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Journal of Magnesium and Alloys 2022年第10期10卷 2745-2760页

作者： Chao Cui Wencong Zhang Wenzhen chen Jian He xuemin chen Jiabin Hou School of Materials Science and Engineering Harbin Institute of TechnologyWeihai 264209China Weihai Lightweight Materials and Forming Engineering Research Center Weihai 264209China Harbin Institute of Technology-Weihai Innovation Park Weihai 264209China

Multi-direction impact forging(MDIF)was applied to the as-extruded ZK60 Mg alloy,and the microstructure,texture evolution and yield strength symmetry were investigated in the current study.The results showed that the average grain size of forged piece was greatly refined to 5.3μm after 120 forging passes,which was ascribed to the segmenting effect of{10–12}twins and the subsequent multiple rounds of dynamic recrystallization(DRX).A great deal of{10–12}twins were activated at the beginning of MDIF process,which played an important role in grain refinement.With forging proceeding,continuous and discontinuous DRX were successively activated,resulting in the fully DRXed microstructure.Meanwhile,the forged piece exhibited a unique four-peak texture,and the initial//ED fiber texture component gradually evolved into multiple texture components composed of//FFD(first forging direction)and//FFD texture.The special strain path was the key to the formation of the unique four-peak texture.The{10–12}twinning and basal slip were two dominant factors to the evolution of texture during MDIF process.Grain strengthening and dislocation strengthening were two main strengthening mechanisms of the forged piece.Besides,the symmetry of yield strength was greatly improved by MDIF process.

关键词： Multi-directional impact forging Twinning Dynamic recrystallization Texture Yield strength symmetry

P-band center theory guided activation of MoS_(2) basal S sites for pHuniversal hydrogen evolution

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Nano Research 2023年第5期16卷 6228-6236页

作者： Chao Meng Yuanfeng Gao Yue Zhou Kang Sun Yanmin Wang Ye Han Qianqian Zhao xuemin chen Han Hu Mingbo Wu State Key Laboratory of Heavy Oil Processing Institute of New EnergyChina University of Petroleum(East China)Qingdao 266580China College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China College of Energy Storage Technology Shandong University of Science and TechnologyQingdao 266590China Institute of Chemical Industry of Forest Products Chinese Academy of ForestryNanjing 210042China School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China College of Science Hebei University of Science and TechnologyShijiazhuang 050018China

The edge S sites of thermodynamically stable 2H MoS_(2)are active for hydrogen evolution reaction(HER)but the active sites are scarce.Despite the dominance of the basal S sites,they are generally inert to HER because of the low p-band center.Herein,we reported a synergistic combination of phase engineering and NH_(4)^(+) intercalation to promote the HER performance of MoS_(2).The rational combination of 1T and 2H phases raises the p-band center of the basal S sites while the intercalated NH4+ions further optimize and stabilize the electronic band of these sites.The S sites with regulated band structures afford moderate hydrogen adsorption,thus contributing to excellent HER performance over a wide pH range.In an acid medium,this catalyst exhibits a low overpotential of 169 mV at 10 mA·cm^(−2)and Tafel slope of 39 mV·dec^(−1)with robust stability,superior to most of recently reported MoS_(2)-based non-noble catalysts.The combined use of in/ex-situ characterizations ravels that the appearance of more unpaired electrons at the Mo 4d-orbital reduces the d-band center which upshifts the p-band center of the adjacent S for essentially improved HER performance.This work provides guidelines for the future development of layered transition-metal-dichalcogenide catalysts.

关键词： molybdenum disulfide p-orbital electron structure basal S sites hydrogen evolution synergistic mechanism

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数字检察的法律定位、运行逻辑及风险规制

兰州学刊 2024年第2期 106-121页

作者：陈学敏天津大学法学院天津大学中国绿色发展研究院

数字检察的法律定位是法律监督。该定位是在不违背检察机关宪法地位的基础上,对社会发展的回应,对履职的自省,既与“四大检察”“十大业务”的架构相契合,也与《中共中央关于加强新时代检察机关法律监督工作的意见》对检察机关的定性保... 详细信息

数字检察的法律定位是法律监督。该定位是在不违背检察机关宪法地位的基础上,对社会发展的回应,对履职的自省,既与“四大检察”“十大业务”的架构相契合,也与《中共中央关于加强新时代检察机关法律监督工作的意见》对检察机关的定性保持一致。数据与监督各自的规律与准则要求数字检察既要遵循数据的规律性,也不可违背法律监督的准则,且后者起着决定性作用,这是数字检察的运行逻辑。数字检察为数据预测下的监督功能延伸提供了空间,但也带来技术至上、数据不安全、监督越界等潜在风险。为规制风险,必须实施规则之治,统筹推进技术赋能与制度规制。一方面提倡数字正义以促进制度理性,另一方面以保护数据法益实现数据安全,同时,坚持法定主义下的比例原则以厘清权力边界。

关键词：数字检察法律定位法律监督数据法益数据安全

Abnormal expression of c-Myc in human bronchial epithelial cells malignantly transformed by anti-BPDE

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Frontiers of Medicine 2008年第4期2卷 380-385页

作者： Juan FU Yiguo JIANG xuemin chen Department of Occupational and Environmental Health the Ministry of Education Key Laboratory of Environment and HealthSchool of Public HealthTongji Medical College of Huazhong University of Science and TechnologyWuhan 430030China Institute for Chemical Carcinogenesis Guangzhou Medical CollegeGuangzhou 510182China

Anti-benzo[a]pyrene-7,8-diol-9,10-epoxide(anti-BPDE)is a metabolite of benzo[a]pyrene(B[a]P)and acts as a potent mutagen in mammalian systems.However,molecular mechanisms related to anti-BPDE-induced carcinogenesis are poorly understood.Here,we investigated the expression of proto-oncogene c-myc in human bronchial epithelial cells(16HBE-T)transformed by exposure to anti-BPDE.The levels of mRNA and pro-tein of c-Myc were examined in the 16HBE-T and vehicle-treated control cells(16HBE-N)by using different meth-ods respectively,including reverse transcriptase-polymer-ase chain reaction(RT-PCR),quantitative real-time PCR(Q-PCR),western blot and immunocytochemical meth-ods.The level of c-myc mRNA appeared to be signifi-cantly increased in 16HBE-T,as compared with those of the 16HBE-N.Likewise,the expression of c-Myc protein was significantly enhanced as compared with those of the control cells.Moreover,the localization of c-Myc protein shows mainly nuclear staining in 16HBE-T.In conclu-sion,the abnormal expression of c-Myc was present in anti-BPDE malignantly transformed 16HBE cells,which may be involved in the carcinogenesis molecular mech-anism of anti-BPDE.

关键词： anti-benzo(a)pyrene diol epoxide-deoxygua-nosine transformed cell c-Myc proteins carcinogenesis

Robust control for a class of nonlinear networked systems with stochastic communication delays via sliding mode conception

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控制理论与应用（英文版） 2010年第1期8卷 34-39页

作者： Lifeng MA Zidong WANG xuemin chen Zhi GUO School of Automation Nanjing University of Science and Technology Nanjing Jiangsu 210094 China Department of Information Systems and Computing Brunel University Uxbridge Middlesex UB8 3PH UK Department of Engineering Technology Texas Southern University Houston TX 77004 USA

This paper deals with the robust control problem for a class of uncertain nonlinear networked systems with stochastic communication delays via sliding mode conception （SMC）. A sequence of variables obeying Bernoulli distribution are employed to model the randomly occurring communication delays which could be different for different state variables. A discrete switching function that is different from those in the existing literature is first proposed. Then, expressed as the feasibility of a linear matrix inequality （LMI） with an equality constraint, sufficient conditions are derived in order to ensure the globally mean-square asymptotic stability of the system dynamics on the sliding surface. A discrete-time SMC controller is then synthesized to guarantee the discrete-time sliding mode reaching condition with the specified sliding surface. Finally, a simulation example is given to show the effectiveness of the proposed method.

关键词： Sliding mode control Nonlinear systems Networked systems Stochastic communication delays

Co8W6Mo5Cr4V3粉末高速钢的热变形行为

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粉末冶金材料科学与工程 2024年第1期29卷 11-19页

作者：杨礼林陈学敏陈朔赵莉萍内蒙古科技大学材料与冶金学院包头014010

采用熔炼、电渣重熔和气雾化法制备Co8W6Mo5Cr4V3粉末,再通过热等静压制备Co8W6Mo5Cr4V3粉末高速钢。在不同变形条件下进行热压缩实验,研究粉末高速钢的热变形行为,根据获得的应力-应变曲线,建立热变形本构方程,绘制热加工图。结果表明:... 详细信息

采用熔炼、电渣重熔和气雾化法制备Co8W6Mo5Cr4V3粉末,再通过热等静压制备Co8W6Mo5Cr4V3粉末高速钢。在不同变形条件下进行热压缩实验,研究粉末高速钢的热变形行为,根据获得的应力-应变曲线,建立热变形本构方程,绘制热加工图。结果表明:Co8W6Mo5Cr4V3粉末高速钢的流变应力随变形温度升高或应变速率减小而减小;通过本构方程预测的流变应力和实验得到的流变应力间的相关系数为0.995,可用此方程对粉末高速钢在不同变形条件下的应力进行预测;根据热加工图,粉末高速钢最优的变形温度为1 100~1 150℃,应变速率为0.1~1.0 s^(-1)。

关键词： Co8W6Mo5Cr4V3 粉末高速钢热变形本构方程热加工图

Numerical Study on the Leakage and Diffusion Characteristics of Low-Solubility and Low-Volatile Dangerous Chemicals from Ship in Inland Rivers

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Computer Modeling in Engineering & Sciences 2020年第4期123卷 217-235页

作者： Shuifen Zhan Mingchao Wang Min Wang Qianqian Shao Zefang Zhang Wenxin Jiang xuemin chen Lanzhou Jiaotong University Lanzhou730070China Tianjin Research Institute for Water Transport Engineering M.O.T.Tianjin300456China Tianjin Dongfang Tairui Technology Co.Ltd. Tianjin300192China Guangdong University of Petrochemical Technology Maoming525000China Beijing Computational Science Research Center Beijing100193China

Considering the accidents of ships for dangerous chemicals transportation in inland rivers,a numerical method for the simulation of the leakage and diffusion processes of dangerous chemicals in inland rivers is proposed in this paper.Geographic information,such as rivers and buildings in the model,is obtained through Google Earth and structures of rivers and buildings are described by Auto CAD.In addition,the Fluent is adopted to simulate the leakage and diffusion processes of the dangerous chemicals where the standard k-εmodel is used to calculate the turbulent flow.Considering the interaction between chemicals and water,the VOF method is used to describe the leakage,drift and diffusion process of dangerous chemicals groups on the water surface.Taking a section of the Yangtze River as an example,the leakage and diffusion processes from a ship carrying 3,000 tons of low-solubility and low-volatile dangerous chemicals are studied,and the characteristics of leakage and diffusion are analyzed in detail.During the simulation,the area of the maximum group of leaked dangerous chemicals reaches up to about 1800 m2,and the number reaches up to 45.Furthermore,the influence of density,viscosity,water velocity and leakage velocity on the leakage and diffusion processes is investigated in this paper.

关键词： Inland rivers low-solubility and low-volatile dangerous chemicals leakage and diffusion VOF.

Analyses of levels of thyroid hormones and its receptor expression in puerperants and newborns from an e-waste dismantling site

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Frontiers of Medicine 2008年第3期2卷 276-282页

作者： Ying JU Guojian XU Lan chen Qi JIANG Liping LI Kedi YANG xuemin chen Department of Occupational and Environmental Health and the MOE Key Lab of Environment and Health School of Public HealthHuazhong University of Science&TechnologyWuhan 430030China Research Center for Injury Prevention Shantou University Medical CollegeShantou 515031China

In this study,the serum levels,including thyr-oid hormones free triiodothyronine(FT3),free thyroxine(FT4),thyroid stimulating hormone(TSH)among the sub-jects from the exposed group(n 548)and the control group(n 545)were detected by immuno radiometric assay(IRMA).The expression levels of TRa1,TRb1,TSHR mRNA in placentas and umbilical cords were detected by fluorescent quantitative real-time PCR(FQ-PCR).The correlations between the thyroid hormone levels in maternal serum and umbilical serum,and between the expression levels of its receptors mRNA in placentas and umbilical cords were determined.We found that the FT4 levels of both maternal serum and umbilical cord serum in the exposed group were lower than those in the control(P<0.05).However,the increased TSH levels in the exposed group had statistically significance com-pared to those in the control group(P<0.05).The TRa1 and TRb1 mRNA levels both in placentas and umbilical cords in the exposed group were lower than those in the control group(P<0.05 and 0.01).How-ever,the TSHR mRNA levels in the exposed group were significantly different compared to those in the control group(P<0.01).The serum FT4 and TSH levels of par-turient women were positively correlated with those of the newborns in both groups(P<0.05 and 0.01).The mRNA levels of TRa1,TRb1 and TSHR in the placentas were positively correlated with those in umbilical cords in both groups(P<0.01).The findings suggest that some envir-onmental pollutants existing in the electronic waste(e-waste)dismantling region may affect the health of local parturient women and newborns,representing changes both in serum levels of thyroid hormones and in mRNA expression of its receptors.

关键词： electronic waste thyroid hormones hormone receptor puerperant infant newborn

Feasibility of a novel vermitechnology using vermicast as substrate for activated sludge disposal by two epigeic earthworm species

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Agricultural Sciences 2013年第10期4卷 529-535页

作者： Kui Huang Fusheng Li Xiaoyong Fu xuemin chen Graduate School of Engineering Gifu University Gifu Japan River Basin Research Center Gifu University Gifu Japan School of Environmental and Municipal Engineering Lanzhou Jiaotong University Lanzhou China

This study was conducted to investigate the feasibility of vermicomposting by using vermicast as the substrate for the stabilization of municipal activated sludge, called hereafter as direct vermistabilization, in which the pre-treatment and bulking materials required in previous practices were all omitted. For this purpose, two epigeic earthworm species, namely Eisenia foetida and Bimastus parvus, were inoculated into substrate for composting fresh dewatered activated sludge. Direct vermistabilization resulted in significant reductions in pH, TOC, C/N ratio and the content of heavy metals, as well as increases in EC, total N, total P and total K in the final vermicast. Moreover, both Eisenia foetida and Bimastus parvus showed faster growth rate and higher cocoon production. The results of this study suggest that the direct vermistabilization has the advantages of being simple, cost-effective and efficient, and can thus be used as a feasible vermicomposting approach to convert fresh dewatered activated sludge into a valuable product for agricultural use. The results also suggest that Bimastus parvus can be used as a new potential candidate for vermicomposting of municipal activated sludge.

关键词： Activated Sludge Biology Earthworms Heavy Metals Nutrients Vermicomposting

Clinical Application of Primary Suture Following Three-Port Laparoscopic Common Bile Duct Exploration: A Report of 176 Cases

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Surgical Science 2015年第1期6卷 1-6页

作者： Shengze Li Huihua Cai Donglin Sun xuemin chen Shengyong Liu Xinquan Wu Yong An Jing chen Chun Yang Yaping Sun Xiaoyan Lu Department of General Surgery The Third People’s Hospital of Jiangyin Wuxi China Department of Hepatobiliary Surgery The First People’s Hospital of Changzhou The 3th Hospital Affiliated to Soochow University Suzhou China

Objective: To investigate the feasibility, safety and the clinical value of primary suture following 3-port laparoscopic common bile duct exploration (LCBDE). Methods: From January 2012 to September 2014, 176 patients suffered from choledocholithiasis were treated with primary suture following 3-port LCBDE and the clinical data were retrospectively analyzed. Results: All cases were operated successfully and none was converted to open surgery. The duration of operation was 92.2 ± 18.8 min and the length of postoperative hospital stay was 4.4 ± 3.7 d. Postoperative bile leakage occurred in 2 cases and these patients recovered by simple drainage for 3 to 7 days without re-operation. All patients recovered smoothly without any serious complications. Conclusions: Primary suture following 3-port LCBDE is safe, effective and mini-invasive, which is worthy of further clinical application.

关键词： Laparoscopy Common Bile Duct Exploration Primary Suture Three-Port