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High surface area, high catalytic activity titanium dioxide aerogels prepared by solvothermal crystallization

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Journal of Materials Science & Technology 2020年第12期47卷 223-230页

作者： Xian Yue Junhui Xiang junyong chen Huaxin Li Yunsheng Qiu Xianbo Yu Center of Materials Science and Optoelectronics Engineering College of Materials SciencesUniversity of Chinese Academy of SciencesBeijing 100049China

Titanium dioxide has been considered to be one of the most effective and environmental friendly photocatalytic *** has been widely used in photocatalytic degradation of various *** we known,an anatase crystal form typically obtained by high temperature heat treatment(>600℃),usually shows higher catalytic *** order to further improve the catalytic efficiency,we prepared TiO2 with a non-supercritical drying method to form a high specific surface area aerogel structure,along with an increased active contact ***,with the inevitable of internal pores collapse in the process of high temperature crystallization,a large amount of porous structure and specific surface area is ***,to enhance the photocatalytic activity of titania,we propose a synergistic strategy to fabricate a porous titania structure with a high specific surface *** was crystallized at a lower temperature(120℃) in a low-boiling solvent(ethanol,acetone,etc.).The lattice structure was identified by X-ray diffractometry;specific surface area(over 300 m2/g) of our sample was also measured through BET test;in the subsequent photocatalytic degradation test,the photocatalytic degradation efficiency of fabricated TiO2 is proved to be more excellent than P25 *** a freeze-drying/mild crystallization method,a high-specific surface area and high catalytic activity TiO2 aerogel was *** study provides some insights in the combining of crystallization and high specific surface area of titanium dioxide photocatalysis.

关键词： TiO2 aerogel Non-supercritical drying Low temperature crystallization Photocatalysis

Metabolic engineering of Bacillus amyloliquefaciens for efficient production ofα-glucosidase inhibitor1-deoxynojirimycin

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Synthetic and Systems Biotechnology 2023年第3期8卷 378-385页

作者： Xujie Li Meng Zhang Yu Lu Ningyang Wu Jian’gang chen Zhixia Ji Yangyang Zhan Xin Ma junyong chen Dongbo Cai Shouwen chen State Key Laboratory of Biocatalysis and Enzyme Engineering Environmental Microbial Technology Center of Hubei ProvinceCollege of Life SciencesHubei UniversityWuhan430062China State Key Laboratory of Agricultural Microbiology Huazhong Agricultural UniversityWuhan430070China Department of Urology Zhuhai People’s Hospital(Zhuhai Hospital Affiliated to Jinan University)Zhuhai519000China Wuhan Jun’an Biotechnology Co. Ltd.Wuhan430070China

Owing to the feature of strongα-glucosidase inhibitory activity,1-deoxynojirimycin(1-DNJ)has broad application prospects in areas of functional food,biomedicine,etc.,and this research wants to construct an efficient strain for 1-DNJ production,basing on Bacillus amyloliquefaciens ***,using the temperature-sensitive shuttle plasmid T2(2)-Ori,gene ptsG in phosphotransferase system(PTS)was weakened by homologous recombination,and non-PTS pathway was strengthened by deleting its repressor gene iolR,and 1-DNJ yield of resultant strain HZ-S2 was increased by 4.27-fold,reached 110.72 mg/***,to increase precursor fructose-6-phosphate(F-6-P)supply,phosphofructokinase was weaken,fructose phosphatase GlpX and 6-phosphate glucose isomerase Pgi were strengthened by promoter replacement,moreover,regulator gene nanR was deleted,1-DNJ yield was further increased to 267.37 mg/L by ***,promoter of 1-DNJ synthetase cluster was optimized,as well as 5′-UTRs of downstream genes in synthetase cluster,and 1-DNJ produced by the final strain reached 478.62 mg/*** but not the least,1-DNJ yield of 1632.50 mg/L was attained in 3 L fermenter,which was the highest yield of 1-DNJ reported to *** together,our results demonstrated that metabolic engineering was an effective strategy for 1-DNJ synthesis,this research laid a foundation for industrialization of functional food and drugs based on 1-DNJ.

关键词： 1-Deoxynojirimycin Bacillus amyloliquefaciens Metabolic engineering Glucose transport pathway Fructose 6-phosphate 1-DNJ synthetase Gene cluster

Geodetic Height Determination in 2005 Qomolangma Survey

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Geo-Spatial Information Science 2007年第2期10卷 79-84页

作者： DANG Yamin chenG Chuanlu chen junyong ZHANG Peng Chinese Academy of Surveying and Mapping 16 Beitaiping Road Beijing 100039 China

Determining the geodetic height of Mount Qomolangma was one of the very important missions in the 2005 Qomolangma height survey. There were three GPS networks in the survey: regional GPS crustal deformation network, geodetic GPS control network, and GPS measurement on the mountain summit. Data collection and processing were introduced. The final data processing strategy and reasonable geodetic height were fairly determined based on careful data analysis.

关键词： Qomolangma geodetic height GPS measurement

对SRTM3和GTOPO30地形数据质量的评估

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武汉大学学报（信息科学版） 2005年第11期30卷 941-944页

作者：陈俊勇国家测绘局办公室北京市百万庄100830

高分辨率的地形数据在基础地理信息系统、地球重力场建模和大地水准面求定等工程中至关重要。SRTM有3″×3″(SRTM3)和1″×1″(SRTM1)两种分辨率。就全球而言,SRTM3的原始数据已于2004年解密。SRTM3的高程基准是EGM96的大地水准面,平... 详细信息

高分辨率的地形数据在基础地理信息系统、地球重力场建模和大地水准面求定等工程中至关重要。SRTM有3″×3″(SRTM3)和1″×1″(SRTM1)两种分辨率。就全球而言,SRTM3的原始数据已于2004年解密。SRTM3的高程基准是EGM96的大地水准面,平面基准是WGS84;标称绝对高程精度是±16m,绝对平面精度是±20m。SRTM3的数据只覆盖60°N至54°S带状区域内的DSM。对覆盖全球的GTOPO30的DTM也作了概要介绍。

关键词：地形数据 DTM DSM SRTM GTOPO30 质量评估

国际地球参考框架2000(ITRF2000)的定义及其参数

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武汉大学学报（信息科学版） 2005年第9期30卷 753-756,761页

作者：陈俊勇国家测绘局办公室北京市百万庄100830

对国际地球参考框架2000(ITRF2000)的定义、主要参数及其应满足的条件进行了研究,重点指出了它和历史上的各个ITRFyy的不同,并阐述了各个ITRFyy的联系和区别,给出了它们之间相互转换的参数。

关键词：国际地球参考系统2000(ITRS2000) 国际地球参考框架2000(ITRF2000) 参数

Square ZnO nano-column and its thermal evolution

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Science China(Technological Sciences) 2010年第2期53卷 309-312页

作者： HUANG BinWang, ZHAN HuaHan, WU YaPing, chen XiaoHang & KANG junyong Key Laboratory of Semiconductor Materials and Applications, Department of Physics, Xiamen University, Xiamen 361005, China 1. Key Laboratory of Semiconductor Materials and Applications Department of Physics Xiamen University Xiamen 361005 China

Square ZnO nano-columns have been manufactured by molecular beam epitaxy on p-type Si (100) substrate. The morphology and the evolution sequences after thermal annealing were investigated by in-situ scanning tunneling microscopy. We associated the morphology and microstructure evolution with the cubic Si (100) substrate, large lattice mismatching, the coexistence of wurtzite and zincblende phases of ZnO, and the thermal effect.

关键词： ZnO square nano-column anneal wurtzite phase zincblende phase Si (100)

Experiments on Development of Channel Pattern in the Process of River Reformation

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四川大学学报（工程科学版） 2005年第S1期37卷 128-132页

作者： ZHANG junyong chen Li LIU Yucheng DING Zhiliang(State Key Lab.of Water Resources and Hydropower Eng.Sci.,Wuhan Univ.,Wuhan 430072,China) Lab. of Water Resources and Hydropower Eng. Sci. Wuhan Univ. Wuhan 430072 China

The changing of flow conditions caused by construction of hydro-projects will result in river's refor- mation and development of channel *** this paper,the development of channel pattern in the process of reformation is studied by means of flume *** of slope,grain size,angle-of-inflow,dis- charge and discharge process are comprehensively analyzed according to the experimental *** was found that the channel would be widened as the river slope or discharge increased and grain s...

关键词： reformation process channel pattern angle-of-inflow discharge process

基于动态Lloyd-Max量化的网络化系统实时状态估计

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传感技术学报 2023年第11期36卷 1754-1760页

作者：陈军勇浙江科技学院信息与电子工程学院浙江杭州310023

针对网络化线性动态系统的实时状态估计,采用均方误差(MSE)作为性能准则,研究了最优实时量化与估计结构和具体实现方案。根据估计-量化分离原理,优化问题可以等效转换为一阶高斯-马尔可夫信源的最优量化与重构问题,分析了最优实时量化... 详细信息

针对网络化线性动态系统的实时状态估计,采用均方误差(MSE)作为性能准则,研究了最优实时量化与估计结构和具体实现方案。根据估计-量化分离原理,优化问题可以等效转换为一阶高斯-马尔可夫信源的最优量化与重构问题,分析了最优实时量化与估计的等效结构形式。基于向量Lloyd-Max量化原理和量化信源预测分布的高斯近似,设计了递推形式的动态Lloyd-Max量化与估计(DLMQE)实现方案,其中采用双边同步器利用发送端和接收端的共有信息实现编码与解码操作的同步,并导出了最优实时估计和误差协方差阵的解析形式。仿真结果表明,所提出的DLMQE方案估计性能优于现有的量化卡尔曼滤波器(QKF),且即使对于较低量化比特率的区域,DLMQE算法依然有效。

关键词：状态估计均方误差 Lloyd-Max量化双边同步器

CHINA: MAIN GEODETIC ACTIONS 1996-2000

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Bulletin of the Chinese Academy of Sciences 1996年第4期10卷 286-290页

作者： chen junyong(National Bureau of Surveying and Mapping, Beijing) CAS Member

This article reviews the progress made in geodetic work in China since the *** order to meet the needs of China’s economic and defense construction,and scientific and social development in the early 21th century,some main geodetic actions which should be completed before 2000 are proposed as follows.(1) Monitoring vertical crustal movements and conducting studies on its *** of the second phase of the national first order leveling *** of the vertical crustal movement.(2) Improvement of national space geodetic *** main task is to lay down a national B-order GPS network and complete its data processing.(3) Refining of Chinese local gravity field on land and *** determination of Chinese local quasi geoid with higher than one meter *** of

关键词： GPS data VLBI MAIN GEODETIC ACTIONS 1996-2000 CHINA