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Potential energy surfaces for low-lying electronic states of SO_2

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Science china Chemistry 2006年第4期49卷 289-295页

作者： LI Anyang1, SUO Bing2. WEN Zhenyi2.& WANG Yubin2.1. Shanxi Key Laboratory of Physico-inorganic Chemistry, Department of Chemistry, northwest university, xi’an 710069,{2. 2. Institute of Modern Physics, northwest university, xi’an 710069,{2. 1. Shanxi Key Laboratory of Physico-inorganic Chemistry Department of Chemistry Northwest University Xi’an 710069 China 2. Institute of Modern Physics Northwest University Xi’an 710069 China

The potential energy surfaces for the nine low-lying electronic states of SO2.have been constructed by using the multi-reference second order perturbation theory (MRPT2. with the basis set cc-pVTZ. The optimized geometries and the adiabatic excitation energies of these states are in good agreement with experiments and previous calculations. The crossings and avoided crossings dis- played in the potential energy surfaces are expounded.

关键词： cross of PES, MRPT2. SO2 (sulfur dioxide).

Northernmost paleo-tethyan oceanic basin in Tibet:Geo-chronological evidence from ^(40)Ar/^(39)Ar age dating of Dur'ngoi ophiolite

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Chinese Science Bulletin 2001年第14期46卷 1203-1205页

作者： CHEN Liang, SUN Yong, PEI xianzhi, GAO Ming, FENG Tao, ZHANG Zhongqing & CHEN Wen1. Laboratory of Continental Dynamics, northwest university, xi’an 710069,{2. 2. Department of geology, northwest university, xi’an, 710069,{2. 3. Institute of geology, Chinese Academy of Geological Sciences, Beijing, 100037,{2. Laboratory of Continental Dynamics Northwest University Xi’an China Department of geology Northwest University Xi’an China Institute of geology Chinese Academy of Geological Sciences Beijing China

Whole rock 40Ar/39Ar age dating has been conducted on a basalt sample from Dur’ngoi ophiolite, Qinghai Province, which was reported to be the northernmost pa-leo-tethyan oceanic basin in Tibet. A high temperature pla-teau age (345.3±7.9 Ma) with an isochorn age (336.6±7.1 Ma) has been obtained, representing the eruption time of oceanic crust Considering related geological settings, the new age provides constraints on the northernmost pa-leo-tethyan suture zone in Tibet and the tectonic evolution of Paleo-tethys in Northeast Tibet and adjacent areas.

关键词： Dur’ngoi ophlolite 40Ar -39Ar age Paleo-tethys.

Discovery of bipinnatifid fronds of Protoblechnum contractum(Gu et Zhi)

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Chinese Science Bulletin 1999年第4期44卷 381-383页

作者： SUN Bainian and SHEN Guanglong Department of geology, Lanzhou university, Lanzhou 730000,{2. Department of geology, northwest university, xi’an 710069,{2. Department of geology Lanzhou University Lanzhou China Department of geology Northwest University Xi’an China

IN Permian floras of china, a dispute over the relationship among the Protoblechnum and other similar plants such as Compsopteris, Glenopteris and Supaia has been existing for a long time, and moreover it has not been completely solved up to now. Halle placed a few simple pinnate fronds from the Shihhotze Formation in the genus Protoblechnum and named them Protoblechnum Wongii Halle 70 years ago when he was studying the fossil plants from the Late Palaeozoic strata in Shanxi, china. He did not think forked or unforked fronds as an important dividing genus condition in discussing the distinction among Protoblechnum and other relative fossils. Zalessky alSO found some specimens similar to Chinese Protoblechnum while he studied the Permian fossil plants from Russia. However, he did not approve of

关键词： very over Discovery of bipinnatifid fronds of Protoblechnum contractum Gu et Zhi

A modified multi-reference second order perturbation theory

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中国科学：化学英文版 2010年第4期53卷 933-939页

作者： LI AnYang1, HAN Huixian2. SUO BingBing3, WANG YuBin3 & WEN ZhenYi3 1Institute of Computational Chemistry, Chongqing university of Post and Telecommunications, Chongqing 400065, china 2.epartment of Physics,{2., xi’ an 710069, china 3Institute of Modern Physics,{2., xi’ an 710069, china 1. Institute of Computational Chemistry Chongqing University of Post and Telecommunications Chongqing 400065 China2. Department of Physics Northwest University Xi’ an 710069 China3. Institute of Modern Physics Northwest University Xi’ an 710069 China

A new scheme with extended model space is proposed to improve the calculation of multi-reference second order perturbation theory (MRPT2.. The new scheme preserves the concise code structure of the original program, and avoids intruder states in constructions of the potential energy surface, which is confirmed by a series of comparable calculations. The new MRPT2.program is an available tool for the research of molecular excited states and electronic spectrum.

关键词： perturbation theory multi-reference intruder state

Paleoenvironments indicated by the fossil mammalian assemblages from red clay-loess sequence in the Chinese Loess Plateau since 8.0 Ma B.P.

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Science china Earth Sciences 2006年第5期49卷 518-530页

作者： XUE xiangxu1,2. ZHANG Yunxiang1,2.& YUE Leping1,2.1. State Key Laboratory of Continent Dynamics (northwest university), Institute of Cenozoic {2. and Environment, De- partment of {2., northwest university, xi’an 710069, china 2. Institute of Earth Environment, State Key Laboratory of Loess and Quaternary {2., Chinese Academy of Sciences, xi’an 710075, china 1. State Key Laboratory of Continent Dynamics (northwest university) Institute of Cenozoic Geology and Environment Department of Geology Northwest University Xi’an 710069 China 2. Institute of Earth Environment State Key Laboratory of Loess and Quaternary Geology Chinese Academy of Sciences Xi’an 710075 China

Information from eleven profiles of eolian earthy red silty clay and loess of the middle of the Late Miocene to Holocene age have been studied and correlated. A complete summary profile with projected isotopic ages and fossil-bearing beds has been assembled. The profile is subdivided into 12.stratigraphic units proceeding from the lower (older) to the upper (younger) one. The character of mammalian assemblages contained in each unit was analyzed and the corresponding pa- leo-climatic environments were deduced. The environmental character of each period and the change from the middle of the Late Miocene at about 8.0 Ma B.P. up to the Holocene progressed from the hot semiarid and semi-moist, warmer-moist, warm-moister of the Late Miocene. To slightly less warm moist, cool-dry, slight-warmer-moister of the Pliocene; later the cool to cold dry periods alternated frequently with the mild semiarid and semi-moist periods of the Quaternary. Vegetation progressed from the grasslands with sparse woods, wooded shrub-grasslands and subtropical forest-grasslands of the Late Miocene age to sparse grasslands and dry grasslands of the Pliocene; and to sparse grasslands, dry grasslands and tundras of the Quaternary. The climate changes in the Neogene were of low-amplitute in a generally warm-humid background. Those of the Quaternary were of higher am- plitude with a longer phase. Cool or cold dry and slightly warm semiarid and semi-moist climates al- ternated on a generally cool-dry background. The tendency since the start of the Quaternary was the change to more northern and western shift in the Loess Plateau, with progressively cooler and dryer conditions. The dramatic uplift of the Qinghai-xizang (Tibet) Plateau and the forming and expansion of the Arctic ice sheet might be the main reasons of the more pronounced changes in the Quaternary.

关键词： paleoenvironment, mammalian fossils, eolian red clay-loess sequence, Loess Plateau.

Synthesis of GoldMag particles with assembled structure and their applications in immunoassay

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Science china Chemistry 2006年第6期49卷 534-540页

作者： CUI Yali1, ZHANG Lianying1, SU Jing1, ZHANG Caifeng3, LI Qi2. CUI Ting3, JIN Boquan2.& CHEN Chao1,3 1. Biochip Research and Development Center, northwest university (National Engineering Research Center for Miniaturized Detection System), xi’an 710069,{2. 2. Department of Immunology, The Fourth Military Medical university, xi’an 710032.{2. 3. Shaanxi Lifegen Co., Ltd., xi’an 710069,{2. 1. Biochip Research and Development Center Northwest University (National Engineering Research Center for Miniaturized Detection System) Xi’an 710069 China 3. Shaanxi Lifegen Co. Ltd. Xi’an 710069 China 2. Department of Immunology The Fourth Military Medical University Xi’an 710032 China

Micrometer-sized Fe3O4 particles and nano-sized gold particles were first synthesized by methods of self-aggregation of surface-chemically modified Fe3O4 nanoparticles and citrate reduction of the Au3+ to Au0, respectively. Interaction between these two types of particles resulted in the assembly of nano-sized gold particles on the surface of the micrometer-sized Fe3O4 particles, forming an assembled structure with the Fe3O4 core particles around which are attached nano-sized gold parti- cles. The Fe3O4/Au structure is named GoldMag particles with assembled structure. The synthetic process, structure, and magnetic property of the GoldMag particles were analyzed. GoldMag particles with assembled structure have an irregular shape, rough surface with a diameter of 2.3 μm. These particles exhibit the superparamagnetic property with saturated magnetization of 41 A·m2.kg. In a single step, antibodies could be readily immobilized onto the surface of the particles with a high binding capacity. The GoldMag particles can be used as a novel carrier in immunoassays. The maximum quantity of human IgG immobilized onto GoldMag particles was 330 μg/mg. In order to validate the quality of the GoldMag particles as immunoassay carriers, an immunoassay system was used. The relative amount of immobilized human IgG was measured by HRP-labeled anti human IgG. The coefficient of variation within parallel samples of each group was below 6% and the coefficient of variation of means between five groups carried out separately was below 7%. Based on the sandwich method, the Hepatitis B surface antigen (HBsAg) and interleukin-8 (IL-8) were also analyzed by qualitative and quantitative detection, respectively. The result indicated that the GoldMag particles with assembled structure were an ideal carrier in immunoassay.

关键词： GoldMag particles with assembled structure, synthesis, carrier, immunoassay.

Synthesis,crystal structure and thermal behavior of Rb(NTO)·H_2.

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Chinese Science Bulletin 2001年第1期46卷 45-49页

作者： HU Mancheng, GAO Shiyang, LIU Zhihong, SONG Jirong, xiA Shuping & YU Kaibei1. Institute of Applied Chemistry, Shaanxi Normal university, xi’an 710062. china 2. Department of Chemical Engineering,{2., xi’an 710069, china 3. Chengdu Branch of Chinese Academy of Sciences, Chengdu 610041, china Institute of Applied Chemistry Shaanxi Normal University Xi’an China Department of Chemical Engineering Northwest University Xi’an China Chengdu Branch of Chinese Academy of Sciences Chengdu China

The Rb(NTO) .H2. crystal has been synthesized by reaction of 3-nitro-l,2.4-triazole-5-one (NTO) with Rb2.O3 in aqueous solution. Its crystal structure has been determined. The crystal belongs to monoclinic system. Crystal structure data: space group P2./ n; a = 0.633 0(1), b = 0.82. 1(2., c =1.2.6 4(3) nm; β = 97.90(1)°; V = 0.669 9 (2. nm3, Z = 4, Dc= 2.306 g/cm3,μ = 7.365 nm-1, F(000) = 448. An eight coordinated compound is formed between Rb+ with oxygen atoms and nitrogen atoms. A layer structure is formed by coordination bonds and hydrogen bonds. The thermal decomposition mechanism of this coordination compound is discussed.

关键词： Rb-NTO coordination compound crystal structrue thermal decomposition.

TECTONIC SIGNIFICANCE OF THE WEST KUNLUN FOLD-THRUST-BELT AND THE TARIM SOUTHWEST DEPRESSION

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地学前缘 2000年第S1期7卷 84-86页

作者： Luo Jinhai (Department of geology, northwest university, xi′an {2.,china)

The evolution of the Tarim southwest depression lying at the piedmont of the West Kunlun orogen differs completely from the evolution of the main part of Tarim basin after Later Palaeozoic because the former strongly subsides many times.. Subsidence is related closely to the West Kunlun fold thrust\|belt, thus the evolution of the Depression and the fold\|thrust\|belt reflects clearly the formation and evolution of the West Kunlun and even the Tibet.1 Evolution of the West Kunlun fold\|thrust\|belt\;Thrusting of the fold\|thrust\|belt can be classified into three stages:(1) Devonian thrusting:This is the oldest thrusting distinguished in the northern margin of the West Kunlun while the Silurian—Devonian thrusting was discriminated a few years ago by seismic data in the northern part of the East Kunlun. The Devonian thrusting is proved by the Upper Devonian dynamometamorphic rocks outcropping at the core of the anticline in the Sangzhu lying at the fold\|thrust\|belt. The rocks consist of slightly metamorphic clastic rock and have always been regarded as the Mid\|Proterozoic strata. But they are actually Upper Devonian strata according to the amount of perfect plant fossils that we found recently in the metamorphic rock, and they are overburdened `with an angular unconformity by another reliable Upper\|Devonian conglomerate in the core of the Aqike anticline. A possible explanation for this and its limited lined distribution parallel to the West Kunlun orogen is that they are subjected to metamorphism during the Later Devonian thrusting.

关键词： evolution West Kunlun fold\|thrust\|belt Tarim southw est depression correspondence

Hydrogen isotopic characteristics and their genetic relationships for individual n-alkanes in plants and sediments from Zoigê marsh sedimentary environment

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Science china Earth Sciences 2010年第9期53卷 1329-1334页

作者： DUAN Yi1, ZHENG ChaoYang2.& WU Baoxiang1 1 Key Laboratory of Petroleum Resources Research, Institute of geology and Geophysics, Chinese Academy of Sciences, Lanzhou 730000, china 2.Department of geology, northwest university, xi’an 710069, china 1. Key Laboratory of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China2. Department of Geology Northwest University Xi’an 710069 China

To understand internal relations of their hydrogen isotopic compositions in typical marsh environment, we, using GC-IRMS analytical technique, measured the hydrogen isotopes of individual n-alkanes in the herbaceous plant, woody plant leaf, and sediments from Zoigê marsh in china. The results show significant differences in the hydrogen isotopic compositions of n-alkanes among the different kinds of plants and the different species in the same kind. δD values of n-alkanes in the herbaceous plants (from -2.4‰ to -184‰) are lighter than those in woody plant leaf ( from -195‰ to -142. ), and the hydrogen isotopic compositions of n-alkanes in K. tibetica P. are lighter than P. pratensis L. The mean δD values of n-alkanes in the sediments from Zoigê marsh reflect that they were derived from herbaceous plants, which is consistent with the peat samples being composed mainly of herbaceous plant remnants. The significant differences in hydrogen isotopic compositions of n-alkanes among the sedimentary samples are caused possibly by environment factors and the difference in input quantity of different herbaceous plants. A certain negative correlation exists between the δ13C and δD values of n-alkanes in the samples, and plant types can be distinguished using the cross plot of δD vs. δ13C values of n-alkanes in the plants. These data and recognitions provide scientific basis for hydrogen isotopic applied research of individual n-alkanes.

关键词： marsh environment plants sediments individual lipids hydrogen isotopes genetic relationship