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Theoretical Studies on the Isomerization of Peroxynitrite to Nitrate Mediated by Peroxynitrous Acid

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Chinese Journal of Structural Chemistry 2008年第2期27卷 171-176页

作者： LIU yong-Dong zhong Ru-Gang College of Life Science ＆ Bioengineering Beijing University of Technology Beijing 100022 China

The conversion of peroxynitrite （ONOO-） to nitrate （NO3-） mediated by peroxynitrous acid （ONOOH） has been investigated at the CCSD/6-311G（d）//B3LYP/6-31 1＋G（d,p） level. Two kinds of pathways for the title reaction were found. The results show that the energy barrier of isomerization through pathway 1 is around 25 kcal/mol in the gas phase. This value is significantly lower than that of isomerization without any catalysts. Thus, it indicates that ONOOH definitely makes the conversion from ONOO- to NO3- feasible. Although pathway 2 does not decrease the energy barrier of this isomerization, peroxynitric acid （O2NOOH） was obtained; moreover, this is a new pathway for this formation. In view of the results that peroxynitrate anion can decompose into nitrite and dioxygen, we conclude that our results are consistent with the experimental observation that nitrate, nitrite, and dioxygen are the main final products of the decay of peroxynitrite around pH 7.

关键词： peroxynitrite peroxynitrous acid isomerization DFT

Survey of polycyclic aromatic hydrocarbons(PAHs)in arterial street air of Hangzhou

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Journal of Environmental Sciences 2001年第1期13卷 8-13页

作者： ZHU Li zhong LIU yong jian Department of Environmental Science Zhejiang UniversityHangzhou 310028China

The presence of particulate and vapor PAHs, SO2 and NOx and other interrelated conditions (temperature, traffic intensity and wind velocity) were investigated in the arterial street air of Hangzhou. The concentration of the nine PAHs in the air was mean to 11.7 μg/m3, and the content of benzo(a) pyrene was up to 0.108 μg/m3. The contents of PAHs in the sampling sites were in good relation to the traffic intensity, and would be also affected by the terrain and meteorological conditions. The occurrences of PAHs in ambient air were mainly affected by their physical, chemical characters and temperature. The three- and four-ring PAHs (MW&le228) mainly existed in the vapor phase and the five-ring PAHs (MW > 228) existed predominately in the particulate phase. The fraction of vapor PAHs in the total nine PAHs was 84.2% in the air of the sampling sites. In the morning and evening, the concentrations of PAHs in the arterial street air were higher than that on the noon and the diurnal variation of PAHs was similar to that of the traffic gas NOx. A conclusion would be drawn that the major source of PAHs in the arterial street air was the traffic. And the results indicated that 75% of BaP would come from traffic source and remaining 25% of BaP would come from non-traffic source.

关键词： polycyclic aromatic hydrocarbons arterial street air pollution

MODIFIED BERNOULLI ITERATION METHODS FOR QUADRATIC MATRIX EQUATION

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Journal of Computational Mathematics 2007年第5期25卷 498-511页

作者： zhong-Zhi Bai yong-Hua Gao LSEC ICMSEC Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China

We construct a modified Bernoulli iteration method for solving the quadratic matrix equation AX^2 ＋ BX ＋ C = 0, where A, B and C are square matrices. This method is motivated from the Gauss-Seidel iteration for solving linear systems and the ShermanMorrison-Woodbury formula for updating matrices. Under suitable conditions, we prove the local linear convergence of the new method. An algorithm is presented to find the solution of the quadratic matrix equation and some numerical results are given to show the feasibility and the effectiveness of the algorithm. In addition, we also describe and analyze the block version of the modified Bernoulli iteration method.

关键词： Quadratic matrix equation Quadratic eigenvalue problem Solvent Bernoulli's iteration Newton's method Local convergence.

Coupled thermoelastic theory and associated variational principles based on decomposition of internal energy

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Acta Mechanica Sinica 2020年第1期36卷 107-115页

作者： jia-Hong Zheng Zheng zhong Cong-Ying jiang School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai200092China School of Science Harbin Institute of Technology(Shenzhen)Shenzhen518055GuangdongChina

A new framework of coupled thermoelasticity is constructed in this paper based on a decomposition of internal energy into free internal energy and dissipative *** equations(*** and gradient equations,constitutive equations including evolving laws)along with proper boundary conditions are all included in this framework,from which two novel dual-complementary variational principles with explicit functionals are *** the conventional thermoelastic theory,the proposed variational principles for thermoelasticity are established without the approximate assumption of small temperature *** verify the usefulness of the proposed variational principles in simulating coupled thermoelastic problems,a coupled thermoelastic example is numerically implemented.

关键词： Coupled thermoelasticity Thermodynamics Dissipation Variational principle

SIMULATION OF THE TWO PHASE FLOW OF DROPLET IMPINGEMENT ON LIQUID FILM BY THE LATTICE BOLTZMANN METHOD

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Journal of Hydrodynamics 2012年第2期24卷 292-297页

作者： GUO jia-hong WANG Xiao-yong Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics andMechanicsShanghai UniversityShanghai 200072China

A Lattice Boltzmann Method （LBM） with two-distribution functions is employed for simulating the two-phase flow induced by a liquid droplet impinging onto the film of the same liquid on solid *** model is suitable for solution of twophase flow problem at high density and viscosity ratios of liquid to vapor and phase transition between liquid and its *** roles of the vapor flow,the density ratio of liquid to vapor and the surface tension of the droplet in the splashing formation are *** is concluded that the vapour flow induced by the droplet fall and splash in the whole impinging process may affect remarkably the splash *** the case of large density ratio of liquid to vapor a crown may engender after the droplet collides with the ***,for the case of small density ratio of liquid to vapor a ＂bell＂ like splash may be observed.

关键词： droplet impact film two-phase flow Lattice Boltzmann Method (LBM) numerical simulation

Modified constriction particle swarm optimization algorithm

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Journal of Systems Engineering and Electronics 2015年第5期26卷 1107-1113页

作者： Zhe Zhang Limin jia yong Qin Traffic and Transportation School Beijing Jiaotong University State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing Research Center of Urban Traffic Information Sensing and Service Technologies Beijing Jiaotong University

To deal with the demerits of constriction particle swarm optimization(CPSO), such as relapsing into local optima, slow convergence velocity, a modified CPSO algorithm is proposed by improving the velocity update formula of CPSO. The random velocity operator from local optima to global optima is added into the velocity update formula of CPSO to accelerate the convergence speed of the particles to the global optima and reduce the likelihood of being trapped into local optima. Finally the convergence of the algorithm is verified by calculation examples.

关键词： particle swarm optimization random speed operator convergence global optima

17β-Estradiol Regulates SKP2 Expression in Cultured Immature Boar Sertoli Cells Mainly via Estrogen Receptor β,cAMP-PKA and ERK1/2

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Journal of Integrative Agriculture 2014年第4期13卷 827-836页

作者： WANG Xian-zhong ZHU Feng-wei WANG yong WANG Yi ZHANG jiao-jiao ZHANG jia-hua Chongqing Key Laboratory of Forage & Herbivore College of Animal Science and TechnologySouthwest University

Estrogen plays an important role in regulating testicular Sertoli cell number. Furthermore, S-phase kinase-associated protein 2 （SKP2） plays a central role in mammalian cell cycle progression. The objective of this study was to determine whether 17β-estradiol can regulate the expression of SKP2, and the Sertoli cell cycle, via estrogen receptor β （ERβ）, the cyclic adenosine monophosphate （cAMP）-protein kinase A （PKA） and extracellular signal-regulated kinase （ERK1/2） pathway. When cultured immature boar Sertoli cells were treated with 17β-estradiol, a time-dependent increase in SKP2 mRNA and protein level was observed by real-time PCR and Western blot, and 17β-estradiol activity peaked at 30 min. Treatment with ICI182780 and ERβ antagonist reduced 17β-estradiol-induced expression of SKP2 and proliferating cell nuclear antigen （PCNA）, while increasing the protein concentration of p27kip1. However, the effect of ERa antagonist on these parameters was lower than that of ICI 182780 and ERβ. Forskolin had a similar effect as 17β-estradiol on the expression of SKP2, PCNA and p27kip1, Rp-cAMP, H-89 and U0126 treatment reduced 17β-estradiol-induced changes, while H-89 also inhibited ERK1/2 activation. Therefore, 17β-estradiol mainly regulates SKP2 mRNA and protein expression via ERβ-cAMP-PKA and ERK1/2 activation. SKP2 and PCNA expression were positively correlated, while increased SKP2 expression likely resulted in p27kip1 degradation.

关键词： 17β-estradiol Sertoli cell SKP2 estrogen receptor cAMP-PKA ERK1/2

PHASE BEHAVIOR OF CHARGE STABLIZED COLLOID DISPERSION WITH ADDED WATER SOLUBLE POLYMERS

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Chinese Journal of Polymer Science 2013年第9期31卷 1218-1224页

作者： jia-xue Liu yong-feng Men State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

Demixing and colloidal crystallization in the mixture of charge stabilized colloidal poly（methyl methacrylate） particles and soluble poly（ethylene oxide） were investigated by means of synchrotron small-angle X-ray scattering （SAXS） technique. Phase diagram of the mixture was obtained based on visual inspection and SAXS results. The phase behavior is determined as a function of the concentration of the polymer as well as the volume fraction of the colloidal particles. The system shows a one phase region when the concentration of the polymer is low, whereas a two-phase region is present when the concentration of the polymer is larger than a critical concentration at certain volume fraction of the colloids. Interestingly, a face centered cubic colloidal crystalline structure was formed under certain conditions, which has been rarely observed in experiments of colloid-polymer mixtures with competing interactions.

关键词： Colloid-polymer mixture Phase behavior Crystallization.

Two New Sesquiterpenes from Ligularia Duciformis

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Chemical Research in Chinese Universities 1999年第1期15卷 72-74页

作者： GAO Kun jia zhong-jian Department of Chemistry National Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou 730000

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ＡｐｒｅｖｉｏｕｓｐｈｙｔｏｃｈｅｍｉｃａｌｓｔｕｄｙｏｆＬｉｇｕｌａｒｉａｄｕｃｉｆｏｒｍｉｓｄｅａｌｔｗｉｔｈｔｈｅｉｓｏｌａｔｉｏｎｏｆｃｏｎｉｆｅｒｙｌａｌｃｏｈｏｌｄｅｒｉｖａｔｉｖｅｓ［１，２］．Ｉｎｏｒｄｅｒｔｏｆｉｎｄｓｅｓｑｕｉｔｅ...

关键词： Ligularia duciformis Roots Sesquiterpenes Liguducin A Liguducin B 2D NMR