搜索结果: 1-15 共查到“地质学 Ordering”相关记录26条 . 查询时间(0.062 秒)
Khmaralite, a new beryllium-bearing mineral related to sapphirine: A superstructure resulting from partial ordering of Be, Al, and Si on tetrahedral sites
Khmaralite beryllium-bearing mineral related to sapphirine superstructure resulting partial ordering Be Al Si tetrahedral sites
2012/4/1
Khmaralite, Ca Mg Fe Fe Al Be B Si O , is a new mineral closely related to.04 5.46 14.26 1.43 0.02 4.80 400.12 1.87sapphirine from Khmara Bay, Enderby Land, Antarctica. It occurs in a pegmatite metamo...
Thermodynamics of cation ordering in karrooite (MgTi2O5)
MgTi2O5 Thermodynamics cation ordering karrooite
2012/4/1
A thermodynamic model of non-convergent cation-ordering in karrooite (MgTi O ) has been cali-2 5
brated from the single-crystal X-ray structure refinements of Yang and Hazen (1998) and from esti-
ma...
In situ neutron diffraction study of non-convergent cation ordering in the (Fe3O4)1-x(MgAl2O4)x spinel solid solution
non-convergent cation ordering (Fe3O4)1-x(MgAl2O4)x spinel solid solution
2012/3/31
Non-convergent cation ordering in the (Fe O ) (MgAl O ) solid solution was investigated us-
ing in-situ time-of-flight neutron powder diffraction. The approach to equilibrium in a sample with
x = 0...
Thermodynamics and kinetics of cation ordering in MgAl2O4 spinel up to 1600 °C from in situ neutron diffraction
MgAl2O4 temperature to 1600C situ neutron diffraction
2012/3/30
Thetemperaturedependenceofthecationdistributioninsyntheticspinel(MgAl O )was2 4
determinedusingin-situtime-of-?ightneutronpowderdiffraction.Neutrondiffractionpat-
ternsofstoichiometricMgAl
O andsli...
The description of Al, Si ordering in aluminosilicates using the cluster variation method
cluster variatio nmethod Al Si cluster variation method
2012/3/30
Theclustervariationmethod(CVM)fordeterminingthethermodynamicsofbothshort-
rangeandlong-rangeorderinthisstudywasextendedtocomplexaluminosilicateminerals.
Usingrecentlydevelopedalgorithmsforthemaximiz...
Comparative high-pressure crystal chemistry of karrooite, MgTi2O5, with different ordering states
high-pressure different ordering states
2012/3/30
Twokarrooitecrystals,onewithadisorderparameter(X TicontentintheM1site)
of0.070(5)andtheotherwith X 0.485(5),weremountedtogetherinonediamond-anvil
cellandstudiedbysingle-crystalX-raydiffractionatseve...
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...
Structural mechanisms of solid solution and cation ordering in augite-jadeite pyroxenes: II. A microscopic perspective
Structural mechanisms augite-jadeite pyroxenes microscopic perspective
2012/3/31
Infrared spectra of ordered (P2/n ) and disordered ( C2/c ) pyroxenes belonging to the join augite-jadeite were investigated at room temperature in the range 70–1400 cm 21. The spectra change as a fun...
Structural mechanisms of solid solution and cation ordering in augite-jadeite pyroxenes: I. A macroscopic perspective
Structural mechanisms augite-jadeite pyroxenes macroscopic perspective
2012/3/31
Single-crystal and powder X-ray diffraction data were collected to characterize the mac-roscopic solid-solution and cation-ordering behavior in the system augite-jadeite (low ac-mite content). We exam...
Cation Ordering in Synthetic Layered Double Hydroxides
Cation Ordering LDH Pyroaurite XAS XRD
2011/12/22
Abstract: A combined powder X-ray diffraction (XRD) and X-ray absorption (XAS) study of Fe(III) cation ordering within pyroaurite is described. It is concluded that there is no correlation between Fe(...
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...
Transformation of titanomagnetite to titanomaghemite; A slow, two-step oxidation-ordering process in MORB
Transformation titanomaghemite A slow two-step oxidation-ordering process MORB
2012/4/6
Theyoungestsamplehasparameterscorrespondingtonearlyunoxidizedtitanomagne-
tite,whereastheoldestisnear-end-membertitanomaghemite.Intermediatesamplesare
partiallyalteredbutdisplaynosuperstructurere?ec...
Cation ordering in lead-molybdenum-vanadium oxychlorides
Cation lead-molybdenum-vanadium oxychlorides
2012/4/9
The crystal chemistry and structure ofthe layered lead oxychloride parkinsonite, ideally Pb7Mo09C12, have been reevaluated in the light of TEM observations of natural and syn-thetic samples and the st...
Displacive phase transition in anorthoclase: The "plateau effect" and the effect of T1-T2 ordering on the transition temperature
Displacive phase transition anorthoclase plateau effect T1-T2 transition temperature
2012/4/9
The effects of compositional changes and nonsymmetry-breaking AI-Siordering onthe displacive phase transition in anorthoclase have been studied using X-ray powder diffrac-tion. The results wereanalyze...
An imaging-plate detector interfaced to a large-volume high-pressure device allows quantitative in situ powder X-ray diffraction measurements at the National Synchrotron Light Source (NSLS). High-qual...