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Oscillating Propagation of Kink in Nondissipative Frenkel-Kontorova Chain Due to External DC Force

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Communications in Theoretical Physics 2009年第4期51卷 765-767页

作者： ZENG Shang-You TANG Yi ren Xi-mei ZHAO De-Jiang Department of Physics Xiangtan University Xiangtan 411105 China

We report the oscillating propagation of kink in a nondissipative Frenkel-Kontorova （FK） chain driven by external DC force, which is different from the usual propagation of localized modes with equal speed. When the kink moves in the opposite direction of the external DC force, the kink will be accelerated and the potential of the FK chain in the external force field is transformed to be the kinetic energy of the kink. If the kink reaches the boundary of the FK chain, the kink will be bounced back and moves in the opposite direction, then the kink will be decelerated gradually and the kinetic energy of the kink ＆ transformed to be the potential of the FK chain in the external force field. If the speed of the kink reaches zero, the kink will move in the opposite direction again driven by the external DC force, and a new oscillating cycle begins. Simulation result demonstrates exactly the transformation between the kinetic energy of the kink and the potential of the FK chain in the external force field. The interesting energy exchange is induced by the special topology of kinks, and other localized modes, such as breathers and envelope solitons, have no the interesting phenomenon.

关键词： kink nondissipative Frenkel Kontorova chain oscillating propagation external DC force

Microstructure and stability of SrCe_(0.9)Yb_(0.1)O_(3-α)ceramics in H_(2)/H_(2)O/CO_(2)supercritical environment

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Rare Metals 2023年第5期42卷 1460-1464页

作者： Jia-Chen Wang Wei-Jing Wang Yu-mei ren Qing-He Yu College of Bioscience and Resources Environment Beijing University of AgricultureBeijing102206China School of Materials Science and Engineering Northeastern UniversityShenyang110819China National Engineering Research Center of Nonferrous Metals Materials and Products for New Energy China GRINM Group Co.LtdBeijing100088China GRIMAT Engineering Institute Co. LtdBeijing101407China General Research Institute for Nonferrous Metals Beijing100088China Great Wall Motor Company Limited Hebei Automotive Technology Innovation CenterBaoding071000China

SrCe_(0.9)Yb_(0.1)O_(3-α)ceramic samples were obtained by dry pressing and sintering of powders prepared by solid reaction method.X-ray diffraction(XRD)and the field-emission scanning microscope(SEM)were used for phase and microstructure analysis of *** results showed that the ceramics sintered in the air were pure perovskite *** results revealed that the average grain size of ceramics increased from 2 to 10μm when the sinteringtemperature increased from 1400 to 1500℃.

关键词： ceramics ceramic Microstructure

RELATIVE SEA-LEVEL RISE IN YELLOW RIVER DELTA——IMPLICATIONS AND RESPONSE STRATEGIES

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Journal of Geographical Sciences 1991年第2期2卷 1-13页

作者： ren mei-e Cui Gonghao Department of Geo.and Ocean Science Nanjing University

The Holocene Yellow River Delta,with an area of 250,000km2,is one of the largest deltas in the *** paper focuses on its coastal plain,including three younger deltas,*** delta near Tianjin,the modern delta,and the abandoned *** the first two deltas,land subsidence,both natural and man-induced,is serious,and local sea-level rise is mainly a result of land *** major direct impacts of relative sea-level rise on the Yellow River Delta are submergence and salinity *** a great part of the three younger deltas is less than 2m asl,with 1m being a result of sea-level rise,the danger of submergence is great,especially during the storm ***-lying coastal plain will increasingly suffer from salt water intrusion and drainage will be *** action is urgently required to avert or mitigate adverse effects.

关键词： relative sea-level rise land subsidence Yellow River Delta risk assessment

Synthesis and NHE1 inhibitory activity of ligustrazine derivatives

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Chinese Chemical Letters 2007年第5期18卷 539-541页

作者： mei ren Yun Gen Xu Na Wen Da Yong Zhang Wei Yi Hua Center of Drug Discovery China Pharmaceutical University Nanjing 210009 China Department of Pharmacology China Pharmaceutical University Nanjing 210009 China

A series of novel derivatives of ligustrazine linked with substituted benzoyl guanidine were synthesized. These compounds have not been reported in literature, and their chemical structures were confirmed by IR, ^1H NMR and MS. The results of NHE1 inhibitory activity test showed that compounds I2, I3, I4, I6, and I7 possess more potent NHE1 inhibitory activity than cariporide.

关键词： Na^+/H^+ exchanger inhibitors Ligustrazine derivatives Benzoyl guanidine derivatives Synthesis

Characterization of surface EMG signals using improved approximate entropy

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第10期7卷 844-848页

作者： CHEN Wei-ting WANG Zhi-zhong ren Xiao-mei Department of Biomedical Engineering Shanghai Jiao Tong University Shanghai 200240 China

An improved approximate entropy (ApEn) is presented and applied to characterize surface electromyography (sEMG) signals. In most previous experiments using nonlinear dynamic analysis, this certain processing was often confronted with the problem of insufficient data points and noisy circumstances, which led to unsatisfactory results. Compared with fractal dimension as well as the standard ApEn, the improved ApEn can extract information underlying sEMG signals more efficiently and accu- rately. The method introduced here can also be applied to other medium-sized and noisy physiological signals.

关键词： Surface EMG (sEMG) signal Nonlinear analysis Approximate entropy (ApEn) Fractal dimension

Time-delay Positive Feedback Control for Nonlinear Time-delay Systems with Neural Network Compensation

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自动化学报 2008年第9期34卷 1196-1202页

作者： NA Jing ren Xue-mei HUANG Hong Department of Automatic Control School of Information Science and Technology Beijlng Institute of Technology Beijing 100081 P. R. China

新适应时间延期积极反馈控制器(ATPFC ) 为非线性的时间延期系统的一个班被介绍。建议控制计划由神经基于网络的鉴定和时间延期组成积极反馈控制器。与一个特殊动态鉴定模型一起合并的二个高顺序的神经网络(HONN ) 被采用识别非线性的... 详细信息

新适应时间延期积极反馈控制器(ATPFC ) 为非线性的时间延期系统的一个班被介绍。建议控制计划由神经基于网络的鉴定和时间延期组成积极反馈控制器。与一个特殊动态鉴定模型一起合并的二个高顺序的神经网络(HONN ) 被采用识别非线性的系统。基于识别模型，本地 linearization 赔偿被用来处理系统的未知非线性。线性化的系统的一个 time-delay-free 逆模型和一个需要的引用模型被利用组成反馈控制器，它能导致系统输出追踪一个引用模型的轨道。为鉴定和靠近环的控制系统的追踪的错误的严密稳定性分析借助于 Lyapunov 稳定性标准被提供。模拟结果被包括表明建议计划的有效性。

关键词：正反馈控制系统自动化系统人工神经网络

Revealing High-Efficiency Natural Mycotoxin Antidotes in Zebrafish Model Screening Against Zearalenone-Induced Toxicity

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Engineering 2024年第11期42卷 196-212页

作者： Hong-Yun Zhang Wei-Dan Jiang Pei Wu Yang Liu Hong-mei ren Xiao-Wan Jin Xiao-Qiu Zhou Lin Feng Animal Nutrition Institute Sichuan Agricultural UniversityChengdu 611130China Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province Sichuan Agricultural UniversityChengdu 611130China Key Laboratory of Animal Disease-Resistant Nutrition(Ministry of Education of the People’s Republic of China) Sichuan Agricultural UniversityChengdu 611130China Key Laboratory of Animal Disease-Resistance Nutrition and Feed(Ministry of Agriculture and Rural Affairs of the People’s Republic of China) Sichuan Agricultural UniversityChengdu 611130China

Zearalenone(ZEA),a mycotoxin,poses a significant global hazard to human and animal *** products(NPs)have shown promise for mitigating the adverse effects of ZEA owing to their diverse func-tional ***,the current challenge lies in the absence of an efficient strategy for systematic screening and identification of NPs that can effectively protect against ZEA-induced *** study describes a phenotype-based screening strategy for screening NP libraries and discovering more effective compounds to mitigate or counteract the adverse consequences of ZEA exposure in *** this strategy,we initially identified 96 NPs and evaluated the potency and efficacy of two effective candidate compounds,fraxetin,and hydroxytyrosol,based on embryonic phenotype and locomotor activity using a scoring system and the TCMacro ***,we performed transcriptome and proteinprotein interaction(PPI)network analyses to extract two mRNA signatures to query the Connectivity Map(CMap)database and predict *** predicted NPs showed the potential to reverse the gene expression profiles associated with ZEA ***,we further screened these compounds using our model,which indicated that hispidin,daphnetin,and riboflavin exhibit promising in vivo effi-cacy in ***,throughout the process,fraxetin consistently stood out as the most promising *** pathway analysis and functional verification revealed that fraxetin completely reversed the toxic effects of ZEA at very low *** was achieved by repairing damaged cell apoptosis,modifying the cell cycle pathway,and preventing senescence induction,indicating good application ***,we demonstrated that this integration strategy can be successfully applied to effectively discover potential antidotes.

关键词： Zearalenone Natural products Phenotype-based screening Transcriptome analysis Fraxetin

Microbial Activity in a Temperate Forest Soil as Affected by Elevated Atmospheric CO_2

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Pedosphere 2010年第4期20卷 427-435页

作者： ZHENG Jun-Qiang HAN Shi-Jie ZHOU Yu-mei ren Fei-Rong XIN Li-Hua ZHANG Yan Forestry Center Institute of Applied Ecology Chinese Academy of Sciences 72 Wenhua Road Shenyang 110016 （China）

Microorganisms play a key role in the response of soil ecosystems to the rising atmospheric carbon dioxide （CO2） as they mineralize organic matter and drive nutrient cycling. To assess the effects of elevated CO2 on soil microbial C and N immobilization and on soil enzyme activities, in years 8 （2006） and 9 （2007） of an open-top chamber experiment that begun in spring of 1999, soil was sampled in summer, and microbial biomass and enzyme activity related to the carbon （C）, nitrogen （N） and phosphorus （P） cycling were measured. Although no effects on microbial biomass C were detected, changes in microbial biomass N and metabolic activity involving C, N and P were observed under elevated CO2. Invertase and .dehydrogenase activities were significantly enhanced by different degrees of elevated CO2. Nitrifying enzyme activity was significantly （P 〈 0.01） increased in the August 2006 samples that received the elevated COs treatment, as compared to the samples that received the ambient treatment. Denitrifying enzyme activity was significantly （P 〈 0.04） decreased by elevated COs treatments in the August 2006 and June 2007 （P 〈 0.09） samples, β-N-acetylglucosaminidase activity was increased under elevated CO2 by 7% and 25% in June and August 2006, respectively, compared to those under ambient CO2. The results of June 2006 samples showed that acid phosphatase activity was significantly enhanced under elevated CO2. Overall, these results suggested that elevated CO2 might cause changes in the belowground C, N and P cycling in temperate forest soils.

关键词： CO2 enrichment microbial biomass soil carbon cycling soil nitrogen cycling

EXPERIMENTAL STUDY ON BED-LOAD SEDIMENT TRANSPORT IN IRREGULAR WAVE-CURrenT COEXISTENT FIELD

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Journal of Hydrodynamics 2000年第2期12卷 42-53页

作者： Wu, Yongsheng Qin, Chongren Hu, mei Tianjin Univ Tianjin China

In order to evaluate bed-load sediment transport in an irregular wave-current coexistent field, a series of experiments were completed in laboratory with an irregularly oscillating tray, which is designed to simulate the irregular wave-current coexistent field. The initial motion of sediment and the rates of transport over flat horizontal bed were tested. Comparison between experimental results of initial motion and modified Shields curve indicates that the Shields curve is still valid for the case of irregular wave-current coexistent field. Analysis of flow regime shows that initial conditions fall within smooth-turbulent transitional region. The results of transport rate show that net sediment transport rate can be expressed approximately as the function of the maximum bottom shear stress and mean shear stress. A dimensionless formula is proposed on the basis of the mechanisms of waves erode sediments and tides transport sediments.

关键词： Flow of water Ocean currents Oscillations Shear stress Water waves