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Acta Mathematica Scientia 2020年第5期40卷 1195-1214页

作者： lishuang PENG College of Science University of Shanghai for Science and TechnologyShanghai 200093China

We consider the large time behavior of solutions of the Cauchy problem for the one-dimensional compressible Navier-Stokes equations for a reacting *** the corresponding Riemann problem for the Euler system admits a contact discontinuity wave,it is shown that the viscous contact wave which corresponds to the contact discontinuity is asymptotically stable,provided the strength of contact discontinuity and the initial perturbation are suitably *** apply the approach introduced in Huang,Li and Matsumura(2010)[1]and the elemen tary L2-energy met hods.

关键词： reacting mixture viscous contact wave asymptotic stability energy estimates

Rural-urban Migration, Rural Household Income and Local Geographical Contexts——A Case of Northwestern Guangxi, China

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Chinese Geographical Science 2008年第1期18卷 17-23页

作者： YANG Chunyue LU Qi XIE lishuang Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China Central University for Nationalities Beijing 100081 China

This paper aims to examine New Economics of Labor Migration (NELM) in the northwestern Guangxi, China and investigate the relationships among rural-urban migration, rural household income and local geographical contexts. Stratified sampling and typical case study were adopted and 236 questionnaires were collected from four vil- lages, Daxin, Lixin, Longhe and Yongchang. We analyzed the rural-urban migration rate, household income and local geographical factors, focusing on the ratio of remittance income to total household income. Data descriptions and sta- tistical methods, such as Pearson Chi-square test, Contingency coefficient, Eta, Pearson correlation coefficient, t-test, multiple comparisons (LSD test, Tamhane T2, Dunnett T3 and Dunnet C test) were used. The results are as follows. Rural households’ income is diversified in survey villages so the motivation of rural-urban migration in the study area can be partly explained by NELM. The migration rate of households (the percentage of households with migrants in survey households) in survey villages varies from 50% to 86%, while the proportion of remittance income to house- hold income is in the range of 30% to 80%. In the village of Yongchang, with the least average arable land area per household, the remittance income plays a vital role in household income (80%). And the statistical findings show that the proportion is significantly and negatively correlated with arable land area per household. The conclusion is that di- rect effect of migration, i.e., the contribution of remittance to household income, is negatively correlated with the con- tribution of resources to local income.

关键词： rural-urban migration household income local geographical contexts northwestern Guangxi

Oxidative degradation of phenol by sulfidated zero valent iron under aerobic conditions:The effect of oxalate and tripolyphosphate ligands

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Journal of Environmental Sciences 2021年第2期33卷 82-89页

作者： Xianglong Kong Chengwu Zhang Jingyi Zhang lishuang Xuan Chuanyu Qin Key Laboratory of Groundw ater Resources and Environment Ministry of EducationJilin UniversityChangchun 130021China Jilin Prouindal Key Laboratory of Water Resources and Enuironment jinin UniversityChangchun 130021China National and Local Joint Engineering Laboratory for Petrochem ical Contaminated Site Control and Remediation Technology Jilin UniversityChangchun 130021China

After adding either organic or inorganic ligands,sulfidated nano-zero-valent iron(Sn ZVI)was used for aerobic degradation of phenol,and the effect of the ligand species on oxidation performance was *** found that Sn ZVI hardly degraded phenol in the absence of ligand *** initiated and promoted the degradation of pollutants by Sn *** data herein show that a characteristic inorganic ligand,tripolyphosphate(TPP),is more effective in enhancing oxidation than a characteristic organic ligand *** addition to the scavenging of reactive oxidants by the organic ligand,more ferrous ion(Fe(Ⅱ))dissolution from Sn ZVI in the TPP system is another cause for the superior enhancement by the inorganic *** the oxalate system,as the sulfur content of Sn ZVI increased,the oxidation efficiency increased because Fe S shell promoted the transfer of electrons to produce more reactive oxygen species(ROS).In TPP system,the effect of sulfur content on oxidation performance is more *** Sn ZVI with low sulfur content showed poor oxidation performance compared with that of n *** experiments proved that sulfidation might weaken the complexation of TPP with surface bound Fe,which would slow down the ionic Fe(II)dissolution ***,sulfidation has the dual effects of enhancing electron transfer and inhibiting the complexation of inorganic *** addition,the mechanisms of ROS generation in different ligand systems were investigated *** showed that the critical ROS in both the oxalate and TPP systems are hydroxyl radicals,and that they are produced via one-electron activation of O_(2).

关键词： Zero valent iron Sulfidation Tripolyphosphate Oxalate Oxygen activation

Directed Evolution of L-Aspartase by Mobility of Domains

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Chemical Research in Chinese Universities 2004年第1期20卷 50-54页

作者： GOUXiao-jun lishuang KONGXiang-duo LIUWei SUNYan-hong ZHANGJin TheJointLaboratoryofMolecularEvolutionandEngineering DepartmentofBioengineeringChengduUniversityChengdu610106P.R.China KeyLaboratoryforMolecularEnzymologyandEngineeringofMinistryofEducation JilinUniversityChangchun130023P.R.China

To enhance the relative movement of domains, we inserted a random sequence of fifteen-peptide into the three domains of L-aspartase. By means of directed screening, the three isoforms of monomeric, dimmeric and tetrameric enzymes were obtained. Compared to the wild-type tetrameric L-asparease, these mutants remained 19.7%, 42.3%, and 92% of the enzyme activity, respectively. Moreover, the examination of enzyme properties revealed that their k_ cat and K_M changed in varying degrees, and the optimum pH shifted towards acidic pH, while the dependence of the activity of enzyme on Mg 2+ concentration and thermostability increased. Therefore this strategy provides a novel approach to directed evolution of enzymes.

关键词： Directed evolution Domain L-aspartase Mobility

Natural disaster warning system for safe operation of a high-speed railway

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Transportation Safety and Environment 2021年第4期3卷 34-45页

作者： Hu Qizhou Fang Xin Bian lishuang School of Automation Nanjing University of Science and TechnologyNanjing 210094China

In this paper,the least square support vector machine(LSSVM)is used to study the safety of a high-speed *** to the principle of LSSVM regression prediction,the parameters of the LSSVM are optimized to model the natural disaster early warning of safe operation of a high-speed railway,and the management measures and methods of high-speed railway safety operation under natural disasters are *** relevant statistical data of China’s high-speed railway are used for training and *** experimental results show that the LSSVM can well reflect the nonlinear relationship between the accident rate and the influencing factors,with high simulation accuracy and strong generalization ability,and can effectively predict the natural disasters in the safe operation of a high-speed ***,the early warning system can improve the ability of safety operation evaluation and early warning of high-speed railway under natural disasters,realize the development goals of high-speed railway(safety,speed,economic,low-carbon and environmental protection)and provide a theoretical basis and technical support for improving the safety of a high-speed railway.

关键词： high-speed railway safe operation natural disaster early warning system least square support vector machine(LSSVM)

Geographical Variation and Influencing Factors of Spartina alterniflora Expansion Rate in Coastal China

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Chinese Geographical Science 2020年第1期30卷 127-141页

作者： ZHANG Danhua HU Yuanman LIU Miao CHANG Yu SUN lishuang School of Transportation Engineering Shenyang Jianzhu UniversityShenyang 110168China Institute of Applied Ecology Chinese Academy of SciencesShenyang 110164China

Biological invasion poses a huge threat to ecological *** alterniflora was introduced into China in 1979,and its arrival corresponded with negative effects on native *** explore geographical variation of its expansion rate in coastal China,we selected 43 *** sites from Tianjin Coastal New Area to *** area expansion rate,expansion rate paralleling and vertical to the shoreline were analysed based on Landsat images and field survey in *** Ocean Data Assimilation(SODA)and climate data were collected to statistically analyse the influential factors of expansion *** showed that significant difference of *** area expansion rate among different latitude zones(P<0.01),increasing from 6.08%at southern(21°N–23°N)to 19.87% in Bohai Bay(37°N–39°N)along latitude *** was a significant difference in expansion rate vertical to shoreline in different latitude zones(P<0.01)with the largest occurring in Bohai Bay(256m/yr,37°N–39°N),and showed an decreasing tendency gradually from north to *** significant difference and latitudinal clines in expansion rate paralleling to shoreline were *** rate had significant negative correlation with mean seawater temperature,the lowest seawater temperature,current zonal velocity and meridional velocity and presented a reducing trend as these biotic factors increased;however,they were not significantly correlated with the highest seawater temperature and mean seawater *** identified significant correlations between expansion rate and annual mean temperature,the lowest temperature in January and annual precipitation,but there was little correlation with annual diurnal difference in temperature and the highest temperature in *** rapid expansion rate in high-latitude China demonstrated a higher risk of potential invasion in the north;dynamic monitoring and control management should be established as soon as possible.

关键词： geographical variation biological invasion Spartina alterniflora expansion rate coastal wetlands China

Construction of Hybrid Enzyme from HEC-SOD and Cu,Zn-SOD

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Chemical Research in Chinese Universities 2004年第1期20卷 55-59页

作者： GOUXiao-jun ZHANGZhong-hua lishuang KONGXiang-duo SUNYan-hong LIUWei ZHAGNJin TheJointLaboratoryofMolecularEvolutionandEngineering DepartmentofBioengineeringChengduUniversityChengdu610106P.R.China KeyLabforMolecularEnzymologyandEngineeringofMinistryofEducation JilinUniversityChangchun130023P.R.China

Human extracellular superoxide dismutase(hEC-SOD) is a secreted tetrameric protein involved in the protection of a human body from oxygen free radicals. Its three-dimensional structure has not been confirmed. hEC-SOD couldn′t be expressed in ***. We constructed a hybrid enzyme, which comprises the N-terminal and C-terminal domains from hEC-SOD, fused it to human Cu,Zn-SOD. The hybrid enzyme is expressed successfully in ***. Further, we analyzed the expression of hEC-SOD in *** by mRNA differential displaying.

关键词： Extracellular superoxide dismutase Hybrid enzyme mRNA differential displaying

Biodegradation of Phthalate Esters by a Newly Isolated Acinetobacter sp. Strain LMB-5 and Characteristics of Its Esterase

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Pedosphere 2017年第3期27卷 606-615页

作者： FANG Yue ZHANG lishuang WANG Jing ZHOU Ying YE Bangce Lab of Biosystems and Microanalysis State Key Laboratory of Bioreactor Engineering East China University of Science and Technology School of Chemistry and Chemical Engineering Shihezi University

Phthalate esters （PAEs） are extensively applied in industry, and they migrate to environment during the process of production, employ, and treatment and axe difficult to be degraded in nature. However, some microorganisms could use them as the carbon source to growth. In this study, an Acinetobacter sp. strain LMB-5, capable of utilizing PAEs, was isolated from a vegetable greenhouse soil. The degradation capability of strain LMB-5 was also investigated by incubation in mineral salt medium containing different PAEs, dimethyl phthalate （DMP）, diethyl phthalate （DEP）, di-n-butyl phthalate （DBP）, and di-（2-ethylhexyl） phthalate （DEHP）. The strain could grow well with DMP, DEP, DBP, and DEHP. When the concentration of DBP increased from 100 to 400 mg L-1, the half-life extended from 9.5 to 15.5 h. In the concentration range of DBP, the degradation ability of strain LMB-5 could be described by first-order kinetics. During the biodegradation of DBP, three intermediates, 1,2-benzenedicaxboxylic acid,butyl methyl ester, DMP, and phthalic acid （PA） were detected, and the proposed pathway of DBP was identified. By analysis of bioinformatics, one esterase was cloned from the genome of LMB-5 and expressed in Escherichia coll. It displayed an ability to break the ester bonds of DBP. The enzyme exhibited maximal activity at pH 7.0 and 40 ℃ with DBP as the substrate. It was activated by Cu2＋ and Fe3＋ and had a high activity in the presence of low concentrations of methanol or dimethylsulfoxide （each 10%, volume：volume）. The Acinetobacter sp. strain LMB-5 may make a contribution to the remediation of soils polluted by PAEs in the future.

关键词： biological toxicity degradation bacteria di-n-butyl phthalate enzymatic activity hydrolase soil pollution

Stochastic DoS Attack Allocation Against Collaborative Estimation in Sensor Networks

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IEEE/CAA Journal of Automatica Sinica 2020年第5期7卷 1225-1234页

作者： Ya Zhang lishuang Du Frank L.Lewis School of Automation Southeast Universityand also with the Key Laboratory of Measurement and Control of Complex Systems of EngineeringMinistry of EducationNanjing 210096China University of Texas at Arlington Research Institute Fort WorthTX 76118 USA IEEE

In this paper,denial of service(DoS)attack management for destroying the collaborative estimation in sensor networks and minimizing attack energy from the attacker perspective is *** the communication channels between sensors and a remote estimator,the attacker chooses some channels to randomly jam DoS attacks to make their packets randomly dropped.A stochastic power allocation approach composed of three steps is ***,the minimum number of channels and the channel set to be attacked are ***,a necessary condition and a sufficient condition on the packet loss probabilities of the channels in the attack set are provided for general and special systems,***,by converting the original coupling nonlinear programming problem to a linear programming problem,a method of searching attack probabilities and power to minimize the attack energy is *** effectiveness of the proposed scheme is verified by simulation examples.

关键词： Attack allocation denial of service(DoS)attack packet loss remote estimation sensor networks

Degradation of organic contaminants through the activation of oxygen using zero valent copper coupled with sodium tripolyphosphate under neutral conditions

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Journal of Environmental Sciences 2020年第4期32卷 375-384页

作者： Chengwu Zhang lishuang Xuan Jingyi Zhang Fang Yuan Xianglong Kong Chuanyu Qin Key Laboratory of Groundwater Resources and Environment Ministry of EducationJilin UniversityChangchun 130021China Jilin Provincial Key Laboratory of Water Resources and Environment Jilin UniversityChangchun 130021China National and Local Joint Engineering Laboratory for Petrochemical Contaminated Site Control and Remediation Technology Jilin UniversityChangchun 130021China

In this study,sodium tripolyphosphate(STPP)was used to promote the removal of organic pollutants in a zero-valent copper(ZVC)/O2 system under neutral conditions for the first time.20 mg/L p-nitrophenol(PNP)can be completely decomposed within 120 min in the ZVC/O2/STPP *** PNP degradation process followed pseudo-first-order kinetics and the degradation rate of PNP gradually increased upon the decreasing ZVC particle *** optimal pH of the reaction system was *** mechanism investigation showed that Cu+generated by ZVC corrosion was the main reducing agent for the activation of 02 to produce ROS.-OH was identified as the only ROS formed during the degradation of PNP and its production pathway was the double-electron activation of O2(O2→H2 O2→·OH).In this process,STPP did not only promote the release of Cu+through its complexation,but also promoted the production of OH by reducing the redox potential of Cu2+/Cu+.In addition,we could initiate and terminate the reaction by controlling the *** pH8.1,the reaction was *** was recycled to continuously promote the corrosion of ZVC and O2 activation as long as the pH was<*** study provided a new and efficient way for O2 activation and organic contaminants removal.

关键词： Sodium tripolyphosphate Zero valent copper corrosion Oxygen activation pH control