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兴保铁路冯家川站新建装车环线方案研究

铁道货运 2024年第6期42卷 6-12页

作者：马孟祺刘俊奚文媛刘志军中铁工程设计咨询集团有限公司线路站场设计研究院北京100055

兴保铁路是国家“西煤东输”能源动脉瓦日铁路集疏运系统的重要组成部分,冯家川站作为兴保铁路的起点装车站,既有双线装车环线不能满足车站装车需求的状况愈发凸显,故在兴保铁路增设二线的同时,冯家川站亟需新建装车线满足新增货运量的... 详细信息

兴保铁路是国家“西煤东输”能源动脉瓦日铁路集疏运系统的重要组成部分,冯家川站作为兴保铁路的起点装车站,既有双线装车环线不能满足车站装车需求的状况愈发凸显,故在兴保铁路增设二线的同时,冯家川站亟需新建装车线满足新增货运量的装车需求。考虑到冯家川站地形及工程的复杂性,着重研究了外包既有装车线方案、与冯红车场立交疏解新建装车环线方案、既有车场对侧新建装车环线方案3种环型装车线布置形式。通过对比,认为既有车场对侧新建装车环线方案对既有车站及装车系统运营影响最小,预留了冯红铁路与兴保铁路双线贯通的条件,各车场高程一致,作业方便,交叉干扰少,研究后予以推荐。

关键词：重载铁路兴保铁路装车环线车站布置形式方案比选

Mechanisms of water block removal by surfactant micellar solutions in low permeability reservoirs

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Petroleum Exploration and Development 2022年第2期49卷 394-405页

作者： LI Junjian LIU Ben GUO Cheng SU Hang YU Fuwei ma mengqi WANG Lida JIANG Hanqiao State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China Research Institute of Petroleum Exploration&Development PetroChinaBeijing 100083China

The existing researches on surfactant micellar solutions mainly focus on the formulation optimization and core flooding test, and the types and mechanisms of cleanup additives suitable for low permeability reservoir remain unclear. The flowback efficiencies of different types of surfactant micellar solutions were evaluated by core experiments, a multi-level pore-throat system micromodel characterizing pore-throat structures of low permeability reservoir was made, and flooding and flowback experiments of brine and surfactant micellar solutions of different salinities were conducted with the micromodel to show the oil flowback process in micron pores under the effect of surfactant micellar solution visually and reveal the mechanisms of enhancing displacement and flowback efficiency of surfactant micellar solution. During the displacement and flowback of brine and low salinity surfactant micellar solution, many small droplets were produced, when the small droplets passed through pore-throats, huge percolation resistance was created due to Jamin’s effect, leading to the rise of displacement and flowback pressure differences and the drop of flowback efficiency. The surfactant micellar solutions with critical salinity and optimal salinity that were miscible with crude oil to form Winsor Ⅲ micro-emulsion didnot produce mass small droplets, so they could effectively reduce percolation resistance and enhance oil displacement and flowback efficiency.

关键词： low permeability reservoir cleanup additive cleanup mechanism surfactant microfluidic visualization experiment crude flowback

RefluxClassifier分离细颗粒的技术发展与应用前景

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有色金属（选矿部分） 2024年第1期 106-115页

作者：马梦绮张志远荆隆隆方佳豪李延锋中国矿业大学化工学院江苏徐州221116

矿石综采技术带来诸多便利的同时,也导致了矿石中细颗粒比例增多。细颗粒分离成为了国内外矿物加工领域面临的难题。由于细颗粒质量小、比表面积大、表面能高、容易团聚,进而难以有效分离。本世纪初,由澳大利亚学者Galvin所研制的Reflux... 详细信息

矿石综采技术带来诸多便利的同时,也导致了矿石中细颗粒比例增多。细颗粒分离成为了国内外矿物加工领域面临的难题。由于细颗粒质量小、比表面积大、表面能高、容易团聚,进而难以有效分离。本世纪初,由澳大利亚学者Galvin所研制的RefluxClassifier(回流分级机,简称RC)作为一种新型重力分选设备进入到矿物加工设备行列。该设备由液固流化床与倾斜通道组成,分为垂直段与倾斜段,具有操作简单、成本低廉和高效节能等优点。据研究,RC因其特殊的结构与工作机理可以有效解决细颗粒分离问题。本文首先归纳了国内外有关RC的理论研究,详细描述了RC倾斜段中颗粒在流体中的运动状态,阐明了倾斜通道内颗粒运动与流体流动特性之间的关系,简要分析了颗粒性质与流体之间的力与速度关系。此外,本文对目前现有RC的水速预测模型(经典动力学模型、经验模型、弱化粒度模型、平衡模型)进行了总结,并综合分析了各模型的适用范围。结合试验案例,介绍了RC在煤炭、黑金属、砂石骨料等领域的应用现状,举例分析不同试验条件下RC对细颗粒回收的分离情况。最后结合我国资源现状与现代设备发展趋势,提出如何深入优化RC分选理论模型、拓展更广阔的应用领域是国内外学者的长期研究目标,并展望RC在工业范围内的全面推广。

关键词： RefluxClassifier 细粒回收重力分选颗粒运动

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紧邻地铁的深基坑锚索支护结构施工技术

建设科技 2024年第12期 75-77页

作者：常子政马梦琪侯玉栋赵志浩梁伟建中建八局第二建设有限公司济南250014 河北工程技术学院石家庄050000

随着城市化建设加快,地下轨道线路高速发展,城区越来越多的高层建筑建设场地狭小、场区外交通人员流量大、地下隧道线路环境复杂,如何实现紧邻地铁深基坑支护施工质量及安全至关重要。本文针对深基坑边坡极限承载力问题,通过理论分析和... 详细信息

随着城市化建设加快,地下轨道线路高速发展,城区越来越多的高层建筑建设场地狭小、场区外交通人员流量大、地下隧道线路环境复杂,如何实现紧邻地铁深基坑支护施工质量及安全至关重要。本文针对深基坑边坡极限承载力问题,通过理论分析和现场试验对提高预应力锚索抗拔承载力方法进行研究,提出现场钻孔设备补焊钻头、严格控制水灰比、改用双套管施工工艺的方法,提高锚索抗拔承载力一次合格率。

关键词：基坑支护锚索双套管施工变形自动化监测

Collagen secretion screening in Drosophila supports a common secretory machinery and multiple Rab requirements

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Journal of Genetics and Genomics 2018年第6期45卷 299-313页

作者： Hongmei Ke Zhi Feng Min Liu Tianhui Sun Jianli Dai mengqi ma Lu-Ping Liu Jian-Quan Ni Jos Carlos Pastor-Pareja School of Life Sciences Tsinghua University School of Medicine Tsinghua University

Collagens are large secreted trimeric proteins making up most of the animal extracellular *** of collagen has been a focus of interest for cell biologists in recent years because collagen trimers are too large and rigid to fit into the COPII vesicles mediating transport from the endoplasmic reticulum（ER） to the Golgi. Collagen-specific mechanisms to create enlarged ER-to-Golgi transport carriers have been postulated, including cargo loading by conserved ER exit site（ERES） protein ***, we report an RNAi screening for genes involved in collagen secretion in Drosophila. In this screening, we examined distribution of GFP-tagged Collagen IV in live animals and found 88 gene hits for which the knockdown produced intracellular accumulation of Collagen IV in the fat body, the main source of matrix proteins in the larva. Among these hits, only two affected collagen secretion specifically：PH4 a EFB and Plod, encoding enzymes known to mediate posttranslational modification of collagen in the ER. Every other intracellular accumulation hit affected general secretion, consistent with the notion that secretion of collagen does not use a specific mode of vesicular transport, but the general secretory pathway. Included in our hits are many known players in the eukaryotic secretory machinery, like COPII and COPI components, SNAREs and Rab-GTPase regulators. Our further analysis of the involvement of Rab-GTPases in secretion shows that Rab1, Rab2 and Rab X3, are all required at ERES, each of them differentially affecting ERES morphology. Abolishing activity of all three by Rep knockdown, in contrast,led to uncoupling of ERES and Golgi. We additionally present a characterization of a screening hit we named trabuco（tbc）, encoding an ERES-localized TBC domain-containing Rab-GAP. Finally, we discuss the success of our screening in identifying secretory pathway genes in comparison to two previous secretion screenings in Drosophila S2 cells.

关键词： Collagen Ⅳ COPⅡ vesicles RNAi screening Secretory pathway Rab-GTPases ER exit site

玻璃纤维质量分数对尼龙6/玻璃纤维复合材料性能的影响

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辽宁石油化工大学学报 2024年第3期44卷 23-29页

作者：冯瑞祥马梦绮郎学彬胡跃鑫韩向艳徐宏伟辽宁石油化工大学石油化工学院辽宁抚顺113001 吉林省龙展新材料科技有限公司吉林长春130117

采用双螺杆挤出机制备了玻璃纤维(GF)增强尼龙6(PA6)复合材料,系统地研究了GF质量分数对PA6/GF复合材料的力学性能、热性能、密度、吸水性和加工流动性的影响。结果表明,PA6/GF复合材料的冲击强度、拉伸强度、弯曲强度、弯曲模量、密度... 详细信息

采用双螺杆挤出机制备了玻璃纤维(GF)增强尼龙6(PA6)复合材料,系统地研究了GF质量分数对PA6/GF复合材料的力学性能、热性能、密度、吸水性和加工流动性的影响。结果表明,PA6/GF复合材料的冲击强度、拉伸强度、弯曲强度、弯曲模量、密度和热变形温度均随着GF质量分数的增加而增加,而吸水率和熔融指数随着GF质量分数的增加而减小。形态结构显示,当GF质量分数为30%时,GF在PA6基体中得到了有效的包裹和分散。

关键词：玻璃纤维力学性能尼龙6

Unveiling the surface-interface properties of perovskite crystals and pivotal regulation strategies

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Nano Research 2024年第5期17卷 3950-3981页

作者： Qin Li Ziyu Wang Junjie ma mengqi Han Peng Gao Meng Cai Yiqiang Zhang Yanlin Song Shou Peng Henan Institute of Advanced Technology College of ChemistryZhengzhou UniversityZhengzhou 450001China Key Laboratory of Green Printing Institute of ChemistryChinese Academy of Sciences(ICCAS)Beijing 100190China China National Building material Group Co. Ltd.Beijing 100036China State Key Laboratory of Advanced Technology for Float Glass Beijing 100036China

Metal-halide perovskite solar cells have garnered significant research attention in the last decade due to their exceptional photovoltaic performance and potential for *** achieving remarkable power conversion efficiency of up to 26.1%,a substantial discrepancy persists when compared to the theoretical Shockley-Queisser(SQ)*** of the most serious challenges facing perovskite solar cells is the energy loss incurred during photovoltaic conversion,which affects the SQ limits and stability of the *** significant than the energy loss occurring in the bulk phase of the perovskite is the energy loss occurring at the ***,we provide a systematic overview of the physical and chemical properties of the ***,we delve into the underlying mechanism causing the energy deficit and structural degradation at the surface-interface,aiming to enhance the understanding of carrier transport processes and structural chemical ***,we systematically summarized the primary modulating pathways,including surface reconstruction,dimensional construction,and electric-field ***,we propose directions for future research to advance the efficiency of perovskite solar cells towards the radiative limit and their widespread commercial application.

关键词： perovskite solar cells surface-interface treatment defect modification dimensional design energy regulation heterojunction and homojunction

基于SPOC的翻转课堂教学模式在内科护理学教学中的应用研究

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中国高等医学教育 2024年第2期 80-82页

作者：李健芝胡丽伍春万艳平曾谷清李忠玉马梦琪莫文娟南华大学护理学院湖南衡阳421001

目的:探讨基于SPOC的翻转课堂教学模式在内科护理学本科教学中的应用及效果。方法:选取2018级两个教学班的护理专业本科生为研究对象,随机抽取一个教学班为试验组(n=67),采用基于SPOC的翻转课堂教学模式,另一个教学班为对照组(n=74),采... 详细信息

目的:探讨基于SPOC的翻转课堂教学模式在内科护理学本科教学中的应用及效果。方法:选取2018级两个教学班的护理专业本科生为研究对象,随机抽取一个教学班为试验组(n=67),采用基于SPOC的翻转课堂教学模式,另一个教学班为对照组(n=74),采用传统教学模式。比较两组学习成绩和自主学习能力,并调查试验组对教学效果的评价。结果:试验组的总评成绩、期中考试成绩、期末考试成绩均高于对照组(P<0.001)。试验组自主学习能力总量表及各分量表得分均高于对照组(P<0.05)。结论:在内科护理学教学中采用基于SPOC的翻转课堂教学模式,有利于提高护生的成绩和自主学习能力,提高教学效果。

关键词： SPOC 翻转课堂自主学习能力内科护理学

Development of a single transcript CRISPR/Cas9 toolkit for efficient genome editing in autotetraploid alfalfa

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The Crop Journal 2024年第3期12卷 788-795页

作者： Haixia Zhao Siyi Zhao Yingping Cao Xiping Jiang Lijuan Zhao Zhimeng Li mengqi Wang Ruijuan Yang Chuanen Zhou Zhaoming Wang Feng Yuan Dongmei ma Hao Lin Wenwen Liu Chunxiang Fu CAS Key Laboratory of Biofuels Shandong Provincial Key Laboratory of Energy GeneticsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101ShandongChina Shandong Energy Institute Qingdao 266101ShandongChina Qingdao New Energy Shandong Laboratory Qingdao 266101ShandongChina University of Chinese Academy of Sciences Beijing 100049China The Key Laboratory of Plant Development and Environmental Adaptation Biology Ministry of EducationSchool of Life SciencesShandong UniversityQingdao 266101ShandongChina Key Laboratory of Forage Breeding and Seed Production of Inner Mongolia Inner Mongolia M-Grass Ecology and Environment(Group)Co.Ltd.Hohhot 010016Inner MongoliaChina School of Ecology Environment Ningxia UniversityYinchuan 750021NingxiaChina Biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijing 100081China

Alfalfa(Medicago sativa.L.)is a globally significant autotetraploid legume forage ***,despite its importance,establishing efficient gene editing systems for cultivated alfalfa remains a formidable *** this study,we pioneered the development of a highly effective ultrasonic-assisted leaf disc transformation system for Gongnong 1 alfalfa,a variety widely cultivated in Northeast ***,we created a single transcript CRISPR/Cas9(CRISPR_2.0)toolkit,incorporating multiplex gRNAs,designed for gene editing in Gongnong *** Cas9 and gRNA scaffolds were under the control of the Arabidopsis ubiquitin-10 promoter,a widely employed polymeraseⅡconstitutive promoter known for strong transgene expression in *** assess the toolkit’s efficiency,we targeted PALM1,a gene associated with a recognizable multifoliate *** the CRISPR_2.0 toolkit,we directed PALM1 editing at two sites in the wild-type Gongnong *** indicated a 35.1%occurrence of editing events all in target 2 alleles,while no mutations were detected at target 1 in the transgenic-positive *** explore more efficient sgRNAs,we developed a rapid,reliable screening system based on Agrobacterium rhizogenes-mediated hairy root transformation,incorporating the visible reporter *** screening system demonstrated that most purple visible hairy roots underwent gene ***,sgRNA3,with an 83.0%editing efficiency,was selected using the visible hairy root *** anticipated,tetra-allelic homozygous palm1 mutations exhibited a clear multifoliate *** palm1 lines demonstrated an average crude protein yield increase of 21.5%compared to trifoliolate *** findings highlight the modified CRISPR_2.0 system as a highly efficient and robust gene editing tool for autotetraploid alfalfa.

关键词： Alfalfa Gene editing CRISPR_2.0 toolkit Hairy root system Tetra-allelic homozygous mutants