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SOME SPECIAL SELF-SIMILAR SOLUTIONS FOR A MODEL OF INVISCID LIQUID-GAS TWO-PHASE FLOW

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Acta Mathematica Scientia 2021年第1期41卷 114-126页

作者： jianwei dong Manwai YUEN School of Mathematics Zhengzhou University of AeronauticsZhengzhou 450015China Department of Mathematics and Information Technology The Education University of Hong Kong10 Lo Ping RoadTai PoNew TerritoriesHong KongChina

In this article,we are concerned with analytical solutions for a model of inviscid liquid-gas two-phase *** the basis of Yuen’s works[25,27–29]on self-similar solutions for compressible Euler equations,we present some special self-similar solutions for a model of inviscid liquid-gas two-phase flow in radial symmetry with and without rotation,and in elliptic symmetry without *** blowup phenomena and the global existence of the solutions obtained are classified.

关键词： two-phase flow analytical solutions self-similar blowup global solutions

Application of Hydrocracking Process for Upgrading Tail Oil Quality in 1.0 Mt/a Hydrocracker Unit at SINOPEC Yangzi Petrochemical Company

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China Petroleum Processing & Petrochemical Technology 2009年第1期11卷 13-17页

作者： Zhang Haichun dong jianwei SINOPEC Yangzi Petrochemical Company Nanjing 210048 SINOPEC Research Institute of Petroleum Processing

This article focuses on the hydrocracking technology for upgrading the quality of tail oil and the first commercial application of the RN-32V/RHC- 1 catalysts in the 1.0 Mt/a hydrocracker at the Yangzi Petrochemical Company, which was started up successfully in September 2008. One month after start-up of the hydrocracking unit, an evaluation opera- tion has been conducted fbr assessing the catalysts performance. The technical calibration results showed that the RN- 32V/RHC-1 catalysts had high activity, and the product yield distribution was reasonable. The hydrocracker can provide abundant feedstocks for the downstream aromatic production unit and ethylene production unit.

关键词： hydrocracking upgrading tail oil quality catalysts application

Multisource Target Classification Based on Underwater Channel Cepstral Features

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Journal of Ocean University of China 2022年第4期21卷 917-925页

作者： LI Xiukun JIA Hongjian dong jianwei QIN Jixing College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China Acoustic Science and Technology Laboratory Harbin Engineering UniversityHarbin 150001China Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001China State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China

Passive target detection through shipping-radiated noise is a key technology in current underwater operations and is of great research value in civil and military *** this study,the stable spectral line component of shipping-radiated noise is used as the research object,and the classification of multisource targets is studied from the perspective of underwater *** utilize the channel impulse response function as the classification basis of different ***,the underwater channel is estimated by the ***,the channel cepstral features carried by different spectral line components are extracted in ***,the spectral line components belonging to the same target are clustered by the cepstral feature distance to realize the classification of different *** simulation and experimental results verify the effectiveness of the proposed method in this research.

关键词： shipping-radiated noise underwater channel cepstral features target classification

Variations in concentrations and bioavailability of heavy metals in rivers caused by water conservancy projects： Insights from water regulation of the Xiaolangdi Reservoir in the Yellow River

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Journal of Environmental Sciences 2018年第12期30卷 79-87页

作者： jianwei dong Xinghui Xia Zhining Zhang Zixuan Liu Xiaotian Zhang Husheng Li State Key Laboratory of Water Environment Simulation Key Laboratory for Water and Sediment Sciences of Ministry of EducationSchool of Environment Beijing Normal University Beijing 100875 China Center for Eco-Environmental Research Nanjing Hydraulic Research Institute Nanjing 210029 China Beijing Center for Physical & Chemical Analysis Beijing 100089 China Hubei Provincial Center for Disease Control and Prevention Wuhan 430079 China

Water regulation of the Xiaolangdi Reservoir of the Yellow River was chosen as a case to investigate variations in concentrations and bioavailability of heavy metals caused by water conservancy projects in rivers. Water and suspended sediment（SPS） samples were collected at downstream sampling sites along the river during this period. Concentrations and speciation of Zn, Cr, Cu, Ni, and Pb in water and SPS samples were analyzed, and their bioaccumulation was studied with Daphnia magna. This study indicated that the exchangeable and carbonatebound fractions of heavy metals in SPS decreased along the studied stretch, and the dissolved heavy metal concentrations increased along the river with 1.6–15 folds. This is because sediment resuspension increased along the river during water regulation, giving rise to the increase of heavy metal release from SPS. The dissolved Zn, Cu, Ni, and Pb concentrations were significantly positively correlated with SPS concentrations, and their increase along the river was greater than Cr. The body burdens of heavy metals in D. magna exposed into samples collected from the reservoir outlet were 1.3–3.0 times lower than those from downstream stations, suggesting that the heavy metal bioavailability increased during water *** should be considered in the reservoir operation.

关键词： Heavy metals Speciation Bioaccumulation Suspended sediment Dam Water conservancy project

Antibiotics along an alpine river and in the receiving lake with a catchment dominated by grazing husbandry

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Journal of Environmental Sciences 2022年第5期34卷 374-382页

作者： jianwei dong Dandan Yan Kangle Mo Qiuwen Chen Jianyun Zhang Yuchen Chen Zhiyuan Wang State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210029China Center for Eco-Environmental Research Nanjing Hydraulic Research InstituteNanjing 210029China Yangtze Institute for Conservation and Green Development Nanjing 210029China School of Marine Science and Engineering Nanjing Normal UniversityNanjing 210023China

The livestock breeding industries face overuse of antibiotics,which has been intensively studied in recent ***,the occurrence and fate of antibiotics as well as their potential threats to the aquatic environments in alpine and arid regions remain *** study investigated the relationship of the occurrence and concentrations of antibi-otics between the Kaidu River and Bosten Lake in a typical alpine basin in *** spots with antibiotic pollution source were *** antibiotic concentrations in river water and suspended sediment(SPS)were 2.20-99.4 ng/L and 1.03-176 ng/*** dominant antibi-otics were tetracyclines,sulphacetamide,and ofloxacin in river water and sulfonamides,clarithromycin,roxithromycin,and ofloxacin in *** apparent differences in pollution sources and landscapes in different reaches led to the obvious spatial patterns of antibiotics in the Kaidu *** partition coefficient of antibiotic between SPS and water phases for sulfonamides than tetracyclines was because that tetracyclines strongly responded to clay contents while sulfonamides significantly responded to organic carbon contents in *** were significant differences in detected antibiotic categories between the river and the ***(especially ciprofloxacin and enrofloxacin)were detected in the lake while sulphacetamide was only detected in the ***,the surrounding husbandry and aquaculture around the Bosten Lake was an important antibiotic pollution source in addition to inputs from the Kaidu *** research suggested that alpine lakes could be an important sink of antibiotics in alpine dry regions,and thus impose greater threats to the aquatic ecosystem.

关键词： Antibiotics Lotic-lentic contamination Suspended sediment Partition

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高铁开通与风险资本投资的企业创新

现代经济探讨 2019年第8期 94-104页

作者：董建卫西北大学经济管理学院

基于风险资本监督视角,研究高铁开通对风险资本投资的企业创新的影响。以私募通数据库接受A轮风险资本投资的企业为样本,使用负二项分布模型,研究表明:高铁开通对风险资本投资的企业创新有显著正向影响。风险资本与所投企业的地理距离远... 详细信息

基于风险资本监督视角,研究高铁开通对风险资本投资的企业创新的影响。以私募通数据库接受A轮风险资本投资的企业为样本,使用负二项分布模型,研究表明:高铁开通对风险资本投资的企业创新有显著正向影响。风险资本与所投企业的地理距离远,风险资本属于非国有背景,所投企业处于发展早期时,上述效应更加明显。替换企业创新测量指标,以接受B轮风险资本投资的企业为样本,剔除选择效应后,上述效应依然存在。可见,风险资本投资的企业所处城市开通高铁后,由于交通时间成本下降,风险资本会加强对企业监督,从而促进企业创新。

关键词：高铁风险资本企业创新交通

一维稳态量子Navier-Stokes方程组古典解的唯一性(英文)

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应用数学 2013年第2期26卷 446-450页

作者：董建伟郑州航空工业管理学院河南郑州450015

文[9]得到了一维稳态量子Navier-Stokes方程组古典解的存在性,本文在某些条件下利用一些不等式技巧继续证明了其解的唯一性.

关键词：量子Navier—Stokes方程组稳态解唯一性

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基于小波变换的脉搏波标志点检测方法

数据采集与处理 2006年第B12期21卷 40-43页

作者：张石杜恺董建威东北大学信息科学与工程学院沈阳110004

针对脉搏波信号的标志点检测提出了一种基于小波变换的信号特征检测方法。该方法首先对脉搏波信号在小尺度上进行小波变换,然后利用系数中的极大极小值对来确定原始信号峰值的范围,进而返回原始信号定位峰值点。最后以原始信号的峰值为... 详细信息

针对脉搏波信号的标志点检测提出了一种基于小波变换的信号特征检测方法。该方法首先对脉搏波信号在小尺度上进行小波变换,然后利用系数中的极大极小值对来确定原始信号峰值的范围,进而返回原始信号定位峰值点。最后以原始信号的峰值为参照点提取出其他标志点的具体位置。采用此方法进行脉搏波信号的标志点定位,为进一步进行血流动力学参数的计算研究奠定了基础。

关键词：脉搏波小波变换标志点

初沉—混凝沉淀—吸附工艺处理高浓度含氟废水工程实例

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工业水处理 2014年第8期34卷 82-84页

作者：董建威四川理工学院建筑工程学院四川自贡643000

针对某石英制品企业排放的高浓度含氟废水,采用初沉-混凝沉淀-吸附组合工艺进行处理。工程实践结果表明:在加药量维持相对稳定的情况下,出水氟化物质量浓度可稳定控制在5 mg/L以下,达到了当地环境保护局要求的控制标准。

关键词：含氟废水混凝沉淀吸附