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Codimension 3 Non-resonant Bifurcations of Rough Heteroclinic Loops with One Orbit Flip

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Chinese Annals of mathematics,Series B 2006年第6期27卷 657-674页

作者： Shuliang SHUI deming zhu College of mathematics Physics and Information Engineering Zhejiaag Normal University Jinhua 321004 Zhejiang China College of Sciences Shanghai University Shanghai 200436 China department of mathematics East China Normal University Shanghai 200062 China

Heteroclinic bifurcations in four dimensional vector fields are investigated by setting up a local coordinates near a rough heteroclinic loop. This heteroclinic loop has a principal heteroclinic orbit and a non-principal heteroclinic orbit that takes orbit flip. The existence, nonexistence, coexistence and uniqueness of the 1-heteroclinic loop, 1-homoclinic orbit and l-periodic orbit are studied. The existence of the two-fold or three-fold 1-periodic orbit is also obtained.

关键词： Bifurcation Heteroclinic loop Non-resonance Orbit flip Periodic orbit

ELASTIC SCATTERING IN SKYRME MODEL

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Chinese Science Bulletin 1987年第3期32卷 152-157页

作者：朱伟沈建国郑繁安 department of Physics East China Normal University Shanghai Institute of Nuclear Research Academia Sinica Shanghai Institute of Nuclear Research Academia Sinica Shanghaihe idea that a baryon may be considered as a soliton in SU(2)×SU(2) chiral model has arrested much attention. There exist two distinct viewpoints on the chiral topological soliton model (called as skyrmion). One visualizes a skyrmion as an ideal model

The idea that a baryon may be considered as a soliton in SU(2)×SU(2) chiral model has arrested much attention. There exist two distinct viewpoints on the chiral topological soliton model (called as skyrmion). One vis... 详细信息

关键词： soliton topological chiral quark strange proton hadron excited deviation somewhat

千秋新学开南海百世名儒仰九江——晚清鸿儒朱次琦学术思想初探

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新乡师范高等专科学校学报 2004年第1期18卷 28-31页

作者：杨翔宇华东师范大学历史系上海200062

朱次琦作为晚清南海鸿儒，其学术思想博大精深。在晚清特定的历史条件下。其治学思想主要表现出尊宋斥汉、崇朱黜王、申实复孔、尊经重史的特点，这些特点均是围绕“经世致用”、“资治明道”这条主线而展开的，在当时的条件下，具有历... 详细信息

朱次琦作为晚清南海鸿儒，其学术思想博大精深。在晚清特定的历史条件下。其治学思想主要表现出尊宋斥汉、崇朱黜王、申实复孔、尊经重史的特点，这些特点均是围绕“经世致用”、“资治明道”这条主线而展开的，在当时的条件下，具有历史的进步性，但也有值得辨正之处。

关键词：朱次琦学术思想经世致用资治明道

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A JET MODEL

Chinese Science Bulletin 1982年第7期27卷 715-719页

作者：朱伟张民生沈建国 department of Physics East China Normal University Shanghai department of Physics Shanghai Teachers College Institute of Nuclear Research Academia Sinica Shanghaihe jet phenomenon has been discussed by many authors. In the usual treatment a set of quark fragmentation functions D_g~h(Z) are defined as a fundamental physical quantity describing the quark jet. It represents the probability of the hadrons of type "h" with momentum fraction Z per dz in quark jet.

The jet phenomenon has been discussed by many authors. In the usual treatment, a set of quark fragmentation functions D_g^h(Z) are defined as a fundamental physical quantity describing the quark jet. It represents the... 详细信息

关键词： quark fragmentation momentum hadron meson usual A JET MODEL introd describing transverse

Changes in albedo and its radiative forcing of grasslands in east Asia drylands

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Ecological Processes 2024年第1期13卷 237-251页

作者： Qingsong zhu Jiquan Chen Liangxu Wu Yuting Huang Changliang Shao Gang Dong Zhe Xu Xianglan Li State Key Laboratory of Remote Sensing Science College of Global Change and Earth System Science Faculty of Geographical ScienceBeijing Normal University department of Geography Environment and Spatial Sciences Michigan State University State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern china National Hulunber Grassland Ecosystem Observation and Research Station Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences School of Life Science Shanxi University

Background Grasslands in drylands are increasingly influenced by human activities and climate change, leading to alterations in albedo and radiative energy balance among others. Surface biophysical properties and their interactions change greatly following disturbances. However, our understanding of these processes and their climatic impacts remains limited. In this study, we used multi-year observations from satellites and eddy-covariance towers to investigate the response of albedo to variables closely associated with human disturbances, including vegetation greenness（EVI） and surface soil volumetric water content（VWC）, as well as snow cover and clearness index（Ta） for their potential *** EVI and VWC during the growing season were the primary factors influencing albedo. EVI and VWC were negatively correlated with albedo, with VWC's total direct and indirect impacts being slightly smaller than those of EVI. During the non-growing season, snow cover was the most influential factor on albedo. VWC and Ta negatively affected albedo throughout the year. We estimated the impact of variations in EVI and VWC on climate to be in the range of 0.004 to 0.113 kg CO2m-2yr-1in *** This study indicates the significant impacts of climate change and human disturbances on vulnerable grassland ecosystems from the perspective of altered albedo. Changes in vegetation greenness and soil properties induced by climate change and human activities may have a substantial impact on albedo, which in turn feedback on climate change, indicating that future climate policies should take this factor into consideration.

关键词： Albedo Global warming potential Grassland Disturbance

Stability and Uniqueness of Periodic Orbits Produced During Homoclinic Bifurcation

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Acta Mathematica Sinica,English Series 1995年第3期11卷 267-277页

作者： zhu deming department of mathematics east china normal university shanghai

Under a generic assumption, the existence and the uniqueness of the periodic orbit generating from a homoclinic bifurcation are shown, and the dimensions of its stable and unstable manifolds are given. In the case of ... 详细信息

关键词： Homoclinic bifurcation Periodic orbit Stable manifolds Dimensions

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双频率、双调谐电路原理及其应用

上海师范大学学报（自然科学版） 2003年第3期32卷 38-41页

作者：朱仁龙华东师范大学物理系上海200062

简要解释双频率、双调谐电路的工作原理,重点分析它的中和和隔离作用,除了作为金属探测电路以外,希望它能有更广泛地应用。

关键词：双频率双调谐中和隔离金属探测器

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不同饵料对中华绒螯蟹幼体发育和存活的影响

水产学报 2000年第5期24卷 442-447页

作者：江洪波陈立侨周忠良陈明朱钧华东师范大学生物系!上海200062 上海浦东孙桥名特水产开发有限公司!上海2001203

采用高度不饱和脂肪酸（HUFA）营养强化的轮虫、轮虫与卤虫组合投喂中华绒螯蟹幼体 ,以各期幼体的存活率为评判指标 ,对不同饵料及其组合的投喂效果进行了探讨。研究结果表明 :轮虫是中华绒螯蟹早期幼体（Ⅰ、Ⅱ期）的适口饵料 ,幼... 详细信息

采用高度不饱和脂肪酸（HUFA）营养强化的轮虫、轮虫与卤虫组合投喂中华绒螯蟹幼体 ,以各期幼体的存活率为评判指标 ,对不同饵料及其组合的投喂效果进行了探讨。研究结果表明 :轮虫是中华绒螯蟹早期幼体（Ⅰ、Ⅱ期）的适口饵料 ,幼体存活率随轮虫密度的增加而逐渐上升 ,但当轮虫数量超过最适密度时 ,幼体存活率反而有所下降。其中 ,未强化的轮虫最适投喂密度为 6 0ind·mL-1,强化轮虫最适密度为40ind·mL-1。状Ⅰ、Ⅱ期投喂 40ind·mL-1轮虫 ,从Ⅲ期开始投喂 10ind·mL-1卤虫无节幼体 ,能较好地满足中华绒螯蟹幼体发育的营养需求 ,提高大眼幼体的存活率。表明强化幼体饵料HUFA特别是EPA和DHA能有效地促进幼体的发育与存活和脱壳率

关键词：中华绒螯蟹幼体发育存活率饵料

BIFURCATIONS OF ROUGH 3-POINT-LOOP WITH HIGHER DIMENSIONS

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Chinese Annals of mathematics,Series B 2003年第1期24卷 85-96页

作者： JIN YINLAI zhu deming ZHENG QINGYU department of mathematics Linyi Teachers' University Linyi 276005 Shandong China. Department of Mathematics East China Normal University Shanghai 200062 China.Department of Mathematics East China Normal University Shanghai 200062 China.Department of Mathematics Linyi Teachers' University Linyi 276005 Shandong China.

The authors study the bifurcation problems of rough heteroclinic loop connecting threesaddle points for the case β1 ＞ 1, β2 ＞ 1, β3 ＜ 1 and β1β2β3 ＜ 1. The existence, number, co-existence and incoexistence of 2-point-loop, 1-homoclinic orbit and 1-periodic orbit are ***, the bifurcation surfaces and existence regions are given.

关键词： Local coordinates Poincare map 1-homoclinic orbit 1-periodic orbit Bifurcation surface