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Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2.molecule

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Science China(Physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1,2. SUN Weiguo1, HOU Shilin3 & FENG Hao4 1. Institute of Physics, college of Chemical Engineering, Sichuan {2., Chengdu 610065, China 2. Institute of Theoretical Physics, Xihua normal {2., Nanchong 637002. China 3. Department of Physics, China Oceanography {2., Qingdao 2.6003, China 4. college of Physics, Sichuan {2., Chengdu 610065, China Institute of Physics College of Chemical Engineering Sichuan University Chengdu China Institute of Theoretical Physics Xihua Normal University Nanchong China Department of Physics China Oceanography University Qingdao China college of Physics Sichuan University Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2.molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

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Deposition features of Ni on self-assembled microtubule template from biolipid by electroless method

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Science China chemistry 2004年第3期47卷 228-234页

作者： FU Yubin1,2. ZHANG Lide1, ZHENG Jiyong2. FU Shangang3 & ZHU Mingwei3 1. Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 2.0031, China 2. Luoyang Ship Material Research Institute, Luoyang 471039, China 3. college of Life Science, Henan {2. university, Xinxiang 453002. China Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China

Diacetylenic glycero-phosphatidylcholine is a chiral molecule with amphiphilic property, and it can self-assembly into a lipid microtubular structure. The lipid microtubule is a stable structure formed by tightly wound helical ribbons, and the ribbon-wrapping patterns have a significant effect on their chemical deposition on the microtubules. The deposition of colloidal Pd catalyst occurs mainly on the helical edge of the wound helical ribbons to form helical deposition lines of colloidal Pd particles in the interior and exterior of the lipid microtubules, resulting in an uneven chemical deposition of Ni on the microtubules. Catalyzed by as-deposited colloidal Pd, metallized Ni microtubules are characterized by a helical form, which may be in relation to inner stress due to the thickness difference or the different deposition processes. The observation of microtom shows that metallized tubules have a hollow structure. Some metallized tubules have a kind of coaxial double layer structure observed in the direct experiment evidence, indicating that metallization can occur in the inner and outer surface of the lipid tubules. Both lipid microtubules and metallized microtubules can be used as vehicles for encapsulating biological active molecules to control their release and to develop micro-components in biological and mechanical systems. Keywords molecular self-assembly - lipid microtubules - helical pattern - site-specific deposition - electroless metallization

关键词： molecular self-assembly, lipid microtubules, helical pattern, site-specific deposition, electroless metallization.

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The toxicity of Cu^(2.) to Microcystis aeruginosa using dielectric spectroscopy

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Science China chemistry 2010年第3期53卷 631-636页

作者： YU YanLi1,BAI Wei1,ZHAO KongShuang1& ZHOU YunLong2.1college of chemistry,Beij{2. normal university,Beij{2. 100875,China 2.0} of Life Science,Beij{2. normal university,Beij{2. 100875,China college of chemistry Beijing Normal University Beijing China college of Life Science Beijing Normal University Beijing China

Dielectric spectroscopy(DS) was utilized to investigate the toxicity of the Cu2. solution to Microcystis *** was found that 0.04 mM Cu2. had no effect on dielectric increment,whereas the Cu2. concentrations above 0.1 mM decreased the value of Δε/Δε *** toxic effect of Cu2. on *** cells was time-dependent and *** was a threshold concentration between 0.04 mM and 0.1 mM,which affected the cell membrane,suggesting that Cu2. at the concentrations higher than 0.1 mM caused serious plasmalemma damage to *** *** addition of 1 mM Ca2. or Mg2. did not protect *** cells from 1 mM Cu2. *** study demonstrates that DS monitors cell biomass facilitating observation of the toxic effects of metal ions.

关键词： Microcystis aeruginosa dielectric spectroscopy dielectric increment cupric ion toxicity

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Kinetics and mechanism of the reaction between thiourea and iodate in unbuffered medium

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Science China chemistry 2004年第6期47卷 480-487页

作者： WANG Shun1,2. LIN Juanjuan1, CHEN Fan1, HU Maolin1, HU Xingen1, HAN Yiping1 & GAO Qingyu2.1.Department of chemistry and Material Science, Wenzhou normal college, Wenzhou 32.02., China 2. college of Chemical Engineering, China university of Mining and Technology, Xuzhou 2.1008, China Department of chemistry and Material Science Wenzhou Normal College Wenzhou 325027 China

The reaction between iodate and thiourea has been studied in an unbuffered acidic medium. In excess iodate the reaction shows not only oligooscillations in pH, Pt potential and the concentration of iodide ion, [I?], but also an initial induction period which has the linear relation with initial pH. At the end of the induction period, [I?] decreases sharply and a yellow coloration (due to iodine) appears transiently. While in excess thiourea iodine is produced and finally con- sumed, leaving milky deposits (due to sulfur) at the end of the reaction. The induction period from the start of the reaction to the maximum of [I2. is also directly proportional to initial pH. A 14-step mechanism, including a H+-mediated preequalibrium, Dusman reaction, iodine-sulfur reactions and sulfur-sulfur reactions, is proposed. Computer simulations using this mechanism give good agreement with experiments.

关键词： oligooscillations, pH dynamics, thiourea, iodate, complex reaction mechanism, dynamic simulation.

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Synthesis and Conductivity of Undecatungstocobaltoruthenic Polyoxometallic Acid

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Chemical Research in Chinese Universities 2012年第1期28卷 1-3页

作者： XU Sheng-xian1,2. WU Qing-yin2.and YAN Wen-fu3 1. School of chemistry and Chemical Engineering, Jiangxi Science & Technology normal university, Nanchang 330013, P. R. China 2. Department of chemistry, Zhejiang university, Hangzhou 31002., P. R. China 3. State Key Laboratory of Inorganic Synthesis and Preparative chemistry, Jilin university, Changchun 130012. P. R. China School of chemistry and Chemical Engineering Jiangxi Science & Technology Normal University Nanchang 330013 Department of chemistry Zhejiang University Hangzhou 310027 Jilin university State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Changchun 130012

Undecatungstocobaltoruthenic polyoxometallic acid H7[Ru（H2.）CoW11O39] 2.H2. was synthesized by the stepwise acidification and the stepwise addition of solutions of the component elements as well as the ion ex changing-cooling method. The optimal proportion of the component compound and the pH of the synthesis reaction were given. The product was characterized by means of inductively coupled plasma（ICP）, IR, UV and thermal analy sis. The IR and UV results indicate that H7[Ru（H2.）CoW11O39] 2.H2. possesses the Keggin structure. The results of AC impedance measurement show that its proton conductivity is 2.30×10-3 S/cm at room temperature（2.5 K） and a relative humidity of 75%.

关键词： Polyoxometallic acid Keggin structure Conductivity Ruthenium

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Theoretical study of the mechanism for C-H bond activation in spin-forbidden reaction between Ti^+ and C_2._4

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Science China chemistry 2009年第3期52卷 295-303页

作者： LV LingLing1, LIU XinWen1, YUAN Kun1, WANG XiaoFang1 & WANG YongCheng2.1 {2. of Life Science and chemistry, Tianshui normal university, Tianshui 741001, China 2.{2. of chemistry and Chemical Engineering, Northwest normal university, Lanzhou 730070, China college of Life Science and chemistry Tianshui Normal University Tianshui China college of chemistry and Chemical Engineer{2. Northwest Normal University Lanzhou China

The mechanism of the spin-forbidden reaction Ti+(4F, 3d2.s1) + C2.4 → TiC2.2. (2.2. + H2.on both doublet and quartet potential energy surfaces has been investigated at the B3LYP level of theory. Crossing points between the potential energy surfaces and the possible spin inversion process are discussed by means of spin-orbit coupling (SOC) calculations. The strength of the SOC between the low-lying quartet state and the doublet state is 59.3 cm-1 in the intermediate complex IM1-4B2. Thus, the changes of its spin multiplicity may occur from the quartet to the doublet surface to form IM1- 2.1, leading to a sig-nificant decrease in the barrier height on the quartet PES. After the insertion intermediate IM2. two dis-tinct reaction paths on the doublet PES have been found, i.e., a stepwise path and a concerted path. The latter is found to be the lowest energy path on the doublet PES to exothermic TiC2.2. (2.2. + H2.products, with the active barrier of 4.52.kcal/mol. In other words, this reaction proceeds in the following way: Ti++C2.4 →4IC→IM1-4B2.4,2.SC→IM1- 2.1→[2.Sins]→IM2.[2.SMCTS]→IM5→TiC2.2.(2.2.+H2.

关键词： Ti+(4F) and C2.4 spin-forbidden reaction mechanism spin-orbit coupling (SOC) concerted path

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Synthesis and 183W NMR Characterization of α-K7GaW11（TiO2.O39·11H2. Heteropolyanion

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Chinese Chemical Letters 2001年第8期12卷 731-732页

作者： Xiao Peng ZHAN2. Lu MENG1* 1Faculty of chemistry, Northeast normal {2., Changchun 13002. 2.epartment of chemistry, Yangzhou college of Education, Yangzhou 2.5002 Department of chemistry Yangzhou College of Education Yangzhou 225002 China Faculty of chemistry Northeast Normal University Changchun 130024 China

The peroxotitanium-substituted heteropolytungstate (-K7GaW11(TiO2.O39(11H2. has been synthesized and characterized by elemental analysis, IR, UV, 183W NMR and electrochemistry. 183W NMR spectrum consists of six lines with intensity ratio 2.2.1:2.2.2. indicated that the TiO2.occupied the empty octahedral site of the GaW11 anion forming a polyanion with Cs symmetry. The characteristic charge-transfer absorption band O2.-?Ti at 385 nm occurs in the UV spectrum. The polarographic reduction potential of O2.- at ca.+0.87 V has been found.

关键词： Peroxotitanium gallatotungstate Keggin structure 183W NMR.

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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, 95,100 and 180 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

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Adjoint method for the optimum planning of industrial pollutant sources

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Science China Earth Sciences 2005年第8期48卷 1270-1279页

作者： LIU Feng1,2. HU Fei2.& ZHU Jiang2.1. college of Environmental Sciences, Peking {2., Beijing 100871, China 2. LAPC, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002., China college of Environmental Sciences Peking University Beijing China LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.

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Speciation of the elements and compositions on the surfaces of dust storm particles:The evidence for the coupling of iron with sulfur in aerosol during the long-range transport

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Chinese Science Bulletin 2005年第8期50卷 738-744页

作者： ZHANG Xingying1,2. ZHUANG Guoshun1,2.3, CHEN Jianmin2.& XUE Huaxin2.1. Center for Atmospheric Environment Study, Department of {2., Beijing normal university, Beijing 100875, China 2. Center for Atmospheric {2. Study, Department of Environ- mental Science and Engineering, Fudan university, Shanghai 2.0433, China 3. LAPC/NZC, Institute of Atmospheric Physics, NZC/LAPC, Chinese Academy of Sciences, Beijing 10002., China Center for Atmospheric Environment Study Department of Chemistry Beijing Normal University Beijing 100875 China Center for Atmospheric chemistry Study Department of Environmental Science and Engineering Fudan University Shanghai 200433 China LAPC/NZC Institute of Atmospheric Physics NZC/LAPC Chinese Academy of Sciences Beijing 100029 China

The speciation of the elements on the surface of the particles collected during dust storm and non-dust storm in Beijing and Inner Mongolia was studied by XPS. The ma- jor species of iron on the surface were oxides, sulfate, silicate, FeOOH and minor part sorbed on SiO2.Al2.3. Sulfate is the dominant species of sulfur on the surface. SiO2.and Al2.3 are the main components of Si and Al on the surface respectively. One of the most important findings was that the Fe(II) (FeS and FeSO4) produced could account for up to 44.3% and 45.6% of the total Fe on the surface in the aerosol sample collected at that night and next day of the “peak” time of the dust storm occurring on March 2., 2.02. while Fe2.SO4)3, one of the Fe(III) species on the surface decreased from 67.1% to 49.5% and 48.0% respectively. Both S and Fe en- riched on the surface of aerosol particles. Fe(II) accounted for 1.3%?5.3% of total Fe in bulk aerosol samples during dust storm. These results provided strong evidence to sup- port the hypothesis of the coupling between iron and sulfur in aerosols during the long-range transport, which would have important impact on the global biogeochemical cycle.

关键词：物种形成原理 XPS 大气悬浮物 Fe-S结合粒子集合

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