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Geochemistry of the high-Mg andesites at Zhangwu, western Liaoning: Implication for delamination of newly formed lower crust

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Science china Earth Sciences 2007年第12期50卷 1773-1786页

作者： HUANG Hua1.GAO Shan1.2.HU ZhaoChu1.LIU XiaoMing2.& YUAN HongLing2.1.State Key Laboratory of Geological Processes and mineral resources,{2. University of geosciences,Wuhan 430074,{2. 2.State Key Laboratory of Continental Dynamics,Department of Geology,Northwest University,Xi’an 71.069,{2. 1. State Key Laboratory of Geological Processes and mineral {1. China University of Geosciences Wuhan 430074 China 2. State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi’an 710069 China

Ten volcanic samples at Zhangwu,western Liaoning Province,North china were selected for a sys-tematic geochemical,{1.ogical and geochronological study,which provides an opportunity to ex-plore the interaction between the continental crust and mantle beneath the north margin of the North china *** one basalt sample(SiO2. 50.2.%),the other nine samples are andesitic with SiO2.contents ranging from 53% to 59%.They have relatively high MgO(3.4%―6.1.,Mg#=50―64) and Ni and Cr contents(Ni 2.×1.?6―1.7×1.?6,Cr 51.1.?6―478×1.?6).Other geochemical characteristics of Zhangwu high-Mg andesites(HMAs) include strong fractionation of light rare earth elements(LREE) from heavy rare earth elements(HREE),and Sr from Y,with La/Yb greater than 1.,and high Sr/Y(34― 1.5).Zircons of andesite YX2.0 yield three age groups with no Precambrian age,which precludes ori-gin of the Zhangwu HMAs from the partial melting of the Precambrian *** oldest age group peaking at 2.3 Ma is interpreted to represent the collision of the Siberia block and the North china block,resulting in formation of the Central Asian orogenic belt by closure of the Mongol-Okhotsk *** intermediate age group corresponds to the basalt underplating which caused the wide-spread coeval granitoids in the North china craton with a peak 2.6Pb/2.8U age of 1.2.*** youngest age group gives a 2.6Pb/2.8U age of 1.3}±2.Ma,which is interpreted as the eruption age of the Zhangwu *** high 87Sr/86Sri(1.3} Ma)>0.706 and low εNd(t)= ?6.36―?1..99 of the Zhangwu HMAs are distinct from slab *** common presence of reversely zoned clinopyroxene phenocrysts in the Zhangwu HMAs argues against the origin of the Zhangwu HMAs either from melting of the water saturated mantle or melting of the lower *** light of the evidence mentioned above,the envisaged scenario for the formation of the Zhangwu HMAs is related to the basaltic underplating at the base of the crust,which led to the thickening of the lower crust and

关键词： Zhangwu HMAs, basalt underplating, newly formed lower crust, delamination, North china craton

Theoretical study on thermal decomposition of azoisobutyronitrile in ground state

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Science china Chemistry 2004年第5期47卷 373-380页

作者： SUN Chengke1.2. ZHAO Hongmei1.& LI Zonghe1.1. Department of Chemistry, Beijing Normal University, Beijing 1.0875,{1. 2. Department of Chemistry, Qujing Normal college, Qujing 655000,{1. 1. Department of Chemistry Beijing Normal University 100875 Beijing China 2. Department of Chemistry Qujing Normal College 655000 Qujing China

The thermal decomposition mechanisms of azoisobutyronitrile (AIBN) in the ground state have been investigated systematically. Based on the potential energy surfaces (PES) of various possible dissociation paths obtained using the semiempirical AM1.method with partial optimization, the density function theory B3LYP/6-31.G* method was employed to optimize the geometric parameters of the reactants, the intermediates, the products and the transition states, which were further confirmed by the vibrational analysis. The obtained results show that the re- action process of the two-bond (three-body) simultaneous cleavage Me2.CN)C─ N=N─ C(CN)Me2. 2.e2.CN)C?+N2.is much more favorable than the reaction process of the two one- bond asynchronous cleavage Me2.CN)CN=N─C(CN)Me2.? Me2.CN)CN=N?+ Me2.CN)C?? Me2.CN)C?+ N2. It was suggested that the electron shrinking effect of double bond (─N=N─) in AIBN and the stabilities of the Me2.CN)C?radical as well as N2.molecule are main factors of leading to the reaction proceeding in the former pathway. The calculation results were consistent with all the experimental facts.

关键词： azoisobutyronitrile, radicals, thermal decomposition, density function theory (DFT).

Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural Science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1.2.and Li Jianping2.1. college of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, china 2. LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 1.002., china) college of Atmospheric Sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 1.48—2.05. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1.76. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

Mechanism for calcite dissolution and its contribution to development of reservoir porosity and permeability in the Kela 2.gas field,Tarim Basin,{1.

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Science china Earth Sciences 2008年第4期51卷 567-578页

作者： YU BingSong1.3, DONG HailLiang2.3 & RUAN Zhuang1.3 1.State Key Laboratory of Geological Processes and {1. resources,{2. University of geosciences, Beijing 1.0083,{2. 2.Department of Geology, Miami University,Oxford, OH 45056, USA 3 Geomicrobiology Laboratory,{2. University of geosciences, Beijing, 1.0083,{2. State Key Laboratory of Geological Processes and mineral {1. China University of Geosciences Beijing 100083 China Department of Geology Miami University Oxford OH 45056 USA Geomicrobiology Laboratory China University of Geoscien

This study is undertaken to understand how calcite precipitation and dissolution contributes to depth-related changes in porosity and permeability of gas-bearing sandstone reservoirs in the Kela 2.gas field of the Tarim Basin, Northwestern{1.. Sandstone samples and pore water samples are col-lected from well KL2.1.in the Tarim Basin. Vertical profiles of porosity, permeability, pore water chem-istry, and the relative volume abundance of calcite/dolomite are constructed from 3600 to 4000 m below the ground surface within major oil and gas reservoir rocks. Porosity and permeability values are in-versely correlated with the calcite abundance, indicating that calcite dissolution and precipitation may be controlling porosity and permeability of the reservoir rocks. Pore water chemistry exhibits a sys-tematic variation from the Na2.O4 type at the shallow depth (3600-3630 m), to the NaHCO3 type at the intermediate depth (3630―3695 m),and to the CaCl2.type at the greater depth (372.―3938 m). The geochemical factors that control the calcite solubility include pH, temperature, pressure, Ca2. concen-tration, the total inorganic carbon concentration (ΣCO2., and the type of pore water. Thermodynamic phase equilibrium and mass conservation laws are applied to calculate the calcite saturation state as a function of a few key parameters. The model calculation illustrates that the calcite solubility is strongly dependent on the chemical composition of pore water, mainly the concentration difference between the total dissolved inorganic carbon and dissolved calcium concentration (i.e., [ΣCO2. -[Ca2.]). In the Na2.O4 water at the shallow depth, this index is close to 0, pore water is near the calcite solubility. Calcite does not dissolve or precipitate in significant quantities. In the NaHCO3 water at the intermedi-ate depth, this index is greater than 0, and pore water is supersaturated with respect to calcite. Massive calcite precipitation was observed at this depth interval and

关键词： calcite dissolution porosity thermodynamic Tarim Basin

Microwave peak absorption frequency of liquid

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Science china(Physics,Mechanics & Astronomy) 2008年第9期51卷 1254-1263页

作者： HAN GuangZe1.& CHEN MingDong2.1.Department of Physics,South{1. University of technology,Guangzhou 51.640,{2. 2.Guangzhou Auto college,South{1. University of technology,Guangzhou 51.800,{2. 1. Department of Physics South China University of Technology Guangzhou 510640 China 2. Guangzhou Auto {1. South China University of Technology Guangzhou 510800 China

Microwave-assisted extraction is a new effective method which has practical ap-plications in many fields. Microwave heating is one of its physical mechanisms,and it also has the characteristic of selectivity. When the applied microwave fre-quency equals a certain absorption frequency of the material (or specific compo-nent),the material will intensively absorb microwave energy. This is also known as resonant absorption,and the frequency is called the peak absorption frequency which depends on the physical structure of the material. In this work,dynamic hy-drogen bond energy was included in molecular activation energy; with the liquid cell model,the expression of interaction energy between dipolar molecules was derived. The rotational relaxation time was gotten from the Eyring viscosity formula. Then based on the relationship between dielectric dissipation coefficient and re-laxation time,the expression of microwave peak absorption frequency as a func-tion of the material physical structure,rotational inertia and electrical dipole mo-ment of molecules was established. These theoretical formulas were applied to water and benzene,and the calculated results agree fairly well with the experi-mental data. This work can not only deepen the study of the interaction between microwave and material,but also provide a possible guide for the experiment of microwave-assisted extraction.

关键词： microwave-assisted extraction microwave heating relaxation time liquid viscosity peak absorption fre-quency

Tectonic setting of the Helong Block:Implications for the northern boundary of the eastern North china Craton

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Science china Earth Sciences 2005年第10期48卷 1599-1612页

作者： ZHANG Yanbin1. WU Fuyuan1. ZHAI Mingguo1.& LU Xiaoping1.2.1. Institute of Geology and Geophysics, Chinese Academy of Sciences, P.O. Box 982., Beijing 1.002., china 2. Regional Geological and mineral {2. Survey of Jilin Province, Changchun 1.0062. china Institute of Geology and Geophysics Chinese Academy of Sciences Beijing china Regional Geological and mineral {1. Survey of Jilin Province Changchun{2.

LA-ICP-MS zircon U-Pb dating indicates that the Bailiping granitic pluton was em-placed during Late Paleozoic to Early Cretaceous (2.5―1.6 Ma) by four distinct magmatic epi-sodes, arguing against the previous thought that the Bailiping granites were emplaced during Archean, Proterozoic or Early Paleozoic. It is suggested that the so-called Archean Jincheng-dong granite-greenstone belt, mainly composed of Bailiping granites, should be broken down. Sr-Nd isotopic compositions of the Bailiping granites are similar to those of the Phanerozoic granites in the Xing’an-Mongolian orogenic belt, suggesting that their parental magmas were mainly derived from a juvenile crust with some contamination of ancient crustal materials during magma rising and/or emplacement. Therefore, the basement of the Helong Block is similar to that in the northern Xing’an-Mongolian Orogenic Belt, but different from that of the North{1. Craton. It is proposed that the Archean Jinchengdong complex in this area is probably an exotic slice from the North{1. Craton, which indicates that the Fu’erhe-Gudonghe Fault, located in northern part of the Helong area, is not the boundary between the North{1. Craton and the Xing’an-Mongolian Orogenic Belt. The possible boundary should be located further southward more than 50 km and near the Baitoushan volcano.

关键词： LA-ICPMS ziron U-Pb dating, Bailiping complex, Helong Block, North china Craton, Sr-Nd isotope.

Commission Strategy of the Auction House

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Wuhan University Journal of Natural Sciences 2006年第3期11卷 507-510页

作者： WANG Yan~ 1.2.1. {1. of Economics, Fudan University, Shanghai 2.0433, china 2. School of Mathematics and Statistics, Wuhan University , Wuhan 430072. Hubei, china college of Economics Fudan University 200433 Shanghai China School of Mathematics Statistics Wuhan University 430072 Wuhan Hubei China

In a SIPV model, when the commission proportion is not certain, but related with bargain price, generally, it is a linear function of the bargain price, this paper gives bidders＇ equilibrium bidding strategies in the first-and secondprice auctions. We find that the equilibrium strategies in second-price auction are dominant strategies. For seller or auction house, whether the fixed proportion or the unfixed proportion is good is not only related with constant item and the linear coefficient of the linear function, the size of the fixed commission proportion, but also related with the value of the item auctioned. So, in the practical auctions, the seller and the auction house negotiated with each other to decide the commission rules for their own advantage.

关键词： auction commission proportion Bayesian equilibrium bidding strategy

Diffusion and Oxidation Wear of PCBN Tool based on Thermodynamics

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Journal of Wuhan University of technology(Materials Science) 2010年第2期25卷 265-271页

作者：邵芳 Binzhou Vacational college School of Mechanical Engineering Shandong University

The rules of diffusion wear and oxidation wear for PCBN cutting tools were analyzed based on thermodynamics theory. Dissolution concentrations in typical normal workpice materials of PCBN tool material at different temperature were then calculated. Diffusion reaction rules in high temperature were developed and analyzed using the Gibbs free energy criterion. The machining tests were conducted using the PCBN tools at different cutting speeds of 50, 95,1.0 and 1.0 m/min, feed of 0.1. 0.2.and depth of cut of 0.1. 0.8, 1. and 1.5 mm respectively on a PUMA300LM numerically-controlled lathe. It was found that the theoretical results were uniform with the experimental data, and the results will provide useful references for tool material design and selection.

关键词： thermodynamics PCBN tool diffusion wear oxidation wear

Proton Conducting Composite Membranes from Sulfonated Polyether Ether Ketone and SiO_2

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Journal of Wuhan University of technology(Materials Science) 2009年第1期24卷 95-99页

作者：张高文 college of Chemistry and Environment Hubei University of Technology

Proton conducting composite membranes from sulfonated polyether ether ketone and SiO2.for direct methanol fuel cell （DMFC） application were prepared with sulfonated polyether ether ketone（SPEEK） and tetracethoxy silane（TEOS） by sol-gel method. The covalent crosslinking structure was formed between —SO3H of SPEEK via SiO2. The SEM images show that the interfacial compatibility of SPEEK and SiO2.is improved obviously and SiO2.disperses uniformly in the polymer matrix and the particle diameter of SiO2.does not exceed 40 nm. The proton conductivity of composite membranes decreases slightly compared with the SPEEK membrane while the methanol permeability and swelling of composite membrane are improved remarkablely owing to covalent cross-linking between —SO3H and SiO2..

关键词： direct methanol fuel cell sulfonated polyether ether ketone sol-gel method proton conductivity methanol permeability