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A COMPARATIVE STUDY ON THE CARTOGRAPHIC HISTORIES BETWEEN china AND THE WEST

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Journal of Geographical Sciences 1996年第2期6卷 89-96页

作者： Lu Huancheng (department of Geography, Siping teachers’ college, Jilin 13600 People’s Republic of china) DeptGeog Siping Teachers' Coll Jilin 13600 China

Analysis of space shifting of geodetic center of china and the West,reveals that the china's geodetic center has been in coincidence with its political center. Furthermore the development of the maps in Europe was controlled by developmat of economy. Thereupon, maps in china and the West were developing in their own ways, and thus formed two different cartographic *** china has a splendid cartogrphic history, it has not yet got many great breakthroughs. The reasons are as follows : 1. The theory of round earth has never occupied the ruling place, instead, the theory of flat earth took the dominant position. Thus the geodetic frameworks of china are not scientific. 2. Owing to the trammels of the theory that china is the whole earth, the Chinese geodetic workers have been limited in china's area. 3. Exchange between the East and the Weat is too late. The Chinese geodetic workers took a long time to accept the West geodetic technology. on the contrary, the West has absorbed the geodetic technology and results of china. 4. china's anciat gcodotic workers usually stopped after getting a little knowledge of a subject. They should have made great breakthroughs in geodetic area. Nevertheless, they failed.

关键词： cartographic history theory of flat earth geodetic center

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原发性肾盂黏液腺癌混合印戒细胞癌1例报告

中华泌尿外科杂志 2024年第8期45卷 626-628页

作者：孙梦伟张庆玲吴岩橙王耀辉徐彦韩杰南京中医药大学附属医院江苏省中医院泌尿外科南京210029 南京中医药大学附属医院江苏省中医院病理科南京210029

肾盂黏液腺癌临床罕见。本文报道1例原发性肾盂黏液腺癌混合印戒细胞癌患者,因右侧腰痛入院,完善检查诊断为右肾结石伴积水和感染、右肾脓肿、右肾无功能。先后两次行右肾穿刺造瘘术,引流出黄绿色脓性液体,后行机器人辅助腹腔镜根治性... 详细信息

肾盂黏液腺癌临床罕见。本文报道1例原发性肾盂黏液腺癌混合印戒细胞癌患者,因右侧腰痛入院,完善检查诊断为右肾结石伴积水和感染、右肾脓肿、右肾无功能。先后两次行右肾穿刺造瘘术,引流出黄绿色脓性液体,后行机器人辅助腹腔镜根治性右肾切除术。术后病理诊断为右侧肾盂黏液腺癌(黏液腺癌混合印戒细胞癌)。术后11个月应用亚叶酸钠+奥沙利铂+5-氟尿嘧啶化疗12个周期,影像学检查无复发转移征象。

关键词：肾盂黏液腺癌印戒细胞癌病理化疗机器人手术

UNIFORM PERSISTENCE AND GLOBAL ATTRACTIVITY FOR NONAUTONOMOUS COMPETITIVE SYSTEMS WITH DISPERSION

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Journal of Systems Science & Complexity 2002年第3期15卷 307-314页

作者： SONGXinyu CHENLansun departmentofmathematics XingangTeachersCollegeHenan464000China Instituteofmathematics AcademyofMathematicsandSystemsScienceChinesAcademyofSceiencesBeijing100080China

In this paper, we consider a nonautonomous competitive model with dispersion and a finite number of discrete delays. The system, which consists of two Lotka-Volterra patches, has two competitors: one can disperse between the two patches, but the other is confined to one patch and cannot disperse. Our purpose is to demonstrate that the dispersion rates have no effect on the uniform persistence of the solutions of the system. Furthermore, we establish the conditions under which the system admits a positive periodic solution which attracts all solutions.

关键词： Uniform persistence global attractivity dispersion.

THE CRITERIA OF ULTIMATE BOUNDEDNESS FOR NONAUTONOMOUS DIFFUSIVE LOTKA-VOLTERRA SYSTEMS IN TWO HETEROGENEOUS PATCHES

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Journal of Systems Science & Complexity 2001年第2期14卷 179-188页

作者： LI Xuezhi (department of mathematics, Xinyang teachers college, Henan 464000, china) GENI Gupur (Deportment of mathematics, Xinjiang University, Urumqi 830046, china) ZHU Guangtian (Institute of Systems Science, Academy of mathematics and Systems Science, 信阳师范学院河南 464000 新疆大学新疆乌鲁木齐 830046 中科院系统科学所北京 100080

In this paper, a set of sufficient conditions is obtained for the ultimate boundedness of nonautonomous n-species diffusive Lotka-Volterra sub-models in two heterogeneous patches. The sub-models are the Lotka-Volterra tree systems, including the Lotka-Volterra chain systems and the Lotka-Volterra models between one and multispecies. The criteria in this paper are in explicit forms of the parameters and thus are easily verifiable.

关键词： Ultimate boundedness diffusive Lotka-Volterra systems patches.

Structure and Pozzolanic Activity of Calcined Coal Gangue during the Process of Mechanical Activation

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Journal of Wuhan University of Technology(Materials Science) 2009年第2期24卷 326-329页

作者：郭伟 department of Material Engineering Yancheng Institute of Technology Institute of Material Science and Engineering Nanjing University of Technology

On the basis of analyzing coal gangue＇s chemical and mineral compositions, the structure change of coal gangue during the mechanical activation was investigated by XRD, FTIR, NMR, and the mechanical strength of the cement doped coal gangue with various specific surface area was tested. The experimental results indicate that, the lattice structure of metakaolin in coal gangue samples calcined at 700 ℃ disorganizes gradually and becomes disordered, and the lattice structure of α-quartz is distorted slightly. The pozzolanic activity of the coal gangue increases obviously with its structural disorganization.

关键词： coal gangue mechanical activation structure NMR tetrahedron

Studies on the Relation between the Composition of Thermal Sensitive MnZn Ferrite and Curie Temperature

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Journal of Materials Science & Technology 2000年第2期16卷 209-210页

作者： Mengkui WANG (department of Physics, Jinzhou teachers college, Jinzhou 121003, china) Junyue WANG (Jinzhou Audio-Visual Education Center, Jinzhou 121000, china) Ke SUN (department of Physics, Northeastern University, Shenyang 110006, china) department of Physics Jinzhou Teachers College Jinzhou 121003 China Jinzhou Audio-Visual Education Center Jinzhou 121000 China department of Physics Northeastern University Shenyang 110006 China

Thermal sensitive MnZn ferrite is a kind of soft magnetic ferrite material with lower Curie temperature (Tc) and can be used to make many kinds of magnetic thermal sensitive sensors with high sensitivity. In this paper, the relation between the composition of thermal sensitive ferrite and TC was studied. It was found that TC changes linearly with ZnO extent when the content of Fe2O3 is fixed. Based on lots of experiments, an experimential formula to determine was given out.

关键词： Studies on the Relation between the Composition of Thermal Sensitive MnZn Ferrite and Curie Temperature ZnO

Theoretical Study on the Reaction Mechanism of F2+2HBr = 2HF+Br2

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Chinese Journal of Structural Chemistry 2005年第11期 110-115+12页

作者： SUN De-Shenga, b WANG Zun-Yaob YANG Chun-Shengb a (School of Chemistry and Chemical Engineering, Nanjing University of Technology, Jiangsu, Nanjing 210009, china) b(department of Chemical Engineering, yancheng Institute of Technology, Jiangsu, yancheng 224003, china)

The gas phase reaction mechanism of F2 + 2HBr = 2HF + Br2 has been investigated by (U)MP2 at 6-311G** level, and a series of four-center and three-center transition states have been obtained. The reaction mechanism was achieved by comparing the activation energy of seven reaction paths, i.e. the dissociation energy of F2 is less than the activation energy of the bimolecular elementary reaction F2 + HBr → HF + BrF. Thus it is theoretically proved that the title reaction occurs more easily in the free radical reaction with three medium steps.

关键词： (U)MP2 transition state reaction mechanism free radical reaction.

Optimal value functions of generalized semi-infinite min-max programming on a noncompact set

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Science china mathematics 2005年第2期48卷 261-276页

作者： WANG Changyu, YANG Xiaoqi & YANG Xinmin Institute oi Operations Research, Qufu Normal University, Qufu 273165, china department of Applied mathematics, Dalian University of Technology, Dalian 116024, china department of Applied mathematics, The Hong Kong Polytechnic University, Hong Kong, china department of mathematics, Chongqing Normal University, Chongqing 400047, china Institute of Operations Research Qufu Normal University Qufu China department of Applied mathematics Dalian University of Technology Dalian China department of Applied mathematics The Hong Kong Polytechnic University Hong Kong China department of mathematics Chongqing Normal University Chongqing China

In this paper, we study optimal value functions of generalized semi-infinite min-max programming problems on a noncompact set. Directional derivatives and subdifferential characterizations of optimal value functions are given. Using these properties,we establish first order optimality conditions for unconstrained generalized semi-infinite programming problems.

关键词： optimal value function, directional derivative, subdifferential, semi-infinite programming, first order optimality condition.

Solving and Applying a Class of Block-diagonal Structured Large Linear Programming

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Systems Science and Systems Engineering 1998年第2期8卷 93-99页

作者： SHENG Jie department of mathematics, teachers college, Yangzhou University CHENG Jieling Departemt of Irrigation, Agriculture college, Yangzhou University CHEN Yixin department of Computer Science, University of Science and Technology of china

Using large block diagonal structured linear problem as illustration, we present the "gradient simplex" method for solving large linear *** solving some large block diagonal structured linear problem with fewer coupling constrants, this method is much faster then the simplex method, and can surmount the capacity and speed restrictions of computer to certain *** this paper, we discuss the efficiency and applicability of the method and analysis its performance in the examples of economic development optimize programming model.

关键词： linear programming method