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Transfer kinetics of phenol between aqueous phase and N,N-di(1-methy.-hepty.) acetamide in kerosene

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Journal of Environmental Sciences 2000年第2期12卷 19-23页

作者： Zhu-xian, y. Hui-fang, D. Qi-hong, Z. Zu-ming, Z. Dept. of Environmental Sci./Eng. Fudan University Shanghai 200433 China

The transfer kinetics of phenol between aqueous phase and N,N di(methy. hepty.) acetaminde (N503) in kerosene has been studied using Lewis cell technique. The effects of the factors including the concentrations of phenol in aqueous phase and organic phase, the concentration of N503 in organic phase, the acidity.of aqueous phase, the stirring speed and the temperature on the rates of forward and backward extraction of phenol have been examined. The regularity.of extraction rate has been obtained. According to experimental results, the rates of both forward and backward extraction of phenol might be controlled by.diffusion process. The diffusion step of phenol from aqueous phase to interface for forward extraction and from interface to aqueous phase for backward extraction might be the rate controlling steps.

关键词： phenol transfer kinetics N,N di(1 methy. hepty.) acetamide CLC number: X703 Document code: A Introduction

Effects of Magnetic Field on Charge—Ordering Transitions in La2CuO4.08 and Pr0.5Sr0.5Mno3

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Chinese Phy.ics Letters 2003年第5期20卷 738-741页

作者： LIJian-Qi CHENLing y.Hong-Chun y.Matsui ZHAOZhong-xian InstituteofPhy.icsandCondensedMatterPhy.ics ChineseAcademyofSciencesBeijing100080 NationalInstituteforResearchinInorganicMaterials 1-1NamikiTsukubaIbaraki305Japan

The applied magnetic field can result in evident changes on the charge-ordering transitions in both Cu-based high Tc superconductors and Mn-based colossal magnetioresistance materials. Alternations of charge modulation and melting of well-defined charge stripes can be commonly.observed when the magnetic field is over 2 T. We herein present the experimental data obtained in LaCuO4.08 and Pr0.5Sr0.5MnO3 materials, illustrating this kind of interesting phenomena at low temperatures. In particular, some essential structural features alternating along with charge-ordering transition have been discussed.

关键词： Manganese compounds

A novel adaptive-impulsive sy.chronization of fractional-order chaotic sy.tems

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Chinese Phy.ics B 2015年第10期24卷 86-92页

作者： Leung y.T.Andrew Li xian-Feng Chu y.n-Dong Zhang Hui Department of Architecture and Civil Engineering City University of Hong Kong School of Mathematics and Phy.ics Lanzhou Jiaotong University School of Mechatronic Engineering Lanzhou Jiaotong University

A novel adaptive-impulsive scheme is proposed for sy.chronizing fractional-order chaotic sy.tems without the necessity.of knowing the attractors＇ bounds in priori. The nonlinear functions in these sy.tems are supposed to satisfy.local Lipschitz conditions but which are estimated with adaptive laws. The novelty.is that the combination of adaptive control and impulsive control offers a control strategy.gathering the advantages of both. In order to guarantee the convergence is no less than an expected exponential rate, a combined feedback strength design is created such that the sy.metric axis can shift freely.according to the updated transient feedback strength. All of the unknown Lipschitz constants are also updated exponentially.in the meantime of achieving sy.chronization. Two different fractional-order chaotic sy.tems are employ.d to demonstrate the effectiveness of the novel adaptive-impulsive control scheme.

关键词： adaptive-impulsive sy.chronization fractional order chaotic sy.tems combined feedbackstrength

Sy.metry.and Period-Adding Windows in a Modified Optical Injection Semiconductor Laser Model

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Chinese Phy.ics Letters 2012年第1期29卷 1-4页

作者： LI xian-Feng Andrew y.T.Leung CHU y.n-Dong Department of Mathematics Lanzhou Jiaotong UniversityLanzhou 730070 Department of Civil and Architectural Engineering City University of Hong KongHong Kong

Hierarchical structural sy.metry.of periodic islands embedded in the chaotic region of modified optical injection semiconductor lasers(MOISLs)is expounded upon in phase *** onset of the bifurcation cascade shows remarkable accumulation *** cascade follows a specific period-adding ***-similarities and infinite spiral nestings shrinking bey.nd a certain point of the periodic hub are revealed to affirm the existence of self-organized distribution of periodicity.and chaos in phase diagrams.

关键词： periodic bifurcation sy.metry

An iterative blending integrating grinding force model considering grain size and dislocation density.evolution

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Advances in Manufacturing 2023年第3期11卷 428-443页

作者： Zi-Shan Ding y.n-Hui Zhao Miao-xian Guo Wei-Cheng Guo Chong-Jun Wu Steven y.Liang School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai 200093People's Republicof China College of Mechanical Engineering Donghua UniversityShanghai 201620People's Republic of China George W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlanta 30332USA

The dy.amic force load in grinding process is considered as a crucial factor affecting the quality.of parts,and a better understanding of the mechanism of force generation is conducive to revealing the evolution of material microstructure more *** this study.an iterative blending integrating grinding force model that comprehensively.considers the impact of grain size and dislocation density.evolution of the material is *** to the grinding kinematics,the interaction of grit-workpiece is divided into rubbing,plowing,and chip formation stages in each grinding *** this basis,the evolution of material microstructure in the current chip formation stage will affect the rubbing force in the next grinding arc through flow stresses,which in turn will influence the total grinding ***,the flow stress models in rubbing and chip formation stages are firstly.established,and then the dislocation density.prediction model is established experimentally.based on the characteristics of grain *** effects of the evolution of grain size and dislocation density.on the grinding forces during the grinding process are studied by.means of iterative *** results indicate that the implementation of an iterative blending scheme is instrumental in obtaining a higher accurate prediction of the grinding force and a deeper insight of the influence mechanisms of materials microstructure on grinding process.

关键词： Grinding force Grain size Dislocation density Iterative loop

Mechanisms for flowering plants to benefit arthropod natural enemies of insect pests： Prospects for enhanced use in agriculture

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Insect Science 2014年第1期21卷 1-12页

作者： Zhong-xian Lu Ping-y.ng Zhu Geoff M. Gurr Xu-Song Zheng Donna M. y. Read Kong-Luen Heong y.-Jun y.ng Hong-Xing Xu State Key.Laboratory.Breeding Base for Zhejiang Sustainable Pest and Disease Control Institute of Plant Protection and Microbiology Zhejiang Academy of Agricultural Sciences Hangzhou China EH Graham Centre for Agricultural Innovation Charles Stuff University Orange NSW Australia College of Chemistry.and Life Science Zhejiang Normal University Jinhua Zhejiang Province China and Crop and Environmental Sciences Division International Rice Research Institute Los Banos Metro Manila Philippines

Reduction of noncrop habitats, intensive use of pesticides and high levels of disturbance associated with intensive crop production simplify.the farming landscape and bring about a sharp decline of biodiversity. This, in turn, weakens the biological control ecosy.tem service provided by.arthropod natural enemies. Strategic use of flowering plants to enhance plant biodiversity.in a well-targeted manner can provide natural enemies with food sources and shelter to improve biological control and reduce dependence on chemical pesticides. This article reviews the nutritional value of various ty.es of plant-derived food for natural enemies, possible adverse effects on pest management, and the practical application of flowering plants in orchards, vegetables and field crops, agricultural sy.tems where most research has taken place. Prospects for more effective use of flowering plants to maximize biological control of insect pests in agroecosy.tem are good but depend up on selection of optimal plant species based on information on the ecological mechanisms by.which natural enemies are selectively.favored over pest species.

关键词： conservation biological control ecological engineering habitat nectar,nutrition pollen shelter

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虚拟水贸易在我国粮食安全问题中的应用

水科学进展 2006年第1期17卷 102-107页

作者：马静汪党献 A. y. Hoekstra 夏海霞中国水利水电科学研究院水资源研究所北京100044 UNESCO-IHE Institute for Water Education 2601 DA Delft The Netherlands 中国水利报社北京100053

借助虚拟水的概念，分析以粮食为载体的虚拟水国际、区际流量关系，以勾勒我国虚拟水贸易的基本格局。通过对未来我国在不同粮食发展战略下的粮食供需情况，确定我国粮食进口基本规模，对未来我国虚拟水贸易格局进行展望。分析结果表明... 详细信息

借助虚拟水的概念，分析以粮食为载体的虚拟水国际、区际流量关系，以勾勒我国虚拟水贸易的基本格局。通过对未来我国在不同粮食发展战略下的粮食供需情况，确定我国粮食进口基本规模，对未来我国虚拟水贸易格局进行展望。分析结果表明，1999年我国北方通过粮食贸易向南方地区输出的虚拟水量达到184亿m^3。我国北方地区以有限的水资源在支持其他区域发展、确保国家粮食安全方面发挥了不可替代的作用。未来30年中国将面临新增粮食需求1．4亿～2．0亿t的巨大压力，在保持较高自给水平的前提下，我国虚拟水贸易的格局不会发生重大变化。外流域调水工程是保障国家粮食安全，维护社会稳定，促进可持续发展和造福中国人民的重大举措。虚拟水战略可作为跨流域调水的补充，在保障缺水地区水安全方面发挥重要作用。

关键词：虚拟水粮食安全区域贸易

Confined Cry.tallization Behaviors of Cross-linked Comb-like Copoly.ers

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Chinese Journal of Poly.er Science 2016年第8期34卷 1039-1046页

作者： xian-jing Gong 施德安 y.ng-kui y.ng Tao Jiang y.n-feng Meng Robert K.y.Li 蒋世春 School of Materials Science andEngineering Tianjin UniversityTianjin 300072China Ministry.of Education Key.Laboratory.for the Green Preparation and Application of Functional Materials Hubei Collaborative Innovation Center for Advanced Origanic Chemical MaterialsFaculty of Materials Science and EngineeringHubei UniversityWuhan 430062China School of Chemistry.and Materials Science Ludong UniversityYantai 264025China Department of Phy.ics and Materials Science City University of Hong KongHong KongChina

Cross-linked PEG-based copoly.ers were obtained via sy.thesis of poly.thy.ene gly.ol （PEG） and methoxy.poly.thy.ene gly.ol （MPEG） by.the bridging and/or cross-linking agent of 2,4-toly.ene diisocy.nate （TDI） and/or hexamethy.ene-l,6-diisocy.nate homopoly.er （HDI trimer）. The effects on the cry.tallization behaviors of the samples could be found with the changes in molecular weight of MC-PEG and molecular weight of SC-PEG in certain cross-linked density. It is revealed that the samples appear not to cry.tallize when the molecular weight of MC-PEG and SC-PEG are 1000 g/mol or less than that. The samples begin to cry.tallize when the molecular weight of either MC-PEG or SC-PEG reaches 2000 g/mol. The cry.tallinity.of cry.tallized MC-PEG decreases with the increasing molecular weight of uncry.tallized SC-PEG and the cry.tallinity.of cry.tallized SC-PEG declines with the rise of molecular weight of uncry.tallizable MC-PEG. The chains of SC-PEG （M_n = 2000 g/mol） can fold and align easilier than those of MC-PEG （M_n = 2000 g/mol）, when the content of PEG is the same.

关键词： PEG-based copoly.ers Cross-linking Comb-like Confined cry.tallization behavior.

Effects of Λ hy.erons on the deformations of even–even nuclei

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Chinese Phy.ics C 2022年第6期46卷 212-218页

作者： C.F.Chen Q.B.Chen xian-Rong Zhou y.y.Cheng Ji-Wei Cui H.-J.Schulze Department of Phy.ics East China Normal UniversityShanghai 200241China School of Phy.ics and Optoelectronic Engineering Xidian UniversityXi'an 710071China INFN Sezione di Catania Dipartimento di FisicaUniversitádi CataniaVia Santa Sofia 6495123 CataniaItaly

The deformations of multi-Λ hy.ernuclei corresponding to even-even core nuclei ranging from^(8)Be to^(40)Ca with 2,4,6,and 8 hy.erons are studied using the deformed Sky.me-Hartree-Fock *** is found that the deformations are reduced when adding 2 or 8 Λ hy.erons,but enhanced when adding 4 or 6 Λ *** differences are attributed to the fact that Λ hy.erons are filled gradually.into the three deformed p orbits,of which the [110] 1/2^(-)orbit is prolately.deformed and the degenerate [101]1/2^(-)and [101]3/2^(-)orbits are oblately.deformed.

关键词： deformation even-even nuclei effects of hy.eron(s)