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寒冷地区电液制动器的油液黏度-时间模型及制动特性研究

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液压与气动 2024年第7期48卷 111-119页

作者：王泽河邢磊孙亚楠王磊魏福生魏建强河北农业大学机电工程学院河北保定071001 河北省智慧农业装备技术创新中心河北保定071001 河北省水利工程局集团有限公司河北石家庄050021 河北省大清河河务中心河北保定071051

针对寒冷地区电液制动器制动力和制动力矩不足等导致水闸制动系统发生溜车问题,基于液压油Vogel黏温模型以及当地温度变化数据,构建了油液黏度随时间变化的黏度-时间模型,并基于该模型对电液制动器制动过程中油液流动特性进行了研究,然... 详细信息

针对寒冷地区电液制动器制动力和制动力矩不足等导致水闸制动系统发生溜车问题,基于液压油Vogel黏温模型以及当地温度变化数据,构建了油液黏度随时间变化的黏度-时间模型,并基于该模型对电液制动器制动过程中油液流动特性进行了研究,然后对电液制动器制动性能进行了定量分析。结果表明:在制动过程中,电液制动器液压油压力主要分布在活塞底腔,且随着黏度增大而逐渐增大,当油液黏度为662.4 pa.s时,压力达到1.455×10^(-3)Mpa.电液制动器液压油在叶轮中心轴部位会出现涡流循环,其循环强度随着油液黏度的增加而逐渐增加;在给定工况下,该电液制动器的最小制动力为1098 N,最小制动力矩为274 N·m。而这一制动力矩已低于该电液制动器工作力矩范围,此时可以通过更换该月份黏度更小的液压油或增设预加热系统等措施来提高其制动力和制动力矩,从而实现正常制动。

关键词：电液制动器寒冷地区黏度-时间模型流场特性制动特性

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国际内分泌代谢杂志 2024年第4期44卷 232-238页

作者：张洁李英余红艳邸阜生王凤梅天津医科大学三中心临床学院天津市重症疾病体外生命支持重点实验室天津市人工细胞工程技术研究中心天津市肝胆疾病研究所天津300170 天津医科大学一中心临床学院天津300084

目的探讨2型糖尿病(T2DM)合并代谢相关性脂肪肝(MAFLD)患者体力活动水平(pa.和心肺适能(CRF)对心血管风险评分的影响,以期为改善此类患者心血管疾病预后提供理论基础。方法选取228例T2DM合并MAFLD患者,分为低pa.及中高pa.,比较两组患... 详细信息

目的探讨2型糖尿病(T2DM)合并代谢相关性脂肪肝(MAFLD)患者体力活动水平(pa.和心肺适能(CRF)对心血管风险评分的影响,以期为改善此类患者心血管疾病预后提供理论基础。方法选取228例T2DM合并MAFLD患者,分为低pa.及中高pa.,比较两组患者临床及生化指标、能量代谢指标、运动心肺指标及心血管疾病风险的差别,并通过相关及回归分析探讨除传统心血管疾病风险预测因素外,pa.CRF及其他因素对此类患者心血管疾病风险的影响。结果低pa.10年心血管疾病风险明显高于中高pa.,而最大摄氧量(VO_(2max))、无氧阈明显低于中高pa.,差异有统计学意义(P均pa.VO_(2max)呈明显相关性,线性回归分析显示pa.7项广泛焦虑障碍量表(GAD7)是影响VO_(2max)的独立相关因素,而第1秒最大呼气容积(FEV1)、分钟最大通气量(MVV)及VO_(2max)是影响10年心血管疾病风险的独立相关因素。结论体力活动的减少及心肺功能的下降是增加T2DM合并MAFLD患者心血管风险的重要影响因素。

关键词： 2型糖尿病代谢相关性脂肪性肝炎体力活动心肺适能心血管疾病风险

Reducing active layer thickness of polyamide composite membranes using a covalent organic framework interlayer in interfacial polymerization

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Chinese Journal of Chemical Engineering 2020年第4期28卷 1039-1045页

作者： Meidi Wang Weixiong Guo Zhongyi Jiang fusheng pa. State Key Laboratory of Petroleum Pollution Control CNPC Research Institute of Safety and Environmental TechnologyBeijing 102206China Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China

Polyamide(pa.-based thin-film composite membranes exhibit enormous potential in water purification,owing to their facile fabrication,decent performance and desirable ***,the thick pa.active layer with high transport resistance from the conventional interfacial polymerization hampers their *** controllable fabrication of a thin pa.active layer is essential for high sepa.ation efficiency but still ***,a covalent organic framework Tppa.1 interlayer was firstly deposited on a polyethersulfone(PES)substrate to reduce the thickness of pa.active layer in interfacial *** abundant pores of Tppa.1 increase the local concentration of amine monomers by adsorbing piperazine molecules,while hydrogen bonds between hydrophilic groups of Tppa.1 and piperazine molecules slow down their diffusion *** from those synergetic effects,the pa.active layer is effectively reduced from 200 nm to 120 *** optimizing Tppa.1 interlayer and pa.active layer,the water flux of resultant membranes can reach 171.35 L·m^-2·h^-1·Mpa.-1,which increased by 125.4%compa.ed with pa.PES membranes,while the rejection rates of sodium sulfate and dyes solution remained more than 90%and 99%,*** strategy may stimulate rational design of ultrathin pa.based nanofiltration membranes with high performances.

关键词： Thin film composite membranes Interfacial polymerization Covalent organic frameworks interlayer Nanofiltration

The political economy of climate change: the impa.se and way out

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Economic and Political Studies 2021年第3期9卷 315-335页

作者： fusheng Xie Han Cheng School of Economics and National Research Centre for Political Economy of Socialism with Chinese CharacteristicsRenmin University of ChinaBeijingChina Depa.tment of Economics Franklin&Marshall CollegeLancasterPAUSA

Mainstream economics attributes climate change to negativeexternalities of carbon emissions and the lack of climate propertyrights. Although market-based strategies such as emission tradingare widely implemented under the guideline of mainstream economics, there is no evidence that the accelerating trend of globalwarming has been contained. Marxian economists criticise thetheoretical point of depa.ture of the mainstream perspectiveabout climate change and climate governance, and propose analternative analytical framework focussing on the relationshipbetween climate and capital accumulation. Following the Marxianperspective, we discuss the subject, nature, strategy, and possibility of a popular climate movement that could serve as an alternative to the existing mainstream climate governance.

关键词： Climate change climate governance Marxian economics popular movement

聚乳酸非织造布植酸/壳聚糖/硼酸一浴法阻燃整理

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纺织学报 2023年第10期44卷 120-126页

作者：张广知杨甫生方进杨顺安徽工程大学纺织服装学院安徽芜湖241000

为实现聚乳酸非织造布的阻燃抗熔滴功能,以壳聚糖(CS)、植酸(pa.、无机硼酸(BA)为主要原料,采用一浴法对聚乳酸非织造布进行阻燃整理。借助傅里叶红外光谱仪、扫描电镜、X射线能谱仪和热重分析仪、垂直法织物燃烧性能测试仪等表征和评... 详细信息

为实现聚乳酸非织造布的阻燃抗熔滴功能,以壳聚糖(CS)、植酸(pa.、无机硼酸(BA)为主要原料,采用一浴法对聚乳酸非织造布进行阻燃整理。借助傅里叶红外光谱仪、扫描电镜、X射线能谱仪和热重分析仪、垂直法织物燃烧性能测试仪等表征和评价了聚乳酸非织造布的化学结构、表面形貌及表面元素分布、热稳定性能和阻燃性能。结果表明:聚乳酸非织造布经一浴法处理后,续燃、阴燃时间均为0 s,无熔滴,损毁长度仅为11.3 cm,极限氧指数为34.6%;壳聚糖、植酸、硼酸以及复合物共沉积覆盖在聚乳酸纤维上,且磷、硼、氮等元素质量分数分别达到5.26%、12.91%、4.26%;氮气气氛下,阻燃处理样起始分解温度降低了139.3℃,800℃时的残炭量达到14.57%;pa.CS/BA一浴法生物质阻燃体系提高了聚乳酸非织造布的阻燃抗熔滴效果和热稳定性,符合凝聚相阻燃机制。该生物质阻燃体系为聚乳酸纺织品提供了一种新的环保阻燃和抗熔滴的策略,具有较好的市场应用潜力。

关键词：聚乳酸纤维非织造布植酸壳聚糖阻燃整理一浴法

Experimental Study on the Mechanism for the Formation of Sn- bearing Granite in Northern Guangxi

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Acta Geologica Sinica(English Edition) 1994年第2期68卷 169-182,228页

作者： Liang Xiangji, Qiao Li, Wang fusheng and Yang Chonghui Institute of Geology, Chinese Academy of Geological Sciences, Beijing Institute of Geology Chinese Academy of Geological Sciences Beijing

Experimental results have proved that the Xuefengian Sn-bearing biotite granites were formed by remelting and recrystallization of the Proterozoic metamorphic rocks of the Sibao Group at 500× 105-2000× 105 pa.and 750-570℃ and further testified that the F- and B-bear-ing aqueous solution played an important pa.t in decreasing the formation temperature of the rocks. The results tally with the reality of the field geology. The authors have thus brought to light the mechanism for the formation of the Sn-bearing biotite granites and expounded the significance of their formation in the crust dynamics of South China.

关键词： experimental study Sn-bearing biotite granites formation mechanism northern Guangxi

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基于离子液体的聚合物材料化学解聚研究进展

高分子材料科学与工程 2017年第1期33卷 186-190页

作者：王婵宋修艳刘福胜青岛科技大学化工学院山东青岛266042

综述了近年来离子液体环境下高聚物材料化学降解回收相应产品的研究现状,重点介绍了聚碳酸酯(PC)、聚对苯二甲酸乙二醇酯(PET)、聚β-羟基丁酸酯(PHB)、聚乳酸(PLA)、尼龙6(pa.)及聚乙烯(PE)等材料在离子液体环境下的化学降解方法,同时... 详细信息

综述了近年来离子液体环境下高聚物材料化学降解回收相应产品的研究现状,重点介绍了聚碳酸酯(PC)、聚对苯二甲酸乙二醇酯(PET)、聚β-羟基丁酸酯(PHB)、聚乳酸(PLA)、尼龙6(pa.)及聚乙烯(PE)等材料在离子液体环境下的化学降解方法,同时分析了各种方法的优缺点。最后对离子液体用于聚合物化学降解行为的发展前景进行了展望。

关键词：离子液体聚合物材料化学解聚

Effects of viscosity on shock-induced damping of an initial sinusoidal disturbance

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Science China(Physics,Mechanics & Astronomy) 2010年第5期53卷 802-806页

作者： MA XiaoJuan1,LIU fusheng1 & JING FuQian2 1 College of Physical Science and Technology,Southwest Jiaotong University,Chengdu 610031,China 2 Laboratory for Shock Wave and Detonation Physics Research,Institute of Fluid Physics,Chinese Academy of Engineering Physics,Mianyang 621900,China College of Physical Science and Technology Southwest Jiaotong University Chengdu China Laboratory for Shock Wave and Detonation Physics Research Institute of Fluid Physics Chinese Academy of Engineering Physics Mianyang China

A lack of reliable data treatment method has been for several decades the bottleneck of viscosity measurement by disturbance amplitude damping method of shock *** this work the finite difference method is firstly applied to obtain the numerical solutions for disturbance amplitude damping behavior of sinusoidal shock front in inviscid and viscous *** water shocked to 15 Gpa.is taken as an example,the main results are as follows:(1) For inviscid and lower viscous flows the numerical method gives results in good agreement with the analytic solutions under the condition of small disturbance(a0/λ=0.02);(2) For the flow of viscosity beyond 200 pa.s(η=κ) the analytic solution is found to overestimate obviously the effects of *** is attributed to the unreal pre-conditions of analytic solution by Miller and Ahrens;(3) The present numerical method provides an effective tool with more confidence to overcome the bottleneck of data treatment when the effects of higher viscosity in experiments of Sakharov and flyer impa.t are expected to be analyzed,because it can in principle simulate the development of shock waves in flows with larger disturbance amplitude,higher viscosity,and complicated initial flow.

关键词： viscosity coefficient two-dimensional Eulerian flow shock front sinusoidal disturbance

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4800 t/d生产线节能降碳升级改造

水泥 2023年第11期 51-54页

作者：王福生沈红成吕正雄赵军葛洲坝老河口水泥有限公司湖北襄阳441800

针对4 800 t/d生产线存在的预热器运行阻力大、能耗高等问题进行了节能降碳升级改造,改后熟料产量达到了6 500 t/d以上,C_1出口温度308℃,C_1出口负压-5 150 pa.C_1出口粉尘浓度从124.5 g/Nm~3降低至64.9 g/Nm~3,熟料标准煤耗从107.72 k... 详细信息

针对4 800 t/d生产线存在的预热器运行阻力大、能耗高等问题进行了节能降碳升级改造,改后熟料产量达到了6 500 t/d以上,C_1出口温度308℃,C_1出口负压-5 150 pa.C_1出口粉尘浓度从124.5 g/Nm~3降低至64.9 g/Nm~3,熟料标准煤耗从107.72 kg/t降低至97.33 kg/t,实现了节能降碳的目标。

关键词：预热器节能降碳分解炉标准煤耗