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Journal of Materials Science & Technology 2022年第21期116卷 41-49页

作者： Guocheng Huang Guiyun Lin qing Niu Jinhong bi Ling Wu Department of Environmental Science and Engineering Fuzhou UniversityMinhouFujian 350108China State Key Laboratory of Photocatalysis on Energy and Environment Fuzhou UniversityMinhouFujian 350108China

Single-atom catalysts(SACs)have emerged as an advanced frontier in heterogeneous catalysis due to their potential to maximize the atomic ***,covalent triazine-based frameworks(CTFs)confining cobalt single atoms(Co-SA/CTF)photocatalysts have been synthesized and used for efficient CO_(2) reduction and hydrogen production under visible light *** resulted Co-SA/CTF demonstrate excellent photocatalytic activity,with the CO and H2 evolution rates reaching 1665.74μmol g^(−1) h^(−1) and 1293.18μmol g^(−1) h^(−1),respectively,far surpassing those of Co nanoparticles anchored CTF and pure CTF.A variety of instrumental analyses collectively indicated that Co single atoms sites served as the reaction center for activating the adsorbed CO_(2) molecules,which significantly improved the CO_(2) reduction ***,the introduction of Co single atoms could accelerate the separation/transfer of photogenerated charge carriers,thus boosting the photocatalytic *** study envisions a novel strategy for designing efficient photocatalysts for energy conversion and showcases the application of CTFs as attractive support for confining metal single atoms.

关键词： Covalent triazine-based frameworks Co single atoms Photocatalysis CO_(2)reduction Hydrogen evolution

Effect of Ce addition on microstructures and mechanical properties of A380 aluminum alloy prepared by squeeze-casting

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International Journal of Minerals,Metallurgy and Materials 2018年第5期25卷 554-563页

作者： Xiao-hui Ao Shu-ming Xing Bai-shui Yu qing-you Han School of Mechanical Electronic and Control Engineering Beijing Jiaotong University Department of Mechanical Engineering Technology Purdue University

The effect of cerium(Ce)addition on the eutectic Si,β-Al_5Fe Si phase,and the tensile properties of A380 alloy specimens prepared by squeeze-casting were studied by optical microscopy(OM),scanning electron microscopy(SEM),and X-ray diffraction(XRD).The experimental results showed that Ce more effectively modified the eutectic Si and refined theβ-Al_5Fe *** refinement effect significantly increased under a specific pressure of 100 MPa with the addition of Ce from 0.1wt%to 0.9wt%.In contrast,the average length and the aspect ratio of the eutectic Si andβ-Al_5Fe Si exhibited their optimal values when the content of the added Ce was greater than 0.5wt%.Needle-like Al_8Cu_4Ce was precipitated with the addition of excessive Ce;hence,the mechanical properties of A380 gradually decreased with increasing Ce content in the range from 0.3wt%to 0.9wt%.

关键词： cerium eutectic Si Fe-rich phases squeeze-casting mechanical properties

Effects of tachyplesin on proliferation and differentiation of human hepatocellular carcinoma SMMC-7721 cells

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World Journal of Gastroenterology 2002年第6期8卷 1053-1058页

作者： Gao-LiangOuyang Qi-FuLi Xuan-XianPeng qing-RongLiu shui-GenHon LaboratoryofCellbiology SchoolofLifeSciertcesXiamenUniverstiyXiamen361005FujinProvinceChina TheKeyLaboratoryofChinaEducationMinistryforCellbiologyandTumorCellEngincering SchooloflifeSciencesXiame

AIM: To investigate the antitumor activities of tachyplesin on human hepatocellula r carcinoma (HCC) ***: Tachyplesin, isolated from acid extracts of Chinese horseshoe crab (Tachypleus tridentatus) hemocytes, was used to treat the human HCC cell line SMMC-7721. Effects of tachyplesin on the proliferation of SMMC-7721 cells were measured with trypan blue dye exclusion test and HE staining. The morphology and ultrastructure of the cells were examined by light microscopy and transmission electron microscopy, respectively. The activities of γ-glutamyltransferase (γ-GT) and tyrosine aminotransferase (TAT) were assayed with biochemical methods. The levels of alpha fetoprotein (α-FP), proliferating cell nuclear antigen (PCNA), p21wAF1/CIP1 and c-myc were examined by immunocytochemistry. RESULTS: After treatment with tachyplesin 3.0 mg/L, the proliferation of SMMC-7721 cells was inhibited significantly, with the cell growth inhibitory rate amounted to 55.57 % and the maximum cell mitotic index declined by 43.68 %. The morphology and ultrastructure underwent restorational alteration. The activity of γ-GT declined while TAT activity increased obviously, and the levels of α-FP and PCNA decreased. Moreover, the expression of p21WAF1/CIP1 protein was upregulated and that of c-myc protein was down-regulated. CONCLUSION: Tachyplesin could effectively inhibit the proliferation of hepatocarcinoma cells, reverse the malignant morphological and ultrastructural characteristics, alter the levels of enzymes and antigens, regulate the expression of differentiation-associated oncogene and tumor suppressor gene, and induce hepatocarcinama cell differentiation.

关键词：肝细胞癌 SMMC-7721细胞系鲎海洋生物活性物质 Tachyplesin 细胞增殖细胞分化

Attack Simulation Model and Channel Statistics in Underwater Acoustic Sensor Networks

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Tsinghua Science and Technology 2011年第6期16卷 611-621页

作者： Nan Jing Weihong bi qing Yue College of Information Science and Engineering Yanshan University Qinhuangdao 066004 China Qinhuangdao City Public Security Bureaus Qinhuangdao 066000 China

In recent years, underwater acoustic wireless sensor networks have been used in many areas. There have been many field trials of acoustic propagation models and statistics for shallow water conditions. However, field trials are limited environmentally and, hence, not widely accepted. Simulations of the impulse response of a shallow underwater acoustic channel allows less expensive system tests that are reproducable. This paper presents a shallow water acoustic channel model based on the actual acoustic propagation characteristics with path attenuation, ambient noise, multiple paths, and Doppler effects. The second-order statistical characteristics of the simulation model are verified with the autocorrelations and crosscorrelations of the quadrature components and the complex envelopes of channel impulse responses. The channel model is implemented in Matlab with the results showing that the absorption coefficient and path losses are both dependent on the frequencies and propagation distances and that the path gain can be improved with Light of Sight （LOS） and short range acoustic propagation. Analysis of the channel impulse response and the frequency response that the zero-order Bessel function of first kind can be used to describe the correlation functions for the impulse response. The shallow underwater acoustic channel is time-varying and can not be modeled as a wide-sense stationary-uncorrelated scattering channel.

关键词： simulation model absorption coefficient path loss Doppler statistical characteristics

High Strength and Stable Proton Exchange Membrane Based on Perfluorosulfonic Acid/Polybenzimidazole

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Chinese Journal of Polymer Science 2022年第7期40卷 764-771页

作者： Tang-Cheng Xu Chang-shui Wang Zhao-Yu Hu Jiao-Jiao Zheng Shao-Hua Jiang shui-Jian He Hao-qing Hou College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang330022China Co-Innovation Center of Efficient Processing and Utilization of Forest Resources College of Materials Science and EngineeringNanjing Forestry UniversityNanjing210037China

In this work,a series of high strength,thermal stable and antioxidant proton exchange membranes were designed with solution processible polybenzimidazole(Pbi)as the matrix and perfluorosulfonic acid(PFSA)as the fortifier for proton *** processible Pbi was successfully synthesized by introducing 4,4’-dicarboxydiphenyl ether into the molecular chains of ***/Pbi composite membranes were obtained by solution blending and film *** and PFSA/Pbi composite membranes exhibited greatly enhanced tensile strength and Young’s modulus compared to ***/Pbi composite membranes are stable below 300℃ which are suitable for practical application in proton exchange membrane fuel *** PFSA/Pbi composite membranes show good dimensional stability with low water uptake and swelling *** PFSA/Pbi composite membranes also exhibit excellent antioxidation stability with less than 5%initial mass loss over 120 h in Fenton *** proton conductivity of Pbi is greatly enhanced by blending with PFSA and the proton conductivities of the composite membranes are increased with the raise of PFSA content and *** work offers valuable insights into the exploration of Pbi based high-performance proton exchange membranes.

关键词： Solution processible polybenzimidazole Perfluorosulfonic acid Proton exchange membrane Film casting High strength

On Optimal Proportional Reinsurance and Investment in a Hidden Markov Financial Market

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Acta Mathematicae Applicatae Sinica 2017年第1期33卷 53-62页

作者： qing-bin MENG Xin ZHANG Jun-na bi School of Business Renmin University of China Department of Mathematics Southeast University School of Finance and Statistics East China Normal University

This paper investigates the optimal reinsurance and investment in a hidden Markov financial market consisting of non-risky （bond） and risky （stock） asset. We assume that only the price of the risky asset can be observed from the financial market. Suppose that the insurance company can adopt proportional reinsurance and investment in the hidden Markov financial market to reduce risk or increase profit. Our objective is to maximize the expected exponential utility of the terminal wealth of the surplus of the insurance company. By using the filtering theory, we establish the separation principle and reduce the problem to the complete information case. With the help of Girsanov change of measure and the dynamic programming approach, we characterize the value function as the unique solution of a linear parabolic partial differential equation and obtain the Feynman-Kac representation of the value function.

关键词： hidden Markov chain exponential utility Girsanov change of measure dynamic programming.

Synthesis and Crystal Structure of a Dinuclear Cu(Ⅱ) Complex [Cu(C_(13)H_9N_2O)Cl]_2·(CH_3CN)_2 with Ligand 2-Benzimidazol

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Chinese Journal of Structural Chemistry 2007年第2期26卷 149-152页

作者： LI qing-Xiang YANG Xiang-Liang XU Hui-bi Hubei Key Laboratory of Novel Chemical Reactor andGreen Chemical Technology Wuhan Institute of Technology Wuhan 430073 China College of Life Science Huazhong University of Science and Technology Wuhan 430074 China

A new dinuclear copper complex, [Cu（C13HgN2O）Cl]2.（CH3CN）2 （C30H24C12Cu2N6O2）, has been synthesized and characterized by X-ray structure determination. It crystallizes in the triclirile system, space group P1, with a = 7.6677（14）, b = 9.2375（17）, c = 11.227（2） ]A, α = 81.338（3）,β = 88.173（4）, γ = 66.199（3）°, V = 718.9（2） ]A^3, Z = 1, Mr = 698.53, F（000） = 354, Dc = 1.613 g/cm^3, μ（MoKa） = 1.705 mm^-1, the final R = 0.0645 and wR = 0.1364 for 2474 unique reflections with 1809 observed ones （I 〉 20（I））. In the title complex, each copper（H） atom is located at the center of a distorted tetrahedron consisting of four coordinate atoms （one nitrogen atom, two oxygen anions, and one chlorine atom）. Two copper（Ⅱ） atoms are bridged by two oxygen anions （O（1） and O（la）） of two phenolates to form a Cu（Ⅱ）-Cu（Ⅱ） binuclear entity, and the distance between two copper（Ⅱ） atoms is 3.0144（15） A.

关键词： 2-benzimidazol phenolate Cu(Ⅱ) complex crystal structure

Effects of Transition Metal Oxides on Thermal Conductivity of Mould Fluxes

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Journal of Iron and Steel Research International 2013年第11期20卷 27-32页

作者： QIU Xin XIE bing qing Xue-mei DIAO Jiang HUANG qing-yun WANG shui-bo College of Materials Science and Engineering Chongqing University Wuhan Iron and Steel Design and Research Institute Engineering Technology Company

The thermal conductivity of the mould fluxes containing transition metal oxides was measured by hotline method at different temperatures. The relationship between the thermal conductivity of mold fluxes and the contents of transition metal oxides was discussed. The synthetic slags were composed of 30.0% - 35.4%CaO, 34.7% - 38.6% SiO2, 6% Al2O3, 9% Na2O, 14.4% CaF2, 0-4% Cr2O3 and 0-8% MnO in mass percent. The results indicated that Cr2O3 and MnO had a negative effect on thermal conductivity of mold fluxes. The thermal conductivity of mold fluxes was about 0.25-0.55 W/（m · K） when the temperature reached 1 300 ℃, and it increased sharply to about 1.32-1.99 W/（m · K） when the temperature reduced from 1300 to 1000 ℃. The thermal conductivity of mold fluxes containing Cr2 O3 and MnO was 10 %- 25% lower than those of original fluxes. The decrease in thermal conductivity was attributed to the change of molecular structure of mold fluxes. In addition, the poor integrity and regulation of polycrystal structure, complexity of crystal structure, and effects of impurities in the boundary and lat- tice distortion leaded to the reduction in the thermal conductivity. Na2 CrO4, Mn2 SiO4 and other minor phases were also found in the samples containing Cr2O3 and MnO, respectively.

关键词： mould flux heat transfer transition metal oxide thermal conductivity

Study on the Method of Soil Productivity Assessment in Black Soil Region of Northeast China

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Agricultural Sciences in China 2009年第4期8卷 472-481页

作者： DUAN Xing-wu XIE Yun FENG Yan-jie YIN shui-qing State Key Laboratory of Earth Surface Processes and Resource Ecology School of Geography Beijing Normal University Beijing 100875P.R. China

The objective of this paper is to investigate a simple and practical method for soil productivity assessment in the black soil region of Northeast China. Firstly, eight kinds of physicochemical properties for each of 120 soil samples collected from 25 black soil profiles were analyzed using cluster and correlation analysis. Subsequently, parameter indices were calculated using physicochemical properties. Finally, a modified productivity index （MPI） model were developed and validated. The results showed that the suitable parameters for soil productivity assessment in black soil region of Northeast China were soil available water, soil pH, clay content, and organic matter content. Compared with original productivity index （PI） model, MPI model added clay content and organic matter content in parameters while omitted bulk density. Simulation results of original PI model and MPI model were compared using crop yield of land block where investigated soil profiles were located. MPI model was proven to perform better with a higher significant correlation with maize yield. The correlation equation between MPI and yield was： Y= 3.2002Ln（MP/）＋ 10.056, R^2 = 0.7564. The results showed that MPI model was an effective and practical method to assess soil productivity in the research area.

关键词： PI MPI soil productivity black soil region of Northeast China

Rice Homeobox Transcription Factor HOX1a Positively Regulates Gibberellin Responses by Directly Suppressing EL1

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Journal of Integrative Plant biology 2011年第11期53卷 869-878页

作者： bi-qing Wen Mei-qing Xing Hua Zhang Cheng Dai Hong-Wei Xue National Key Laboratory of Plant-Molecular Genetics Institute of Plant Physiology and Ecology Shanghai Institute for Biological Sciences the Chinese Academy of Sciences Shanghai 200032 China

Homeobox transcription factors are involved in various aspects of plant development, including maintenance of the biosynthesis and signaling pathways of different hormones. However, few direct targets of homeobox proteins have been identified. We here show that overexpression of rice homeobox gene HOXla resulted in enhanced gibberellin （GA） response, indicating a positive effect of HOXla in GA signaling. HOXla is induced by GA and encodes a homeobox transcription factor with transcription repression activity. In addition, HOXla suppresses the transcription of early flowering1 （EL1）, a negative regulator of GA signaling, and further electrophoretic mobility shift assay and chromatin immunoprecipitation analysis revealed that HOXla directly bound to the promoter region of EL1 to suppress its expression and stimulate GA signaling. These results demonstrate that HOXla functions as a positive regulator of GA signaling by suppressing EL1, providing informative hints on the study of GA signaling.

关键词： EL1 giberellin giberellin signaling HOXla homeobox.