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Geomorphologic evolution and environmental changes in the Shaluli Mountain region during the Quaternary

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Chinese Science Bulletin 2005年第1期50卷 52-57页

作者： ZHOU Shangzhe1.2. XU Liubing1. CUI Jianxin1. ZHANG Xiaowei1.& ZHAO Jingdong1.1. National Laboratory of Western{1.’s Environmental Systems of Ministry of Education of{1. and {2. of Geography, Lan- zhou university, Lanzhou 730000,{1. 2. {2. of Geography, South{1. normal university, Guang- zhou 51.631.{1. National Laboratory of Western china’s Environmental Systems of Ministry of Education of china and {2. of Geography Lanzhou University Lanzhou China department of Geography South China Normal University Guangzhou China

Geologic and geomorphologic evidence from the Shaluli Mountain indicates that the planation surface that formed in the Late Tertiary disintegrated during the Late Pliocene-Early Quaternary. At the same time, rift ba- sins appeared on some parts of the planation surface, and began to accumulate fluvial-lacustrine sediment. These are interpreted as being the response of this region to Phase-A of the Qingzang Tectonic Movement. After this, the Shaluli Mountain continued to rise in several pulses. Faulting and incision by some large tributaries of the Jinsha and Yalong Rivers resulted in several rift river valleys and the earliest terraces. Generally, the planation surface in this region had been uplifted to about 3500—3700 m a.s.l. no later than 550—600 ka BP, after the Kunlun-Huanghe Tectonic Move- ment, and coupled with global glacial climate, and resulted in the earliest glaciation recognized so far in the Hengduan Mountains. At the same time, loess was deposited in the Ganzi area of the northern Shaluli Mountain. During the last glacial period, the Shaluli Mountain approached its present altitude and developed several large ice caps, such as the Daocheng Ice Cap and Xinlong Ice Cap, as well as several huge valley glaciers. These paleoglaciers produced some of the most spectacular glacial topography on the Tibetan Pla- teau.

关键词：地形学环境变化 Shaluli山脉展平面西藏高原 ESR-年代测定

Constraints on Cardassian universe from Gamma ray bursts

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Science china({1.,Mechanics & Astronomy) 2010年第9期53卷 1720-1725页

作者： WANG TaiShan1 & LIANG Nan2.1 department of physics & Center for Astrophysics,Tsinghua university,Beijing 100084,china 2.department of Astronomy,Beijing normal university,Beijing 1.0875,china department of {1. & Center for Astro{1. Tsinghua University Beijing China department of Astronomy Beijing Normal University Beijing China

Constraints on the original Cardassian model and the modified polytropic Cardassian model are examined from the recently derived 42.gamma-ray bursts(GRBs) data calibrated with the method that can avoid the circularity *** results show that GRBs can be an optional observation to constrain the Cardassian *** the GRBs data with the newly de-rived size of baryonic acoustic oscillation peak from the Sloan Digital Sky Survey(SDSS),and the position of the first acoustic peak of the Cosmic Microwave Background radiation(CMB) from Wilkinson Microwave Anisotropy Probe(WMAP),we find Ωm0=0.2.+0.02.0.02.n=0.06+0.07-0.08(1.) for the original Cardassian model,and Ωm0=0.2.+0.2.-0.02.n=-0.09+0.2.-1.91.β=0.82.2.1.-0.62.1.) for the modified polytropic Cardassian model.

关键词： Cardassian Gamma ray burst Cosmic Microwave Background baryonic acoustic oscillation

An initial note on quasi- stationary, cold-core Lanyu eddies southeast off Taiwan Island

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Chinese Science Bulletin 2003年第19期48卷 2101-2107页

作者： JING Chunsheng1.2.& LI Li1.1. Third Institute of Oceanography, State Oceanic Administration, Xiamen 361.05,{1. 2. department of Oceanography, Xiamen {2., Xiamen 361.05,{1. Third Institute of Oceanography State Oceanic Administration Xiamen China department of Oceanography Xiamen University Xiamen China

Drifting buoys, satellite altimetry and satellite-derived sea surface thermal images are used to identify the existence of a large cold-core, cyclonic Kuroshio frontal eddy between Hengchun Peninsula and Lanyu, southeast off Taiwan Island around March 1.96. The cold eddy accompanies an offshore meander of the Kuroshio near Lanyu, about 70 km and 1.0 km in horizontal zonal and meridional scales, respectively. The cold eddy is different from normal Kuroshio frontal eddies for its persisting of about {1.months near Lanyu. Supporting evidence suggests that the Kuroshio intruded into the South china Sea (SCS, hereafter) forming a loop-like structure during the persisting period of the cold eddy and that similar eddies occur occasionally in the same location. Compared with the corresponding studies in the Gulf of Mexico, it is suggested that Lanyu cold eddies are SCS analogues of Tortugas eddies found in the southern Straits of Florida. Overshooting of the meandering Kuroshio when it leaves the SCS and effects from conservation of potential vorticity are the possible mechanism of eddy genesis.

关键词：台湾省黑潮暖流涡流寒潮飓风

A study of two-dimensional magnetic polaron

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Science china({1.,Mechanics & Astronomy) 2006年第4期49卷 421-429页

作者： LIU Tao1. ZHANG Huaihong1. FENG Mang1.2.& WANG Kelin1.3 1. School of Science, Southwest {1. of Science and Technology, Mianyang 62.01., china 2. Wuhan Institute of {2. and Mathematics, Chinese Academy of Sciences, Wuhan 430070, china 3. department of Modern {2., {1. of Science and Technology of china, Hefei 2.002., china School of Science Southwest University of Science and Technology Mianyang China Wuhan Institute of physics and Mathematics Chinese Academy of Sciences Wuhan China department of Modern {1. University of Science and Technology of China Hefei China

By using the variational method and anneal simulation, we study in this paper the self-trapped magnetic polaron (STMP) in two-dimensional anti-ferromagnetic material and the bound magnetic polaron (BMP) in ferromagnetic material. Schwinger angular momentum theory is applied to changing the problem into a coupling problem of carriers and two types of Bosons. Our calculation shows that there are single-peak and multi-peak structures in the two-dimensional STMP. For the ferromagnetic material, the properties of the two-dimensional BMP are almost the same as that in one-dimensional case; but for the anti-ferromagnetic material, the two-dimensional STMP structure is much richer than the one-dimensional case.

关键词： self-trapped magnetic polaron, bound magnetic polaron, impurity potential, anti-ferromagnet.

Doubly contracted CI method and applications

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Science china Chemistry 2004年第4期47卷 276-282页

作者： WANG Yubin1. HAN Huixian1. ZHAI Gaohong2.,SUO Bin1.& WEN Zheny1.2.1. Institute of Modern physics, Northwest university, Xian 71.069,{2. 2. Laboratory of Physico-Inorganic Chemistry, department of Chemistry, Northwest university, Xian 71.069,china Correspondence should be addressed to Wen Zhenyi Institute of Modern physics Northwest University Xian China Laboratory of Physico-Inorganic Chemistry Department of Chemistry Northwest University Xi’an China

Based on the hole-particle correspondence an approximate so-called doubly contracted CI scheme is proposed. Examples calculated based on the doubly contracted CI (DCCI) scheme show that the number of configurations after contraction is reduced by three orders of magnitude, and the computation time is reduced by an order of magnitude. The examples also show that compared with experiments the DCCI and uncontracted CI have similar and reasonable accuracy to some spectroscopic parameters.

关键词： doubly contracted CI hole-particle symmetry approximate MRCI

Analysis on cohesive crack opening displacement considering the strain softening effect

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Science china({1.,Mechanics & Astronomy) 2006年第1期49卷 88-101页

作者： WANG Limin1. XU Shilang2.& ZHAO Xiqiang3 1. Mechanics {1., Shandong university of Technology, Zibo 2.5049,{2. 2. Civil Engineering {1., Dalian university of Technology, Dalian 1.602.,{2. 3. Mathematics {1., Ocean university of{2., Qingdao 2.6071.{2. Mechanics department Shandong University of Technology Zibo China Civil Engineering department Dalian University of Technology Dalian China Mathematics department Ocean University of China Qingdao China

In order to investigate the crack propagation in quasi-brittle materials like rock, ceramic and concrete, Hillerborg and his co-researchers abstracted the fracture process zone in front of a stress free crack in terms of a “fictitious crack zone”. On the fictitious crack zone, cohesive stresses distribute following a given softening relationship of stress vs. crack opening. Based on the polynomial or power series expression of cohesive crack opening displacement, the relationship of the cohesive stress vs. the crack opening displacement is established using elastic theory and integral equation, and some unknown physics variables are obtained using variation approach. The calculation results gained in this paper are close to the experimentally test ones.

关键词： cohesive crack, softening, dissipation work, variation approach.

Silicon nanoporous pillar array and its surface copper deposition

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Chinese Science Bulletin 2005年第14期50卷 1424-1428页

作者： FU Xiaonan1.2.3, CHAI Huadou1.2.& LI Xinjian1.2.1. department of physics, Zhengzhou {2., Zhengzhou 450052. china 2. Key Laboratory of Material physics (Zhengzhou {2.), Ministry of Education, Zhengzhou 450052. china 3. department of Mathematics and physics, Henan {2. of Tech- nology, Zhengzhou 450052. china department of {1. Zhengzhou University Zhengzhou China Key Laboratory of Material physics (Zhengzhou {1.) Ministry of Education Zhengzhou China department of Mathematics and {1. Henan University of Technology Zhengzhou China

Silicon nanoporous pillar array (Si-NPA) has been prepared by a hydrothermal etching technique. Using Si-NPA as substrate, a Cu/Si-NPA nanocomposite thin film has been obtained with immersion plating method. Morpho- logical and structural analysis indicates that Si-NPA is a typical structural composite system characterized by a triple hierarchical structure, i. e. the array of micron-sized silicon pillars, the nanopores densely distributed on the surface of the pillars, and the silicon nanocrystallites that constitute the pore walls. Cu/Si-NPA inherits the morphological character- istics of Si-NPA. The compactability of the deposited copper nanoparticles varies alternatively with the local geometrical features of Si-NPA and forms a quasi-periodical pattern. Such an experimental phenomenon is attributed to the veloc- ity dependence of the copper deposition upon the local geo- metrical features of Si-NPA. These results indicate that Si-NPA might be used as an ideal template for preparing specially patterned, structured or functionalized metal/ sili- con nanocomposite systems.

关键词：硅元素薄膜蚀刻技术电镀技术

High resolution stalagmite δ1.O records over the past 1.00 years from Dongge Cave in Guizhou

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Science Bulletin 2005年第10期50卷 1003-1008页

作者： HE Yaoqi1. WANG Yongjin1. KONG Xinggong1. & CHENG Hai2. 1. College of Geography Science, Nanjing {1. university, Nanjing 2.0097,{2. 2. department of Geology and Geophysics, Minnesota university, Mineapolis MN 55455, USA College of Geography Science Nanjing Normal University Nanjing China department of Geology and Geo{1. Minnesota University Mineapolis USA

Based on MC-ICP-MS U-series dating and stable O-isotope analysis results, a 4―5 years resolution monsoon record over the past 1.00 years has been estab- lished for two stalagmites from Dongge Cave, Guizhou. The high resolution oxygen isotope record serves as a proxy for variations in rainfall of Asian southwest monsoon over the Yunnan-Guizhou Plateau. A close relation of the δ 1.O record with the ?1.C record from tree rings largely reflects impact of centennial-scale solar activity on the monsoon climate changes. The conspicuous decrease in the δ 1.O value at AD 1.2. indicates an abrupt increase in monsoon rainfall, sug- gesting that an atmospheric-oceanic couple over the tropical Indian Ocean plays an important role in rapid increase of the Northern Hemisphere temperature over the last century.

关键词： cave stalagmite oxygen isotope southwest monsoon solar activity Guizhou.

Pressure-induced crystallite breaking in La_(0.7)Sr_(0.3)Mn_(0.9)Fe_(0.1.O_3 nanosolids

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Chinese Science Bulletin 1998年第6期43卷 458-461页

作者： ZHENG Fanlei 1. 2. SUI Yu 1. 3, XU Dapeng 1.and SU Wenhui 1. 4 1. {1. of physics, Jilin {2., Changchun 1.002., china 2. Changchun Institute of physics, Chinese Academy of Sciences, Changchun 1.002., china 3. Institute of Metal R department of {1. Jilin University Changchun Chinas Changchun Institute of physics Chinese Academy of Sciences Changchun China Institute of Metal Research Chinese Academy of Sciences Shenyang China International Center for Materials physics Chinese Academy of Sceinces Shenyang China Center for Condensed Matter and Radiation physics CCAST (World Lab.) Beijing China

In the compacting process of the La 0.7Sr 0.3Mn 0.9Fe 0.1. 3 nanosolids under the pressure range of 0.0-4.5 GPa, the apparent pressure-induced crystallite breaking phenomenon in these nanosolids was observed. With increasing pressure up to 4.5 GPa, the average grain size decreases by 46% while the magnetization of nanosolids decrease by 40% and their coercive increases by 35%. This kind of breaking has a close relation to the existence of oxygen deficiency in La 0.7Sr 0.3Mn 0.9Fe 0.1. 3 nanoparticles. A simple and convenient method for preparing the bulk nanosolids with a large number of clean interfaces has been suggested.

关键词： nanosolid pressure-induced breaking high pressure.