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Visualization of atomic scale reaction dynamics of supported nanocatalysts during oxidation and ammonia synthesis using in-situ environmental(scanning) transmission electron microscopy

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Journal of Energy Chemistry 2021年第6期30卷 281-290,I0007页

作者： Michael r.ward robert W.Mitchell Edward D.Boyes Pratibha L.Gai The York Nanocentre University of YorkYork YO105DDUK Department of Physics University of YorkYork YO105DDUK Department of Electronic Engineering University of YorkYork YO105DDUK Department of Chemistry University of YorkYork YO105DDUK

reaction dynamics in gases at operating temperatures at the atomic level are the basis of heterogeneous gas-solid catalyst reactions and are crucial to the catalyst *** noble metal nanocatalysts such as platinum are of interest in fuel cells and as diesel oxidation catalysts for pollution control,and practical ruthenium nanocatalysts are explored for ammonia *** and graphitic carbons are of interest as supports for the *** considerable literature on the catalytic processes on graphite and graphitic supports,reaction dynamics of the nanocatalysts on the supports in different reactive gas environments and operating temperatures at the single atom level are not well *** we present real time in-situ observations and analyses of reaction dynamics of Pt in oxidation,and practical ru nanocatalysts in ammonia synthesis,on graphite and related supports under controlled reaction environments using a novel in-situ environmental(scanning) transmission electron microscope with single atom *** recording snapshots of the reaction dynamics,the behaviour of the catalysts is *** images reveal single metal atoms,clusters of a few atoms on the graphitic supports and the support *** all play key roles in the mobility,sintering and growth of the *** experimental findings provide new structural insights into atomic scale reaction dynamics,morphology and stability of the nanocatalysts.

关键词： In-situ visualization Atomic scale reaction dynamics In-situ environmental scanning transmission electron microscopy with single atom resolution Supported nanoparticles Ammonia synthesis Oxidation reactions

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Performance of silver nanoparticles in the catalysis of the oxygen reduction reaction in neutral media： Efficiency limitation due to hydrogen peroxide escape

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Nano research 2013年第7期6卷 511-524页

作者： Christopher C. M. Neumann Eduardo Laborda Kristina Tschulik Kristopher r. ward richard G. Compton Department of Chemistry Physical and Theoretical Chemistry Laboratory Oxford University South Parks Road Oxford OXl 3QZUnited Kingdom

The electrocatalytic activity for oxygen reduction reaction （Orr） at neutral pH of citrate-capped silver nanoparticles （diameter = 18 nm） supported on glassy carbon （GC） is investigated voltammetrically. Novelly, the modification of the substrate by nanoparticles sticking to form a random nanoparticle array and the voltammetric experiments are carried out simultaneously by immersion of the GC electrode in an air-saturated 0.1 M NaC104 solution （pH = 5.8） containing chemically-synthesized nanoparticles. The experimental voltammograms of the resulting nanoparticle array are simulated with homemade programs according to the two-proton, two-electron reduction of oxygen to hydrogen peroxide where the first electron transfer is rate determining. In the case of silver electrodes, the hydrogen peroxide generated is partially further reduced to water via heterogeneous decomposition. Comparison of the results obtained on a silver macroelectrode and silver nanoparticles indicates that, for the silver nanoparticles and particle coverages （0.035%-0.457%） employed in this study, the Orr electrode kinetics is slower and the production of hydrogen peroxide larger on the glassy carbon-supported nanoparticles than on bulk silver.

关键词： oxygen reduction reaction silver nanoparticles nanoelectrocatalysis hydrogen peroxide escape fuel cells

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Food supply and the obesity scourge: Is there a relationship?

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Health 2012年第12期4卷 1457-1463页

作者： Lillian Mwanri Wendy Foley John Coveney robert Muller Fiona Verity Paul r. ward Patricia Carter Philip Mohr Anne Taylor Department of Social Work Flinders University Adelaide Australia Discipline of Public Health Flinders University Adelaide Australia Health Promotion Branch SA Health Adelaide Australia Inala Indigenous Health Service Queensland Health Inala Australia Population research and Outcome Studies Unit SA Health Adelaide Australia School of Psychology University of Adelaide Adelaide Australia

This paper reviews literature on the relationship between food supply and obesity. The focus is on the supply, cost, and variety of food through various types of food outlets and the impact of these factors on obesity in developed countries. The article reveals complex relationships between food supply factors and obesity. A numer of factors related to lifestyles including the mobility of populations and the use of motor vehicles greatly reduce the impact of the local environment on family and individual eating patterns. However, obesity is also affected by factors such as the type and density of food outlets, the cost of food, the travel distance and means of transport to the food outlet. While the relationship between food supply and obesity in the literature reveals complex and mixed findings, this paper concludes obesity is complex and food supply is only part of this phenomenon’s predictors. Because the relationship between food supply and obesity is mediated by such multiple and complex factors including population behaviours, beliefs, lifestyles, knowledge and both food and physical environments;multiple strategies including policy development and other strategies aimed at manipulating food environments, physical environments, populations’ beliefs, behaviours and practices must be considered in searching for evidence to effectively combat obesity.

关键词： Obesity Food Supply Food Outlets Socio Economic Status Complex relationships

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A framework for dynamic modelling of railway track switches considering the switch blades,actuators and control systems

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railway Engineering Science 2024年第2期32卷 162-176页

作者： Saikat Dutta Tim Harrison Christopher ward roger Dixon Phil Winship Institute of Thermofluids School of Mechanical EngineeringUniversity of LeedsLeedsWest YorkshireUK Wolfson School of Mechanical Electrical and Manufacturing EngineeringLoughborough UniversityLoughboroughLeicestershireUK Birmingham Centre for railway research and Education School of EngineeringUniversity of BirminghamBirminghamWest MidlandsUK Network rail Milton KeynesBuckinghamshireUK

The main contribution of this paper is the development and demonstration of a novel methodology that can be followed to develop a simulation twin of a railway track switch system to test the functionality in a digital *** is important because,globally,railway track switches are used to allow trains to change routes;they are a key part of all railway ***,because track switches are single points of failure and safety-critical,their inability to operate correctly can cause significant delays and concomitant *** order to better understand the dynamic behaviour of switches during operation,this paper has developed a full simulation twin of a complete track switch *** approach fuses finite element for the rail bending and motion,with physics-based models of the electromechanical actuator system and the control ***,it provides researchers and engineers the opportunity to explore and understand the design space around the dynamic operation of new switches and switch machines before they are *** is useful for looking at the modification or monitoring of existing switches,and it becomes even more important when new switch concepts are being considered and *** simulation is capable of running in real time or faster meaning designs can be iterated and checked *** paper describes the modelling approach,demonstrates the methodology by developing the system model for a novel“rEPOINT”switch system,and evaluates the system level performance against the dynamic performance requirements for the *** the context of that case study,it is found that the proposed new actuation system as designed can meet(and exceed)the system performance requirements,and that the fault tolerance built into the actuation ensures continued operation after a single actuator failure.

关键词： railway track switch Mathematical modelling redundant actuation Finite element analysis

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A flexible,thin-film microchannel electrode array device for selective subdiaphragmatic vagus nerve recording

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Microsystems & Nanoengineering 2024年第1期10卷 115-128页

作者： Jongcheon Lim Peter A.Zoss Terry L.Powley Hyowon Lee Matthew P.ward Weldon School of Biomedical Engineering Purdue UniversityWest LafayetteINUSA Birck Nanotechnology Center Purdue UniversityWest LafayetteINUSA Center for Implantable Devices Purdue UniversityWest LafayetteINUSA Department of Psychological Sciences Purdue UniversityWest LafayetteINUSA Purdue Institute of Integrative Neuroscience Purdue UniversityWest LafayetteINUSA Indiana University School of Medicine IndianapolisINUSA

The vagus nerve(VN)plays an important role in regulating physiological conditions in the gastrointestinal(GI)tract by communicating via the parasympathetic pathway to the enteric nervous system(ENS).However,the lack of knowledge in the neurophysiology of the VN and GI tract limits the development of advanced treatments for autonomic dysfunctions related to the *** better understand the complicated underlying mechanisms of the VN-GI tract neurophysiology,it is necessary to use an advanced device enabled by microfabrication *** several candidates including intraneural probe array and extraneural cuff electrodes,microchannel electrode array devices can be used to interface with smaller numbers of nerve fibers by securing them in the separate channel *** microchannel electrode array devices to interface teased nerve structures are relatively bulky with thickness around 200µ*** thick design can potentially harm the delicate tissue structures,including the nerve *** this paper,we present a flexible thin film based microchannel electrode array device(thickness:11.5µm)that can interface with one of the subdiaphragmatic nerve branches of the VN in a *** demonstrated recording evoked compound action potentials(ECAP)from a transected nerve ending that has multiple nerve ***,our analysis confirmed that the signals are from C-fibers that are critical in regulating autonomic neurophysiology in the GI tract.

关键词： electrode recording film

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煤型稀有金属矿床:成因类型、赋存状态和利用评价

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煤炭学报 2014年第8期39卷 1707-1715页

作者：代世峰任徳贻周义平 Vladimir VSeredin 李大华张名泉 James C Hower Colin r ward 王西勃赵蕾宋晓林中国矿业大学(北京)煤炭资源与安全开采国家重点实验室北京100083 云南省煤炭地质勘查院云南昆明650218 Institute of Ge-ology of Ore Deposits PetrographyMineralogyand GeochemistryRussian Academy of Sciencesmoscow119017 重庆地质矿产研究院重庆400042 University of Kentucky Center for Applied Energy research School of Biological Earth and Environ-mental SciencesUniversity of New South Wales

煤和含煤岩系中稀有金属元素的研究,是当今煤地质学研究的热点问题之一。煤和含煤岩系中高度富集并可以开发利用的稀有金属元素包括锂、钪、钛、钒、镓、锗、硒、锆、铌、铪、钽、铀、稀土元素(包括镧系元素和钇)、贵金属元素等。以煤-... 详细信息

煤和含煤岩系中稀有金属元素的研究,是当今煤地质学研究的热点问题之一。煤和含煤岩系中高度富集并可以开发利用的稀有金属元素包括锂、钪、钛、钒、镓、锗、硒、锆、铌、铪、钽、铀、稀土元素(包括镧系元素和钇)、贵金属元素等。以煤-锗、煤-镓、煤-铀、煤-铌、煤-稀土元素等煤型稀有金属矿床为例,论述了这些矿床的地质成因、赋存状态和利用评价方法。煤型稀有金属矿床的研究,不仅对研究煤层的地质成因、煤层对比、含煤盆地形成与后期改造、区域地质历史演化和突发地质事件可以提供重要的煤地球化学和煤矿物学证据,而且对煤炭经济循环发展、煤炭利用过程中环境保护,以及对国家稀有金属资源安全也具有重要的现实和社会意义。

关键词：煤含煤岩系稀有金属矿床

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墨西哥的医疗保健

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国外医学(卫生经济分册) 1988年第3期 34-37页

作者： ward r 陈静英

引言本文研究墨西哥卫生保健事业的结构及其实施情况,并评价墨西哥主要卫生福利机构在逐步消除卫生保健事业中存在的不平等现象方面取得的成效,并研究首都的医疗保健工作以及近期有关加强基层卫生保健工作的各种倡议对满足公众需求方面... 详细信息

引言本文研究墨西哥卫生保健事业的结构及其实施情况,并评价墨西哥主要卫生福利机构在逐步消除卫生保健事业中存在的不平等现象方面取得的成效,并研究首都的医疗保健工作以及近期有关加强基层卫生保健工作的各种倡议对满足公众需求方面取得多大的成效,另外还将探讨墨西哥是否能实现世界卫生组织提出的“到2000年人人享有医疗保健服务”的战略目标。墨西哥的典型情况是出生率高同时死亡率

关键词：墨西哥居民区收入拉丁美洲财政管理墨西哥城社会保险卫生保健设施人口增加率人口统计人口增长率

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AN/TPN-25和AN/GPN-22精密着陆雷达

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系统工程与电子技术 1981年第7期 37-44页

作者： H.r.ward 宛琰

精密着陆雷达(PAr)用于地面控制进场(GCA)飞机着陆系统,以便飞机最后进入跑道时精确测量其位置。最近为美国空军研制的PAr采用有限扫描相控阵,对着陆飞机进行扫描、搜索和跟踪。本文叙述可机动型和固定场地型PAr以及为鉴定其作用距离和... 详细信息

精密着陆雷达(PAr)用于地面控制进场(GCA)飞机着陆系统,以便飞机最后进入跑道时精确测量其位置。最近为美国空军研制的PAr采用有限扫描相控阵,对着陆飞机进行扫描、搜索和跟踪。本文叙述可机动型和固定场地型PAr以及为鉴定其作用距离和测量精度而进行的机场试验结果。

关键词：雷达仰角方位角传感器出绳角反射器 AN/TPN-25 AN/GPN-22

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rAMP计划中的一次监视雷达——固态监视雷达

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现代雷达 1988年第Z1期 88-93页

作者： H.r.ward 许鸿烈

前言根据雷达现代化计划(rAMP),加拿大所有航管用的一次和二次监视雷达将予更换。新的一次雷达,包括发射机在内,是全固态的,并在信号处理、控制和监视中采用最新的数字技术。为了在发生故障时系统仍能降减性能工作,新雷达用七个独立发... 详细信息

前言根据雷达现代化计划(rAMP),加拿大所有航管用的一次和二次监视雷达将予更换。新的一次雷达,包括发射机在内,是全固态的,并在信号处理、控制和监视中采用最新的数字技术。为了在发生故障时系统仍能降减性能工作,新雷达用七个独立发射机合成射频信号。一个12位的数字动目标检测器(MTD)处理目标回波和气象回波。借助远距离监控分系统,整个雷达能无人值守工作。最近九个月来,根据新方案设计的一个原型样机一直在试验场工作。从其间所得的试验数据中,可以看出雷达的特点和工作性能。

关键词：固态发射机杂波图 rAMP 回波监视雷达距离旁瓣信号处理机频率分集分集接收非线性调频雷达点迹

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The Social Determinants of Food Purchasing Practices: Who Chooses Price-before-Health, Taste-before-Price or Organic Foods in Australia?

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Food and Nutrition Sciences 2012年第4期3卷 461-470页

作者： Paul r. ward Loreen Mamerow Julie Henderson Anne W. Taylor Samantha B. Meyer John Coveney Discipline of Public Health Flinders University Adelaide Australia Population research and Outcome Studies University of Adelaide Adelaide Australia School of Nursing and Midwifery Flinders University Adelaide Australia

A survey of the extent to which cost, taste and health considerations impact food purchasing practices in Australia was conducted. Data were gathered from a national computer assisted telephone survey of 1109 randomly sampled house- holders and analysed using multiple logistic regression analysis. 88% of respondents considered the taste of food before its price, with females and people on higher incomes more likely to do so. 52% of respondents said that they considered the price of food before its health and nutritional benefits, with males, younger people and people with lower educa- tional qualifications more likely to do so. 49% said that they purchase organic food, with people with 1 child, full-time employed and people never married more likely to do so. Overall, gender, income, education, work status, age and family size are all important predictors of food purchasing practices in Australia.

关键词： Food Taste Price Organic Socio-Demographics Survey Logistic regression Australia

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