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Interfacial Structures Governed Plastic Deformation Behaviors in Metallic Multilayers

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Acta Metallurgica Sinica(English Letters) 2016年第2期29卷 199-204页

作者： Ming-Zhen Wei Zhen-Hua Cao Xiang-kang meng Institute of Materials Engineering National Laboratory of Solid State Microstructures College of Engineering and Applied Sciences Nanjing University Department of Physics School of Science Linyi University

In this work, we have investigated the mechanical properties of Cu/Ta, Ag/Cu and Ag/Nb multilayers with different heterogeneous interfaces. The results suggest that when individual layer thickness （h） is larger than 5-10 nm, the hardness/strength of three different multilayer systems has the similar length scale effect with decreasing layer thickness, while when h ≤ 5 nm, the three multilayer systems show remarkably different plastic deformation behaviors. The strength curves exhibit the variation trends of unchanging, softening and increasing corresponding to Cu/Ta, Ag/Cu and Ag/Nb multilayers, respectively. The microstructure analysis shows that three kinds of multilayers have totally different interfacial structures, which lead to the different strengthening or softening mechanisms.

关键词： Metallic multilayers Plastic deformation Interfacial structures Strengthening mechanism

Numerical simulation of gas-liquid two-phase flow impacting fixed structure by CLSVOF/IB method based on OpenFOAM

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Journal of Hydrodynamics 2021年第6期33卷 1176-1189页

作者： Wen-kang meng Ching-hao Yu Jia Li Rui-dong An State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China

In this paper,a coupled level set and volume of fluid,immersed boundary(CLSVOF/IB)method is proposed and implemented into the interFoam solver of the OpenFOAM to simulate the gas-liquid two-phase flows,involving the gas-liquid and fluid-structure *** the volume of fluid(VOF)method,the multidimensional universal limiter with explicit solution(MULES)approach is used to restrain the volume *** approach for calculating the grid characteristic size for the level set(LS)initial function and the re-initialization equation is proposed in order to make it more applicable to non-uniform grids in the finite volume *** the proposed CLSVOF method,the continuous LS function is used to calculate the gas-liquid interface curvature so that the surface tension term can be calculated *** the immersed boundary(IB)method proposed in this paper,a virtual forcing term is introduced in the momentum equation to deal with the fluid-structure interface by defining a solid volume fraction,which is convenient for the three-dimensional numerical *** the present flow field solver,an improved scheme of the velocity predictor loop of the PIMPLE framework is also *** benchmark cases:the Zalesak’s notched disk and a circular bubble at equilibrium,are simulated first to examine the accuracy of the present CLSVOF ***,the effects of several gas-liquid two-phase flows on different fixed structures are *** simulation results are in good agreement with the published numerical and experimental results.

关键词： Volume of fluid(VOF)method level set(LS)method immersed boundary method gas-liquid interface fluid-structure interface

Adaptive Photon Mapping Based on Gradient

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Journal of Computer Science & Technology 2016年第1期31卷 217-224页

作者： Chun-meng kang Lu Wang Yan-Ning Xu Xiang-Xu meng Yuan- Jie Song School of Computer Science and Technology Shandong University Jinan 252000 China Engineering Research Center of Digital Media Technology Ministry of Education Jinan 252000 China

Photon mapping can simulate some special effects efficiently such as shadows and caustics. Photon mapping runs in two phases： the photon map generating phase and the radiance estimation phase. In this paper, we focus on the bandwidth selection process in the second phase, as it can affect the final quality significantly. Poor results with noise arise if few photons are collected, while bias appears if a large number of photons are collected. In order to solve this issue, we propose an adaptive radiance estimation solution to obtain trade-offs between noise and bias by changing the number of neighboring photons and the shape of the collected area according to the radiance gradient. Our approach can be applied in both the direct and the indirect illumination computation. Finally, experimental results show that our approach can produce smoother quality while keeping the high frequency features perfectly compared with the original photon mapping algorithm.

关键词： photo-realistic rendering global illumination photon mapping radiance estimation

良方温经汤调控CHCHD4表达干预寒凝血瘀型子宫内膜异位症乏氧的机制研究

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中国中药杂志 2024年第14期49卷 3818-3827页

作者：邢易果金玉刘鹏郭权磊成秀梅康佳梦任艳青河北中医药大学河北石家庄050091 河北省中药配方颗粒技术创新中心河北石家庄050091 中药材品质评价与标准化河北省工程研究中心河北石家庄050091

探究良方温经汤调控卷曲螺旋卷曲螺旋结构域4(CHCHD4)表达干预寒凝血瘀型子宫内膜异位症(EMs)乏氧环境的机制。冰水浴法制备大鼠寒凝血瘀证模型,在此基础上采用自体移植法建立EMs模型,随机分为模型组,良方温经汤低、中、高(4.7、9.4、18... 详细信息

探究良方温经汤调控卷曲螺旋卷曲螺旋结构域4(CHCHD4)表达干预寒凝血瘀型子宫内膜异位症(EMs)乏氧环境的机制。冰水浴法制备大鼠寒凝血瘀证模型,在此基础上采用自体移植法建立EMs模型,随机分为模型组,良方温经汤低、中、高(4.7、9.4、18.8 g·kg^(-1))剂量组及少腹逐瘀汤组,另设假手术组,每组10只,灌胃给药4周。造模期间进行大鼠一般情况观察及阴道涂片,并通过激光散斑衬比成像(LSCI)检测耳部及子宫血流,以判断寒凝血瘀证候情况;给药结束后观察大鼠一般情况;卡尺测量异位病灶面积;免疫组织化学法检测CHCHD4、乏氧诱导因子^(-1)α(HIF^(-1)α)的定位与表达;实时定量聚合酶链反应(RT-qPCR)及蛋白免疫印迹检测CHCHD4、HIF^(-1)αmRNA和蛋白的表达。进行EMs患者异位子宫内膜间质细胞(ESCs)原代培养,构建CHCHD4过表达质粒,转染建立CHCHD4过表达ESCs模型。将细胞分为空白对照组、CHCHD4过表达组、CHCHD4过表达+空白血清组、CHCHD4过表达+良方温经汤血清组,蛋白免疫印迹检测CHCHD4、HIF^(-1)α蛋白的表达;并检测葡萄糖消耗量及乳酸水平;MTT法检测细胞增殖情况。结果显示,与正常大鼠相比,造模大鼠出现精神萎靡、饮食饮水减少、动情周期紊乱,耳部及子宫微血管血液循环受阻等寒凝血瘀证候表征。与假手术组相比,模型组大鼠异位病灶隆起,CHCHD4、HIF^(-1)αmRNA及蛋白表达显著升高(P<0.05);与模型组相比,各给药组大鼠寒凝血瘀表征均有改善,异位病灶面积显著缩小(P<0.05或P<0.01),CHCHD4、HIF^(-1)αmRNA与蛋白表达显著降低(P<0.05或P<0.01)。在细胞模型中,与空白对照组相比,CHCHD4过表达组CHCHD4、HIF^(-1)α蛋白表达、葡萄糖消耗量、乳酸水平、细胞增殖活力均显著升高(P<0.01);与CHCHD4过表达组相比,空白血清组各指标均无明显变化,良方温经汤血清组CHCHD4、HIF^(-1)α蛋白表达显著下降(P<0.05或P<0.01),葡萄糖消耗量、乳酸水平显著降低(P<0.01),细胞增殖活力显著下降(P<0.01)。由上可知,良方温经汤对寒凝血瘀型EMs的治疗作用与降低CHCHD4表达,进而改善异位病灶及异位ESCs乏氧有关。

关键词：良方温经汤寒凝血瘀型子宫内膜异位症卷曲螺旋卷曲螺旋结构域4(CHCHD4) 乏氧诱导因子-1α(HIF-1α) 子宫内膜间质细胞

Performance improvement of ultra-low Pt proton exchange membrane fuel cell by catalyst layer structure optimization

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Chinese Journal of Chemical Engineering 2022年第1期35卷 473-479页

作者： Jinyan Xi kang meng Ying Li meng Wang Qiang Liao Zidong Wei Minhua Shao Jianchuan Wang School of Chemistry&Chemical Engineering Chongqing UniversityChongqing 400044China School of Energy and Power Engineering Chongqing UniversityChongqing 400044China School of Chemistry and Bioengineering HongKong University of Science and TechnologyHong KongChina

Reducing the loading of noble Pt-based catalyst is vital for the commercialization of proton exchange membrane fuel cell(PEMFC),However,severe mass transfer polarization loss resulting in fuel cell performance decline will be encountered in ultra-low Pt *** this work,mild oxidized multiwalled carbon nanotubes(mMWCNT)were adopted to construct the catalyst layer,and by varying the loading of carbon nanotubes,the catalyst layer structure was optimized.A high peak power density of 1.23 W·cm^(-2) for the MEA with mMWCNT was obtained at an ultra-low loading of 120μg·cm^(-2) Pt/PtRu(both cathode and anode),which was 44.7%higher than that of MEA without *** catalyst dispersion,low charge transfer resistance,more porous structure and high hydrophobicity of catalyst layer were ascribed for the reasons of the performance improvement.

关键词： Catalyst Mass transfer Optimization Fuel cell Ultra-low platinum Carbon nanotubes

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开拓巷道新型柔性密闭喷涂支护技术实践

陕西煤炭 2024年第2期43卷 99-103页

作者：康萌冯建志曹东升陕西陕煤韩城矿业公司陕西渭南715400

为满足煤矿开拓掘进巷道支护、安全及环保的要求,基于快速薄喷喷涂技术及相关材料技术应用现状,研制了煤岩体表面柔性喷涂材料,即双采(SCPPT-2型)复合喷涂材料。将该材料应用于下峪口煤矿2-2煤层采区边界泄水巷开拓巷道支护,并以该项目... 详细信息

为满足煤矿开拓掘进巷道支护、安全及环保的要求,基于快速薄喷喷涂技术及相关材料技术应用现状,研制了煤岩体表面柔性喷涂材料,即双采(SCPPT-2型)复合喷涂材料。将该材料应用于下峪口煤矿2-2煤层采区边界泄水巷开拓巷道支护,并以该项目的开展为基础,定型了封闭围岩面的非反应型薄喷产品。研究结果及现场应用表明,所研制的薄喷材料成膜质量好,抗拉强度大于2.5 MPa,环保性能达到室内建材标准;薄喷技术与喷射混凝土相比,材料运输量减少90%以上,用人量大大减少,施工速度提高4~6倍,封堵后的巷道内瓦斯溢出明显减少。

关键词：开拓巷道薄喷技术喷涂支护柔性材料巷道支护

新型污染物的环境行为与生态风险评估及防治策略研究

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皮革制作与环保科技 2024年第3期5卷 97-99页

作者：孙翠平康蒙孟凡伟韩子叻山东省生态环境规划研究院山东济南250101 山东高速天鸿产业投资控股有限公司山东济南250101

新型污染物的环境行为与生态风险评估及防治策略研究是一项重要的环境保护工作。该研究旨在深入探究新型污染物在环境中的迁移、转化、降解等行为,评估其对生态环境和人类健康的潜在风险,并提出有效的防治策略。通过对新型污染物的环境... 详细信息

新型污染物的环境行为与生态风险评估及防治策略研究是一项重要的环境保护工作。该研究旨在深入探究新型污染物在环境中的迁移、转化、降解等行为,评估其对生态环境和人类健康的潜在风险,并提出有效的防治策略。通过对新型污染物的环境行为进行深入研究,我们可以更好地了解其在环境中的变化规律,为生态风险评估提供科学依据。同时,通过评估新型污染物的生态风险,我们可以及时发现潜在的环境问题,为采取有效的防治策略提供指导。本研究将为保护生态环境和人类健康提供重要的理论支持和实践指导。

关键词：新型污染物环境行为生态风险评估防治策略环境保护

Research on Distributed Data Sharing System based on Internet of Things and Blockchain

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Journal of Systems Science and Information 2021年第3期9卷 239-254页

作者： Enchang SUN kang meng Ruizhe YANG Yanhua ZHANG meng LI School of Information and Communications Engineering Faculty of InformationBeijing University of TechnologyBeijing 100124China

Aiming at the problems of the traditional centralized data sharing platform,such as poor data privacy protection ability,insufficient scalability of the system and poor interaction ability,this paper proposes a distributed data sharing system architecture based on the Internet of Things and blockchain *** this system,the distributed consensus mechanism of blockchain and the distributed storage technology are employed to manage the access and storage of Internet of Things data in a secure *** to the physical topology of the network,a hierarchical blockchain network architecture is proposed for local network data storage and global network data sharing,which reduces networking complexity and improves the scalability of the *** addition,smart contract and distributed machine learning are adopted to design automatic processing functions for different types of data(public or private)and supervise the data sharing process,improving both the security and interactive ability of the system.

关键词： blockchain smart contract Internet of Things data sharing

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近距离煤层非对称变形巷道支护设计

陕西煤炭 2024年第7期43卷 95-98,122页

作者：孙鹏姬东康萌蔡敏博陕西陕煤韩城矿业有限公司下峪口煤矿陕西渭南715400

在煤层巷道掘进期间,由于近距离煤层开采使得在23306_下进顺初期掘进期间顶板破碎以及两帮的围岩变形严重。对于陕西省陕煤韩城矿业有限公司下峪口煤矿23306_下进顺,在掘进过程中产生的巷道围岩变形以及巷道支护困难等问题,结合现场的... 详细信息

在煤层巷道掘进期间,由于近距离煤层开采使得在23306_下进顺初期掘进期间顶板破碎以及两帮的围岩变形严重。对于陕西省陕煤韩城矿业有限公司下峪口煤矿23306_下进顺,在掘进过程中产生的巷道围岩变形以及巷道支护困难等问题,结合现场的地质条件,采用理论分析、现场监测等方法,探究在掘进期间顶板破碎的原因以及通过优化支护方案来改善巷道的围岩情况。结果表明,改善后采用“锚网索+U型棚”支护的方法,可以有效地改善巷道围岩变形的情况,通过对巷道围岩变形量的进一步观测验证,在巷道顶板容易破碎时选择合理的支护参数,在技术和经济层面上选择采用“锚网索+架棚”支护方式能够保障矿井的安全高效开采。

关键词：巷道围岩变形锚网支护现场监测支护优化