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Highly selective growth of(6,5)single-walled carbon nanotubes from sigma phase alloy catalyst

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nano Research 2024年第3期17卷 1999-2003页

作者： liantao Xin Chen Ma Qianru Wu Shaokang liu linhai li Xiuyun Zhang liu Qian Maoshuai He Dong li Fangqian Han Shulan Hao lihu Feng Yahan li Huaping liu lili Zhang Chang liu Jin Zhang College of Chemistry and Molecular Engineering Qingdao University of Science and TechnologyQingdao 266042China Shenyang national Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Beijing national Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China College of Physics Science and Technology Yangzhou UniversityYangzhou 225002China Center for nanochemistry Beijing Science and Engineering Center for NanocarbonsBeijing National Laboratory for Molecular SciencesCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

The chirality structure of a single-walled carbon nanotube(SWNT)strongly depends on the composition of catalyst used in the chemical vapor deposition *** this study,we develop a porous magnesia supported manganese-rhenium(MnRe/MgO)catalyst for chirality-selective synthesis of *** characterizations reveal that(6,5)tubes with a selectivity higher than 70%are grown from the Re-rich MnRe/MgO *** comparing the SWNT growth results with those of monometallic Mn or Re,the formation of sigma phase,an intermetallic compound occurring in transition-metal alloy systems,is revealed to be crucial for the dominant synthesis of(6,5)*** work not only extends the application of sigma phase alloy for catalytic synthesis of SWNTs,but also sheds lights on the growth of SWNTs with a high chirality selectivity.

关键词： single-walled carbon nanotubes sigma phase manganese-rhenium catalyst selective growth transition-metal alloy

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果蔬采后分级和预冷车辆协同调度模型与算法

系统管理学报 2024年第1期33卷 76-89页

作者：王旭坪王悦李娅林娜海南科技职业大学财经学院海南海口571126 大连理工大学智慧商务物流研究所辽宁大连116024

新兴的移动式分级、预冷技术应用于果蔬田间采后处理,有助于降低采后损耗,也催生了采后“最先一公里”冷链物流环节协同运作优化问题。以采后分级、预冷环节为例,综合考虑果蔬最佳预冷时间、先分级后预冷的服务顺序等特有协同情景,构建... 详细信息

新兴的移动式分级、预冷技术应用于果蔬田间采后处理,有助于降低采后损耗,也催生了采后“最先一公里”冷链物流环节协同运作优化问题。以采后分级、预冷环节为例,综合考虑果蔬最佳预冷时间、先分级后预冷的服务顺序等特有协同情景,构建了移动式分级预冷资源协同调度优化模型。与现有模型不同,本研究考虑延迟预冷对果蔬新鲜度的特殊影响,设计了延迟预冷成本函数,在保障产品质量的同时最小化服务运作成本。设计混合遗传算法对模型进行求解,该算法融合了遗传算法与邻域搜索算法,增强混合算法的局部和全局搜索能力。其中,结合问题的双需求特点及关键协同约束,设计了基于双序列的解的表达方式、基于最佳插入策略的交叉算子以及基于三阶段邻域搜索的变异操作,以提高算法的收敛速度与求解质量。通过与标准遗传算法和变邻域搜索算法对比,验证了本文算法在求解大规模算例时可以更快收敛到更高质量的解。基于陕西省洛川县水蜜桃产业的分级预冷数据证明了模型的合理性。本研究有助于把协同运作优化思想引入果蔬采后“最先一公里”冷链物流环节,为降低我国果蔬采后损耗提供创新性解决思路。

关键词：最先一公里移动式分级和预冷协同调度混合遗传算法邻域搜索

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HFE-7100平行微通道流动沸腾实验

物理学报 2024年第5期73卷 178-189页

作者：解奕晨庄晓如岳思君李翔余鹏鲁春南方科技大学力学与航空航天工程系深圳518055 深圳职业技术大学机电工程学院深圳518055

微通道流动沸腾冷却技术兼具相变潜热和微尺度效应的诸多优点,是解决微电子器件热致失效问题的重要方法之一.HFE-7100是一种安全环保的电子氟化液,特别适用于微电子器件的冷却.本文在水力直径为0.5 mm的矩形平行微通道内,对HFE-7100的... 详细信息

微通道流动沸腾冷却技术兼具相变潜热和微尺度效应的诸多优点,是解决微电子器件热致失效问题的重要方法之一.HFE-7100是一种安全环保的电子氟化液,特别适用于微电子器件的冷却.本文在水力直径为0.5 mm的矩形平行微通道内,对HFE-7100的流动沸腾传热和两相流动特性进行了实验研究,测量范围为常压下质量流率88.9-277.8 kg·m^(-2)·s^(-1)、入口过冷度20.5-35.5℃和有效热流密度12-279 kW·m^(-2).本文分析了质量流率、入口过冷度、有效热流密度和干度对传热系数和压降的影响,发现在较低的入口过冷度下HFE-7100出现了沸腾迟滞现象,且增大入口过冷度和质量流率会延缓沸腾起始点的发生,且会提高传热系数和临界热流密度.两相压降受有效热流密度影响较大,且在定干度下不同质量流率的两相压降在塞状流和环状流阶段有明显差异.同时,通过观测两相流型,对流动沸腾传热现象进行了分析.本文还将两相压降实验数据与文献关联式预测值进行了对比,与Lockhart提出的关联式预测值偏差为19.6%.本文研究结果可为微电子器件散热设备的优化设计提供理论指导:以HFE-7100作为传热工质并将微通道流动沸腾冷却技术应用于微电子器件散热设备,可以提高设备的稳定性和可靠性;在不同热流密度的设备中通过控制入口过冷度和质量流率可有效地提升其散热性能;采用Lockhart提出的两相压降关联式可预测散热设备所需的泵功.

关键词：流动沸腾微通道 HFE-7100 传热电子器件

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Unveiling the critical role of TiO_(2)-supported atomically dispersed Cu species for enhanced photofixation of N_(2)to nitrate

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Fundamental Research 2024年第4期4卷 934-940页

作者： Dong li Yunxuan Zhao Chao Zhou li-Ping Zhang Junwang Tang Tierui Zhang Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBejing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBejing 100049China School of Future Technology University of Chinese Academy of SciencesBejing 100049China Department of Chemical Engineering University College LondonLondon WC1E7JEUnited Kingdom

Nitrate products are widely used in manufacturing as crucial raw materials and *** traditional nitrate synthesis process involves high energy consumption and emission,thereby opposing the goals of zero-carbon emission and green ***,a sustainable roadmap for nitrate synthesis that uses green energy input,clean N sources,and direct catalytic processes is urgently required(e.g.,developing a novel photosynthesis system).Here,we synthesized TiO2-supported atomically dispersed Cu species for N_(2)photofixation to nitrate in a flow *** optimized photocatalyst yielded a high nitrate photosynthesis rate of 0.93μmol h-1 and selectivity of~90%,which is superior to most of the values reported thus ***,experimental results and in-situ investigations revealed that the atomically dispersed Cu sites in the as-designed sample significantly enhanced the separation and transfer efficiency of photogenerated carriers,adsorption and activation of reactants,and the formation of chemisorbed O_(x)intermediates,thereby realizing the excellent photofixation of N_(2)to nitrate.

关键词： N_(2) photofixation TiO_(2) Nitrate photosynthesis Cu species NO_(x),intermediates

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长江流域城市绿色发展评价与障碍影响

生态学报 2024年第15期44卷 6554-6566页

作者：李林子邓陈宁詹丽雯李小敏谢明辉中国环境科学研究院环境基准与风险评估国家重点实验室北京100012

建设长江流域绿色发展示范带是美丽中国建设的重大任务,开展城市绿色发展评估和障碍影响识别有助于推动长江流域绿色发展。构建了以水为纽带、体现“三水”统筹的长江流域城市绿色发展指标体系,基于CRITIC-熵权、TOPSIS、障碍度模型和... 详细信息

建设长江流域绿色发展示范带是美丽中国建设的重大任务,开展城市绿色发展评估和障碍影响识别有助于推动长江流域绿色发展。构建了以水为纽带、体现“三水”统筹的长江流域城市绿色发展指标体系,基于CRITIC-熵权、TOPSIS、障碍度模型和系统聚类等综合评价方法,对流域内63个重点城市2012—2021年的绿色发展和障碍影响进行评估。结果表明:(1)共抓大保护以来长江流域城市绿色发展进程明显加快;(2)经济规模、生产率、环境效率对城市绿色发展的阻碍明显减小,产业结构重化工化、农业面源污染的阻碍更加突显,多数城市绿色发展都面临水资源开发程度高和经济社会用水效率低的障碍;(3)生态阻力型城市应重点加强水生态环境安全管理,降低资源开发强度,执行更严格的管控制度;经济阻力型城市应重点发展零污染产业,建立健全生态产品价值实现机制;效率阻力型城市应强化水资源刚性约束,推动工农业生态循环发展,大幅提高资源环境效率;生态-经济阻力型城市应率先推动涉水产业绿色改造和优化升级,提升市场竞争优势,同时加强涉水产业环境风险管理;混合阻力型城市应重点依靠创新驱动推动产业转型升级和资源环境效率提升,同时统筹好“三水”关系。

关键词： CRITIC-熵权 TOPSIS 障碍度绿色发展长江

Utilizing EMR Data for Smoking Behavior Surveillance in Hospitalized Patients With Chronic Respiratory Diseases and Its Impact on Clinical Outcomes—Beijing Municipality,China,2014–2023

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China CDC weekly 2024年第22期6卷 530-534页

作者： Jiachen li Jian Su Zhaohui Tong lirong liang Department of Clinical Epidemiology Beijing Institute of Respiratory Medicine and Beijing Chao-Yang HospitalCapital Medical UniversityBeijingChina School of Economics Peking UniversityBeijingChina Department of Respiratory and Critical Care Medicine Beijing Institute of Respiratory Medicine and Beijing Chao-Yang HospitalCapital Medical UniversityBeijingChina

What is already known on this topic?Smoking is the primary risk factor for a poor prognosis in chronic respiratory disease(CRD).Current tobacco surveillance efforts in China focus on the general population and do not adequately cover CRD *** is added by this report?We employed electronic medical records(EMR)to track smoking habits in 28,334 hospitalized CRD patients at Beijing Chao-Yang *** rates of former and current smokers were 30.7%and 18.0%,*** former and current smokers exhibited an increased risk of respiratory symptoms and extended hospital *** are the implications for public health practice?These results underscore the importance of implementing smoking monitoring and targeted cessation interventions for hospitalized patients with CRDs.

关键词： respiratory prognosis smoke

Selective dissolution for stabilizing solid electrolyte interphase

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Chinese Chemical Letters 2024年第5期35卷 1-2页

作者： Kezhen Qi Shu-yuan liu Ruchun li College of Pharmacy Dali UniversityDali 671000China Faculty of Chemistry and Chemical Engineering Yunnan Normal UniversityKunming 650500China

With pursuing high energy density batteries,traditional graphite anode could be unable to meet current needs[1-4].The high-capacity anodes have attracted increasing attention,such as lithium anodes and alloy-type anodes[5-8].Silicon anode,as a high-capacity alloy-type anode(3579 mAh/g),has attracted great attention[9].However,due to its unique electrochemical mechanism,significant changes in volume and morphology during charge/discharge process could lead to the decrease in cycling stability[9,10].Therefore,it is still challenging for silicon anode in tackling volume expansion and unstable interfaces.

关键词： electrolyte cycling unstable

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烟台市奶农种养加一体化发展情况分析

中国乳业 2024年第8期 74-77页

作者：孙艳谢凯秦娜烟台市农业技术推广中心山东烟台264001 招远市蚕庄畜牧兽医站山东烟台265400 招远市金岭畜牧兽医站山东烟台265404

种养加一体化是奶业未来发展趋势。本文从种植、养殖、加工3个层面入手,调查烟台市饲草种植、奶牛养殖、乳品加工情况,报告烟台市种养、养加及种养加一体化发展现状,探讨土地资源紧张、资金筹措难、销售渠道不健全等问题,提出破解对策,... 详细信息

种养加一体化是奶业未来发展趋势。本文从种植、养殖、加工3个层面入手,调查烟台市饲草种植、奶牛养殖、乳品加工情况,报告烟台市种养、养加及种养加一体化发展现状,探讨土地资源紧张、资金筹措难、销售渠道不健全等问题,提出破解对策,为烟台市奶业高质量发展提供可行思路。

关键词：饲草种植奶牛养殖乳品加工一体化发展

Analytical evaluation of steady-state solute distribution in through- diffusion and membrane behavior test under non-perfectly flushing boundary conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 258-267页

作者： Guannian Chen Yuchao li Kristin MSample-Lord Shan Tong School of Civil&Environmental Engineering and Geography Science Ningbo UniversityNingbo315211China MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou310058China Ningbo ZCONE High-tech Company limited Ningbo315000China Department of Civil and Environmental Engineering Villanova UniversityVillanovaPAUSA

The through-diffusion and membrane behavior testing procedure using a closed-system apparatus has been widely used for concurrent measurement of diffusion and membrane efficiency coefficients of low-permeability clay-based barrier ***,the common assumption of perfectly flushing conditions at the specimen boundaries could induce errors in analyses of the diffusion coefficients and membrane *** this study,an innovative pseudo three-dimensional(3D)analytical method was proposed to evaluate solute distribution along the boundary surfaces of the soil-porous disks system,considering the non-perfectly flushing *** results were consistent with numerical models under two scenarios considering different inflow/outflow *** proposed model has been demonstrated to be an accurate and reliable method to estimate solute distributions along the *** calculated membrane efficiency coefficient and diffusion coefficient based on the proposed analytical method are more accurate,resulting in up to 50%less relative error than the traditional approach that adopts the arithmetic mean value of the influent and effluent *** retar-dation factor of the clay specimen also can be calculated with a revised cumulative mass ***,the simulated transient solute transport matched with experimental data from a multi-stage through-diffusion and membrane behavior test,validating the accuracy of the proposed method.

关键词： Diffusion testing Membrane behavior Coupled transport Clay barrier Transport modeling