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Journal of Iron and Steel Research International 2014年第7期21卷 637-643页

作者： Dian-hua ZHANG Jian-zhao cao Jiu-jing XU Wen PENG De-wen ZHAO State Key Laboratory of Rolling and Automation Northeastern University

The weighted velocity field was simplified for analysis of hot strip rolling. Using the field and GM （geometric midline） yield criterion, the deformation power, friction power and shear power were obtained respectively. Summing the partial power contributions, the total deformation power for strip rolling was presented. Then, by minimizing the power function, the rolling force was obtained; meanwhile, considering the effect of roll elastic flattening, iterative calculation of the roll radius was carried out until the radius was convergent. On line data were corn pared with the calculated results to verify the model accuracy. It was indicated that the calculated rolling forces were basically in agreement with the measured ones since the maximum error was less than 10.0%. Moreover, the effects of various rolling conditions such as thickness reduction, friction factor and shape factor, upon separating force, location of neutral angle, and stress state coefficient were discussed systematically.

关键词： hot strip rolling rolling force simplified weighted velocity field GM yield criterion elastic flattening analytical solution

Brownfield Redevelopment Toward Sustainable Urban Land Use in China

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Chinese Geographical Science 2007年第2期17卷 127-134页

作者： cao Kang GUAN hua School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China

Brownfield redevelopment is a new urban land use strategy to pursue the ideal of sustainable development. It relieves environmental pressure and resolves the glaring contradiction between urban land idleness and urban sprawl. It addresses issues of urban land use and farmland protection in China. This paper compares brownfield with greenfield, and defines brownfield and its redevelopment. It elaborates general and special government policies for this sustainable land use strategy in the context of China. General policies contain two aspects: clarifying brownfield redevelopment's priority in Chinese urban planning and land use and setting a general quantitative redevelopment target. The extent of the government's special policies, which aim at coordinating three factors in the redevelopment process, namely govern- ments, developers and users, are divided into five areas: statistics and categorization, assessment and remediation, fi- nancial supports and tax incentives, environmental and legal liability, and publicity and guidance. The paper concludes the major functions of different levels of Chinese government in the redevelopment process, i.e. making general strategy, formulating legislation, spectifying regulations and technical standards, estimating and categorizing brownfield sites, drawing up brownfield planning, providing information and financial support, guiding developers, publicizing the strategy to the public, and checking reuse results.

关键词： brownfield redevelopment sustainable development land use

Generation of chimeric monkeys using embryonic stem cells

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Zoological Research 2023年第6期44卷 1154-1155页

作者： jing cao Zhen Liu Institute of Neuroscience CAS Center for Excellence in Brain Science and Intelligence TechnologyCAS Key Laboratory of Primate NeurobiologyState Key Laboratory of NeuroscienceChinese Academy of SciencesShanghai 200031China

Embryonic stem cells(ESCs)represent a subtype of pluripotent stem cells(PSCs)derived from the inner cell mass of *** cells exhibit three principal features:the capacity for unlimited self-replication,the ability to differentiate into diverse somatic cell types in vitro,and the potential to contribute to chimera animals in vivo upon reintroduction into the host ***,ESCs are widely used in basic and biomedical research,as well as in applications such as cell replacement therapy and the creation of genetically modified animal models.

关键词： stem creation diverse

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唐山市植被覆盖度时空演变及地形因子的响应

华北理工大学学报（自然科学版） 2025年第1期47卷 88-95页

作者：曹琳吴风华华北理工大学矿业工程学院河北唐山063210

植被覆盖度在生态环境质量评价、地表过程监测和生态保护决策等方面发挥着重要作用。研究基于GEE平台,采用像元二分法获取唐山市不同时段的植被覆盖度。通过Sen趋势分析和MK检验探讨植被覆盖度的时空演变情况。利用GIS叠加分析研究植被... 详细信息

植被覆盖度在生态环境质量评价、地表过程监测和生态保护决策等方面发挥着重要作用。研究基于GEE平台,采用像元二分法获取唐山市不同时段的植被覆盖度。通过Sen趋势分析和MK检验探讨植被覆盖度的时空演变情况。利用GIS叠加分析研究植被覆盖度与地形因子的关系。结果表明:(1)唐山市植被覆盖度稳定,城市建设区域和南部沿海地区较低,中部和北部低山区较高,中等级及以上占比超过65%。(2)在2001~2021年间,唐山市的植被覆盖度轻微改善,改善面积达到了39.041%。(3)植被覆盖度与高程和坡度显著相关,特别在高程200米以上和坡度15°~32°范围内,中高等级和高等级植被覆盖度较高。探究植被覆盖度演变对该地区的生态环境改善具有重要意义。

关键词：植被覆盖度时空演化地形因子

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A VERTICAL 2-D NUMERICAL SIMULATION OF SUSPENDED SEDIMENT TRANSPORT

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Journal of Hydrodynamics 2007年第2期19卷 217-224页

作者： ZHANG jing-xin LIU hua Department Of Engineering Mechanics Shanghai Jiaotong University Shanghai 200240 China

Numerical simulation of sediment transport and bed evolution has become an important technique in the sediment research. In this article, a numerical model of suspended sediment transport was proposed, which was established in the vertical σ coordinate for fitting the free surface and bottom. In the research of the sediment transport, the predominant factors were found to be the eddy diffusion, the settling velocity, the bed condition and so on. By the aid of the model in the article, the contribution of the Rouse parameter to the vertical profile of sediment concentration was clarified, which was identical to the theoretical results. In the comparison of the numerical results with laboratory data, the agreement between experimental data and numerical results was reached except for some data. And the possible reasons for the disagreement were discussed.

关键词： suspended sediment transport 2-D numericalmodel σ coordinate

Recent progress in porous Mg-based foam preparation approaches:effect of processing parameters on structure and mechanical property

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Journal of Iron and Steel Research International 2022年第3期29卷 371-402页

作者： Solomon-Oshioke Agbedor Dong-hui Yang jing cao Jian-qing Chen Bassiouny Saleh Chao Qiu Lei Wang jing-hua Jiang Ai-bin Ma College of Mechanics and Materials Hohai UniversityNanjing211100JiangsuChina Suqian Research Institute of Hohai University Suqian223814JiangsuChina Ocean and Offshore Engineering Research Institute of Hohai University Nantong226019JiangsuChina

Porous metals are a class of cellular materials with lightweight and unique mechanical,electrical,thermal,physical and acoustic *** and magnesium alloy foams have exhibited excellent *** particular,open-cell Mg-based foams(porous Mg/Mg alloy foams)have been used for bioresorbable implants,CO_(2)trapping systems,filters,heat exchangers,absorbent panels and many other *** significant progress has been taken in producing porous Mg-based foams with good structure-property relations,but with a large number of different processing parameters,different mechanical properties and pore morphologies of each porous Mg-based foam,it is essential to understand the individual effects of each aspect of the ***,the present article summarized the effects of available processing parameters on the structure and mechanical properties of the porous Mg-based ***,the future perspectives to enhance the structure and properties of porous Mg/Mg alloy foams were discussed.

关键词： Porous Mg alloy Powder processing Sintering Liquid metal infiltration Mechanical property

Corrosion Behavior of Epoxy-Coated Rebar with Pinhole Defect in Seawater Concrete

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Acta Metallurgica Sinica(English Letters) 2018年第11期31卷 1171-1182页

作者： Yao-Zong Mao Ying-hua Wei Hong-Tao Zhao Chen-Xi Lv Hai-Jiao cao jing Li School of Materials Science and Engineering University of Science and Technology of China Institute of Metal Research Chinese Academy of Sciences

Experiments were carried out to investigate the corrosion behavior of epoxy-coated rebar （ECR） with pinhole defect（diameter in hundreds of microns） immersed in the uncarbonated/carbonated simulated pore solution （SPS） of seawaterconcrete. Corrosion behavior was analyzed by electrochemical impedance spectroscopy. The composition and morphologyof corrosion products were characterized by X-ray diffraction, energy-dispersive spectrometry and scanning electronmicroscopy. Meanwhile, oxide film produced by preheating before spray coating was investigated by X-ray photoelectronspectroscopy and Mott-Schottky technology. Results indicated that corrosion behavior of ECR with pinhole defectexhibited three stages when immersed in the uncarbonated/carbonated SPS. In the initial stage, steel in defect waspassivated when exposed in the uncarbonated SPS and corroded when exposed in the carbonated SPS, due to competitiveadsorption between chloride and hydroxyl ions. In the second stage, the oxide film under coating reconstituted （thethickness and defects density decreasing） in the uncarbonated SPS, which was caused by the synergy between highhydroxide and chloride activity, while in the carbonated SPS, crevice corrosion happened under the coating around pinhole,because of the different oxygen concentrations cell at the coating/steel interface. In the third stage, localized corrosionoccurred under the coating around the pinhole in the uncarbonated SPS, which was probably induced by ion diffusion at thenano-scale coating/steel interface. The corrosion products adjacent to the defects were re-oxidized from FeCIa.4HaO andFe2（OH）3Cl to Fe2O3.H2O, and the corrosion area was expanded outward in the carbonated SPS.

关键词： Corrosion Epoxy-coated rebar (ECR) Seawater concrete Pinhole defects

S空位及非金属掺杂单层Bi_(2)S_(2)Se的第一性原理研究

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原子与分子物理学报 2025年第1期42卷 127-134页

作者：张建华王敏陈畅曹倩徐银湖北大学资源环境学院武汉430062

Bi_(2)S_(2)Se是一种新兴的具有优异光电性能的材料,因此受到了广泛的关注.本研究采用第一性原理方法和开源程序,研究了本征单层Bi_(2)S_(2)Se以及掺杂非金属元素X(X=P,Cl,Br和I)和S空位的体系的电子结构和光学特性.计算结果表明,改性... 详细信息

Bi_(2)S_(2)Se是一种新兴的具有优异光电性能的材料,因此受到了广泛的关注.本研究采用第一性原理方法和开源程序,研究了本征单层Bi_(2)S_(2)Se以及掺杂非金属元素X(X=P,Cl,Br和I)和S空位的体系的电子结构和光学特性.计算结果表明,改性后出现了晶格缺陷.含S空位和P、Cl、Br掺杂体系的带隙减少,而I掺杂体系的带隙增加.同时,含S空位和Cl、Br、I掺杂体系的费米能级穿过导带底,而P掺杂体系的费米能级穿过价带顶.所有改性体系在费米能级附近都出现了缺陷能级或杂质能级,表现出较高的可见光吸收能力和散射能力,改性体系的对可见光的吸收能力和散射能力有所增加.

关键词： Bi_(2)S_(2)Se 掺杂电子结构光学性质第一性原理

Dechlorination mechanism of 2,4-dichlorophenol by Ni/Fe nanoparticles in the presence of humic acid

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第1期10卷 121-126页

作者： jing-jing WO Zhen ZHANG Xin-hua XU Department of Environmental Engineering Zhejiang University Hangzhou 310027 China School of Bioscience Taizhou University Linhai 317000 China

To understand the feasibility of its application to the in situ remediation of contaminated groundwater,the dechlori-nation of 2,4-dichlorophenol (2,4-DCP) by Ni/Fe nanoparticles in the presence of humic acid (HA) was *** found that,as high performance liquid chromatography (HPLC) was used,the 2,4-DCP was first quickly reduced to o-chlorophenol (o-CP) and p-chlorophenol (p-CP),and then reduced to phenol as the final *** experimental results indicated that HA had an adverse effect on the dechlorination of 2,4-DCP by Ni/Fe nanoparticles,as the HA concentration increased,the removal rate decreased *** also demonstrated that 2,4-DCP was reduced more easily to o-CP than to p-CP,and that the sequence of the tendency in dechlorination of intermediates was p-CP>*** electron microscope (TEM) showed that HA could act as an adsorbate to compete reactive sites on the surface of Ni/Fe nanoparticles to decrease the dechlorination *** we con-cluded that the dechlorination reaction of 2,4-DCP over Ni/Fe nanoparticles progressed through catalytic reductive dechlorination.

关键词： Dechlorination Ni/Fe nanoparticles 2 4-dichlorophenol (2 4-DCP) Humic acid (HA)

Direct oxidative C(sp^3)-H cyanation of secondary benzylic ethers

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Chinese Chemical Letters 2019年第6期30卷 1241-1243页

作者： Zehua Wang Ying Mao Honghao Guan Min cao jing hua Lei Feng Lei Liu School of Chemistry and Chemical Engineering Shandong University Ji'nan 250100 China School of Pharmaceutical Sciences Shandong University Ji'nan 250012 China State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical Sciences of Guangxi Normal University Guilin 541004 China

Current studies on the oxidative C--H functionalization of benzylic ethers for C--C forging process dominantly focus on primary ethers. The corresponding reaction of secondary ethers remains underdeveloped. Herein, a practical and efficient oxidative C--H cyanation of secondary benzylic ethers with TMSCN in the presence of DDQ is described. The metal-free process is well tolerated with a wide variety of electronically varied α-monosubstituted isochromans, facilely furnishing a library of isochromans bearing α-aryl α-cyano substituent patterns for further diversification and bioactive small molecule identification.

关键词： C-H functionalization Cyanation Oxidation Secondary ether Tertiary ether synthesis