检索结果-南通市图书馆

Transition Metal Aluminum Boride as a New Candidate for Ambient-Condition Electrochemical Ammonia Synthesis

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2020年第5期12卷 106-118页

作者： Yang Fu Peter Richardson Kangkang Li Hai Yu Bing Yu Scott Donne Erich Kisi Tianyi Ma Discipline of Chemistry School of Environmental and Life SciencesUniversity of NewcastleCallaghanNSW 2308Australia School of engineering University of NewcastleCallaghanNSW 2308Australia CSIRO Energy 10 Murray Dwyer CircuitMayfield WestNSW 2304Australia School of Environmental Science and engineering Fujian Normal UniversityFuzhou 350007FujianPeople’s Republic of China

Achieving more meaningful N2 conversion by reducing the energy input and carbon footprint is now being investigated through a method of N2 fixation instead of the Haber-Bosch ***,the electrochemical N2 reduction reaction(NRR)method as a rising approach currently still shows low selectivity(Faradaic efficiency<10%)and high-energy consumption[applied potential at least-0.2 V versus the reversible hydrogen electrode(RHE)].Here,the role of molybdenum aluminum boride single crystals,belonging to a family of ternary transition metal aluminum borides known as MAB phases,is reported for the electrochemical NRR for the first time,at a low applied potential(-0.05 V versus RHE)under ambient conditions and in alkaline *** to the unique nano-laminated crystal structure of the MAB phase,these inexpensive materials have been found to exhibit excellent electrocatalytic performances(NH3 yield:9.2μg h^-1cm^-2mgcat^-1.,Faradaic efficiency:30.1%)at the low overpotential,and to display a high chemical stability and sustained catalytic *** conjunction,further mechanism studies indicate B and Al as main-group metals show a highly selective affinity to N2 due to the strong interaction between the B 2p/Al 3p band and the N 2p orbitals,while Mo exhibits specific catalytic activity toward the subsequent reduction ***,the MAB-phase catalyst under the synergy of the elements within ternary compound can suppress the hydrogen evolution reaction and achieve enhanced NRR *** significance of this work is to provide a promising candidate in the future synthesis of ammonia.

关键词： MAB phase N2 reduction reaction Electrocatalysis Nanostructure

Interpretation of pipe-jacking and lubrication records for drives in silty soil

在线全文

学校读者我要写书评

暂无评论

Underground Space 2020年第3期5卷 199-209页

作者： Kevin G.O’dwyer Bryan A.McCabe Brian B.Sheil Civil engineering College of Engineering and InformaticsNational University of IrelandGalwayIreland Department of engineering Science University of OxfordUnited Kingdom

In recent years,there has been an increased resort to microtunnelling/pipe-jacking as a means of constructing underground conduits(for water,sewage,gas,and other utilities)to avoid on-street disruption in urban *** this paper,technical details of two 1200 mm internal diameter microtunnels in silty sand totalling over 550 m in length are *** average skin friction values are extremely low for both drives suggesting effective lubrication practice,differences in normalised bentonite volumes appear to be responsible for differences in skin *** or near full buoyancy of the pipeline has been demonstrated for the majority of the *** frictional stress increase after a stoppage is shown to depend on not only the stoppage duration but also on the normalised lubrication *** of data in the manner presented in the paper is an important means of assimilating experience of microtunnelling in different ground conditions.

关键词： Microtunnelling Pipe-jacking Skin friction Lubrication Pipe buoyancy Stoppages

Current advancements on charge selective contact interfacial layers and electrodes in flexible hybrid perovskite photovoltaics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2021年第3期30卷 151-173页

作者： Gopalan Saianand Prashant Sonar Gregory J.Wilson Anantha-Iyengar Gopalan Vellaisamy A.L.Roy Gautam E.Unni Khan Mamun Reza Behzad Bahrami K.Venkatramanan Qiquan Qiao Global Centre for Environmental Remediation(CCER) Faculty of ScienceThe University of NewcastleCallaghan 2308New South WalesAustralia CSIRO Energy Newcastle Energy Centre10 Murray Dwyer CctMayfield WestNSW 2304Australia School of Chemistry and Physics Queensland University of Technology(QUT)2 George StreetBrisbaneQLD 4001Australia Centre for Material Science Queensland University of Technology(QUT)BrisbaneQLD 4000Australia Daegyeong Regional Infrastructure Technology Development Center Kyungpook National UniversityDaegu 41566Republic of Korea James Watt School of engineering University of GlasgowG128QQUnited Kingdom Facufty of engineering and Built Environment The University of NewcastleCallaghan 2308New South WalesAustralia Department of Electrical engineering Center for Advanced PhotovoltaicsSouth Dakota State UniversityBrookings 57007South DakotaUSA Department of Physics SCSVMV Deemed UniversityKanchipuram 631561Tamil NaduIndia

Perovskite-based photovoltaic materials have been attracting attention for their strikingly improved performance at converting sunlight into *** beneficial and unique optoelectronic characteristics of perovskite structures enable researchers to achieve an incredibly remarkable power conversion *** hybrid perovskite photovoltaics promise emerging applications in a myriad of optoelectronic and wearable/portable device applications owing to their inherent intriguing physicochemical and photophysical properties which enabled researchers to take forward advanced research in this growing *** perovskite photovoltaics have attracted significant attention owing to their fascinating material properties with combined merits of high efficiency,light-weight,flexibility,semitransparency,compatibility towards roll-to-roll printing,and large-area mass-scale *** perovskite-based solar cells comprise of 4 key components that include a flexible substrate,semi-transparent bottom contact electrode,perovskite(light absorber layer)and charge transport(electron/hole)layers and top(usually metal)*** these components,interfacial layers and contact electrodes play a pivotal role in influencing the overall photovoltaic *** this comprehensive review article,we focus on the current developments and latest progress achieved in perovskite photovoltaics concerning the charge selective transport layers/electrodes toward the fabrication of highly stable,efficient flexible *** a concluding remark,we briefly summarize the highlights of the review article and make recommendations for future outlook and investigation with perspectives on the perovskite-based optoelectronic functional devices that can be potentially utilized in smart wearable and portable devices.

关键词： Perovskite photovoltaics Charge transport layers Contact interface layer Contact electrodes Printable electronics

Cardiac mechanostructure: Using mechanics and anisotropy as inspiration for developing epicardial therapies in treating myocardial infarction

在线全文

学校读者我要写书评

暂无评论

Bioactive Materials 2021年第7期6卷 2198-2220页

作者： Kiera D.dwyer Kareen L.K.Coulombe Center for Biomedical engineering School of EngineeringBrown UniversityProvidenceRIUSA

The mechanical environment and anisotropic structure of the heart modulate cardiac function at the cellular,tissue and organ *** myocardial infarction(MI)and subsequent healing,however,this landscape changes *** order to engineer cardiac biomaterials with the appropriate properties to enhance function after MI,the changes in the myocardium induced by MI must be clearly *** this review,we focus on the mechanical and structural properties of the healthy and infarcted myocardium in order to gain insight about the environment in which biomaterial-based cardiac therapies are expected to perform and the functional deficiencies caused by MI that the therapy must *** this understanding,we discuss epicardial therapies for MI inspired by the mechanics and anisotropy of the heart focusing on passive devices,which feature a biomaterials approach,and active devices,which feature robotic and cellular *** this review,a detailed analysis is provided in order to inspire further development and translation of epicardial therapies for MI.

关键词： Anisotropy Cardiac biomechanics Epicardial therapies Ventricular restraint Cardiac tissue engineering

Use of Evapotranspiration (ET) Landfill Covers to Reduce Methane Emissions from Municipal Solid Waste Landfills

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Water Resource and Protection 2015年第13期7卷 1087-1097页

作者： Tarek Abichou Tarek Kormi Cheng Wang Haykel Melaouhia Terry Johnson Stephen dwyer Department of Civil engineering Florida State University Tallahassee FL USA Ecole Nationale d’ Ingenieurs de Gabes Department de Genie Civil Gabes Tunisia LASMAP Ecole Polytechnique de Tunisie University of Carthage Tunisia Argonne National Laboratory Chicago IL USA. Waste Management Minneapolis MN USA. dwyer engineering Albuquerque NM USA

Solid waste landfills need to have final covers to 1) reduce the infiltration of rainfall into the waste mass and 2) reduce surface greenhouse gas emissions. Most regulations require that such final covers include hydraulic barriers, such as compacted clays with or without geomembrane. Significant research has been undertaken to allow the use of evapotranspiration-based covers (often termed: Evapotranspiration (ET) Cover, Water Balance Covers, or Phyto Covers) as an alternative to the barrier concept covers. ET covers are designed so that they have the capacity to store water by the soil and also have plants or vegetation to remove the stored water. In ET covers, plant roots can enhance the aeration of soil by creating secondary macropores which improve the diffusion of oxygen into soil. Therefore, biological methane oxidation (a natural process in landfill soils) can be improved considerably by the soil structuring processes of vegetation, along with the increase of organic biomass in the soil associated with plant roots. This paper summarizes a study to investigate the capacity of an ET cover to reduce surface greenhouse gas emissions when implemented on a solid waste landfill. This study consisted of using a numerical model to estimate methane emission and oxidation through an ET cover under average climatic conditions in Bennignton, Nebraska, USA. Different simulations were performed using different methane loading flux (5 to 200 gm-2·d-1) as the bottom boundary. For all simulations, surface emissions were the lowest during the growing season and during warmer days of the year. Percent oxidation is the highest during the growing season and during warmer days. The lowest modeled surface emissions were always obtained during the growing season. Finally, correlations between percent oxidation and methane loading into simulated ET covers were proposed to estimate methane emissions and methane oxidation in ET covers.

关键词： Evapotranspiration Covers Methane Oxidation Landfills Greenhouse Gas Emissions

Challenging Nanopores with Analyte Scope and Environment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Analysis and Testing 2019年第1期3卷 61-79页

作者： Buddini I.Karawdeniya Y.M.Nuwan D.Y.Bandara Jonathan W.Nichols Robert B.Chevalier James T.Hagan Jason R.dwyer Department of Chemistry University of Rhode IslandRichard E.Beaupre Center for Chemical and Forensic Sciences140 Flagg Rd.KingstonRI 02881USA Present Address:Department of Mechanical engineering Lyle School of EngineeringSouthern Methodist UniversityDallasTX 75275USA Present Address:Nova Biomedical 200 Prospect StreetWalthamMA 02454-9141USA

Nanopores are nanofluidic channels formed through thin membranes that can deliver standout single-molecule and single-particle sensing *** targets include small molecules and nanoparticles,and the DNA,protein,and glycan biopolymers underpinning genomics,proteomics,and ***-notably even in the simplest implementation,resistive-pulse sensing-does not inherently require sample labeling and,thus,offers the potential for general sensing util-ity combined with the prospective benefits of reduced sample processing requirements.A key pursuit for biopolymer sens-ing is the characterization of monomer *** review article will provide an overview of the use of nanopores for general chemical sensing and-omics-related applications,*** broad analyte scope provides fertile ground for a discussion of principles governing nanopore sensing and considerations useful for guiding nanopore *** nanopores to be effective in the face of broad analyte scope,stringent requirements on analytical performance must be met within the particular analyte class without sacrificing the operational flexibility necessary to be responsive across classes presenting very different physical and chemical *** sample-driven challenges provide a unifying framework for discussing aspects of nanopore fabrication,properties,and integration;sensing paradigms,performance,and prospects;fundamental electrokinetic and interfacial phenomena;and practical challenges facing the use and further development of nanopore devices.

关键词： Nanopore Single-molecule sensing Nanofluidics Point-of-care Silicon nitride Resistive pulse Wearable sensors Quality assurance

The effect of electrical current on lubricant film thickness in boundary and mixed lubrication contacts measured with ultrasound

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Friction 2024年第8期12卷 1882-1896页

作者： Julio A.CAO-ROMERO-GALLEGOS Saeid TAGHIZADEH Oscar A.AGUILAR-ROSAS R.S.dwyer-JOYCE Leonardo I.FARFAN-CABRERA Tecnologico de Monterrey Escuela de Ingeniería y CienciasAve.Eugenio Garza Sada 2501MonterreyN.L.64849México Department of Mechanical engineering Leonardo Centre for TribologyUniversity of SheffieldSheffield S13JDUK

This work explores experimentally the effects of DC electrical currents on lubricant film thickness alteration in lubricated sliding steel contacts in the boundary and mixed regime as measured by *** experiments were performed in a two-electrode cell-based pin-on-disk tester instrumented with ultrasonic *** and electrified tribological tests were conducted on steel flat-on-flat contacts under various speeds and loads using both a mineral base oil and a gear *** thickness,coefficient of friction(CoF),and electrical contact resistance(ECR)were measured during short experiments(30 s)in unelectrified and electrified(1.5 and 3 A)*** results suggest that film thickness,CoF,and all ECR are altered by passing DC currents through the *** particular,film thickness increased and decreased,respectively,by applying electricity at the different speeds and loads *** alterations were majorly ascribed to oil viscosity decrease by local heat and surface oxidation caused by electrical discharge and break down at the interface.

关键词： electrified sliding ultrasonic measurement electric vehicles pin-on-disk

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

煤矿充填固碳理论基础与技术构想

煤炭科学技术 2024年第2期52卷 292-308页

作者：刘浪方治余王双明高过斌张波赵玉娇朱梦博刘志超王晶钰周静李艳王美张小艳 ZHOU Song 贾奇锋西安科技大学能源学院陕西西安710054 西安科技大学煤炭绿色开采地质研究院陕西西安710054 西安科技大学地质与环境学院陕西西安710054 国能锦界能源有限责任公司陕西榆林719300 武汉理工大学材料科学与工程学院湖北武汉430070 西安财经大学商学院陕西西安710100 CSIRO Energy 10 Murray Dwyer CctMayfield West NSW 2304

在国家“双碳”目标背景下,如何减少煤炭行业的碳排放、实现碳封存已成为亟待解决的难题。煤炭行业作为高碳化石能源生产者和主体碳排放源提供者,在生产和消费过程中引发的大宗固废堆存、大型采空区形成和大量CO_(2)排放是制约煤炭可持... 详细信息

在国家“双碳”目标背景下,如何减少煤炭行业的碳排放、实现碳封存已成为亟待解决的难题。煤炭行业作为高碳化石能源生产者和主体碳排放源提供者,在生产和消费过程中引发的大宗固废堆存、大型采空区形成和大量CO_(2)排放是制约煤炭可持续开发利用与绿色健康发展的瓶颈所在。为协同解决二氧化碳封存与矿山固废消纳问题,将大宗固废处置、固废高值化利用、CO_(2)封存、采空区利用有机结合,提出了二氧化碳充填的理念,从碳汇能力评估角度界定了二氧化碳充填的3种类型。具体开展工作包括:①分析了CO_(2)充填料浆输运过程和矿化反应过程涉及到的基础理论,给出了各个过程的数学方程以及碳封存量计算公式,指出了温度、湿度等因素对矿化反应机理、碳封存量和充填体强度的影响规律。②总结了现阶段CO_(2)矿化的工艺方法、主要碱性工业固废的CO_(2)封存能力和CO_(2)矿化强化措施。在此基础上提出了基于直接湿法矿化和间接矿化的2种CO_(2)充填材料制备工艺,满足矿井充填的流动性、凝固特性和强度要求。③针对CO_(2)充填过程中的CO_(2)物理封存问题,提出了窄条带式胶结充填和综采架后胶结充填2种技术路径,前者通过在弱充填条带中构筑多贯通孔隙的充填体CO_(2)物理封存,后者借助充填支架和链式自行充填挡板在长壁工作面采空区中间断构筑充填带,控制顶板垮落,形成CO_(2)物理化学封存空间。④为了评估CO_(2)充填的碳平衡效果,依据全生命周期法界定了CO_(2)充填中碳足迹及碳消纳的计算边界。然后,梳理了CO_(2)充填过程中的碳足迹及碳消纳,分别考虑了CO_(2)的来源、用量、损耗、转化等因素。给出了包括原料运输、充填料浆制备、井下注入与充填等过程中的碳足迹及碳消纳计算方法。研究成果有望降低CO_(2)封存的能耗及成本,对煤炭绿色开采及其可持续开发利用具有深远的意义。

关键词： CO_(2)封存间断充填充填固碳碳足迹碳消纳

Experimental procedure for mapping Hertzian contacts

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2001年第S1期44卷 423-430页

作者： R. S. dwyer-Joyce A.M.Quinn B.W.Drinkwater Department of Mechanical engineering Mappin Street University of SheffieldSheffield S1 3JD UK Department

When ultrasound is incident at the interface between two rough surfaces some of thewave is reflected. The proportion of the wave reflected is related to the level of conformity betweenthe two surfaces. This principle is under investigation as a method to determine the area of contactand the load distribution, between contact elements in machine components. In this work theHertzian contact between a ball and a flat surface has been scanned ultrasonically. The resultingreflection maps have been related to the local nominal contact pressure within the contact by acalibration procedure. The resolution of the measurement system is of the same order as the con-tact dimensions. To interpret the results both convolution and deconvolution numerical procedureshave been used. The resulting measured contact pressures agree well with theoretical predictedHertz pressure.

关键词： contact area ultrasound rough surface contact real area of contact measurement