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On hypersurfaces of H2×H2

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Science china Mathematics 2024年第2期67卷 339-366页

作者： dong Gao Hui Ma Zeke Yao School of Science Beijing University of Civil Engineering and Architecture department of Mathematical Sciences Tsinghua University

In this paper, we study hypersurfaces of H2× H2. We first classify the hypersurfaces with constant principal curvatures and constant product angle functions. Then we classify homogeneous hypersurfaces and isoparametric hypersurfaces, respectively. Finally, we classify the hypersurfaces with at most two distinct constant principal curvatures, as well as those with three distinct constant principal curvatures under some additional conditions.

关键词： constant principal curvature homogeneous hypersurface isoparametric hypersurface 53C42 53B25 53C40

Prospect Theory Based Individual Irrationality Modelling and Behavior Inducement in Pandemic Control

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 139-170页

作者： Wenxiang dong H.Vicky Zhao department of Automation BNRistTsinghua UniversityBeijing100084China

Understanding and modeling individuals’behaviors during epidemics is crucial for effective epidemic ***,existing research ignores the impact of users’irrationality on decision-making in the ***,existing disease control methods often assume users’full compliance with measures like mandatory isolation,which does not align with the actual *** address these issues,this paper proposes a prospect theorybased framework to model users’decision-making process in epidemics and analyzes how irrationality affects individuals’behaviors and epidemic *** to the analysis results,irrationality tends to prompt conservative behaviors when the infection risk is low but encourages risk-seeking behaviors when the risk is ***,this paper proposes a behavior inducement algorithm to guide individuals’behaviors and control the spread of *** and real user tests validate our analysis,and simulation results show that the proposed behavior inducement algorithm can effectively guide individuals’behavior.

关键词： Disease spread behavior model irrationality prospect theory

A Study on Sequence Stratigraphy of Mesoproterozoic and Neoproterozoic in Southern North china Platform

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Journal of Earth Science 1996年第1期15卷 13-19页

作者： Zhou Hongrui Wang Ziqiang Cui Xinsheng Lei Zhenyu dong Wenming (department of geology and Mineral Resources, china university of Geosciences, beijing 100083)

The southern part of North china platform is one of the regions where the Mesoproterozoic and Neoproterozoic are well developed and is also an ideal place for the study or sequence stratigraphy. The paper deals mainly with the sequence stratigraphy of Meso-Neoproterozoic in western part of Henan Province. Based on the analysis of sedimentary features, main types and characters of parasequences, integrated with the study of sequence boundary and maximum-flooding surface, the sedimentary systems tracts and sequences are determined. Ruyang Group is divided into 6 third-order sequences Luoyu Group into 2 third-order sequences and Sinian is divided into 3 third-order sequences. Based on the present study, a new scheme about the correlation of Meso-Neoproterozoic Earthen in the region is proposed.

关键词： sequence stratigraphy stratigraphic correlation Proterozoic North china platform.

Pharmacology teaching and its reform in china

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Acta Pharmacologica Sinica 2004年第9期 131-136页

作者： Wei-dong LI, Yuan ZHANG, Cai-li ZHANG, Xiu-mei ZHANGdepartment of Pharmacology, peking university, beijing 100083 department of Pharmacology, Tianjin Medical university, Tianjin 300070 department of Pharmacology, Shandong university, Ji-nan 250012, china.

The general situation of pharmacology teaching in china was introduced and the educational reform in china in recent decade is summarized. The aim of the article is to provide those who are interested in teaching of pharmacology to be acquainted with the teaching of pharmacology, including the teaching of both principles and practice, in china.

关键词： pharmacology teaching reform principles and practice of teaching

Chiral Separation of Esmolol and Terazosin by Cyclodextrinmodified Capillary Zone Electrophoresis

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Chinese Chemical Letters 1998年第6期9卷 565-568页

作者： Yi Yang dong Xue Qin REN Ai Jin HUANG Yi Liang SUN Zeng Pei SUN(department of Chendstry, peking university, beijing 10087)(National Institute for the Control of Pharmaceutical and Biological Products, beijing 100050) peking Univ Dept Chem Beijing 100871 Peoples R China Natl Inst Control Pharmaceut & Biol Prod Beijing 100050 Peoples R China

Cyclodextrin-modified CZE was applied to the chiral separation of two basic drugs, i.e., esmolol and terazosin. Selector screening and concentration optimization experiments were performed. Resolution 3.1 for esmolol, 1.2 for terazosin were achieved when using 60 mmol/L gamma-CD and 60 mmoL/L DM-P-CD, respectively, in 50 mmol/L pH 2.5 sodium phosphate buffer.

关键词： capillary zone electrophoresis chiral separation cyclodextrin esmolol terazosin

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阿普尔加斯与19世纪英国工人运动的发展

史学集刊 2011年第2期 114-120页

作者：宋晓东北京大学历史学系北京100871

19世纪中期,随着新模范工会在各行业的发展,英国工人运动进入了一个新的历史阶段,在阿普尔加斯等人为代表的新一代工会领导人的努力下,工会不仅成功地克服了1866年谢菲尔德暴行带来的巨大危机,而且在各阶级进步人士的帮助下,推动议会在1... 详细信息

19世纪中期,随着新模范工会在各行业的发展,英国工人运动进入了一个新的历史阶段,在阿普尔加斯等人为代表的新一代工会领导人的努力下,工会不仅成功地克服了1866年谢菲尔德暴行带来的巨大危机,而且在各阶级进步人士的帮助下,推动议会在19世纪70年代相继通过了有利于工会运动的立法,使工会从此成为英国产业制度中一个不可缺少的组成部分。而新模范工会所倡导的自助自制精神、阶级合作和劳资和解的政策,不仅为工会运动的合法化开辟了道路,同时也为19世纪中期英国社会的和谐稳定,经济的繁荣发展提供了保障。

关键词：阿普尔加斯新模范工会谢菲尔德暴行

Design and fabrication of Nd-Fe-B magnet with excellent thermal stability

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Journal of Rare Earths 2024年第5期42卷 980-986,I0006页

作者： Rui Han Shengzhi dong dong Li dongmin Zhang Hongsheng Chen Jiyuan Xu George CHadjipanayis Zhuolin Li Ying Zhang Wei Li Division of Functional Materials Research Central Iron and Steel Research InstituteBeijing100081China department of Physics and Astronomy Sharp Lab University of DelawareNewarkDE19716USA beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing100190China

A novel Nd-Fe-B type permanent magnet with excellent thermal stability was designed by Co replacing Fe in the main phase and the grain boundary *** remanence and coercivity temperature coefficient reach 0.058%/℃and 0.465%/℃in the te mperature range from 25 to 100℃,which are much lower than those of commercial Nd-Fe-B *** enhanced Curie temperature is obtained for the novel magnet due to the Co substitution,which significantly improves the operating *** microstructure result reveals that an amorphous phase exists in the intergranular grains which is probably responsible for the deterioration of intrinsic *** work can provide a reference for the design and optimization of components of sintered Nd-Fe-B magnets with excellent thermal stability.

关键词： Thermal stability Remanence temperature coefficient Operating temperature Atomic substitution Rare earths

FORMATION OF MESOPHASE MONO-DOMAINS AND MICRO-STRUCTURES IN THIN FILMS OF A SERIES OF COPOLYETHERS CONTAINING BOTH ODD-NUMBERED METHYLENE UNITS

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Chinese Journal of Polymer Science 2001年第4期19卷 391-397页

作者： Feng-chao Xie Jie-ping Liu dong-hang Yan Tian-bai He Ru-qing Zheng Er-qiang Chen State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, china department of Polymer Science and Engineering College of Chemistry peking university beijing 100871, china Chinese Acad Sci Changchun Inst Appl Chem State Key Lab Polymer Phys & Chem Changchun 130022 Peoples R China peking Univ Coll Chem Dept Polymer Sci & Engn Beijing 100871 Peoples R China

The structural and morphological evolution of mono-domains in thin films has been investigated for a series of liquid crystalline (LC) copolyethers. The copolyethers studied were synthesized by the reaction of 1-(4-hydroxy-4 ' -biphenylyl)-2-(4-hydroxyl-phenyl)propane (TPP) with 1,7-dibromoheptane and 1,11-undecane at different compositions (coTPPs-7/11). In contrast to the solution-cast thin films without annealing, which exhibit the isotropic homogeneous molecular orientation, mono-domains with a homeotropic alignment were found in coTPP-7/11(5/5) after the thin films were annealed in the high-temperature columnar phase (Phi '). Similar to the nucleation process in polymer crystallization, transmission electron microscopic observations show that small mono-domains appear in the initial stage of annealing, where molecules form a uniaxial in-plane chain orientation. With increasing annealing time, the molecular orientation gradually became tilted with respect to the substrate surface, and finally, a uniaxial homeotropic molecular orientation was achieved after a prolonged annealing time. The lateral size of mono-domains was found to increase continuously with annealing time and grew into a circular shape, indicating an isotropic lateral growth scheme which implies a hexagonal molecular packing proved by the electron diffraction experiments.

关键词： main-chain liquid crystalline polymer structure morphology

Ergodicity of 3D Stochastic Burgers Equation

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Acta Mathematica Sinica,English Series 2024年第2期40卷 498-510页

作者： Zhao dong Jiang Lun WU Guo Li ZHOU RCSDS Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190P.R.China department of Mathematics Computational FoundrySwansea UniversitySwansea SA18ENUK College of Mathematics and Statistics Chongqing UniversityChongqing 400044P.R.China

3D Burgers equation is an important model for *** is natural to expect the long-time behaviour for this hydrodynamics ***,there is no result about the long-time behaviour for this deterministic ***,if the system is perturbed by stochastic noise,we establish the existence and uniqueness of invariant measure for 3D stochastic Burgers equation.

关键词： 3D stochastic Burgers equations maximum principle ergodicity