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Well-Deformed Oblate K Isomers Induced by Oblate Intruder States

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Chinese Physics Letters 2001年第6期18卷 750-752页

作者： xu fu-Rong Department of Technical Physics Peking UniversityBeijing 100871 MOE Key Laboratory Institute of Heavy Ion PhysicsPeking UniversityBeijing 100871 Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100080

With configuration-constrained potential energy surfaces,it has been found that the neutron-deficient Z≈82 nuclei can have well-deformed oblate K isomers which are formed by exciting quasiparticles to the proton i_(13/2) and h_(9/2) oblate intruder *** achieve the configuration constrained calculations,the maximum-overlap method of wavefunctions is *** the present calculations of quasiparticle states,quadrupole pairings are *** observed K^(π)=11^(-) isomer in 188Pb is confirmed to be oblately deformed,with energy consistent with the *** low-lying oblate isomeric states are predicted for ^(187)Tl.

关键词： deformed constrained quasi

PICARD ITERATION FOR NONSMOOTH EQUATIONS

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Journal of Computational Mathematics 2001年第6期19卷 583-590页

作者： Song-bai Sheng Hui-fu xu College of Science Nanjing University of Aeronautics and AstronauticsNanjing 210016China Australian Graduate School of Management the University of New South WalesSydneyAustralia

Presents an analysis of the generalized Newton method, approximate Newton methods, and splitting methods for solving nonsmooth equations from Picard iteration viewpoint. Details of the radius of the weak Jacobian of P... 详细信息

关键词： nonsmooth equations picard iteration weak Jacobian convergence

SYNTHESIS OF A SILICON-CONTAINING FLAME RETARDANT AND ITS SYNERGISTIC EFFECT WITH POTASSIUM-4-(PHENYLSULFONYL)BENZENESULFONATE(KSS) IN POLYCARBONATE(PC)

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Chinese Journal of Polymer Science 2013年第10期31卷 1352-1358页

作者： Dan-dan Yuan xu-fu Cai Department of Polymer Science and Materials State Key Laboratory of Polymer Materials Engineering Sichuan University

A novel flame retardant （DAPSiO）, containing silicon and nitrogen, was synthesized by using dichlorodiphenylsilane, γchloropropyl methyl dimethoxysilane and 1,2-ethanediamine. DAPSiO was used together with potassium-4-（phenylsulfonyl）benzenesulfonate （KSS） to prepare a flame-retardant system for polycarbonate （PC）. The structure of DAPSiO was characterized by Fourier transform infrared spectroscopy （FTIR）, and 1H-NMR tests. Flammability and thermal behaviors of PC/KSS/DAPSiO systems were estimated by limited oxygen index （LOI）, vertical burning test （UL-94） and thermogravimetric analysis （TGA） tests. The results showed that the flame retardancy and thermal stability of PC/KSS system were improved with the addition of DAPSiO. When 1 wt% DAPSiO and 0.5 wt% KSS were incorporated, the LOI value of PC was found to be 44, and class V-0 of UL-94 test was passed. The scanning electron microscopy （SEM） and FTIR indicated that PC/KSS/DAPSiO system held a more cohesive and denser char structure when compared with pure PC and PC/KSS system.

关键词： Flame retardant Thermal properties Silicon Polycarbonate.

EXPONENTIAL CONVERGENCE OF SAMPLE AVERAGE APPROXIMATION METHODS FOR A CLASS OF STOCHASTIC MATHEMATICAL PROGRAMS WITH COMPLEMENTARITY CONSTRAINTS

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Journal of Computational Mathematics 2006年第6期24卷 733-748页

作者： Fan-wen Meng Hui-fu xu The Logistics Institute - Asia Pacific National University of Singapore 1 Law Link Singapore School of Mathematics University of Southampton Highfield Southampton S017 1B J UK School of Mathematics University of Southampton Highfield Southampton S017 1B J UK

In this paper, we propose a Sample Average Approximation （SAA） method for a class of Stochastic Mathematical Programs with Complementarity Constraints （SMPCC） recently considered by Birbil, G/irkan and Listes [3]. We study the statistical properties of obtained SAA estimators. In particular we show that under moderate conditions a sequence of weak stationary points of SAA programs converge to a weak stationary point of the true problem with probability approaching one at exponential rate as the sample size tends to infinity. To implement the SAA method more efficiently, we incorporate the method with some techniques such as Scholtes＇ regularization method and the well known smoothing NCP method. Some preliminary numerical results are reported.

关键词： Stochastic mathematical programs with complementarity constraints Sampleaverage approximation Weak stationary points Exponential convergence.

Conceptual understandings of the ecological engineering issues in China and abroad

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Journal of Environmental Sciences 2000年第2期12卷 78-83页

作者： xu, fu-Liu Tao, Shu Departemnt of Urban and Environemmal Sciences Peking University Beijing 100871 China

The research on ecological engineering has been lasting for more than four decades. As a new, cheaper, environmentally acceptable and alternative techniques, ecological engineering has been applied to many aspects, including ecoagricultural engineering, ecosystem restoration, environmental conservation, and pollution control. This paper presents a conceptual understanding on the issues of ecological engineering, including its origin, concepts, goals, principles and applications.

关键词： ecological engineering ecologist engineer CLC number: X171 4 Document code: A

In-situ evaluation for corrosion process at fusion boundary of stainless steel strip overlay joints in H2S containing solution

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 413-419页

作者： ZOU Yang PAN Chun-xu fu Qiang Department of Physics & Center for Electron Microscopy Wuhan University Wuhan 430063 China Department of Physics & Center for Electron Microscopy Wuhan University Wuhan 430063 China Department of Physics & Center for Nano-Science and Technology Wuhan University Wuhan 430063 China

The present work studied the corrosion properties around the fusion boundaries of 2.25Cr-1Mo steel with stainless steel strip overlay joints under as welded condition and after post-weld heat treatment (PWHT) in H2 S containing solution (NACE TM-01-77 standard) with different time. An in-situ observation method was introduced for evaluating corrosive progress in the fusion boundary in H2 S containing solution, that is, the samples were marked firstly at the boundary and then treated in the solution for variant time. Each time after the corrosion treatment, the observations were kept to focus at the same marked area by using scanning electron microscopy (SEM) to observe the corrosion progress. The results reveal that the fusion boundary is the worst region for corrosion resistance when comparing with other boundaries, and a broad fusion boundary has a stronger resistance for "hydrogen induced disbonding" than a narrow one.

关键词： dissimilar steel welding fusion boundary H2S corrosion post-weld heat treatment

An Improved Method to Prepare FePO4 by Introduction of Na3PO4 and Its Usage for Fabricating LiFePO4

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Journal of Wuhan University of Technology(Materials Science) 2019年第5期34卷 1097-1102页

作者： SI Xiurong LI Min fu xu Civil Engineering Department North China Institute of Aerospace EngineeringLangfang 065000China Hebei ANZ New Energy Tech.Co. Ltd.Langfang 065000China

A LiFePO4/C composite was synthesized by a simple solid-state reaction method using glucose as reductive agent and carbon source and FePO4 as precursor, which was prepared by introduction of Na3PO4 as phosphorus source and pH regulator in order to pursue lower cost and environmental protection. The structure and morphology of FePO4 and LiFePO4/C were investigated by X-ray diffraction(XRD) and scanning electron microscopy(SEM). furthermore, electrochemical performance of LiFePO4/C was investigated by galvanostatic charge–discharge tests and cyclicvoltammogram(CV). The results indicate that FePO4 obtained has a small particle size and uniform particle distribution, which is demonstrated to be applicable as the iron source to synthesize LiFePO4/C. Prepared LiFePO4/C shows an excellent rate capability and cycle performance. At rates of 0.1 C, 0.2 C, 1 C and 2 C, the initial discharge capacities of 161, 158, 145 and 120 mAh/g were achieved, respectively and the discharge capacity is 154, 153, 140 and 116 mAh/g after 400 cycles. The employed method of preparing FePO4 by introduction of Na3PO4 has advantages such as low cost, safe raw material, environmental benign and recyclable products, which is suitable for industrial production.

关键词： lithium ion batteries cathode LiFePO4 FePO4

Endoscopic polypectomy: A promising therapeutic choice for esophageal carcinosarcoma

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World Journal of Gastroenterology 2009年第27期15卷 3448-3450页

作者： Feng Ji Yue-Mei xu Cheng-fu xu Department of Gastroenterology the First Affiliated Hospital College of Medicine Zhejiang University Hangzhou 310003 Zhejiang Province China

Esophageal carcinosarcoma is a rare malignant tumor composing of both carcinomatous and sarcomatous elements. Endoscopic therapy is less invasive and may represent an alternative to esophagectomy for superf icial esophageal carcinosarcoma. Here, we report a 61-year-old male who was diagnosed as esophageal carcinosarcoma and underwent endoscopic polypectomy with well tolerance and favorable prognosis. We also present a brief review of the literature.

关键词： Carcinosarcoma Endoscopic polypectomy Endoscopic ultrasonography

Simulation of wind-driven circulation and temperature in the near-shore region of southern Lake Michigan by using a channelized model

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Journal of Hydrodynamics 2013年第1期25卷 97-111页

作者： LIU Lubo fu xu-dong WANG Guang-qian Department of Civil and Geomatics Engineering Lyles College of Engineering California State University State Key Laboratory of Hydroscience and Engineering Tsinghua University

To enhance the efficiency of a pathogen forecasting model in the beach areas of southern Lake Michigan and to reduce the computation time, the near-shore current is approximated as a channelized flow parallel to the shorelines in clockwise or anti-clock- wise direction within the accuracy tolerance range. A channelized model with a curvilinear boundary can significantly reduce the computation effort, and at the same time achieve a good agreement between the predicted and measured water surface elevations, currents, and water temperatures. The sensitivity analysis results show that the suitable channel width for the near-shore region of southern Lake Michigan should be no less than 10 kin. The modeling results of the water temperature are much less sensitive to the channel width than those of the current velocity and the water surface elevation. The modeling results also show a close correlation between the speeds of the wind and the near-shore current. The current may fully respond the wind stress with a time lag of several hours. The correlation may provide an approximate estimation of the lake circulation under some wind conditions for a practical fore- casting purpose. More complex wind-current relationships need to be described with a more sophisticated hydrodynamic model. This verified model can be used for the pathogen forecasting in the near-shore regions of southern Lake Michigan in the future.

关键词： near-shore channelized wind hydrodynamic model