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Journal of University of Science and Technology Beijing 2006年第4期13卷 380-384页

作者： wenli guo Juan Wang Tongxiang Liang Institute of Nuclear Energy Technology Tsinghua University Beijing 100084 China

Dispersion copolymerization of styrene with polyethylene glycol 200-dimethacrylae as the cross-linking agent was completed by using poly（N-vinyl pyrrolidone） and 2,2-azo-bisisobutyronitrile as the steric stabilizer and initiator, respectively. Crosslinked copolymeric microspheres were prepared directly by the one-step method of dispersion copolymerization. The effects of the content of polyethylene glycol 200-dimethacrylae on the particle morphology and the copolymerization rate were investigated. It shows that the crosslinking agent plays an important role in the particle morphology and the system stability. When the content of crosslinking reached 2.5wt%, the floriated particles were obtained.

关键词： polystyrene microsphere dispersion polymerization crosslinking agent

Disruption of iron homeostasis and resultant health effects upon exposure to various environmental pollutants:A critical review

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Journal of Environmental Sciences 2015年第8期27卷 155-164页

作者： wenli guo Jie Zhang Wenjun Li Ming Xu Sijin Liu State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences School of Stomatology Wuhan University

Environmental pollution has become one of the greatest problems in the world, and the concerns about environmental pollutants released by human activities from agriculture and industrial production have been continuously increasing. Although intense efforts have been made to understand the health effects of environmental pollutants, most studies have only focused on direct toxic effects and failed to simultaneously evaluate the long-term adaptive, compensatory and secondary impacts on health. Burgeoning evidence suggests that environmental pollutants may directly or indirectly give rise to disordered element homeostasis, such as for iron. It is crucially important to maintain concerted cellular and systemic iron metabolism. Otherwise, disordered iron metabolism would lead to cytotoxicity and increased risk for various diseases, including cancers. Thus, study on the effects of environmental pollutants upon iron homeostasis is urgently needed. In this review, we recapitulate the available findings on the direct or indirect impacts of environmental pollutants, including persistent organic pollutants（POPs）, heavy metals and pesticides, on iron homeostasis and associated adverse health problems. In view of the unanswered questions, more efforts are warranted to investigate the disruptive effects of environmental pollutants on iron homeostasis and consequent toxicities.

关键词： Persistent organic pollutants Heavy metals Organophosphate pesticides Iron homeostasis Iron diseases Hepcidin Ferroportin

A study of function mechanism of hemxamethyl tetra-amine in gelation process of uranium

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Rare Metals 2006年第z1期25卷 343-346页

作者： guo wenli LIANG Tongxiang ZHAO Xingyu HAO Shaochang FU Xiaoming Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China

The UO2 ceramic microspheres are the most important materials in the spherical fuel elements for high temperature reactor (HTR). A process for preparation of UO2 kernels known as total gelation process of uranium (TGU) was developed as the production process of 10 mW HTR at Tsinghua University. The TGU process is based on the traditional sol-gel process, external gelation process and internal gelation process of uranium (EGU and IGU), which implies that the gelation action is initiated both by ammonia out of the gel particles and hemxamethyl tetra-amine (HMTA) inside the gel particles. The gelation behavior and the properties of uranium microspheres were investigated of the solution with and without HMTA. It is observed that good spherical particles can be obtained without HMTA in the sol, which indicates a more controllable and industrialized route will be set up. Contrasts between this route and the traditional EGU were also listed.

关键词： gelation process of uranium high temperature reactor (HTR) UO2 microsphere

Preparing UO_2 kernels by gelcasting

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Nuclear Science and Techniques 2009年第2期20卷 124-128页

作者： guo wenli LIANG Tongxiang ZHAO Xingyu HAO Shaochang LI Chengliang Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China

A process named gel-casting has been developed for the production of dense UO2 kernels for the high-temperature gas-cooled *** with the sol-gel process,the green microspheres can be got by dispersing the U3O8 slurry in gelcasting process,which means that gelcasting is a more facilitative process with less waste in fabricating UO2 *** UO2 kernels with the size of 500 μm,O/U≤2.01,density of 10.70 g·cm-3 were obtained by gel-casting process followed by heat treatment.

关键词：凝胶注模成型内核高温气冷实验堆铀成型过程溶胶凝胶法 U3O8 高密度

Climatic change features of fog and haze in winter over North China and Huang-Huai Area

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Science China Earth Sciences 2015年第5期58卷 1370-1376页

作者： YIN ZhiCong WANG HuiJun guo wenli Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing Meteorology Bureau Climate Change Research Center Chinese Academy of Sciences

This paper revealed the climatic change characteristics of fog and haze of different levels over North China and Huang-Huai area(NCHH).It was found that the haze-prone period has changed from winter into a whole year,and the haze days(HD)in winter have increased *** foggy days(FD)are half of *** are little difference on the number of days and trends of fog at various *** HD and FD show no obvious positive correlation until the *** has larger spatial scale,showing more in the south than in the *** occurs mainly around large cities with a discrete *** the background of weakened East Asian Winter Monsoon(EAWM)and sufficient particulate matter,the negative correlation between haze and wind speed is weakened,but the positive correlation between haze and moisture conditions(precipitation and humidity)is significantly *** recent years,small wind and variability appear ***,as the stable source and strong moisture absorption of the aerosol particles,the moisture condition becomes one key control factor in the haze,especially wet haze with less *** contrast,the FD presents a stable positive correlation with precipitation and relative humidity,but has no obvious negative correlation with wind speed.

关键词： haze fog visibility east asian winter monsoon weather conditions

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The role of surface charges in the blinking mechanisms and quantum-confined Stark effect of single colloidal quantum dots

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Nano Research 2022年第8期15卷 7655-7661页

作者： Jialu Li Dengfeng Wang guofeng Zhang Changgang Yang wenli guo Xue Han Xiuqing Bai Ruiyun Chen Chengbing Qin Jianyong Hu Liantuan Xiao Suotang Jia State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser SpectroscopyCollaborative Innovation Center of Extreme OpticsShanxi UniversityTaiyuan 030006China

The two frequently observed phenomena,photoluminescence(PL)blinking and quantum-confined Stark effect(QCSE)-induced spectral diffusion,are not conducive to the applications of colloidal quantum dots(QDs).It remains elusive how these two phenomena are linked to each *** the potential link between blinking and QCSE could facilitate the adoption of appropriate strategies that can simultaneously suppress both PL blinking and spectral *** this work,we investigated the blinking mechanism and QCSE of single CdSe/CdS/ZnS QDs in the presence of positive and negative surface charges using single-dot PL *** found that the negative surface charges can simultaneously suppress PL blinking and spectral diffusion of single *** the other hand,the positive surface charges could change the blinking mechanisms of QDs from Auger-blinking to band-edge carrier(BC)-*** types of QCSE were observed,and a significant QCSE-induced spectral broadening of 5.25 nm was measured,which could be attributed to the hopping of surface charges between different surface-trap *** on these findings,several theoretical models are proposed to explain various phenomena observed.

关键词： single quantum dots blinking mechanisms quantum-confined Stark effect surface charges surface traps

Rational Engineering of Secondary Metabolic Pathways in a Heterologous Host to Enable the Biosynthesis of Hibarimicin Derivatives with Enhanced Anti-Melanomic Activity

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Engineering 2024年第7期38卷 113-123页

作者： Xiangyang Liu Fei-Peng Zhao Tian Tian Wei-Chen Wang Zaizhou Liu Qiang Zhou Xian-Feng Hou Jing Wang wenli guo Shuangjun Lin Yasuhiro Igarashi Gong-Li Tang State Key Laboratory of Chemical Biology Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China State Key Laboratory of Microbial Metabolism&Joint International Research Laboratory on Metabolic and Developmental Sciences School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China Biotechnology Research Center Toyama Prefectural UniversityImizu 939-0398Japan

A 61-kb biosynthetic gene cluster(BGC),which is accountable for the biosynthesis of hibarimicin(HBM)B from Microbispora rosea *** TP-A0121,was heterologously expressed in Streptomyces coelicolor M1154,which generated a trace of the target products but accumulated a large amount of shunt *** on rational analysis of the relevant secondary metabolism,directed engineering of the biosynthetic pathways resulted in the high production of HBM B,as well as new HBM derivates with improved antitumor *** results not only establish a biosynthetic system to effectively synthesize HBMs-a class of the largest and most complex Type-Ⅱpolyketides,with a unique pseudo-dimeric structure-but also set the stage for further engineering and deep investigation of this complex biosynthetic pathway toward potent anticancer drugs.

关键词： Hibarimicin Biosynthesis Heterologous expression Biosynthetic gene cluster Rational engineering Type-II polyketide

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HCI在个性化数字图书馆界面设计中的应用

图书馆杂志 2008年第3期27卷 48-53页

作者：郭文丽中国科学院研究生院中国科学院国家科学图书馆北京100080

用户界面的友好性对于数字图书馆的服务质量有着重要的影响作用。以一个个性化数字图书馆界面的设计为例,分析如何把 Human-Computer Interaction(HCI)的概念和技术应用于数字图书馆界面的设计中。介绍了相关研究背景、设计原则、用户... 详细信息

用户界面的友好性对于数字图书馆的服务质量有着重要的影响作用。以一个个性化数字图书馆界面的设计为例,分析如何把 Human-Computer Interaction(HCI)的概念和技术应用于数字图书馆界面的设计中。介绍了相关研究背景、设计原则、用户与任务分析以及系统设计模型。

关键词：人机交互数字图书馆用户界面个性化

Towards Developing a CAS E- Journal Archiving System

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现代图书情报技术 2008年第1期 13-20页

作者： ZHANG ZHIXIONG WU ZHENXIN ZHAO QI LIU JIANHUA guo wenli XU JIAN National Science Library Chinese Academy of Sciences China Graduate University of Chinese Academy of Sciences China

As a part of NSTL proposed long-term preservation of digital information network, the National Science Library of CAS (NSLC) constructed a long-term preservation system of electronic journals called CAS E-Journal Archiving System, which was based on OAIS and adapted Fedora as the fundament system. The system chose a certain amount of electronic journals as pilot resources. Through three major system functional components comprising ingest, preservation management and data dissemination, the system took the long-term preservation of digital objects function into practice. The system is designed to be open and scalable. It realized digital objects management and lifecycle management. In this paper we describe the design of the system, and the issues we have learnt about long-term preservation.

关键词：电子期刊存档系统中国科学院国家科学图书馆数字资源长期保存系统

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溶胶-共沉淀法制备堇青石纳米粉体

稀有金属材料与工程 2005年第z1期34卷 114-116页

作者：郭文利徐廷献黄平国家教育部先进陶瓷与加工技术重点实验室天津大学材料学院天津300072 国家教育部先进陶瓷与加工技术重点实验室天津大学材料学院天津300072 国家教育部先进陶瓷与加工技术重点实验室天津大学材料学院天津300072

以结晶氯化铝(AlCl3·6H2O)、结晶氯化镁(MgCl2·6H2O)和正硅酸乙酯(TEOS)为原料,配成溶胶之后,控制溶胶的pH值,加入氨水进行共沉淀得到氢氧化物胶体.对共沉淀粉末进行热处理,在1300℃得到了堇青石超细粉体(平均粒径20 nm～50 nm).研究... 详细信息

以结晶氯化铝(AlCl3·6H2O)、结晶氯化镁(MgCl2·6H2O)和正硅酸乙酯(TEOS)为原料,配成溶胶之后,控制溶胶的pH值,加入氨水进行共沉淀得到氢氧化物胶体.对共沉淀粉末进行热处理,在1300℃得到了堇青石超细粉体(平均粒径20 nm～50 nm).研究了溶胶-共沉淀法制备MAS粉体的工艺参数对粉体性能的影响,为溶胶-共沉淀包覆其它陶瓷粉料(Si3N4)提供可靠的实验依据.用综合热分析仪对沉淀粉料进行DTA和TG分析,对煅烧料进行XRD分析,电子透射电镜观察其形貌以及EDAX能谱分析,采用压汞仪测定比表面.

关键词：溶胶-共沉淀法堇青石超细粉体包覆