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Numerical simulation of the seismic behavior of self-centering steel beam-column connections with bottom flange friction devices

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Earthquake Engineering and Engineering Vibration 2011年第2期10卷 229-238页

作者： guo Tong song Lianglong zhang guodong Key Laboratory of Concrete and Prestressed Concrete Structure Ministry of Education Southeast Univ. Nanjing 210096 China

A new type of steel moment resisting frame with bottom flange friction devices （BFFDs） has been developed to provide self-centering capacity and energy dissipation, and to reduce permanent deformations under earthquakes. This paper presents a numerical simulation of self-centering beam-column connections with BFFDs, in which the gap opening/closing at the beam-column interfaces is simulated by using pairs of zero-length elements with compression-only material properties, and the energy dissipation due to friction is simulated by using truss elements with specified hysteretic behavior. In particular, the effect of the friction bolt bearing against the slotted plate in the BFFDs was modeled, so that the increase in lateral force and the loss of friction force due to the bolt bearing could be taken into account. Parallel elastic-perfectly plastic gap （ElasticPPGap） materials in the Open System for Earthquake Engineering Simulation （OpenSees） were used with predefined gaps to specify the sequence that each bolt went into the bearing and the corresponding increase in bending stiffness. The MinMax material in OpenSees is used to specify the minimum and maximum values of strains of the ElasticPPGap materials. To consider the loss of friction force due to bok bearing, a number of parallel hysteretic materials were used, and the failure of these materials in sequence simulated the gradual loss of friction force. Analysis results obtained by using the proposed numerical model are discussed and compared with the test results under cyclic loadings and the seismic loading, respectively.

关键词： numerical simulation post tensioned self-centering moment resisting steel frame bottom flange frictiondevice bolt bearing

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Use of bionic inspired surfaces for aerodynamic drag reduction on motor vehicle body panels

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第7期12卷 543-551页

作者： Xiao-wen song guo-geng zhang Yun WANG Shu-gen HU Department of Mechanical Engineering Zhejiang University Hangzhou 310027 China

Inspired by the successful applications of biological non-smoothness,we introduced bionic non-smooth surfaces as appendices into vehicle body design,aiming to further reduce aerodynamic *** size range of the non-smooth units with pits and grooves was determined according to our analysis with the mechanisms underlying non-smooth unit mediated aerodynamic drag *** bionic non-smooth units reported here were designed to adapt the structure of a given vehicle body from the point of boundary layer control that reduces the burst and the loss of turbulent kinetic *** engine cover lid and vehicle body cap were individually treated with the non-smooth units,and the treated vehicles were subjected to aerodynamic drag coefficient simulation tests using the computational fluid dynamics(CFD) analysis *** simulation results showed that,in comparison with smooth surfaces,properly designed non-smooth surfaces can have greater effects on drag *** mechanism underlying drag reduction mediated by non-smooth surfaces was revealed by further analyses,in which the effects of non-smooth and smooth surfaces were directly compared.

关键词： Computational fluid dynamics(CFD) Bionics Non-smooth surface Aerodynamic drag reduction Vehicle body

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Magnesium single-atom catalysts with superbasicity

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Science China Chemistry 2023年第6期66卷 1737-1743页

作者： Xiang-Bin Shao Yao Nian song-song Peng guo-song zhang Meng-Xuan Gu You Han Xiao-Qin Liu Lin-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Magnesium-related solid bases have long been considered catalysts with weak or medium *** we report the fabrication of Mg single-atom catalysts with superbasicity for the first time.A sublimation-migration-anchoring strategy is employed,in which the Mg net is sublimated,transported by Ar,and trapped by defective graphene(producing Mg_(1)/G).Simulated and experimental results demonstrate that Mg single atoms are anchored on graphene in tetra-coordination,and Mg single atoms cooperating with C atoms give superbasicity,which differs from conventional alkali/alkaline earth metal oxides with basicity originating from O *** new solid base is highly active in the synthesis of dimethyl carbonate through transesterification of ethylene carbonate with methanol,which is usually catalyzed by strong *** turnover frequency value reaches 99.6 h^(-1) on Mg_(1)/G,which is much higher than that of traditional Mg-related counterparts(1.0–5.6 h^(-1))and even superior to that of typical Na and K-related solid superbases(29.8–36.2 h^(-1))under similar conditions.

关键词： solid superbase single Mg atoms heterogeneous catalysts transesterification reaction

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Fabrication of porous Zn_(2)TiO_(4)-ZnO microtubes and analysis of their acetone gas sensing properties

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Rare Metals 2021年第6期40卷 1528-1535页

作者： Xiao-Yan Chen Xin-Zhen Wang Feng-Jun Liu guo-song zhang Xiao-Jie song Jian Tian Hong-Zhi Cui School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Shandong Province Key Laboratory of Mine Mechanical Engineering Shandong University of Science and TechnologyQingdao 266590China

Porous Zn2 Ti04-ZnO microtubes have been successfully fabricated using chemical precipitation followed by a calcination process using a carbon fiber *** porous Zn_(2)TiO_(4)-ZnO micro tubes with a diameter of~4μm consisted of Zn_(2)TiO_(4) and ZnO *** displayed worm-like pore *** fibers played an important role during the porous Zn_(2)TiO_(4)-ZnO microtube formation *** porous and hollow structure of Zn_(2)TiO_(4)-ZnO provided abundant active sensing sites and channels for gas adsorption and *** porous Zn_(2)TiO_(4)-ZnO microtubes exhibited improved gas sensing properties for acetone when compared with pure *** Zn_(2)TiO_(4)-ZnO sensor response was 33.4 for 100μg·ml^(-1) acetone at the optimum operating temperature(370℃).This was~2.7 times higher than that of pure ***,the as-prepared porous Zn_(2)TiO_(4)-ZnO microtubes displayed sufficient long-term acetone stability and *** showed the potential application for acetone *** enhanced Zn_(2)TiO_(4)-ZnO gas sensing properties are due to the unique heterogeneous and porous structure,which was analyzed using the porous and band structure.

关键词： Zn_(2)TiO_(4) Zinc oxide Porous Heterostructure Sensors

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Using the Box-Behnken Response Surface Method to Optimize the Preparation and Characterization of Lavender and Fennel Volatile oilβ-cyclodextrin Form Inclusion Complex

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World Journal of Traditional Chinese Medicine 2018年第2期4卷 54-61页

作者： Yuan-Yuan Liu guo-song zhang Guang-Wei Zhu Ai-Ni-Wa-Er Aikemu Jia-Jia Ai Dong-Xun Li The National Pharmaceutical Engineering Center for Solid Preparation in Chinese Herbal Medicine Jiangxi University of Traditional Chinese Medicine Chinese Medicine Research Institute Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences Basic Medical College Xinjiang Medical University

Objective:The objective of this study is to study the best inclusion technology of Lavender-and fennel-mixed volatile oil by beta?cyclodextrin(β-CD) and characterize the final product ***:Using the saturated water solution method,the volatile β-CD inclusion complex was *** effect of volatile oil weight ratio,inclusion temperature and inclusion time on the inclusive quality was studied by measuring the yield of inclusion and inclusion rate of volatile oil as evaluation *** preparation method of inclusion complex was then optimized by the Box-Behnken response surface *** inclusion complex was characterized by ultraviolet spectrophotometry,thin-layer chromatography,thermogravimetry and differential thermal analysis,and the microscopic imaging ***:The optimized conditions were the weight ratio of β-CD to volatile oil was 8.13:1(g/ml).The inclusion temperature was 44°*** inclusion time was 1 ***:We were able to produce an inclusion complex with high inclusion rate of volatile oil and high yield of inclusion using the preparation method mentioned ***,the method can also improve the stability of volatile oil in abnormal savda *** study can provide a good reference for the development of new preparations.

关键词： Fennel inclusion complex lavender response surface method volatile oil β-cyclodextrin

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Effects of TiB_2+TiC content on microstructure and wear resistance of Ni55-based composite coatings produced by plasma cladding

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Transactions of Nonferrous Metals Society of China 2019年第1期29卷 132-142页

作者： Xin-jie zhang Hong-zhi CUI Jia-feng WANG guo-song zhang Yu-qiao ZHAO Kang SUN School of Materials Science and Engineering Shandong University of Science and Technology Qingdao 266590 China

TiB2-TiC reinforced Ni55 matrix composite coatings were in-situ fabricated via plasma cladding on steels using Ti, B4C, and Ni55 as precursor materials at different proportions. Effects of TiB2+TiC content of ceramics phase on the microstructure and wear resistance were studied. The results showed that ceramic phases TiB2 and TiC were in-situ synthesized by plasma cladding, and the ceramic phase content significantly affected tribological performance and the wear mechanism of coatings under different loads. The composite ceramics protected coatings from further delamination wear by crack-resistance under a load of 30 N. Severe abrasive wear and adhesive wear were prevented when the load increased to 60 N because of the high hardness and strength of ceramic phases. Moreover, a compacted layer appeared on the wear surface of coatings with high content of ceramic phases, which effectively decreased the friction coefficient and wear rate. The TiB2-TiC composite ceramics significantly improved the wear performance of metal matrix composite coatings by different mechanisms under loads of 30 and 60 N.

关键词： metal matrix composite coating plasma cladding microstructure tribological behavior wear mechanism

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中国高速铁路客票超售的探讨

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铁道运输与经济 2008年第8期30卷 87-89页

作者：郭颂章广州铁路集团公司运输处广东广州510088

在基于高速铁路与民航的技术经济特征比较的基础上,提出中国高速铁路的售票方式可以借鉴国际民航业的做法——实行客票超售,并运用数理统计方法给出了确定最佳客票超售量的简易近似算法,最后针对高速铁路客票超售的实施,提出建议。

关键词：高速铁路旅客运输客票超售

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Outcome of in vitro fertilization in endometriosis-associated infertility： a 5-year database cohort study

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Chinese Medical Journal 2012年第15期125卷 2688-2693页

作者： LIN Xiao-na WEI Min-ling TONG Xiao-mei XU Wei-hai ZHOU Feng HUANG Qiong-xiao WEN guo-feng zhang song-ying Assisted Reproduction Unit Department of Obstetrics andGynecology Sir Run Run Shaw Hospital Zhejiang UniversitySchool of Medicine Hangzhou Zhejiang 310016 China

Background Endometriosis affects natural fertility through various approaches, and in vitro fertilization （IVF） is a good treatment. But the IVF result of endometriosis patients is still under debate. We investigated the effect of endometriosis on IVF by analyzing the data from a single reproductive center. Methods A retrospective, database-searched cohort study was performed. Relevant information was collected from the electronic records of women who underwent IVF/intracytoplasmic sperm injection between January 2006 and December 2010 in the Assisted Reproductive Unit of Sir Run Run Shaw Hospital. Patients with endometriosis were enrolled the study group. The rest of the women formed the control group. The main outcome was the clinical pregnancy rate. Secondary outcomes were oocytes retrieved number, fertilization rate, high-quality embryo rate, number of high-quality embryo for embryo transplantation, and implantation embryo/high-quality embryo ratio （IE/HQE ratio）. Comparisons were performed by the z2-test and independent t-test. Results The endometriosis group （n=177） had a markedly lower oocytes retrieved number, fertilization rate, implantation rate, and clinical pregnancy rate （7.6_＋5.1, 63.6%, 27.7%, and 45.2%, respectively） compared with the non-endometriosis group （n=4267; 11.8＋7.3, 68.4%, 36.2%, and 55.2%, respectively）. Stratified analysis showed that this difference was found in the subgroup younger than 35-years old, while only fertilization rate and implantation rate were different in the elder subgroup. The ratio of high-quality embryos transferred is lower in endometriosis group （53.7% vs. 71.8%, P 〈0.05）, but there is no difference in IE/HQE ratio between two groups. There is no significant difference in fertilization rate, implantation rate, and clinical pregnancy rate between mild and severe endometriosis patients. Conclusions Endometriosis patients suffer a decreasing IVF pregnancy rates mainly caused by reducing oocytes number and fertilization

关键词： fertilization in vitro, endometriosis pregnancy rate cohort study

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面肩肱型肌营养不良症一例大家系20年随访报告

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中国优生与遗传杂志 2006年第1期14卷 112-113页

作者：宋国璋陕西省人民医院外科西安710068

目的了解面肩肱型肌营养不良症一例大家系的发展形势,寻求防治方法。方法实际访查该家系所有成员,重绘家系谱图。结果该家系出现第Ⅶ代;现共418人:第Ⅵ代新发病3人:现存患者9人:因先天性疾病早死产15人。结论本病尚无法治疗,危害严重,... 详细信息

目的了解面肩肱型肌营养不良症一例大家系的发展形势,寻求防治方法。方法实际访查该家系所有成员,重绘家系谱图。结果该家系出现第Ⅶ代;现共418人:第Ⅵ代新发病3人:现存患者9人:因先天性疾病早死产15人。结论本病尚无法治疗,危害严重,应依据产前诊断和有效措施,终止本病的继续传递。

关键词：面肩肱型肌营养不良症常染色体显性遗传大家系

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C-X-C chemokine receptor type 5+CD8+T cells as immune regulators in hepatitis Be antigen-positive chronic hepatitis B under interferonalpha treatment

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World Journal of Gastroenterology 2025年第3期31卷 73-83页

作者： Zhen-Yu Xu Zhong-Shang Dai guo-Zhong Gong Min zhang Department of Infectious Diseases Second Xiangya HospitalCentral South UniversityChangsha 410011Hunan ProvinceChina Institute of Hepatology and Department of Infectious Diseases The Second Xiangya HospitalCentral South UniversityChangsha 410011Hunan ProvinceChina

BACKGROUND C-X-C chemokine receptor type 5(CXCR5)+CD8+T cells represent a unique immune subset with dual roles,functioning as cytotoxic cells in persistent viral infections while promoting B cell *** their importance,the specific role of CXCR5+CD8+T cells in chronic hepatitis B(CHB),particularly during interferon-alpha(IFN-α)treatment,is not fully *** study aims to elucidate the relationship between CXCR5+CD8+T cells and sustained serologic response(SR)in patients undergoing 48 weeks of pegylated IFN-α(peg-IFN-α)treatment for *** To elucidate the relationship between CXCR5+CD8+T cells and sustained SR in patients undergoing 48 weeks of peg-IFN-αtreatment for *** This study enrolled 60 patients with hepatitis Be antigen(HBeAg)-positive CHB undergoing 48 weeks of peg-IFN-α*** were assessed for eligibility based on criteria such as persistent HBsAg-positive status for at least six months,HBeAb-negative,hepatitis B virus DNA levels exceeding 2×104 copies/mL,and alanine aminotransferase(ALT)levels between 2 and 10 times the upper limit of *** samples were collected at baseline and at weeks 12,24,48,and a 24-week treatment-free follow-up(week 72)to measure serum interleukin(IL)-21 concentration via ELISA and to analyze CXCR5 and programmed death-ligand 1(PD-L1)expression on CD8+T cells by flow cytometry,CXCR5 is a chemokine receptor that directs immune cells to specific tissues,while PD-L1 is a protein that regulates immune responses by inhibiting T cell *** Patients with CHB exhibited significantly lower levels of circulating CXCR5+CD8+T cells compared to healthy controls(P<0.01).Notably,CXCR5+CD8+T cells were prominently expressed in patients who achieved sustained SR compared to non-SR(NSR).A significant correlation was observed between CXCR5 and PD-L1 expression(r=-0.189,P=0.002).However,there was no significant correlation between serum IL-21 levels and CXCR5+CD8+lymphocytes(r=-0.03,P=0.62

关键词： C-X-C chemokine receptor type 5 Programmed death-ligand 1 Interleukin-21 Pegylated interferon-alpha Chronic hepatitis B

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