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Synthesis, Crystal Structure and Properties of a New Cd(II) Complex Based on Mixed 5-Hydroxy-isophthalic Acid and 1-(1H-imidazol-4-yl)-3-(4H-tetrazol-5-yl)benzene Ligands

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Chinese Journal of Structural Chemistry 2015年第6期34卷 899-905页

作者： HU Zhi-yong ZHU juan-juan CHEN Shui-Sheng QIAO Rui College of Chemistry & Chemical Engineering Fuyang Normal College

A new coordination polymer [Cd2（5-IPA）（HL）2（H20）2]＇4H20 （1） was prepared under hydrothermal conditions based on 5-hydroxy-isophthalic acid （5-H2IPA） with multi-N-donor ligand 1-（1H-imidazol-4-yl）-3-（4H-tetrazol-5-yl）benzene （H2L）. The complex was characterized by IR spectroscopy, TGA, X-ray powder and single-crystal diffraction. It crystallizes in the monoclinic system, space group C2/e with a = 23.6291（18）, b = 9.9847（8）, c = 17.7244（14） A, fl = 124.6180（10）°, V = 3441.4（5） A3, Z = 4, C28H30N12O11Cd2, Mr = 935.44, Dc = 1.805 g/cm^3,μ= 1.313 mm^-1, S = 1.055, F（000） = 1864, the final R = 0.049 and wR = 0.1315 for 2985 observed reflections （I 〉 2σ（I））. The central metal Cd（II） atoms with octahedral coordination geometry are six-coordinated by three oxygen and three nitrogen atoms. The HL- ligands from the deprotonated HzL connect Cd（II） atoms to form two-dimensional （2D） double-layer fes networks which are further pillared by 5-IPA2- ligands into a rare binodal （3, 4）-connected three-dimensional （3D） architecture with a （4·6·8）（4·62·83） fse-3,4-C2/c topology. Solid state luminescent property and sorption property of 1 have been investigated.

关键词： synthesis crystal structure luminescence property

Fuzzy entropy design for non convex fuzzy set and application to mutual information

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Journal of Central South University 2011年第1期18卷 184-189页

作者： LEE sang-Hyuk LEE sang-Min SOHN Gyo-yong KIM Jaeh-Yung Department of Electronics Engineering Inha UniversityIncheon 402-751Korea School of Electrical Engineering and Computer Science Kyungpook National UniversityDaegu 702-701Korea School of Mechatronics Changwon National University

Fuzzy entropy was designed for non convex fuzzy membership function using well known Hamming distance *** proposed fuzzy entropy had the same structure as that of convex fuzzy membership *** procedure of fuzzy entropy was proposed by considering fuzzy membership through distance measure,and the obtained results contained more flexibility than the general fuzzy membership ***,characteristic analyses for non convex function were also *** on the mutual information were carried out through the proposed fuzzy entropy and similarity measure,which was also dual structure of fuzzy *** the illustrative example,mutual information was discussed.

关键词： fuzzy entropy non convex fuzzy membership function distance measure similarity measure mutual information

Modeling Default Dependence with the Mixture of Calendar Time and Business Time

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Wuhan University Journal of Natural Sciences 2015年第2期20卷 106-112页

作者： MA yong DU juan College of Finance and Statistics Hunan University School of Economics and Management Hainan University

Evaluating default correlation between securities in a portfolio is very important for credit derivatives pricing and risk management. Under the framework of the structural model proposed by Black and Cox, we assume that the asset values of companies are driven by Brownian motions in the worlds of the calendar time and the business time; they then could evolve continuously or by leap. We build the dynamic default correlations using the time-varying correlated Brownian motions in these processes. The sensitivity of default correlations to the key parameters is explored in the paper by numerical examples, and we apply the model to risk management as well. Because default times are unpredictable in the proposed model, the defaults might occur suddenly. Independent defaults and complete correlated defaults can be described in the model as well.

关键词： default correlation business time time-changed Brownian motion Monte Carlo method

Electrochemical behavior of gold and its associated minerals in alkaline thiourea solutions

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International Journal of Minerals,Metallurgy and Materials 2018年第7期25卷 737-743页

作者： he zhou yong-sheng song wen-juan li kun song national engineering laboratory of biohydrometallurgy grimat engineering institute co.ltdbeijing 101407China school of chemical&environmental engineering china university of mining&technologybeijing 100083China

Electrochemical measurements were conducted to study the electrochemical behavior of gold （Au） and its commonly associated minerals in alkaline thiourea solutions. The results indicated that without addition of any stabilizer, selective dissolution of Au from stibnite and pyrite was only possible at relatively low thiourea concentrations. As Na2SiO3 was added, pyrite started to become active and an oxida- tion peak appeared; the oxidation peaks of axsenopyrite and chalcocite appeared earlier thaxl that of Au. The chalcocite peak shifted in the positive direction and the peak current increased. Stibnite did not show an oxidation peak and its current was nearly zero. Adding Na2SiO3 favored the selective dissolution of Au when its minerals were associated with chalcocite and stibinte. At pH 12, the Au anode dissolution peak current increased with stabilizer concentration. At 0.38 and 0.42 V and for Na2SiO3 concentration below 0.09 M, the current density continuously increased with Na2SiO3 concentration. The Na2SiO3 concentration had to be adequate to stabilize thiourea. When the potential was higher than 0.42 V, the surface of the Au electrode started to passivate. With an additional increase in potential, the presence of Na2SiO3 could not stop the inevitable decomposition of thiourea.

关键词： alkaline daiourea Au associated mineral Na2SiO3 electrochemical behavior

Observational Diagnosis of Cloud Phase in the Winter Antarctic Atmosphere for Parameterizations in Climate Models

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Advances in Atmospheric Sciences 2010年第6期27卷 1233-1245页

作者： yong-sang CHOI Chang-Hoi HO sang-Woo KIM Richard S.LINDZEN Department of Environmental Science and Engineering Ewha Womans University Department of Earth Atmospheric and Planetary SciencesMassachusetts Institute of Technology School of Earth and Environmental Sciences Seoul National University

The cloud phase composition of cold clouds in the Antarctic atmosphere is explored using data from the Moderate Resolution Imaging Spectroradiometer （MODIS） and Cloud-Aerosol Lidar with Orthogonal Polarization （CALIOP） instruments for the period 2000-2006. We used the averaged fraction of liquid-phase clouds out of the total cloud amount at the cloud tops since the value is comparable in the two measurements. MODIS data for the winter months （June, July, and August） reveal liquid cloud fraction out of the total cloud amount significantly decreases with decreasing cloud-top temperature below 0°C. In addition, the CALIOP vertical profiles show that below the ice clouds, low-lying liquid clouds are distributed over ～20% of the area. With increasing latitude, the liquid cloud fraction decreases as a function of the local temperature. The MODIS-observed relation between the cloud-top liquid fraction and cloud-top temperature is then applied to evaluate the cloud phase parameterization in climate models, in which condensed cloud water is repartitioned between liquid water and ice on the basis of the grid point temperature. It is found that models assuming overly high cut-offs （ -40°C） for the separation of ice clouds from mixed-phase clouds may significantly underestimate the liquid cloud fraction in the winter Antarctic atmosphere. Correction of the bias in the liquid cloud fraction would serve to reduce the large uncertainty in cloud radiative effects.

关键词： cloud phase mixed-phase clouds polar cloud cloud radiative effect cloud parameterization

Controllable Spin Polarization of Charge Current by Rashba Spin Orbital Coupling

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Communications in Theoretical Physics 2009年第11期52卷 949-952页

作者： CUI juan YANG yong-Hong WANG Jun Department of Physics Southeast University Nanjing 210096 China Department of Physics Yancheng Techers University Yancheng 224002 China

We report a theoretic study on modulating the spin polarization of charge current in a mesoscopic fourterminal device of cross structure by using the inverse spin hall effect. The scattering region of device is a two-dimensional electron gas （2DEG） with Rashba spin orbital interaction （RSOI）, one of lead is ferromagnetic metal and other three leads are spin-degenerate normal metals. By using Landauer-Biittiker formalism, we found that when a longitudinal charge current flows through 2DEG scattering region from FM lead by external bias, the transverse current can be either a pure spin current or full-polarized charge current due to the combined effect of spin hall effect and its inverse process, and the polarization of this transverse current can be easily controlled by several device parameters such as the Fermi energy, ferromagnetic magnetization, and the RSOI constant. Our method may pave a new way to control the spin polarization of a charge current.

关键词： spin polarization spin-orbital coupling spin-Hall effect Green's function

Microscopic Determination of Leading Terms of the Interaction Hamiltonian Between sd- and g-Parts in the sdg IBM

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Chinese journal of nuclear physics 1995年第4期17卷 318-321页

作者： Zhang, Zhanjun Liu, yong sang, Jianping Huazhong Normal Univ Wuhan China

Starting from one of the microscopic sdg interacting boson approximations, the lead-ing terms in the interaction Hamiltonian are discussed by using numerical investigations. Com-parisons of both the calculated levels and the overlap of wave functions between the exact re-sults and the approximations are made to find out negligible part in the Hamiltonian. The re-sults show that the leading terms given in this paper may provide a way to simplify the complexcalculations.

关键词： The sdg interacting boson model Determination of leading terms Microscopic investigation

0.22 THz Waveguide Bandpass Filter with High Stop-Band Suppression

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Journal of Electronic Science and Technology 2017年第3期15卷 263-266页

作者： Meng-juan Zhao yong Zhang Shuang Liu Fundamental Science on Extremely High Frequency (EHF) Laboratory University of Electronic Science and Technology of China Chengdu 611731

A terahertz（THz） waveguide band-pass filter using an iris inductive window coupled structure was designed and *** filter was designed at0.22 THz with a pass band of 20 *** measured results show that the center frequency is 0.218 THz with a pass band of 0.205 THz to 0.231 THz,the minimum insertion loss is 1.26 d B at 0.224 THz,and the return loss is less than 13.1 d *** stop-band suppression is65.6 d B at 0.193 THz and 51.8 d B at 0.243 THz,respectively,which means a good performance of high stop-band suppression.A good agreement exists between the measured S-parameters and the simulated ones,especially in the upper *** proposed THz waveguide filter has potential applications in THz communications.

关键词： Index Terms--High stop-band suppression,terahertz waveguide band-pass filter

Dynamic covalent gels assembled from small molecules：from discrete gelators to dynamic covalent polymers

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Chinese Chemical Letters 2017年第2期28卷 168-183页

作者： Jian-yong Zhang Li-Hua Zeng juan Feng Sun Yat-Sen University Lehn Institute of Functional Materials MOE Key Laboratory of Polymeric Composite and Functional MaterialsGuangzhou 510275 China

Dynamic covalent chemistry has emerged recently to be a powerful tool to construct functional *** article reviews the progress in the research and development of dynamic covalent chemistry in gels assembled from small *** dynamic covalent reactions used in gels are reviewed to understand the dynamic covalent *** the catalogues of dynamic covalent gels are reviewed according to the nature of gelators and the interactions between *** covalent bonding can be involved to form low molecular weight *** molecular weight molecules with multiple functional groups react to form dynamic covalent cross-linked polymers and act as *** catalogues of gels show different properties arising from their different *** review aims to illustrate the structure-property relationships of these dynamic covalent gels.

关键词： Gels Dynamic covalent chemistry Supramolecular gels Molecular gels Porous materials