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Electrical characterization and measurements of SiN thin films on crystalline silicon substrates by PECVD after RTP

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Electrical characterization and measurements of SiN thin fil...

第二届晶体硅太阳电池及材料科学与技术国际研讨会

作者： Bingyan Ren1,Bei Guo1’ 2,Yan Zhang1’ 2,Bing Zhangl’ 2, Hongyuan Li1,Xudong Li 2 School of Material Science and Engineering,Hebei university of Technology,300130, I~an Jin,China Beijing Solar Energy research Institute,3# HuaYuan Road,HaiDian District Beiiing 100083,China

In this work silicon nitride(SIN)films were deposited on p-type mono-crystalline silicon substrates using SiH/NH by plasma enhanced chemical vapour deposition (PECVD).We used two kinds of subtract: the one is p-type(100)mono-crystalline silicon wafers with the following characteristics: 4-inch diameter,500μm thickness,and 10～20Ωcm resistivity,a Buehler diamond saw-cutter (model ISO-9001) was employed to cut the Si substrates to 2×2cm;the other is multi-crystalline silicon wafer with the following characteristics: 100×100cm,330±40μm,0.5～2.0Ωcm *** SiN films on silicon substrate have better surface passivation properties and better anti-reflection than the other material films,especially the SiN films on multi-crystalline silicon substrates have taken effect the bulk ***,these samples with the SiN film were prepared under different annealing ***,we want to fully understand hydrogen behavior during deposition and following annealing,meanwhile,the effective carrier lifetimeτ and the other electrical property of these samples with the SiN film were compared and contrasted with before and after annealing,these were also our focal point in this *** sample prepared after PECVD are submitted to rapid thermal annealing in N at 300～1100℃for different time intervals of *** characterization and the electrical property of the sample were measured using Quasi-steady state Photoconductance Decay (QSSPCD),Spectral ellipsometry,X-ray Photoelectric spectrum (XPS),Infrared Absorption Spectroscopy (IR),UV-Vis and Scanning Electron Microscope(SEM),then we can gain these experimental parameters:the refractive index n,the Si/N ratio,the hydric content of SiN film, and the situation of the surface *** measuring the passivation results of hydrogen plasma and SiN thin film,we found an evident improvement of minor carrier lifetime in polycrystalline silicon after hydrogen plasma treatment,although it has little to do with the anne

关键词： SiN film PECVD crystalline silicon RTP

Activation of KCNQ potassium channels by small chemical moleculars

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Activation of KCNQ potassium channels by small chemical mole...

中国神经科学学会第九届全国学术会议暨第五次会员代表大会

作者： Zhaobing GAO~1,Min LI~(1,2) 1 state Key laboratory of Drug research,Shanghai Institute of Materia Medica,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,555 Zu Chong Zhi Road,Zhangjiang Hi-Tech Park,Shanghai 201203,China 2 Department of Neuroscience,High Throughput Biology Center and Johns Hopkins Ion Channel Center,School of Medicine,Johns Hopkins university,Baltimore,Maryland 21205

＜正＞KCNQ potassium channels play a critical role in controlling membrane *** a typical voltagegated ion channels（Kv）,KCNQ channels undergo closed to open transitions by sensing transmembrane potential changes and mediate inhibitory potassium *** of KCNQ channel activity as results of genetic mutation is causal to a variety of human diseases including epilepsy,arrhythmia and ***,discovery of small compounds to activate voltage-gated ion channels is an important strategy for clinical intervention in human diseases caused by membrane hyperexcitability,including anxiety,epilepsy,arrhythmia and neuropathic *** the binding of these molecules induces a conformational change leading to the opening of these channels,there is also a considerable conceptual interest in understanding the molecular basis of these "gain of a function" *** molecule activators of cation channels are rare;however,several novel compounds have been identified for KCNQ potassium ***,we reported two new molecules which potentiate either cardical or neuronal KCNQ channels and identified molecular determinants for their activity,which provide exciting insights into activation of voltage-gated channels by small molecuars.

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A SUBSET APPROACH FOR ANALYSIS OF EXPERIMENTS ON THE RELATIONSHIP BETWEEN SPECIES DIVERSITY AND ECOSYSTEM PRODUCTIVITY

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A SUBSET APPROACH FOR ANALYSIS OF EXPERIMENTS ON THE RELATIO...

第六届全国生物多样性保护与持续利用研讨会

作者： ZHANG Quanguo and ZHANG Dayong (Ministry of Education Key laboratory for Biodiversity Science and Ecological Engineering & Institute of Ecology,Beijing Normal university,Beijing 100875)

Recent experiments that demonstrated a positive effect of species diversity on primary productivity have generated both considerable interest and *** methods have been developed for analyzing and interpreting the diversity-productivity *** we propose a new"subset approach"to directly test the existence of complementarity effect at any diversity *** analyzed whether each multi-species combination performs better than its subset combinations(the less diverse combinations comprised by its component species),and test the existence of complementarity effect at different diversity *** subset approach and several other methods(ANOVAs, overyielding index,and"additive partition") were applied to data from an aquatic microcosm *** this experiment,we used five algal species,cultured in all possible combinations,to create a species richness *** analysis implied that species diversity had a progressive stronger positive effect on productivity through time,but the selection effect became less ***"additive partition"method showed positive selection and complementarity *** selection effects exceeded the complementarity effect at the early stage of the experiment;but the two types of mechanisms contributed equally at the later *** overyielding test found small proportion of mixtures yielded more than the most productive monoculture of component species,and offered little evidence for niche complementarity ***"subset approach"analysis proved significant complementarity effect at 2-species diversity level at some time points during the experiment;but rejected the existence of complementarity at higher diversity levels.

关键词： subset approach ANOVAs overyielding additive partition microcosm

TiO_2/Ag光催化膜降解特种印刷工业废水的研究

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水处理技术 2002年第6期28卷 323-328页

作者：崔鹏徐南平时钧南京化工大学膜科学技术研究所江苏省化学工程与技术重点实验室合肥工业大学化工学院安徽合肥230009

采用溶胶 -凝胶法制备活性炭负载的 Ti O2 /Ag光催化膜 ,利用 SEM、EDS、XPS等方法对活性炭表面 Ti O2 /Ag的成膜性、主要元素及价态等进行表征。通过对特种印刷工业废水的光催化降解性能研究 ,确定了光催化剂用量、不同起始浓度、不同... 详细信息

采用溶胶 -凝胶法制备活性炭负载的 Ti O2 /Ag光催化膜 ,利用 SEM、EDS、XPS等方法对活性炭表面 Ti O2 /Ag的成膜性、主要元素及价态等进行表征。通过对特种印刷工业废水的光催化降解性能研究 ,确定了光催化剂用量、不同起始浓度、不同气量对光催化性能的影响 ;

关键词： TiO2/Ag光催化膜印刷工业光催化剂二氧化钛印刷废水降解废水处理

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Lorenz混沌系统的近似有限时间稳定控制

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物理学报 2011年第10期60卷 15-23页

作者：赵建利王京魏伟北京科技大学高效轧制国家工程研究中心北京100083

针对Lorenz混沌系统,研究其有限时间稳定控制问题.考虑系统存在不确定非线性,提出一种可使受控Lorenz系统实现近似有限时间稳定的控制方法.改进并设计一种扩张状态观测器,解决了受控Lorenz系统中不确定非线性未知问题.通过引入奇异扰动... 详细信息

针对Lorenz混沌系统,研究其有限时间稳定控制问题.考虑系统存在不确定非线性,提出一种可使受控Lorenz系统实现近似有限时间稳定的控制方法.改进并设计一种扩张状态观测器,解决了受控Lorenz系统中不确定非线性未知问题.通过引入奇异扰动性理论,分析了闭环系统的近似有限时间稳定性.仿真实验结果验证了该控制方法及扩张状态观测器的有效性.

关键词： Lorenz混沌系统近似有限时间稳定扩张状态观测器奇异扰动

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Incremental Multi-Label Learning with Active Queries

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Journal of Computer Science & Technology 2020年第2期35卷 234-246页

作者： Sheng-Jun Huang Guo-Xiang Li Wen-Yu Huang Shao-Yuan Li College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Key laboratory of Pattern Analysis and Machine Intelligence Ministry of Industry and Information Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing University Nanjing 210023China

In multi-label learning,it is rather expensive to label instances since they are simultaneously associated with multiple ***,active learning,which reduces the labeling cost by actively querying the labels of the most valuable data,becomes particularly important for multi-label learning.A good multi-label active learning algorithm usually consists of two crucial elements:a reasonable criterion to evaluate the gain of querying the label for an instance,and an effective classification model,based on whose prediction the criterion can be accurately *** this paper,we first introduce an effective multi-label classification model by combining label ranking with threshold learning,which is incrementally trained to avoid retraining from scratch after every *** on this model,we then propose to exploit both uncertainty and diversity in the instance space as well as the label space,and actively query the instance-label pairs which can improve the classification model *** experiments on 20 datasets demonstrate the superiority of the proposed approach to state-of-the-art methods.

关键词： active learning multi-label learning uncertainty diversity

两段提升管FCC新工艺改善催化裂化产品分布研究

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石油大学学报（自然科学版） 2002年第5期26卷 77-79,83页

作者：李毅山红红张建芳韩忠祥杜峰石油大学重质油加工国家重点实验室山东东营257061

两段提升管催化裂化新工艺突破常规催化裂化工艺单一依靠调节反应参数来改善产品分布和质量的控制模式 ,在优化外部操作条件的同时 ,在反应内部改变中间产物的油气分压 ,使反应向理想的方向进行。试验结果表明 ,与常规催化裂化工艺相比 ... 详细信息

两段提升管催化裂化新工艺突破常规催化裂化工艺单一依靠调节反应参数来改善产品分布和质量的控制模式 ,在优化外部操作条件的同时 ,在反应内部改变中间产物的油气分压 ,使反应向理想的方向进行。试验结果表明 ,与常规催化裂化工艺相比 ,这种内外协调、优化控制的新工艺可使柴油产率提高 8个百分点 ,汽油产率仅减少1个百分点 ,而干气产率下降 1个百分点 ,重油产率下降 8个百分点 ,轻油选择性提高 10个百分点以上 ,大大改善了催化裂化产品的分布 ,达到了提高轻油收率、降低干气和重油产率的目的。

关键词：两段提升管 FCC 新工艺催化裂化产品分布柴油轻油收率

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A taxonomic re-assessment in the Chinese Bupleurum(Apiaceae):Insights from morphology,nuclear ribosomal internal transcribed spacer,and chloroplast(trnH-psbA,matK) sequences

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Journal of Systematics and Evolution 2011年第6期49卷 558-589页

作者： Chang-Bao WANG Xiang-Guang MA Xing-Jin HE(College of Life Science,Sichuan university,Chengdu 610064,China) (College of Life Science Sichuan University Chengdu 610064 China)

As one of the big genera in Apiaceae,Bupleurum *** received considerable attention from plant ***,there are still many gaps in our knowledge of this genus,especially of those species endemic to China that have often been excluded from previous *** spite of a few recent studies on the phylogeny and classification of the Chinese Bupleurum,the most essential problem of species delimitation still remains *** re-evaluate the taxonomy of the Chinese Bupleurum using morphological and molecular *** observations of living plants growing the field and herbarium specimens were made to understand the morphological variation and to ensure species identification for the molecular *** analyses were carried out on sequence data of nuclear ribosomal internal transcribed spacer(nrITS),trnH-psbA,and matK,using parsimony and Bayesian approaches to evaluate species *** of both nrITS and combined datasets of the three regions revealed the following results:(i)the Chinese Bupleurum species were divided into two major lineages;and(ii)most species were well defined,but some traditional inter-and infraspecific relationships were not *** results,along with the results of previous works support that the Chinese Bupleurum species were derived from two different lineages and should be placed in Neves and Watson’s subgenus *** detailed taxonomic re-assessment of several Chinese species resulted in new taxonomic recombinations with rank changes for three species:Bupleurum tenerum,***,and ***;new combination for one variety,*** ***;and the description of one variety and one species,*** *** and ***.

关键词： Chinese Bupleurum chloroplast sequences(trnH-psbA matK) morphology nrITS phylogenetic analyses taxonomy and new species.

A Clustering Algorithm towards Microblogs based on Vector Space Model

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A Clustering Algorithm towards Microblogs based on Vector Sp...

2012 National Conference on Information Technology and Computer Science

作者： Guoyou Chen Institute of Command Automation,PLA university of Science and Technology,Nanjing,China Jiajia Miao 1,2 1) Institute of Command Automation,PLA university of Science and Technology,Nanjing,China 2) Key laboratory of C4ISR Technology,National university of Defense Technology,Changsha,China Handong Mao Key laboratory of C4ISR Technology,National university of Defense Technology,Changsha,China Le Wang Key laboratory of C4ISR Technology,National university of Defense Technology,Changsha,China Siyu Jiang The post-doctoral workstation of the 73111 army,Xiamen,China

Weibos have become wildly popular in China in recent years,and state media reports that there are more than 300 million registered *** "Real Name" Policy[1] requires all users on Chinese weibo websites to register with the name that corresponds with their government issued ID *** the rapid development of the web,the research of consensus encounters new problems and *** a practical method for large-scale text clustering,instant messaging,text content analysis features,and find or track the social hot *** the file,which is not suitable for very common clustering algorithm? A new method is proposed of the named MVSM synthesis microblogging dialogue,but also enriched the words of the vector is not included in the text of the blog,but existing content is closely *** vector space this MVSM perform the dialogue,k-means *** on public datasets show better,MVSM than traditional k-means and kmeans algorithm into two.

关键词： microblogs clustering k-means vector space model