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Fractional Smoothness of Some Stochastic Integrals

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Acta Mathematica Sinica,English Series 2007年第6期23卷 1053-1058页

作者： Peng xie Xi cheng ZHANG Department of Mathematics Huazhong University of Science and Technology Wuhan 430074 P. R. China

We study the fractional smoothness in the sense of Malliavin calculus of stochastic integrals of the form ∫0^1Ф（Xs）dXs, where Xs is a semimartingale and Ф belongs to some fractional Sobolev space over R.

关键词： fractional Sobolev space stochastic integral interpolation

The thinnest high-temperature superconductor

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National Science Review 2014年第3期1卷 324-325页

作者： Xin-cheng xie School of Physics Peking University

Superconductivity is one of the most important topics in physics and materials *** superconducting transition temperature(T C)of a quasi-2D superconductor,a superconductor with one dimension smaller than the coherence length of Cooper pairs,is normally descending with decreasing sample thickness since thermal and quantum luctuations are expected to destroy the superconducting phase coherence even at low *** question of how thin

关键词： STO high UC The thinnest high-temperature superconductor SQUID

Preface： Centennial Physics at Peking University

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Frontiers of physics 2013年第5期8卷 473-474页

作者： Xin-cheng xie School of Physics Peking University Beijing 100871 China

The Year 2013 is probably as much remarkable for the development of modern physical science in China as it is for School of Physics at Peking University. One hundred years ago, the physics division was born in Peking University, as the very first physics higher education unit having appeared in modern national universities of China. Ill tile first one hundred years, the School has made distinguished contributions to the nation and to the world in both education and academia. As we celebrate the birthday of its first century and set our sights on the next, it is my great pleasure to invite you to this special issue of Frontier of Physics on ＂Centennial Physics at Peking University＂. In 1913, the ＂WuLi Men＂（Physics Division） was established at Peking University, and was later renamed the Department of Physics in 1919. With the reorganization of the Chinese system of higher education in 1952, the new Physics Department of Peking University was created from the merger of the physics departments of Peking University, Tsinghua University and Yenching University. This became the premier center for physics in China. The School of Physics was established in 2001, and includes not only the traditional fields of study in physics, but also related physical sciences. Throughout its history, the School has educated and hosted many prominent physicists, including figures such as Ta-You Wu, C. N. Yang, T. D. Lee, and Kun Huang. Today, the School of Physics includes Physics, Astronomy, Atmospheric ＆： Oceanic Sciences, and Nuclear Science ~： Technology. Research is devoted not only to tile frontiers of fundamental physics but also to the innovation of advanced technology. Major research fields include high energy physics, astroptwsics and cosmology, radioactive nuclear physics, high energy-density physics, key technologies for advanced light sources and particle beams, the interaction of particle beams with materials, mesoscopic semiconductor light emission and laser physics, ultr

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Analysis of Effect of Gas Temperature on Cooling Stave of Blast Furnace

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Journal of Iron and Steel Research International 2010年第1期17卷 1-6页

作者： xie Ning-qiang cheng Shu-sen School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

In order to study the effect of gas temperature variation on cooling stave, temperature, stress and displacement distributions of cooling stave were analyzed respectively when gas temperature inside- blast furnace increases from 1000 to 1 600 ℃. The results show that the temperature field on cold side is under control of cooling pipes and hardly changes when gas temperature increases. The temperature gradient and change rate with time near hot sides are greater than those in other regions and the later can reach 100 ℃/s. The stress intensity near middle area of hot surface is up to 400 MPa and that＇s why there are lots of cracks at this place. The edge of stave is bent to cold side and middle regions between fixed bolts and pin moves to hot side. The displacement around fixed pin is smaller but larger on the edge and the maximum is located on hot side of top surface. The maximum displacement in z direction is about 4 mm and 3 mm in y direction. If the expansion coefficient of packing layer is 1/4, the thickness of packing layer between the cooling staves is 32 mm and 24 mm between sides up and down.

关键词： temperature variation displacement temperature change rate stress intensity packing layer

Hydrogen generation from polyvinyl alcohol-contaminated wastewater by a process of supercritical water gasification

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Journal of Environmental Sciences 2007年第12期19卷 1424-1429页

作者： YAN Bo WEI Chao-hai HU cheng-sheng xie cheng WU Jun-zhang College of Environmental Science and Engineering South China University of Technology Guangdong 510640 China

Gasification of polyvinyl alcohol （PVA）-contaminated wastewater in supercritical water （SCW） was investigated in a continuous flow reactor at 723-873 K, 20-36 MPa and residence time of 20-450 s. The gas and liquid products were analyzed by GC/TCD, and TOC analyzer. The main gas products were H2, CH4, CO and CO2. Pressure change had no significant influence on gasification efficiency. Higher temperature and longer residence time enhanced gasification efficiency, and lower temperature favored the production of H2. The effects of KOH catalyst on gas product composition were studied, and gasification efficiency were analyzed. The TOC removal efficiency （RTOC）, carbon gasification ratio （RCG） and hydrogen gasification ratio （RHG） were up to 96.00%, 95.92% and 126.40% at 873 K and 60 s, respectively, which suggests PVA can be completely gasified in SCW. The results indicate supercritical water gasification for hydrogen generation is a promising process for the treatment ofPVA wastewater.

关键词： hydrogen generation supercritical water gasification polyvinyl alcohol wastewater

Transport patterns and numerical simulation of heavy metal pollutants in soils of lead–zinc ore mines

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Journal of Mountain Science 2021年第9期18卷 2345-2356页

作者： CAO Jie xie cheng-yu HOU Zhi-ru College of Environment and Resources Xiangtan UniversityXiangtan 411105China School of Metallurgy and Environment Central South UniversityChangsha 410083China

Exploring transport patterns of soil contaminants is essential for solving the problem of heavy metal contamination in mine *** this study,contamination of Pb,Zn,and Cd in the mountain soils of the lead–zinc ore mines in Ganxi Township,Hengdong County,Hunan Province,China was investigated,and their transport patterns were further explored using a soil-column model and numerical simulation *** total,111 mine soil samples were collected and placed into six experimental soil *** controlling the water flow,a control soil column group(CK),two mixed soil columns X1 with daily water flows of 1 and 5 L,and three mixed soil columns X3 with daily water flows of 2,3,and 4 L were *** results showed that the residual fraction of Pb accounted for 71.93%of the content on average,whereas the exchangeable fractions of Zn,Cd,and Fe-Mn oxide-bound fractions of Zn and Cd accounted for 28.60%,31.07%,and 43.2%and 53.54%of the content,***,Zn,and Cd in the soils of the CK,X1,and X3 groups mainly were accumulated at a depth from approximately 0 to 20 cm,and the content at this depth accounted for 60.09%of that at a 0~40 cm *** soil at a depth range of 0~10 cm was most seriously contaminated,and the proportion of content was 32.39%of that at a 0~40 cm *** simulation showed that on the 5 th day,the pollutant transport range was 0~24 cm,and on the 9 th day,the pollutant transport range exceeded 40 *** the 15 th day,the transport capacity of pollutants at depths of 0~40 cm was close to the stable state,but the soil at a depth of 0~10 cm was still heavily *** results reflect the transport pattern of heavy metal pollutants in the soil of lead–zinc ore mines and may provide a reliable scientific support for the prevention of heavy metal contamination in mine environments.

关键词： Mountain Mine soil Heavy metals Numerical simulations Pollutants Transport patterns

Microstructure and mechanical properties of Ti/Al/Ti clad plates prepared via powder-in-tube method

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Journal of Iron and Steel Research International 2024年第3期31卷 670-687页

作者： Xian-lei Hu Qin-cheng xie Yi Yuan Ying Zhi State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina Suzhou Dongbao Haixing Metal Material Technology Co. Ltd.Suzhou 215600JiangsuChina School of Material Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina

The Ti/Al/Ti clad plates exhibit a broad spectrum of potential ***,the conventional techniques of hot-pressing composite and explosive composite are intricate and environmentally hazardous.A novel method was introduced for preparing clad plates,namely,the powder-in-tube *** method involves a combination of cold rolling,annealing at a temperature of 550℃,and double *** morphology of the intermetallic compound layer was analyzed through the utilization of interface stripping test,tensile test,and microscopic *** interface morphology,interface bonding properties,tensile fracture structures,and properties of plates under the first and second rolling were compared,along with the effects of intermetallic compounds on the interface *** results indicate that the powder-in-tube method,when annealed at 550℃,can produce a composite plate featuring a complete and uniform Ti/Al *** obtained plate exhibits a peeling strength of 21.5 N/mm,tensile strength of 424 MPa,and elongation of 11.5%.Furthermore,a systematic analysis was conducted to determine the causes of performance degra-dation observed during annealing at temperatures of 600 and 650℃.

关键词： Powder-in-tube method-Ti/Al/Ti clad plate Annealing Cold rolling-Mechanical property

Recent advances in condensed-matter physics in China

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National Science Review 2017年第2期4卷 153-154页

作者： Xin-cheng xie Lu Yu School of Physics Peking University NSR Institute of Physics Chinese Academy of Sciences

Over the past decade,research in condensed-matter physics in China has progressed *** and more outstanding physicists from China are gaining global recognition with cutting-edge research *** capture a glimpse of the

关键词： In more Recent advances in condensed-matter physics in China PKU

Apolipoprotein E gene polymorphism and susceptibility to intracerebral hemorrhage:A meta-analysis

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Neural Regeneration Research 2009年第1期4卷 58-61页

作者： Bo Peng Weifu Chen Zongyi xie Yuan cheng Department of Neurosurgery Second Affiliated Hospital of Chongqing Medical University Chongqing 400010 China

OBJECTIVE： To evaluate the relationship between apolipoprotein E （ApoE） gene polymorphism and susceptibility to intracerebral hemorrhage （ICH） in Chinese population by a meta-analysis. METHODS： Related literature regarding control analysis between ICH and control groups was collected. Independent case-control studies published between 1989 and 2007 that had complete data were included; and articles not closely related to the topic were excluded. The meta-analysis software, RevMan 4.2, was applied to analyze the odds ratio （OR） value in those studies included in the analysis to assess the relationship between susceptibility to ICH and ApoE polymorphism. RESULTS： Eight papers which were in accordance with the inclusion criteria were selected, and a total of 1 249 ICH cases and 1 329 controls were involved. Meta-analysis results showed that with the wildtype E3/3 as a reference, the OR values （95% confidence interval） of intracerebral hemorrhage for subjects carrying E2/2, E3/2, E4/2, E4/3, and E4/4 were 1.15 （0.60–2.21）, 1.00 （0.79–1.28）, 3.01 （1.73–5.23）, 1.78 （1.41–2.24） and 1.94 （1.03–3.65）, respectively. The combined OR values （95% confidence interval） of intracerebral hemorrhage for ε4 and ε2 carriers were 1.53 （1.16–2.01）, and 0.93 （0.69–1.25）. CONCLUSION： The results suggest that ApoE polymorphism is significantly associated with susceptibility to intracerebral hemorrhage and that ε4 carriers have a higher risk for intracerebral hemorrhage than others.

关键词： apolipoprotein E intracerebral hemorrhage gene polymorphism Meta-analysis