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Enantioselective induction of oxidative stress by acetofenate in rat PC12 cells

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Journal of Environmental Sciences 2010年第12期22卷 1980-1986页

作者： Ling Li Fen Hu Cui wang xuedong wang Research Center of Environmental Science College of Biological and Environmental Engineering Zhejiang University of Technology Hangzhou 310032 China School of Environmental Science and Public Health Wenzhou Medical College Wenzhou 325035 China

In a non-chiral environment, the enantiomers of a racemate possessed the identical physico-cbemical properties, but in the biological systems they possessed different activities. Considering that the involvement of oxidative damage has been implicated in the toxicities of various pesticides, this study investigated the possibility of enantioselective oxidative stress and cytotoxicity induction by acetofenate （AF） which contains an asymmetrical center on PC12 cells. The results of the cytotoxicity assay indicated that S-（＋）-AF presented more toxic effects than R-（-）-AF and （＋）-AF. It also demonstrated that S-（＋）-AF possessed the strongest effects in induction of reactive oxygen species （ROS） production, decrease in superoxide dismutase （SOD） and catalase （CAT） activities, and increase in malondialdehyde （MDA） level. These results suggested that AF and its enanfiomers could induce enantioselecfive cytotoxicity in PC12 cells mediated by oxidative stress. Therefore, the assessment in environmental safety and new chiral pesticide development should consider enantioselectivity.

关键词： chiral organochlorine pesticides acetofenate enantioselectivity cytotoxicity oxidative stress

Biodegradation of triclosan and triclocarban in sewage sludge during composting under three ventilation strategies

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Frontiers of Environmental Science & Engineering 2019年第3期13卷 137-146页

作者： Bao Yu Guodi Zheng xuedong wang Min wang Tongbin Chen Center for Environmental Remediation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China College of Resources and Environment University of Chinese Academy of Sciences Beijing 100049 China College of Resource Environment and Tourism Capital Normal University Beijing 100048 China

Triclosan (TCS) and triclocarban (TCC) are widely used in home and personal care products as antimicrobial agents. After these products are used, TCS and TCC enter the terrestrial environment and pose a great risk to humans and animals. In this research, the biodegradation of TCS and TCC was investigated during sewage sludge composting with ventilation rates of 10& 92, and 79 m^3/min. TCS and TCC were mainly biodegraded in the mesophilic and thermophilic phases, and the biodegradation rates improved with an increase in ventilation. After sewage sludge was composted for 16 days with forced ventilation (108 m^3/min), the concentration of TCS decreased from 497.4 to 214.5 μg/kg, and the concentration of TCC decreased from 823.2 to 172.7 μg/kg. The biodegradation rates of TCS and TCC were 65.2% and 83.1%, respectively. However, after the sewage sludge was stacked for 16 days, the biodegradation rates of TCS and TCC were only 17.0% and 18.2%, respectively. The environmental risks of TCS and TCC in the sewage sludge piles significantly decreased after composting. In the sludge pile with a ventilation rate of 108 m/min, the RQ values of TCS and TCC decreased from 8.29 and 20.58 to 3.58 and 4.32 after composting for 16 days, respectively. There is still a high risk if the sludge compost is directly used as a culture substrate. Nevertheless, the environmental risk could be decreased distinctly if a reasonable quantity of sludge compost is applied to land to ensure an RQ of< 1 for TCS and TCC.

关键词： Sewage sludge Compost Triclosan Triclocarban Ventilation Risk assessment

Centrifugal casting processes of manufacturing in situ functionally gradient composite materials of Al-19Si-5Mg alloy

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Rare Metals 2009年第4期28卷 405-411页

作者： XIE Yong LIU Changming ZHAI Yanbo wang Kai LING xuedong College of Materials Science and Engineering Chongqing University Chongqing 400045 China

Cylindrical components of in situ functionally gradient composite materials of Al-19Si-5Mg alloy were manufactured by centrifugal casting. Microstructure characteristics of the manufactured components were observed and the effects of the used process factors on these characteristics were analyzed. The results of observations shows that, in thickness, the components possess microstructures accumulating lots of Mg2Si particles and a portion of primary silicon particles in the inner layer, a little MgzSi and primary silicon particles in the outer layer, and without any Mg2Si and primary silicon particle in the middle layer. The results of the analysis indicate that the rotation rate of centrifugal casting, mould temperature, and melt pouring temperature have evidently affected the accumulation of the second phase particles. Also, the higher the centrifugal rotation rate, mould temperature, and melt pouring temperature are, the more evident in the inner layer the degree of accumulation of Mg2Si and primary silicon particles is.

关键词： centrifugal casting Al-Si-Mg alloys Mg2Si particles silicon particles functionally gradient composites

Modeling of acute cadmium toxicity in solution to barley root elongation using biotic ligand model theory

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Journal of Environmental Sciences 2016年第4期28卷 112-118页

作者： xuedong wang Mingyan Wu Jingxing Ma Xiaolin Chen Luo Hua The Key Lab of Resource Environment and GIS College of Resource Environment and TourismCapital Normal University

Protons（H^＋）as well as different major and trace elements may inhibit cadmium（Cd）uptake in aquatic organisms and thus alleviate Cd ***,little is known about such interactions in soil *** this study,the independent effects of the cations calcium（Ca^2＋）,magnesium（Mg^2＋）,potassium（K^＋）,H^＋ and zinc（Zn^2＋）on Cd toxicity were investigated with 5-day long barley root elongation tests in nutrient *** tested concentrations of selected cations and trace metal ions were based on the ranges that occur naturally in soil pore *** toxicity of Cd decreased with increasing activity of Ca^2＋,Mg^2＋,H^＋and Zn^2＋,but not K^＋.Accordingly,conditional binding constants were obtained for the binding of Cd^2＋,Ca^2＋,Mg^2＋,H^＋,and Zn^2＋ with the binding ligand：log K（CdBL）5.19,logK（CaBL）2.87,logK（MgBL）2.98,logK（HBL）5.13 and logK（ZnBL）5.42,***,it was calculated that on average 29% of the biotic ligand sites needed to be occupied by Cd to induce a 50% decrease in root *** the estimated constants,a biotic ligand model was successfully developed to predict the Cd toxicity to barley root elongation as a function of solution *** feasibility and accuracy of its application for predicting Cd toxicity in soils were discussed.

关键词： Cadmium Biotic ligand model (BLM) Toxicity Barley

Filament growth dynamics in solid electrolyte-based resistive memories revealed by in situ TEM

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Nano Research 2014年第7期7卷 1065-1072页

作者： Xuezeng Tian Lifen wang Jiake Wei Shize Yang Wenlong wang Zhi Xu xuedong Bai Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 7 O0190 China

Solid electrolyte based-resistive memories have been considered to be a potential candidate for future information technology with applications in non-volatile memory, logic circuits and neuromorphic computing. A conductive filament model has been generally accepted to be the underlying mechanism for the resistive switching. However, the growth dynamics of such conductive filaments is still not fully understood. Here, we explore the controllability of filament growth by correlating observations of the filament growth with the electric field distribution and several other factors. The filament growth behavior has been recorded using in situ transmission electron microscopy. By studying the real- time recorded filament growth behavior and morphologies, we have been able to simulate the electric field distribution in accordance with our observations. Other factors have also been shown to affect the filament growth, such as Joule heating and electrolyte infrastructure. This work provides insight into the controllable growth of conductive filaments and will help guide research into further functionalities of nanoionic resistive memories.

关键词： resistive switching conductive filaments in situ transmissionelectron microscope real-time observation computer simulation

Degradation of chlorpyrifos alone and in combination with chlorothalonil and their effects on soil microbial populations

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Journal of Environmental Sciences 2008年第4期20卷 464-469页

作者： CHU Xiaoqiang FANG Hua PAN xuedong wang Xiao SHAN Min FENG Bo YU Yunlong Department of Plant Protection College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 China

In practice, pesticides are usually applied simultaneously or one after another for crop protection, and this type of pesticide application often leads to a combined contamination of pesticide residues in the soil environment. A laboratory study was conducted to investigate the influence of chlorothalonil on chlorpyrifos degradation and its effects on soil bacterial, fungal, and actinomycete populations. Under the experimental conditions here, the half-lives of chlorpyrifos alone, and in combination with chlorothalonil, at the recommended and double dosages, were measured to be 3.24, 2.77, and 2.63 d, respectively. Chlorpyrifos degradation was not significantly altered by its combination with chlorothalonil. However, the inhibitory effect of chlorpyrifos on soil microorganisms was increased by its combination with chlorothalonil, and the increase was related to the levels of chlorothalonil added. Compared to those in the controls, the populations of bacteria, fungi, and actinomycetes were significantly reduced by 44.1%, 61.1%, and 72.8%, respectively, on the first day after treatment （DAT） by chlorpyrifos alone. With the addition of chlorothalonil, the inhibition was increased to 55.2%, 79.3%, and 85,8% at the recommended dosage, and 86.0%, 94.1%, and 90.8% at the double dosage, at one DAT, respectively. The results suggested that combined effects should be taken into account to assess the actual impacts of pesticide applications.

关键词： pesticide soil microorganism chlorpyrifos chlorothalonil combination

“国际共产主义运动史”与“世界社会主义”的关系--访王学东教授

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社会主义研究 2018年第6期 31-35页

作者：王学东邓岩中国社会科学院大学山东大学中国人民大学中央编译局中国国际共产主义运动史学会华中师范大学政治与国际关系学院河南财经政法大学公共管理学院

"国际共产主义运动史"与"世界社会主义"的关系是一个十分重要的话题。苏东剧变以后,传统的国际共运史学科受到冲击,"世界社会主义"概念开始被频繁使用,国际共运史学科在越来越多的场合被改称为世界社会主义学科,一度出现了用"世界社会主... 详细信息

"国际共产主义运动史"与"世界社会主义"的关系是一个十分重要的话题。苏东剧变以后,传统的国际共运史学科受到冲击,"世界社会主义"概念开始被频繁使用,国际共运史学科在越来越多的场合被改称为世界社会主义学科,一度出现了用"世界社会主义"替代"国际共运史"的趋势。不过现在看来,这种做法是不可取的。"世界社会主义"与"国际共运史"虽然密切相关,甚至有部分内容相互重合,但是它们的研究对象和研究范围还是有显著区别的,不可等同视之,更不能相互替代。应当用当代世界社会主义来延续或补充国际共运史,而不能用世界社会主义来取代国际共运史。因此,为促进学科发展,有必要从学科建设的角度厘清两者的关系,搞清它们之间的联系与区别。本刊就此问题对我国著名的国际共产主义运动史专家王学东教授进行了专访,以期帮助学界更好地理解"国际共产主义运动史"与"世界社会主义"之间的关系,为相关学科建设和发展提供参考。

关键词：国际共产主义运动史世界社会主义科学社会主义《国际共产主义动运历史文献》

Changes in the physicochemical and protein distribution properties of dough with the wheat oligopeptide incorporation

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Food Bioscience 2023年第2期52卷 255-261页

作者： Hongyan Liu Liuyu Wan Shensheng Xiao Yang Fu xuedong wang Key Laboratory for Deep Processing of Major Grain and Oil Wuhan Polytechnic UniversityMinistry of EducationWuhan430023China Hubei Key Laboratory for Processing and Transformation of Agricultural Products Wuhan Polytechnic UniversityWuhan430023China

The characteristics of the dough modification are crucial to the quality of the final *** study aimed to investigate the effects of wheat oligopeptide(WOP)on dough rheology,physicochemical,and protein distribution *** results showed that WOP increased the viscoelasticity,extensibility,and strength of the *** pasting experiments illustrated that WOP decreased the peak viscosity,breakdown,and setback *** fermentation results showed that WOP significantly increased the fermentation height and gas-holding rate of the ***,the water migration ability of the dough was significantly inhibited after WOP ***,the electrophoresis results further proved that WOP could effectively enhance the aggregation of small molecule *** microstructure results further demonstrated that the dough exhibited more uniform and continuous characteristics with the WOP incorporation,which was consistent with our *** conclusion,WOP has the ability to strengthen the dough network structure,providing a new idea for future modification of dough and its products.

关键词： Wheat oligopeptide Dough modification Physicochemical characteristics Gluten network

FAILURE ANALYSIS AND INSPECTION OF CRACKING OF IN-SERVICE CATALYTIC REGENERATOR

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Chinese Journal of Mechanical Engineering 2002年第2期15卷 167-172页

作者： Chen xuedong Guan Weihe Chen Wenhu Yao Zuoquan Hefei General Machinery Research Institute, Hefei 230031, ChinaGu xuedong wang Zhaowei Shanghai Gaoqiao Petrochemical Company Shanghai Gaoqiao Petrochemical Company Zuoquan Hefei General Machinery Research Institute Hefei 230031

The special subject 'research on life prediction technology of important in-service pressure' mainly analyzes the failure mechanism of large-sized important and criticalin-service pressure vessels under the action of working medium and investigates safety assessmentand life prediction technology with a view to enhance the operation reliability of in-servicepressure vessels in China. Based on a series of accident investigation and test & measuringresearch, the cause of cracking of catalytic regenerator is analyzed and the in-line non-destructiveexamination method and failure prevention measures for the cracking of catalytic regenerator areproposed.

关键词： In-service catalytic regenerator Crack Failure analysis Examination