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^(13)C nmr spectra of tectonic coals and the effects of stress on structural components

Science China Earth Sciences 2005年第9期48卷 1418-1437页

作者： JU Yiwen1,2, JIANG Bo1, HOU Quanlin2, WANG Guiliang1 & NI Shanqin2 1. College of Mineral Resource and Geosciences, China University of Mining and Technology, Xuzhou 221008, China 2. Laboratory of Computational Geodynamics, College of Geosciences, Graduate School of Chinese Academy of Sciences, Beijing 100049, China College of Mineral Resource and Geosciences China University of Mining and Technology Xuzhou China Laboratory of Computational Geodynamics College of Geosciences Graduate School of Chinese Academy of Sciences Beijing China

High-resolution 13C Nuclear Magnetic Resonance (nmr) spectra of different kinds of tectonic coals were obtained using the nmr (CP/MAS+TOSS) method. On the basis of this, after simulation synthesis and division of spectra, the relative contents of carbon functional groups were calculated. Combined with results of Ro, max, XRD testing and element analysis, stress effects on the composition of macromolecular structures in tectonic coals were studied further. The results showed that Ro, max was not only the important index for describing coal rank, but was also effective for estimating the stress effect of tectonic coals. Under tectonic stress ac- tion, Ro, max was the most direct indicator of the coal structure and chemical components. Changes in the stacking Lc of the coal basic structure unit (BSU) and La/Lc parameters could distinguish the temperature and stress effects on metamorphic-deformed environments, and re- flected the degree of structural deformation. Therefore, on the whole, Lc and La/Lc can be used to index of the degree of structural deformation of tectonic coals. In different metamorphic and de- formed environments, different kinds of tectonic coals are formed under structural stress. The changes in characteristics of the macromolecular structure and chemical composition are such that as the increase in structural deformation becomes stronger, from the brittle deformation coal to ductile deformation coal, the ratio of width at the half height of the aromatic carbon and ali- phatic carbon peaks (Hfa/Hfal ) was increased. As carbon aromaticity was raised further, carbon aliphaticity reduced obviously and different compositions of macromolecular structure appeared as a jump and wave pattern except for in wrinkle structure coal, which might result chiefly from stress effects on the macromolecular structure of different kinds of tectonic coals. The macro- moecular changes of wrinkle structure coal are reflected mainly on physical structure. In the metamorphi

关键词： tectonic coal, nmr, macromolecular structure, chemical component, stress effect.

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A new method for multi-exponential inversion of nmr relaxation measurements

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Science China(Physics,Mechanics & Astronomy) 2004年第3期47卷 265-276页

作者： WANG Zhongdong1, 2, XIAO Lizhi1 & LIU Tangyan1 1. Petroleum University, Beijing 102249, China 2. Liaohe Petroleum Administration, Panjin 124011, China Petroleum UniversityBeijingChina Liaohe Petroleum AdministrationPanjinChina

A new method for multi-exponential inversion to nmr T1 and T2 relaxation time distributions is suggested and tested. Inversion results are compared with MAP-II which is based on SVD algorithm and widely accepted in the industry. Inversed nmr relaxation spectra that have different pre-assigned relaxation times from echo trains with different SNR confirm that the new method with 16 to 64 equally spaced time constants in logarithm scale will ensure the relaxation distribution. Testing results show that the new inversion algorithm is a valuable tool for rock core nmr experimental analysis and nmr logging data process and interpretation.

关键词： nmr, inversion, relaxation, core analysis, well logging.

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One-pot Synthesis and Characterization of 13-Acetyl-9-methyl-11-oxo-8- oxa- 10,12-d iazatricyclo [7.3.1.0^2,7] trideca- 2,4,6- triene

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Chinese Journal of Chemical Physics 2006年第1期19卷 84-88页

作者： Hojatollah Salehi Qian-rong Li Qing-xiang Guo Hefei National Laboratory for Physical Sciences at Microscale Department of Chemistry University of Science and Technology of China Hefei 230026 China Scholarship Department Ministry of Science Research and Technology P.O. Box Tehran 15875-6185 Iran

为 13-acetyl-9-methyl-11-oxo-8-oxa-10,12-diazatricyclo 的一个壶合成的一个有效、环境地友好的过程[从经由由处于一个没有溶剂的条件把镁溴化物用作便宜、容易可得到的催化剂的 Biginelli 冷凝作用和 intramolecular Michael 增加的...

为 13-acetyl-9-methyl-11-oxo-8-oxa-10,12-diazatricyclo 的一个壶合成的一个有效、环境地友好的过程[从经由由处于一个没有溶剂的条件把镁溴化物用作便宜、容易可得到的催化剂的 Biginelli 冷凝作用和 intramolecular Michael 增加的 salicylaldehyde， acetylacetone 和脲的 7:3:1:0 2;7]trideca-2,4,6-triene 被描述。产品的结构的说明被 1 H-nmr 和 13 C-nmr 系列。产品能被它的 EI TOF 集体 spectrometry 也在 m/s 基于分子的离子识别 246 (10%) 并且在二个氮原子在被仍然是的碎片离子上。从分子的离子的三种典型破碎小径被观察。一个人是 OH 激进分子的损失在 m/z 形成 dihydropyrimidinone 阳离子 229 (48%) ，由在 m/z 形成 pyrimidinone 阳离子的分子的甲烷的消除列在后面 213 (27%) 。第二是 C 6 H 4 哦在 m/z 的 dihydropyrimidinone 阳离子的基，和形成 153 (24%) 。第三是 MeC=O 基的损失在 m/z 负担得起衔接氧的碎片离子 203 (33%) 。

关键词：一壶合成表征 13-乙酰基-9-甲基-11-氧-8-氧杂- 10,12-二氮杂三环[7.3.1.0^2,7]十三- 2,4,6- 三烯氧桥二氢嘧啶酮分子间迈克尔加成作用 nmr, EI-TOFMS

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Experimental and theoretical study of^(13)C shielding tensors in new-style molybdenum complex

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Science China Chemistry 2004年第3期47卷 214-221页

作者： HOU Guangjin1,2, WANG Liying2, LU Xiaoming3, ZHENG Anmin2, DENG Feng2 &YE Chaohui1,2 1. Department of Physics, Huazhong University of Science and Technology, Wuhan 430074, China 2. State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chi-nese Academy of Sciences, Wuhan 430071, China 3. Department of Chemistry, Capital Normal University, Beijing 100037, China Department of Physics Huazhong University of Science and Technology Wuhan China Chinese Academy of Sciences Wuhan China Department of Chemistry Capital Normal University Beijing China

C 2D-PASS spectra of two new cis-dioxo catecholatomolybdenum complexes (NH2CH2NH2CHCH3)2 (H+)3 [Mo(v)O2(C6H4O2)2] and (NH2CH2CH2CH2NH2)2(H+)3[Mo(v)O2(C6H4O2)2] have been obtained by solid-state nuclear magnetic resonance (nmr), in which the spinning sidebands were well-separated. The principal components of the 13C shielding tensors were ex-tracted by theoretically fitting the intensities of 13C spinning sidebands. The effects of counter cations on 13C chemical shift isotropy and shielding tensor of cis-dioxo catecholatomolybdenum complex anion [Mo(v)O2(C6H4O2)2]3- were studied, comparing the 13C CAS of those carbon sites in complex anions with that of the counter cations. Based on the dnown structure of the molyb-denum complex crystal, theoretical values of 13C shielding tensors were calculated by the ab initio GIAO method, in comparison with the experimental results.

关键词： nmr, magic angle spinning, chemical shift anisotropy, shielding tensor, cis-dioxo-monomolybdenum.

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用固体核磁共振方法研究CeO_2-γ-Al_2O_3混合氧化物中的Al状态(英文)

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波谱学杂志 2007年第1期24卷 17-25页

作者：胡伟苏永超陈雷岳勇李士杰邓风波谱与原子分子物理国家重点实验室(中国科学院武汉物理与数学研究所) 武汉430071 北京大学化学与分子工程学院北京100871

用固体核磁共振技术研究了CeO2-γ-Al2O3混合体系中CeO2和γ-Al2O3两相间的相互作用.在混合物的27Al MAS nmr中,除了四配位和六配位的Al位外,有一个尖锐的位于37处的峰,这个峰在高场处有一宽的肩峰.实验证实:位于高场的宽峰来自于γ-Al... 详细信息

用固体核磁共振技术研究了CeO2-γ-Al2O3混合体系中CeO2和γ-Al2O3两相间的相互作用.在混合物的27Al MAS nmr中,除了四配位和六配位的Al位外,有一个尖锐的位于37处的峰,这个峰在高场处有一宽的肩峰.实验证实:位于高场的宽峰来自于γ-Al2O3中的五配位Al ,而位于37处的尖峰则是由CeO2和γ-Al2O3两相间的相互作用产生的,即Al取代了CeO2晶格中八配位的Ce .定量研究表明,这种Al取代的量是极其有限的,整个CeO2晶格只有1 %的Ce能被Al取代.

关键词： ^ 27Al MAS nmr, CeO2, γ-Al2O3, substitution, MQMAS nmr

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