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

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Science china 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, china 2. School of Chemistry and Chemical Engineering, Qiqihar university, Qiqihar 1.1.06, china 3. State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin university, Changchun 1.0}023. china 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 {1. 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.

Critical slope gradient for compulsory abandonment of farmland on the hilly Loess Plateau

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Chinese Science Bulletin 1998年第5期43卷 409-412页

作者： TANG Keli+1. ZHANG Keli 1.2 and LEI Aling 1.3.1. Institute of Soil and Water Conservation, Chinese Academy of Sciences, Yangling 71.1.0,{1. 2. Department of Hydraulic Engineering, Tsinghua university, Beijing 1.0084,{1. 3. Water Resources C Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling China Department of Hydraulic Engineering Tsinghua University Beijing China Water Resources Conservation Bureau of Yangtze River Ministry of Water Resources Wuhan China

Scientific evidence for the upper limit of farmland is proposed. Shallow gully erosion is one of erosion types distributed extensively on sloping farmland in the hilly regions of the Loess Plateau. Field observation and aerial photos interpretation, as well as laboratory experiments show that the shallow gully erosion occurring on the steeper farmland in the hilly regions of the Loess Plateau is an important factor leading to intensive erosion on slope, because of its extensive distribution and intensive runoff collection. The data on the formation, development and distribution of shallow gullies on sloping farmland indicate that critical slope gradient for shallow gully initiation ranges from 1. to 20 degrees with an average of 1..2 degrees. Therefore, it is suggested that critical slope gradient for compulsory abandonment of farmland on the hilly Loess Plateau should be kept within the critical slope gradient for shallow gully initiation to prevent shallow gully formation in order to control soil loss more effectively. But as the first step, the cultivation on the slopes with slope larger than 25 degrees where the maximum erosion occurs should be strictly forbidden.

关键词： hilly region of Loess Plateau upper limitation for farmland shallow gully erosion erosion dynamic.

Two possible mechanisms for vortex self-organization

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Science china Earth Sciences 2006年第2期49卷 202-211页

作者： LUO Zhexian2, ZHOU Xiuji1.& GAO Shouting3.1. Chinese Academy of Meteorological Sciences, Beijing 1.0081.{1. 2. Department of Space Information Science, Nanjing university of Information Science and Technology, Nanjing 21.044,{1. 3. Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 1.0029,{1. 2. Department of Environmental Science Nanjing University of Information Science and Technology Nanjing 210044 China 1. Chinese Academy of Meteorological Sciences Beijing 100081 China 3. Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The vortex self-organization is investigated in this paper by four groups of numerical experiments within the framework of quasi-geostrophic model, and based on the experimental results two types of possible mechanisms for vortex self-organization are suggested. The meso-scale to-pography may enable separated vortices to merge into a larger scale vortex; and the interaction of meso-γ and meso-β scale systems may make separated vortices to self organize a typhoon-like vor-tex circulation.

关键词： vortex, self-organization, meso-scale topography, interaction of different scales.

The study on Sanmenxia annual flow forecasting in the Yellow River with mix regression model

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Science china(Technological Sciences) 2004年第z1期47卷 118-126页

作者： JIANG Xiaohui1. LIU Changming1.2, WANG Yu3.& WANG Hongrui1.1. Beijing Normal {1., Beijing 1.0875, china 2. Institute of Geographic Science and Natural Resources, Chinese Academy of Sciences, Beijing 1.01.1. china 3. Reconnaissance, Planning, Design and Research Institute, YRCC, Zhengzhou 450003. china Beijing Normal Univ Beijing 100875 Peoples R China Chinese Acad Sci Inst Geog Sci & Nat Resources Beijing 100101 Peoples R China YRCC Reconnaissance Planning Design & Res Inst Zhengzhou 450003 Peoples R China

This paper established mix regression model for simulating annual flow, in which annual runoff is auto-regression factor, precipitation, air temperature and water consumption are regression factors; we adopted 9 hypothesis climate change schemes to forecast the change of annual flow of Sanmenxia Station. The results show : (1. When temperature is steady, the average annual runoff will increase by 8.3. if precipitation increases by 1.%; when precipitation decreases by 1.%, the average annual runoff will decrease by 8.2%; when precipitation is steady, the average annual runoff will decrease by 2.4% if temperature increases 1.; if temperature decreases 1., runoff will increase by 1.2%. The mix regression model can well simulate annual runoff. (2) As to 9 different temperature and precipitation scenarios, scenario 9 is the most adverse to the runoff of Sanmenxia Station of Yellow River; i.e. temperature increases 1. and precipitation decreases by 1.%. Under this condition, the simulated average annual runoff decreases by 1..8%. On the contrary, scenario 1.is the best to the enhancement of runoff; i.e. when temperature decreases 1.℃ precipitation will increase by 1.%, which will make the annual runoff of Sanmenxia increase by 1..6%.

关键词： forecast annual flow, mix regression model, Sanmenxia Station

Anatexis in Himalayan crust:Evidence from geochemical and chronological investigations of Higher Himalayan Crystallines

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Science china Earth Sciences 2005年第9期48卷 1347-1356页

作者： YANG Xiaosong1. JIN Zhenmin2 & MA Jin1.1. State Key Laboratory of Earthquake Dynamics, Institute of Geology, china Earthquake Administration, Beijing 1.0029, china 2. Faculty of Earth Sciences, china {3. of geosciences, Wuhan 43.074, china 1. State Key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration 100029 Beijing China 2. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China

Migmatization in Higher Himalayan Crystallines (HHC) results from anatexis. The widely distributed migmatites in HHC are an important clue to investigate the relationship be- tween anatexis and the origins of Higher Himalayan leucogranites (HHL), and to understand the effect of anatexis on crustal evolution during the post-collision period. We studied in detail the chemical features of three basic constituent parts of the migmatites, i.e. leucosome, mesosome and melanosome, and determined the K-Ar ages of leucosomes. Our studies indicate that type-I leucosome is the product of crystallization of melt generated by partial melting of mesosome at source region, but type-II leucosome and HHL probably underwent crystallization differentiation of plagioclase during melt aggregation and migration. The age of 22.67 Ma of Type-I leucosome, which is a little older than the beginning of MCT movement, indicates that anatexis may have played an important role in the formation of MCT. That the ages of type-II leucosome (ranging from 1..82 to 1..3. Ma) are consistent with that of HHL provides new chronological evidence for the relationship between migmatization and HHL. We obtained a very young age of 6.23.Ma of Type-II leucosome that provides new time constraint on magma activity in the central segment of Higher Himalayas.

关键词： Higher Himalayan Crystallines, migmatite, anatexis, leucosome, K-Ar age.

Some properties on multivariate filter banks with a matrix factorization

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Progress in Natural Science:Materials International 2005年第2期15卷 20-30页

作者： LIAN Qiaofang1. XIAO Hongying2* and CHEN Qiuhui3.1. Department of Mathematics, Beijing Jiaotong {1., Beijing 1.0044, china 2. Institute of Mathematics, Academy of Mathematics and System Sciences, Chinese Academy of Sciences, Beijing 1.0080, china 3. Department of Scientific Computing and Computer Applications, Zhongshan {1., Guangzhou 51.275, china) Department of Mathematics Beijing Jiaotong University Beijing 100044 China. Institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China. Department of Scientific Computing and Computer Applications Zhongshan University Guangzhou 510275 China

A class of multivariate filter banks with a matrix factorization has been developed by Chen et al. The main purpose of this paper is to discuss some further properties of this kind of filter bank, such as the completeness, accuracy of the corresponding scaling functions and the relationships with Daubechies' wavelets and the multi-wavelets provided by Chui and Lian. Moreover, some examples are given to show that this kind of filter bank has a higher accuracy for the scaling functions.

关键词： filter banks completeness accuracy matrix factorization

Archean relic body at lower crust in Sulu area:Evidence from magnetic data

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Chinese Science Bulletin 2003年第6期48卷 589-593页

作者： WU Qifan1.2, LU Fengxiang3. LIU Qingsheng3. ZHENG Jianping3. WANG Maoji2 & WU Wenli4 1. Department of Engineering Physics, Tsinghua university, Beijing 1.0084, china 2. Aero Geophysical Survey & Remote Sensing Center, Beijing 1.0083, china 3. china university of geosciences, Wuhan 43.074, china 4. Institute of Geophysical & Geochemical Exploration, Langfang 065000, china Aero Geophysical Survey & Remote Sensing Center Beijing 100083 China china {1. of geosciences Wuhan 430074 China Institute of Geophysical & Geochemical Exploration Langfang 065000 China Department of Engineering Physics Tsinghua University Beijing 100084 China

After the new 1.1.00000 aero magnetic data were processed and the three-dimensional inversion work was carried out, a vast high magnetic body northwestward was discovered. The magnetic body is located at the depth of about 20 km on the west side of Tanlu fault and at about 25 km on the east side of Tanlu fault beneath the Sulu area. There is a difference of vertical distance of 3.5 km in depth between both sides. We think that the magnetic body is an Archean metamorphic plate and belongs to the North{1. block. The discovery of the magnetic body is significant for us to reconstruct the structure model of the Sulu orogenic belt, delineate the suture of collision between the North{1. block and the Yangtze block, and estimate the depth of slipping surface when the eastside of Tanlu fault moved northward.

关键词：苏鲁地区地壳下层太古代残余体地球物理调查区域性磁场三维反演苏鲁造山带郯鲁断裂带大别-苏鲁超高压变质带

Timing and geochemical characters of the Sanchazi magmatic arc in Mianlüe tectonic zone,South Qinling

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Science china Earth Sciences 2004年第4期47卷 317-328页

作者： LI Shuguang1. HOU Zhenhui1. YANG Yongcheng2, SUN Weidong1.1., ZHANG Guowei3. & LI Qiuli1.1. School of Earth and Space Sciences,{1. of Science and Technology of china ,Hefei 23.026,china 2. Regional Geological Survey Team of Shaanxi Province,Xianyang 71.000, china 3. Department of Geology, Northwest {1.,Xi抋n 71.069, china Present address: Max-Planck-Institut f. Chemie Postfach 3060 55020 Mainz Germany School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China Regional Geological Survey Team of Shaanxi Province Xianyang 712000 China Department of Geology Northwest University Xi’an 710069 China

The Sanchazi mafic-ultramafic complex in Mianlüe tectonic zone,South Qinling can be subdivided into two blocks,*** paleo-magmatic arc and Zhuangkegou paleo-oceanic crust fragment (ophiolite).The Sanchazi paleo-magmatic arc is mainly composed of ande-site,basaltic and basalt-andesitic gabbro(or diorite),andesitic dyke,plagiogranite and minor ul-tramafric rocks,which have typical geochemical features of island arc volcanic rocks,such as high field strength element(***,Ti)depletions and lower Cr,Ni *** Light rare earth element (LREE) and K enrichments of these rocks and zircon xenocrystals of 900 Ma from plagiogranite suggest that this magmatic arc was developed on the South active continental margin of the South Qinling *** U-Pb age of (3.0±61. Ma for zircons from plagiogranite in-dicates that the Mianlüe paleo-oceanic crust was probably subducted underneath the South Qinling micro-continent in *** is consistent with the formation time (3.9Ma) of the Huwan eclogite originating form oceanic subduction in Dabie Mountains,suggesting that the Mianlüe paleo-ocean probably extended eastward to the Dabie Mountains in *** high-Mg adakitic rocks in Sanchazi paleo-magmatic arc suggest thet the subducted oceanic crust was relatively young (<25Ma) and hot.

关键词： Qinling orogen, magmatic arc, U-Pb zircon age, ophiolite complex.

Mining subsidence control by solid backfilling under buildings

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中国有色金属学会会刊：英文版 2011年第S3期21卷 670-674页

作者： ZHA Jian-feng1. 2, 3. GUO Guang-li1. 2, FENG Wen-kai3. WANG Qiang1. 2 1. Key Laboratory for Land Environment and Disaster Monitoring of the State Bureau of Surveying and Mapping, china university of Mining and Technology, Xuzhou 221.1., china 2. Jiangsu Key Laboratory of Resources and Environmental Information Engineering, china university of Mining and Technology, Xuzhou 221.1., china 3. State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu university of Technology, Chengdu 61.059, china [a] Key Laboratory for Land Environment and Disaster Monitoring of the State Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China [b] Jiangsu Key Laboratory of Resources and Environmental Information Engineering China University of Mining and Technology Xuzhou 221116 China [c] State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China

Solid backfilling mining can reduce the buildings' damage caused by mining greatly. The reduction of subsidence value, the slow advancing speed and the subsidence caused by backfilling body compaction are the main reasons that solid backfilling mining velocity decreases significantly. Based on the research of mechanism, some principles on subsidence control of solid backfilling mining under buildings were proposed. The equivalent mining height was designed according to the fortification criteria of buildings and their attachment structures, which enables the ground movement and deformation caused by mining to be less than the corresponding fortification criteria.

关键词： solid backfilling mining subsidence control mining under buildings