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Optimization of electrocatalytic properties of NiMoCo foam electrode for water electrolysis by post-treatment processing

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Rare Metals 2015年第11期34卷 802-807页

作者： Jian-Wei Wang Yue-Fa Wang Jing-guo Zhang yan-Lin Yu Ge-Ge Zhou Lei Cheng Lin-Shan Wang Z.Zak Fang State Key Laboratory of Nonferrous Metals and Processes General Research Institute for Nonferrous Metals GRIPM Advanced Materials Co. Ltd General Research Institute for Nonferrous Metals Department of Metallurgical Engineering University of UtahSalt Lake City

Hydrogen is a potential alternative to fossil fuels in coping with the increased global energy demand,and water electrolysis is an attractive approach for H2production. Nickel–molybdenum–cobalt（Ni Mo Co） foam electrodes used for water electrolysis were prepared by the electrodeposition method, and the influence of heat treatments on the surface structure of Ni Mo Co foam electrodes,mechanical properties, and electrochemical performance of the synthesized electrodes was investigated in order to optimize the post-treatment processes. The residual carbon in the surface of the electrode was removed by decarbonization in the atmospheric condition. The carbon content decreases to lower than 200 ×10-6when the temperature exceeds 500 °C. Next, the material is reduced in hydrogen atmosphere from 500 to 1100 °C to remove the surface oxides. As the temperature increases, the surface molybdenum content increases significantly between 500 and 800 °C, the surface grains become coarser, and the tensile strength and elongation increase as well. The lowest polarization overpotential is obtained at 800 °C. Below 800 °C, the electrode is only partially reduced and some black oxide zones are observed on the electrode surface,which leads to the higher polarization overpotential. Thesamples heat-treated at the temperatures of higher than 800 °C show better strength and toughness as well as brighter appearance. However, the surface particle coarsening leads to a decrease in the specific surface area and a higher overpotential.

关键词： Water electrolysis Foam electrode Ni Mo Co Post-tr

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轨控式复合控制导弹制导与控制一体化反步设计

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宇航学报 2013年第1期34卷 79-85页

作者：舒燕军唐硕西北工业大学航天学院西安710072

针对轨控式复合控制导弹制导与控制一体化设计问题,结合动态面反步设计和非线性干扰观测器(NDO)技术,设计了一种基于非线性干扰观测器的制导控制一体化反步控制方法。首先建立了复合控制导弹纵向通道制导控制一体化模型,在此基础上分三... 详细信息

针对轨控式复合控制导弹制导与控制一体化设计问题,结合动态面反步设计和非线性干扰观测器(NDO)技术,设计了一种基于非线性干扰观测器的制导控制一体化反步控制方法。首先建立了复合控制导弹纵向通道制导控制一体化模型,在此基础上分三步设计反步控制器,设计过程中采用了动态面方法,通过引入一阶低通滤波器,得到虚拟控制量的微分,避免了传统反步设计中的"计算膨胀"问题,同时采用NDO对模型不确定性进行估计并加以补偿,实现了对气动系数摄动和目标机动的鲁棒性。基于李亚普诺夫稳定性理论证明了闭环系统所有误差信号最终一致有界。仿真结果表明本文设计的基于非线性干扰观测器的复合控制导弹制导控制一体化反步设计方案的正确性和有效性。

关键词：制导控制一体化反步设计动态面非线性干扰观测器复合控制导弹

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How to manage a task-oriented virtual assistant software project:an experience report

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Frontiers of Information Technology & Electronic Engineering 2022年第5期23卷 749-762页

作者： shuyue LI Jiaqi guo yan GAO Jianguang LOU Dejian yanG yan XIAO Yadong ZHOU Ting LIU Faculty of Electronic and Information Engineering Xi'an Jiaotong UniversityXi'an 710049China Microsoft Research Asia Beijing 100080China

Task-oriented virtual assistants are software systems that provide users with a natural language interface to complete domain-specific *** the recent technological advances in natural language processing and machine learning,an increasing number of task-oriented virtual assistants have been ***,due to the well-known complexity and difficulties of the natural language understanding problem,it is challenging to manage a task-oriented virtual assistant software ***,the management and experience related to the development of virtual assistants are hardly studied or shared in the research community or industry,to the best of our *** bridge this knowledge gap,in this paper,we share our experience and the lessons that we have learned at managing a task-oriented virtual assistant software project at *** believe that our practices and the lessons learned can provide a useful reference for other researchers and practitioners who aim to develop a virtual assistant ***,we have developed a requirement management tool,named SpecSpace,which can facilitate the management of virtual assistant projects.

关键词： Experience report Software project management Virtual assistant Machine learning

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Application of Seismic Azimuth Anisotropic Technique in Fractural Detection of Lower Triassic Jia-2 Reservoir in TNB Area

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石油地球物理勘探 2009年第2期44卷 72-78页

作者： Bi yan-bin Long Sheng-xiang guo Tong-lou Liu Bin SINOPEC Research Institute of Petroleum Exploration and Development Beijing 100083 China South Branch of Exploration and Development of SINOPEC Kunming Yunnan Province 650233 China

低渗致密碳酸盐岩油气藏常与储层中裂缝的发育有着密切关系.在对岩心裂缝发育特征分析和叠前地震资料评价的基础上,本文利用叠前地震方位各向异性技术对TNB构造带嘉二段储层裂缝发育密度和方向进行了区域上的检测,分析了裂缝相对发育带... 详细信息

低渗致密碳酸盐岩油气藏常与储层中裂缝的发育有着密切关系.在对岩心裂缝发育特征分析和叠前地震资料评价的基础上,本文利用叠前地震方位各向异性技术对TNB构造带嘉二段储层裂缝发育密度和方向进行了区域上的检测,分析了裂缝相对发育带的分布规律.研究表明,裂缝发育带在区域上呈现一定的分区性,既受TNB背斜带的宏观控制,又受后期叠加局部构造的影响.研究成果为下一步该地区的井位部署提供了参考依据,同时也展现了叠前地震方位各向异性技术在储层裂缝检测中的应用前景.

关键词：叠前地震数据方位各向异性技术检测下三叠统裂缝检测水库应用碳酸盐岩储层

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A genome-wide analysis of SWEET gene family in cotton and their expressions under different stresses

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Journal of Cotton Research 2018年第2期1卷 12-26页

作者： ZHAO Lanjie YAO Jinbo CHEN Wei LI yan L Youjun guo yan WANG Junyi YUAN Li LIU Ziyang ZHANG Yongshan State Key Laboratory of Cotton Biology Institute of Cotton Research of Chinese Academy of Agricultural Sciences Anyang Institute of Technology University of Saskatchewan

Background： The SWEET （Sugars will eventually be exported transporters） gene family plays multiple roles in plant physiological activities and development process. It participates in reproductive development and in the process of sugar transport and absorption, plant senescence and stress responses and plant-pathogen interaction. However, thecomprehensive analysis of SWEET genes has not been reported in cotton. Results： In this study, we identified 22, 31, 55 and 60 SWEETgenes from the sequenced genomes of Gossypium orboreum, G. rairnondii, G. hirsutum and G. borbadense, respectively. Phylogenetic tree analysis showed that the SWEET genes could be divided into four groups, which were further classified into 14 sub-clades. Further analysis of chromosomal location, synteny analysis and gene duplication suggested that the orthologs showed a good collinearity and segmental duplication events played a crucial role in the expansion of the family in cotton. Specific MtN3_slv domains were highly conserved between Arabidopsis and cotton by exon-intron organization and motif analysis. In addition, the expression pattern in different tissues indicated that the duplicated genes in cotton might have acquired new functions as a result of sub-functionalization or neo-functionalization. The expression pattern of SWEET genes showed that the different genes were induced by diverse stresses. The identification and functional analysis of SWEET genes in cotton may provide more candidate genes for genetic modification. Conclusion： SWEET genes were classified into four clades in cotton. The expression patterns suggested that the duplicated genes might have experienced a functional divergence. This work provides insights into the evolution of SWEETgenes and more candidates for specific genetic modification, which will be useful in future research.

关键词： Gossypium Sugars will eventually be exported transporters (SWEETs) Gene expression patterns Stress

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Effect of 5-azacytidine on the Protein Expression of Porcine Bone Marrow Mesenchymal Stem Cells in vitro

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Genomics, Proteomics & Bioinformatics 2006年第1期4卷 18-25页

作者： Neng-Sheng Ye Rong-Li Zhang yan-Feng Zhao Xue Feng Yi-Ming Wang guo-An Luo Institute of Biomedicine Tsinghua University Beijing 100084 China

Bone marrow-derived mesenchymal stem cells （MSCs） are pluripotent stem cells that show a vital potential in the clinical application for cell transplantation. In the present paper, proteomic techniques were used to approach the protein profiles associated with porcine bone marrow MSCs and investigate the regulation of MSC proteins on the effect of 5-azacytidine （5-aza）. Over 1,700 protein species were separated from MSCs according to gel analysis. Compared with the expression profiling of control MSCs, there were 11 protein spots up-regulated and 26 downregulated in the protein pattern of 5-aza-treated cells. A total of 21 proteins were successfully identified by MALDI-TOF-MS analysis, among which some interesting proteins, such as alpha B-crystallin, annexin A2, and stathmin 1, had been reported to involve in cell proliferation and differentiation through different signaling pathways. Our data should be useful for the future study of MSC differentiation and apoptosis.

关键词： bone marrow mesenchymal stem cells 5-azacytidine two-dimensional gel electrophoresis mass spectrometry proteome

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MgO intercalation and crystallization between epitaxial graphene and Ru(0001)

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Rare Metals 2022年第1期41卷 304-310页

作者： Xue-yan Wang Hui guo Jin-An Shi Yi Biao yan Li Guang-Yuan Han shuai Zhang Kai Qian Wu Zhou Xiao Lin Shi-Xuan Du Cheng-Min Shen Hong-Liang Lu Hong-Jun Gao Institute of Physics and University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100190China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China

Graphene on insulator is the foundation of its practical applications in electronic information ***,fabrication of graphene on insulating substrates suffers from small size and limited quality by direct growth of graphene on dielectric substrates,and the method of transferring graphene onto insulating substrates is not so compatible with the large-scale production in ***,we report the fabrication of high-quality,large-area,single-crystal graphene on crystalline magnesium oxide(MgO),which has a dielectric constant of 7–*** and oxygen are intercalated at the interface of epitaxial graphene/Ru(0001)and form crystalline structure after high-temperature *** graphene/MgO/Ru(0001)sample was characterized by low energy electron diffraction(LEED),scanning tunneling microscopy(STM),X-ray photoelectron spectroscopy(XPS),and scanning transmission electron microscopy(STEM).LEED pattern shows that the magnesium oxide displays crystalline structure,and STM studies show clearly that the top layer is *** characterization of as-intercalated sample demonstrates that the MgO intercalation layer,with a thickness of up to 2.3 nm,has a crystal structure of rock salt MgO,and the out-of-plane crystal orientation is[001].Our work provides a new route for fabrication of graphene on high dielectric constant insulators,which may have potential applications in future electronics.

关键词： crystalline dielectric magnesium

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Detection of PERV by polymerase chain reaction and its safety in bioartificial liver support system

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World Journal of Gastroenterology 2006年第8期12卷 1287-1291页

作者： Hai-Hui Wang Ying-Jie Wang Hong-Ling Liu Jun Liu yan-Ping Huang Hai-Tao guo Yu-Ming Wang Department of Endocrine Diseases. SouthwesternHospital Third Military Medical University Chongqing 400038China Institute of Infectious Diseases Southwestern Hospital Third Military Medical UniversityChongqing 400038 China

AIM： To establish a method detecting porcine endogenous retrovirus （PERV） in China experimental minipigs and to evaluate the safety of PERV in three individuals treated with bioartificial liver support systems based on porcine hepatocytes. METHODS： Porcine hepatocytes were isolated with two-stage perfusion method, then cultured in the bioreactor, which is separated by a semipermeable membrane （0.2μm） from the lumen through which the patients＇ blood plasma was circulated. After posthemoperfusion, patients＇ blood was obtained for screening. Additionally, samples of medium collected from both intraluminal and extraluminal compartments of the laboratory bioreactor and culture supernate in vitro was analyzed. The presence of viral sequences was estimated by polymerase chain reaction （PCR） and reverse transcriptase-polymerase chain reaction （RTPCR）. Finally, the infection of virus in the supernate of common culture was ascertained by exposure to the fetal liver cells. RESULTS： PERV-specific gag sequences were found in the porcine hepatocytes using RT-PCR. and were detected in all samples from the intraluminal, extraluminal samples and culture supernate. However, culture supernatant from primary porcine hepatocytes （cleared of cellular debris） failed to infect human fetal liver cells. Finally, RT-PCR detected no PERV infection was found in the blood samples obtained from three patients at various times post-hemoperfusion. CONCLUSION： The assays used are specific and sensitive, identified by second PCR. PERVs could be released from hepatocytes cultured in bioreactor without the stimulation of mitogen and could not be prevented by the hollow fiber semipermeable membrane, indicating the existence of PERV safety in extracorporeal bioartificial liver support system （EBLSS）.

关键词： PERV Bioartificial liver support systems Polymerase chain reaction

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Isolation and chemotaxonomic significance of stenine- and stemoninine-type alkaloids from the roots of Stemona tuberosa

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Chinese Chemical Letters 2014年第9期25卷 1252-1255页

作者： Rong-Rong Zhang Hai-yan Tian Yi Wu Xiao-Hui Sun Jian-Long Zhang Zhi-guo Ma Ren-Wang Jiang Institute of Traditional Chinese Medicine and Natural Products College of PharmacyJinan University Zhongshan Torch Polytechnic Shenzhen Engineering Laboratory of Lingnan Herbal Resource Development and Application Shenzhen Institute for Drug Control

One new stenine-type alkaloid, tuberostemonine D （1）, together with five known stenine-type alkaloids （2-6） and two known stemoninine-type alkaloids （7 and 8）, were isolated from the roots of Stemona tuberosa. Their structures were elucidated by extensive spectroscopic methods （IR, UV, MS, 1D and 2D NMR）, and the structure of I was further confirmed by X-ray diffraction analysis. First simultaneous isolation ofstenine- and stemoninine-type alkaloids not only added a new chemical type and increased the chemical diversity of Stemona tuberosa, but also provided chemotaxonomic clues for the close relationship between genera Stemona and Stichoneuron, and favored retaining them in the same family.

关键词： Sternona tuberosa Alkaloid Tuberostemonine-type

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Genetic Variation of EPAS1 Gene in Tibetan Pigs and Three Low-Altitude Pig Breeds in China

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Journal of Integrative Agriculture 2014年第9期13卷 1990-1998页

作者： DONG Kun-zhe KANG Ye YAO Na shu guo-tao ZUO Qing-qing ZHAO Qian-jun MA Yue-hui Key Laboratory of Farm Animal Genetic Resources and Utilization Ministry of Agriculture/Institute of Animal Science Chinese Academy of Agricultural Sciences College of Animal Science and Technology Yunnan Agricultural University

Endothelial PAS domain protein 1（EPAS1）, also called hypoxia-inducible factor-2, is a key regulatory factor of hypoxic responses and plays an essential role in high-altitude adaptation in mammalian species. In this study, polymorphisms of EPAS1 were detected in 217 individuals from 2 Tibetan pig populations and 3 low-altitude pig breeds by DNA pooling, PCR-SSCP, PCR-RFLP and DNA sequencing methods. A total of 14 synonymous polymorphisms were identified in the coding region. The analysis suggested that SNP1（G963A）, SNP7（C1632T）, SNP10（G1929A） and SNP11（G1947A） showed potential association with high-altitude environment because of their particular variation patterns in Tibetan pigs. Linkage disequilibrium（LD） of these SNPs was analyzed. One common LD block including 5 SNPs clustering in exon 12 was identified in all studied pig populations. Haplotype H1（AGGTC） in LD block was dominant in Tibetan pigs（76.6 and 74.2% in Linzhi（LZ） and Chayu（CY） pigs, respectively） and segregated at higher frequency than that in low-altitude pig breeds（52.3, 58.7 and 56.2% in Wuzhishan（WZS）, Min（M） and Laiwu（LW） pigs, respectively）, indicating that H1 may relate to adaptation to high altitude in Tibetan pigs. These findings raise hope that EPAS1 gene can be a candidate gene that involved in adaptation of high altitude in Tibetan pigs.

关键词： pig EPAS1 gene SNP haplotype nature selection

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