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基于LSDYNA的井下套管水力切割仿真与实验研究

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机械设计与制造 2024年第6期400卷 282-286,293页

作者：付文颜廷俊朱庆利王文胜北京化工大学机电工程学院北京100029 中石化胜利石油工程有限公司井下作业公司山东东营257000

为弥补传统井下开窗方法的不足,磨料水射流技术逐渐被应用到此领域,基于实际井下应用,若开出(30×50)mm的孔,则可继续喷射地层,实现一次性开窗及破岩。磨料水射流技术开窗具有效率高、无毛刺、喷嘴结构简单的特点。这里利用LSDYNA软件... 详细信息

为弥补传统井下开窗方法的不足,磨料水射流技术逐渐被应用到此领域,基于实际井下应用,若开出(30×50)mm的孔,则可继续喷射地层,实现一次性开窗及破岩。磨料水射流技术开窗具有效率高、无毛刺、喷嘴结构简单的特点。这里利用LSDYNA软件模拟磨料水射流对套管壁的冲蚀与仿真,并分析了割缝中工件压力分布。采用第一次实验确定模拟模型,利用第二次实验进行模型的验证,用确定好的模拟模型对不同结构的喷嘴进行仿真,为研制可切割(30×50)mm孔的喷嘴提供依据,节省实验成本。

关键词：磨料水射流 LSDYNA 流固耦合

Application and mechanism of Fenton-like iron-based functional materials for arsenite removal

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Transactions of Nonferrous Metals Society of China 2022年第12期32卷 4139-4155页

作者： qing-wei WANG Xue-lei YAN Mei-juan MA Ben-sheng li Zong-run li qing-zhu li School of Metallurgy and Environment Central South UniversityChangsha 410083China National Engineering Research Centre for Control and Treatment of Heavy Metal Pollution Central South UniversityChangsha 410083China Water Pollution Control Technology Key Lab of Hunan Province Changsha 410004China

Between the two major arsenic-containing salts in natural water, arsenite(As(Ⅲ)) is far more harmful to human and the environment than arsenate(As(V)) due to its high toxicity and transportability. Therefore, preoxidation of As(Ⅲ) to As(V) is considered to be an effective means to reduce the toxicity of arsenic and to promote the removal efficiency of arsenic. Due to their high catalytic activity and arsenic affinity, iron-based functional materials can quickly oxidize As(Ⅲ) to As(V) in heterogeneous Fenton-like systems, and then remove As(V) from water through adsorption and surface coprecipitation. In this review, the effects of different iron-based functional materials such as zero-valent iron and iron(hydroxy) oxides on arsenic removal are compared, and the catalytic oxidation mechanism of As(Ⅲ) in heterogeneous Fenton process is further clarified. Finally, the main challenges and opportunities faced by iron-based As(Ⅲ) oxidation functional materials are prospected.

关键词： Fenton-like reaction iron-based functional materials catalytic oxidation arsenic removal

Redox behavior and chemical species of arsenic in acidic aqueous system

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Transactions of Nonferrous Metals Society of China 2017年第9期27卷 2063-2072页

作者： Jin-qin YANG li-yuan CHAI qing-zhu li Yu-de SHU School of Metallurgy and Environment Central South University Changsha 410083 China National Engineering Research Centre for Control and Treatment of Heavy Metal Pollution Central South University Changsha 410083 China

Arsenic(As)removal from smelting acidic wastewater is an urgent *** most common method is oxidation of trivalent As(III)to pentavalent As(V)subsequently precipitated by ferric(Fe(III))*** of redox behavior and chemical species are of great importance for understanding As *** this work,cyclic voltammetry(CV)and UV?Vis spectroscopy were used for laboratory observation;meanwhile HSC and MINTEQ software were employed for theoretical *** is found that As(III)oxidation,a multiple electron transfer reaction,is *** oxidation over-potential is very high(about0.9V)in sulfuric acid solutions(pH1.0).In addition,Fe(III)?As(V)complexes are evidenced by UV?Vis spectra and chemical species analyses in series of Fe(III)?As(V)?H2SO4?H2O ***,the Fe(III)and As(V)species distribution against pH values are determined and a newφ?pH diagram with inclusion of Fe?As complexes is consequently compiled based on thermodynamic data predicted by other researchers.

关键词： arsenic ferric-arsenic complexes φ-pH diagram chemical species acidic wastewater

Role of contrast enhanced ultrasound in detection of abdominal aortic abnormalities in comparison with multislice computed tomography

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Chinese Medical Journal 2009年第7期122卷 858-864页

作者： Dirk-André Clevert Kerstin Schick CHEN Min-hua zhu qing-li Maximilian Reiser Department of Clinical Radiology Klinikum Grosshaderhl University of Munich - Grosshadern Campus Marchioninistr. 15 81377 Munich Germany Department of Surgery Klinikum Grosshaderhl University of Munich - Grosshadern Campus Marchioninistr. 15 81377 Munich Germany Department of Ultrasonography Beijing Cancer Hospital PekingUniversity School of Oncology Beijing Institute for CancerResearch Beijing 100036 China Department of Ultrasonography Peking Union Medical CollegeHospital Chinese Academy of Medical Sciences & Peking UnionMedical College Beijing 100730 China

Conventional ultrasound （US） is the most widely used imaging modality in routine clinical practice worldwide. The limitations of conventional ultrasound in the detection of aortic lesions versus multi-slice compute... 详细信息

关键词： contrast enhanced ultrasound multislice computed tomography abdominal aortic lesions aorticdissection abdominal aortic aneurysm aorto-caval fistula inflammatory abdominal aortic aneurysm

Multi-dimensional skin imaging evaluation of eccrine hidrocystoma

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Chinese Medical Journal 2020年第17期133卷 2107-2108页

作者： Yu-Kun Wang Yuan-Jing Gao Jie liu qing-li zhu Department of Dermatology Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Department of Ultrasound Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China

Eccrine hidrocystoma(EH)is a benign tumor derived from the cystic dilatation of the eccrine sweat ducts caused by the retention of eccrine *** is rare and is found most often in middle-aged women,especially those who work or stay for a long duration in hot and humid *** lesions usually involve periocular and malar areas,manifesting as multiple translucent skin-colored to bluish *** sizes and numbers of the lesions can fluctuate according to the season,with exacerbation in warm weather and alleviation in cold *** is histopathologically characterized by unilocular dermal cysts lined by two layers of cuboidal to flattened epithelial cells.

关键词： ocular weather sizes

Recovery of valuable metals from zinc leaching residue by sulfate roasting and water leaching

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Transactions of Nonferrous Metals Society of China 2017年第5期27卷 1180-1187页

作者： Guo-min JIANG Bing PENG Yan-jie liANG li-yuan CHAI qing-wei WANG qing-zhu li Ming HU School of Metallurgy and Environment Central South University Changsha 410083 China Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution Changsha 410083 China Changsha Science Environmental Technology Co. Ltd. Changsha 410000 China

Zinc leaching residue(ZLR),produced from traditional zinc hydrometallurgy process,is not only a hazardous waste but also a potential valuable *** combination of sulfate roasting and water leaching was employed to recover the valuable metals from *** ZLR was initially roasted with ferric sulfate at640°C for1h with ferric sulfate/zinc ferrite mole ratio *** this process,the valuable metals were efficiently transformed into water soluble sulfate,while iron remains as ferric ***,water leaching was conducted to extract the valuable metals sulfate for *** recovery rates of zinc,manganese,copper,cadmium and iron were92.4%,93.3%,99.3%,91.4%and1.1%,respectively.A leaching toxicity test for ZLR was performed after water *** results indicated that the final residue was effectively detoxified and all of the heavy metal leaching concentrations were under the allowable limit.

关键词： zinc leaching residue sulfate roasting water leaching valuable metals recovery

Study on Properties of Ti(C,N)/TiN Multi-Element-layer Films Plus Nanometer Lubrication Dry Films

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材料热处理学报 2004年第5B期25卷 909-912页

作者： HUANGYuan-lin MAShi-ning liChang-qing zhuYou-li StateKeyLaboratoryforRemanufacturing Beijing100072China

Ti(C,N)/TiN multi-element-layer films was deposited on aluminium alloy substrates by using multi-arc ion plating. The microhardness of the films was 2000HV0.i which was nearly 21 times of that of the substrates. XRD analysis show that the main composition of the composite films system were Ti(C,N), TiN, Al3Ti, Al and a little Ti2N. The presence of MjTi new phase in the interface of the films/substrates indicated some metallurgical bonding between them, which implies higher adhesive strength of the films/substrates system. Pin-on-disc tests showed that the wear resistance of the substrates was improved substantially. However, the coefficient of friction of the films/substrate system was high (u=0.66), which resulted in the wear of the counterparts. To reduce the coefficient of friction, nanometer lubrication dry films was applied on top of the multi-element-layer films to form composite films system and subsequent wear tests showed that the resulting composite films led to reduction of the coefficient of friction from 0.66 to 0.16. Meanwhile, wear mass loss of the counterpart was reduced from 1.29 mg to 0.02 mg, so that increased wear resistance and reduced friction effects were achieved.

关键词：多电弧离子电镀法铝合金摩擦学纳米薄膜

THE SCHEME FOR THE DATABASE BUILDING AND UPDATING OF 1∶10 000 DIGITAL ELEVATION MODELS

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Geo-Spatial Information Science 2000年第2期3卷 19-25页

作者： zhu qing li Zhilin GONG Jianya SUI Haigang National Laboratory for Information Engineering in Surveying Mapoing and Remote Sensing WTUSM Wuhan China

The National Bureau of Surveying and Mapping of China has planned to speed up the development of spatial data infrastructure (SDI) in the coming few *** SDI consists of four types of digital products,i.e.,digital orthophotos,digital elevation models, digital line graphs and digital raster *** the DEM,a scheme for the database building and updating of 1∶10 000 digital elevation models has been proposed and some experimental tests have also been *** paper describes the theoretical (and/or technical) background and reports some of the experimental results to support the *** aspects of the scheme such as accuracy,data sources,data sampling,spatial resolution,terrain modeling,data organization,etc are discussed.

关键词： geospatial data DEM photogrammetric sampling cartographic digitization specification

A new mixed-valent iron arsenate black crystal

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Transactions of Nonferrous Metals Society of China 2018年第5期28卷 1036-1044页

作者： Jin-qin YANG qing-zhu li li-yuan CHAI qing-wei WANG Hui liU Xiao-bo MIN Rui-yang XIAO School of Metallurgy and Environment Central South University Changsha 410083 China National Engineering Research Centre for Control and Treatment of Heavy Metal Pollution Central South University Changsha 410083 China

Scorodite（FeAsO4·2H2O）is the most popular phase for arsenic（As）immobilization while the reductive dissolution of Fe（Ⅲ）to Fe（Ⅱ）will promote As *** the present study,an equilibrium between Fe（Ⅲ）and Fe（Ⅱ）was achieved in scorodite preparation system by introducing certain alcohol（methanol,ethanol,isopropanol or tert-butanol）,and thus a new mixed-valent iron arsenate black crystal formulated as Fe（Ⅱ）（5.2）Fe（Ⅲ）（8.8）（HAsO4）4（AsO4）8·H2O was *** comparison with scorodite,the black crystal has higher As content（36.4%,mass fraction）and lower crystal water content（0.73%,mass fraction）.Additionally,the leaching concentration of As can be lower than the threshold value（5 mg/L）regulated by identification standards for hazardous wastes of China（GB 5080.3-2007）.Therefore,this new mixed-valent iron arsenate crystal could be classified as a non-hazardous and promising As-bearing phase in environmental applications.

关键词： arsenic iron crystal arsenic immobilization hazardous wastes