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Degradation kinetics and products of triazophos in intertidal sediment

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Journal of Environmental Sciences 2005年第6期17卷 933-936页

作者： lin kun-de YUAN Dong-xing Institute of Environmental Science Zhejiang University Hangzhou 310029 China State Key Laboratory of Marine Environmental Science Environmental Science Research Center Xiamen University Xiamen 361005 China

This work presents taboratory studies on the degradation of triazophos in intertidat sediment. The overall degradations were found to follow the first-order decay model. After being incubated for 6 d, the percentage of degradations of triazophos in unsterilized and sterilized sediments were 94.5% and 20.5%, respectively. Between the temperatures of 15℃ and 35℃, the observed degradation rate constant（kob,d） enhanced as the incubation temperature increased. Triazophos in sediment degraded faster under aerobic condition than under anaerobic one. The water content of sediment had little influence on the degradation when it was in the range of 50%-100%. The values of kobsd decreased with increasing initial concentration of triazophos in sediment, which could result from the microorganism inhibition by triazophos. Four major degradation products, o, o-diethyl phosphorothioic acid, monoethyl phosphorothioic acid, phosphorothioic acid, and 1-phenyl-3-hydroxy-1, 2,4-triazole, were tentatively identified as their corresponding trimethylsilyl derivatives with a gas chromatography-mass spectrometer. The possible degradation pathway of triazophos in intertidal sediment was proposed. The results revealed that triazophos in intertidal sediment was relatively unstable and coutd be easily degraded.

关键词： triazophos degradation intertidal sediment

Neural stem cell activation and glial proliferation in the hippocampal CA3 region of posttraumatic epileptic rats

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Neural Regeneration Research 2011年第16期6卷 1232-1237页

作者： Yuanxiang lin kun lin Dezhi Kang Feng Wang Department of Neurosurgery First Affiliated Hospital of Fujian Medical University Fuzhou 350005 Fujian Province China

The present study observed the dynamic expression of CD133, nuclear factor-κB and glial fibrUlary acidic protein in the hippocampal CA3 area of the experimental posttraumatic epilepsy rats to investigate whether gliosis occurs after posttraumatic epilepsy. CD133 and nuclear factor-κB expression was increased at 1 day after posttraumatic epilepsy, peaked at 7 days, and gradually decreased up to 14 days, as seen by double-irnmunohistochemical staining. Glial fibrillary acidic protein/nuclear factor-EB double-labeled cells increased with time and peaked at 14 days after posttraumatic epilepsy. Results show that activation of hippocampal neural stem cells and glial proliferation after posttraumatic epilepsy-induced oxidative stress increases hippocampal glial cell density.

关键词： posttraumatic epilepsy neural stem cell glial cell CD133 nuclear factor-κB glialfibrillary acidic protein neural regeneration

Seismic AVO statistical inversion incorporating poroelasticity

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Petroleum Science 2020年第5期17卷 1237-1258页

作者： kun Li Xing-Yao Yin Zhao-Yun Zong Hai-kun lin School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071ShandongChina

Seismic amplitude variation with offset(AVO) inversion is an important approach for quantitative prediction of rock elasticity,lithology and fluid *** Biot-Gassmann's poroelasticity,an improved statistical AVO inversion approach is *** distinguish the influence of rock porosity and pore fluid modulus on AVO reflection coefficients,the AVO equation of reflection coefficients parameterized by porosity,rock-matrix moduli,density and fluid modulus is initially derived from Gassmann equation and critical porosity *** the analysis of the influences of model parameters on the proposed AVO equation,rock porosity has the greatest influences,followed by rock-matrix moduli and density,and fluid modulus has the least influences among these model ***,a statistical AVO stepwise inversion method is implemented to the simultaneous estimation of rock porosity,rock-matrix modulus,density and fluid ***,the Laplace probability model and differential evolution,Markov chain Monte Carlo algorithm is utilized for the stochastic simulation within Bayesian *** and field data examples demonstrate that the simultaneous optimizations of multiple Markov chains can achieve the efficient simulation of the posterior probability density distribution of model parameters,which is helpful for the uncertainty analysis of the inversion and sets a theoretical fundament for reservoir characterization and fluid discrimination.

关键词： Poroelasticity AVO inversion Statistical inversion Bayesian inference Seismic fluid discrimination

Microstructure and mechanical properties of WC-Co-based cemented carbide with bimodal WC grain size distribution

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Rare Metals 2023年第8期42卷 2809-2815页

作者： Rui-Jun Cao Chen-Guang lin Xing-Cheng Xie Zhong-kun lin Powder Metallurgy and Special Materials Department General Research Institute for Nonferrous MetalsBeijing 100088China

In order to improve the wear resistance of coarse-grained WC-Co cemented carbides,the fine WC powder were used to reinforce the metallic *** WC-Co-based cemented carbides having bimodal WC grain size distributions were synthesized by liquid phase *** comparison,the cemented carbides having unimodal WC grain size distributions were *** microstructure,hardness,fracture toughness and wear resistance of these cemented carbides were *** results show that adding fine WC powder is an effective method to improve the wear resistance of coarsegrained WC-Co cemented *** WC size,mean free path and fracture toughness decrease with the addition of fine WC powder,while the hardness exhibits an opposite *** impact-wear coefficient of bimodal distribution cemented carbides is noticeably lower than that of the unimodal one with the same hardness,which means that the cemented carbides with bimodal grain structure have better combination of hardness and impact-abrasive wear *** impact-abrasive wear mechanism of the bimodal cemented carbides is that the fine WC grains prevent abrasive wear and the coarse WC grains prevent impact wear.

关键词： WC-Co cemented carbide Impact wearing Bimodal distribution Hardness Mean free path

Asymptotic limit of the Gross-Pitaevskii equation with general initial data

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Science China Mathematics 2016年第6期59卷 1113-1126页

作者： LI FuCai lin Chi-kun WU kung-Chien Department of Mathematics Nanjing UniversityNanjing 210093 Department of Applied Mathematics and Center of Mathematical Modeling and Scientific Computing Chiao Tung UniversityHsinchu 30010 Department of Mathematics Cheng Kung UniversityTainan 70101

This paper mainly concerns the mathematical justification of the asymptotic limit of the GrossPitaevskii equation with general initial data in the natural energy space over the whole space. We give a rigorous proof of the convergence of the velocity fields defined through the solutions of the Gross-Pitaevskii equation to the strong solution of the incompressible Euler equations. Furthermore, we also obtain the rates of the convergence.

关键词： Gross-Pitaevskii equation asymptotic limit incompressible Euler equation general initial data

Research of Power Take-off System for “Sharp Eagle Ⅱ” Wave Energy Converter

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China Ocean Engineering 2019年第5期33卷 618-627页

作者： YE Yin WANG kun-lin YOU Ya-ge SHENG Song-wei Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Guangzhou 510640 China Key Laboratory of Renewable Energy Chinese Academy of Sciences Guangzhou 510640 China Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development Guangzhou 510640 China

The " Sharp Eagle” device is a wave energy converter of a hinged double floating body. The wave-absorbing floating body hinges on the semi-submerged floating body structure. Under the action of wave, the wave-absorbing floating body rotates around the hinge point, and the wave energy can be converted into kinetic energy. In this paper, the power take-off system of " Sharp Eagle Ⅱ” wave energy converter (the second generation of " Sharp Eagle”) was studied, which adopts the hydraulic type power take-off system. The 0-1 power generation mode was applied in this system to make the " Sharp Eagle Ⅱ” operate under various wave conditions. The principle of power generation was introduced in detail, and the power take-off system was simulated. Three groups of different movement period inputs were used to simulate three kinds of wave conditions, and the simulation results were obtained under three different working conditions. In addition, the prototype of " Sharp Eagle Ⅱ” wave energy converter was tested on land and in real sea conditions. The experimental data have been collected, and the experimental data and simulation results were compared and validated. This work has laid a foundation for the design and application of the following " Sharp Eagle” series of devices.

关键词： Sharp Eagle Wave Energy Converter power take-off power generation mode hydraulic system

Vascular resection in pancreatic adenocarcinoma with portal or superior mesenteric vein invasion

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World Journal of Gastroenterology 2013年第46期19卷 8740-8744页

作者： Gang Pan kun-lin Xie Hong Wu Department of Hepatobiliary Pancreatic Surgery West China Hospital Sichuan University

AIM:To evaluate long-term survival after the Whipple operation with superior mesenteric vein/portal vein resection(SMV/PVR)in relation to resection ***:We evaluated 118 patients who underwent the Whipple operation for pancreatic adenocarcinoma at our Department of Hepatobiliary Pancreatic Surgery between 2005 and ***-eight of these patients were diagnosed with microscopic PV/SMV invasion by frozen-section examination and underwent SMV/*** 28 patients,the length of SMV/PVR was≤3 *** the other 30 patients,the length of SMV/PVR was>*** and survival data were ***:SMV/PVR was performed successfully in *** was a significant difference between the two groups(SMV/PVR≤3 cm and SMV/PVR>3 cm)in terms of the mean survival time(18 mo vs 11 mo)and the overall 1-and 3-year survival rates(67.9%and14.3%vs 41.3%and 5.7%,P3 cm resection.

关键词： Pancreatic adenocarcinoma Whipple op-eration Vascular resection

Precoding with interference suppression sequence scheme for OFDM-based cognitive radio systems

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The Journal of China Universities of Posts and Telecommunications 2011年第4期18卷 59-64页

作者： ZHAO Cheng-lin ZHANG kun SUN Xue-bin JIANG Ting Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Orthogonal frequency division multiplexing （OFDM） is considered to be one of the promising schemes for cognitive radios （CR） systems, due to its flexibility in spectrum shaping. However, the traditional way of spectrum-notching failed to suppress out-of-band leakage enough, resulting in interference with licensed users （LUs）. A novel spectrum shaping scheme is proposed in this article, where a precoder with interference suppression sequence （ISS） is for the first time introduced for shaping the spectrum of OFDM signals in OFDM-based CR systems. The precoder matrix together with ISS matrix is obtained by minimizing the power of out-of-band interference, which results in the sufficient interference suppression of OFDM signal to LUs Analysis and simulation results show that the proposed scheme can significantly suppress the interference power to LUs at a little cost of precoding efficiency. Meanwhile, the peak-to-average-power-ratio （PAPR） is invariable and the bit-error-rate （BER） performance over Rayleigh fading channel is improved.

关键词： OFDM cognitive radio precoding spectrum shaping

Semi-empirical estimation for enhancing negative thermal expansion in PbTiO_(3)-based perovskites

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International Journal of Minerals,Metallurgy and Materials 2022年第4期29卷 783-786页

作者： Tao Yang Longlong Fan Yilin Wang kun lin Jun Chen Xianran Xing Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Solid State ChemistryDepartment of Physical ChemistryUniversity of Science and Technology BeijingBeijing 100083China College of Physics and Materials Science Tianjin Normal UniversityTianjin 300387China Institute of Advanced Materials Jiangsu National Synergetic Innovation Center for Advanced MaterialsNanjing Tech UniversityNanjing 211816China

Generally,most materials expand when heated and contract when cooled,whereas negative thermal expansion(NTE)materials are very *** a typical NTE material,PbTiO_(3) and related compounds have drawn particular interest in recent *** discovery of an enhanced NTE system in PbTiO_(3) is beneficial to deepen our understanding of its mechanism and regulate its *** present,the method of discriminating an enhanced NTE material based on PbTiO_(3) is not ***,we propose a semi-empirical method through evaluating the average lattice distortion in related systems to estimate the relative coefficient of thermal expansion *** rationality of the method was verified by the analysis of the 0.6PbTiO_(3)-0.4Bi(Ga_(x)Fe_(1-x))O_(3) *** far,all PbTiO_(3)-based compounds with enhanced NTE conform well to this *** method provides the possibility to find more enhanced NTE PbTiO_(3)-based materials.

关键词： enhanced negative thermal expansion crystal structure lead titanate spontaneous polarization