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Chinese Science Bulletin 1989年第13期34卷 1100-1105页

作者：高忠理刘有成 Department of Chemistry Lanzhou University

Studies on the mechanism of the reactions involving coenzyme NAD(P)H and its model compounds are of considerable significance for understanding the role and the mechanism of this coenzyme in living cells. Although the... 详细信息

关键词： 1-benzyl-1 4-dihydronicotinamide radical cation

Photochemistry of phenothiazine in benzene and cyclohexane

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Chinese Science Bulletin 1997年第12期42卷 998-1000页

作者： Wang, SH Chen, DW Gou, JX Wang, H Institute of Chemistry Chinese Academy of Sciences Beijing China

IN the last few years phenothiazine(PTH)and its derivatives have captured much attention inthe fields of medicines,biology,and microelectronic materials due to their ability to ef-ficiently photosensitize acid production in the presence of vicinal dibromides and hence tochange the solubilization of polymer films.The photophysical and photochemical properties re-lated to the processes have been studied.Monica Barra et al.found that the triplet

关键词： photochemistry ESR nitroxyl radical cation radical.

Studies of the Oxidation of Hexabenzylhexaazaisowurtzitane

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Journal of Beijing Institute of Technology 2010年第4期19卷 476-479页

作者：李亚裕王琳林秋汉马巧丽庞思平于永忠 School of Materials Science and Engineering Beijing Institute of Technology Beijing Institute of Aerospace Testing Technology China Ordnange Industrial Standardization Research Institute

A series of oxidation reactions of hexabenzylhexaazaisowurtzitane（HBIW,1） were studied.Compound 1 was treated with potassium permanganate in CH2Cl2 by adding Na2CO3 to adjust pH to 7-8 to obtain tetrabenzoyldibenzylhexaazaisowurtzitane（3） with a yield of 70%.With acetic anhydride（Ac2O） as solvent,monoacetyltribenzoyldibenzylhexaazaisowurtzitane（4）,diacetyldibenzoyldibenzylhexaazaisowurtzitane（5）,triacetylmonobenzoyldibenzylhexaazaisowurtzitane（6） and tetraacetyldibenzylhexaazaisowurtzitane（7） were also obtained from the oxidation of compound 1.The results show that only the oxidative cleavage of the cage system in compound 1 was observed in most cases.The cleavage was a cation catalysis mechanism.

关键词： Hexabenzylhexaazaisowurtzitane oxidation cleavage cage system cation

Sea water intrusion and salt water intrusion in the coastal area of Laizhou Bay

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Chinese Science Bulletin 1998年第12期43卷 983-992页

作者： Xue Yuqun Wu Jichun Xie Chunhong Zhang Yongxiang Nanjing Univ Dept Earth Sci Nanjing 210093 Peoples R China Nanjing Univ Dept Math Nanjing 210093 Peoples R China

The characteristics, pattern, hydrodynamic and hydrochemical features, and the movement pattern of the salt water-fresh water interface of the sea water intrusion and the salt water intrusion, which occur in the coastal area of Laizhou Bay in Shandong Province, are analysed. The characteristics of the two kinds of intrusion are compared as well. A three-dimensional sea water intrusion model to describe the sea water intrusion with a transitional zone 1.56.0 km wide in the phreatic aquifer and a solute transport model describing the behavior of cations exchange in the process of sea water intrusion are established.

关键词： sea water intrusion salt water intrusion cation exchange salt water-fresh water interface numerical simulation.

离子液体插层导致的MoTe2,WTe2拓扑及超导性质的双重调控

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Science Bulletin 2020年第3期65卷 188-193页

作者：张浩雄阿瓦拜克力·肉苏里沈胜春张柯楠王冲罗来鹏王吉章吴扬徐勇段文晖姚宏于浦周树云 State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics Tsinghua UniversityBeijing 100084China Department of Mechanical Engineering and Tsinghua-Foxconn Nanotechnology Research Center Tsinghua UniversityBeijing 100084China Frontier Science Center for Quantum Information Beijing 100084China Institute for Advanced Study Tsinghua UniversityBeijing 100084China

使拓扑材料具有超导电性是实现拓扑超导的一个重要途径.Td相的MoTe2和WTe2不仅具有新颖的拓扑性质,其物理特性紧密依赖于层间耦合作用的强弱.本工作通过一种新颖的实验方法,在MoTe2和WTe2单晶样品中插入离子液体的有机阳离子,制备出层... 详细信息

使拓扑材料具有超导电性是实现拓扑超导的一个重要途径.Td相的MoTe2和WTe2不仅具有新颖的拓扑性质,其物理特性紧密依赖于层间耦合作用的强弱.本工作通过一种新颖的实验方法,在MoTe2和WTe2单晶样品中插入离子液体的有机阳离子,制备出层间距可调、性质稳定且超导增强的有机-无机复合样品.插层后的MoTe2样品属于三维弱拓扑绝缘体,超导转变温度从0.25 K大幅提高到了7 K;而插层后WTe2的超导转变温度提高到了具有量子自旋霍尔效应的单层WTe2的2.8倍(2.3 K).本工作通过插层离子液体的有机阳离子到MoTe2和WTe2样品中,实现对其拓扑及超导性质的双层调控,为后续研究拓扑超导、实现马约拉纳零模提供了新的机遇.另外,这一新方法具有普适性,可以广泛适用于各种层状材料,这将为在层状材料中探索和实现更多新颖物理性质提供便利.

关键词： Intercalation of organic cation Topological materials Weyl semimetals MoTe2 and WTe2 Ionic liquids cations Organic-inorganic hybrid materials Enhanced superconductivity

Effects of Layer Change and Chemical Composition on Thermal Stability and Catalytic Activity of Pillared Montmorillonite

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石油学报（石油加工） 1997年第S1期13卷 97-101页

作者： Liao Huisheng , He Mingyuan (Research Institute of Petroleum Processing, Beijing 100083)

ＥｆｅｃｔｓｏｆＬａｙｅｒＣｈａｎｇｅａｎｄＣｈｅｍｉｃａｌＣｏｍｐｏｓｉｔｉｏｎｏｎＴｈｅｒｍａｌＳｔａｂｉｌｉｔｙａｎｄＣａｔａｌｙｔｉｃＡｃｔｉｖｉｔｙｏｆＰｉｌａｒｅｄＭｏｎｔｍｏｒｉｌｏｎｉｔｅＬｉａｏＨｕ... 详细信息

ＥｆｅｃｔｓｏｆＬａｙｅｒＣｈａｎｇｅａｎｄＣｈｅｍｉｃａｌＣｏｍｐｏｓｉｔｉｏｎｏｎＴｈｅｒｍａｌＳｔａｂｉｌｉｔｙａｎｄＣａｔａｌｙｔｉｃＡｃｔｉｖｉｔｙｏｆＰｉｌａｒｅｄＭｏｎｔｍｏｒｉｌｏｎｉｔｅＬｉａｏＨｕｉｓｈｅｎｇ，ＨｅＭｉｎｇｙｕａｎ...

关键词： pillared montmorillonite layer structure cation exchange capacity thermal stability catalytic property hydrocracking reaction

Hydrothermal Chemistry Involved in Developing Practical Y Type Zeolite Catalysts

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石油学报（石油加工） 1997年第S1期13卷 92-96页

作者： He Mingyuan, Shu Xingtian, Min Enze (Research Institute of Petroleum Processing, Beijing 100083)

ＨｙｄｒｏｔｈｅｒｍａｌＣｈｅｍｉｓｔｒｙＩｎｖｏｌｖｅｄｉｎＤｅｖｅｌｏｐｉｎｇＰｒａｃｔｉｃａｌＹＴｙｐｅＺｅｏｌｉｔｅＣａｔａｌｙｓｔｓＨｅＭｉｎｇｙｕａｎ，ＳｈｕＸｉｎｇｔｉａｎ，ＭｉｎＥｎｚｅ（Ｒｅｓｅａｒ... 详细信息

ＨｙｄｒｏｔｈｅｒｍａｌＣｈｅｍｉｓｔｒｙＩｎｖｏｌｖｅｄｉｎＤｅｖｅｌｏｐｉｎｇＰｒａｃｔｉｃａｌＹＴｙｐｅＺｅｏｌｉｔｅＣａｔａｌｙｓｔｓＨｅＭｉｎｇｙｕａｎ，ＳｈｕＸｉｎｇｔｉａｎ，ＭｉｎＥｎｚｅ（ＲｅｓｅａｒｃｈＩｎｓｔｉｔｕｔｅｏｆＰｅｔｒ...

关键词： Y zeolite hydrothermal chemistry rare earth cation dealumination silicon insertion

Novel SPECT Technologies and Approaches in Cardiac Imaging

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Cardiovascular Innovations and Applications 2016年第B12期2卷 31-46页

作者： Piotr Slomka Guang-Uei Hung Guido Germano Daniel S.Berman Departments of Imaging and Medicine Cedars-Sinai Medical CenterLos AngelesCAUSA Department of Nuclear Medicine Chang Bing Show Chwan Memorial HospitalChanghuaTaiwan

Recent novel approaches in myocardial perfusion single photon emission CT(SPECT)have been facilitated by new dedicated high-effi ciency hardware with solid-state detectors and optimized collimators.New protocols include very low-dose(1 mSv)stress-only,two-position imaging to mitigate attenuation artifacts,and simultaneous dual-isotope imaging.Attenuation correction can be performed by specialized low-dose systems or by previously obtained CT coronary calcium scans.Hybrid protocols using CT angiography have been proposed.Image quality improvements have been demonstrated by novel reconstructions and motion correction.Fast SPECT acquisition facilitates dynamic fl ow and early function measurements.Image processing algorithms have become automated with virtually unsupervised extraction of quantitative imaging variables.This automation facilitates integration with clinical variables derived by machine learning to predict patient outcome or diagnosis.In this review,we describe new imaging protocols made possible by the new hardware developments.We also discuss several novel software approaches for the quantifi cation and interpretation of myocardial perfusion SPECT scans.

关键词： myocardial perfusion imaging single photon emission computed tomography fast myocardial perfusion single photon emission computed tomography quantifi cation low dose stress only

Recent development in NMDA receptors

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维普期刊数据库

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Chinese Medical Journal 2000年第10期113卷 84-92页

作者：刘云张均田 National Institute of Mental Health Department of Pharmacology Institute of Materia MedicaChinese Academe of Medical Sciences

Purpose To identify the structure and the function of NMDA receptors, to understand the modulatory mechanism of some endogenous and exogenous compounds on NMDA receptors, and to provide theoretical basis for developing new drugs that modulate NMDA receptors Data sources A total of 24 originally identified articles were selected Study selection A total of 24 articles were selected from several hundred original articles or reviews. The content of selected articles are in accordance with our purpose and the authors are authorized scientists in the study on NMDA receptors.Data extraction After careful review of the selected papers, the meaningful results and conclusions were extracted using scientific criteria and our experience in the research of NMDA receptors.Results NMDA receptor contains at least five subunits. They were designated as the NR1 (ζ1), NR2A (ε1), NR2B (ε2), NR2C (ε3), and NR2D (ε4). A unique feature of NMDA receptor is the requirement for both glutamate and the co agnist glycine for the efficient gating. NMDA receptor is modulated by a number of endogenous and exogenous compounds. Mg 2+ not only blocks the NMDA channel in a voltage dependent manner but also potentiates NMDA induced responses at positive membrane potentials. Na +, K + and Ca 2+ not only pass through the NMDA receptor channel but also modulate the activity of NMDA receptors. Zn 2+ blocks the NMDA current in a noncompetitive and a voltage independent manner. It has been demonstrated that polyamines do not directly activate NMDA receptors, but instead act to potentiate or inhibit glutamate mediated responses. The activity of NMDA receptors is also strikingly sensitive to the changes in H + concentration, and partially inhibited by the ambient concentration of H + under physiological conditions.Conclusions NMDA receptors are glutamate regulated by ion channels that are permeable to Ca 2+ , Na +, K + and are sensitive to voltage dependent Mg 2+ block This channel complex contributes to excit

关键词： NMDA receptor ion-channel cation amino acid

A Study on the Underlying Mechanism of the Emergence of Gated Communities in Urban China

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China City Planning Review 2016年第4期25卷 20-25页

作者： Yang Hongping Qian Fang Jiangsu Institute of Urban Planning and Design(former) NanjingP.R.China 不详

Modern gated communities have emerged in China against a background of socio-economic transition. They are different from the gated communities in western countries in many aspects. In particular, they bear obvious Chinese characteristics in the reasons for their popularity. In order to explore the underlying economic, social, political, and cultural mechanism of the popularity of gated communities in China, this article conducts a comprehensive analysis from many angles by drawing on various theories. It is concluded that the emergence of gated communities in urban China is pushed by the special social relations of production in the period of transition. In particular the social, economic, governmental, and individual powers together promote the emergence and development of gated communities.

关键词： gated communities social stratifi cation driving mechanism