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Synthesis and Crystal Structure of a Cyano-bridged Bimetallic Complex K_3(TMS)_2(H_2O)_2Cr(CN)_6[TMS = Tetramethylene Sulfone]

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Chinese Journal of Structural Chemistry 2005年第4期24卷 379-382页

作者： CHENWei CHEYun-xia ZHENGJi-min DepartmentofChemistry NankaiUniversityTianjin300071China

The cyano-bridged bimetallic complex K3(TMS)2(H2O)2Cr(CN)6 with three- dimensional microporous structure was synthesized and characterized. The title complex (C14H20CrK3N, Mr = 601.78) crystallizes in monoclinic, space group C2/c with a = 14.357(4), b = 9.331(3), c = 19.180(6) ?, β = 96.754(5)o, V = 2551.6(13) ?3, Z = 4, Dc = 1.567 g/m3, μ(MoKα) = 1.141 mm-1, F(000) = 1228, the final R = 0.0440 and wR = 0.0990 for 1760 observed reflections (I > 2σ(I)). In the crystal, two [Cr(CN) ]3- units, four K+ ions and two oxygen atoms of two 6 TMS molecules are linked to form a sixteen-membered ring and an extended three-dimensional structure.

关键词： crystal structure synthesis tetramethylene sulfone cyano-bridge

Synthesis and Crystal Structure of Co(DMSO)_2(H_2O)_2(SCN)_2 with One-dimensional Hydrogen-bonded Structure (DMSO = Dimethylsulfoxide)

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Chinese Journal of Structural Chemistry 2006年第6期25卷 643-646页

作者： WEI Rong-min CHE Yun-xia ZHENG Ji-min Departmentof Biology Chemistry Tianjin Normal University Tianjin 300071 China

The title complex Co（DMSO）2（H2O）2（SCN）2 has been prepared and structurally characterized. It crystallizes in monoclinic, space group P21/n with a= 5.1981（9）, b = 11.944（2）, c = 12.646（2） A,β = 98.686（2）°, V = 776.2（2） A^3, C6H16CoN2O4S4, Mr = 367.38, Z = 2, De = 1.572 g/cm^3, F（000） = 378 and μ（MoKa） = 1.646 mm^-1. The structure was refined to R= 0.0232 and wR = 0.0645 for 1241 observed reflections with I 〉 2σ（I）. In the title complex, each Co（II） atom is octahedrally coordinated by four O atoms from two DMSO ligands and two water molecules as well as two N atoms from SCN^- ions. The title molecules are connected to each other through intermolecular hydrogen bonds to form a 1-D structure extended by eight-membered Co2O4H2 rings.

关键词： dimethylsulfoxide thiocyanate group supramolecule,complex intermolecular hydrogen bond

Synthesis and Crystal Structure of a Cyano-bridged Bimetallic Complex[La(betaine)_2(H_2O)_6Fe(CN)_6]·2H_2O

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Chinese Journal of Structural Chemistry 2005年第4期24卷 424-428页

作者： LIANGShu-Hui CHEYun-xia ZHENGJi-min DepartmentofChemistry NankaiUniversityTianjin300071China

The title complex [La(betaine)2(H2O)6Fe(CN)6]?2H2O (betaine = (CH3)3NCH2CO2) has been synthesized and characterized by X-ray single-crystal structure analysis. The crystal crystallizes in monoclinic, space group P21/n with a = 15.793(5), b = 8.927(3), c = 22.257(7) ?, β = 110.147(5)o, C16H38FeLaN8O12, Mr = 729.31, Z = 4, V = 2946.0(15) ?3, Dc = 1.640 g/m3, μ(MoKα) = 1.988 mm-1, F(000) =1476, R = 0.0388 and wR = 0.0827 for 4237 observed reflections (I > 2σ(I)). The La3+ ion is nine-coordinated by one cyano nitrogen atom and eight oxygen atoms of two betaine and six water molecules. Each complex molecule is connected to form a 3D network structure by some O–H…O and O–H…N hydrogen bonds.

关键词： crystal structure synthesis cyano-bridged bimetallic complex hydrogen bond

What decarbonized the residential building operation worldwide since the 2000s

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Petroleum Science 2022年第6期19卷 3194-3208页

作者： min-Da Ma min-xia Chen Wei Feng Jing-Wen Huo Building Technology&Urban Systems Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720United States School of Management Science and Real Estate Chongqing UniversityChongqing400045PR China Department of Earth System Science Tsinghua UniversityBeijing100084PR China

Decarbonization in operational residential buildings worldwide has become critical in achieving the carbon neutral target due to the growing household energy *** accelerate the pace of global carbon neutrality,this study explores the operational carbon change in global residential buildings through the generalized Divisia index method and decoupling analysis,considering the decarbonization levels of residential buildings at different *** results show that(1)most of the samples showed a decrease in the total emissions from 2000 to *** for China and the United States(US),the carbon emissions in global residential building operations decreased by 7.95 million tons of carbon dioxide(MtCO_(2))per year over the study *** per gross domestic product(GDP)was the most positive driver causing the decarbonization of residential buildings,while GDP was the most negative driver.(2)Carbon intensity was essential to achieving a strong decoupling of economic development and carbon *** US almost consistently presented strong decoupling,while China showed weak decoupling over the last two decades.(3)The pace of decarbonization in global residential building operations is gradually slowing *** 2000 to 2019,decarbonization from residential buildings across 30 countries was 2094.3 MtCO_(2),with a decarbonization efficiency of 3.4%.Overall,this study addresses gaps in evaluating global decarbonization from operational residential buildings and provides a reference for evaluating building decarbonization by other emitters.

关键词： Global residential building Operational decarbonization Generalized divisia index method Decoupling elasticity Building decarbonization strategies

Abnormal behavior detection by causality analysis and sparse reconstruction

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Journal of Central South University 2017年第12期24卷 2842-2852页

作者： WANG Jun xia Li-min School of Information Science and Engineering Central South University Changsha 410075 China

A new approach for abnormal behavior detection was proposed using causality analysis and sparse reconstruction. To effectively represent multiple-object behavior, low level visual features and causality features were adopted. The low level visual features, which included trajectory shape descriptor, speeded up robust features and histograms of optical flow, were used to describe properties of individual behavior, and causality features obtained by causality analysis were introduced to depict the interaction information among a set of objects. In order to cope with feature noisy and uncertainty, a method for multiple-object anomaly detection was presented via a sparse reconstruction. The abnormality of the testing sample was decided by the sparse reconstruction cost from an atomically learned dictionary. Experiment results show the effectiveness of the proposed method in comparison with other state-of-the-art methods on the public databases for abnormal behavior detection.

关键词： abnormal behavior detection Granger causality test causality feature sparse reconstruction

A regularization algorithm of dynamic light scattering for estimating the particle size distribution of dual-substance mixture in water

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Particuology 2024年第6期89卷 246-257页

作者： Yanghong Wang Ziqiang Meng Zipei Zhang min xia Li xia Wei Li School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China

Dynamic light scattering(DLS)is a nondestructive,well-established technique for the size characterization of proteins,nanoparticles,polymers,and colloidal ***,current DLS techniques are only applied to particle groups of single composition due to the limitation of their inversion *** this study,we propose a particle size distribution inversion algorithm based on the Tikhnonov regularization method that can be applied to the dual-substance particle *** algorithm retrieves the particle size distributions of two substances,respectively,by taking advantage of their refractive index *** simulation results reveal that the algorithm has excellent accuracy and stability when the scattering angle is 30°.Instead of the original identity matrix,the first-order difference matrix and second-order difference matrix are used as the regular matrix when utilizing the Tikhnonov algorithm,which obviously improves the anti-interference,accuracy,and stability of the ***,the inversion of particle size distribution is carried out at a 0.01%–1%noise level,which shows that the algorithm has an available antinoise ***,experimental particle size measurements for a mixture of polystyrene beads and toner particles demonstrate that the proposed algorithm is superior to the traditional Tikhnonov algorithm in applicability and accuracy.

关键词： Dynamic light scattering Dual-substance mixture Particle sized istribution Tikhnonov regularization

Social Capital and Socioeconomic Development in Rural China

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Fudan Journal of the Humanities and Social Sciences 2014年第4期7卷 563-581页

作者： min xia School of International Studies Renmin University of China Beijing People's Republic of China

The purpose of this article is to examine the stock of social capital in rural China and explore the different impacts of two types of social capital upon the economic development performance of rural China. This empirical study of social capital is based on an original survey of 410 villages throughout China. The findings indicate that bonding social capital still has a very solid foundation in rural areas of China. Bridging social capital is in formation in Chinese villages, even though the stock of bridging social capital is currently very moderate. Moreover, this study finds that bridging social capital, as manifested in general trust and inclusive social networks, positively affected villages＇ development performance. However, bonding social capital, as manifested in particular trust and exclusive social networks, tends to negatively impact villages＇ development performance. These findings help to shed some light on the distribution of two types of social capital-bridging and bonding-in rural China and their impact on the socioeconomic development of rural areas. Given the scarcity of representative survey studies of this sort, the findings from this study are especially valuable for establishing some conceptual and empirical baselines for subsequent studies of social capital in rural China.

关键词： Rural China Social capital Socioeconomic development

An Image Encryption Approach Using a Shuffling Map

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Communications in Theoretical Physics 2009年第11期52卷 876-880页

作者： xiaO Yong-Liang xia Li-min School of Information Science and Engineering Central South University Changsha 410083 China Department of Information Management Hunan College of Finance and Economics Changsha 410205 China

A new image encryption approach is ***,a sort transformation based on nonlinear chaoticalgorithm is used to shuffle the positions of image *** the states of hyper-chaos are used to change the greyvalues of the shuffled image according to the changed chaotic values of the same position between the above nonlinearchaotic sequence and the sorted chaotic *** experimental results demonstrate that the image encryptionscheme based on a shuffling map shows advantages of large key space and high-level *** with someencryption algorithms,the suggested encryption scheme is more secure.

关键词： image encryption hyper-chaotic shuffling sort

Hydrothermal Synthesis and Crystal Structure of a Heterometallic Cu/Cd Complex with H_2dipic(Pyridine-2,6-dicarboxylic Acid)

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Chinese Journal of Structural Chemistry 2006年第10期25卷 1250-1254页

作者： XUE Lin CHE Yun-xia ZHENG Ji-min Department of Chemistry Nankai University Tianjin 300071 China

A new heterometallic complex {[Cu（pic）2（H2O）2][Cd2（Hdipic）2（H2O）2Cl2]}n （Mr = 1007.73） has been synthesized under hydrothermal condition and characterized by single-crystal X-ray diffraction. It crystallizes in triclinic, space group PI^- with a = 5.8397（4）, b = 9.8664（7）, c = 14.1739（10） °A, α= 82.0150（10）, β = 80.4540（10）, γ= 82.3570（10）°, Z= 1, V= 792.47（10）°A^3, Dc = 2.112 g/cm^3,μ（MoKα） = 2.247 mm^-1, F（000） = 495, the final R = 0.0232 and wR = 0.0644 for 2748 observed reflections （I〉 2σ（I））. In the complex, seven-coordinated·Cd ions form a zigzag chain based on the alternated dinuclear Cd units. The neutral [Cu（pic）2（H2O）2] units are located at the centers of the inter space and fasten to the 1-D chain by hydrogen bonds.

关键词： copper cadmium heterometallic dinuclear hydrothermal coordination polymer