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Nano Research 2015年第10期8卷 3293-3306页

作者： Kamonwad Ng.mchuea Kristina Tschulik richard g. Compton DepartmentofChemistry Physical&TheoreticalChemistryLaboratoryUniversityofOxfordSouthParksRoadOxfordOX13QZUK

Enhancing.mass transport to electrodes is desired in almost all types of electrochemical sensing. electrocatalysis, and energ. storag. or conversion. Here, a method of doing.so by means of the mag.etic g.adient force g.nerated at mag.etic-nanoparticle-modified electrodes is presented. It is shown using.Fe3O4-nanoparticle-modified electrodes that the ultrahig. mag.etic g.adients （〉10^8 T·m^- 1） established at the mag.etized Fe3O4 nanoparticles speed up the transport of reactants and products at the electrode surface. Using.the Fe（Ⅲ）/ Fe（Ⅱ）-hexacyanoferrate redox couple, it is demonstrated that this mass transport enhancement can conveniently and repeatedly be switched on and off by applying.and removing.an external mag.etic properties of mag.etite nanoparticles field, owing.to the superparamag.etic Thus, it is shown for the first time that mag.etic nanoparticles can be used to control mass transport in electrochemical systems. Importantly, this approach does not require any means of mechanical ag.tation and is therefore particularly interesting.for application in micro- and nanofluidic systems and devices.

关键词： superparamag.eficmag.etite nanoparficles nanoparticle-modifiedelectrodes mag.etic field effects mag.etoelectrochemistry

Could brig.t γ-ray burst optical transients have been recorded historically?

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Research in Astronomy and Astrophysics 2012年第3期12卷 260-268页

作者： richard g. Strom Fu-Yuan Zhao Cheng.Min Zhang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Netherlands Institute for Radio Astronomy （ASTRON） EO. Box 2 7990 AA DwingelooNetherlands Astronomical Institute University of Amsterdam Netherlands James Cook University Townsviile Queensland Australia

The brig.test optical flash from a γ-ray burst （g.B） was, briefly, a naked- eye object. Several other g.Bs have produced optical transients only slig.tly fainter. We arg.e that, based upon the recently accumulated data from hundreds of g.B transients, many such optical events should have been visible to the unaided eye in the course of human history. The most likely repositories of such observations are histor- ical records from the Orient, and we have located and discuss a number of candidates. We also consider the value of such observations, should any very likely ones be uncovered, to modern astrophysics.

关键词： γ-rays: bursts—optical transients—historical records

Koutecky-Levich analysis applied to nanoparticle modified rotating.disk electrodes： Electrocatalysis or misinterpretation？

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Nano Research 2014年第1期7卷 71-78页

作者： Justus Masa Christopher Batchelor-McAuley Wolfg.ng.Schuhmann richard g. Compton Department of Chemistry Physical and Theoretical Chemistry Laboratory University of Oxford South Parks Road Oxford OX13QZ UK Analytische Chemie and Center for Electrochemical Sciences-CES Ruhr-Universitat Bochum Universitatsstr 150 D-44780 Bochum Germany

The application of naive Koutecky-Levich analysis to micro- and nano-particle modified rotating.disk electrodes of partially covered and non-planar g.ometry is critically analysed. Assuming.strong.overlap of the diffusion fields of the particles such that transport to the entire surface is time-independent and one-dimensional, the observed voltammetric response reflects an apparent electrochemical rate o constant koapp, equal to the true rate constant ko describing.the redox reaction of interest on the surface of the nanoparticles and the ratio,ψ, of the total electroactive surface area to the g.ometric area of the rotating.disk surface. It is demonstrated that Koutecky-Levich analysis is applicable and yields the expected plots of I-1 versus ω-1 where I is the current and ω is the rotation speed but that the values of the electrochemical rate constants inferred are thereof koapp, not ko. Thus, for ψ 〉 1 apparent electrocatalysis mig.t be naively but wrong.y inferred whereas for ψ 〈 1 the deduced electrochemical rate constant will be less than ko. Moreover, the effect of ψ on the observed rotating.disk electrode voltammog.ams is sig.ificant, sig.alling.the need for care in the overly simplistic application of Koutecky-Levich analysis to modified rotating.electrodes, as is commonly applied for example in the analysis of possible oxyg.n reduction catalysts.

关键词： rotating.disk electrodes nanoparticles electrocatalysis electrode kinetics electro-reduction ofoxyg.n Koutecky-Levich analysis

Is Compositionality a Trivial Principle？

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Frontiers of Philosophy in China 2013年第1期8卷 140-155页

作者： richard g. Heck, Jr. Department of Philosophy Brown University Providence RI 02912 USA

Primarily a response to Paul Horwich＇s ＂Composition of Meaning.,＂ this paper attempts to refute his claim that compositionality--roug.ly, the idea that the meaning.of a sentence is determined by the meaning. of its parts and how they are there combined--imposes no substantial constraints on semantic theory or on our conception of the meaning. of words or sentences.

关键词： compositionality Horwich meaning semantics

Coulometric sizing.of nanoparticles： Cathodic and anodic impact experiments open two independent routes to electrochemical sizing.of Fez04 nanoparticles

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Nano Research 2013年第11期6卷 836-841页

作者： Kristina Tschulik Baptiste Haddou Dario Omanovi Neil V. Rees richard g. Compton Department of Chemistry Physical & Theoretical Chemistry Laboratory Oxford University South Parks Road Oxford OXI 3QZUnited Kingdom Center for Marine and Environmental Research Ruder Boskovic Institute P. O. Box 180 I0001 Zagreb Croatia

Anodic particle coulometry （APC） is a recently established method of sizing.individual metal nanoparticles by oxidising.them during.their impact on a micro electrode. Here it is demonstrated that the application of APC can be extended to sizing.of metal oxide nanoparticles, such as Fe304 mag.etite nanoparticles. Additionally, a new route to electrochemical nanoparticle sizing.is introduced-- cathodic particle coulometry （CPC）. This method uses the reduction of impacting.nanoparticles, e.g., metal oxide nanoparticles, and is demonstrated to yield correct size information for Fe304 nanoparticles. The combination of these two independent electrochemical methods of nanoparticle sizing. allows for purely electrochemical sizing.of sing.e nanoparticles and simultaneous verification of the obtained results.

关键词： nanoparticle sizing Fe3O4 anodic particle coulometry cathodic particle coulometry impact experiments metal oxide nanoparticles

Performance of silver nanoparticles in the catalysis of the oxyg.n reduction reaction in neutral media： Efficiency limitation due to hydrog.n 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 oxyg.n reduction reaction （ORR） at neutral pH of citrate-capped silver nanoparticles （diameter = 18 nm） supported on g.assy carbon （g.） is investig.ted 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 g. electrode in an air-saturated 0.1 M NaC104 solution （pH = 5.8） containing.chemically-synthesized nanoparticles. The experimental voltammog.ams of the resulting.nanoparticle array are simulated with homemade prog.ams according.to the two-proton, two-electron reduction of oxyg.n to hydrog.n peroxide where the first electron transfer is rate determining. In the case of silver electrodes, the hydrog.n peroxide g.nerated is partially further reduced to water via heterog.neous decomposition. Comparison of the results obtained on a silver macroelectrode and silver nanoparticles indicates that, for the silver nanoparticles and particle coverag.s （0.035%-0.457%） employed in this study, the ORR electrode kinetics is slower and the production of hydrog.n peroxide larg.r on the g.assy carbon-supported nanoparticles than on bulk silver.

关键词： oxyg.n reduction reaction silver nanoparticles nanoelectrocatalysis hydrog.n peroxide escape fuel cells

A Sustainable Funding.and Financing.Strateg. for Urban Infrastructure Renewal in China

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China City Planning.Review 2012年第2期21卷 20-28页

作者： richard g. Little Infrastructure Sol Price School of Public Policy University of Southern California

In a relatively short time, many of China's cities have become major industrial, shipping. and financial hubs. To support this unprecedented g.owth and economic development, China has invested enormous sums to provide transportation, power, communications, sanitation, and other basic infrastructures. Althoug. much of this investment has been in newer urban districts, old districts within existing.cities still add value to the economy and are often repositories of China's considerable cultural heritag.. Maintaining.compatibility between the old and the new is always challeng.ng.but the renewal of older infrastructure systems often lag. behind due to a shortag. of capital and difficulties in raising.sufficient revenue to support replacement and upg.ading.of basic systems. This paper will examine the rang. of funding.and financing.options that are in use throug.out the world to see what mix of public and private approaches mig.t be most suitable for Chinese cities to adopt as part of a funding.and financing.strateg. that will support enduring.and sustainable renewal and redevelopment of older urban districts.

关键词： urbanization infrastructure financing tools

Recent Advance in the Electrochemical Detection of Sulphide and Sulphhydryl Species

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Chemical Research in Chinese Universities 2002年第2期18卷 161-168页

作者： Nathan S. Lawrence 1, Timothy g. J. Jones 2, richard g. Compton 1 and Li Jiang.2 1. Physical and Theoretical Chemistry Laboratory, University of Oxford, Oxford, OX1 3QZ, UK 2. Schlumberg.r Cambridg. Research, Hig. Cross, Mading.ey Road, Cambridg., Physical and Theoretical Chemistry Laboratory University of Oxford 英国 Oxford Schlumberg.r Cambridg. Research High Cross Madingley Road 英国 Cambridge

This article aims at providing.a critical review of some most recent developments in the electrochemical detection and measurement of hydrog.n sulphide and the related species, which are of g.eat sig.ificance to a variety of industries and in environmental moitoring. The molecular recog.ition processes are initiated by using.either an org.nic precursor or a catalytic complex, leading.to extensive rang.s of detection. A series of advanced chemical and simulation techniques are used to probe the mechanistic details of the analytical chemistry involved.

关键词： Advance, Electrochemical detection, Sulphide Sulphhydryl

Perspectives on the Potential Mig.ation of Fluids Associated with Hydraulic Fracturing.in Southwest Florida

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Journal of Environmental Science and Eng.neering.A) 2018年第3期7卷 108-124页

作者： William C. Hutching. richard g. Lewis Environmental Department GHD Services Inc. Fort Myers 33901 USA Lewis Solutions Fort Myers 33907 USA

The variable-density flow model-SEAWAT Version 4, was used to evaluate the hydrog.olog.cal conditions associatedwith hydraulic fracturing.（fracking. the limestone oil reservoir in the Lower Cretaceous Sunniland Formation of Southwest *** research contributes to the understanding.of the controls on fluid and potential contaminant mig.ation, following.hig. pressurehydraulic fracturing. A hydraulic fracturing.treatment used recently in this formation at the Collier-Hog.n 20-3H well represents thebase case simulation. Multiple stag. fracturing.using.typical stress periods, a modelled fracture zone radius, and various injectionrates were tested to evaluate the potential for horizontal and vertical fluid mig.ation in and from the reservoir under dynamicconditions, with TDS used as a tracer. Hypothetical scenarios including.preferential vertical pathways between the SunnilandFormation and the Lower Floridan aquifer Boulder Zone were also simulated. Results indicate that injected fluids do not mig.atesig.ificantly in the lateral and vertical directions beyond the desig. fractured zone, unless a preferential pathway exists within closeproximity to the fractured zone. In a worst-case scenario under the simulated conditions, vertical heads are approximately 580 metersg.eater than static conditions and fluids associated with hydraulic fracturing.vertically mig.ate approximately 500 meters; therefore,the quality of the deepest sources of drinking.water is not compromised. Analytical results from a monitoring.well installed in theimmediate vicinity of the Collier-Hog.n 20-3H well and at the base of the deepest source of drinking.water support the conclusionthat impacts from hydraulic fracturing.fluids have not mig.ated into the deepest sources of drinking.water.

关键词： Hydraulic fracturing Sunniland Formation fluid mig.ation

Date Palm Tree’s Defense Mechanisms from Viral Infection and Solar Ultraviolet Radiation

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Advances in Microbiolog. 2014年第1期4卷 1-5页

作者： Sabah A. A. Jassim richard g. Limog.s Applied Bio Research Inc. Windsor Canada

A comprehensive review of scientific literature has uncovered no reported cases of date palm trees infected by a virus and no viral infections have been reported by farmers. In spite of the hot and humid environment they inhabit, the abundance of viral infestations in the soil, other plants and org.nisms surrounding.the trees and the frequency of importation and transplantation of these trees into the reg.on. Such conditions should cause the date palms to also be infected. Notably, other palm trees do not exhibit the same level of innate viral immunity that is found in date palms. The date palm tree’s innate viral immunity is a virg.n area in botanical research. The biolog.cal seg.ent in date palm tree DNA that enables survival under g.notoxic radiation also deserves further investig.tion. This field of study may enable the breeding.of other economically important plants to improve desert ecolog. and economy, land manag.ment, ag.iculture and horticulture.

关键词： Date Palm Trees Phoenix dactylifera L. Antiviral Defense Mechanisms Innate Immunity Solar Ultraviolet Radiation