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Shape phase transitions in nuclei:Effective order parameters and trajectories

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 88-97页

作者： ZHANG Yu1,2, HOU ZhanFeng2 & LIU YuXin2,3.1department of physics, liaoning normal university,{3., china 2department of physics and the State Key Laboratory of Nuclear physics and Technology, Peking university, Beijing 100871, china 3.enter of Theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 720000, china 1. department of physics Liaoning Normal University Dalian 116029 China2. Department of Physics and the State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871 China3. Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou 720000 China

We analyze systematically the effective order parameters in nuclear shape phase transition both in experiments and in the interacting boson model. We find that energy ratios and B(E2) ratios can distinguish the first from the second-order phase transition in theory above a certain boson number N (about 50), but in experiments, only those quantities, such as E(L1+)/E(02+) and B(E2; (L+2)1 → L1)/B(E2; 21 → 01), etc., of which the monotonous transitional behavior in the second-order phase transition is broken in the first order phase transition independent of N, are qualified as the effective order parameters. By implementing the originally proposed effective order parameters and the new ones, we find that the isotones with neutron number Nn = 62 are a trajectory of the second order phase transition. In addition, we predict that the transitional behavior of isomer shifts of Xe, Ba isotopes and Nn = 62 isotones is approximately monotonous due to the finiteness of nuclear system.

关键词： nuclear shape phase transition interacting boson model effective order parameter finite particle number effect transition trajectory

Research on sustainable development of small islands in china─taking 12 island counties for examples

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Journal of Geographical Sciences 1999年第1期9卷 51-58页

作者： ZHANG Yao-guang(liaoning normal university,{3., china)

Islands serve as the basis for marine exploitation,and the sustainable development of islands and that of marine exploitation are closely inter-connected. This article inquires into problems on the sustainable develop... 详细信息

关键词： small coastal islands marine exploitation sustainable development

Study on Green Residential Space Design

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IJLAI Transactions on Science and Engineering

IJLAI Transactions on Science and Engineering 2024年第1期2卷 32-37页

作者： Yu Jiang Shenyang normal university No.253.Huanghe North Street Shenyang 110034China

With the ever-changing nature,green ecology has become an international trend of ***,the green ecological design of residential space has become the main melody of people’s *** always implement the concept of ecological and environmental protection in the design process,attach importance to the ecological effect of residential space,carry out reasonable budget and use of environmentally friendly decorative materials,reduce the waste of materials,save money and save resources at the same time,and protect the *** the same time,people began to put their hopes on the residential space design,which made the green residential space design began to *** the bold exploration and practice of designers,the design of green residential space will be endowed with more distinctive characteristics and unique *** from the concept of green design,this paper explores the method of green space design through typical analysis.

关键词： Green Residential space Haze

Theory on the molecular characteristic contour (II)——Molecular intrinsic characteristic contours of several typical organic molecules

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Science china Chemistry 2005年第2期48卷 89-100页

作者： GONG Lidong, ZHAO Dongxia & YANG Zhongzhi department of Chemistry, liaoning normal university, dalian 116029,{3. Correspondence should be addressed to Yang Zhongzhi (email: zzyang@***) Dept. of Chem. Liaoning Normal Univ. Dalian 116029 China

The molecular intrinsic characteristic contour (MICC) is defined based on the clas-sical turning point of electron movement in a molecule. Three typical organic molecules, i.e. methane, methanol and formic acid, were employed as examples for detailed introduction of our method. Investigations on the cross-sections of MICC provide important information about atomic size changing in the process of forming molecules. The electron density distributions on the MICCs of these molecules were calculated and shown for the first time. Results showed that the electron density distribution on the MICC correlates closely with molecular chemical properties, and it provides a new insight into molecular boundary.

关键词： molecular intrinsic characteristic contour (MICC) potential acting on an electron in a molecule electron density organic molecules ab initio method.

α－OXOKETENE　CYCLIC　DITHIOACETALS　CHEMISTRY　──REACTION　OF　α，α－DIOXO（ESTER）KETENE　CYCLIC　DITHIOACETALS　WITH　BUTANONE

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Chinese Chemical Letters 1996年第2期7卷 95-98页

作者： Zai Ming ZHU Yong Ting XU(department of chemistry, liaoning normal university,Delian, 116029)Qun LIU(department of Chemistry,Northeast normal university,Changchun, 13.024)Jie Han HU(dalian Institute of Chemical physics,Academia Sinica,dalian, 116001) liaoning normal UNIV DEPT CHEM DALIAN 116029 PEOPLES R CHINA NE normal UNIV DEPT CHEM CHANGCHUN 130024 PEOPLES R CHINA ACAD SINICA DALIAN INST CHEM PHYS DALIAN 116001 PEOPLES R CHINA

Cyclic dithioacetals of α,α-dioxo (estcr) ketene 3.were reacted with butanone to afford the Michael adducts 4, catalyZed by metal Na. This process provides a new method for the Synthesis of ring-compouds in goob yie... 详细信息

关键词： VERSATILE

Superconductivity of small metal grains

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Science china(physics,Mechanics & Astronomy) 2005年第4期48卷 431-441页

作者： ZHENG Renrong1 CHEN Zhiqian2 & ZHU Shunquan1,3.1. department of physics, Shanghai normal {3., Shanghai 20023., china 2. department of physics, Southwest normal {3., Chongqing 400715, china 3. department of Computer and Electric Technology, Shanghai Business School, Shanghai 201400, china 1. department of physics Shanghai Normal University 200234 Shanghai China 2. department of physics Southwest Normal University 400715 Chongqing China 3. department of Computer and Electric Technology Shanghai Business School 201400 Shanghai China

The formulas of the energy gap and superconducting critical temperature appropriate for systems with both odd and even number of electrons are derived; the bases of the derivations are BCS theory and energy level statistics. Numerical results qualitatively agree with the experimental phenomena. i.e., the superconductivity of small metallic grains will first enhance then decrease to zero when the grain are getting smaller and smaller. The calculations indicate that the above phenomena happen in the metallic grains belonging to Gaussian Orthogonal Ensemble (GOE) and Gaussian Unitary ensemble (GUE) with zero spin; The superconductivity of small metallic grains in Gaussian Symplectic Ensemble (GSE) will monotonically decrease to zero with the decreasing of the grain size. The analyses suggest that the superconductivity enhancements come from pairing and the balance of the strengths between spin-orbital coupling and external magnetic field. In order to take the latter into account, it is necessary to include the level statistics given by Random Matrix Theory (RMT) in describing small metallic grains.

关键词： size effect, superconductivity enhancements, small metallic grains.

BINDING　ENERGY　OF　THE　SHALLOW　DONOR　IN　（CdTe）_m／（ZnTe）_n　STRAINED　DOUBLE　QUANTUM　WELL

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Acta Metallurgica Sinica(English Letters) 1996年第2期9卷 103-108页

作者： XING Jinhai(department of physics,liaoning {3.,Shenyang 11003.,china)HUANG Heluan(department of Electronic Science and Engineering,liaoning {3.,11003.,china) liaoning Univ Shenyang China

In this paper the binding energy of the *** in CdTe/ZnTe strained double quantum well was *** effect of the finite well potential and strain,resulting from the lattice mismatch,on the binding energy of the impurity is included in a variational *** binding energy is obtained as a function of the well width,barrier width,and impurity position in the barrier by using a variational *** result of the present calculation shows that the variational law of the binding energy is similar to that of unstrained materials.

关键词： binding energy shallow donor strained double quantum well CdTe ZnTe

Research on Methods of Ecological Security Assessment of the Middle and Lower Reaches of Liaohe River Based on GIS

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Chinese Journal of Population,Resources and Environment 2005年第4期3卷 20-25页

作者： Wang Geng 1,2 , Nie Baochi 3. Wang Lin 1 & Wu Wei 1 1. School of Environmental and Biological Science and Technology, dalian university of Technology, dalian 116024,{3. 2. Urban and Environmental School, liaoning normal university, dalian 116029,{3. 3. Shenyang Buraue of Water Resources, Shenyang 110013.{3.. School of Environmental and Biological Science and Technology Oalian University of Technology Oalian 116024 China Urban and Environmental School Uaoning Nonnal University Oalian 116029 China Shenyang Buraue of Water Resources Shenyang 110013 China

Ecological security assessment and early warning research possess the attributes of spatiality, non-linearity and randomicity, so we must process much spatial information. Spatial analysis and data management are the advantages of GIS, which can define distribution trend and spatial relations of environmental factors, and show ecological security pattern graphically. Spatial differences of ecological security assessment based on GIS are discussed in this paper, of which the middle and lower reaches of the Liaohe River is taken as a study case. First, to work out pressure-state-response (P-S-R) assessment indicators system, and investigate in person and gather information; second, to digitize the watershed; third, to quantize and calculate by the fuzzy method; last, to construct GIS grid database, and expound spatial differences of ecological security by GIS interpolation and assembly analysis.

关键词： the middle and lower reaches of the Liaohe River ecological security assessment indicators system GIS spatial differences

Study on the two and three-parameter working stability regions of 3.-TZP suspension

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Science china(Technological Sciences) 2006年第5期49卷 547-568页

作者： CHEN Youqiang1, 2, ZHANG Xinni3. CHEN Sha’ou3.& QI Ping3.1. department of Chemistry, Qingdao university, Qingdao 266071, china 2. department of Chemistry, Tsinghua university, Beijing 100084, china 3. department of physics, Qingdao university, Qingdao 266071, china 1. department of Chemistry Qingdao University Qingdao 266071 China 2. department of Chemistry Tsinghua University Beijing 100084 China 3. department of physics Qingdao University Qingdao 266071 China

We determined the variation tendency of viscosity (η) at various solids load- ing (α) for 3.-TZP suspension as a function of dispersant concentration (Cw) using vis- cosity measurement, measured the diameter of particles as a function of Cw in very dilute suspension using light scattering method, and obtained the surface features of the sedi- ment of suspension with different Cw using SEM. We also discussed the influence of the microstructure of adsorbed polymer layers on particles and their interactions in the dis- persing medium on the stability of suspension. Then two different stable states and two different unstable states for 3.-TZP suspension were given. Accordingly, the (Cw, η), (Cw, α), and (α, η) two-parameter, and (Cw, α, η) three-parameter stability maps were con- structed. Based on the DLVO theory calculations, the dispersant concentration, particle distance (r), and interparticle potential energy (VT) maps with various solids loading for 3.-TZP aqueous suspension were also constructed. In (Cw, r) two-parameter coordinate system, the stable motion region map for particles was established. The Cw, α, and VT,max (the highest potential energy) surface of the potential barrier map was obtained through calculation and simulation on the basis of the surfaces of Cw, r, VT maps introduced above. The (Cw, α) two-parameter stability map was then obtained from the Cw, α, VT,max map. The results showed that this theoretical map can qualitatively prove the experimentally obtained results—the existence of different dispersed states of particles in suspension system and the variation tendency of suspension stability with changing each parame- ter—were reasonable.

关键词： 3.-TZP, suspension, stability, DLVO theory, interparticle potential energy.