Results 111 to 120 of about 194 (151)
Some of the next articles are maybe not open access.
The crystal chemistry of stilbites and stellerites
Bulletin de Minéralogie, 1978A total of 65 samples of stilbite and stellerite have been chemically analyzed and X-rayed. By using F-unit cell also for monoclinic stilbites, the lattice constants ranges are : a = 13.570-13.605 Â, b = 18. 198-18.270 Â, c = 17.823-17.863 Â for stellerites, and a = 13.595-13.657 À, b = 18. 197-18.309 Â, c = 17.775-17.842 Â, β = 90.
Passaglia, Elio +3 more
openaire +2 more sources
Microporous Stilbite single crystals for alcohol sensing
Journal of Electroceramics, 2006The possibility of shape-selective resistive gas sensors for polar molecules using the microporous alumo-silicate Stilbite is investigated. The electrical impedance of natural Stilbite single crystals at 80°C decreases in presence of methanol, 2-propanol and 3-pentanol, but increases with increasing water and neo-pentanol vapour pressure.
Schäf, O. +3 more
openaire +1 more source
Stilbite-laumontite equilibrium
Contributions to Mineralogy and Petrology, 1971The reaction stilbite=laumontite+3 quartz+3 H2O was experimentally studied using conventional hydrothermal techniques employing mineral mixtures consisting of reactants and products in 9∶1 and 1∶9 ratios. Equilibrium was demonstrated; the univariant curve passes through about 170° C and 2000 bars, 185°±10° C and 3000 bars, about 185° C and 4000 bars ...
openaire +1 more source
Synthesis of stilbite by the hydrothermal method
Journal of Physics D: Applied Physics, 1998The effect of temperature on stilbite synthesis was investigated systematically in the temperature range 80-C by hydrothermal treatment of artificial glasses of the same composition (1O-8CaO-9O) at 1 kbar O pressure. The zeolite was always formed with monoclinic symmetry (, a = 13.61 A, b = 18.24 A, c = 11.27 A and ; or , a = 13.61 A, b = 18.24 A, c ...
H Ghobarkar, O Schäf
openaire +1 more source
ChemInform Abstract: New Zeolite Derivatives of Stilbite.
ChemInform, 1988AbstractThe natural zeolitic mineral stilbite and its Ag(I) exchanged form are tested for their suitability as cation exchangers and as adsorbents for CO2, H2S, and NH3.
N. SINGHAI, S. P. BANERJEE
openaire +1 more source
Stellerite and Stilbite from Pennsylvania Trap Rocks
Rocks & Minerals, 2019In the late Triassic to early Jurassic, about 220 million years ago, North America began to separate from Africa and Europe as the ancient supercontinent of Pangea broke up and the Atlantic Ocean f...
Peter B. Leavens +2 more
openaire +1 more source
THERMAL TRANSFORMATIONS OF STILBITE
Canadian Journal of Earth Sciences, 1966Stilbite samples from two localities were examined. Preliminary D.T.A. and T.G.A. investigations to 1 400 °C were followed by high temperature diffractometry. Debye–Scherrer and Guinier techniques were used to study cooled samples, Diffractometer and single crystal data were processed with a computer to calculate cell parameters and thermal expansion ...
openaire +1 more source
Solid solutions of stilbite and epistilbite
Inorganic Materials, 2015Analysis of the empirical compositions of stilbite-Ca and epistilbite from various occurrences has shown that these solid solutions differ primarily in the mole fraction of water in their compositions. A comparative analysis of different structural models of stilbite (C2/m, F 2/m (42℃), and Amma (168℃)) revealed no fundamental distinctions between the ...
openaire +1 more source
2. Stilbite, from Kerguelen's Island
Proceedings of the Royal Society of Edinburgh, 1882I am indebted to the kindness of my friend Mr J. Y. Buchanan, M.A., the chemist and physicist to the “Challenger” expedition for the specimen which forms the subject of this note.In speaking of the geology of Kerguelen Island, Mr Buchanan thus describes the occurrence of this zeolite (vide Proc. Roy. Soc., vol. xxiv. p.
openaire +1 more source
Thermochemical study of calcium zeolites—heulandite and stilbite
American Mineralogist, 2001Calorimetric measurements were made on natural samples of heulandite having the composition Ca0.86Na0.37K0.06Al2.14Si6.86O18·6.1H2O and stilbite Ca1.01Na0.12Al2.12Si6.88O18·7.27H2O both from the same locality (Nidym River, E. Siberia, Russia). Enthalpies of formation and hydration were studied by calorimetry in lead borate solvent at 975 K.
I. Kiseleva +3 more
openaire +1 more source