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Rotational Isomeric State Model of Poly(vinylidene chloride) Based Upon ab Initio Electronic Structure Calculations

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Chemical Research in Chinese Universities 2009年第1期25卷 108-111页

作者： ZHANG zhi-jie lIU Yu-hua lü Zhong-yuan lI Ze-sheng Institute of Theoretical Chemistry State Key Laboratory of Theoretical and Computational Chemistry Jilin University Changchun 130021 P. R. China

The rotational isomeric state（RIS） model was constructed for poly（vinylidene chloride）（PVDC） based on quantum chemistry calculations. The statistical weighted parameters were obtained from RIS representations and ab initio energies of conformers for model molecules 2,2,4,4-tetrachloropentane（TCP） and 2,2,4,4,6, 6-hexachloroheptane（HCH）. By employing the RIS method, the characteristic ratio C∞ was calculated for PVDC. The calculated characteristic ratio for PVDC is in good agreement with experiment result. Additionally, we studied the influence of the statistical weighted parameters on C∞ by calculating δC∞/δlnw. According to the values of δC∞/δlnw, the effects of second-order Cl-CH2 pentane type interaction and C1--C1 long range interaction on C∞ were found to be important. In contrast, first-order interaction is unimportant.

关键词： Ab initio calculations Characteristic ratio Poly(vinylidene chloride)

EXPERIMENTAl STUDY ON SOIl MOISTURE USING DUAl-FREQUENCY MICROWAVE RADIOMETER

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Chinese Geographical Science 2006年第1期16卷 83-86页

作者： GUAN zhi ZHAO Kai SONG Dong-sheng Nartheast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 P.R.China Graduate School of Chinese Academy of Sciences Beijing 100049 P.R.China

An experiment of measuring soil moisture was carried out by using dual-frequency microwave radiometer designed by the authors. The measured data were analyzed by using statistical regression method and the empirical regression model of retrieving soil moisture in l-band and C-band was developed. The soil moisture in a rainfall event was retrieved using the experiential regression model, which is consistent well with the field sampling value. The results show that when soil moisture is lower than 75%, the brightness temperature is linear with soil moisture. However, when soil moisture is higher than 75%, the brightness temperature is not linear with soil moisture, so it is difficult for microwave radiometer to measure the changes of soil moisture. The experiment verifies the effectiveness and feasibility of microwave remote sensing soil moisture. Although this method for linear regression based on the data measured with the radiometer is simple, and has strong adaptability, generally it has only local application value, and lacks universal applicability for different areas and different conditions.

关键词： soil moisture dual-frequency microwave radiometer brightness temperature

Mitigation of greenhouse gases released from mining activities:A review

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International Journal of Minerals,Metallurgy and Materials 2021年第4期28卷 513-521页

作者： li-yuan liu Hong-guang Ji Xiang-feng lü Tao Wang sheng zhi Feng Pei Dao-lu Quan Beijing Key laboratory of Urban Underground Space Engineering University of Science and Technology BeijingBeijing 100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Department of Energy and Mineral Engineering EMS Energy Institute and G3 CenterPennsylvania State UniversityUniversity ParkPA 16802USA

Climate changes that occur as a result of global warming caused by increasing amounts of greenhouse gases(GHGs)released into the atmosphere are an alarming *** greenhouse gas emissions is critically important for the current and future status of mining *** mining industry is one of the significant contributors of greenhouse *** essence,anthropogenic greenhouse gases are emitted directly during the actual mining and indirectly released by the energy-intensive activities associated with mining equipment,ore transport,and the processing ***,we reviewed both direct and indirect GHG emissions to analyze how mining contributes to climate *** addition,we showed how climate change impacts mineral *** assessment was performed using a GHG inventory model for the gases released from mines undergoing different product life *** also elucidate the key issues and various research outcomes to demonstrate how the mining industry and policymakers can mitigate GHG emission from the mining *** review concludes with an overview of GHG release reduction and mitigation strategies.

关键词： greenhouse gas emission greenhouse gas reduction mining climate change life cycle assessment mitigation strategy

Synthesis and Crystal Structure of a Novel Manganese Coordination Polymer Constructed by 3,5-Dimethylbenzoic Acid with 4,4'-Bipyridine

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Chinese Journal of Structural Chemistry 2006年第10期25卷 1213-1216页

作者： ZHANG Chun-Hua CHEN Man-sheng KUANG Dai-zhi Department of Chemistry and Materials Science Hengyang Normal University Hengyang 421008 China

A novel manganese coordination polymer [Mn（l）2（bipy）]n （Hl = 3,5-dimethylbenzoic acid, 4,4＇-bipy = 4,4＇-bipyridine） has been synthesized by a hydrothermal method. The molecular and crystal structures were determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group C2/c with a = 2.0996（8）, b = 1,1835（5）, c = 0.9958（4） nm, β = 110.161（5）°, V = 2,3229（16） nm^3, Z = 4, C28H26MnN2O4, Mr = 509.45, Dc= 1.457 g/cm^3,μ = 0.607 mm^-1, F（000） = 1060, Rim = 0.0566, R = 0.0334 and wR = 0.1078. In the crystal the manganese atom is six-coordinated by two nitrogen atoms from 4,4＇-bipy and four oxygen atoms from 3,5-dimethylbenzolate molecules, completing an octahedral geometry. The 4,4＇-bipy molecules bridge the infinite chain [Mn（l）2（bipy）]n to form a two-dimensional layer.

关键词： manganese coordination polymer hydrothermal synthesis crystal structure

Influences of aerodynamic loads on hunting stability of high-speed railway vehicles and parameter studies

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Acta Mechanica Sinica 2014年第6期30卷 889-900页

作者： Xiao-Hui Zeng Han Wu Jiang lai Hong-zhi sheng Key laboratory for Mechanics in Fluid Solid Coupling Systems Institute of Mechanics Chinese Academy of Sciences

The influences of steady aerodynamic loads on hunting stability of high-speed railway vehicles were investigated in this study.A mechanism is suggested to explain the change of hunting behavior due to actions of aerodynamic loads：the aerodynamic loads can change the position of vehicle system（consequently the contact relations）,the wheel/rail normal contact forces,the gravitational restoring forces/moments and the creep forces/moments.A mathematical model for hunting stability incorporating such influences was developed.A computer program capable of incorporating the effects of aerodynamic loads based on the model was written,and the critical speeds were calculated using this *** dependences of linear and nonlinear critical speeds on suspension parameters considering aerodynamic loads were analyzed by using the orthogonal test method,the results were also compared with the situations without aerodynamic *** is shown that the most dominant factors a ff ecting linear and nonlinear critical speeds are different whether the aerodynamic loads considered or *** damping of yaw damper is the most dominant influencing factor for linear critical speeds,while the damping of lateral damper is most dominant for nonlinear *** the influences of aerodynamic loads are considered,the linear critical speeds decrease with the rise of cross wind velocity,whereas it is not the case for the nonlinear critical *** variation trends of critical speeds with suspension parameters can be significantly changed by aerodynamic *** actions of aerodynamic loads and suspension parameters also a ff ect the critical *** effects of such joint action are more obvious for nonlinear critical speeds.

关键词： Hunting stability linear critical speed Nonlinear critical speed Aerodynamic loads Suspension parameters Orthogonal experimental design

Effect of deep cryogenic treatment on martensitic lath refinement and nano-twins formation of low carbon bearing steel

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Journal of Iron and Steel Research International 2020年第1期27卷 105-113页

作者： Xin-yang lü zhi-wei Wu Xiao He Jun li Shao-hong li Mao-sheng Yang Kun-yu Zhao Faculty of Material Science and Engineering Kunming University of Science and TechnologyKunming 650093YunanChina Institute for Special Steels Central Iron and Steel Research InstituteBeijing 100081China

The effect of heat treatment and deep cryogenic treatment on microstructural evolution of low carbon martensitic bearing steel was *** experimental results showed that the lath martensite was obtained by quenching and a few twins as substructures formed in some martensitic *** rudiment of sub-interfaces of martensitic lath was formed in the highdensity dislocation regions after deep cryogenic treatment;meanwhile,the number of twins increased,especially in the highdensity dislocation *** phenomenon is due to the increase in internal stress caused by cryogenic *** tempering,the rudiment of sub-interface further evolved into the martensitic lath boundary,and thus the original martensitic laths were *** twins formed by cryogenic treatment did not disappear after *** addition,small quantities of annealing twins formed in tempering *** laths morphology and substructures in different stages of the heat and deep cryogenic treatment were observed by tninsmission electron microscopy.

关键词： low carbon bearing steel-Deep cryogenic treatment Internal stress Sub-interface Nano-twin

Effect of Mo and cold forging deformation on strength and ductility of cobalt-based alloy l605

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Journal of Iron and Steel Research International 2024年第7期31卷 1811-1823页

作者： Zhong-lin Wang zhi-hua Gong Quan li Han-sheng Bao School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014017Inner MongoliaChina Institute of Special Steels Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China

Mo element was added to cobalt-based alloy l605,and cold forging deformation was *** effects of the addition and cold forging deformation on the microstructure and mechanical properties of the alloy were studied by thermodynamic calculation,electron backscatter diffraction,transmission electron microscopy,and X-ray *** stacking fault energy(SFE)of the alloy decreased after the addition,and the formation of stacking faults and intersections were promoted to improve the strength and *** tensile strength of the alloy with Mo increased from 1190 to 1702 MPa after 24%cold deformation,producing significant work *** strengthening mechanism is strain-induced martensitic transformation(SIMT)and deformation *** alloy,combined with Mo and after 24%deformation,had both high strength and ductility in comparison with the original cobalt-based alloy *** is attributed to the lower SFE which caused the increase in stacking fault *** the tensile process,theε-hcp phase was easily generated at the stacking fault to reduce the stress concentration and increase the *** SIMT by adjusting the density of stacking faults can improve the mechanical properties of cobalt-based ***ε-hcp phase,the interaction between deformation twins and dislocations,and the interaction between e-hcp phases during cold forging deformation caused local stress concentration,lowering ductility and toughness.

关键词： Cobalt-based alloy-Stacking fault energy Strain-induced martensitic transformation Deformation twin Cold forging deformation

Hsa-miR-214-3p inhibits breast cancer cell growth and improves the tumor immune microenvironment by downregulating B7H3

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Oncology research 2025年第1期33卷 103-121页

作者： Yan lu Kang Wang Yuanhong Peng Meng Chen lin Zhong luji Huang F U Cheng Xindan sheng Xin Yang Manzhao Ouyang George A Calin zhiwei He China-America Cancer Research Institute Guangdong Medical University Dongguan 523808 China. GCP Center Shunde Hospital Southern Medical University (The First People's Hospital of Shunde Foshan) Shunde 528300 China. Department of Gastrointestinal Surgery Shunde Hospital Southern Medical University (The First People's Hospital of Shunde Foshan) Shunde 528300 China. The Second School of Clinical Medicine Southern Medical University Guangzhou 510080 China. Department of Translational Molecular Pathology The University of Texas MD Anderson Cancer Center Houston TX 77030 USA. Department of Oncology Shunde Hospital Southern Medical University (The First People's Hospital of Shunde Foshan) Shunde 528300 China.

Background:Immune checkpoint inhibitors play an important role in the treatment of solid tumors, but the currently used immune checkpoint inhibitors targeting programmed cell death-1 (PD-1), programmed cell death ligand-1 (PD-l1), and cytotoxic T-lymphocyte antigen-4 (CTlA-4) show limited clinical efficacy in many breast cancers. B7H3 has been widely reported as an immunosuppressive molecule, but its immunological function in breast cancer patients remains unclear.Methods:We analyzed the expression of B7H3 in breast cancer samples using data from the Cancer Genome Atlas Program (TCGA) and the Gene Expression Omnibus (GEO) databases. MicroRNAs were selected using the TarBase, miRTarBase, and miRBase databases. The regulatory role of the microRNA hsa-miR-214-3p on B7H3 was investigated through dual-luciferase reporter assays, which identified the specific action sites of interaction. The expression levels of B7H3 and hsa-miR-214-3p in human breast cancer tissues and adjacent normal tissues were quantified using Western blotting and quantitative PCR (qPCR). experiments were performed to observe the effects of modulating the expression of B7H3 or hsa-miR-214-3p on breast cancer cell proliferation and apoptosis. Additionally, the regulatory impact of hsa-miR-214-3p on B7H3 was examined. Enzyme-linked immunosorbent assays (ElISA) and flow cytometry were employed to assess the effects of co-cultured breast cancer cells and normal human peripheral blood mononuclear cells (PBMCs) on immune cells and associated cytokines.Results:In breast cancer tissues, the expression level of B7H3 is inversely correlated with that of hsa-miR-214-3p, as well as with the regulatory effects on breast cancercell behavior. Hsa-miR-214-3p was found to inhibit breast cancer cell growth by downregulating B7H3. Importantly, our research identified, for the first time, two binding sites for hsa-miR-214-3p on the 3' UTR of B7H3, both of which exert similar effects independently. Co-culture experime

关键词： B7H3 Breast cancer Hsa-miR-214-3p Immunotherapy

Effects of Br^- and I^- concentrations on Zn electrodeposition from ammoniacal electrolytes

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International Journal of Minerals,Metallurgy and Materials 2015年第7期22卷 682-687页

作者： zhi-mei Xia sheng-hai Yang liang-hong Duan Mo-tang Tang School of Metallurgy and Environment Central South University School of Metallurgical Engineering Hunan University of Technology

The effects of Br- and I- concentrations on the cell voltage, anodic polarization, current efficiency （CE）, and energy consumption （EC） of zinc electrodeposition from ammoniacal ammonium chloride solutions were investigated. The surface morphology of zinc deposits was also examined. Scanning electron microscopy （SEM） and X-ray diffraction （XRD） were used to characterize the morphology of zinc deposits and the phase of anodic sediments produced during electrolysis. The results clearly showed that the CE slightly increased from approximately 95.12% in the absence of F and Br- to 97.08% in the presence of 10 g·l-1 Br; in contrast, the CE significantly decreased to less than 83% in the presence of 10 g·l-1 I- . The addition of Br and I- positively affected the EC, which decreased from 2514 kW·h·t-1 to approximately 2300 kW·h·t-1. The results of anodic polarization measurements showed that the voltage drops were 130 and 510 mV when the concentrations of Br- and I- were 10 g·l-1 at a eUlTent density of 400 A·m2, respectively. SEM images showed that the addition of Br- and I- caused different crystal growth mechanisms, which resulted in the production of compact and smooth zinc deposits. The anodic reactions of I were also studied.

关键词： zinc electrodeposition bromide iodide ammonium chloride current efficiency energy consumption