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Experimental investigation on weak shock wave mitigation characteristics of flexible polyurethane foam and polyurea

Defence Technology（防务技术） 2024年第1期31卷 179-191页

作者： shiyu Jia Cheng Wang Wenlong Xu Dong ma Fangfang Qi State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Institute for Advanced Technology Shandong UniversityJinan250061China

In recent years,explosion shock wave has been considered as a signature injury of the current military conflicts.Although strong shock wave is lethal to the human body,weak shock wave can cause many more lasting consequences.To investigate the protection ability and characteristics of flexible materials and structures under weak shock wave loading,the blast wave produced by TNT explosive is loaded on the polyurethane foam with the density of 200.0 kg/m3(F-200)and 400.0 kg/m3(F-400),polyurea with the density of 1100.0 kg/m^(3)(P-1100)and structures composed of the two materials,which are intended for individual protection.Experimental results indicate that the shock wave is attenuated to weak pressure disturbance after interacting with the flexible materials which are not damaged.The shock wave protective capability of single-layer materials is dependent on their thickness,density and microscopic characteristics.The overpressure,maximum pressure rise rate and impulse of transmitted wave decrease exponentially with increase in sample thickness.For the same thickness,F-400 provides better protective capability than F-200 while P-1100 shows the best protective capability among the three materials.In this study,as the materials are not destroyed,F-200 with a thickness more than10.0 mm,F-400 with a thickness more than 4.0 mm,and P-1100 with a thickness more than 1.0 mm can attenuate the overpressure amplitude more than 90.0%.Further,multi-layer flexible composites are designed.Different layer layouts of designed structures and layer thickness of the single-layer materials can affect the protective performance.Within the research range,the structure in which polyurea is placed on the impact side shows the optimal shock wave protective performance,and the thicknesses of polyurea and polyurethane foam are 1.0 mm and 4.0 mm respectively.The overpressure attenuation rate reached maximum value of 93.3%and impulse attenuation capacity of this structure are better than those of single-layer polyurea and polyurethane foam with

关键词： Free-field explosion Weak shock wave mitigation Polyurea Polyurethane foam Multi-layered composites

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Ammonia storage and slip under steady and transient state in close-coupled SCR

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Journal of Environmental Sciences 2024年第4期138卷 470-481页

作者： shiyu Liu Zhaohuan Zhang Zexian Guo Boyuan Wang Buyu Wang Xiao ma Shijin Shuai State Key Laboratory of Automotive Safety and Energy Tsinghua UniversityBeijing 100084China Institute for Aero Engine Tsinghua UniversityBeijing 100084China

The close-coupled selective catalytic reduction(cc-SCR)catalyst is an effective technology to reduce tailpipe NOx emission during cold start.This paper investigated the optimal ammonia storage under steady and transient state in the cc-SCR.The study showed that a trade-off between NOx conversion efficiency and ammonia slip is observed on the pareto solutions under steady state,and the optimal ammonia storage is calculated with ammonia slip less than 10μL/L based on the ChinaⅥemission legislation.The rapid temperature increase will lead to severe ammonia slip in the transient test cycle.A simplified 0-D calculation method on ammonia slip under transient state is proposed based on kinetic model of ammonia adsorption and desorption.In addition,the effect of ammonia storage,catalyst temperature and temperature increasing rate on ammonia slip are analyzed.The optimal ammonia storage is calculated with maximum ammonia slip less than 100μL/L according to the oxidation efficiency of ammonia slip catalyst(ASC)downstream cc-SCR.It was found that the optimal ammonia storage under transient state is much lower than that under steady state in cc-SCR at lower temperature,and a phase diagram is established to analyze the influence of temperature and temperature increasing rate on optimal ammonia storage.

关键词： Close-coupled SCR Ammonia storage and slip Steady and transient state Generic algorithm

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Two-step continuous flow process of sodium tanshinone ⅡA sulfonate using a 3D circular cyclone-type microreactor

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Chinese Chemical Letters 2024年第1期35卷 290-294页

作者： maolin Sun Chaoming Liang Liming Cao Yaguo Wang Jiasheng Yang shiyu Hou Wei Yu Yueyue ma Ruihua Cheng Jinxing Ye School of Biomedical and Pharmaceutical Sciences Guangdong University of TechnologyGuangzhou 510006China School of Pharmacy East China University of Science and TechnologyShanghai 200237China School of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Shanghai No.1 Biochemical&Pharmaceutical Co. Ltd.Shanghai 200080China

A sustainable and practical process is presented for the direct synthesis of sodium tanshinone IIA sulfonate(STS).Our approach was inspired by the well-established and industrially applied batch synthetic route for STS production.We constructed a telescoped two-step continuous flow platform.This involved a continuous tanshinone IIA sulfonation and in-line salt formation.For the setup,we constructed a 3D circular cyclone-type microreactor using femtosecond laser micromachining.Compared to the 68%yield for 2 h in batch,the two-step continuous flow had an STS yield of 90%,achieved for a total residence time ofmal conditions.The proposed continuous flow method vastly simplified the operation and improved procedural safety,while significantly reducing the required acid content and wastewater production.

关键词： Continuous flow Sodium tanshinone IIA sulfonate Cardiovascular Microreactor Green chemistry

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Formation mechanisms,potentials and exploration practices of large lithologic gas reservoirs in and around an intracratonic rift:Taking the Sinian-Cambrian of Sichuan Basin as an example

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Petroleum Exploration and Development 2022年第3期49卷 530-545页

作者： WEI Guoqi YANG Wei XIE Wuren SU NanX IE Zengye ZENG Fuying ma shiyu JIN Hui WANG Zhihong ZHU Qiuying HAO Cuiguo WANG Xiaodan Research Institute of Petroleum Exploration&Development PetroChinaBeijing 100083China

By examining structures,sediments,reservoirs and accumulation assemblages in the Deyang-Anyue rift and its surrounding area,four new understandings are obtained.First,during the initiation period of Deyang-Anyue rift,multiple groups of faults developed in the rift due to the effect of tensile force,bringing about multiple mound and shoal belts controlled by horsts in the second member of the Sinian Dengying Formation;in the development stage of the rift,the boundary faults of the rift controlled the development of mound and shoal belts at the platform margin in the fourth member of Dengying Formation;during the shrinkage period of the rift,platform margin grain shoals of the Cambrian Canglangpu Formation developed in the rift margin.Second,four sets of large-scale mound and shoal reservoirs in the second member of Dengying Formation,the fourth member of Dengying Formation,Canglangpu Formation and Longwangmiao Formation overlap with several sets of source rocks such as Qiongzhusi Formation source rocks and Dengying Formation argillaceous limestone or dolomite developed inside and outside the rift,forming good source-reservoir-cap rock combinations;the sealing of tight rock layers in the lateral and updip direction results in the formation model of large lithologic gas reservoirs of oil pool before gas,continuous charging and independent preservation of each gas reservoir.Third,six favorable exploration zones of large-scale lithologic gas reservoirs have been sorted out through comprehensive evaluation,namely,mound and shoal complex controlled by horsts in the northern part of the rift in the second member of Dengying Formation,isolated karst mound and shoal complex of the fourth member of Dengying Formation in the south of the rift,the superimposed area of multi-stage platform margin mounds and shoals of the second and fourth members of Dengying Formation and Canglangpu Formation in the north slope area,the platform margin mounds and shoals of the second and fourth members of Dengying Formation in the west side of

关键词： intracratonic rift large lithologic gas reservoir accumulation mechanism Sichuan Basin Sinian-Cambrian Deying-Anyue rift mound and shoal belt

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中国学生英语核心句法习得“瓶颈”:来自WH-疑问句的证据

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外语教学 2024年第3期45卷 51-58页

作者：马拯吴诗玉上海大学外国语学院

本研究使用语法判断测试任务,探讨何种WH-疑问句的转换规则构成我国学生英语核心句法习得的“瓶颈”。高一、高三和大学生三个不同层次共214名学习者参加了本次实验,混合效应模型拟合的结果显示,是否借助助动词来构成WH-疑问句是中国学... 详细信息

本研究使用语法判断测试任务,探讨何种WH-疑问句的转换规则构成我国学生英语核心句法习得的“瓶颈”。高一、高三和大学生三个不同层次共214名学习者参加了本次实验,混合效应模型拟合的结果显示,是否借助助动词来构成WH-疑问句是中国学生WH-疑问句习得的“瓶颈问题”,其中,宾语疑问句的助动词缺失和主语疑问句的助动词冗余是WH-疑问句习得最“顽固的障碍”,即这个句法转换规则不仅比别的规则更难学,而且持续性地难学,很难随着学习者的语言水平以及学习经历的增加而提高。从基于使用的二语习得观看,突显度低可能是造成这一转换规则难学的主要原因,而从原则与参数理论来看,也可能是因为二语习得的参数重置是一件极复杂的事情,有些参数重置难以完成。最后,本文还讨论了研究发现的教学启示。

关键词： WH-疑问句移位现象主语—助动词倒装语法判断任务

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Single-cell manipulation by two-dimensional micropatterning

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Journal of Innovative Optical Health Sciences 2024年第1期17卷 45-59页

作者： Xuehe ma Haimei Zhang shiyu Deng Qiushuo Sun Qingsong Hu Yuhang Pan Fen Hu Imshik Lee Fulin Xing Leiting Pan The Key Laboratory of Weak-Light Nonlinear Photonics of Education Ministry School of Physics and TEDA Institute of Applied Physics Nankai University Tianjin 300071P.R.China State Key Laboratory of Medicinal Chemical Biology Frontiers Science Center for Cell Responses College of Life Sciences Nankai University Tianjin 300071P.R.China Collaborative Innovation Center of Extreme Optics Shanxi University TaiyuanShanxi 030006P.R.China Shenzhen Research Institute of Nankai University Shenzhen Guangdong 518083P.R.China

Cells are highly sensitive to their geometrical and mechanical microenvironment that directly regulate cell shape,cytoskeleton and organelle,as well as the nucleus morphology and genetic expression.The emerging two-dimensional micropatterning techniques offer powerful tools to construct controllable and well-organized microenvironment for single-cell level investigations with qualitative analysis,cellular standardization,and in vivo environment mimicking.Here,we provide an overview of the basic principle and characteristics of the two most widely-used micropatterning techniques,including photolithographic micropatterning and soft lithography micropatterning.Moreover,we summarize the application of micropatterning technique in controlling cytoskeleton,cell migration,nucleus and gene expression,as well as intercellular communication.

关键词： Two-dimensional micropatterning cytoskeleton cell migration extracellular matrix intercellular communication gene expression

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从国家身份维度透视伊朗妇女政策

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阿拉伯世界研究 2024年第3期 107-130,159,160页

作者：郝诗羽马洋洋宁夏大学阿拉伯学院(中国阿拉伯国家研究院) 银川750001

伊朗伊斯兰共和国建国后,在霍梅尼什叶派现代伊斯兰主义的指导下,伊朗的国家身份被赋予了“宗教与世俗”的二元属性,伊朗政府的妇女政策随之发生了转向。霍梅尼时期,在“全盘伊斯兰化”的意识形态下,妇女政策被确定了以宗教思想为统领... 详细信息

伊朗伊斯兰共和国建国后,在霍梅尼什叶派现代伊斯兰主义的指导下,伊朗的国家身份被赋予了“宗教与世俗”的二元属性,伊朗政府的妇女政策随之发生了转向。霍梅尼时期,在“全盘伊斯兰化”的意识形态下,妇女政策被确定了以宗教思想为统领的基调。后霍梅尼时期,伊朗政坛单极格局消失,伊朗各方政治力量都尝试重塑宗教与世俗的关系来调整国家身份,妇女政策也随之发生了明显的阶段性变化。基于此,从伊朗国家身份维度解读妇女政策,可为理解伊朗妇女问题提供参考。首先,伊朗国家身份的宗教内核确定了妇女政策的起点,也框定了妇女政策改革的空间。其次,伊朗国家身份调整引发的政治斗争打断了妇女政策的连贯改革,使妇女政策缺乏长效性。最后,伊朗国家身份的二元格局,凸显了妇女发展世俗导向与妇女政策宗教底色间的张力,导致伊朗妇女问题频发。

关键词：伊朗国家身份妇女政策妇女发展

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基于轴压构件稳定系数的简支钢梁弯扭屈曲极限弯矩计算方法

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建筑结构学报 2024年第4期45卷 166-176页

作者：刘占科宋诗羽马张永周绪红兰州大学西部灾害与环境力学教育部重点实验室甘肃兰州730000 兰州大学土木工程与力学学院甘肃兰州730000 甘肃省科工建设集团有限公司甘肃兰州730300 重庆大学土木工程学院重庆400044

为了解决现行设计标准中钢梁弯扭屈曲极限弯矩计算方法在适用范围和计算精度上存在的问题,提出了基于理想轴压构件整体屈曲临界荷载的理想钢梁弹性弯扭屈曲临界弯矩计算式,并进一步提出了基于轴压构件稳定系数的简支钢梁弯扭屈曲极限弯... 详细信息

为了解决现行设计标准中钢梁弯扭屈曲极限弯矩计算方法在适用范围和计算精度上存在的问题,提出了基于理想轴压构件整体屈曲临界荷载的理想钢梁弹性弯扭屈曲临界弯矩计算式,并进一步提出了基于轴压构件稳定系数的简支钢梁弯扭屈曲极限弯矩计算方法。采用124个热轧H型钢梁试件、80个焊接梁试件、2个薄腹梁试件共计206个钢梁试件弯扭屈曲极限弯矩的试验结果,检验了方法的适用范围及计算精度,并与GB 50017—2017《钢结构设计标准》中的方法进行了对比。研究表明:对于206个钢梁试件,基于轴压构件稳定系数的计算方法较GB 50017—2017方法的适用范围更广,且与已有文献的计算精度相当;对于7个单轴对称工字形截面焊接高强钢梁试件,基于轴压构件稳定系数的计算方法略偏安全且精度高,而GB 50017—2017中的方法偏不安全;对于44个荷载工况不包含在GB 50017—2017中的钢梁试件,建议方法所得极限弯矩计算值与实测值之比的均值、标准差分别为0.908、0.125,精度较高且偏于安全。

关键词：简支钢梁弯扭屈曲极限弯矩临界弯矩轴压构件稳定系数

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HPLC多指标成分定量结合化学计量学、加权TOPSIS模型评价不同产地肺形草质量

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现代药物与临床 2024年第5期39卷 1176-1183页

作者：张立群马诗瑜冯恺徐虹上海交通大学医学院附属瑞金医院药剂科上海200025 上海中医药大学上海200032

目的评价不同产地肺形草的质量差异。方法采用HPLC法测定肺形草中马钱苷酸、莫诺苷、獐牙菜苦苷、龙胆苦苷、芒果苷、异荭草苷、异牡荆素、去甲基雏菊叶龙胆酮、当药黄素、3,6,8-三羟基-1-甲基呫吨酮、山楂酸和熊果酸,对多指标成分测定... 详细信息

目的评价不同产地肺形草的质量差异。方法采用HPLC法测定肺形草中马钱苷酸、莫诺苷、獐牙菜苦苷、龙胆苦苷、芒果苷、异荭草苷、异牡荆素、去甲基雏菊叶龙胆酮、当药黄素、3,6,8-三羟基-1-甲基呫吨酮、山楂酸和熊果酸,对多指标成分测定结果进行主成分分析、正交偏最小二乘法-判别分析,建立加权优劣解距离模型评估。结果16批肺形草明显聚集为3类;马钱苷酸、莫诺苷、3,6,8-三羟基-1-甲基呫吨酮、熊果酸、当药黄素和芒果苷是影响肺形草质量的主要潜在标志物;浙江和江苏产肺形草整体质量较好。结论建立的方法控制模式简单、评价模型科学合理,可用于肺形草质量评价。

关键词：肺形草钱苷酸莫诺苷獐牙菜苦苷龙胆苦苷芒果苷异荭草苷异牡荆素去甲基雏菊叶龙胆酮当药黄素 3 6 8-三羟基-1-甲基呫吨酮山楂酸熊果酸高效液相色谱主成分分析正交偏最小二乘法-判别分析加权优劣解距离模型

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Hydrocarbon accumulation and exploration prospect of mound-shoal complexes on the platform margin of the fourth member of Sinian Dengying Formation in the east of Mianzhu-Changning intracratonic rift, Sichuan Basin, SW China

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Petroleum Exploration and Development 2020年第6期47卷 1262-1274页

作者： YANG Wei WEI Guoqi XIE Wuren JIN Hui ZENG Fuying SU Nan SUN Ai ma shiyu SHEN Juehong WU Saijun Research Institute of Petroleum Exploration&Development PetroChinaBeijing 100083China

Drilling,seismic and logging data were used to evaluate the hydrocarbon accumulation conditions of the mound-shoal complexes in the platform margin of the fourth member of Sinian Dengying Formation in the east side of the Mianzhu-Changning intracratonic rift in the Sichuan Basin.The four understandings are:(1)The platform margin belt of the Deng 4 Member can be divided into three sections,northern,middle and southern;the middle section is at the core of the Gaoshiti-Moxi paleouplift and the structural high now,while the southern and northern sections are at the slope of the paleouplift and the structural lows now;the three sections have similar development characteristics and reservoir features of platform margin mound-shoal complex.(2)In the margin of the east side of the rift,there are several faults nearly perpendicular to the platform margin belt,the faults divide the platform margin belt into rugged paleo-landform,and the high part developed platform margin mound-shoal complexes and the reservoirs are good in physical properties,while the low part developed inter-beach depression and no mound-shoal complexes,where the reservoirs are poor in physical properties.(3)The six groups of faults nearly perpendicular to the platform margin belt divide the platform margin belt into seven large mound-shoal complexes which have similar hydrocarbon accumulation conditions and accumulation evolution process and are rich in petroleum.(4)The inter shoal depressions between the mound-shoal complexes are characterized by tighter lithology,which can block the updip direction of the mounds and shoals at the lower part of the slope of the paleouplift and are favorable for the later preservation of mound-shoal gas reservoirs.This has been proved by Well Jiaotan 1 and Heshen 2 drilled successfully.The mound-shoal complexes on the platform margin of the structural slope area have a good exploration prospect.

关键词： Sichuan Basin fourth member of Sinian Dengying Formation mound-shoal complex at platform margin low structural area hydrocarbon accumulation exploration prospect

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