搜索结果: 1-15 共查到“凹凸棒石 MAS NMR”相关记录18条 . 查询时间(0.049 秒)
Solid-state 29Si MAS NMR studies of illite and illite-smectite from shale
Solid-state 29Si MAS NMR studies illite illite-smectite shale
2012/4/1
A new method to extract quantitative information from poorly resolved Si magic-angle spinning
(MAS) nuclear magnetic resonance (NMR) spectra of natural mixed-layer illite-smectite (I-S) clays29Si
i...
Local Ca-Mg distribution of Mg-rich pyrope-grossular garnets synthesized at different temperatures revealed by 29Si MAS NMR spectroscopy
Local Ca-Mg distribution Mg-rich pyrope-grossular garnets synthesized different temperatures revealed 29Si MAS NMR spectroscopy
2012/4/1
Pyrope-grossular solid solutions, (Mg,Ca) Al Si O , of composition Py Gr and Py Gr were3 2 3 12 85 15 75 25
synthesized at 1000, 1200, and 1400 ?C and 30 kbars in a piston-cylinder device. The synt...
Three- and five-quantum 17O MAS NMR of forsterite Mg2SiO4
Three- and five-quantum 17O MAS NMR forsterite Mg2SiO4
2012/3/31
17Three- and five-quantum O MAS NMR experiments are used to resolve fully the three crystallo-
graphically distinct oxygen species in forsterite (Mg
SiO ). The chemical shift and quadrupolar pa-2 4...
23Na, 29Si, and 71Ga MAS-NMR spectroscopy of synthetic gallian-fluor-amphiboles
synthetic gallian-fluor-amphiboles magic-angle-spinning nuclear magnetic resonance
2012/3/31
A magic-angle-spinning nuclear magnetic resonance (MAS NMR) spectroscopic study was done
on the series of synthetic gallian-fluor amphiboles to identify the extent of Ga and Si ordering in the
Si MA...
Si,Al ordering in the double-ring silicate armenite, BaCa2Al6Si9O30?H2O: A single-crystal X-ray and 29Si MAS NMR study
BaCa2Al6Si9O30?H2O single-crystal
2012/3/30
29The SiMASNMRspectrumofarmenitefromWasenalp(Valais,Switzerland)indicates
completeSi,Alordering.Thesamechemicalshifts(82.3,95.0,and101.8ppm)were
alsomeasuredforarmenitefromRe!migny(Quebec,Canada),ho...
Effects of Secondary Iron Phases on Kaolinite 27Al MAS NMR Spectra
27Al NMR Spectroscopy Goethite Halloysite Hematite Iron Kaolinite Magnetic Susceptibility
2011/12/8
Abstract: Eight kaolinite and 2 halloysite samples were analyzed using 27Al magic angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy, chemical analysis and magnetic susceptibility to und...
29Si MAS NMR systematics of calcic and sodic-calcic amphiboles
29Si MAS NMR systematics calcic sodic-calcic amphiboles
2012/3/30
We report the compositional systematics of the 29 Si MAS NMR spectra of richterite,[A](Na,K,Rb)1(Na,Ca,Sr)2Mg5Si8O22 (OH,F)2; pargasite, NaCa2Mg4AlSi6Al2O2(OH)2; and fluor-edenite, NaCa2Mg5Si7AlO22F2....
Si-Al ordering in leucite-group minerals and ion-exchanged analogues: An MAS NMR study
Si-Al leucite-group minerals ion-exchanged analogues MAS NMR study
2012/4/6
Twoseriesofleucitegroupmaterials,withK,Rb,andCsasextra-frameworkcations,havebeensynthesizedbyionexchangefromanaturalwell-orderedanalciteandanatural29 27disorderedleucite.Siand AlMASNMRdatafortheanalci...
MAS NMR study of pentacoordinated magnesium in grandidierite
MAS NMR study pentacoordinated magnesium grandidierite
2012/4/5
The11.7T Mg, Al, Si,and BMASNMRspectraarereportedforwell-charac-terizedgrandidierite,(Mg,Fe)AlSiBO ,whichcontainsbothAlandMgin?vefoldcoor-dinationwithoxygen.TheMgspectrumisthe?rsttobereportedfor Mg,an...
Si-Al order and the I1 - I 2/c structural phase transition in synthetic CaAl2Si2O8- SrAl2Si2O8 feldspar: A 29Si MAS-NMR spectroscopic study
Si-Al order I1 - I 2/c structural phase transition synthetic CaAl2Si2O8- SrAl2Si2O8 feldspar A 29Si MAS-NMR spectroscopic study
2012/4/1
We present 29SiMAS-NMR spectroscopic data for a series of synthetic feldspar samples
along the join CaAI2Si20g-SrAI2Si20g, from which the composition dependence and cou-
pling of order parameters de...
The solubility of H2O in nominally anhydrous mantle minerals using 1H MAS NMR
H2O anhydrous mantle minerals 1H MAS NMR
2012/4/9
The dissolved H20 concentrations of experimentally produced, Fe-free, nominally an-hydrous minerals (NAMs) have been measured using, for the first time, IH magic-angle-spinning NMR spectroscopy. Atlea...
In situ 29Si MAS NMR studies of structural phase transitions of tridymite
situ 29Si MAS NMR studies phase transitions tridymite
2012/4/5
The structural phase transitions ofmonoclinic tridymite that occur at elevated temper-atures, as wellas the structure of the high-temperature modifications, have been studied by 29SiMASNMR. The sample...
The use of Monte Carlo methods to determine the distribution of Al and Si cations in framework aluminosilicates from 29Si MAS NMR data
Monte Carlo methods distribution Al and Si cations framework aluminosilicates 29Si MAS NMR data
2012/4/5
AMonteCarlo method wasdeveloped to determine the distribution ofAland Sications from 29SiMASNMR data for framework aluminosilicates. The method wasused to an-alyze data obtained from Cs-exchanged leuc...
Fe ordering in kaolinite: Insights from 29Si and 27Al MAS NMR spectroscopy
Fe ordering kaolinite Insights 29Si 27Al MAS NMR spectroscopy
2012/4/5
Kaolinite-richsamples wereselectedfor 27 Aland 29SiMASNMRstudy to explore the effectofFeontheir spectraandprovide insight into the nature ofFeorderingin kaolinite. Initial characterization bychemicala...
27Al MAS NMR and Aluminum X-ray Absorption Near Edge Structure Study of Imogolite and Allophanes
Allophane Aluminum Imogolite NMR XANES
2011/12/29
This paper compares the results of 27Al nuclear magnetic resonance spectroscopy (NMR) and Al-K-edge X-ray Absorption Near Edge Structure (XANES) of natural imogolite and allophanes and some crystallin...