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SYNTHESIS OF POLY(GLUTAMIC ACID-co-ASPARTIC ACID) VIA COMBINATION OF N-CARBOXYANHYDRIDE RING OPENING POLYMERIZATION WITH DEBENZYLATION

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Chinese Journal of Polymer Science 2013年第12期31卷 1706-1716页

作者： Wei-xi Yang ling-ling Wang Han zhu Ri-wei Xu 吴一弦 State Key Laboratory of Chemical Resource Key Laboratory of Carbon Fiber and Functional Polymers(Ministry of Education)Beijing University of Chemical Technology

The random copolymers of glutamic acid （LG） and aspartic acid （ASP）, poly（LG-co-ASP）, with designed compositions could be successfully synthesized via combination of N-carboxyanhydride ring opening copolymerization with debenzylation. Ring opening copolymerizations of y：benzyl-L-glutamate N-carboxyanhydride （BLG-NCA） and β-benzyl-Laspartate N-carboxyanhydride （BLA-NCA） were carried out by using different amines including triethylamine （TEA）, diethylamine, n-hexylamine （NHA）, triphenylamine, diphenylamine or aniline as initiators. All the 6 amines were highly efficient to get well-defined poly（BLG-co-BLA） copolymers with designed compositions although the polymerizations proceeded via different mechanisms （normal amine mechanism or/and activated monomer mechanism）, which are based on chemical structure of amines. The molecular weights of poly（BLG-co-BLA） copolymers could be mediated by both TEA concentration and polymerization time. Then, debenzylation ofpoly（BLG-co-BLA） copolymers was conducted to prepare the corresponding hydrophilic random eopolymers of poly（LG-co-ASP） with a-subunit structure in ASP structural units. The contents of LG structural units in poly（LG-co-ASP） copolymers matched with those of BLG-NCA in NCA-monomer feeds in ring opening copolymerizations initiated by NHA or TEA and were closed to the theoretical line. The diblock copolymer of poly（BLG-b-BLA） could also be synthesized via living NCA ring opening copolymerization by sequential addition of BLG- NCA and BLA-NCA.

关键词： Peptide Ring opening polymerization Copolymer Glutamic acid Aspartic acid.

Impacts of Food and Energy Price Hikes and Proposed Coping Strategies

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China & World Economy 2008年第6期16卷 35-45页

作者： ling zhu Deputy Director and Senior Fellow Institute of Economics Chinese Academy of Social Sciences Beijing China

Based on sample survey data for the years 2006 and 2007, we find that inflation of food and energy prices in China is moving at a slower pace than in the international market; however, the livelihood of low income groups has been significantly impacted. Urban sample households in low income groups have been shifting from consumption of high value food to lower value substitutes; and all of the rural sample households are reducing their total consumption expenditure in real terms. The Engel＇ s coefficient of the rural household enlarged while their proportion of spending on clothing and energy declined. Farmers＇ households are moving toward more imbalanced diets, and the nutritional status of the poor is apparently deteriorating. The emergency-response measures that the government should implement include stopping subsidies to biofuel producers, who use foodstuffs as inputs, and providing food aid to the poor. The mid-term strategies should include anti-monopoly tactics, improving the market environment for the right competition, and eliminating price distortion. Midterm and long-term socioeconomic policy reform must be undertaken to adjust the social structure, to correct the mechanism of factor price formation, and to transform the pattern of economic growth.

关键词： food energy coping strategies

Old Age Security: A Case from Rural Suzhou

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China & World Economy 2006年第2期14卷 67-78页

作者： ling zhu Senior Fellow Institute of Economics Chinese Academy of Social Sciences Beijing China.

During the course of urbanization and industrialization, a growing number of farmers have become landless as local governments have bought out their land for non-agricultural uses. Even in the localities where the industrialization process absorbs a vast majority of rural labor, the questions of how to compensate for the economic shock on the rural landless and how to alleviate and eliminate mental suffering as a result of losing land have always been a challenge to government capacity in social stabilization and a yardstick to measure social justice in local communities. In the administration areas of Suzhou City in Jiangsu Province, governments at all levels have successfully coped with this challenge. By means of ＂swapping land for old-age support＂ and income redistribution, Suzhou municipality has not only met the demand on land for urbanization and industrialization while maintaining social stability, but also laid a foundation for establishing an integrated pension system for both urban and rural residents. Such a system has changed the tradition of farmers＇ households relying on land to deal with economic risk and of the aged depending on their sons for livelihood support in rural society.

关键词： community services land acquisition pension insurance

Effective-Field Theory for Kinetic Ising Model on Honeycomb Lattice

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Communications in Theoretical Physics 2009年第5期51卷 927-930页

作者： SHI Xiao-ling WEI Guo-zhu College of Sciences Liaoning University of Petroleum and Chemical Technology Fushun 113001 China College of Sciences Northeastern University Shenyang 110004 China International Center for Material Physics Academia Sinica Shenyang 110015 China

As an analytical method, the effective-field theory （EFT） is used to study the dynamical response of the kinetic Ising model in the presence of a sinusoidal oscillating field. The effective-field equations of motion of the average magnetization are given for the honeycomb lattice （Z = 3）. The Liapunov exponent A is calculated for discussing the stability of the magnetization and it is used to determine the phase boundary. In the field amplitude ho / ZJ-temperature T/ZJ plane, the phase boundary separating the dynamic ordered and the disordered phase has been drawn. In contrast to previous analytical results that predicted a tricritical point separating a dynamic phase boundary line of continuous and discontinuous transitions, we find that the transition is always continuous. There is inconsistency between our results and previous analytical results, because they do not introduce sufficiently strong fluctuations.

关键词： kinetic Ising model effective-field theory phase transition

p-JNK/p-c-Jun通路参与大鼠杏仁核点燃癫痫模型

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神经损伤与功能重建 2016年第6期11卷 473-475页

作者：李巷潘建青康慧聪杨志刚韩金玲聂荔肖小华张玲玲朱遂强深圳市南山区人民医院神经内科广东深圳518052 华中科技大学同济医学院附属同济医院神经内科武汉430030 深圳市第二人民医院广东深圳518052

目的:研究杏仁核点燃癫痫模型中c-Jun氨基末端激酶(JNK)通路的活化。方法:雄性Wistar大鼠20只,随机分为对照组10只和模型组10只。将电极植入大鼠右侧杏仁核,对照组不给予电刺激,模型组每天给予500μA的电流刺激,大鼠连续10 d在刺激后达... 详细信息

目的:研究杏仁核点燃癫痫模型中c-Jun氨基末端激酶(JNK)通路的活化。方法:雄性Wistar大鼠20只,随机分为对照组10只和模型组10只。将电极植入大鼠右侧杏仁核,对照组不给予电刺激,模型组每天给予500μA的电流刺激,大鼠连续10 d在刺激后达到5级发作视为点燃成功。成功点燃的大鼠,在最后1次5级发作后2 h处死。Western blot检测2组海马JNK、p-JNK、c-Jun、p-c-Jun的表达。结果:模型组刺激侧海马p-JNK、p-c-Jun表达明显高于对照组(P<0.05)。结论:p-JNK/p-c-Jun通路可能参与杏仁核癫痫模型点燃。

关键词：杏仁核点燃磷酸化JNK 磷酸化c-Jun

Mean-Field Studies of a Mixed Spin-3/2 and Spin-2 and a Mixed Spin-3/2 and Spin-5/2 Ising System with Different Anisotropies

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Communications in Theoretical Physics 2009年第4期51卷 756-760页

作者： WEI Guo-zhu MIAO Hai-ling College of Sciences Northeastern University Shenyang 110004 China International Center for Material Physics Academia Sinica Shenyang 110015 China

The magnetic properties of a mixed spin-3/2 and spin-2 and a mixed spin-3/2 and spin-5/2 Ising ferromag- netic system with different anisotropies are studied by means of mean-field theory （MFT）. The dependence of the phase diagram on single-ion anisotropy strengths is studied too. In the mixed spin-3/2 and spin-2 Ising model, besides the second-order phase transition, the first order-disorder phase transition and the tricritical line are found. In the mixed spin-3/2 and spin-5/2 Ising model, there is no first-order transition and trieritical line.

关键词： mixed spin Ising system mean-field theory phase transition

Stabilizing surface chemistry and texture of single-crystal Ni-rich cathodes for Li-ion batteries

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Journal of Materials Science & Technology 2022年第30期125卷 192-197页

作者： Zhaofeng Yang ling Chen Huawei zhu Yihua zhu Hao Jiang Chunzhong Li Shanghai Engineering Research Center of Hierarchical Nanomaterials School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China Key Laboratory for Ultrafine Materials of Ministry of Education Frontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China

The single-crystalline Ni-rich cathodes are believed to help improve the safety of Li-ion batteries(LIBs),however,the ion-diffusion limits their high-rate performance owing to large single-crystal ***,a dual-modification strategy of surface Li_(2)TiO_(3)-coating and bulk Ti-doping has been performed to achieve high-rate single crystal LiNi_(0.83)Co_(0.12)Mn_(0.05)O_(2)(NCM)*** Li-ion conductive Li_(2)TiO_(3) coating layer facilitates the Li-ion transfer and prevents the electrolyte ***,the robust Ti-O bonds stabilize the cubic close-packed oxygen framework and mitigate the Li/Ni *** synergy endows the dual-modified NCM with enhanced de-/lithiation reaction kinetics and stable surface chemistry.A high specific capacity of 128 mAh g^(-1) is delivered even at 10 C with an extended cycle *** finding is reckoned to pave the way for developing high energy density LIBs for long-range electric vehicles.

关键词： NCM811 Single-crystal Dual-modification Specific capacity Li-ion batteries

North Carolina’s forest disturbance and timber production assessed using time series Landsat observations

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International Journal of Digital Earth 2015年第12期8卷 947-969页

作者： Chengquan Huang Pui-Yu ling Zhiliang zhu Department of Geographical Sciences University of MarylandCollege ParkMDUSA U.S.Geological Survey RestonVAUSA

Wood products provide a relatively long-term carbon storage *** to lack of consistent datasets on these products,however,it is difficult to determine their carbon *** main purpose of this study was to quantify forest disturbance and timber product output(TPO)using time series Landsat observations for North *** results revealed that North Carolina had an average forest disturbance rate of 178,000 ha per year from 1985 to *** derived disturbance products were found to be highly correlated with TPO survey data,explaining up to 87%of the total variance of county level industrial roundwood *** level TPO estimates derived using the Landsat-based disturbance products tracked those derived from ground-based survey data *** TPO modeling approach developed in this study complements the ground-based TPO surveys conducted by the US Forest *** allows derivation of TPO estimates for the years that did not have TPO survey data,and may be applicable in other regions or countries where at least some ground-based survey data on timber production are available for model development and dense time series Landsat observations exist for developing annual forest disturbance products.

关键词： timber products output remote sensing vegetation change tracker

Large eddy simulation of water flow over series of dunes

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Water Science and Engineering 2011年第4期4卷 421-430页

作者： Jun LU ling-ling WANG Hai zhu Hui-chao DAI College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 P. R. China Zhangjiagang Water Conservancy Bureau Zhangjiagang 215600 P. R. China

Large eddy simulation was used to investigate the spatial development of open channel flow over a series of dunes. The three-dimensional filtered Navier-Stokes （N-S） equations were numerically solved with the fractional-step method in sigma coordinates. The subgrid-scale turbulent stress was modeled with a dynamic coherent eddy viscosity model proposed by the authors The computed velocity profiles are in good agreement with the available experimental results. The mean velocity and the turbulent Reynolds stress affected by a series of dune-shaped structures were compared and analyzed. The variation of turbulence statistics along the flow direction affected by the wavy bottom roughness has been studied. The turbulent boundary layer in a complex geographic environment can be simulated well with the proposed large eddy simulation （LES） model.

关键词： large eddy simulation (LES) dunes turbulent boundary layer flow separation