搜索结果: 1-15 共查到“理学 MAS NMR”相关记录24条 . 查询时间(0.046 秒)
27Al和29Si MAS-NMR对Mo/HZSM-5催化剂的研究
Mo/HZSM-5 NMR 脱铝 Al2(MoO4)3 甲烷无氧活化
2009/12/14
27Al和29Si MAS-NMR对Mo/HZSM-5催化剂的研究。
利用二维多量子魔角旋转（2D MQ MAS）技术并结合量子化学计算，研究了铝在MCM-22分子筛骨架上的分布，并对铝的不等价四面体位进行了归属.在27Al 2D 5Q MAS NMR谱中骨架四配位铝的范围内观察到3个信号，证明MCM-22分子筛有3种骨架铝.经计算这3种骨架四配位铝的各向同性化学位移和四极作用常数分别为：δ 50.5、δ 57.3、δ 62.4和1.74、1.68、1.92 MHz...
有机-无机杂化磷酸锆及胺插层化合物的MAS NMR 研究
有机-无机杂化磷酸锆 胺插层化合物 MAS NMR
2008/4/30
英文关键词：zirconium phosphonate-phosphate; amine-intercalated compound; MAS NMR
The layered zirconium [N-(phosphonomethyl)iminodiacetic acid-phosphate]
Zr(HPO4)1.3...
^1^1^3Cd MAS NMR谱表征纳米CdO， CdS在NaY的β笼内 形成的构型
结构表征 纳米相材料 光敏材料 构型 分子筛 簇 硫化镉 笼状结构 氧化镉 核磁共振谱法 镉113核磁共振谱法
2007/12/19
摘要 通过29^Si,27^Al和^1^1^3CdMASNMR谱，观察到如下结果：(1)在Nayβ笼内形成的CdO和CdS簇，它们的^1^1^3Cd化学位移分别为115.0和100.0这些值接近于体相CdO的化学位移83.5，而远离体相CdS的化学位移583.8，因此它们的构型应归属为体相CdO的立方岩盐构型，而不属于体相CdS的配位数为4的闪锌矿构型。(2)CdO-NaY硫化时，NaY的骨架脱铝...
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...
LiCl/γ-Al2O3的7Li MAS NMR研究。
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...