligence (I/sub k/) has been suggested. If the
f/sub h/ value is 50, we can determine the I/sub h/ value [I/sub h/(50)]
for tourmaline. The I/sub h/(50) and P/sub r/ (practicality) values are
0.38 and 0.70 for tourmaline.
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8/ 120
TI = Piezoelectric and elastic properties of orthorhombic LiH/sub 2/PO/sub 3/
and LiH/sub 2/PO/sub 4/
AU = Haussuehl, S. (Inst. fur Kristallographie, Koln Univ., Germany)
SO = Cryst. Res. Technol. (Germany), 323-7, vol.31, no.3, 1996
PU = Akademie Verlag
AB = Single crystals of LiH/sub 2/PO/sub 3/ and LiH/sub 2/PO/sub 4/, both of
space group symmetry Pna2/sub 1/, with dimensions up to 40 mm were grown
from aqueous solutions by controlled evaporation. Pyroelectric,
dielectric, piezoelectric, elastic and thermoelastic properties were
studied by standard methods. The static piezoelectric constants d/sub
333/ exceed d/sub 111/ of alpha -quartz by only a factor 2. The
pyroelectric effects reach 3 times and 7 times, respectively, that of
tourmaline. The mean elastic stiffness of the phosphite is 13% smaller
than that of the phosphate, a phenomenon also observed in the
corresponding sodium and potassium salts.
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9/ 120
TI = Moessbauer and optical spectrometry of selected schoerl-dravite
tourmalines
AU = Fuchs, Y., Lagache, M., Linares, J., Maury, R., Varret, F. (Lab. de
Miner. Exp. et Appliquee, Univ. Pierre et Marie Curie, Paris, France)
SO = Hyperfine Interact. (Switzerland), 245-58, vol.96, no.3-4, Oct. 1995
AB = Spectrometric studies were carried out on samples of tourmaline
(schoerl-dravite series) from geological environments where
first-phase-formed tourmaline underwent influence of geochemically
different fluids. Samples are from a differentiated magmatic complex of
Trento-Alto Adige, Italy, and from hydrothermal gold and silver deposits
of the Humboldt Range, Nevada, USA. Chemical data were obtained from
electron microprobes. The results of Moessbauer measurements suggest
three to five doublets. Fe occurs in two valence states. The Z-site,
usually fulfilled with Al/sup 3+/ and Fe/sup 3+/, is assigned only to
Al/sup 3+/ and Fe/sup 2+/. This location was found in nearly all samples
studied. In the Y-site Fe/sup 2+/ and Fe/sup 3+/ are obviously present.
Isomer shifts with intermediate values can be assumed to be related to
intervalence charge transfer (IVCT). Optical spectroscopy reveals
absorption bands at 9000 and 14000 cm/sup -1/, which are assigned to a
charge transfer between Fe/sup 2+/ and Fe/sup 3+/, the 23000 cm/sup -1/
absorption band is supposed to be due to Fe/sup 2+/ to Ti/sup 4+/ charge
transfer. The occupation of the Z-site only by Fe/sup 2+/ and the
coexistence of divalent and trivalent Fe in the Y-site could be
explained by selective oxidation in Y-site through a late process.
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10/ 120
TI = Application of new thermopiezoelectric effect to thermo- and
piezoelectret records
AU = Poplavko, Y.M., Otkox, A.I., Krainyk, G.G., Pereverzeva, L.P. (Kiev
Polytech. Inst., Ukraine)
SO = 8th International Symposium on Electrets. ISE 8 Proceedings (Cat.
No.94CH3443-9), 731-5, xxv+1046, 1994
PU = IEEE, New York, NY, USA
AB = It was originally shown that partially clamped piezoelectric crystals
decrease the symmetry of their polarization response to thermal or
elastic excitation. As a result any ordinary piezoelectric material
(such as alpha -quartz) and even materials that are pyroelectric
perpendicularly to their unique polar axis (such as Y-cut tourmaline)
acquire the polar (vectorial) electric response on scalar thermal
influence. In connection with this effect we discovered Y-surface
thermoinduced electric charges on LiTaO/sub 3/ crystals which manifest
themselves through electrooptical patterns. A "thermoelectret" effect is
likely to be applied as reversible thermoinduced records. Our recent
study uncovered a simple stress-induced method to produce well-defined
and reversible records on Y-LiTaO/sub 3/ plates that can be ascribed to
a "piezoelectret" nature.
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11/ 120
TI = Tourmaline and lithium niobate reaction with water
AU = Nakamura, T., Fujishira, K., Kubo, T., Iida, M. (Dept. of Electron.,
Tokai Univ., Hiratsuka, Japan)
SO = Ferroelectrics (Switzerland), 207-12, vol.155, no.1-4, 1994
AB = Both tourmaline group and lithium niobate crystals have been found to
react with water, giving rise to both a pH value variation and an
electrical conductivity variation. The mechanism of this occurence has
been analyzed.
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12/ 120
TI = Gold-quartz veins in metamorphic terranes and their bearing on the role
of fluids in faulting
AU = Robert, F., Boullier, A.-M., Firdaous, K. (Geol. Survey of Canada,
Ottawa, Ont., Canada)
SO = J. Geophys. Res. (USA), 12861-79, vol.100, no.B7, 10 July 1995
AB = Gold-quartz-tourmaline-carbonate-pyrite veins of the Val d'Or district
in the Late Archean southeastern Abitibi greenstone belt, Canada, have
been structurally documented in detail and offer a good opportunity for
studying fault-related processes. The veins are well exposed in three
dimensions within numerous deep mines (up to 2 km) and they typify the
structural character of many other mesothermal gold-quartz vein deposits
and districts around the world. The structural attributes of these
gold-quartz veins, constraints from fluid inclusions, and an
interpretation of the dynamics of their development are presented and
provide a basis for discussion of potential relationships with
earthquake processes.
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13/ 120
TI = Moessbauer effect and TEM in mineralogy
AU = Ferrow, E.A. (Dept. of Miner. & Pet., Lund Univ., Sweden)
SO = Hyperfine Interact. (Switzerland), 121-34, vol.90, no.1-4, Nov. 1994
AB = Moessbauer effect (ME) provides useful information on oxidation state,
co-ordination number, co-ordination state, site occupancies, and
magnetic properties of Fe-bearing phases. The information gained by ME
together with the information provided by other conventional techniques
is used to extract temperature, pressure, and kinetics of rock-forming
processes. Nevertheless, ME requires that the phases studied are
homogeneous over an extremely large volume and that Fe is a major
component of the system. Transmission electron microscopy (TEM), on the
other hand, provides similar information over a very small volume for a
system of any component. However, present TEM spectrometers do not
provide sufficient resolution to detect the mixed oxidation state. A
complete characterisation of phases in rocks requires, therefore, that
conventional techniques be combined with TEM.
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14/ 120
TI = Moessbauer effect study of the crystal chemistry of tourmaline
AU = Ferrow, E.A. (Dept. of Miner. & Pet., Lund Univ., Sweden)
SO = Hyperfine Interact. (Switzerland), 689-95, vol.91, no.1-4, Nov. 1994
AB = One of the main features of the tourmaline group of minerals is that the
six coordinated Y and Z sites, possessing different point group
symmetries and sizes, share edges. The ME parameters are, therefore,
controlled by the mechanisms by which the tourmaline structure obtains
congruency along the common edge between the two octahedra. For example,
if the size of the Y site in elbaite is increased by replacing Li and Al
by Fe/sup 2+/, then, for small values of Fe/sup 2+/, size congruency is
maintained by simultaneously replacing Al by Fe/sup 2+/ at the Z site.
The ME spectra of Fe-bearing elbaite are therefore characterised by two
doublets assigned to Fe/sup 2+/ in the Y and Z sites. For higher values
of Fe/sup 2+/ at the Y site, however, the tourmaline structure reduces
the misfit further by oxidation of Fe/sup 2+/ at the Y site. The effect
of the second mechanism is to increase Fe/sup 2+/-Fe/sup 3+/ interaction
centres and thereby promote charge delocalisation. These Fe-Fe charge
interactions introduce three more peaks with ME parameters intermediate
between Fe/sup 2+/ and Fe/sup 3+/. On the other hand, the replacement of
Fe/sup 2+/ by Mg/sup 2+/ reduces the density of Fe/sup 2+/-Fe/sup 3+/
centres, blocks Fe-Fe charge interactions and increases the intensity of
Fe/sup 3+/.
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15/ 120
TI = Cu-bearing tourmaline from Paraiba, Brazil
AU = MacDonald, D.J., Hawthorne, F.C. (Dept. of Geol. Sci., Manitoba Univ.,
Winnipeg, Man., Canada)
SO = Acta Crystallogr. C, Cryst. Struct. Commun. (Denmark), 555-7, vol.C51,
no.4, 15 April 1995
AB = Crystal structure refinement of copper-bearing tourmaline from Paraiba,
Brazil, rim composition (Na/sub 0.54/Ca/sub 0.05/)(Li/sub 1.21/Mn/sub
0.04/Cu/sub 0.10/Al/sub 1.66/)Al/sub 6/(Si/sub 5.92/-Al/sub 0.08/)O/sub
18/(BO/sub 3/)/sub 3/ ((OH)/sub 3.56/F/sub 0.44/), core composition
(Na/sub 0.55/Ca/sub 0.01/)(Li/sub 1.16/Mn/sub 0.08/Cu/sub 0.05/Al/sub
1.71/)Al/sub 6/(Si/sub 5.88/-Al/sub 0.12/)O/sub 18/(BO/sub 3/)/sub 3/
((OH)/sub 3.70/F/sub 0.30/), shows the octahedrally coordinated Z site
to be completely occupied by Al, and Li to occur only at the
octahedrally coordinated Y site. The high displacement factors at the O1
and O2 positions indicate significant positional disorder that is
induced by occupancy of the X ( equivalent to 0.57Na+0.43 Square
Operator (vacancy)) and Y ( equivalent to 1.2Li+1.8(Al+Mn/sup 3+/))
sites by cations of very different size and charge.
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16/ 120
TI = Collection and analysis of powder diffraction data with near-constant
counting statistics
AU = Madsen, I.C., Hill, R.J. (Div. of Mineral Products, CSIRO, Port
Melbourne, Vic., Australia)
SO = J. Appl. Crystallogr. (Denmark), 385-92, vol.27, pt.3, 1 June 1994
AB = The concept of a variable-counting-time (VCT) strategy for use in
Rietveld analysis of X-ray powder diffraction data was introduced by
Madsen and Hill (Adv. X-ray Anal. (1992), 35, 39-47). This strategy is
based on a function that increases the counting time used at each step
in the scan in a manner that is inversely proportional to the decline in
reflection intensity that inevitably results from the combined effects
of Lp factor, scattering factor and thermal vibration. The present work
extends the VCT function to include the effects of reflection
multiplicity, cylindrical-sample (capillary) absorption and
monochromator polarization. The new algorithm has been incorporated into
a PC computer program and applied to the collection of data from samples
of LaB/sub 6/, tourmaline, forsterite and boehmite. Subsequent analysis
of the data using the Rietveld method has shown that VCT data can
produce more accurate atomic coordinates and site occupancies, lower
residual 'noise' in difference Fourier maps and more stable refinement
of 'light' atoms.
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17/ 120
TI = Tourmaline group crystals reaction with water
AU = Nakamura, T., Kubo, T. (Dept. of Electron., Tokai Univ., Kanagawa,
Japan)
SO = Ferroelectrics (UK), 13-31, vol.137, no.1-4, 1992
AB = The pyroelectricity in tourmaline crystals has proved to be the
secondary pyroelectric effect due to the thermal expansion and the
piezoelectricity. On the c-face of a tourmaline powder of radius a ( mu
m), there exists the electric field of 10/sup 7/ (V/m) which decreases
following (a/r)/sup 3/ at distance r and is faint at teen ( mu m) value
of r. Several attributes of water that has contacted tourmalines undergo
definite changes. Quite a few novel applications of tourmalines are
possible.
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18/ 120
TI = An empirical oxygen- and hydrogen-isotope geothermometer for
quartz-tourmaline and tourmaline-water
AU = Kotzer, T.G., Kyser, T.K., King, R.W., Kerrich, R. (Res AECL, Chalk
River Labs., Ont., Canada)
SO = Geochim. Cosmochim. Acta (UK), 3421-6, vol.57, no.14, July 1993
AB = Oxygen-isotope equilibration temperatures of coexisting quartz,
muscovite, illite, chlorite, and biotite from a variety of geologic
environments have been used in conjunction with the delta /sup 18/O and
delta D values of associated tourmaline to formulate empirical
quartz-tourmaline and tourmaline-water isotope fractionation factors
over temperatures from 200 to 600 degrees C. The fractionation factors
determined using this method are given.
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19/ 120
TI = Calibration of dynamic pressure transducer by hydraulic impulse
generator system
AU = Kim, K.J., Han, S.W., Lee, H.J., Woo, S.Y., Kim, B.S. (Mass Lab., Korea
Res. Inst. of Stand. & Sci., Daejon, South Korea)
SO = Korean Appl. Phys. (South Korea), 521-5, vol.5, no.6, Nov. 1992
AB = Dynamic pressure transducer calibration system which has hydraulic
impulse generator was established and the sensitivity of PCB118A02
pressure transducer was measured with tourmaline sensor as the
reference. The magnitudes of pressure impulse was varied from 32.68
MPa(4739.8 psi) up to 135.02 MPa (19582 psi) with the interval of 20.685
MPa (3000 psi). The average sensitivity of PCB118A02 was found to be
15.102 pC/MPa (0.104 pC/psi), which showed 5.3% difference from the
value provided by manufacturer.
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20/ 120
TI = 11th European Symposium on Fluid Inclusion Research (ECROFI XI)
SO = Eur. J. Mineral. (West Germany), vol.4, no.5, Sept.-Oct. 1992
AB = The following topics were dealt with: removal of O/sub 2/ from N/sub 2/
purge gas; modelling of clathrate stability in fluid inclusions; water,
hydrates, and pH in fluid inclusions; fluid inclusion gases from
geothermal systems; CO/sub 2/-bearing fluids in the Aluto-Langano
geothermal field, (Ethiopia); fluid mixing during ore deposition; fluid
mixing and mesothermal Au mineralisation; fluid evolution in a
greisen-tourmaline system; fluid inclusions and Au-W mineralisation;
hydrothermal calcites and Tennessee Zn deposits; structure of geothermal
and epithermal systems; fluid inclusion re-equilibration and evolution
in Ghana; rock chemistry and fluid inclusions in the Serre batholith,
Italy; fluid evolution and ore deposition in the Harz Mountains; fluid
evolution in a Proterozoic Zn-Cu-Pb sulphide deposit; the Perda Majori
(Sardinia) W-Mo deposit; fluid inclusions in pegmatites (Elba); fluid
inclusions in eclogitic metagabbros; silicate-melt inclusions in
Vesuvius lavas; cordierite andalusite-bearing mica schist from W.
Hungary; mantle fluids in pyroxenite nodules; C-O-H-N-NaCl fluids in a
granitic complex; fluid inclusions in the Gallura intrusive complex
(Sardinia); and inclusions in thermally metamorphosed salt beds.
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21/ 120
TI = Timing of Cenozoic extensional tectonics in west Turkey
AU = Seyitoglu, G., Scott, B.C., Rundle, C.C. (Dept. of Geol., Leicester
Univ., UK)
SO = J. Geol. Soc. (UK), 533-8, vol.149, pt.4, July 1992
AB = The timing of the transition from compressional to extensional tectonics
in the late Cenozoic evolution of west Turkey has been constrained by
K-Ar geochronology from acidic volcanic rocks and tourmaline
leucogranite dykes in the Gordes basin. Dacites and rhyolites in the
centre of the Gordes Neogene sedimentary basin cut both the basement
ophiolites of the Izmir-Ankara suture zone and the Neogene sediments. On
the basin's eastern margin the leucogranites cut metamorphic basement
along a major NE-SW-trending normal fault. Pebbles of these
leucogranites occur in adjacent Neogene tuffites and conglomerates. K-Ar
dates on biotites from the central volcanic rocks vary from 18.4+or-0.8
Ma to 16.3+or-0.5 Ma (early Miocene) whilst muscovite from a
leucogranite on the eastern margin of the basin provides ages of
24.2+or-0.8 Ma and 21.1+or-1.1 Ma (latest Oligocene to early Miocene).
Geochronological data and field relationships demonstrate that the
earlier compressional regime had been replaced by extensional tectonics
by latest Oligocene-early Miocene.
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22/ 120
TI = Frontiers in Isotope Geosciences
SO = Chem. Geol. (Isot. Geosci. Sect.) (Netherlands), vol.101, no.1-2, 10
June 1992
AB = The following topics were dealt with: stable isotope analysis, in situ
laser microprobe techniques, O, feldspar, quartz, LASSIE-laser ablation
sampler for stable isotope extraction, carbonates, minerals, sulphides,
S, Axial Seamount, C, gas chromatography-isotope ratio mass
spectrometry, Dosimetry System 1986, noble gases in ancient fluids, B,
negative thermal ionisation mass spectrometry, geochemistry, tourmaline,
single zircon dating, Pb, Corsica, Hercynian granites, Scotland,
Southern Uplands, detrital muscovites, laser /sup 40/Ar-/sup 39/Ar ages,
Th, pyrites, magnetites, diamond, extreme energy filtering, H, Sr,
Cameca ims-3f ion microprobe, Cameca ims-300, Isolab 54.
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23/ 120
TI = Electric properties of tourmalines at high temperature and pressure
AU = Lastovichkova, M., Lebedev, T.S., Shepel', S.I. (Geophys. Inst., Acad of
Sci., Prague, Czechoslovakia)
SO = Geofiz. Zh. (Ukrainian SSR), 1990
AB = Irreversible physico-chemical changes taking place in different media
are responsible for the different dependences of the electrical
conductivity of tourmalines in argon and in air. Temperature and
moisture saturation have a more appreciable effect than does pressure on
the electrical conductivity of tourmalines. Pressure and chemical
composition (an increase in the content of the oxides of iron) have no
noticeable effect on the absolute magnitude of electrical conductivity
up to the critical temperature, but do considerably reduce activation
energy and the logarithm of the pre-exponential coefficient of these
minerals. A very marked increase in electrical conductivity and minimal
T/sub c/ values are seen in the most ferruginous tourmalines. Electrical
conductivity is low at temperatures of less than 400-500 degrees C, and
therefore the effect of electromagnetic field frequency is quite
apparent within that temperature range.
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24/ 120
TI = Thermal oxidation study of natural tourmaline using Mossbauer effect
AU = Varma, H.V. (Dept. of Phys., Dr. H.S.G. Univ., Sagar, India)
SO = Indian J. Phys. A (India), 293-9, vol.65A, no.4, July 1991
AB = Minerals having hydroxyl group show conversion of ferrous ions to ferric
ions when heated in air. Several mechanisms have been suggested for this
process of conversion of ferrous to ferric. One mechanism which has been
suggested is the hopping mechanism of electron-proton pair. In the case
of tourmaline, using the thermal oxidation and the technique of
Mossbauer effect it has been confirmed that the hopping mechanism is
responsible for the oxidation. The oxidation of ferrous ion takes place
by the ejection of the natural atom of hydrogen rather than a
proton-electron pair. This natural atom of hydrogen hops to the surface
of the sample and oxidizes with atmospheric oxygen to form water.
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25/ 120
TI = Very-high-pressure metamorphism and uplift of coesite-bearing
metasediments from the Zermatt-Saas zone, Western Alps
AU = Reinecke, T. (Inst. fur Miner., Ruhr-Univ. Bochum, West Germany)
SO = Eur. J. Mineral. (Germany), 7-17, vol.3, no.1, Jan.-Feb. 1991
AB = The metapelitic assemblage of a very-high-pressure metamorphic
manganiferous quartzite occurring at Lago di Cignana, Valtournanche,
Western Alps, Italy, on top of eclogite-facies metaophiolites, provides
an outstanding record of the P-T evolution during subduction and
subsequent uplift in a segment of the oceanic Zermatt-Saas zone. At peak
metamorphic conditions of 590-630 degrees C, 26-28 kbar, rim
compositions of pyrope-rich spessartine containing up to 41 mol.% pyrope
coexisted with coesite, talc, kyanite, phengite, paragonite, braunite,
piemontite, haematite, rutile, dravitic tourmaline, Mg-rich ardennite,
apatite and zircon under high H/sub 2/O-activity. Coesite is exclusively
present as rare inclusions in tourmaline and pyrope-rich garnet and has
partially or completely inverted to polycrystalline quartz. The
established P-T path provides evidence that pelagic sediments forming
part of the lithosphere of the former Piemonte-Ligurian ocean were
subducted to depths of about 90 km. Preservation of the
very-high-pressure metamorphic assemblage formed on an apparent geotherm
of about 7 degrees C/km may have been favoured by the limited access of
hydrous fluids and by a retrograde P-T path on which decompression was
associated with major cooling.
+
26/ 120
TI = Stratigraphic development and hydrothermal activity in the central
Western Cascade Range, Oregon
AU = Cummings, M.L., Michael Pollock, J., Thompson, G.D., Bull, M.K. (Dept.
of Geol., Portland State Univ., OR, USA)
SO = J. Geophys. Res. (USA), 19601-10, vol.95, no.B12, 10 Nov. 1990
AB = Two volcanic sequences bounded by erosional unconformities compose the
stratigraphy of the North Santiam mining district, Western Cascade
Range, Oregon. Diorite, granodiorite, and leucocratic quartz porphyry
dikes, stocks, and sills intrude the breccias, flows, and tuffs of a
volcanic center in the older Sardine Formation. Tourmaline-bearing
breccia pipes are associated with the porphyritic granodiorite
intrusions. An erosional unconformity separates the Sardine Formation
from the overlying Elk Lake formation. The alteration patterns in the
two formations are consistent with the development of hydrothermal
systems during the eruption of each formation. However, the development
of the two hydrothermal systems is separated by a period of erosion of
the older volcanic pile.
+
27/ 120
TI = The symmetry of the natural optical activity and similar effects
AU = Malinowski, S. (Inst. of Phys., Lodz Univ., Poland)
SO = Acta Phys. Pol. A (Poland), 543-53, vol.A77, no.4, April 1990
AB = For some symmetry of media, only the transverse waves can propagate if
there is no spatial dispersion. On the other hand if there is a spatial
dispersion, then for the same symmetry one can distinguish three types
of directions: (i) the ones along which only the transverse waves
propagate, (ii) the ones along which the transverse waves propagate
together with the waves which are neither transverse nor longitudinal
(such waves will be called skew ones), (iii) the ones along which only
the skew waves propagate. In case (ii) the skew wave is, as a rule, more
absorbed than the pure transverse wave; the pure transverse wave is,
first of all, the extraordinary wave polarized along the optical axis
(e.g. in tourmaline).
+
28/ 120
TI = A scattered ring in a natural crystal of tourmaline
AU = Ja, Y.H. (Telecom Australia Res. Lab., Clayton, Vic., Australia)
SO = J. Opt. (France), 41-3, vol.21, no.1, Jan.-Feb. 1990
AB = A scattered circular ring was observed in a natural crystal of
tourmaline, when illuminated with a He-Ne laser beam. It is suggested
that the scattered ring be due to the scattering of the incident beam by
a very slender cylinder-like microstructure inside the crystal, and the
microstructure might be formed by impurity ions, such as Fe/sup 3+/.
+
29/ 120
TI = Provenance studies of Chirala coastal glass sand deposit, east coast of
India
AU = Sankara Pitchaiah, P., Rao, A.T. (Dept. of Geol., Nagarjuna Univ.,
Nagarjunanagar, India)
SO = Indian J. Mar. Sci. (India), 195-7, vol.18, no.3, Sept. 1989
AB = The mineralogy and chemical and optical properties of the Chirala
coastal glass sand deposit have been studied. Common hornblende and
epidotes are predominant among the nonopaque minerals. Euhedral zircons
are common. The hornblende and epidote abundance and their chemical and
optical properties suggest the Nellore schist belt as the chief source
for these sands. The shape and length-breadth ratios of zircons further
support a schist belt provenance. The low abundance of garnets,
sillimanites, rounded zircons, and zircon high-elongation frequencies
indicates a minor contribution from khondalites and charnockites. The
major confinement of the Gundlakamma river to Dharwarian schistose rocks
and Archaean granitic gneisses suggest that the Nellore schist belt
might have been actively eroded and have contributed the sediment to a
large extent to this coastal sand belt.
+
30/ 120
TI = Dielectric properties of tourmaline under different conditions
AU = Mishra, S., Krishna Rao, A.V., Rao, K.V. (Dept. of Phys., Indian Inst.
of Technol., Kharagpur, India)
SO = Phys. Status Solidi A (East Germany), K115-18, vol.114, no.1, 16 July
1989
AB = The authors report measurements on the dielectric properties of
tourmaline single crystals subjected to different treatments like
quenching, X-ray or gamma -ray irradiation and the application of DC
biasing voltage. The frequency dependence of the dielectric constant and
dielectric loss tangent at room temperature is studied.
+
31/ 120
TI = Geology of the Ulugh Muztagh area, northern Tibet
AU = Burchfiel, B.C., Molnar, P., Zhao Ziyun, Liang K'uangyi, Wang Shuji,
Huang Minmin, Sutter, J. (Dept. of Earth, Atmos. & Planetary Sci., MIT,
Cambridge, MA, USA)
SO = Earth Planet. Sci. Lett. (Netherlands), 57-70, vol.94, no.1-2, Aug. 1989
AB = Within the Ulugh Muztagh area, north central Tibet, an
east-west-trending ophiolitic melange marks a suture that apparently was
formed during a late Triassic or slightly younger collision between a
continental fragment to the south and the rest of Asia. The southern
continental fragment carries a thick sequence of upper Triassic
sandstone, but the contact between the sandstone and the ophiolitic
melange is covered by a younger redbed sequence of unknown age. A suite
of 2-mica, tourmaline-bearing leucogranite plutons and dikes intruded
the Triassic sandstone at shallow crustal levels 10.5 to 8.4 Ma. These
rocks are interpreted to have been derived by the partial melting of
crustal material. The authors interpret this to mean that crustal
thickening began in this part of the Tibetan plateau at least by 10.5
Ma. Welded rhyolitic tuff rests on a conglomerate that consists of
abundant debris from the Ulugh Muztagh intrusive rocks and has yielded
Ar/Ar ages of about 4 Ma. Crustal thickening may have continued to 4 Ma.
+
32/ 120
TI = Effect of alpha -recoil damage on the elastic moduli of zircon and
tourmaline
AU = Ozkan, H. (Dept. of Phys., Middle East Tech. Univ., Ankara, Turkey)
SO = Nuclear Physics Applications on Materials Science. Proceedings of the
NATO Advanced Science Institute, 447-8, ix+458, 1988
PU = Kluwer Acad. Publishers, Dordrecht, Netherlands
AB = The author reports on the effect of alpha -recoil damage on the elastic
moduli of zircon and tourmaline. Elastic wave velocities of seven
different zircon samples have been measured by ultrasonic pulse-echo
methods. They have observed 31% and 28% decrease in the longitudinal and
shear wave velocities, respectively. All the elastic constants except
C/sub 66/ decrease systematically and markedly (up to 69%) with
radiation damage and approach two common saturation values of 150 GPA
and 49 GPA. Oriented single crystals and powders of tourmaline have been
irradiated with thermal neutrons up to total dose of 7, 6*10/sup 18/
n/cm/sup 2/. Elastic wave velocity and X-ray diffraction measurements
prior and after several thermal neutron irradiations have indicated that
tourmaline crystals are rather stable up to total dose of 8*10/sup 17/
n/cm/sup 2/.
+
33/ 120
TI = Thermal expansion of tourmaline single crystals from 80 to 300 K
AU = Tatli, A., Pavlovic, A.S. (Dept. of Sci. Educ., Middle East Tech. Univ.,
Ankara, Turkey)
SO = Phys. Rev. B, Condens. Matter (USA), 10072-4, vol.38, no.14, 15 Nov.
1988
AB = The thermal expansion and coefficient of linear thermal expansion of
elbaite, schorl, and uvite specimens in the a and c directions have been
determined from 80 K to room temperature with use of the standard
strain-gauge technique. At room temperature it was found that for
elbaite, alpha /sub a/=3.86*10/sup -6/ K/sup -1/ and alpha /sub
c/=9.11*10/sup -6/ K/sup -1/; for schorl, alpha /sub a/=3.48*10/sup -6/
K/sup -1/ and alpha /sub c/=8.54*10/sup -6/ K/sup -1/; and for uvite,
alpha /sub a/=3.17*10/sup -6/ K/sup -1/ and alpha /sub c/=8.32*10/sup
-6/ K/sup -1/. It was observed that the anisotropy in thermal expansion
along the a and c directions of tourmalines is directly related to the
anisotropy in the corresponding adiabatic elastic constants.
+
34/ 120
TI = Role of natural radiation in tourmaline coloration
AU = Reinitz, I.M., Rossman, G.R. (Div. of Geol. & Planetary Sci., California
Inst. of Technol., Pasadena, CA, USA)
SO = Am. Mineral. (USA), 822-5, vol.73, no.7-8, July-Aug. 1988
AB = The optical spectra of elbaite tourmalines subjected to large,
controlled doses of gamma radiation have been compared to those of
natural specimens. Both naturally pink and laboratory-irradiated
elbaites show the same spectroscopic features. Optical absorption
features of Mn/sup 2+/ in nearly colorless elbaites are lost during
laboratory irradiation, indicating a Mn/sup 2+/ to Mn/sup 3+/
transformation during the radiation process. Measurements of the
radiation levels in tourmaline pockets in southern California pegmatites
have been used to compute the doses that natural samples should have
experienced over geologic time. These doses generally correspond to the
doses required to restore the color to elbaites that have been
decolorized by laboratory heat treatment, indicating that color in
naturally pink tourmaline is a product of natural radiation. This
radiation could have been effective only after the pegmatite cooled
below the decolorizing temperature of tourmaline, suggesting that most
pink elbaites originally grew nearly colorless in the pegmatites and
only later attained their pink color through oxidation of Mn via
ionizing radiation.
+
35/ 120
TI = Electron paramagnetic resonance of atomic hydrogen centers in rubellite
AU = De Camargo, M.B., Pontuschka, W.M., Isotani, S. (Sao Paulo Univ.,
Brazil)
SO = An. Acad. Bras. Cienc. (Brazil), 293-8, vol.59, no.4, 1987
AB = The authors report a new atomic hydrogen center, U/sub R/, observed in
rubellite (pink tourmaline) gamma -irradiated at room temperature with
EPR measurements. These measurements provided the experimental support
for the model they have developed in order to explain the high stability
of atomic hydrogen in this material.
+
36/ 120
TI = Optical absorption spectroscopy of natural and irradiated pink
tourmaline
AU = Bueno de Camargo, M., Isotani, S. (Inst. de Fisica, Sao Paulo Univ.,
Brazil)
SO = Am. Mineral. (USA), 172-82, vol.73, no.1-2, Jan.-Feb. 1988
AB = The authors have studied the Brazilian natural pink tourmaline through
polarized optical absorption measurements. The effects of increasing
doses of gamma -rays from /sup 60/Co on the spectra were determined
(maximum of 20 MGy). The following optical absorption bands were
observed: 8500 and 14800 cm/sup -1/ assigned to d-d transitions of
Fe/sup 2+/ in b and c sites, respectively; 19500 and 25500 cm/sup -1/
assigned to /sup 5/E to /sup 5/A/sub 1/ and /sup 5/B/sub 2/ to /sup
5/A/sub 1/ d-d transitions of Mn/sup 3+/, respectively.
+
37/ 120
TI = Thermal deformations and phase transformations in tourmalines
AU = Filatov, S.K., Gorskaya, M.G., Bolotnikova, N.I. (A.A. Zhdanov Leningrad
State Univ., USSR)
SO = Izv. Akad. Nauk SSSR Neorg. Mater. (USSR), 594-9, vol.23, no.4, April
1987
AB = Various areas of application of tourmaline, especially as piezoelectric
crystals (space group R3m) for measuring explosion force, make study of
its behavior in a wide temperature range desirable. The authors used
thermoradiography to observe phase transformations directly and to
measure for the first time thermal deformations of tourmalines varying
in composition. The four specimens studied belong to two isomorphic
types of tourmalines most widespread in nature, viz. Fe-Mg (schorl
dravite) and Fe-Li, Al (schorl elbaite).
+
38/ 120
TI = Color and luminescent properties of minerals in various redox conditions
AU = Yarovoi, P.N., Medvedev, V.Ya., Ivanova, L.A., Serykh, S.V.
SO = Zh. Prikl. Spektrosk. (Byelorussian SSR), 938-43, vol.46, no.6, June
1987
AB = The authors examine the photoluminescence and X-ray luminescence and the
coloring of such minerals as charoite, nephrite, kanasite, tourmaline,
and spinel subjected to isothermal holding in hydrothermal conditions at
high pressure, in various redox conditions. The mineral samples are held
at P=40-100 MPa H/sub 2/O+10% H/sub 2/, H/sub 2/O+10% O/sub 2/ and
T=300-500 degrees C. A nitrogen laser is used as the source of
photoexcitation, and the X rays are generated by means of URS-55A unit.
The luminescence spectra are recorded using a DMR-23 monochromator, a
U5-6 amplifier, and in Z-3 automatic recorder, and the lifetime is
analyzed on an S1-75 oscillograph.
+
39/ 120
TI = Zonal distribution of tourmaline types in the hydrothermal convective
system at Novazza (Bergamasc Alps, Northern Italy)
AU = Fuchs, Y. (Univ. Pierre et Marie Curie, Paris, France)
SO = C.R. Acad. Sci. II, Mec. Phys. Chim. Sci. Univers Sci. Terre (France),
1507-10, vol.305, no.19, 14 Dec. 1987
AB = The volcanogenic deposits of Permian age in the Collio Orobico basin can
be divided into two major cycles. In Novazza the calderic system formed
during the first stage shows a resurgent doming at the end of this
cycle. During this period and during the initial stage of the second
volcanic cycle a hydrothermal system developed in the resurgent doming
area. It is characterized by pyrophyllitisation, pervasive
sericitization and tourmalinisation. The composition of the sericites
changes from muscovite to a more celadonitic composition along a
phengitic trend line from the alkali central area toward the outer zone,
with tourmalines changing from alkali deficient, aluminium rich dravites
to aluminium poor, weakly alkali deficient schorl or even ferric iron
tourmalines. The andesitic low depth intrusions belonging to the initial
phase of the second cycle induce some local variations
(ferro-muscovites).
+
40/ 120
TI = The location of boron-containing dust in the lung, utilising
neutron-induced autoradiography techniques with a CR-39 solid state
track detector
AU = Morris, K.J., Batchelor, A.L. (MRC Radiolbiol. Unit, Chilton, UK)
SO = Phys. Med. Biol. (UK), 1501-8, vol.32, no.11, Nov. 1987
AB = The authors report two new developments in the use of CR-39 to measure
boron-containing particles in the lung. In one of these, the relative
amount of particulate boron located within a lung tissue section can be
estimated by counting the number of tracks produced by the /sup 10/B (n,
alpha ) reaction. In the other, a lung section, and the location of
boron-containing particles within it, can be imaged onto a plate of
CR-39. Also discussed, as an incidental finding, is a separate technique
to image a lung tissue section onto a pre-etched CR-39 plate while still
preserving the original section for staining and histological
examination. The ultimate aim is to measure the relative mass and
spatial distribution of tourmaline aggregates in post mortem lungs from
Cornish tin miners, using a CR-39 homopolymer solid state track detector
and neutron-induced autoradiography, with subsequent image analysis on a
Quantimet 720.
+
41/ 120
TI = Chemistry of the rock-forming silicates: ortho, ring, and single-chain
structures
AU = Papike, J.J. (Inst. for the Study of Miner. Deposits, South Dakota Sch.
of Mines & Technol., Rapid City, SD, USA)
SO = Rev. Geophys. (USA), 1483-526, vol.25, no.7, Aug. 1987
AB = The crystal chemistry of 21 ortho, ring, and single-chain silicate
structures is reviewed. Structure drawings are presented to portray the
essential crystal chemical features necessary to correctly interpret
chemical data for each minimal or mineral groups. The group considered
are olivine, humite, zircon, sphene, garnet, vesuvianite,
aluminosilicate, topaz, staurolite, chloritoid, epidote, melilite,
beryl, cordierite, tourmaline, axinite, pyroxene, pyroxenoid, pectolite,
sapphirine, and aenigmatite. Electron microprobe data for each group can
be interpreted with various degrees of rigor, depending on whether H/sub
2/O, Fe/sup 2+//Fe/sup 3+/, and other elements not detect by the
microprobe are present. Serious mineral chemists are encouraged to
determine Fe/sup 2+//Fe/sup 3+/ and H/sub 2/O directly. Estimates of
these values using microprobe data are usually imprecise and can lead to
serious errors in interpretation of the chemical formula and thus any
thermodynamic or petrologic inferences that are based on the correct
formula.
+
42/ 120
TI = Piezoelectric polymer pressure sensors
AU = Leaver, P., Cunningham, M.J., Jones, B.E. (Dept. of Electr. Eng.,
Manchester Univ., UK)
SO = Sens. Actuators (Switzerland), 225-33, vol.12, no.3, Oct. 1987
AB = The use of the piezoelectric material polyvinylidene fluoride (PVDF) in
sensors to measure underwater shock wave pressures is described. Its
advantages and disadvantages as a sensor material are compared to those
of conventional tourmaline sensors. Preliminary results from sensors
using this material are shown to compare well with results from
tourmaline sensors. Some irregularities are, however, found in the PVDF
sensor output, but it is anticipated that these can be eliminated by
improved sensor design.
+
43/ 120
TI = Discovery of a tungsten-molybdenum-copper mineralization in the Yaudet
granitic massif in Brittany (France)
AU = Chauris, L. (Dept. of Sci. de la Terre, Bretagne Univ., Brest, France)
SO = C.R. Acad. Sci. II, Mec. Phys. Chim. Sci. Univers Sci. Terre (France),
387-90, vol.305, no.5, 15 July 1987
AB = The late-magmatic evolution of the Yaudet polyphase pluton, intruded
into the joining of two systems of perpendicular faults, has led to the
formation of intra-granitic veins with tourmaline, wolframite,
scheelite, molybdenite, cholcopyrite. . . and of skarns with diopside,
grossular, pyrrhotite, sphalerite, and scheelite.
+
44/ 120
TI = Effect of thermal neutron irradiation on the elastic constants of
tourmaline
AU = Ozkan, H. (Dept. of Phys., Middle East Tech. Univ., Ankara, Turkey)
SO = Radiat. Eff. (GB), 31-8, vol.102, no.1-4, 1987
AB = The effect of thermal neutron irradiation due to the B/sup 10/(n, alpha
)Li/sup 7/ reaction on the elastic wave velocities and the elastic
moduli of tourmaline crystals has been studied. Oriented tourmaline
samples have been irradiated with thermal neutrons to 7.6*10/sup
18/n/cm/sup 2/ and the elastic wave velocities determined by ultrasonic
measurements. The elastic wave velocities are not affected by thermal
neutron irradiation below 8*10/sup 17/n/cm/sup 2/, effects starting to
appear at approximately 1*10/sup 18/n/cm/sup 2/ with more important
decreases of the elastic wave velocities and of the bulk moduli at
fluences of 2.9*10/sup 18/n/cm/sup 2/ and 4*10/sup 18/n/cm/sup 2/. The
decrease of the bulk moduli of the irradiated tourmalines is compared
with that of metamict zircons. X-ray diffraction of the irradiated
specimens indicates that tourmaline remains crystalline up to a thermal
neutron fluence of 7.6*10/sup 18/n/cm/sup 2/.
+
45/ 120
TI = International Mineralogical Association Symposium 'Mineralogy and
Geochemistry of Granites and Pegmatites'
SO = Geochim. & Cosmochim. Acta (GB), vol.51, no.3, March 1987
AB = The following topics were dealt with: granites and pegmatites mineralogy
and geochemistry phase equilibria, vitrophyre, internal differentiation,
B, P, F, Be, U Lac du Bonnet batholith, igneous history, metamorphic
effects, fluid overprinting, Spor Mountain, Serra de Estrela, Portugal,
United States, Canada South Platte, Harney Peak, chemical evolution,
Calamity Peak, plutons, rhythmic layering, oxide minerals, sulphide
minerals, Erajarvi area, Finland, columbite-tantalite crystals zoning,
mica, tourmaline, Bob Ingersoll No.1 Dike, amphiboles zoning, and
progressive oxidation in Daito-Yokota complex, Japan.
+
46/ 120
TI = Pyroelectric, dielectric, piezoelectric and electrooptic properties of
monoclinic nitrilotriacetic acid N(CH/sub 2/COOH)/sub 3/ and
orthorhombic X/sub 2/Zr(N(CH/sub 2/COO)/sub 3/)/sub 2/.2 H/sub 2/O (X=K,
Rb, Cs)
AU = Richter, U., Haussuhl, S. (Inst. fur Kristallographie, Koln Univ.,
Germany)
SO = Cryst. Res. & Technol. (Germany), 539-45, vol.22, no.4, April 1987
AB = Large single crystals of monoclinic nitrilotriacetic acid, N(CH/sub
2/COOH)/sub 3/, NTA, and of orthorhombic isotypic X/sub 2/Zr(N(CH/sub
2/COO)/sub 3/)/sub 2/.2 H/sub 2/O (X=K, Rb, Cs) have been grown from
aqueous solutions. They possess optical quality and have dimensions up
to 10 mm and larger. The complete dielectric, piezoelectric and
electrooptic tensors have been determined. The maximum longitudinal and
transversal piezoelectric effects exceed those of alpha -quartz by
roughly a factor 11. The pyroelectric effects in NTA and in the X/sub
2/Zr-salts (X=K, Rb, Cs) are by about a factor 3 larger than that in
tourmaline, whereas the maximum electrooptic effects amount only to
about half of that in KH/sub 2/PO/sub 4/. Qualitative measurements of
the nonlinear optical properties by the aid of a SHG powder test and on
single crystals revealed effects comparable with those observed in
LiIO/sub 3/. Phase matching is possible in these compounds. Replacing X
by NH/sub 4/ or Tl also acentric crystals are obtained with strong polar
properties.
+
47/ 120
TI = Variation of the elastic constants of tourmaline with chemical
composition
AU = Tatli, A., Ozkan, H. (Dept. of Phys., Middle East Tech. Univ., Ankara,
Turkey)
SO = Phys. & Chem. Miner. (Germany), 172-6, vol.14, no.2, 1987
AB = Elastic wave velocities and lattice parameters of five tourmaline
specimens with different chemical compositions have been measured. The
piezoelectric effects on the elastic constants have been found to be
small and can be neglected. Variations of the elastic wave velocities
and elastic constants of the different tourmaline specimens indicate
that: (i) partial substitution of Al by Fe in the structure decreases
the shear wave velocities, (ii) replacement of Na by Ca increases the
resistance of the structure against shear deformation involving C/sub
66/, (iii) replacement of Al by Mg seems to decrease the resistance of
the structure against longitudinal deformation involving C/sub 33/.
Elastic constants C/sub 11/, C/sub 33/, C/sub 44/ and C/sub 66/ of the
different tourmaline specimens used in this study differ individually by
1.7 percent to 6.7 percent, indicating that the large differences (up to
21%) between the values reported by previous authors cannot be explained
in terms of the chemical composition alone.
+
48/ 120
TI = Fe/sup 2+/-Fe/sup 3+/ interactions in tourmaline
AU = Mattson, S.M., Rossman, G.R. (Div. of Geol. & Planetary Sci., California
Inst. of Technol., Pasadena, CA, USA)
SO = Phys. & Chem. Miner. (Germany), 163-71, vol.14, no.2, 1987
AB = The color and spectroscopic properties of iron-bearing tourmalines
(elbaite, dravite, uvite, schorl) do not vary smoothly with iron
concentration. Such behavior has often been ascribed to intervalence
charge transfer between Fe/sup 2+/ and Fe/sup 3+/ which produces a new,
intense absorption band in the visible portion of the spectrum. In the
case of tourmaline, an entirely different manifestation of the
interaction between Fe/sup 2+/ and Fe/sup 3+/ occurs in which the Fe/sup
2+/ bands are intensified without an intense, new absorption band. At
low iron concentrations, the intensity of light absorption from Fe/sup
2+/ is about the same for E//c and E perpendicular to c polarizations,
but at high iron concentrations, the intensity of the E perpendicular to
c polarization increases more than ten times as much as E//c. This
difference is related to intensification of Fe/sup 2+/ absorption by
adjacent Fe/sup 3+/. Extrapolations indicate that pairs of Fe/sup
2+/-Fe/sup 3+/ have Fe/sup 2+/ absorption intensity approximately 200
times as great as isolated Fe/sup 2+/. Enhanced Fe/sup 2+/ absorption
bands are recognized in tourmaline by their intensity increase at 78 K
of up to 50%. Enhancement of Fe/sup 2+/ absorption intensity provides a
severe limitation on the accuracy of determinations of Fe/sup 2+/
concentration and site occupancy by optical spectroscopic methods.
Details of the assignment of tourmaline spectra in the optical region
are reconsidered.
+
49/ 120
TI = Electrical conductivity of some minerals at high temperature and for
extended times
AU = Lastovickova, M. (Geophys. Inst., Czechoslovakia Acad. Sci., Praha,
Czechoslovakia)
SO = Phys. Earth & Planet. Inter. (Netherlands), 204-8, vol.45, no.2, March
1987
AB = The influence of the time factor on the results of laboratory
measurements of high-temperature electrical conductivity has been
studied. The electrical conductivity of tourmaline, muscovite,
plagioclase, orthoclase, almandine and titanomagnetite was measured in a
dry regime. Examples of decrease, increase, or no change of conductivity
are given for temperatures kept constant for a long time. Interpretation
of some changes of electrical conductivity is discussed.
+
50/ 120
TI = Effects of temperature and irradiation on piezoelectric acoustic
transducers and materials
AU = Broomfield, G.H.
SO = 37, Dec. 1985
AB = This report comprises a compilation of lecture notes on the testing,
selection and application of materials for piezoelectric acoustic
transducers. The construction of high frequency transducers and the
effects of irradiation and temperature on types designed for arduous
service are described. The criteria for assessing piezoelectric
materials are given as a preamble to a brief discussion of the effects
on them of temperature and irradiation. These materials include the
powder-route ceramics, lead metaniobate and lead-zirconate-titanate and
the single crystal materials, quartz, tourmaline, lithium niobate and
strontium niobate. Conclusions on the materials are concerned with the
probable future temperature ranges for their applications.
+
51/ 120
TI = Accessory minerals in the Oban Massif granitoid plutons of southeastern
Nigeria-their qualitative and quantitative significance in fertility
studies
AU = Odigi, M.I. (Dept. of Geol., Port Harcourt Univ., Nigeria)
SO = J. Afr. Earth Sci. (GB), 163-6, vol.5, no.2, 1986
AB = Mineralogical studies show that some of the granitoid intrusives of the
Oban Massif are characterized by concentrations of halogen bearing
accessory minerals, topaz, tourmaline, fluorite and apatite, in addition
to accessory minerals that are contained in 'normal' granites.
Pegmatitic veins, biotite granites and altered basement mica schist and
granodiorite are associated with tin-mineralization and halogen bearing
accessory minerals that influenced mineralization. Hydrothermal fluids
associated with the vein formation have reacted with the rocks along
contact zones to produce wall rock alteration involving physical,
chemical and mineralogical changes. The dispersion of Sn, topaz,
tourmaline, fluorite and apatite in conjunction with alteration could
aid in determining ore-bearing potential as well as delineating areas
suitable for exploration.
+
52/ 120
TI = Tourmaline is more sensitive than quartz-resonance-free pressure
transducers
AU = Vieten, M.
SO = Elektron. J. (Germany), 28, 30-1, vol.20, no.9, 9 May 1985
AB = The resonance frequency of the pick-up element is of crucial importance
for the faithful recording of fast rise times, a sufficiently fast rise
will cause 'ringing'. Piezoelectric transducers can be improved by
employing acceleration compensation and reductions in ringing amplitudes
of up to 70% are attainable. In a further development PCB (Buffalo, USA)
have introduced a 'frequency-optimized' pressure transducer which reduce
ringing to as little as 5%. However, even greater improvements are
possible by employing tourmaline as the pressure-sensitive element.
Unlike quartz, tourmaline is equally pressure-sensitive in every
direction and is also completely insensitive to accelerations. This
means that a much simpler design for pressure transducers is possible.
The author concludes with examples of available transducers, their
characteristics and applications.
+
53/ 120
TI = Luminescence and field emission associated with heating and cooling of
pyroelectric materials: pyroelectroluminescence
AU = Nambi, K.S.V., Rao, S.M.D., Chougaonkar, M.P. (Div. of Health Phys.,
Bhabha Atomic Res. Centre, Bombay, India)
SO = Nucl. Tracks & Radiat. Meas. (GB), 243-7, vol.10, no.1-2, 1985
AB = A systematic study has been undertaken on the luminescence and the field
emission associated with pyroelectric materials during their heating and
cooling. These may be termed as pyroelectroluminescence (PEL) and
thermally stimulated field emission (TSFE), respectively. Results are
presented on various aspects of the PEL as observed on tourmaline,
lithium niobate and triglycene sulphate as well as on the dosimetry of
TSFE electrons using CaF/sub 2/ thermoluminescent (TL) dosimeters. The
cooling-induced pyroelectroluminescence (CIPEL) has invariably been
found to be more reproducible than the luminescence emitted during the
heating cycle. The recording of the CIPEL glow curves in a conventional
TL apparatus presents itself to be a case study of 'inverse TL'.
+
54/ 120
TI = The transitions of Fe/sup 2+/-Fe/sup 3+/ pairs in tourmaline
AU = Shen Guo-Yin, Wan Ke-Nin, Shang-Bo (Inst. of Solid State Phys., Sichuan
Teachers Coll., Chengdu, China)
SO = Acta Phys. Sin. (China), 164-70, vol.34, no.2, Feb. 1985
AB = Crystal field theory has been used to calculate the spin allowed
transition of Fe/sup 2+/ ions with 3d/sup 6/ configuration in the two
substitutional sites of interest in tourmaline, i.e., in b and c-sites
which have C/sub s/ and C/sub 1/ point group respectively, by using
Zhao's SCF d-orbit of Fe/sup 2+/ ion. The transition of Fe/sup
2+/-Fe/sup 3+/ ion pairs, (Fe/sup 2+/(g)-Fe/sup 3+/) to (Fe/sup
2+/(e)-Fe/sup 3+/) which has not previously been studied, is discussed
theoretically. An estimate of the magnitude of the intensity of the
three strongly polarized (E perpendicular to c>>E//c) bands near 9000
cm/sup -1/, 13800 cm/sup -1/, 15000 cm/sup -1/ in the near-infrared
region is given. The interpretation of the near-infrared absorption
spectra of tourmaline is satisfactory.
+
55/ 120
TI = Dielectric properties of tourmaline
AU = Enakshi, D., Rao, K.V. (Dept. of Phys., Indian Inst. of Technol.,
Kharagpur, India)
SO = Phys. Status Solidi a (Germany), K185-9, vol.87, no.2, 16 Feb. 1985
AB = Tourmaline is found to exist as a natural mineral with the chemical
composition XY/sub 3/Al/sub 6/(BO/sub 3/)Si/sub 6/O/sub 18/(OH)/sub 4/
where X represents Na and Y represents Fe/sup 3+/ in schorlite which is
one form of tourmaline. It has a complicated chemical structure; it
crystallises in the ditrigonal, pyramidal class of the hexagonal system
in prismatic crystals with the trigonal prism dominant. The authors
report data on the dielectric constant and loss of schorlite which
occurs commonly in nature in the frequency range 10/sup 2/ to 10/sup 7/
Hz and in the temperature region 30 to 350 degrees C.
+
56/ 120
TI = Electrical response of tourmaline rocks to a pressure impulse
AU = Baird, G.A., Kennan, P.S. (Univ. Coll., Dublin, Ireland)
SO = Tectonophysics (Netherlands), 147-54, vol.111, no.1-2, 1985
AB = An extensive volume of Russian research supports the claim that rock
samples, as distinct from pure crystals, produce a piezoelectric effect
when strained. This work has been largely ignored in the West with the
exception of research concerned with earthquake prediction or associated
phenomena, e.g. earthquake induced light. Quartz is the most common
piezoelectric mineral found in rocks and the small amount of work
carried out in the West has involved this mineral. In this note, some
preliminary studies carried out on rocks rich in tourmaline are
reported. Preferred poled alignments of tourmaline are indicated.
+
57/ 120
TI = Glasslike thermal conductivity of tourmaline at low temperatures
AU = Lawless, W.N., Pandey, R.K. (CeramPhys. Inc., Westerville, OH, USA)
SO = Solid State Commun. (USA), 833-5, vol.52, no.10, Dec. 1984
AB = Thermal conductivity measurements parallel and perpendicular to the
c-axis in tourmaline single crystals are reported in the range of
1.7-35K. The spontaneous polarization is constrained to the c-axis in
tourmaline. The thermal conductivity (K) follows the glasslike K varies
as T/sup 1.9/ below 6K in both crystallographic directions, and the
magnitude of K is in the upper range found in glasses. It is concluded
that the glasslike thermal properties associated with the spontaneous
polarization in ferroelectric-type solids occur isotropically throughout
the crystal and are not limited to the polarization direction.
+
58/ 120
TI = Mineralogy and sources of bottom sediments of Lake Burollos, Egypt
AU = Sabrouti, E. (Faculty of Sci., Alexandria Univ., Alexandria, Egypt)
SO = J. Afr. Earth Sci. (GB), 151-3, vol.2, no.2, 1984
AB = Heavy, carbonate and clay mineralogical studies have been carried out on
sediments of Lake Burollos. Amphibole, pyroxene and epidote are the
common heavy minerals. Less frequent minerals are garnet, alterite,
zircon, biotite, tourmaline, rutile and kyanite. There is remarkable
similarity in heavy mineral assemblage of the lake with that of the
River Nile. Aragonite is the abundant carbonate mineral for the lake
sediments with subordinate high Mg-calcite and calcite. The clay mineral
composition was also studied. The lake sediments are largely contributed
by the River Nile. The heavy minerals and clay minerals show no distinct
regional distribution patterns within the lake and the sediments, to a
great extent, are mineralogically uniform.
+
59/ 120
TI = Pyroelectroluminescence induced by tourmaline
AU = Nambi, K.S.V. (Health Phys. Div., Bhabha Atomic Res. Centre, Bombay,
India)
SO = Phys. Status Solidi a (Germany), K71-3, vol.82, no.1, 16 March 1984
AB = The author presents the pyroelectroluminescence (PEL) glow curves from
an indian pink tourmaline (a) and a Brazilian green tourmaline (b)
recorded during heating up to 360 degrees C and during cooling to room
temperature (25 degrees C). Unlike the more familiar thermally
stimulated luminescence (TSL) glow curves, the PEL glow curves are
characterised by closely spaced 'light bursts' and this becomes easily
evident during the cooling-induced luminescence (CIL) especially when
the cooling proceeds asymptotically to attain the temperature.
+
60/ 120
TI = X-ray fluorescence analysis of Fe, Mn, Cr and V in natural silicate
crystals
AU = Dias, O.L., Pereira Leite Albuquerque, A.R., Isotani, S. (Inst. de
Fisica, Univ. de Sao Paulo, Sao Paulo, Brazil)
SO = An. Acad. Bras. Cienc. (Brazil), 173-8, vol.55, no.2, June 1983
AB = Concentrations of Fe, Mn, Cr and V were determined in samples of beryl,
topaz, tourmaline and spodumene by measuring the first order K/sub alpha
/ fluorescence lines. The intensity of these lines were calibrated by
using beryl as the standard matrix. The matrices were prepared in the
form of pressed pellets with 4:1 mixture of beryl and boric acid, where
transition metal oxides were added.
+
61/ 120
TI = The hydrothermal leaching behaviour and properties of sodium-calcium
aluminophosphosilicate glasses
AU = Melling, P.J., Karkhanis, S.N., Fyfe, W.S., Bancroft, G.M. (Chem. Dept.,
Univ. of Western Ontario, London, Ontario, Canada)
SO = Glass Technol. (GB), 192-7, vol.24, no.4, Aug. 1983
AB = Glasses based on a mixture of the minerals tourmaline, bentonite, and
apatite (calcium phosphate) have been prepared. These glasses can be
tailored to produce leach solutions that will readily precipitate
apatites and clay minerals or zeolites. The leaching properties of a
glass containing Cs, Sr, and U have been studied in the presence of a
geochemical buffer of apatite and bentonite. The leaching of Sr and Cs
is significantly retarded in the buffer. A nuclear waste form of glass
of the composition 20CaO-6P/sub 2/O/sub 5/-8B/sub 2/O/sub 3/-10Na/sub
2/O-34SiO/sub 2/-15Al/sub 2/O/sub 3/-3Fe/sub 2/O/sub 3/-10CuO with a
melting temperature of about 1000 degrees C is proposed.
+
62/ 120
TI = Surface electric fields of tourmaline
AU = Yamaguchi, S. (Yamaguchi-Lab., Tokyo, Japan)
SO = Appl. Phys. A (Germany), 183-5, vol.A31, no.4, Aug. 1983
AB = The N/sub 2/, O/sub 2/, H/sub 2/O, and CO/sub 2/ molecules that have
condensed on the surface of a pyroelectric tourmaline crystal were
degassed successively by means of electron bombardment. The temperature
dependence of the electrostatic field strength on the specimen surface
was observed by electron diffraction; it decreased as the degassing
advanced. The tourmaline surface behaved as a gas chromatographic
adsorbent.
+
63/ 120
TI = Tourmaline as gas detection sensor
AU = Yamaguchi, S. (Yamaguchi-Lab., Tokyo, Japan)
SO = Mater. Chem. & Phys. (Switzerland), 493-8, vol.8, no.5, May 1983
AB = The phenomenon that the electric poles of pyroelectric tourmaline
crystals are neutralized by adsorbing gas molecules and ions has been
used for gas analysis. It has been demonstrated in terms of electron
diffraction that a tourmaline surface behaves as a gas chromatographic
sensor.
+
64/ 120
TI = Temperature dependence of the pyroelectric coefficient of polar
dielectrics
AU = Novik, V.K., Bochkov, B.G., Gavrilova, N.D., Drozhdin, S.N.
SO = Pis'ma v Zh. Tekh. Fiz. (USSR), 988-92, vol.8, no.15-16, Aug. 1982
AB = The authors measured the pyroelectric coefficients of some classical
pyroelectrics-tourmaline and some group A/sup II/B/sup VI/ crystals
(ZnO, CdS, and BeO)-by the static method.
+
65/ 120
TI = Mechanisms of Nappe emplacement at the southern margin of the Damara
Orogen (Namibia)
AU = Weber, K., Ahrendt, H. (Geologisch-Palaontologisches Inst., Gottingen,
Germany)
SO = Tectonophysics (Netherlands), 253-74, vol.92, no.1-3, 1983
AB = The Naukluft nappe complex is exposed approximately 50 km south of the
present southern margin of the late Precambrian to early Palaeozoic
Damara Orogen. This nappe complex overlies the autochthonous Nama beds
which belong to a platform area adjacent to the Damara mobile belt. The
total displacement from the NW to the SE amounts to 50-80 km. The base
of the Naukluft nappes is formed by a dolomite horizon ranging in
thickness between zero and about 30 m. Recent investigations of the
mineral content, fluid inclusions, grain fabric, and deformation lead to
the conclusion that continental playa-lake evaporites must be assumed as
source rocks of this dolomite. This unit, named the 'Sole Dolomite'
contains 35 different minerals with sparitic dolomite, albite, quartz,
tourmaline, Mg-riebeckite, talc, and sericite being the main components.
The Sole Dolomite is interpreted as a discordant intrusion under high
pore fluid pressure into the base of a nappe sequence. It may be assumed
that before its lithification the water-rich carbonate mush has acted as
a lubricant. The final displacement of the nappes with the Sole Dolomite
at its base must have taken place after lithification of the intrusion.
Otherwise, the intense low temperature mylonitisation of the
autochthonous and parautochthonous Nama Limestones cannot be explained
adequately.
+
66/ 120
TI = Fluid effects and response in transverse impact on liquid-filled tubes
AU = Katsamanis, F., Goldsmith, W. (Naval Coll., Athens, Greece)
SO = Exp. Mech. (USA), 245-55, vol.22, no.7, July 1982
AB = Two long tubes each of aluminum and polymethyl methacrylate, with two
different wall thicknesses, were subjected to transverse impact by two
different steel spheres when in an empty or a fluid-filled condition.
Water and a high-density electric capacitor liquid were emplaced in the
interior, usually under stationary, but occasionally under streaming,
conditions. Input-force history and response of the system at two gage
stations involving single axial and hoop, as well as coupled symmetric
and antisymmetric strain histories, were recorded from the response of
strain gages, while fluid pressures were measured by means of small
tourmaline crystals suspended at the tube center line. The effect of
parameter variation in input and system material and geometry on these
quantities was studied. The measured signal speed and frequency of the
breathing mode of the system were compared with corresponding analytical
predictions.
+
67/ 120
TI = Pyroelectric Li/sub 2/Si/sub 2/O/sub 5/ glass-ceramics
AU = Gardopee, G.J., Newnham, R.E., Bhalla, A.S. (Materials Res. Lab.,
Pennsylvania State Univ., University Park, PA, USA)
SO = Ferroelectrics (GB), 155-63, vol.33, no.1-4, June 1981
AB = Highly oriented surface layers of lithium disilicate crystals were grown
by crystallizing glasses of the composition Li/sub 2/O:SiO/sub 2/. The
thickness of the oriented layer was a function of the thermal treatment.
The crystallites in these layers were oriented with their c-axis
perpendicular to the sample surface. These layers were found to be
pyroelectric as determined by the Chynoweth technique. The pyroelectric
responses of the glass-ceramics crystallized in a thermal gradient were
approximately four times larger than that of a tourmaline crystal of
similar dimensions.
+
68/ 120
TI = Piezoelectric devices-a step nearer problem-free vibration measurement
AU = Purdy, D.
SO = Transducer Technol. (GB), 24-5, vol.3, no.2, Jan. 1981
AB = Piezoelectric accelerometers have long been established as transducers
suitable for varied vibration measurement applications. They are self
generating, compact, responsive to a wide range of amplitudes and
frequencies, and they also offer rugged and reliable use. The
piezoelectric accelerometer relies on two main features for its
operation. The ability of piezoelectric materials to generate a charge
proportional to their elastic deformation, and a simple mass, spring,
and damper system, possessing a single degree of freedom. Piezoelectric
properties can be found either in natural crystalline materials such as
tourmaline, or they can be introduced into man-made substances. Many
accelerometers use a proprietary piezoceramic PZT-5A-a modified lead
zirconate titanate having a much higher charge sensitivity than natural
crystals, and an upper temperature limit suitable for most requirements.
+
69/ 120
TI = Experimental cavitation studies in a model head-neck system
AU = Lubock, P., Goldsmith, W. (Dept. of Mech. Engng., Univ. of California,
Berkeley, CA, USA)
SO = J. Biomech. (GB), 1041-52, vol.13, no.12, 1980
AB = The response of two different fluid-filled head-neck models to impact
was studied experimentally to provide information concerning the
validity of the widely prevalent cavitation hypothesis of brain damage.
The structures consisted of an acrylic spherical shell with an outside
diameter of about 188 mm and a human calvarium with a clear polyester
resin occiput, representing the head, each coupled to an articulated
artificial viscoelastic neck. Transient phenomena were initiated by the
impact of either cylindrical projectiles fired from a pneumatic gun or
by the pendulum drop of an aluminum spherical shell onto a small
truncated aluminum cone attached to the head models. A short
strain-gaged aluminum cylinder served to measure the input force
histroy, while the pressure in the brain-simulating fluid was
ascertained by means of Z-cut tourmaline crystals located along the
impact axis at the coup, center and contrecoup positions. The occipital
regions of the models were photographed at framing rates of 4000-8000
s/sup -1/ to visually examine the cavitation phenomena. Coup, contrecoup
and resonating cavitation were detected and found to coincide temporally
with negative pressure transients in both head-neck models. These
results lend some support to the cavitation theory as a possible
mechanism for brain damage.
+
70/ 120
TI = Granitization, tectonic cycles, and tin mineralization
AU = Mushenko, L.V., Ognyanov, N.V., Razmakhnina, E.M. (Acad. of Sci.,
Vladivostok, USSR)
SO = Geol. & Geofiz. (USSR), 77-81, vol.20, no.8, 1979
AB = Using the example of the major tin regions of Priamur'e a Primor'e this
article discusses the relationships of mineralization with
pluton-metamorphism and tectonics. It is shown that areas of development
of granitoid rocks correspond to dome structures which appear in the
modern erosion cut as zoned tin-bearing metasomatites. The rear or
central zone of metasomatites is composed of metasomatic potassium
granitoids which have been in the process of formation for a long time.
Commercial deposits are formed against the background of sequential
metasomatic processes due to repeated mineral substitutions with the
gradual accumulation of Sn in the latest rock-forming minerals (biotite
and tourmaline) and its subsequent liberation. In the opinion of the
authors, the change in mineralization and the growth of domes are caused
by the tectonic conditions of compression and expansion with the
appearance in each phase of minerals of different structural looseness (
omega ) and energy stability.
+
71/ 120
TI = Electroelastic effect in tourmaline
AU = Kittinger, E., Seil, K., Tichy, J. (Inst. of Experimental Phys., Univ.
of Innsbruck, Innsbruck, Austria)
SO = Z. Naturforsch. A (Germany), 1352-4, vol.34A, no.11, Nov. 1979
AB = Measuring the electric field induced frequency shift of tourmaline
resonators, the electroelastic constants g/sub 311/ and delta /sub 333/
are determined. These constants may be interpreted as describing either
the electric field dependence of an elastic constant or the stress
(strain) dependence of a piezoelectric constant. Fields up to about
3*10/sup 6/ V/m were used. Within this range the effect is linear and is
of the same order as in alpha -quartz.
+
72/ 120
TI = Mossbauer studies of structural features in tourmaline of various
genesis
AU = Korovushkin, V.V., Kuzmin, V.I., Belov, V.F. (Ministry of Geology,
Bolshaya Grusinskaya, Moscow, USSR)
SO = Phys. & Chem. Miner. (Germany), 209-20, vol.4, no.3, 1979
AB = Nuclear gamma ray (Mossbauer) spectroscopy (ngr) was used to examine 114
samples of tourmaline from different deposits. The absorption curve
shape of the ngr spectra was found to depend not only on tourmaline
composition, but also on the character of cation distribution in the
crystal structure. The complex superpositional nature of the spectra
corresponds to a statistical distribution of iron ions, whereas a
minimum number of doublets is observed in an ordered distribution of
these ions in the structure. The existence of nonequivalent Fe sites
with statistical cation distribution in Y and Z positions was confirmed
by experiments on iron oxidation in tourmaline, temperature studies of
quadrupole splitting, and probability analysis of formation of
nonequivalent sites in accordance with the tourmaline structure.
+
73/ 120
TI = An NGR observation of proton jumps in tourmaline
AU = Pollak, H., Quartier, R., Dauwe, C., Danon, J. (Dept. de Phys., Univ.
Nat. du Zaire, Kinshasa, Zaire)
SO = J. Phys. Colloq. (France), C2/480, vol.40, no.C-2, pt.3, March 1979
AB = Summary form only given, substantially as follows. In tourmaline the
three M-sites share two by two a common edge, thus giving rise to a
common oxygen ion (common point CP). Using symmetry considerations
hydroxyl groups should be disposed as follows: a group at CP and three
groups in the basic plane, such as to respect the trigonal
configuration. Tourmaline commonly contains ferrous as well as ferric
ions. The special investigated specimen only contains ferrous ones. With
increasing temperature spectra, which at liquid helium display a
quadrupole doublet, characteristic for a ferrous ion in octahedral
symmetry, show shoulders on the inner sides of the doublet. As the
temperature still increases, new lines appear with a much smaller
quadrupole splitting but with quite the same isomeric shift. As their
quadrupole splittings show a decrease from He 4K to 600K toward nearly
one half the original value, they should be attributed to the same
ferrous ions in a trans-octahedral site. A proton jump could be the
cause of the observed phenomenon.
+
74/ 120
TI = Elastic constants of tourmaline
AU = Ozkan, H. (Dept. of Phys., Middle East Tech. Univ., Ankara, Turkey)
SO = J. Appl. Phys. (USA), 6006-8, vol.50, no.9, Sept. 1979
AB = Elastic constants of tourmaline crystals of known chemical composition
have been measured by the ultrasonic phase-comparison method. The values
in 10/sup 12/ dyn/cm/sup 2/ are C/sub 11/=3.050, C/sub 33/=1.764, C/sub
44/=0.648, C/sub 66/=0.984, C/sub 14/=-0.06, and C/sub 13/=0.51. The
Debye temperature of the tourmaline derived from the elastic constants
is 785K.
+
75/ 120
TI = Raman spectra of tourmaline
AU = Alvarez, M.A., Coy-Yll, R. (Geology Dept., Univ. of Sevilla, Sevilla,
Spain)
SO = Spectrochim. Acta Vol. A (GB), 899-908, vol.34A, no.9, 1978
AB = Four single crystals of tourmaline lying within the elbaite:
Na(Li,Al)/sub 3/Al/sub 6/B/sub 3/Si/sub 6/O/sub 27/(OH,F)/sub 4/-schorl:
Na(Fe/sup 2+/)/sub 3/Al/sub 6/B/sub 3/Si/sub 6/O/sub 27/(OH,F)/sub 4/
series have been studied. The spectra were recorded at the 100-1200
cm/sup -1/ region. From a dynamical point of view it appears that
tourmaline structure can not be subdivided in separate vibrational
units. It is emphasized that tourmaline must be considered as a
framework lattice.
+
76/ 120
TI = The elastic constants of iron tourmaline (schorl)
AU = Helme, B.G., King, P.J. (Dept. of Phys., Univ. of Nottingham,
Nottingham, England)
SO = J. Mater. Sci. (GB), 1487-9, vol.13, no.7, July 1978
AB = 110 MHz and 1 GHz pulse echo methods have ben used to determine the room
temperature elastic constants of schorl tourmaline characterized by wet
chemical and X-ray analyses.
+
77/ 120
TI = Experimental study of granitic rocks of Darjeeling (West Bengal, India)
and its application to the origin of Himalayan granites
AU = Ghose, N.C., Singh, N.K. (Dept. of Geology, Patna Univ., Patna, India)
SO = Tectonophysics (Netherlands), 23-40, vol.43, no.1-2, 15 Nov. 1977
AB = Phase relationships of a granite and a gneiss from Darjeeling have been
determined at 4 and 7 kbar pressure in the presence of excess water. The
new data demonstrate that crystal-liquid equilibria played a dominant
role in the formation of magmas of granodiorite to granite to pegmatite,
the sequence of which is also established in the field. The anatectic
magma left behind a more desiccated refractory rock now occurring as
hornblende or pyroxene granulites. The granites of the Lower Himalaya
are formed relatively at a lower temperature and pressure than the
younger leucocratic tourmaline granites of the Higher Himalaya.
+
78/ 120
TI = Anomalous pyroelectric behavior in the leaves of the palm-like plant
Encephalartos Villosus
AU = Lang, S.B., Athenstaedt, H. (Dept. of Chem. Engng., Ben-Gurion Univ. of
Negev, Beersheva, Israel)
SO = Ferroelectrics (GB), 511-19, vol.17, no.3-4, 1978
AB = Quantitative pyroelectric measurements were made on the epidermis of the
leaves of the palm-like plant Encephalartos Villosus. The average value
of the pyroelectric coefficient was 0.0129+or-0.0043 mu C m/sup -2/
K/sup -1/ at 298K, about two orders of magnitude smaller than that of
tourmaline. Imposition of a DC bias electric field of 2.7 kV cm/sup -1/
increased the pyroelectric coefficients by a factor of between 10 and
50. Applications of fields as great as 18.2 kV cm/sup -1/ did not
reverse the polarity of the samples, proving that the material is not
ferroelectric. The bias field-induced pyroelectric effect was explained
by means of a non-linear theory. A stress-induced non-linear
pyroelectric effect was also observed.
+
79/ 120
TI = Microwave acoustic relaxation absorption in iron tourmaline
AU = Helme, B.G.M., King, P.J. (Dept. of Phys., Univ. of Lancaster,
Lancaster, England)
SO = J. Phys. (France), 1535-40, vol.38, no.12, Dec. 1977
AB = Microwave acoustic absorption measurements have been made on dark green
schorlite tourmaline at 580 MHz and 1.03 GHz and as a function of
temperature between 1.5K and 300K. In addition to thermal-phonon
attenuation, two large low temperature peaks are found. These peaks are
most pronounced for transverse wave propagation and are found together
or individually, depending on the mode propagated. The data has been
analysed on a simple relaxation model and energy level separations of
14.4+or-0.2 cm/sup -1/ and 42.2+or-0.6 cm/sup -1/ have been deduced from
the form of the two absorption peaks. These figures are confirmed by
far-infrared spectroscopy. It is tentatively suggested that the peaks
may be caused by Fe/sup 2+/ ions on distorted octahedral sites.
+
80/ 120
TI = Investigations on the formation of tracks in crystals
AU = Sigrist, A., Balzer, R. (Lab. fur Kernphys., Eidgenossische Tech.
Hochschule, Switzerland)
SO = Radiat. Eff. (GB), 75-6, vol.34, no.1-3, 1977
AB = The minimal energy loss (dE/d xi )/sub k/ (MeV cm/sup 2//mg) for the
formation of a track in an insulator has been determined for mica,
tourmaline, quartz glass, quartz crystal, lithium niobate and beryl. The
investigations show that the (dE/d xi )/sub k/ value of a track detector
can be roughly estimated from the thermal conductivity of the given
material.
+
81/ 120
TI = Structural mechanism of pyroelectricity in tourmaline
AU = Donnay, G. (Dept. of Geological Sci., McGill Univ., Montreal, Quebec,
Canada)
SO = Acta Crystallogr. Sect. A (Denmark), 927-32, vol.A33, pt.6, 1 Nov. 1977
AB = Pyroelectricity in tourmaline, known since antiquity, was ascribed by
von Boguslawski to a charged, asymmetric, anharmonic oscillator based on
the Einstein model of a crystal. His predicted values of the
pyroelectric coefficient k were in good agreement with Ackermann's
measurements in the range 200-400K. Boguslawski's model has been tested
by refining the structure, at 193 and 293K, on a sphere of gem-quality
elbaite. The pyroelectric effect is due primarily to the asymmetric
anharmonic vibrations of O(1), the oxygen atom of point symmetry 3m
which has a polar environment. Its centre of gravity moves 0.005 AA from
193 to 293K. It is the only atom with a displacement well above
experimental uncertainty.
+
82/ 120
TI = Fission track etching and annealing of tourmaline
AU = Lal, N., Parshad, R., Nagpaul, K.K. (Dept. of Phys., Kurukshetra Univ.,
Kurukshetra, India)
SO = Nucl. Track Detect. (GB), 145-8, vol.1, no.2, June 1977
AB = The annealing behaviour of fission tracks is an important parameter to
make the fission track dates of any mineral to be meaningful. After the
etching conditions of tourmaline were established by Fleischer and Price
(1964), no fission track worker has reported about the thermal
retentivity of fission tracks in tourmaline, which forms the subject
matter of the present note and where etching conditions are different
from those reported by Fleischer and Price (1964).
+
83/ 120
TI = Mineralogy of beach and dune sands of Morgim-Arambol beach on Goa coast
AU = Kidwai, R.M., Wagle, B.G. (Nat. Inst. of Oceanography, Dona Paula,
India)
SO = Indian J. Mar. Sci., 128-30, vol.4, no.2, Dec. 1975
AB = Mineralogic studies of the sand of dune and beach at Morgim-Arambol
indicate that opaques, garnet, staurolite, epidote, chlorite,
bluish-green hornblende, tourmaline, augite-diopside, hypersthene and
zircon are the principal heavy minerals. Three mineral associations are
recognized on the basis of their relative abundance and distribution on
the beach: (i) garnet-epidote-staurolite rich association, (ii)
garnet-epidote-staurolite-chlorite rich association, and (iii)
opaque-garnet-zircon rich association. As the sediments are texturally
similar throughout the beach and as there is no marked areal
mineralogical sorting of the size, shape and specific gravity, this
mineral distribution appears to be controlled by the variations in
source rocks in the drainage basins of the rivers.
+
84/ 120
TI = Investigation of the formation of tracks in crystals
AU = Sigrist, A., Balzer, R. (Lab. fur Kernphys., ETH, Zurich, Switzerland)
SO = Helv. Phys. Acta (Switzerland), 49-64, vol.50, no.1, 4 Feb. 1977
AB = The minimal energy loss (dE/d xi )/sub k/ (MeV.cm/sup 2/.mg/sup -1/) for
the formation of a track in an insulator has been determined for mica,
tourmaline, quartz glass, quartz crystal, lithium niobate and beryl. The
investigations show that the (dE/d xi )/sub k/-value of a track detector
can be roughly estimated from the thermal conductivity of the given
material.
+
85/ 120
TI = Etch figures and crystal structures
AU = Wooster, W.A. (Brooklyn Crystallographic Lab., Cambridge Univ.,
Cambridge, England)
SO = Krist. & Tech. (Germany), 615-23, vol.11, no.6, 1976
AB = The etch figures on some of the naturally occurring faces of crystals of
sodium chloride, cuprite, alpha-quartz, tourmaline and topaz are
compared with the atomic arrangements on the etched surfaces. The etch
figures are influenced in their shape and orientation relative to the
natural faces by a number of factors. One of these factors is the
crystal structure. In every example of an etched pit bounded by straight
edges, it was found that there exists in the crystal structure a
continuous chain of relatively strong inter-atomic bonds, running
parallel to the straight edge. The study of tourmaline indicates the
direction in which all the SiO/sub 4/ tetrahedra are pointing relative
to the external form.
+
86/ 120
TI = Ceramic models for study of piezoelectricity in solids (bone and tendon)
AU = Williams, W.S., Breger, L., Johnson, M. (Materials Res. Lab., Univ. of
Illinois, Urbana-Champaign, Urbana, IL, USA)
SO = J. Am. Ceram. Soc. (USA), 415-17, vol.58, no.9-10, Sept.-Oct. 1975
AB = The piezoelectric behavior of certain biological materials (bone and
tendon) was studied by comparing them with well-understood piezoelectric
ceramics (quartz and tourmaline). The results show that, whereas the
ceramic model materials conform to the standard theory of the
piezoelectricity in both compression and bending, the organic materials
deviate quantitatively and qualitatively in bending. An extension of the
formal theory is developed to include a polarization proportional to the
gradient of the stress and yields predictions in accord with the
experimental findings for bone and tendon. Implications for transducers
competing with electrical ceramics are noted.
+
87/ 120
TI = Effects of gamma-irradiation on the ultrasonic attenuation in quartz and
tourmaline at low temperatures
AU = Thuraisingham, M.S., Stephens, R.W.B. (Imperial Coll., London, England)
SO = Proceedings of the 5th International Conference on Internal Friction and
Ultrasonic Attenuation in Crystalline Solids, 308-13, X+458, 1975
PU = Springer-Verlag, Berlin, Germany
AB = The overall attenuation behaviour for both quartz tourmaline has been
found to follow closely the predictions of Silverman's theory (1968).
The results appear to confirm his basic postulate that the effect of
irradiation is to introduce scattering centres into the crystal and
lower the thermal phonon relaxation time, thereby influencing the
ultrasonic attenuation. Furthermore, the power law relating attenuation
and temperature has been shown to be influenced by irradiation. The
associated velocity changes that were observed appear to suggest that
the attenuation is influenced via the elastic properties of the crystal.
+
88/ 120
TI = Gamma ray irradiation induced changes in the color of tourmalines
AU = Nassau, K. (Bell Labs., Murray Hill, NJ, USA)
SO = Am. Mineral. (USA), 710-13, vol.60, no.7-8, July-Aug. 1975
AB = Color changes were observed on gamma ray irradiation of over 500
colorless, pink, blue, and green tourmalines. The only significant
changes observed were the development or intensification of pink or the
development of yellow superimposed on the preexisting color. Irradiation
and heating indicates the possibility of at least seven causes of pink
and two causes of yellow colors in tourmaline; some of these colors are
stable to heat, and some are not. This complexity may explain the
diversity of previous assignments for the origin of the pink color.
+
89/ 120
TI = Synthesis of tourmaline in chloride media. II
AU = Voskresenskaya, I.E., Kovyzhenko, N.A., Shternberg, A.A. (Inst. of
Crystallography, Acad. of Sci., USSR)
SO = Kristallografiya (USSR), 210-13, vol.20, no.1, Jan.-Feb. 1975
AB = For pt.I see ibid., vol.18, p.562, 1974. Following work on Mg and Fe
tourmalines, the growth of Co, Ni, Cr and Mn tourmalines of various
colours in highly concentrated chloride media is described. Refractive
indices, lattice spacings and X-ray line diagrams are given.
+
90/ 120
TI = Isomorphous impurities and free radical formation in minerals (electron
centers and hole centers)
AU = Marfunin, A.S. (Inst. de Geologie des Gites Mineraux, Acad. des Sci.,
Moscow, USSR)
SO = Bull. Soc. Fr. Mineral. & Crystallogr. (France), 194-201, vol.97, no.2,
March-Oct. 1974
AB = As far as trace elements are concerned, all natural minerals are solid
solutions. Substitutional impurities (and interstitial impurities and
vacancies) are point defects that capture electrons of holes during
natural or artificial irradiation. A great number of centers were found
in minerals by using paramagnetic electronic resonance. Models of these
centers are definitely elucidated. The centers are widely present in
rock forming minerals: feldpsars, quartz, zircon, phenacite, topaz,
euclase, kyanite, beryl, sodalite, lazurite, danburite, datolite,
tourmaline, apatite, amblygonite, anhydrite, barytite, celestite,
calcite, aragonite, etc. Periodic systems of these centers in minerals
and inorganic compounds are proposed. A review of the models of centers
and of their petrological applications is given.
+
91/ 120
TI = Pyroelectric properties of tourmaline and cancrinite crystals in a wide
range of temperatures
AU = Drozhdin, S.N., Novik, V.K., Koptsik, V.A., Kobyakov, I.B. (M.V.
Lomonosov Moscow State Univ., Moscow, USSR)
SO = Fiz. Tverdogo Tela (USSR), 3266-9, vol.16, no.11, Nov. 1974
AB = Measurements of the pyroelectric coefficients of tourmaline and
cancrinite crystals between 4.2 and 300K showed an unusual change of
sign at 18K for tourmaline and 56K for cancrinite. Possible mechanisms
are discussed.
+
92/ 120
TI = Manganese ion site distribution studies in tourmaline by anomalous X-ray
scattering methods
AU = Johnston, J.H., Duncan, J.F. (Dept. of Chem., Victoria Univ. of
Wellington, Wellington, New Zealand)
SO = J. Appl. Crystallogr. (Denmark), 469-72, vol.8, pt.4, 1 Aug. 1975
AB = The Mn/sup 3+/ site distribution in a manganese-containing tsilaisite
tourmaline sample has been determined as 46+or-3 wt.% in the larger Y
octahedral sites and 54+or-3 wt.% in the smaller Z octahedral sites. For
this, a novel application of anomalous X-ray scattering techniques, in
conjunction with the energy dispersive X-ray diffraction procedure, has
been used. This method appears to be versatile and applicable to many
different elements.
+
93/ 120
TI = Microsonic attenuation studies of tourmaline
AU = Helme, B.G.M., King, P.J. (Univ. Lancaster, England)
SO = Satellite Symposium of the 8th International Congress on Acoustics on
Microwave Acoustics, 109-12, x+218, 1974
PU = Univ. Lancaster, Lancaster, England
AB = With the exception of the longitudinal wave propagating in the direction
of the c axis all the acoustic modes investigated were found to be
affected by broad relaxation peaks. These peaks extended in some cases
to room temperatures and would adversely affect the performance of
tourmaline as a low loss device material. The evidence is strongly in
favour of the peaks being due to iron since they are not present in low
iron Dravite and the other paramagnetic impurities are present in
quantities likely to give the large effects observed. The analysis of
the peaks indicates that the relaxation is dominated by indirect
processes except at the lowest temperatures. From the relaxation times,
positions for excited states are found which are in good agreement with
those from infra-red data although the low lying levels involved may not
be the same in each case.
+
94/ 120
TI = Underwater impulse measurements
AU = Levin, P.A.
SO = Bruel & Kjaer Tech. Rev. (Denmark), 3-13, no.4, 1974
AB = Investigates the ability of hydrophones to measure shock waves generated
by explosives. The peak pressures and decay rates obtained from time
histories of shock waves registered on the oscilloscope from the
hydrophones are used to compute the energy flux density and impulse per
unit area. The results are in good agreement with those obtained from a
tourmaline transducer normally used for shock measurements.
+
95/ 120
TI = Nonequivalent positions of the iron ions and electron-nuclear
interaction in tourmaline
AU = Belov, V.F., Korovushkin, V.V., Belov, A.F., Korneev, E.V., Zheludev,
I.S. (Inst. Crystallography, Acad. Sci., Moscow, USSR)
SO = Fiz. Tverdogo Tela (USSR), 2410-11, vol.16, no.8, Aug. 1974
AB = A study of the temperature dependence of the quadrupole splitting of the
Mossbauer spectrum of tourmaline is consistent with a structural model
in which the Fe/sup 2+/ ions occupy inequivalent sites in Mg or Al
octahedra.
+
96/ 120
TI = Single crystal growth and optical, elastic, and piezoelectric properties
of polar magnesium barium fluoride
AU = Recker, K., Wallrafen, F., Haussuhl, S. (Univ. Bonn, Germany)
SO = J. Cryst. Growth (Netherlands), 97-100, vol. 26, no. 1, Nov. 1974
AB = Single crystals of MgBaF/sub 4/ of optical quality with dimensions up to
4 cm have been grown by both Bridgman and Czochralski techniques.
Optically clear single cyrstals of MgF/sub 2/ and BaF/sub 2/ were used
in stoichiometric ratio as initial ingots yielding untwinned crystals
fully transparent in the range from 180 to 8000 nm. Optical, dielectric,
elastic, thermoelastic, piezoelectric, pyroelectric, and thermal
properties have been measured. MgBaF/sub 4/ crystals show unusual strong
anisotropic effects. The material exhibits a longitudinal piezoelectric
effect about four times higher than quartz. Also a strong pyroelectric
effect is observed about ten times larger than in tourmaline. The
crystals are suited for ultrasonic and pyroelectric devices, such as
generators and sensors.
+
97/ 120
TI = Pyroelectricity: a 2300-year history
AU = Lang, S.B. (Univ. Negev, Beer-Sheva, Israel)
SO = Ferroelectrics (GB), 231-4, vol.7 no.1-4, 1974
AB = The first description of the pyroelectric effect, probably as observed
in tourmaline, was published by Theophrastus in about 300 B.C.
Pyroelectricity was 'rediscovered' by Dutch gem cutters in 1703 and the
first scientific investigation was published by Aepinus about 50 years
later. A number of qualitative investigations were made in the latter
half of the 18th century, to be followed by many sophisticated
quantitative studies in the 19th and early 20th centuries. The
highlights of the history of pyroelectricity prior to 1960 are described.
+
98/ 120
TI = Synthesis of tourmaline in chloride media. I
AU = Voskresenskaya, I.E., Shternberg, A.A. (Inst. Crystallography, Acad.
Sci., USSR)
SO = Kristallografiya (USSR), 888-90, vol.18, no.4, July-Aug. 1973
AB = Al, Li, Mg and Fe tourmaline crystals were grown by mixing oxides and
hydroxides to the required composition and heating in ampoules at 750
and 800 degrees C and 5-8 kbar for 2-3 hours. Prismatic crystals 0.5-1.5
mm in size were produced. Somewhat larger crystals were obtained by
adding quartz and corundum, boric acid, sodium chloride and crystal
hydrates of other chlorides together with seed crystals of the
tourmaline.
+
99/ 120
TI = Temperature dependence of domains and visibility of inhomogeneities of
single crystals by cathodoluminescence (SEM)
AU = Blaschke, R., Brocker, W., Seidel, P. (Univ. Munster, Germany)
SO = Joint Session on Electron Microscopy (abstracts only received), 26, 103
pp, 1973
PU = Liege Univ., Liege, Belgium
AB = C.L. equipment and the cooling/heating state on STEREOSCAN Mk II were
used to investigate the reversible growth, migration and involution of
domains near the low temperature transition point of sodium niobate. In
spite of a reliable temperature control of the sample holder there are
differences in the transition temperature of single crystals compared to
those determined by X-ray methods. During cooling an increase in
cathodoluminescence yield of about 100 percent at -170 degrees C,
compared with +20 degrees C was observed. Lamellae in low-quartz zonar
composition and radiation damage of tourmaline, decomposition of
lanthanium borate into two coherent phases, inclusion of perovskite in
YAl-garnets and the increasing of C.L. yield and C.L. life-time of
feldspar at low temperatures were also observed.
+
100/ 120
TI = Stereographic projections of surfaces for the physical properties of
crystals
AU = Butabaev, Sh.M., Sirotin, Yu.I. (M.V. Lomonosov Moscow State Univ.,
USSR)
SO = Kristallografiya (USSR), 195-7, vol.18, no.1, Jan.-Feb. 1973
AB = A method is given of drawing indicative surfaces to indicate the
anisotropy in physical proportion of crystals, e.g. thermal expansion,
piezoelectric effect. Diagrams are shown for aragonite and tourmaline.
+
101/ 120
TI = Nuclear magnetic resonance of /sup 1/H, /sup 7/Li, /sup 11/B, /sup 23/Na
and /sup 27/Al in tourmaline (elbaite)
AU = Tsang, T., Ghose, S. (NASA, Greenbelt, Md., USA)
SO = Am. Mineral. (USA), 224-9, vol.58, no.3-4, March-April 1973
AB = /sup 1/H resonance indicates the presence of (OH) groups, but no water
molecules. /sup 7/Li resonance indicates a quadrupole coupling constant
mod e/sup 2/qQ/h mod =0.16 MHz, and a pseudotetragonal symmetry for the
Li/sup +/ ion occurring at the 9(b) site; the axis of distortion is
approximately 45 degrees off the c-axis and coincides approximately with
the octahedral O/sub 1/-Li-O/sub 3/ direction. The /sup 11/B resonances
clearly show the triangular BO/sub 3/ coordination with little deviation
from three-fold symmetry at the boron site; the quadrupole coupling
constant, mod e/sup 2/qQ/h mod =2.76+or-0.08 MHz is comparable to values
obtained for /sup 11/B in BO/sub 3/ triangles found in other borate
minerals. The B-O bond is highly covalent. The /sup 23/Na central
transitions are unshifted within experimental errors; thus the
quadrupole coupling constant is small (<0.2 MHz). The /sup 27/Al
satellites were broad and overlapping. For /sup 27/Al in the distorted
octahedral 18(c) sites, the quadrupole coupling constant is estimated to
be approximately 6 MHz. Weak and broad satellite signals suggest cation
disorders or twinned domains for tourmaline.
+
102/ 120
TI = Microwave ultrasonic attenuation in topaz, beryl, and tourmaline
AU = Lewis, M.F., Patterson, E. (General Electric Co. Ltd., Wembley, England)
SO = J. Appl. Phys. (USA), 10-13, vol.44, no.1, Jan. 1973
AB = Microwave ultrasonic attenuation measurements have been made on single
crystals of topaz, beryl, and tourmaline, and all are found to exhibit
very low losses. The room-temperature attenuation coefficients are
consistent with the Akhiezer mechanism which arises from interactions
between the ultrasonic wave and the thermal-phonon assembly.
+
103/ 120
TI = g=4.3 Isotropic e.p.r. line in tourmaline
AU = Ja, Y.H. (Univ. Sydney, Australia)
SO = J. Chem. Phys. (USA), 3020-2, vol. 57, no. 7, 1 Oct. 1972
AB = An isotropic EPR line with g=4.302+or-0.006 was found in a natural
single crystal of tourmaline. This line can be ascribed to the impurity
Fe/sup 3+/, occupying a host site with the axial field parameter D=0 and
the rhombic field parameter E>>h nu . After an inspection of the
environments of different host-cation sites, it is believed that Fe/sup
3+/ ion replacement of the B/sup 3+/ host site is most likely
responsible for this isotropic line.
+
104/ 120
TI = Assessment of tourmaline as an acoustic-surface-wave-delay medium
AU = Lewis, M.F., Patterson, E. (GEC Ltd., Wembley, England)
SO = Appl. Phys. Lett. (USA), 275-6, vol. 20, no. 8, 15 April 1972
AB = Measurements and calculations have shown tourmaline to be a useful
surface-acoustic-wave-delay medium. In particular, its combination of
high velocity and very low propagation losses, together with a moderate
piezoelectric coupling strength, makes it suitable for use at higher
frequencies than are feasible with quartz or LiNbO/sub 3/.
+
105/ 120
TI = Measurement of the pyrocoefficient in the 40 to 600 C temperature range
AU = Karyakina, N.F., Novik, V.K., Gavrilova, N.D. (Moscow State Univ., USSR)
SO = Pribory Tekh. Eksp. (USSR), 227-30
AB = A high-temperature thermostat and a method of measuring the
pyrocoefficient are described. Results are given of the measurement of
the pyrocoefficient of natural rose tourmaline in the temperature range
40 to 600 degrees C, which coincide with data obtained by other authors.
+
106/ 120
TI = Magnetic susceptibility and triangular exchange coupling in the
tourmaline mineral group
AU = Tsang, T., Thorpe, A.N., Donnay, G., Senftle, F.E. (Howard Univ.,
Washington, D.C., USA)
SO = J. Phys. & Chem. Solids (GB), 1441-8, vol.32, no.7, July 1971
AB = Magnetic susceptibilities of three iron-rich tourmaline crystals from
Mexquitic (Mexico), Pierpont(New York), and Madagascar with different
and known chemical compositions have been studied from 8 degrees to 300
degrees K. The iron atoms in the tourmaline crystal structure, space
group R3m, a approximately 15.9, c approximately 7.2AA, are situated at
the three corners of an equilateral triangle and are close enough for
magnetic exchange interaction. For buergerite, the Mexquitic sample, the
susceptibility data lead to an exchange constant J/k of 7.5 degrees K.
Although the amount of aluminum would be sufficient to fill point
position 18(c) exactly, the magnetic data are consistent with some
substitution of ferric iron for aluminum, as previously determined from
X-ray and neutron diffraction studies. Some aluminum thus replaces iron
in position 9(b). Exchange constants were also estimated for the other
two magnesium-iron specimens, of which the Madagascar sample is aluminum
deficient. The results agree with the evidence from optical spectra that
there is considerable deviation from octahedral symmetry in the oxygen
coordination polyhedra about the 9(b) and 18(c) point positions.
+
107/ 120
TI = Preparation of thin foils of diamond by a fracture technique
AU = Ritter, G.J., Murphy, R.J. (Nat. Phys. Res. Lab., Pretoria, South
Africa)
SO = Proceedings of the 7th international congress on electron microscopy,
331-2, xxxii+674, 1970
PU = Soc. Francaise de Microscopie Electroniques, Paris, France
AB = The preparation of electron microscope samples from a specimen in which
the material of interest is in the form of transparent micro- inclusions
in a polished face of a mineralogical specimen presents a number of
problems. A method which makes use of the focused output from a laser to
initiate fracture in such inclusions or in isolated grains has been
successfully applied to prepare electron microcope samples from a number
of minerals including diamond, zircon and tourmaline. Graphite is formed
about the focal spot located inside the diamond when laser pulses with
peak powers of 3-4 MW and half intensity widths of about 80 nanoseconds
from a Q-switched laser are used.
+
108/ 120
TI = Measurement of particle velocity at a shock front in water with a laser
Doppler meter
AU = Anderson, R.E., Edlund, C.E., Vanzant, B.W. (Southern Res. Inst., San
Antonio, Tex., USA)
SO = J. Appl. Phys. (USA), 2741-3, vol. 42, no. 7, June 1971
AB = A laser Doppler meter was used to detect particle motion in tap water
due to the passage of an explosively generated shock front. It was not
necessary to introduce foreign particles or dust in the region of
observation to serve as scattering centres. Optics of the system were
aligned such that particle motion was monitored in only small volume
rather than over the entire ray path length. Particle velocities
measured with the Doppler system were in agreement with those calculated
from the response of a standard tourmaline piezoelectric pressure gauge
placed adjacent to the region on which the Doppler meter was focused.
+
109/ 120
TI = A new crystal habit of tourmaline
AU = De Camargo, W.G.R., Souza, I.M. (Univ. Sao Paulo, Brazil)
SO = An. Acad. Brasil. Cienc., 219-22, vol.42, no.2, 1970
AB = Tourmaline crystallized as porphyroblasts embedded into a chloriteschist
is investigated. The crystals which are not oriented according to the
schistosity of matrix rock, have dimensions of a few centimeters, dark
color, strong pleochroism in thin section, and indices of refraction
omega =1.652: epsilon =1.631. The main crystal forms are (1 0 1 0), (0 1
1 0), (1 0 1 2) and (1 0 1 2 ), the latter being responsible for the
pseudomonoclinic habit of the individuals, which are roughly resembling
to amphibole crystals. The unit cell, as measured by the X-ray
diffraction powder technique has the following dimensions: a/sub
o/=15.96+or-0.01 AA and c/sub o/=7.209+or-0.003 AA, with an axial ratio
of c/a=0.4517. The crystallographic data, together with the optical
properties, classify the tourmaline as dravite.
+
110/ 120
TI = On the dichroism of tourmaline
AU = Townsend, M.G. (Dept. Energy, Mines, Resources, Ottawa, Canada)
SO = J. Phys. Chem. Solids (GB), 2481-8, vol.31, no.11, Nov. 1970
AB = The dichroism of tourmaline arises partially from charge-transfer
transitions within next-nearest neighbour cations through shared
octahedral edges in the 001 layer. Similar structural features occur in
the sheet silicates, and charge-transfer spectra in these structures are
discussed.
+
111/ 120
TI = Magnetic properties of the tourmaline group
AU = Tsang, T., Thorpe, N., Senftle, F.E., Donnay, G. (Howard Univ.,
Washington, D.C., USA)
SO = American Crystallographic Association Summer meeting (abstracts), 78,
96, 1970
PU = American Crystallographic Association, Pittsburgh, Pa., USA
AB = Abstract only given substantially as follows. Tourmalines free from iron
and manganese can only be paramagnetic, whereas those tourmalines
containing magnetic ions can be expected to show evidence of magnetic
exchange interactions. Magnetic susceptibilities of three iron-rich
tourmaline crystals of different, known, chemical compositions have been
studied from 8 degrees to 300 degrees K. One sample studied is a
ferric-oxytourmaline or buergerite, which may be described from a
magnetic viewpoint as having isolated triangles with Fe/sup 3+/ ions at
the corners. Its exchange constant J/k=7.5 degrees K may be derived from
the measured susceptibility data. The susceptibility measurements are
also consistent with the X-ray and spectral evidence that, in spite of
the presence of just enough aluminum to fill the Al position, a small
fraction (8%) of Fe/sup 3+/ ions are substituting for aluminum. From the
other two tourmaline samples, an iron-rich, aluminum-deficient specimen
from Madagascar, and a magnesium-iron specimen from Pierpont, N.Y., it
is possible to estimate the exchange interactions between the iron atoms
substituting for aluminum atoms.
+
112/ 120
TI = Rooseveltite from San Francisco de los Andes, San Juan, Argentina
AU = Bedlivy, D., Llambias, E.J., Astarloa, J. (Univ. Buenos Aires,
Argentina)
SO = 8 International congress of crystallography (abstracts), 1pp., iv+295,
1969
PU = American Inst. Phys., New York, USA
AB = Abstract only given, substantially as follows: The hypogene
mineralization consisting of pyrite, arsenopyrite, bismuthinite,
chalcopyrite, sphalerite, and luzonite is located in the peripheral zone
of a tourmaline breccia-pipe. Rooseveltite is mainly associated with an
unknown Bi-arsenate, conichalcite, olivenite, clinoclase, scorodite,
beudantite and bismutite. Rosseveltite appears in gray grains of less
than 5 mu as pseudomorphs after bismuthinite. The synthetic compound was
prepared after A. de Schulten at a pH of about 0.1. Its powder pattern
is identical with that of the mineral. After heating to 900 degrees C,
no variations were observed, in the powder diagrams of both mineral and
artificial compound. The synthetic material melts at about 950 degrees
C. Rooseveltite is monoclinic, with a/sub 0/=6.87+or-0.02 A, b/sub
o/=7.15+or-0.05 A, c/sub o/=6.73+or-0.02 A, beta =104 degrees
50'+or-30', space group C/sub 2h//sup 5/-P2/sub 1/c, V=320 A/sup 3/,
Z=4, rho /sub calc./=7.23 gcm/sup -3/. Data were obtained from
single-crystal precession photographs and powder patterns. The 15
strongest lines and their intensities for the mineral are given.
+
113/ 120
TI = The crystal structure of axinite revised
AU = Ito, T., Takeuchi, Y., Ozawa, T., Araki, T., Zoltai, T., Finney, J.J.
SO = Proc. Japan. Acad., 490-4, vol.45, no.6, June 1969
AB = The crystal structure of axinite, H(Fe, Mn)Ca/sub 2/Al/sub 2/BSi/sub
4/O/sub 16/, was investigated by Ito and Takeuchi (1952) on the
assumption that boron atoms in the structure form separate BO/sub 3/
groups like tourmaline. Since axinite is one of those common silicate
minerals whose crystal structure has not been refined, the authors have
thoroughly reinvestigated using modern techniques.
+
114/ 120
TI = Infrared reflection spectrum of tourmaline
AU = Vierne, R., Brunel, R.
SO = C.R. Acad. Sci. B (France), 488-90, vol. 270, no.7, 16 Feb. 1970
AB = The study of the infrared reflection in polarized light of two
tourmalines has enabled BO/sub 3/ triangles to be identified in the
vibration spectra confirming therefore the existence of such triangles
and not of tetrahedral BO/sub 4/ in these crystals.
+
115/ 120
TI = Features of radiative colour centres and microisomorphism in crystals
AU = Samoilovich, M.I., Tsinober, L.I.
SO = Kristallografiya (USSR), 755-66, vol.14, no.4, 1969
AB = Investigations on radiational colour centres in minerals are reviewed,
with special reference to the application of the latest methods of
electron paramagnetic resonance and optical spectroscopy. The close
connection between colour centres and various kinds of microisomorphic
replacement in crystals is discussed. Progress in developing the theory
of molecular orbits, particularly in their application to ion radicals,
makes it possible to link EPR and spectroscopic data. Colour centres in
quartz, calcite, tourmaline, danburite, aragonite, barite, celestine,
amblygonite, apophyllite, apatite, fluorophlogopite, scapolite, and a
number of other materials are discussed with regard to the features of
their impurity composition. It is shown that the entry of impurities in
structural form into the crystal causes a redistribution of charge,
leading to regions of uncompensated charge in the lattice which capture
electrons and holes and thus form colour centres.
+
116/ 120
TI = Investigation of tourmalines by the infrared spectroscopy method
AU = Plyusnina, I.I., Granadchikova, B.G., Voskresenskaya, I.E.
SO = Kristallografiya (USSR), 450-5, vol.14, no.3, 1969
AB = Results are reported of measurements of the infrared spectra of natural
and synthetic schorlite, dravite, and elbaite. It is shown that
isomorphous replacement of Al by Si occurs in the tourmaline structure,
particularly in elbaite, which contains large quantities of Al. The main
diagnostic criteria for determining the variety of tourmaline are found
to be the position of the fundamental bands in the absorption spectra,
and the positions of the B/sup III/-O and OH-valence bands.
+
117/ 120
TI = Pyroelectric detection of X-ray absorption by tourmaline
AU = Bose, D.N., Henisch, H.K., Toole, J.M. (Materials Research Lab., The
Pennsylvania State Univ., USA)
SO = Solid-State Electronics (GB), 65-8, vol.12, no.2, Feb. 1969
AB = It is shown that the pyroelectric properties of tourmaline may be used
for the measurement of large X-ray doses. The pyroelectric voltage
across a specimen subjected to uniform heating between 300-600 degrees K
goes through a maximum which is dependent upon the previously received
X-ray dose. This behavior is correlated with thermally stimulated
current measurements. The sensitivity is low but the storage capacity
high ( approximately 10/sup 5/R). At room temperature the energy stored
does not decay measurably over periods of 2 weeks. Effects of neutron
bombardment are also discussed.
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TI = The crystal field spectra and dichroism of tourmaline
AU = Wilkins, R.W.T., Farrell, E.F., Naiman, C.S. (Dept. Geological Sci.,
Harvard Univ., Cambridge, Ma., USACenter for Materials Sci. and
Engineering and Dept. Electrical Engineering, M.I.T., Cambridge, Ma.,
USAMITHRAS, Div. of Sanders Associates, Cambridge, Ma., USA)
SO = J. Phys. Chem. Solids (GB), 43-56, vol. 30, no. 1, Jan. 1969
AB = Optical absorption spectra of colorless, pink, green, blue, brown and
black tourmaline have been taken to determine the origin of the colors
and to explain the color changes which occur on heating. Absorption data
were taken with polarized radiation parallel and perpendicular to the c
axis at 77 and 300 degrees K. Cell dimensions supported by partial
chemical analyses were used to characterize the specimens. The data
combined to show that generally speaking the color is due to electronic
transitions in and the amount of Fe/sup 2+/, Fe/sup 3+/ and Mn/sup 2+/
in the crystal. Specimens on the dravite-schorl join are
characteristically colored shades of brown. With small to moderate
concentrations of transition metal ions, colors on the elbaite-schorl
join are clear pinks, greens and blues according to the Fe/sup
2+//(Fe/sup 2+/+Fe/sup 3+/+Mn/sup 2+/) ratio in the tourmaline.
Intensity changes of absorption peaks and shifts in the absorption
edges, correlated with removal of hydrogen and consequent oxidation of
Fe/sup 2+/ to Fe/sup 3+/ in the structure account for color changes
observed when tourmaline is heated in air. Blue tourmaline becomes green
on short-term heating and redish-brown on further heating. Assignments
of absorption peaks from 0.3 to 2.0 mu to specific transitions in the
appropriate cations have been made and the origin of the characteristic
dichroism is discussed.
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TI = A gas-actuated acoustic dilatometer for thermal expansion measurements
on metals
AU = Goring, G.E. (Engineering Sci. Dept., Trinity Univ., San Antonio, Tx.,
USA)
SO = J. Sci. Instrum. (J. Phys. E) (GB), 137-42, Ser. 2. vol.2, no.2, Feb.
1969
AB = Thermal expansion properties of metals have been measured to five
significant figures with a gas-actuated acoustic dilatometer, utilizing
an X-cut quartz crystal driven at resonance by a 600 kHz signal.The
technique has been demonstrated up to 450 degrees c on type 304 steel
and the results agree well with known characteristics of this metal.
Planned extension of the method to higher temperatures ( approximately
1200 degrees c) will require substitution of a tourmaline crystal whose
Curie point lies above this range.
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TI = Colour centres in lithium tourmaline (elbaite)
AU = Bershov, L.V., Martirosyan, V.O., Marfunin, A.S., Platonov, A.N.,
Tarashchan, A.N.
SO = Kristallografiya (USSR), 730-2, vol.13, no.4, July 1968
AB = The spectra of electron paramagnetic resonance, luminescence, and
absorption are determined for elbaite (composition Na(Li, Al)/sub
3/Al/sub 6/B/sub 3/.(Si/sub 6/O/sub 18/)(OH, F)/sub 4/). Results are
compared for the natural and gamma- irradiated material, and the
conditions for bleaching are established. The observations are discussed
in relation to the structure, and to the existence of paramagnetic and
luminescence centres in the elbaite.
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