搜索结果: 1-15 共查到“理学 29Si”相关记录21条 . 查询时间(0.038 秒)
本工作采用29Si CP/MS NMR和XPS测试方法对硅胶表面接枝季铵功能基团的过程和机理进行了分析。XPS光谱分析结果表明,硅基季铵化产品的XPS谱中含有Si、O、C、N元素,并出现了以R4N+形式存在的401.26 eV结合能峰,表明硅胶表面已被季铵化。TGA-DTA分析其接枝率为 0.46 mmol/g,同时,本工作采用29Si CP/MS NMR法对接枝机理进行探索研究,得出了接枝的可能...
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。
硅铝酸钠溶液中27Al和29Si的核磁共振研究
27Al核磁共振谱 29Si核磁共振谱 硅铝酸钠溶液
2009/11/23
本文采用原位核磁共振方法检测不同碱度硅铝酸钠溶液中27Al的信号, 在比较了文献实验结果的基础上, 明确了体系中的不同铝物种的化学位移, 进一步提出了硅铝酸钠溶液中的硅铝物种的归属.
摘要 原位引入有机组分对氧化硅体系改性是合成有机-无机杂化硅材料的重要方法. 利用原位的29Si液体核磁, 研究了甲醇为溶剂、氨水催化条件下的四乙氧基硅烷(TEOS)和二甲基二乙氧基硅烷(DDS)原位共水解的动力学过程. 通过改变反应体系中氨和水的浓度, 拟合出单体及中间产物浓度随时间的变化曲线, 得到了TEOS和DDS各自的水解速率常数以及相应各反应物的反应级数. 与单前驱体水解一致的是, 在双...
摘要 本文应用^29Si,^27AIMASNMR和XRD技术,测量了四种不同脱铝深度的稀土超稳Y沸石的骨架硅铝比,得到了一致的结果,并研究了稀土超稳Y沸石的脱铝过程和稀土离子和Y沸石骨架铝的机理.发现稀土离子存在时,Y沸石骨架中Si、Al的分布与相同硅铝比的HY不同,在浅、中度脱铝时,主要脱除的是Si(2Al)和Si(3Al)中的铝,深度脱铝时,主要是Si(1Al)和少量Si(2Al)中的铝,而S...
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...
A Synthetic Na-Rich Mica: Synthesis and Characterization by 27Al and 29Si Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy
KGa-1 MAS NMR Spectroscopy Metakaolinite Mica Na Mica Synthetic Clay Mineral
2011/12/7
Abstract: A swelling mica, Na2Mg3(Al2Si2)O10F2·xH2O, (hereafter “Na-4 mica”) was synthesized from metakaolinite + MgO and Mg aluminosilicate gels at different temperatures and durations using NaF flux...
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...
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 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...
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...