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Solid State Photochemistry of Nitrobenzaldehydes

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Chemical Research in Chinese Universities 1995年第2期11卷 111-116页

作者： DU Da-nung,WANG Yong-mei,XIONG Guo-xiangWANG Wen-guang and meng ji-ben (Department of Chemistry,Nankai University,Tianjin,300071) NANKAI UNIV DEPT CHEMTIANJIN 300071PEOPLES R CHINA

The photochemical reaction of nilrobenzaldehyde with indole and antipyrine was investigated in solid *** structures of the new products were identified by means of IR,MS,'H NMR and elemental analysis,and the crystal structure of audition product 2c was determined by X-ray diffraction *** mechanism of this reaction was also proposed.

关键词： Nitrobenzaldellyde Indole Aniipyrine Solid state Photochemical reaction

5,5′-二甲基-2,2′-二茚满-1,1′,3,3′-四酮的合成及结构表征

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高等学校化学学报 2010年第6期31卷 1072-1074页

作者：李平孟继本天津理工大学化学化工学院天津300384 南开大学化学系天津300071

Based on the synthesis of 2,2′-bisindan-1,1′,3,3′-tetrone(1),5,5′-dimethyl-2,2′-bisindan-1,1′,3,3′-tetrone(2) was *** paper described the synthetic process and confirmed the characteristic of compound 2 by elemental analysis,1H NMR,FTIR and MS,then discussed a possible existing *** 2 maily existed as en-ol form and had H-bonds in the *** the same time,the ESR value of compound 2 was given as g=2.0042,could form stable radical.

关键词： 4-甲基苯二甲酸酐异构化氢键

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连茚四酮类有机磁性化合物的合成及性能

高等学校化学学报 2010年第9期31卷 1786-1790页

作者：李平孟继本天津理工大学化学化工学院天津300384 南开大学化学系天津300071

分别以邻苯二甲酸酐、4-甲基邻苯二甲酸酐和四氯邻苯二甲酸酐为原料,采用Gabriel&Leupold法合成了3个连茚四酮类化合物,即2,2'-二茚满-1,1',3,3'-四酮(1)、5,5'-二甲基-2,2'-二茚满-1,1',3,3'-四酮(2)和4,4',5,5',6,6',7,7'-八氯-2,2'-二茚满-1,1',3,3'-四酮(3).元素分析、1HNMR、FTIR和MS测定分析表明,此3个分子主要以烯醇式存在,同时存在分子内氢键;通过电子自旋共振(ESR)谱测定,给出了各化合物的ESR谱参数值.结果表明,化合物1～3均有良好的ESR图谱,是只含有C,H,O及Cl的纯有机磁性化合物,分子内都含有稳定的自由基.通过量子化学计算,推测出了自由基可能形成的位置及此类化合物最可能的存在形式(烯醇式),且证明分子内存在1个氢键.

关键词：连茚四酮异构化氢键电子自旋共振波谱量子化学计算

A Tri-mode of Mock-Walker Cells

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Advances in Atmospheric Sciences 2024年第4期41卷 671-679页

作者： Han QIN ji NIE Zhiyong meng Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100871China China Meteorological Administration Tornado Key Laboratory Foshan 528061China

This work uses cloud-resolving simulations to study mock-Walker cells driven by a specified sea surface temperature(SST).The associated precipitation in the mock-Walker cells exhibits three different modes,including a single peak of precipitation over the SST maximum(mode 1),symmetric double peaks of precipitation straddling the SST maximum(mode 2),and a single peak of precipitation on one side of the SST maximum(mode 3).The three modes are caused by three distinct convective activity center migration *** indicate that the virtual effect of water vapor plays an important role in differentiating the three *** the SST gradient is large,the virtual effect may be strong enough to overcome the temperature effect,generating a low-level low-pressure anomaly below the ascending branch of the Walker cell off the *** results here highlight the importance of the virtual effect of water vapor and its interaction with convection and large-scale circulation in the Walker circulation.

关键词： Walker circulation cloud-resolving simulation virtual effect

Compound Product of Hypermatrices

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Journal of Systems Science & Complexity 2024年第1期37卷 169-183页

作者： CHENG Daizhan meng Min ZHANG Xiao ji Zhengping Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China Department of Control Science and Engineering School of Electronics and Information EngineeringTongji UniversityShanghai 201210China National Center for Mathematics and Interdisciplinary Sciences Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100149China.

The semi-tensor product(STP)of matrices is generalized to multidimensional arrays,called the compound product of *** product is first defined for three-dimensional hypermatrices with compatible orders and then extended to general *** different types of hyperdeterminants are introduced and certain properties are *** Lie groups and Lie algebras corresponding to the hypermatrix products are ***,these results are applied to dynamical systems.

关键词： Compound semi-tensor product hyperdeterminants hypereigenvalues and hypereigenvectors hypergeneral linear groups hypermatrices.

Restricted Arc-Connectivity of Harary Digraphs

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Journal of the Operations Research Society of China 2024年第2期12卷 540-547页

作者： Jun-Hao Zhang ji-Xiang meng College of Mathematics and System Science Xinjiang UniversityUrumqi 830046XinJiangChina

The h-restricted arc-connectivity of a digraph is an important parameter to measure fault-tolerance of interconnection *** paper determines that the h-restricted arc-connectivity of the Harary digraph D=G(n;1,2,.:,k)i... 详细信息

关键词： Restricted arc-connectivity λ_(h)(D) Super-λ_(h) λ_(h)-Atom λ_(h)-Superatom

Synthesis　and　Crystal　Structure　of　3，3－Diphenylnaphtho　［1，2－b］furan－2（3H）－one

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Chinese Journal of Structural Chemistry 1994年第2期13卷 99-101页

作者： meng ji-ben Wen Zhong Wang Yong-Mei Wang Ru-ji Wang Hong-Gen (Department of Chemistry and Central Laboratory,Nankai Universily.Tianjin,300071)

In the absence of organic *** Lewis-acid catalyzed condensation reaction between benzil and α-naphthol gives 3,3-diphenylnaphtho[1, 2-b]furan-2 (3H)-one(DPNF).Its crystallographic data are as follows:C_(24)H_(16)O_2 M_r=336.39,triclinic,space group P1,a=8.394(2).b=10.292(5),c=11.175(6) α=107. 83(4).β=98.18(4),γ=100. 94 (3)°;V=881.3(6),Z=2,D_x=1.27 g/cm￣3,μ=0.74 cm￣(-1),F(000)=352,R=0.060,Rω=*** lactone ring is found to be the same plane with naphtho ring.

关键词： synthesis crystal structure condensation reaction diphenylnaphtho furan

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三种天然脱氧核苷的高效合成

高等学校化学学报 2006年第4期27卷 666-668页

作者：季奇黄飞李金亮孟继本南开大学化学系天津300071 上海迪塞诺生物医药有限公司上海201203

Three natural deoxynucleosides were synthesized with a high stereoselectivity and good or excellent *** the preparation of 2′-deoxy-β-D-adenosine, glycosidations between 1-chloro-2-deoxy-3,5-di-O-(p-chlorobenzyl)-α-D-erythro-pentofuranose and silylated adenine as well as adenine sodium salt were systematically studied.A simple synthesis route to prepare 2′-deoxy-β-D-adenosine without chromatography was developed,making 2-deoxy-β-D-adenosine readily accessible in an industrial *** efficient synthesis of 2′-deoxy-β-D-cytidine and 2′-deoxyβ-D-thymidine were also achieved without chromatography by glycosidations between 1-chloro-2-deoxy-3,5-di-O-(p-chlorobenzyl)-α-D-erythro-pentofuranose and silylated bases via the similar procedure.

关键词：核苷合成立体选择性

Fuzzy-Model-Based Finite Frequency Fault Detection Filtering Design for Two-Dimensional Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第10期11卷 2099-2110页

作者： meng Wang Huaicheng Yan jianbin Qiu Wenqiang ji Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationSchool of Information Science and EngineeringEast China University of Science and TechnologyShanghai 200237China Research Institute of Intelligent Control and Systems School of AstronauticsHarbin Institute of TechnologyHarbin 150080China School of Artificial Intelligence Hebei University of TechnologyTianjin 300401China IEEE

This article studies the fault detection filtering design problem for Roesser type two-dimensional(2-D)nonlinear systems described by uncertain 2-D Takagi-Sugeno(T-S)fuzzy ***,fuzzy Lyapunov functions are constructed and the 2-D Fourier transform is exploited,based on which a finite frequency fault detection filtering design method is proposed such that a residual signal is generated with robustness to external disturbances and sensitivity to *** has been shown that the utilization of available frequency spectrum information of faults and disturbances makes the proposed filtering design method more general and less conservative compared with a conventional nonfrequency based filtering design ***,with the proposed evaluation function and its threshold,a novel mixed finite frequency H_(∞)/H_(-)fault detection algorithm is developed,based on which the fault can be immediately detected once the evaluation function exceeds the ***,it is verified with simulation studies that the proposed method is effective and less conservative than conventional non-frequency and/or common Lyapunov function based filtering design methods.

关键词： Fault diagnosis finite frequency specifications mixed H_(∞)/H_(-)performance two-dimensional nonlinear systems