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Theoretical Studies of Water’s and Methanol’s Effects on Alcoholysis of N-Benzyl-3-oxo-β-sultam

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Chinese Journal of Structural Chemistry 2007年第9期26卷 1118-1124页

作者：孙孝敏何茂霞冯大诚蔡政亭 Environment Research Institute Shandong University Institute of Theoretical Chemistry Shandong University

The mechanisms about the water’s and methanol’s effects on the alcoholysis of N-benzyl-3-oxo-β-sultam together with their differences have been studied by using density func- tional theory at the B3LYP/6-31G＊ level. The results, in comparison with a previous study on the relative reaction without the assistance of water and methanol, show that the added water or methanol can remarkably reduce the energy barrier of alcoholysis reaction of N-benzyl-3-oxo- β-sultam and the most favorite pathway is the breaking of C–N bond instead of S–N. It is also found that the reaction energy barrier of methanol-assisted alcoholysis is a little higher than that of the water-assisted one.

关键词： alcoholysis N-benzyl-3-oxo-β-sultam water-assisted methanol-assisted

Inhibitory Effect of Extracellular Polysaccharide EPS-II from Pseudoalteromonas on Candida adhesion to Cornea in vitro

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Biomedical and Environmental Sciences 2012年第2期25卷 210-215页

作者： CHEN Hao ZHENG Zhou CHEN Peng WU Xiang Gen ZHAO Ge State Key Lab Cultivation Base Shandong Provincial Key Lab of OphthalmologyShandong Eye InstituteQingdao 266071ShandongChina Key Laboratory of Marine Bio-active Substances First Institute of OceanographyState Oceanic AdministrationQingdao 266061ShandongChina.

Objective Fungal keratitis（FK） is a vision-threatening infection,whose treatment requires more effective and safer anti-fungal agent exploitation *** this aim,we focused on the effect of an extracellular polysaccharide on fungal adhesion to human corneal epithelial *** We performed the cytotoxicity assays of the extracellular polysaccharide EPS-II from an antarctic bacterium Pseudoaltermonas and evaluated its inhibitory effect on Candida albicans cells＇ adherence to human corneal epithelial cells（HCECs）.Results EPS-II,which displayed minor cytotoxicity but also promoted proliferation of HCECs,could inhibit the adherence of yeast cells to HCECs in a dose-dependent ***-II could also suppress the subsequent PI3K/AKT signaling pathway,and thereby decrease the expression of early inflammatory *** ExtracellularpolysaccharideEPS-IIwassuggestedasanewnaturalagentforattenuatingFK.

关键词： Extracellular polysaccharide EPS-II Candida albicans Cornea Adhesion Inhibitory effect

Characterization of arsenate transformation and identification of arsenate reductase in a green alga Chlamydomonas reinhardtii

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Journal of Environmental Sciences 2011年第7期23卷 1186-1193页

作者： Xixiang Yin Lihong Wang Guilan Duan Guoxin Sun Key Laboratory of Urban Environment and Health Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China shandong Analysis and Test Center Shandong Academy of Sciences Shandong 250014 China

Arsenic （As） is a pervasive and ubiquitous environmental toxin that has created catastrophic human health problems world-wide. Chlamydomonas reinhardtii is a unicellular green alga, which exists ubiquitously in freshwater aquatic systems. Arsenic metabolism processes of this alga through arsenate reduction and sequent store and efflux were investigated. When supplied with 10 μmol/L arsenate, arsenic speciation analysis showed that arsenite concentration increased from 5.7 to 15.7 mg/kg dry weight during a 7-day period, accounting for 18%–24% of the total As in alga. When treated with different levels of arsenate （10, 20, 30, 40, 50 μmol/L） for 7 days, the arsenite concentration increased with increasing external arsenate concentrations, the proportion of arsenite was up to 23%–28% of the total As in alga. In efflux experiments, both arsenate and arsenite could be found in the efflux solutions. Additionally, the efflux of arsenate was more than that of arsenite. Furthermore, two arsenate reductase genes of C. reinhardtii （CrACR2s） were cloned and expressed in Escherichia coli strain WC3110 （？arsC） for the first time. The abilities of both CrACR2s genes to complement the arsenate- sensitive strain were examined. CrACR2.1 restored arsenate resistance at 0.8 mmol/L. However, CrACR2.2 showed much less ability to complement. The gene products were demonstrated to reduce arsenate to arsenite in vivo. In agreement with the complementation results, CrACR2.1 showed higher reduction ability than CrACR2.2, when treated with 0.4 mmol/L arsenate for 16 hr incubation.

关键词： arsenate accumulation reduction efflux arsenate reductase Chlamydomonas reinhardtii

Identity-based strong designate verifier signature over lattices

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The Journal of China Universities of Posts and Telecommunications 2014年第6期21卷 52-60页

作者： WANG Feng-he HU Yu-pu WANG Chun-xiao Department of the Mathematics and Physics Shandong Jianzhu University State Key Laboratory of Integrate Services Networks Xidian University

The notion of the identity-based（id-based） strong designate verifier signature（SDVS） was extent to the lattice-based cryptography. The authors proposed an id-based SDVS scheme over lattices by using the basis delegation technical in fixed dimension. The proposed scheme is based on the hardness of the learning with errors（LWE） problem, and the unforgeability against adaptive chosen message and selective identity attack is based on the hardness of the short integer solution（SIS） problem in the random oracle model. If the parameters m, n and q are the same, the signature length of this scheme is only 3mlbq bits shorter than（3m＋n） lb q bits which is the signature length of the known lattice-based SDVS scheme in the public key environment. As a result, the proposed scheme is not only id-based but also efficient about the signature length and the computation cost. Moreover, this article also proposed an id-based strong designate verifier ring signature（SDVRS） scheme based on the proposed SDVS scheme, which satisfies anonimity, unforgeability.

关键词： SDVS lattice-based cryptography id-based cryptography Gaussian sample SIS problem LWE problem

Phase Structures of （K0.48Na0.52）0.945Li0.055Sb0.05Nb0.95O3 Piezoceramics

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Chinese Physics Letters 2010年第1期27卷 242-244页

作者：臧国忠仪修杰徐志军付鹏赵利民蒲锡鹏 School of Materials Science and Engineering Liaocheng University Liaocheng 252059

The phase structures of lead-free （K0.48Na0.52）0.945Li0.055Sb0.05Nb0.95O3 piezoceramics are studied based on the measurements of ferroelectric and dielectric properties as well as the analyses of x-ray diffraction pattern and energy dispersive spectroscopy. The poled samples exhibit orthorhombic structure whereas the surface and interior for unpoled samples exhibit tetragonal and tetragonal-orthorhombic coexistent structures, respectively. These results are in agreement with the relative permittivity-temperature curves and demonstrate that phase transitions can be induced by Na volatilization and poling process. The remnant polarization Pr measured at 20°C increases continuously with the increase of electric field in the range of 2000-4000V/mm. This indicates that the polymorphic structure is more beneficial to the rotation or reorientation of dipoles than either the orthorhombic or the tetragonal structure. The randomly oriented domains may be the essential reason for the continuous rotation or reorientation and not good thermal stability.

关键词： Measurement Sodium Sampling Exhibitions Poles Dispersants

Infinite Interval Backward Stochastic Differential Equations in the Plane

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Acta Mathematicae Applicatae Sinica 2003年第3期19卷 485-490页

作者： Yan-ling GuSchool of Mathematics and System Sciences, shandong University, Jinan 250100, China School of Mathematics and System Sciences Shandong University Jinan China

This paper studies the existence and uniqueness of solution of infinite interval backward stochastic differential equation (BSDE) in the plane driven by a Brownian sheet.

关键词： Two-parameter mixed type BSDE

Density Functional Theory Study on the Histidine-assisted Mechanism of Arylamine N-Acetyltransferase Acetylation

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Chinese Journal of Structural Chemistry 2008年第9期27卷 1127-1133页

作者：乔青安高善民靳月庆陈鑫孙孝敏杨传路 School of Chemistry and Materials Science Ludong University Library of Ludong University College of Life Science Shandong University School of Physics and Electronic Engineering Ludong University

Arylamine N-acetyltransferases （NATs, EC 2.***.1.5） catalyze the N-acetylation of primary arylamines, and play a key role in the biotransformation and metabolism of drugs, carcinogens, etc. In this paper, three possible reaction mechanisms are investigated and the results indicate that if the acetyl group directly transfers from the donor to the acceptor, the high activation energies will make it hard to obtain the target products. When using histidine to mediate the acetylation process, these energies will drop in the 15-45 kJ/mol range. If the histidine residue is protonated, the corresponding energies will be decreased by about 35-87 kJ/mol. The calculations predict an enzymatic acetylation mechanism that undergoes a thiolate-imidazolium pair, which agrees with the experimental results very well.

关键词： arylamine N-acetyltransferase density functional theory acetyl group transfer histidine-assisted mechanism

Hamming-distance-based adaptive quantum-inspired evolutionary algorithm for network coding resources optimization

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The Journal of China Universities of Posts and Telecommunications 2015年第3期22卷 92-99页

作者： Qu Zhijian Liu Xiaohong Zhang Xianwei Xie Yinbao Li Caihong School of Computer Science and Technology Shandong University of Technology

An adaptive quantum-inspired evolutionary algorithm based on Hamming distance （HD-QEA） was presented to optimize the network coding resources in multicast networks. In the HD-QEA, the diversity among individuals was taken into consideration, and a suitable rotation angle step （RAS） was assigned to each individual according to the Hamming distance. Performance comparisons were conducted among the HD-QEA, a basic quantum-inspired evolutionary algorithm （QEA） and an individual＇s fitness based adaptive QEA. A solid demonstration was provided that the proposed HD-QEA is better than the other two algorithms in terms of the convergence speed and the global optimization capability when they are employed to optimize the network coding resources in multicast networks.

关键词： network coding quantum-inspired evolutionary algorithm Hamming distance multicast network

Studies of Rigid Rotor-Rigid Surface Scattering in Dynamical Lie Algebraic Method

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Communications in Theoretical Physics 2004年第3期41卷 357-361页

作者： WANGXiao-Yan DINGShi-Liang SchoolofPhysicalandMicroelectronics ShandongUniversityJinan250100China

The dynamical Lie algebraic method is used for the description of statistical mechanics of rotationally inelastic molecule-surface scattering. It can give the time-evolution operators about the low power of and by solving a set of coupled nonlinear differential equations. For considering the contribution of the high power of and , we use the Magnus formula. Thus, with the time-evolution operators we can get the statistical average values of the measurable quantities in terms of the density operator formalism in statistical mechanics. The method is applied to the scattering of (rigid rotor) by a flat, rigid surface to illustrate its general procedure. The results demonstrate that the method is useful for describing the statistical dynamics of gas-surface scattering.

关键词： Lie algebraic method scattering rigid rotor