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Application of backflush and micro-flow techniques to the analysis of C5—C13 hydrocarbons in crude oils and its geochemical significance

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Progress in Natural Science:Materials International 2007年第11期17卷 1382-1387页

作者： Wang Peirong1,2. Zhao Hong2.3, Xu Guanjun1,4. Zhu Cuishan2.3, Xiao Tingrong4. Zhang Min2.3 and Zhang Bin1,4.1. Key Laboratory of Petroleum Geo{4., china National Petroleum Corporation, Beijing 100083, china 2. Geo{4. department of yangtze University, jingzhou 4.4.23. china 3. Key Laboratory of Exploration Technologies for Oil and Gas Resources, Ministry of Education, yangtze University, jingzhou 4.4.23. china 4. Petroleum Geology Central Laboratory, Research Institute of Petroleum Exploration and Development, Petrochina, Beijing 100083, china) Key Laboratory of Petroleum Geochemistry China National Petroleum Corporation Beijing 100083 China Geochemistry department of {2. University Jingzhou 434023 China Key Laboratory of Exploration Technologies for Oil and Gas Resources Ministry of Education Yangtze University Jingzhou 434023 China Petroleum Geology Central Laboratory Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

An Agilent 6890N GC equipped with both FID and Agilent 5975 MSD analyzer has been employed to analyze C5—C13 hydrocarbon fractions of crude oils. A technical combination of program temperature volatilizer injection, backflush and micro-flow controller afforded a fine separation of C5—C13 compounds on a PONA column with the heavy part of crude oils being cut off before entering the analytical column. Both GC-FID chromatogram and GC-MS mass chromatograms (MID and full scan) could be obtained at the same time. The retension time differences of nC6—nC13 alkanes between GC and TIC were in the range of 0.02.0.58 minutes. Totally 2.6 peaks have been assigned group compositions. Results on 8 typical oil samples from CNPC Key Laboratory Crude Oil Library showed that the characteristics of C6—C13 hydrocarbon group composition could be used in oil-oil correlation studies.

关键词： GC analysis GC/MS analysis backflush micro-flow controller light fraction in crude oil

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Theoretical study on the reaction mechanism of(CH_3)_3CO+CO

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Science china chemistry 2005年第1期48卷 18-24页

作者： ZHAO Hongmei1,2.3, SUN Chengke1,4. ZHANG Rongchang3, XI Hongmin3 & LI Zonghe1 1. department of chemistry, Beijing Normal University, Beijing 100875, {2. 2. The Laboratory of Molecular Reaction Dynamics, Institute of chemistry, Chinese Academy of Sciences, Beijing 100080, {2. 3. department of chemistry, Beihua University, Jilin 132.13, {2. 4. department of chemistry, Qujing Normal University, Yunnan 655000, {2. 1. department of chemistry Beijing Normal University 100875 Beijing China 2. The Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences 100080 Beijing China 3. department of chemistry Beihua University 132013 Jilin China 4. department of chemistry Qujing Normal University 655000 Yunnan China

The reaction mechanism of (CH3)3CO with CO has been theoretically investigated using density-functional theory (DFT) calculations at B3LYP/6-31G* level. In order to get more reliable energy values the single-point energy is evaluated at CCSD (T)/6-31++G** level. The results show that the reaction is multi-channel and the reaction of (CH3)3CO radical with CO mostly produces (CH3)3C + CO2. The reaction could play a role in eliminating air pollution.

关键词： DFT, B3LYP, (CH3)3CO, radical.

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Study on the two and three-parameter working stability regions of 3Y-TZP suspension

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Science china(Technological Sciences) 2006年第5期49卷 547-568页

作者： CHEN Youqiang1, 2. ZHANG Xinni3, CHEN Sha’ou3 & QI Ping3 1. department of chemistry, Qingdao University, Qingdao 2.6071, {2. 2. department of chemistry, Tsinghua University, Beijing 100084. {2. 3. department of Physics, Qingdao University, Qingdao 2.6071, {2. 1. department of chemistry Qingdao University Qingdao 266071 China 2. department of chemistry Tsinghua University Beijing 100084 China 3. department of Physics Qingdao University Qingdao 266071 China

We determined the variation tendency of viscosity (η) at various solids load- ing (α) for 3Y-TZP suspension as a function of dispersant concentration (Cw) using vis- cosity measurement, measured the diameter of particles as a function of Cw in very dilute suspension using light scattering method, and obtained the surface features of the sedi- ment of suspension with different Cw using SEM. We also discussed the influence of the microstructure of adsorbed polymer layers on particles and their interactions in the dis- persing medium on the stability of suspension. Then two different stable states and two different unstable states for 3Y-TZP suspension were given. Accordingly, the (Cw, η), (Cw, α), and (α, η) two-parameter, and (Cw, α, η) three-parameter stability maps were con- structed. Based on the DLVO theory calculations, the dispersant concentration, particle distance (r), and interparticle potential energy (VT) maps with various solids loading for 3Y-TZP aqueous suspension were also constructed. In (Cw, r) two-parameter coordinate system, the stable motion region map for particles was established. The Cw, α, and VT,max (the highest potential energy) surface of the potential barrier map was obtained through calculation and simulation on the basis of the surfaces of Cw, r, VT maps introduced above. The (Cw, α) two-parameter stability map was then obtained from the Cw, α, VT,max map. The results showed that this theoretical map can qualitatively prove the experimentally obtained results—the existence of different dispersed states of particles in suspension system and the variation tendency of suspension stability with changing each parame- ter—were reasonable.

关键词： 3Y-TZP, suspension, stability, DLVO theory, interparticle potential energy.

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Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic Materials

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含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1, YANG De suo 2. ZHANG Jiao qiang 3 (1. department of chemistry,Northwest University, Xi′an 710065, {2. 2. department of chemistry and Chemical Engineering, Baoji College of Arts and Science, Baoji 72.007, {2. 3. department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.

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Syntheses,characterization,crystal structure and magnetic properties of copper(Ⅱ) α,β-unsaturated carboxylate complexes with trimethyl phosphate

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Chinese Science Bulletin 2001年第12期46卷 987-991页

作者： WANG Yaoyu, LIU Ping, SHI Qian, GAO Yici & SHI Qizhen1. department of chemistry, Northwest University, Xi’an 710069, {2. 2. department of chemistry, Wenzhou Teachers College, Wenzhou 32.003, {2. 3. department of chemistry, Lanzhou University, Lanzhou 730000, {2. department of chemistry Northwest University Xi’an China department of chemistry Wenzhou Teachers College Wenzhou China department of chemistry Lanzhou University Lanzhou China

Two ternary complexes Cu2.4.OP(OCH3)3]2.(A represents CH2.CH-COO- and CH2.C(CH3)-COO-) have been synthesized, and elemental analyses, IR, ESR, electronic reflectance spectra and magnetic studies were carried out. The single crystal X-ray diffraction shows that Cu2.CH2.C(CH3)-COO]4.OP(OCH3)3]2.is triclinic, with space group P1, a = 1.0512.(13), b = 1.7559(5), c = 1.94.79(3) nm, α =91.2.3(14.°,(β = 102.559(6)°,γ= 106.339(13)°, Z = 4.and R = 0.0668. Two copper(Ⅱ) atoms are bridged by four (a-methacrylate groups, and each copper(Ⅱ) atom is coordinated with a trimethyl phosphate molecule in the axial position, forming a distorted square pyramidal configuration. The symmetric center is between the two copper(Ⅱ) atoms, and the Cu-Cu bond distance is 0.2.098(6) nm. The Cu-Cu distance and magnetic studies suggest that there exist anti-ferromagnetic interactions between the two copper(Ⅱ) atoms.

关键词： copper(Ⅱ ) complex α β-unsaturated carboxylate trimethyl phosphate magnetic property crystal structure.

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Density functional study on enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine

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Science china chemistry 2006年第4期49卷 296-307页

作者： LI Ming1, ZHENG Wenxu2.& TIAN Anmin2.1. department of chemistry, Southwest-{2. Normal University, Chongqing 4.0715, {2. 2. department of chemistry, Sichuan University, Chengdu 610064. {2. 1. department of chemistry Southwest-China Normal University Chongqing 400715 China 2. department of chemistry Sichuan University Chengdu 610064 China

The enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine is discussed by the density functional theory (DFT) method. The main intermediates and transition states for this reaction are optimized completely at the B3LYP/6-31g(d) level, and the transition states are verified by vibrational modes. As shown, the chirality-controlled steps for this re- action are the hydride transfer from borane to carbonyl carbon and oxime carbon of keto oxime ether, and the chirality for the reduced products is determined in these two reaction steps. In all examined reaction paths, the first hydride is transferred via a six-membered ring and the second hydride via a five-membered ring or a four-membered ring.

关键词： keto oxime ether, oxazaborolidine, enantioselective reduction, DFT.

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Sorption of Eu^(3+) onto nano-size silica-water interfaces

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Science china Earth Sciences 2005年第11期48卷 1942-1948页

作者： HU Ping1,2. YIN Xiulan3 , ZHAO Linghu1 & LI Dien4.1. department of Earth Sciences, china University of Geosciences, Wuhan 4.0074. china 2. Northeastern Illinois University, Chicago, IL 6062., USA 3. china Institute of Geo-Environmental Monitoring, Beijing 100081, china 4. Division of chemistry, Los Alamos National Laboratory, Los Alamos, NM 8754., USA 1. department of Earth Sciences China University of Geosciences 430074 Wuhan China 2. Northeastern Illinois University 60625 Chicago IL USA 3. china Institute of Geo-Environmental Monitoring 100081 Beijing China 4. Division of chemistry Los Alamos National Laboratory 87544 Los Alamos NM USA

The sorption of Eu species onto nano-size silica-water interfaces is investigated at pH range of 1―8.5 and the initial Eu concentrations (CEu) of 2.× 10?5, 2.× 10?4.and 2.× 10?3 M using fluorescence spectroscopy. The sorption rate of Eu is initially low, but significantly in-creases at pH > 4. For the initial CEu of 2.× 10?5, 2.× 10?4.and 2.× 10?3 M, the dissolved Eu spe-cies are completely sorbed onto silica-water interfaces at pH = 4.75, ~5.8 and 6.6, respectively, with the respective sorption densities of ~1.58 × 10?8, 1.58 × 10?7 and 1.58 × 10?6 mol/m2. The sorbed Eu species at pH 3+, which is sorbed onto silica-water interfaces as an outer-sphere complex at pH 2. to ~6 at pH = 6. At pH = 6 – 8, Eu(OH)2., Eu(CO3)+ and Eu(CO3)2. form in the solutions, and Eu(CO3)+ is dominant at pH = ~7.5. These ions may be sorbed onto silica-water interfaces as inner-sphere bidentate complexes or multi-nuclear pre-cipitates.

关键词： surface sorption, Eu3+ species, nano-size silica, fluorescence spectroscopy, immobilization of toxic metals

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Regioselective aminohalogenation of β-nitrostyrenes using NCS and NBS as nitrogen/halogen sources

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Science china chemistry 2010年第1期53卷 140-146页

作者： ZHI SanJun1,2.SUN Hao2.LIN Chen2.ZHANG GuangQian2.LI GuiGen4.& PAN Yi2.3 1 department of chemistry,Huaiyin Normal University,Huai’an 2.1003,{2. 2.School of chemistry and Chemical Engineering,Nanjing University,Nanjing 2.0093,{2. 3 State Key Lab of Coordination chemistry,Nanjing University,Nanjing 2.0093,{2. 4.department of chemistry and Biochemistry,Texas Tech University,Lubbock,Texas 794.9-1061,USA 1. department of chemistry Huaiyin Normal University Huai’an 221003 China2. School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China4. Department of Chemistry and Biochemistry Texas Tech University Lubbock Texas 79409-1061 USA3. State Key Lab of Coordination Chemistry Nanjing University Nanjing 210093 China

Aminohalogenation reaction of β-nitrostyrenes with N-halosuccinimides(N-chloro and N-bromosuccinimides) has been successfully conducted by using nickel acetate as a catalyst in the presence of potassium carbonate and succinimide as *** reaction was easily performed at room temperature under nitrogen gas protection to give dihalorinaed haloamino products in good to excellent yields(60%-98%).The structure has been confirmed by X-ray crystal structure analysis.

关键词： aminohalogenation vicinal haloamines β-nitrostyrenes NBS NCS

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A local spin evaluation into the active site models of [2.e2.] ferrodoxin [Fe_2._2.SR)_4.^(2.) (R=-H, -CH_3)

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Science china chemistry 2007年第3期50卷 327-334页

作者： WEI JiChong1,2. WANG Yan3 & JU GuanZhi2.3 1 department of chemistry, Hainan Normal University, Haikou 571158, {2. 2.State Key Laboratory of Theoretical and Computational chemistry, Jilin University, Changchun 13002., {2. 3 department of chemistry, Nanjing University, Nanjing 2.0093, {2. 1. department of chemistry Hainan Normal University Haikou 571158 China 2. State Key Laboratory of Theoretical and Computational chemistry Jilin University Changchun 130023 China 3. department of chemistry Nanjing University Nanjing 210093 China

To test the feasibility of local spin theory of Davidson and Clark for ferrodoxin clusters, the models [Fe2.2.SR)4.2. (R=-H, -CH3) are chosen for evaluation. This purpose is realized by calculating the local spin expectation values , 2.>, and mA and discussing the connection between these expected values and the Heisenberg spin model (HSM) and the Noodleman broken-symmetry approach. In practical calculation, the spin-unrestricted Hartree-Fock (UHF) and spin-polarized density functional theory (DFT) are used and the calculational qualities of these two methods are also discussed. In addition, the theoretical magnetic coupling constants JAB of these models are calculated by various computational schemes for comparison with both theoretical and experimental results previously reported.

关键词： local spin iron-sulfur protein model density function theory magnetic coupling constant

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Simultaneously inducing synthesis of semiconductor selenium multi-armed nanorods and nanobars through bio-membrane bi-templates

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Science china chemistry 2004年第6期47卷 507-511页

作者： LI Li1, WU Qingsheng1 DING Yaping2.& LI Ping3 1. department of chemistry, Tongji University, Shanghai 2.0092. {2. 2. department of chemistry, Shanghai University, Shanghai 2.04.6, {2. 3. department of Food, Anhui Agricultural University, Hefei 2.0036, {2. 1. department of chemistry Tongji University 200092 Shanghai China 2. department of chemistry Shanghai University 200436 Shanghai China 3. department of Food Anhui Agricultural University 230036 Hefei China

Multi-armed nanorods and nanobars of semiconductor selenium were simultane- ously synthesized in the light of biomineralization process through bio-membrane bi-templates of rush at room temperature. The multi-armed nanorods are 60 nm in diameter and 1.5 μm in length; the nanobars are 150 nm in diameter and 1000—1100 nm in length. The XRD pattern indicates that these nanocrystals were crystallized in the hexagonal structure with lattice constants a = 0.4.7 nm, c = 0.4.5 nm. The possible formation mechanism was investigated.

关键词： selenium, multi-armed nanorods, nanobars, bio-membrane, bi-templates.

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