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钻屑回注泵液力端有限元分析

广州化工 2024年第4期52卷 145-148页

作者：郭玉树石成辉李斌张贵磊中海油田服务股份有限公司河北廊坊065201

岩屑回注技术是有效处理钻井废弃物以及消除其对环境影响的重要手段。但由于岩屑回注浆体中含有大量微小颗粒,在回注过程中对于回注泵液力端的磨损较大,导致岩屑回注泵寿命较短。为此,通过ANSYS数值模拟软件的FLOTRAN CFD模块分析液力... 详细信息

岩屑回注技术是有效处理钻井废弃物以及消除其对环境影响的重要手段。但由于岩屑回注浆体中含有大量微小颗粒,在回注过程中对于回注泵液力端的磨损较大,导致岩屑回注泵寿命较短。为此,通过ANSYS数值模拟软件的FLOTRAN CFD模块分析液力端内的流场分布,分析发现:吸入工况下,流体流经吸入凡尔时流道过流面积最小,所形成的流速最高;排出工况下,流体在排出凡尔左侧壁面形成最大流速,且在出口附近产生漩涡。液力端基体材料采用沉淀硬化性不锈钢合金,延长了液力端凡尔周围材料的耐磨性,延长回注泵使用寿命。

关键词：钻屑回注液力端磨损数值模拟液力端流场液力端耐磨性

Discrete element modelling of railway ballast performance considering particle shape and rolling resistance

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Railway Engineering Science 2020年第4期28卷 382-407页

作者： Yunlong guo Chunfa Zhao Valeri Markine Can shi guoqing Jing Wanming Zhai Faculty of Civil Engineering and Geosciences Delft University of Technology2628CN DelftThe Netherlands Train and Track Research Institute State Key Laboratory of Traction PowerSouthwest Jiaotong UniversityChengdu 610031China School of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China

To simulate ballast performance accurately and efficiently,the input in discrete element models should be carefully selected,including the contact model and applied particle *** study the effects of the contact model and applied particle shape on the ballast performance(shear strength and deformation),the direct shear test(DST)model and the large-scale process simulation test(LPST)model were developed on the basis of two types of contact models,namely the rolling resistance linear(RRL)model and the linear contact(LC)*** shapes are differentiated by clumps.A clump is a sphere assembly for one ballast *** results show that compared with the typical LC model,the RRL method is more efficient and realistic to predict shear strength results of ballast assemblies in *** addition,the RRL contact model can also provide accurate vertical and lateral ballast deformation under the cyclic loading in LPSTs.

关键词： Discrete element method Ballast performance Boundary condition Rolling resistance Direct shear test Lateral displacement

Intravascular treatment for abnormal catheter positioning of port-a-cath system in the subclavian vein:A single-center study

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Journal of Interventional Medicine 2022年第2期5卷 103-110页

作者： Yong Li jianxi guo Yanfang Zhang jian Kong Department of Interventional Radiology Shenzhen People’s Hospital (Second Clinical Medical College of Jinan University First Affiliated Hospital of Southern University of Science and Technology)ShenzhenChina

Objective:This study aimed to explore the incidence of abnormal catheter positioning and the effectiveness and safety of intravascular adjustment or removal of abnormally positioned catheters through percutaneous *** and methods:A retrospective analysis was conducted on 58 patients with abnormal catheter positioning,treated between January 2009 and June *** adjustment of the migrated catheters and removal of the fractured catheters were performed through percutaneous puncture using a pigtail catheter,cobra catheter,and gooseneck ***:Of the 58 cases,there were 23 cases of catheter migration and 35 cases of catheter *** incidence of abnormal catheter positioning was 3.0%,corresponding to 1.2%migrations and 1.8%*** the 23cases of migration,1 case did not require adjustment and another underwent unsuccessful *** rate of successful adjustment of migrated catheters was 91.3%,whereas the rate of successful removal of fractured catheters was 100%.No surgery-related complications were observed either immediately or during the 1-month follow-up ***:This study showed that the incidence of abnormal catheter positioning is *** techniques used for the adjustment or removal of abnormally placed catheters are safe,efficient,and minimally invasive.

关键词： Port-a-cath system Tip migration Catheter fracture Intravascular treatment

Comparison Study on Characteristic Regimes in Shocked Porous Materials

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Chinese Physics Letters 2010年第2期27卷 209-212页

作者：许爱国张广财李华朱建士 National Key Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsPO Box 8009-26Beijing 100088

We perform a comparison study on characteristic regimes in shocked porous materials whose mechanical properties cover a wide range. Via the Minkowski functional analysis, it is found that different materials may show the same fractional size of characteristic regimes in the shock-loading procedure, even if one uses the same threshold value to define those regimes. Characteristic regimes in the material with larger initial yield are more dispersed. For a fixed shock strength, there exists a material strength with which the shock wave reaction contributes the maximum plastic work. With the decreasing of shock strength, this material strength becomes smaller. These observations may present helpful indications for new material designs.

关键词： Condensed matter: structural mechanical & thermal

微塑料及其复合污染对农作物生长影响的研究进展

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河南师范大学学报（自然科学版） 2024年第5期52卷 10-18页

作者：郭笑盈王琼豆贝贝李心棋王甜甜师勇强王岩郑州大学生态与环境学院郑州450001 郑州大学河南省环境与资源国际联合实验室郑州450001 中国农业科学院棉花研究所河南安阳455000

微塑料作为一类新污染物,已被大量研究证实广泛存在于土壤环境中,并对农作物生长及生理性状产生了不良影响,进而威胁粮食安全、危害人类健康.微塑料对农作物生长发育的影响主要包括对农作物种子发芽、幼苗生长和生理指标的毒性效应以及... 详细信息

微塑料作为一类新污染物,已被大量研究证实广泛存在于土壤环境中,并对农作物生长及生理性状产生了不良影响,进而威胁粮食安全、危害人类健康.微塑料对农作物生长发育的影响主要包括对农作物种子发芽、幼苗生长和生理指标的毒性效应以及对抗氧化系统的刺激作用.系统总结并梳理了微塑料及其复合污染对农作物生长发育的影响,归纳了微塑料不同性质对农作物产生的毒性效应机制,以期能为农田土壤微塑料污染的生态风险评估及治理防控提供理论依据与科学支撑.

关键词：微塑料农作物生长发育复合污染

异基因造血干细胞移植治疗Shwachman-Diamond综合征:3例报告及文献复习

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中华血液学杂志 2024年第7期45卷 689-693页

作者：冯安华施继敏傅华睿余建郑伟燕朱园园黄河赵妍敏浙江大学医学院附属第一医院骨髓移植中心杭州310003 山东第二医科大学附属医院血液病科潍坊261035

研究报告了在浙江大学医学院附属第一医院接受异基因造血干细胞移植(allo-HSCT)的3例Shwachman-Diamond综合征(SDS)患者,并结合相关文献资料总结SDS的临床表现和基因突变特征,探讨allo-HSCT对此类患者的疗效及移植时机。3例SDS患者均为... 详细信息

研究报告了在浙江大学医学院附属第一医院接受异基因造血干细胞移植(allo-HSCT)的3例Shwachman-Diamond综合征(SDS)患者,并结合相关文献资料总结SDS的临床表现和基因突变特征,探讨allo-HSCT对此类患者的疗效及移植时机。3例SDS患者均为男性,移植年龄分别为32、33、32岁。3例患者均为幼年发病,例1以贫血为首发临床表现,后逐渐进展为全血细胞减少;例2、3均以全血细胞减少为首发临床表现。例1、3有智力障碍,例3有胰腺脂肪化及慢性胰腺炎表现。3例患者均身材矮小。3例患者均检出SBDS:c.258+2T>C剪切位点杂合突变。3例患者的家系成员均无SDS临床表现。3例患者均采用减低剂量预处理方案(氟达拉滨+白消安+司莫司汀+兔抗人胸腺细胞免疫球蛋白)。例1、例2行单倍体造血干细胞移植,例3行无关供者造血干细胞移植。例1移植前诊断骨髓增生异常综合征转化急性髓系白血病,移植后早期复发并死亡;例2为继发性植入不良,血小板输注依赖;例3移植后脱离药物维持治疗,血常规正常。

关键词：全血细胞减少骨髓增生异常综合征急性髓系白血病慢性胰腺炎药物维持治疗身材矮小血小板输注造血干细胞移植

Nanocellulose from various biomass wastes:Its preparation and potential usages towards the high value-added products

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Environmental Science and Ecotechnology 2021年第1期5卷 10-21页

作者： Sujie Yu jianzhong Sun Yifei shi Qianqian Wang jian Wu Jun Liu Biofuels Institute School of the Environment and Safety EngineeringJiangsu University301 Xuefu Road212013ZhenjiangChina Key Laboratory of Pulp and Paper Science&Technology of Ministry of Education Qilu University of Technology(Shandong Academy of Sciences)250353JinanChina

Biomass waste comes from a wide range of sources,such as forest,agricultural,algae wastes,as well as other relevant industrial *** is an important alternative energy source as well as a unique source for various bioproducts applied in many *** the past two decades,how to reuse,recycle and best recover various biomass wastes for high value-added bioproducts has received significant attention,which has not only come from various academia communities but also from many civil and medical *** summarize one of the cutting-edge technologies applied with nanocellulose biomaterials,this review focused on various preparation methods and strategies to make nanocellulose from diverse biomass wastes and their potential applications in biomedical areas and other promising new fields.

关键词： Biomass waste Nanocellulose Biomedical application Environmentally-functional materials

南昌地铁地下多管线近邻地铁人行通道的施工影响分区

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科学技术与工程 2024年第11期24卷 4679-4688页

作者：吴波郑卫强郭方雨徐世祥万友生覃君朱文华东华理工大学土木与建筑工程学院南昌330013 广西大学土木建筑工程学院南宁530004 南昌轨道交通集团有限公司地铁项目管理分公司南昌330038 中铁二局第六工程有限公司成都610083

针对地下地铁人行通道暗挖施工对近邻多管线扰动影响问题,依托南昌地铁3号线邓埠站1号出入口人行通道暗挖工程,采用数值计算与理论分析相结合的方法,系统研究了通道暗挖施工扰动作用下近邻多管线的力学特性,总结关键因素对管线力学行为... 详细信息

针对地下地铁人行通道暗挖施工对近邻多管线扰动影响问题,依托南昌地铁3号线邓埠站1号出入口人行通道暗挖工程,采用数值计算与理论分析相结合的方法,系统研究了通道暗挖施工扰动作用下近邻多管线的力学特性,总结关键因素对管线力学行为的影响规律,提出了通道暗挖下近邻密集管线影响分区计算方法与控制措施。结果表明:结合Peck曲线分布规律确定出以控制值的60%与20%作为强影响分区、弱影响分区、无影响分区的阈值;采用多元非线性函数进行拟合得出的线竖向位移与多因素的关系函数,对影响分区划分效果较好;建立的地铁隧道暗挖对近邻密集管线强弱影响分区方法,可通过有效的措施将密集管线强影响区转变为弱影响区和无影响区,进而保障施工安全。

关键词：通道暗挖多管线数值模拟影响区控制措施

低温等离子体处理对玉米醇溶蛋白-百里香酚微胶囊功能特性的影响研究

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粮食与油脂 2024年第8期37卷 85-89,111页

作者：王亚潇李晓宇王建航韩思琦郭鹏董爽山东理工大学农业工程与食品科学学院山东淄博255000 山东扳倒井股份有限公司山东淄博256399

采用低温等离子体技术辅助制备玉米醇溶蛋白-百里香酚微胶囊(ZTM),研究低温等离子体处理功率对ZTM的抗氧化活性、加工与储存稳定性和体外缓释特性的影响。结果表明:与未处理的ZTM相比,经45~80 W低温等离子体处理的ZTM,其抗氧化活性有所... 详细信息

采用低温等离子体技术辅助制备玉米醇溶蛋白-百里香酚微胶囊(ZTM),研究低温等离子体处理功率对ZTM的抗氧化活性、加工与储存稳定性和体外缓释特性的影响。结果表明:与未处理的ZTM相比,经45~80 W低温等离子体处理的ZTM,其抗氧化活性有所提高。低温等离子体处理对ZTM的加工和贮藏稳定性起着积极作用,其中经50 W低温等离子体处理的ZTM稳定性最好。体外缓释试验显示,在模拟胃液中,经低温等离子体处理的ZTM中百里香酚的释放率比未处理的ZTM低;而在模拟肠液中,经低温等离子体处理的ZTM中百里香酚的释放率相比未处理的ZTM有所增加。

关键词：低温等离子体玉米醇溶蛋白百里香酚微胶囊稳定性