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Characteristics and Influencing Factors of Microplastics in Snow in the Inner Mongolia Plateau, China

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Engineering 2024年第6期37卷 69-77页

作者： Hongwei Yu Junrong Shao huawei Jia Diga Gang Baiwen Ma Chengzhi Hu State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Changjiang Survey PlanningDesign and Research Co.Ltd.Wuhan 430010China

Microplastics(MPs;<5 mm)have become one of the most prominent global environmental pollution *** can spread to high altitudes through atmospheric transport and can be deposited by rainfall or snowfall,potentially thre... 详细信息

Microplastics(MPs;come one of the most prominent global environmental pollution *** can spread to high altitudes through atmospheric transport and can be deposited by rainfall or snowfall,potentially threatening the structure and function of natural *** in terrestrial and aquatic ecosystems alter the growth and functional characteristics of ***,little attention has been given to the possible harm associated with MPs deposited in snow,particularly in the context of global climate *** collected from surface snow in the Inner Mongolia Plateau,China,were used for quantitative analysis and *** results showed that MPs were easily detected,and the related concentration was approximately(68±10)–(199±2.)MPsL1 in snow *** were the most common morphology,the polymer composition was largely varied,and the abundance and composition of MPs were linked to human activity to a great ***-throughput sequencing results showed that the composition and abundance of microorganisms also differed in snow samples from areas with different MP pollution characteristics,indicating a considerable difference in microbial functional *** may have an interference effect on the individual growth and functional expression of microorganisms in *** addition,the results showed that functional living areas(e.g.,landfills and suburban areas)in cities play an important role in the properties of *** instance,the highest abundance of MPs was found in thermal power plants,whereas the abundance of polymers per sample was significantly lower in the suburban *** MP contaminants hidden in snow can alter microbial structure and function and are therefore a potential threat to ecosystem health.

关键词： Human activities Snow Microplastics Microbial community Urban function Environmental effect

Ce-and La-doped polymetallic layered double hydroxides for enhanced oxygen evolution reaction performance at high current density

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Science China Chemistry 2024年第8期67卷 2586-2598页

作者： Rinel R.Kimaka P. Ping Wang Miao He Senyao Meng Jiasai Yao huawei Li Cheng Yang Zhenxing Li State Key Laboratory of Heavy Oil Processing College of New Energy and MaterialsChina University of Petroleum(Beijing)Beijing 102249China

Polymetallic layered double hydroxides are promising cost-effective catalysts for the oxygen evolution reaction(OER) due to their versatile anionic and cationic tunability. Nevertheless, several challenges persist, notably, issues related to low electrical conductivity, poor catalytic activity, and stability, especially at high current density. Herein, we report the design of Ce-and Ladoped co Ni Fe-layered double hydroxide(Ce La co Ni Fe-LDH) nanosheets through a facile and scalable in situ self-assembly strategy that displays enhanced OER activity. Experimental and theoretical investigations provide insights into the impact of Ceand La-doping by comparing Ce co Ni Fe-LDH, La co Ni Fe-LDH, and pristine co Ni Fe-LDH, all synthesized using the same methodology. These results reveal that doping Ce^(3+)and La^(3+)into co Ni Fe-LDH substantially improves its electronic structure,resulting in enhanced conductivity, more oxygen vacancies(Vo), electron interaction, and active site formation. consequently,significantly reduced overpotentials of 175, 314, and 42. m V at 10, 100, and 500 m A cm^(-2., respectively, and a highly stable current density of 12. h in 1 M KOH were achieved. Notably, these performance metrics surpass those of unmodified LDHs and are competitive with many lanthanide-doped transition metal-based LDH electrocatalysts, as well as noble metal catalysts like ruthenium catalysts. This work represents a pioneering effort in doping Ce^(3+)and La^(3+)ions into a functional co Ni Fe-based electrocatalyst, offering inspiring OER performance and scalability potential.

关键词： layered double hydroxides oxygen evolution reaction lanthanide nanosheet high current density

MoO_(x) nanoclusters on Mo-doped TiO_(2. nanosheets with enhanced singlet oxygen generation and sulfide conversion abilities for photocatalytic aerobic oxidative desulfurization

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Science China Chemistry 2024年第1期67卷 408-414页

作者： Suting Xie Xinyu Zhao Dongxiao Wang huawei Yang Lixia Yang Liangjiu Bai Donglei Wei Wenxiang Wang Ying Liang Hou Chen Shaojun Guo college of Chemistry and Materials Science Ludong UniversityYantai 264025China college of Materials Science and Engineering Peking UniversityBeijing 100871China

Photocatalytic aerobic oxidation desulfurization(PAODS)is a promising and sustainable alternative to conventional,energyintensive desulfurization techniques for petroleum ***,its development is greatly plagued by the low capability in generating highly reactive oxygen species and sluggish kinetics of sulfide oxidation of reported *** we report a class of MoO_(x)nanocluster decorated on ultrathin Mo-doped TiO_(2.nanosheet(MoO_(x)/MoTiO)catalyst for efficiently facilitating the photocatalytic aerobic oxidation of *** demonstrate that MoO_(x)/MoTiO can not only promote the generation of highly reactive singlet oxygen(^(1)O_(2.)but also enhance the aerobic conversion of sulfides,which leads to a record dibenzothiophene oxidation activity of 3.90 mmol g^(-1)h^(-1).The multiple experimental characterizations and density functional theory calculations collectively reveal that the doped-Mo sites can interact with the photogenerated excitons,enabling directly energy transfer generation of^(1)O_(2.through a new exciton modulation mechanism,and the coordination unsaturated MoO_(x)clusters play the role of co-catalyst to enhance the separation of charge carriers,and effectively catalyze the reaction between sulfides and1O_(2.to form sulfones.

关键词： titanium dioxide photocatalytic aerobic oxidation desulfurization dibenzothiophene singlet oxygen

Layer-by-layer epitaxy growth of thickness-controllable two-dimensional tungsten disulfide

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Science China(Information Sciences) 2024年第5期67卷 302-310页

作者： Jieyuan LIANG Zixing ZOU Junwu LIANG Di WANG Biao WANG Anshi CHU Jiali YI Cheng ZHANG Lizhen FANG Tian ZHANG huawei LIU Xiaoli ZHU Dong LI Anlian PAN Key Laboratory for Micro-Nano Physics and Technology of Hunan Province State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan Institute of Optoelectronic IntegrationCollege of Materials Science and Engineering School of Physics and ElectronicsHunan University School of Electronic Information and Electrical Engineering Changsha University School of Physics and Telecommunication Engineering Yulin Normal University Units Semiconductor Technology co. Ltd. School of Physics and Electronics Hunan Normal University

Bilayer transition metal dichalcogenides（TMDs） balance the high mobility of single layers with the high state density of multilayers and therefore have promising application prospects in high-performance electronics. However, the layer-controlled growth of 2. materials is still confronted with challenges such as poor repeatability between different labs and a limited understanding of the growth mechanism at the atomic scale. Herein, we report a new carbon-assisted chemical vapor deposition process that can realize the growth of WS2.heets with high yield, precise thickness controllability, and repeatability. We show that carbon can act as a reducing agent and catalyst that preferentially reacts with the WO3precursor to form intermediate WO3-xproducts with low-valence state W. The resulting oxycarbide gas has a low surface adsorption energy when deposited on the surface of as-grown WS2. which provides nucleation sites for the subsequent layer of WS2.rowth and leads to the vertical growth of WS2.heets. The growth mechanism is thoroughly investigated. Electrical transport measurements show that the produced bilayer WS2.ossesses a high carrier mobility(up to 58 cm2.V-1·s-1) and small subthreshold swing（estimated to be 148 mV/decade）,which are among the best reported results for TMDs produced using CVD.

关键词： WS$_2. thickness-controlled growth chemical vapor deposition additive carbon

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UA5000构筑可信赖的接入网络

世界电信 2006年第11期19卷 72-73页

作者： contributed by huawei Technologies {2. 华为技术有限公司

在市场需求和业务需求的双重驱动下,国内外各电信运营商已经在不同程度上实施了NGN网络的建设和规划,'NGN成为下一代网络发展的必然'已经成为不争的事实.

关键词：接入网络 NGN网络电信运营商下一代网络业务需求国内外驱动

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网络暴力治理:平台责任与守门人角色

交大法学 2024年第3期 51-64页

作者：王华伟北京大学法学院

网络暴力不仅侵害个人法益,而且破坏健康的网络生态。网络暴力概念的失焦,群体聚合作用下个体责任的模糊,表达自由与网络监管的平衡需要,使得网络暴力的治理面临诸多困难。在网络暴力多元共治的基本前提下,除了个体责任的认定之外,应当... 详细信息

网络暴力不仅侵害个人法益,而且破坏健康的网络生态。网络暴力概念的失焦,群体聚合作用下个体责任的模糊,表达自由与网络监管的平衡需要,使得网络暴力的治理面临诸多困难。在网络暴力多元共治的基本前提下,除了个体责任的认定之外,应当重视对网络平台的法律规制。不论是从网络技术和传播学的原理还是从法律责任认定的角度,这都是合理的选择。在当下网络空间违法信息与内容的治理中,突出大型网络平台的守门人角色,已经成为国外代表性法案的做法,这也是我国网络暴力规制的重要制度设计方案。网络平台守门人角色的法理内涵,可以从技术措施和义务承担两个角度来具体展开。网络平台守门人制度应当符合我国网络监管模式的国情,重视民法、行政法、刑法等不同部门法的不同规范目标追求,为其合理构建层级性差异,并通过明确可操作的具体规定来落实。

关键词：网络暴力平台责任守门人层级构造

Predicting the behavior of large scale P2. systems by parallel discrete event simulation

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Science China(Information Sciences) 2010年第6期53卷 1109-1121页

作者： ZHENG WeiMin1,YU HongLiang1,SHI GuangYu2.& CHEN Jian2.1Department of computer Science and Technology,Tsinghua University,Beijing 100084,China 2.0} Technologies co.,ltd,Shenzhen 51812.,China Department of computer Science and Technology Tsinghua University Beijing China huawei Technologies co. Ltd Shenzhen China

P2. systems are becoming the dominator of *** systems are typically composed of thousands to millions of physical computers,which make it difficult to predict their behaviors without a large scale distributed system *** paper is an attempt to predict the behavior of large scale P2. systems by building a novel parallel simulator:AegeanSim,which provides parallel discrete event simulation of such systems on high performance server *** abstract the execution of P2. applications with a specific event model,and parallel the simulation of events in a cluster,thus expanding the simulation scale and boosting the simulation process dramatically.A 1-stage synchronization method is proposed to improve the *** event callback interface is designed to implement their application logic easily while keeping the simulator *** use AegeanSim to predict the behavior of a typical P2. system:*** comparing the simulation behavior of BT with that of related BT studies and verifying its efficiency,scalability and accuracy,we make predictions about the behavior of BT system assuming they are assaulted by different man-made system *** reasonable results are found:(1) Tracker isolation can hardly work because of its short attacking time window.(2. Limiting the bandwidth of BT may be an efficient way to control it.

关键词： P2. simulation parallel

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不同布置形式平单轴光伏支架颤振性能研究

湖南大学学报（自然科学版） 2024年第5期51卷 106-113页

作者：牛华伟陈权姜东李红星湖南大学土木工程学院湖南长沙410082 中国电力工程顾问集团西北电力设计院有限公司陕西西安710075

对1V和2.两类不同布置形式平单轴光伏支架开展缩尺比为1/6的弹性悬挂节段模型测振风洞试验,研究了倾角(-60°~60°)、阻尼水平和光伏组件之间有无间隙对结构颤振性能的影响.结果表明:1V在-30°~30°倾角下发生明显的扭转颤振,2.在±10... 详细信息

对1V和2.两类不同布置形式平单轴光伏支架开展缩尺比为1/6的弹性悬挂节段模型测振风洞试验,研究了倾角(-60°~60°)、阻尼水平和光伏组件之间有无间隙对结构颤振性能的影响.结果表明:1V在-30°~30°倾角下发生明显的扭转颤振,2.在±10°、±2.°和±30°时发生明显的扭转颤振;对于两类支架,结构颤振临界无量纲风速随倾角绝对值的增大先减小后增大,最大差值超过3.87倍(1V)和2.45倍(2.),且相同工况下,负倾角颤振性能优于正倾角;建议选择0°作为结构大风保护角度;1V和2.结构颤振性能随阻尼比的增大而提升,但和2.相比1V颤振性能提升对于阻尼比更不敏感;光伏组件之间的间隙对结构颤振性能基本无影响.

关键词：平单轴光伏支架风洞试验颤振倾角阻尼比间隙

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HONET在数据通信中的应用

世界电信 1998年第5期11卷 21-22页

作者： contributed by huawei Technologies co, {2.. 深圳市华为技术有限公司

由于经济条件的限制,我国DDN用户节点侧一直发展缓慢,用户使用很不灵活。华为HONET综合业务接入网的开发思路是为满足用户实际需求,除接入公用电话网提供电话、传真等多种业务外,还可作为DDN的接入设备,实现DDN的延伸,为用户提供数字数... 详细信息

由于经济条件的限制,我国DDN用户节点侧一直发展缓慢,用户使用很不灵活。华为HONET综合业务接入网的开发思路是为满足用户实际需求,除接入公用电话网提供电话、传真等多种业务外,还可作为DDN的接入设备,实现DDN的延伸,为用户提供数字数据接入和系统内部的各种速率接口的数据专线业务。

关键词：数字数据网数字接口接入网数据速率