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Ion Current Rectifier Switch by the Different Combination Modes of Single Conical Nanopores Membrane

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Ion Current Rectifier Switch by the Different Combination Mo...

Microstructure evolution and phase transformation of the mushy zone in a quenchedβ-solidifying TiAl alloy

全国第八届有机固体电子过程暨华人有机光电功能材料学术讨论会

作者： xu hou~b,fuqiang nie~(a,*),lei jiang~a (a Center of Molecular Sciences,Institute of Chemistry,Chinese Academy of Sciences,beijing 100190) (b National Center for Nanoscience and Nanotechnology,beijing 100190)

Nowadays,the ionic rectification properties of the single nanopore prepared by ion track-etching technique has been studied in comparison with the properties of various ion *** nanopores in these polymer membranes with various surface charges have been shown to act as ion rectifiers,due to the structural asymmetry. Even though the ion transport properties of single nanopore systems have been well studied,how to

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Journal of Materials Science & Technology 2024年第2期169卷 28-41页

作者： fuqiang Zhang Xianfei Ding Leming xu Xin Feng Hai Nan Jianping He Yongfeng Liang Junpin Lin State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Cast Titanium Alloy R&D Center Beijing Institute of Aeronautical MaterialsBeijing 100095China

This study investigates the phase constitutions and transformations that occur in the mushy zone and in the adjacent phase fields of a directionally solidified Ti-44Al-8Nb-1Cr alloy via quenching *** results indicate that the mushy zone consists of unmeltedβdendrites and interdendritic liquid,whose formation can be attributed to the difference in melting point aroused by local heterogeneity in ***βdendrite is composed of numerous subgrains with various *** quenching,theβdendrite transforms into Widmanstättenαvia a precipitation reaction,owing to the decreasing cooling rate caused by heat transfer from the surrounding ***,after quenching,the interdendritic liquid is transformed intoγ*** the singleβphase field and the lower part of the mushy zone,a massive transformation ofβtoγ***,in theβ+αphase field,bothβandαphases are retained to ambient *** the heating process,the transformation ofα→βgives rise to the formation ofβvariants,which affects the orientation ofβdendrites in the mushy *** growth kinematics of theα→βtransformation was elucidated,revealing the preferential growth directions of111and112forβ***,this study presents an illustration of the formation process of the mushy zone and the microstructural evolution during the heating and quenching process.

关键词： Titanium aluminides Mushy zone Quenching Electron backscattering diffraction Phase transformation

A double-layer radiative cooling coating that utilizes the refractive index difference between layers to achieve extremely high solar reflectivity

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Science China Technological Sciences 2024年第10期67卷 3182-3189页

作者： WANG fuqiang LI ChunZhe YANG ZhenNing XIE WeiXin LI Xiang xu ZengHui YAN YuYing CHENG ZiMing School of Energy Science and Engineering Harbin Institute of Technology School of New Energy Harbin Institute of Technology at Weihai China Construction Eco-Environmental Protection Technology Co. Ltd. Faculty of Engineering University of Nottingham

Passive daytime radiative cooling（PDRC） technology has great potential in reducing cooling energy consumption. In order to further improve the spectral performance of PDRC coatings, current researchers mostly focus on the selection and size design of functional particles, while ignoring the optical properties enhancement effect caused by the interlayer binder. In this study, based on the principle that the refractive index difference between layers enhanced the backscattering performance of the solar spectrum, we proposed and manufactured a double-layer PDRC coating with polyvinylidene difluoride（PVDF） as the filmforming material in the upper layer and polydimethylsiloxane（PDMS） as the film-forming material in the lower layer, both filled with Al2O3and SiO2particles. The double-layer PDRC coating exhibited excellent spectral performance that a high solar reflectivity of 98% and an emissivity of 0.95 at the “atmospheric window” band. In comparison, the solar spectrum reflectivity of the single-layer PDRC coatings based on PVDF and PDMS of the same thickness was 95% and 94.7%, respectively. Outdoor tests showed that the PDRC coating achieved a temperature decrease of up to 7.1℃ under direct sunlight at noon time. In addition, the PDRC coating had excellent weather resistance, water resistance, and other basic properties. This article opens up a new idea and provides methodological guidance for the design of double-layer PDRC coatings.

关键词： double-layer radiative cooling coating spectral modulation interlayer refractive index solar energy radiative transfer

Functionalized lipid nanoparticles modulate the blood-brain barrier and eliminate α-synuclein to repair dopamine neurons

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Asian Journal of Pharmaceutical Sciences 2024年第2期19卷 120-135页

作者： Xiaomei Wu Renxiang Yuan Yichong xu Kai Wang Hong Yuan Tingting Meng fuqiang Hu Department of Pharmacy Ruijin HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 200000China College of Pharmaceutical Science Zhejiang UniversityHangzhou 310058China Jinhua Institute of Zhejiang University Jinhua 321299China

The challenge in the clinical treatment of Parkinson's disease lies in the lack of disease-modifying therapies that can halt or slow down the progression. Peptide drugs, such as exenatide (Exe), with potential disease-modifying efficacy, have difficulty in crossing the blood-brain barrier (bbb) due to their large molecular weight. Herein, we fabricate multi-functionalized lipid nanoparticles (LNP) Lpc-boSA/CSO with bbb targeting, permeability-increasing and responsive release functions. borneol is chemically bonded with stearic acid and, as one of the components of Lpc-boSA/CSO, is used to increase bbb permeability. Immunofluorescence results of brain tissue of 15-month-old C57bL/6 mice show that Lpc-boSA/CSO disperses across the bbb into brain parenchyma, and the amount is 4.21 times greater than that of conventional LNP. Motor symptoms of mice in Lpc-boSA/CSO-Exe group are significantly improved, and the content of dopamine is 1.85 times (substantia nigra compacta) and 1.49 times (striatum) that of PD mice. α-Synuclein expression and Lewy bodies deposition are reduced to 51.85% and 44.72% of PD mice, respectively. Immunohistochemical mechanism studies show AKT expression in Lpc-boSA/CSO-Exe is 4.23 times that of PD mice and GSK-3β expression is reduced to 18.41%. Lpc-boSA/CSO-Exe could reduce the production of α-synuclein and Lewy bodies through AKT/GSK-3β pathway, and effectively prevent the progressive deterioration of Parkinson's disease. In summary, Lpc-boSA/CSO-Exe increases the entry of exenatide into brain and promotes its clinical application for Parkinson's disease therapy.

关键词： blood-brain barrier Lipid nanoparticles brain delivery facilitation α-Symuclein Parkinson's disease

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PVA/EG导电水凝胶及其应变传感性能

功能材料 2024年第7期55卷 7098-7104页

作者：许啸尹富强李赵春南京林业大学机械电子工程学院南京210037

作为柔性传感器的优良材料,导电水凝胶在人体可穿戴设备领域具有广泛的应用前景。将水凝胶基底聚乙烯醇(PVA)与乙二醇(EG)混合,制备了几种不同PVA质量比的PVA/EG导电水凝胶。针对10%、20%、30%PVA/EG水凝胶进行了结构和形态的表征,其中2... 详细信息

作为柔性传感器的优良材料,导电水凝胶在人体可穿戴设备领域具有广泛的应用前景。将水凝胶基底聚乙烯醇(PVA)与乙二醇(EG)混合,制备了几种不同PVA质量比的PVA/EG导电水凝胶。针对10%、20%、30%PVA/EG水凝胶进行了结构和形态的表征,其中20%PVA/EG水凝胶的相对背景强度和晶体含量较高,且表面孔隙最多。通过万能材料试验机对20%PVA/EG导电水凝胶试样进行拉伸和压缩,测试了灵敏度、线性度、响应时间、稳定性和温度可靠性等传感性能。结果表明,导电水凝胶灵敏度系数最高达到0.74,线性相关系数达到0.987,响应时间低至80 ms,50次15%循环拉伸时的相对电阻变化基本恒定,且试样在-20℃低温下仍可正常工作。最后,将导电水凝胶试样粘贴在手指、脊椎和足部等人体不同部位,进行了运动试验,验证了该导电水凝胶在各类人体运动监测中的可行性。

关键词：水凝胶传感性能柔性传感器运动监测

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钢渣-矿渣基胶凝材料的协同水化机理

建筑材料学报 2024年第4期27卷 366-374页

作者：南雪丽杨旭张宇唐维斌张富强兰州理工大学材料科学与工程学院甘肃兰州730050 兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室甘肃兰州730050 甘肃省交通规划勘察设计院股份有限公司甘肃兰州730030

通过胶砂强度试验及X射线衍射仪(XRD)、热失重分析(TG-DTG)、扫描电镜-能谱仪(SEM-EDS)等微观测试技术,对不同配合比钢渣-矿渣基胶凝材料的力学性能、水化产物及其水化硬化过程进行了研究.结果表明:当胶凝材料的n(CaO+MgO)/n(SiO2+Al2O3... 详细信息

通过胶砂强度试验及X射线衍射仪(XRD)、热失重分析(TG-DTG)、扫描电镜-能谱仪(SEM-EDS)等微观测试技术,对不同配合比钢渣-矿渣基胶凝材料的力学性能、水化产物及其水化硬化过程进行了研究.结果表明:当胶凝材料的n(CaO+MgO)/n(SiO2+Al2O3)=0.90时,其水化后期有较多的水化硅酸钙、水化铝酸钙凝胶生成,微观结构更加致密,力学性能表现最优,28 d抗压强度和抗折强度分别达到20.20、7.25 MPa;pH值的变化反映出协同水化效应的关键在于钢渣活性矿物的溶解和矿渣的二次火山灰反应,钢渣和矿渣的最佳配合比可以保证水化程度有较高的水平.

关键词：钢渣高炉矿渣胶凝材料协同水化效应水化反应

干热岩长期生产过程中天然裂缝损伤对导流能力演变影响研究

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石油科学通报 2024年第3期9卷 465-475页

作者：许富强宋先知石宇李爽中国石油大学(北京)石油工程学院北京102249 中国石油大学(北京)油气资源与工程全国重点实验室北京102249 西南交通大学地球科学与工程学院成都611756

干热岩型地热是我国地热资源的重要组成部分,其开发利用对实现“双碳”目标具有重要意义。干热岩储层岩体以花岗岩为主,因其岩性致密,通常采用增强型地热系统(EGS)进行开发。作为循环工质流动换热的主要通道,人工裂缝和天然裂缝形变将... 详细信息

干热岩型地热是我国地热资源的重要组成部分,其开发利用对实现“双碳”目标具有重要意义。干热岩储层岩体以花岗岩为主,因其岩性致密,通常采用增强型地热系统(EGS)进行开发。作为循环工质流动换热的主要通道,人工裂缝和天然裂缝形变将造成导流能力演变,进而影响热储取热性能。现有导流能力研究对象多为人工裂缝,且多围绕基质弹性变形开展,并未考虑天然裂缝损伤影响。为揭示天然裂缝损伤作用效果,团队自主研发设计了高温高压岩心注采多场耦合实验平台,分析论证了实验系统的可靠性,设计了对应实验方案与实验流程。采用天然裂缝贯穿岩样,研究了常温下注采压差随排量和围压的变化规律,分析了高温下天然裂缝损伤特征,对比了不同排量,温差和注入方式下天然裂缝损伤对导流能力演变的影响。实验表明,冷流体注入导致天然裂缝体积较初始时刻显著增加,且破坏方式以弱胶结失效为主,在无围压条件下,损伤将引起裂缝隙宽和缝长增大,提升裂缝连通性,有助于改变裂缝导流能力,故压裂和取热方案设计中应对天然裂缝加以考虑;注采压差随围压和排量增大而增加,最大增幅可达0.6 MPa;高温生产下,注采压差改变量和导流能力演化率变化量最大值分别可达1.11 MPa和26.59%。较大排量和温差下,裂缝损伤特征更为明显。相较于连续注入,间歇注入方式下裂缝损伤程度更为显著。利用灰色关联分析得到了主控因素为温差,即热应力是造成裂缝附加导流能力演变的主要原因。本研究证明了天然裂缝损伤在干热岩长期生产过程中分析的必要性,为工程现场施工提供了一定指导。

关键词：干热岩长期开采导流能力演变天然裂缝岩石损伤

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Reviews and prospects of human factors research on curve driving

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第5期10卷 808-834页

作者： lei Han Zhigang Du Haoran Zheng fuqiang xu Jialin Mei School of Transportation and Logistics Engineering Wuhan University of TechnologyWuhan 430063China Engineering Research Center of Transportation Information and Safety Ministry of EducationWuhan 430063China

In order to fully understand the research progress of human factors and traffic safety in curve driving,from the perspective of driver-vehicle-road-environment dynamic traffic system,this paper explored the current research status and development trend of human factors of curve driving,and displayed the development process and structural relationship of human factors research of curve driving by using scientific knowledge *** the core collection database of Web of Science,1408 English literatures related to human factors research of curve driving published from 2012 to 2022(as of October 1,2022)were obtained,and the literatures in this field were sorted and analyzed based on the VOSviewer visualization *** results show that China,Tongji University and Accident Analysis and Prevention are the country,institution and journal with the largest contribution rate in the field of human factors research on curve ***-citation analysis shows that the research contents in this field are divided into 5 clusters:driver’s visual characteristics,risk of collision,vehicle dynamics characteristics,the influence of traffic engineering facilities on driving behavior,selection of driving *** co-occurrence analysis of keywords shows that the topics of curve geometry design and vehicle dynamics,driving behavior and risk,driving speed and safety,behavior prediction and intervention measures are the current research hotspots in the research *** is found that the development trend of traffic safety improvement in curves is to construct a continuous,consistent,multi-level visual reference frame conforming to driving expectation through visual guiding technology,and summarizes the technical concept of linear visual *** study can provide a reference for the study of human factors of curve driving.

关键词： Traffic engineering Human factors Curve driving bibliometric analysis Visualization VOSviewer

真空气雾化法制备AlSi10Mg粉末参数优化及打印态组织性能研究

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精密成形工程 2024年第2期16卷 96-103页

作者：蒋保林蒋崴许荣玉陈烜吕复强赵永柱付珂陈正江苏威拉里新材料科技有限公司江苏徐州221000 中国矿业大学材料与物理学院江苏徐州221000 常熟天地煤机装备有限公司江苏苏州215500

目的探究利用真空气雾化法制备AlSi10Mg球形粉末过程中各参数对粉末质量的影响,以得到最佳的制粉工艺参数。以制备的粉末进行增材制造,研究块体组织及其力学性能。方法针对制备的球形粉末,采用扫描电镜(SEM)观察粉末的球形度及其内部组... 详细信息

目的探究利用真空气雾化法制备AlSi10Mg球形粉末过程中各参数对粉末质量的影响,以得到最佳的制粉工艺参数。以制备的粉末进行增材制造,研究块体组织及其力学性能。方法针对制备的球形粉末,采用扫描电镜(SEM)观察粉末的球形度及其内部组织。通过分析球形粉末的平均粒径与粒度分布区间总结最优制粉参数。针对以球形粉末增材制造出的沉积态样品,采用X射线衍射仪(XRD)、扫描电镜(SEM)研究其微观组织形貌并通过拉伸试验研究其力学性能。结果真空气雾化法制备出的粉末表面光洁且球形度良好,同时粉末平均粒径随雾化压力的增大呈现先减小后增大的趋势并在4.0 MPa时粒径最小,且与环孔喷嘴相比,环缝喷嘴制备出的粉末粒径更小。粉末内部组织由胞状晶与树枝晶构成。通过SLM制备的沉积态样品组织以沿沉积方向的枝晶为主,该样品的力学性能较优异,断裂方式主要为沿晶断裂。结论在使用真空气雾化法制备增材制造用球形粉末时,应选择4.0 MPa的气雾化压力并选择环缝喷嘴,方能得到质量最佳的球形粉末。

关键词：增材制造球形粉末真空气雾化法工艺参数 AlSi10Mg合金