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陕西省水资源可持续发展的误区及建议

陕西师范大学学报（自然科学版） 2009年第S1期37卷 72-74页

作者：王东咸阳师范学院人事处陕西咸阳712000

陕西省是一个水资源十分紧缺的省份,水的供给不足以及由此导致的生态环境问题,一直是全省经济与社会发展的制约因素.从分析陕西省水资源基本情况和特点入手,分析了目前水资源可持续发展方面的误区,并提出了解决陕西省水资源短缺现状及... 详细信息

陕西省是一个水资源十分紧缺的省份,水的供给不足以及由此导致的生态环境问题,一直是全省经济与社会发展的制约因素.从分析陕西省水资源基本情况和特点入手,分析了目前水资源可持续发展方面的误区,并提出了解决陕西省水资源短缺现状及实现水资源可持续发展的建议.

关键词：水资源短缺可持续发展误区

Fabrication, microstructure and properties of SiCp/Cu heat sink materials

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Rare Metals 2006年第z2期25卷 232-236页

作者： KANG Suk-bong Korea Institute of Machinery and Materials 66 Sangnam-dong Changwon 641-010 Korea

Cu-coated powder was fabricated by electroless plating process, and the composition and morphology of coated powder were studied. Moreover, Cu-3., 40, 50 vol.%SiCp heat sink materials were fabricated by hot pressing using coated and uncoated powder. And the microstructure and thermophysical properties of the heat sink materials were also studied. The results show that SiCp particles distribute uniformly in heat sink materials and the interface between SiCp particles and Cu matrix is clear and well bonded. On the condition of same volume fraction of SiCp, the thermal conductivity of the material using coated powder is larger than that of the material using uncoated powder. Under experiment conditions, the thermal conductivity and coefficient of thermal expansion of Cu-3. vol.%SiCp heat sink material is 2.6.2.W·m-1·K-1 and 9.9×10-6/K (3.-2.0 ℃) respectively. It provides important reference data for future experiments.

关键词： heat sink material electroless copper plating coefficient of thermal expansion thermal conductivity

Free Volume Changes in γ-Irradiated Polyethylene and Polytetraflourethylene

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Journal of Materials Science & Technology 2000年第3期16卷 302-304页

作者： Xianyi ZHOU (Dept. of Modern physics, University of Science and Technology of China, Hefei 2.002., China) Linhua ZHAI ({3. of physics, Anhui {3. University, Wuhu 2.1000, China) Jiangfeng DU and Rongdian HAN ({3. of Modern physics, Univers department of Modern physics University of Science and Technology of China Hefei 230027 China department of physics Anhui Normal University Wuhu 241000 China

Positron lifetime spectrum was measured and the change of the free volume was studied for commercial polyethylene (PE) and polytetrafluoroethylene (PTFE) during 7-irradiation processing up to 2.5 kGy. The free volume size increases but the crystallinity decreases as irradiation dose increases in PE. Both qualities (free volume size and crystallinity) in PTFE display an opposite behavior. The fractional free volume reduces monotonically with increasing irradiation dose in both PE and PTFE. The competition between the crosslinkmg and the splitting decomposition in polymers can be used to understand the free volume changes with irradiation dose.

关键词： PTFE Irradiated Polyethylene and Polytetraflourethylene

Charge transfer in H~+ +H and H~+ +He~+ collisions at intermediate and high energies using an asymptotic two-state atomic expansion method

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原子与分子物理学报 1998年第2期 9-18页

作者： Zhou Xiaoxin  Dong Chenzhong  Zhang Xianzhou  Li Shuzhong  department of physics, Northwest {2. University Lanzhou 73.070  department of physics, Henan {2. University Xinxiang 453.02

ＣｈａｒｇｅｔｒａｎｓｆｅｒｉｎＨ＋＋ＨａｎｄＨ＋＋Ｈｅ＋ｃｏｌｉｓｉｏｎｓａｔｉｎｔｅｒｍｅｄｉａｔｅａｎｄｈｉｇｈｅｎｅｒｇｉｅｓｕｓｉｎｇａｎａｓｙｍｐｔｏｔｉｃｔｗｏｓｔａｔｅａｔｏｍｉｃｅｘｐａｎｓｉｏｎ... 详细信息

ＣｈａｒｇｅｔｒａｎｓｆｅｒｉｎＨ＋＋ＨａｎｄＨ＋＋Ｈｅ＋ｃｏｌｉｓｉｏｎｓａｔｉｎｔｅｒｍｅｄｉａｔｅａｎｄｈｉｇｈｅｎｅｒｇｉｅｓｕｓｉｎｇａｎａｓｙｍｐｔｏｔｉｃｔｗｏｓｔａｔｅａｔｏｍｉｃｅｘｐａｎｓｉｏｎｍｅｔｈｏｄ▲ＺｈｏｕＸｉａｏｘｉ...

关键词： Charge transfer Collision Cross section Books Classification Number of China: O552.5

Modified Chaplygin gas as an interacting holographic dark energy model

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Science China(physics,Mechanics & Astronomy) 2010年第4期53卷 598-606页

作者： WU YaBo, YANG WeiQiang, WANG Cong & WANG Lei department of physics, Liaoning {2. University, Dalian 11602., China 1. department of physics Liaoning Normal University Dalian 116029 China

The modified Chaplygin gas (MCG) as an interacting model of holographic dark energy in which dark energy and dark matter are coupled together is investigated in this paper. Concretely, by studying the evolutions of related cosmological quantities such as density parameter Ω, equation of state w, deceleration parameter q and transition redshift zT, we find the evolution of the universe is from deceleration to acceleration, their present values are consistent with the latest observations, and the equation of state of holographic dark energy can cross the phantom divide w = -1. Furthermore, we put emphasis upon the geometrical diagnostics for our model, i.e., the statefinder and Om diagnostics. By illustrating the evolutionary trajectories in r - s, r - q, w -w and Om planes, we find that the holographic constant c and the coupling constant b play very important roles in the holographic dark energy (HDE) model. In addition, we also plot the LCDM horizontal lines in Om diagrams, and show the discrimination between the HDE and LCDM models.

关键词： modified Chaplygin gas interacting holographic dark energy geometrical diagnostics

Codimension 3.nonresonant bifurcations of homoclinic orbits with two inclination flips

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Science China Mathematics 2005年第2期48卷 248-260页

作者： SHUI Shuliang & ZHU Deming College of Mathematics and physics, Zhejiang normal University, Jinhua 3.2}004, China {2. of Mathematics, East China normal University, Shanghai 2.0062. China 1. College of Mathematics and physics Zhejiang Normal University 321004 Jinhua China 2. department of Mathematics East China Normal University 200062 Shanghai China

Homoclinic bifurcations in four-dimensional vector fields are investigated by setting up a local coordinate near a homoclinic orbit. This homoclinic orbit is principal but its stable and unstable foliations take inclination flip. The existence, nonexistence, and uniqueness of the 1-homoclinic orbit and 1-periodic orbit are studied. The existence of the two-fold 1-periodic orbit and three-fold 1 -periodic orbit are also obtained. It is indicated that the number of periodic orbits bifurcated from this kind of homoclinic orbits depends heavily on the strength of the inclination flip.

关键词： bifurcation, homoclinic orbit, non-resonance, inclination flip, 1-periodic orbit.

Description of Hypernucleus _(ΛΛ)~6He by the ΛΛ_α Model

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Chinese journal of nuclear physics 1994年第1期16卷 21-25页

作者： Li Chuliang Duan Yiwu (department of physics.Xiangtan {2. College.Xiangtan 411100) 湘潭师范学院物理系湖南湘潭 411100 湘潭师范学院物理系湖南湘潭

Based on the ΛΛα model,a variational calculation for the double-Λhypernucleus ΛΛ6He is carried out with the harmonic oscillator *** thevarious Λ-Λ interactions proposed,the Gaussian type with or without repulsive core *** influence on eigenenergy,structure and interparticle correlation is studiedby observing the shape-density.

关键词： Hypernucleus Harmonic oscillator Repulsive core

The study of energy bands in nucleus ^(102.Zr

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Science China(physics,Mechanics & Astronomy) 2010年第1期53卷 106-110页

作者： DONG GuoXiang 1,2., YU ShaoYing 1,2.3., LIU YanXin 1 , SHEN CaiWan 1,2.4 & DONG YongSheng 1,2.5I School of Science, Huzhou Teachers College, Huzhou 3.3.00, China 2.School of Science and Information Engineering, Zhejiang normal University, Jinhua 3.0}000, China 3.Institute of Theoretical physics, Chinese Academy of Sciences, Beijing 100080, China 4 Center of Theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 73.000, China 5 {3. of physics, Jining Teachers College, Jining 012.00, China 1. School of Science Huzhou Teachers College Huzhou 313000 China2. School of Science and Information Engineering Zhejiang Normal University Jinhua 321000 China3. Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China4. Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China5. Department of Physics Jining Teachers College Jining 012000 China

Theoretical calculations of the energy bands in nucleus 102.Zr are carried out by taking the projected shell model approach, which has reproduced the experimental data. In addition, by analyzing band-head energies, corresponding configurations of yrast band, quasi-particle rotational bands and side bands, we have worked out the microscopic formation mechanism of axially symmetric deformation bands: The low-excitation deformation bands are attributed to the high-j intruder states 1g 7/2.and 1h 11/2.in the N=4, 5 shells; the quasi-particles in the orbit v5/2.[53.0}, v3.2.[411] and v3.2.[413. in particular play an important role in the deformation of 102.Zr.

关键词： projected shell model yrast band quasi-particle rotational band side band

Effect of annealing treatment on the structural, optical, and electrical properties of Al-doped ZnO thin films

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Rare Metals 2007年第3期26卷 247-253页

作者： LI Li FANG Liang CHEN Ximing LIU Gaobin LIU Jun YANG Fengfan FU Guangzong KONG Chunyang College of Photoelectric Engineering Chongqing University of Posts and Telecommunications Chongqing 400065 China department of Applied physics Chongqing University Chongqing 400044 China department of physics Chongqing Normal University Chongqing 400047 China

Highly conductive and transparent Al-doped ZnO （AZO） thin films were prepared from a zinc target containing Al （1.5 wt.%） by direct current （DC） and radio frequency （RF） reactive magnetron sputtering. The structural, optical, and electrical properties of AZO films as-deposited and submitted to annealing treatment （at 3.0 and 400℃, respectively） were characterized using various techniques. The experimental results show that the properties of AZO thin films can be further improved by annealing treatment. The crystallinity of ZnO films improves after annealing treatment. The transmittances of the AZO thin films prepared by DC and RF reactive magnetron sputtering are up to 80% and 85% in the visible region, respectively. The electrical resistivity of AZO thin films prepared by DC reactive magnetron sputtering can be as low as 8.06 x 10-4 Ωcm after annealing treatment. It was also found that AZO thin films prepared by RF reactive magnetron sputtering have better structural and optical properties than that prepared by DC reactive magnetron sputtering.

关键词： AZO thin films structure optical and electrical properties annealing transmittance spectra electrical resistivity