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Mesozoic-Cenozoic tectonic transition in Kuqa Depression-Tianshan,Northwest china:Evidence from sandstone detrital and geochemical records

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science{1. Earth sciences 2005年第9期48卷 1387-1402页

作者： LI Zhong1. GUO Hong2, WANG Daoxuan3.& LIN Wei1.1. {1. of Geology and Geophysics, Chinese Academy of {1.s, Beijing 1.0029, china 2. Tarim Oilfield Branch, CNPC, Korla 841.00, china 3. Hefei University of Industry, Tunxilu 1.3. Hefei 23.009, china 1. institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing Chin 2. Tarim Oilfield Branch CNPC 841000 Korla China 3. Hefei University of Industry Tunxilu 193 230009 Hefei Chin

Similar to compositional evolution of sandstone modes and detrital heavy minerals from different profiles in the Kuqa Depression, Northwest china, major element analysis of whole sandstones from the same profiles shows four discontinuous depositional interfaces or periods, respectively corresponding to Lower Triassic\Middle Triassic, Upper Jurassic\Lower Cretaceous, Lower Cretaceous\Paleogene and Miocene\Pliocene, and indicates five-phase evolution during Mesozoic-Cenozoic: (1. From the first to fifth phase, a depositional suite changes from maroon and coarse clastic, through grey-dark grey and fine, red and coarse, red-mottled, interlayered by gypsum, to brown and coarse clastic assemblages, accompanying detrital component evolution in unstable-stable-unstable-very unstable-very unstable assem- blages. It is indicated that carbonate and complex detritus gradually dominate in sandstones in post-Late Jurassic, with rapid reduction of compositional maturity. (2) For major element geo- chemical parameters of whole sandstones, CaO and Fe2 O * {1.MgO contents show a change sequence in high-low-high-higher-highest values, with rapid increasing in post-Late Jurassic. ({1. Contra some aggregative indicators for weathering indexes of sandstone detrital component, Al2O{1.(CaO+Na2O) and ln(Q/(L+CE)), show a change sequence in low-high-low-lower-lowest ratios, with rapid decreasing in post-Late Jurassic. It is found that sandstone samples of the first, second and later three phases may be distinguished from the A-CN-K and A-CNK-FM diagrams respectively. Therefore, in the Kuqa Depression-Tianshan, the most important discontinuous depositional interface recording paleotectonic and paleoclimatic transition occurred in Early Triassic\Middle Triassic and Late Jurassic\Early Cretaceous, respectively, and, however, tec- tonic differentiations of basin-range system finally result in distinct depositional systems but similar detrital weathering indexes across the Lower Cretaceous\Paleogene

关键词： Tianshan, Kuqa Depression, basin-range, depositional record, tectonic transition, Mesozoic-Cenozoic.

Optimal power allocation for cognitive relay networks: amplify-and-forward versus selection relay

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science{1.(Information sciences) 2011年第4期54卷 861-872页

作者： YUE WenJing 1.2,ZHENG BaoYu 1.2,MENG QingMin 1.YUE WenJie 3.& CUI JingWu 1.1.{1. of Signal Processing and Transmission,{1. University of Posts and Telecommunications,{1. 21.003.{3. 2 Department of Electronic Engineering,Shanghai Jiaotong University,Shanghai 200240,{3. 3.Shanxi {1. of Educational science,Taiyuan 03.009,{3. 1. institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China2. Department of Electronic Engineering Shanghai Jiaotong University Shanghai 200240 China3. Shanxi Institute of Educational Science Taiyuan 030009 China

We consider a cognitive relay network which is defined by a source,a destination,and cognitive relay nodes and primary user *** this network,a source is assisted by cognitive relay nodes which allow coexisting with primary user nodes by imposing severe constraints on the transmission power so that they operate below the noise floor of primary user *** this paper,we mainly study the power allocation strategies of this system to minimize the outage probability subject to total and individual power constraints for cognitive relay nodes and subject to interference constraints for primary user nodes.A relay transmission scheme,namely amplify-and-forward (AF),is *** first present an optimal power allocation (OPA) scheme to minimize the system outage probability,based on instantaneous channel state information among the source,destination and relay nodes and mean channel gains between primary user nodes and cognitive ***,we propose a selection AF scheme (S-AF) where the single best relay is chosen to assist in the transmission and study power allocation strategy for S-AF to minimize outage *** analytical power allocation strategies have been validated through numerical *** results indicate that the AF with OPA and S-AF with OPA have significantly better outage behavior and average throughput than AF and S-AF schemes *** also find that S-AF with OPA achieves a higher throughput,and hence lower outage probability than AF with OPA.

关键词： cognitive radio (CR) relay networks power allocation outage probability

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. Department of Physics, Jilin University, Changchun 1.0}023. china 2. Changchun {1. of Physics, Chinese Academy of sciences, Changchun 1.0}021. china 3. {1. of Metal R Department of Physics 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 0.3.n 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 3.%. This kind of breaking has a close relation to the existence of oxygen deficiency in La 0.7Sr 0.3.n 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.

Structural properties of GaN(0001. epitaxial layers revealed by high resolution X-ray diffraction

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science{1.(Physics,Mechanics & Astronomy) 2010年第1期53卷 68-71页

作者： XIE ZiLi 1,2,3. ZHOU YuanJun 1 , SONG LiHong 1,2 , LIU Bin 1 , HUA XueMei 1,2 , Xiu XiangQian 1 , ZHANG Rong 1,2,3.& ZHENG YouDou 1,2,3.1 JiangSu Provincial Key Laboratory of Advanced Photonic and Electronic Materials and Department of Physics, nanjing University, nanjing 210093. china 2 nanjing National Laboratory of Microstructures, nanjing 210093. china 3.NJU-Yangzhou institute of Opto-electronics, Yangzhou, 225001, china 1. JiangSu Provincial Key Laboratory of Advanced Photonic and Electronic Materials and Department of Physics Nanjing University Nanjing 210093 China2. Nanjing National Laboratory of Microstructures Nanjing 210093 China3. NJU-Yangzhou Institute of Opto-electronics Yangzhou 225001 China

High-resolution X-ray diffraction has been used to analyze GaN(0001. epitaxial layers on sapphire substrates. Several structural properties of GaN, including the lattice constants, strains, and dislocation densities are revealed by the technique of X-ray dffraction (XRD). Lattice constants calculated from the omega/2theta scan are c=0.51.5 nm and a=0.3.57 nm. Also, the in-plane strain is -1.003., while out of the plane, the epitaxial film is almost relaxed. Several methods are used to deduce the mosaicity and dislocation density of GaN, showing that the edge type dislocations are the overwhelming majority.

关键词： GaN XRD dislocation epitaxial

Re-Os(ICP-MS)dating of the massive sulfide ores from the Jinchuan Ni-Cu-PGE deposit

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science{1. Earth sciences 2005年第10期48卷 1672-1677页

作者： YANG Gang1.2, DU Andao1. LU Jiren3. QU Wenjun1.& CHEN Jiangfeng2 1. National Research Center of Geoanalysis, Beijing 1.003., china 2. Laboratory for Earth Material Cycling, School of Earth and Space {1.s, University of {1. and Technology of china, Hefei 23.026, china 3. institute of Mineral Resource, Chinese Academy of Geological {1.s, Beijing 1.003., china National Research Center of Geoanalysis Beijing china Laboratory for Earth Material Cycling School of Earth and Space Sciences University of Science and Technology of China Hefei China institute of Mineral Resource Chinese Academy of Geological {1.s Beijing china

Massive sulfide ore from the Jinchuan Ni-Cu-PGE deposit was dated by Re-Os technique using Carius Tube digestion, Os distillation, Re extraction by acetone and ICP-MS measurement. An isochron giving an age of 83. ± 3. Ma, initial 1.7Os/1.8Os ratio of 0.279 ± 0.01. (MSWD = 1.7) and γOs = 1.0} ± 1. is obtained. The Re-Os age obtained agrees, within analytical uncertainties, with previous SHRIMP zircon U-Pb age of 827 ± 8 Ma (n=5, MSWD = 4.3.. The result suggests that the deposit was formed at Neoproterozoic and that the formation of the Jinchuan Ni-Cu-PGE sulfide deposit may be closely related to the plume activity, which were attributed to the breakup of the Rodinia supercontinent. The high γOs of the massive ores sug-gests that crustal material was involved in the formation of the Jinchuan deposit, however, the quantity of the added crustal material is less than 1.%.

关键词： Jinchuan Ni-Cu-PGE deposit, Re-Os dating, ICP-MS.

Structures and stability of isomers of[C,N,N,P]system

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science{1. Chemistry 2005年第5期48卷 415-423页

作者： KAN Wei1.2, ZHONG Hua1. YU Haitao1. FU Honggang1.3.& SUN Jiazhong1.3.1. School of Chemistry and Materials science, Heilongjiang University, Harbin 1.0080,{1. 2. School of Chemistry and Chemical Engineering, Qiqihar University, Qiqihar 1.1.06,{1. 3. State Key Laboratory of Theoretical and Computational Chemistry, {3. of Theoretical Chemistry, Jilin University, Changchun 1.0}023.{1. 1. School of Chemistry and Materials science Heilongjiang University 150080 Harbin China 2. School of Chemistry and Chemical Engineering Qiqihar University 161006 Qiqihar China 3. Jilin University State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry 130023 Changchun China

Nine isomers, twenty transition states, and some relative dissociation fragments of [C,N,N,P] system were located at the B3.YP/6-3.1.(d) and QCISD(t)/6-3.1.G(2df) (single-point) levels of theory, and the isomerization, structures, and stability of these obtained isomers were suggested. The results indicate that four nonlinear chainlike isomers NCNP, NCPN, CNPN, and CNNP with 2A′ electronic state are kinetically stable. Other isomers are kinetically unstable to-wards isomerization or dissociation because of the corresponding smaller reaction barriers. Furthermore, calculated vibrational frequencies, rotational constants, dipole moments, the first adiabatic ionization energies, and adiabatic electron affinities of the four isomers may provide some theoretical information that is helpful for identifying their existence in future laboratory and interstellar investigations. The results are also compared with [Si,N,N,P] system.

关键词： potential energy surface, [C,N,N,P] system, isomerization, kinetic stability.

SOTER-Based soil Water Erosion Simulation in Hainan Island

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Pedosphere 2003年第2期13卷 139-146页

作者： ZHAO YUGUO, ZHANG GANLIN and GONG ZITONGinstitute of {1. science, the Chinese Academy of sciences, nanjing 21.008 (china) institute of {1. science the Chinese Academy of Sciences Nanjing 210008 (China)

The actual and potential water erosion rates of soils with different landcovers in Hainan Island,{1., were estimated based on the universal soil loss equation (USLE) anda 1.200000 soils and Terrain Digital Database (SOTER) database, from which soil water erosionfactors could be extracted. 92.8% of the whole island had a current erosion rate of lower than 500 tkm^(-2) a^(-1.. soil erosion risk was considered to be high because of its abundant *** vegetation cover, the potential soil erosion rate would be extremely high and 90.8% of theisland would have a soil erosion rate higher than 2500 t km^(-2) a^(-1.. Relative erosionvulnerability of different soil zones, landform types, and lithological regions of the island wascompared by introducing a relative erosion hazard parameter a. Cambosols developed from siltstoneand mudstone in low hill regions were pinpointed as soils with the highest erosion risk in theisland.

关键词： hainan island soil erosion risk assessment SOTER USLE

A general model for estimating actual evaporation from non-saturated surfaces

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Journal of Geographical sciences 2002年第4期12卷 479-484页

作者： QIU Xinfa1.2, ZENG Yan3. LIU Changming3.1. Dept. of Urban && Resource science, {1. University, {1. 21.093.{3. 2. Dept. of Geography, {1. institute of Meteorology, {1. 21.044,{3. 3. Inst. of Geographic sciences and Natural Resources Dept. of Urban & Resource science Nanjing University Nanjing China Dept. of Geography Nanjing Institute of Meteorology Nanjing China Inst. of Geographic sciences and Natural Resources Research CAS Beijing China

Based on energy balance equation and mass transfer equation, a general model to estimate actual evaporation from non-saturated surfaces was derived. Making use of two concepts, “relative evaporation” and “relative drying power”, a relationship was established to account for the departure from saturated conditions. Using this model, the actual evaporation (evapotranspiration) can be calculated without the need of potential evaporation estimation. Furthermore, the model requires only a few meteorological parameters that are readily and routinely obtainable at standard weather stations. Based on nearly 3. years data of 43. meteorological stations and 51. hydrological stations in china, in combined with GIS, nine typical river basins were selected. Using the data of the selected river basins, the model was tested. The results show that the actual evaporation rate can be estimated with an error of less than 1.% in most areas of china, except few years in the Yellow River Basin.

关键词： potential evaporation actual evaporation

中国政治经济学年度发展报告（2023.（下）

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政治经济学评论 2024年第3期 90+207-208页

作者： Center for Studies of Contemporary Political Economy,Research institute for 21.t-Century Marxism,Nankai University·University of Chinese Academy of Social {1. Center for Teaching and Research on Capital,Renmin University of china National institute of Socialist Political Economy with Chinese Characteristics,Renmin University of china 南开大学·中国社会科学院大学21.纪马克思主义研究院当代政治经济学研究中心中国人民大学《资本论》教学与研究中心中国人民大学全国中国特色社会主义政治经济学研究中心

编者按2023.，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，...

编者按2023.，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，取得系列代表性成果。为准确刻画学界研究进展和轨迹，推动中国经济学理论体系的构建和完善，本刊精选议题如期奉上《中国政治经济学年度发展报告（2023.》。自201.年起，本刊连续十四年发布《中国政治经济学年度发展报告》，“年度发展报告”专栏已成为本刊标志性特色栏目。2023.报告聚焦1.个专题，分为（上）（下）两篇，其中专题1.6于报告（上）篇刊登，专题7—1.由报告（下）篇刊登。2023.报告（下）选题如下：

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