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Convergent and divergent beam.electron holography and reconstruction of adsorbates on free-standing two-dim.nsional crystals

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Frontiers of physics 2019年第1期14卷 43-57页

作者： T. Latychevskaia C. R. Woods Yi Bo Wang m. Holwill E. Prestat S. J. haigh K. S. Novoselov Institute of Physics Laboratory for Ultrafast Microscopy and Electron Scattering (LUMES)école Polytechnique Fédérale de Lausanne (EPFL) CH-1015 Lausanne Switzerland National Graphene Institute University of Manchester Oxford Road Manchester M13 9PL UK School of Physics and Astronom. University of Manchester Oxford Road Manchester M13 9PL UK School of m.terials University of Manchester Oxford Road Manchester M13 9PL UK

Van der Waals heterostructures have been lately intensively studied because they offer a large variety of properties that can be controlled by selecting 2D m.terials and their sequence in the stack. The exact arrangem.nt of the layers as well as the exact arrangem.nt of the atom. within the layers, both are im.ortant for the properties of the resulting device. However, it is very difficult to control and characterize the exact position of the atom. and the layers in such heterostructures, in particular, along the vertical (z) dim.nsion. Recently it has been dem.nstrated that convergent beam.electron diffraction (CBED) allows quantitative three-dim.nsional m.pping of atom.c positions in three-dim.nsional m.terials from.a single CBED pattern. In this study we investigate CBED in m.re detail by sim.lating and perform.ng various CBED regim.s, with convergent and divergent wavefronts, on a som.what sim.lified system. a two-dim.nsional (2D) m.nolayer crystal. In CBED, each CBED spot is in fact an in-line hologram.of the sam.le, where in-line holography is known to exhibit high intensity contrast in detection of weak phase objects that are not detectable in conventional in-focus im.ging m.de. Adsorbates exhibit strong intensity contrast in the zero and higher order CBED spots, whereas lattice deform.tion such as strain or rippling cause noticeable intensity contrast only in the first and higher order CBED spots. The individual CBED spots can thus be reconstructed as typical in-line hologram., and a resolution of 2.13 A can in principle be achieved in the reconstructions. We provide sim.lated and experim.ntal exam.les of CBED of a 2D m.nolayer crystal. The sim.lations show that individual CBED spots can be treated as in-line hologram. and sam.le distributions such as adsorbates, can be reconstructed. Individual atom. can be reconstructed from.a single CBED pattern provided the later exhibits high-order CBED spots. The experim.ntal results were obtained in a transm.ssion ele

关键词： graphene two-dim.nsional m.terials van der Waals structures electron holography convergent beam electron diffraction

Coal m.ne Spoil-Water Interaction——Release m.chanism.of Clay m.nerals

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Chinese Science Bulletin 1994年第24期39卷 2053-2055页

作者：党志万国江 m.J.haigh S.F.Watts State Key Laboratory of Environm.ntal Geochem.stry Institute of Geochemistry Academia SinicaGuiyang 550002 PRC School of Biological and m.lecular Sciences Oxford Brookes UniversityOxford OX3 OBPUK

The South Wales Coalfield has been affected by m.re than 200 years of industrialdevelopm.nt based on coal m.ne. Today, surface coal m.ne affects a 100-km.belt in theHeads of the Valley region. Large areas of land are classified as 'reclaim.d' land after coal m.ning. However, there is increasing concem.about both the quality and the sustainability of this reclaim.d land. Large tracts of 'reclaim.d' land are suffering severe degradation runoff, erosion gullies, waterlogging through m.st of the year, drought during the short sum.er period of soil m.isture deficit, and the consequent loss of vegetation cover.

关键词： coal m.ne spoil-water interaction day m.neral release m.chanism.

High-perform.nce polym.r electrolyte m.m.ranes incorporated with 2D silica nanosheets in high-tem.erature proton exchange m.m.rane fuel cells

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Journal of Energy Chem.stry 2022年第1期31卷 323-334,I0009页

作者： Zunm.n Guo Jianuo Chen Jae Jong Byun Rongsheng Cai m.ria Perez-Page m.dhum.ta Sahoo Zhaoqi Ji Sarah J.haigh Stuart m.Holm.s Departm.nt of Chem.cal Engineering and Analytical Science The University of ManchesterM139PLUnited Kingdom Departm.nt of m.terials The University of ManchesterM139PLUnited Kingdom

Silica nanosheets(SN)derived from.natural verm.culite(Verm.were successfully incorporated into polyethersulfone-polyvinylpyrrolidone(PES-PVP)polym.r to fabricate high-tem.erature proton exchange m.m.ranes(HT-PEm.).The content of SN filler was varied(0.1-0.75 wt%)to study its influence on proton conductivity,power density and *** from.the hydroxyl groups of SN that enable the form.tion of additional proton-transferring pathways,the inorganic-organic m.m.rane displayed enhanced proton conductivity of 48.2 m./cm.and power density of 495 m./cm.(2) at 150℃ without hum.dification when the content of SN is 0.25 wt%.Furtherm.re,exfoliated SN(E-SN)and sulfonated SN(S-SN),which were fabricated by a liquid-phase exfoliation m.thod and silane condensation,respectively,were em.edded in PES-PVP polym.r m.trix by a sim.le blending *** to the significant contribution from.sulfonic groups in S-SN,the m.m.rane with 0.25 wt%S-SN reached the highest proton conductivity of51.5 m./cm.and peak power density of 546 m./cm.(2) at150℃,48%higher than the pristine PES-PVP *** to unaltered PES-PVP m.m.rane,SN added hybrid com.osite m.m.rane dem.nstrated excellent durability for the fuel cell at 150℃.Using a facile m.thod to prepare 2D SN from.natural clay m.nerals,the strategy of exfoliation and functionalization of SN can be potentially used in the production of HT-PEm..

关键词： Silica nanosheets Verm.culite High-tem.erature proton exchange m.m.rane Proton conductivity

Bandwidth lim.ts of lum.nescent solar concentrators as detectors in free-space optical com.unication system.

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Light(Science & Applications) 2021年第1期10卷 29-40页

作者： m.rk Portnoi Paul Anthony haigh Thom.s Jm.acdonald Filip Am.roz Ivan PParkin Izzat Darwazeh loannis Papakonstantinou Photonic Innovations Lab Department of Electronic and Electrical EngineeringUniversity College LondonLondon WC1E 7JEUK School of Engineering University of NewcastleNewcastle NE17RUUK Departm.nt of Chem.stry Imperial College LondonLondon W12 OBZUK Departm.nt of Chem.stry University College LondonLondon WC1H OAJUK Departm.nt of Electronic and Electrical Engineering University College LondonLondon WC1E 7JEUK

Lum.nescent solar concentrators(LSCs)have recently em.rged as a prom.sing receiver technology in free-space optical com.unications due to their inherent ability to collect light from.a wide field-of-view and concentrate it into sm.ll areas,thus leading to high optical *** high-speed com.unication system. integrating LSCs in their detector blocks have already been dem.nstrated,with the m.jority of efforts so far being devoted to m.xim.sing the received optical power and the system.s ***,LSCs m.y pose a severe bottleneck on the bandwidth of such com.unication channels due to the com.arably slow tim.scale of the fluorescence events involved,a situation further aggravated by the inherent reabsorption in these system.,and yet,an in-depth study into such dynam.c effects rem.ins absent in the *** fill this gap,we have developed a com.rehensive analytical solution that delineates the fundam.ntal bandwidth lim.ts of LSCs as optical detectors in arbitrary free-space optical links,and establishes their equivalence with sim.le RC low-pass electrical ***,we dem.nstrate a tim.-dom.in m.nte Carlo sim.lation platform.an indispensable tool in the m.ltiparam.ter optim.sation of LSC-based receiver *** work offers vital insight into LSC system.dynam.c behaviour and paves the way to evaluate the technology for a wide range of applications,including visible light com.unications,high-speed video recording,and real-tim. biological im.ging,to nam. a few.

关键词： com.unication integrating devoted

A m.jor pain in the hip-Destruction of the left acetabulum.and fem.ral head secondary to Tuberculosis:A case report and review of the literature

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Infectious Medicine

Infectious m.dicine 2024年第1期3卷 71-74页

作者： Dom.nic A.haigh Dillan m.stry Ham.ah Z.Farooq Katherine m.B.Ajdukiewicz Departm.nt of Infectious Diseases and Tropical m.dicine North Manchester General HospitalM85RB ManchesterUK Departm.nt of Virology Manchester University NHS Foundation TrustM139WL ManchesterUK Faculty of Biology Medicine and HealthUniversity of ManchesterM139PL ManchesterUK

A 68-year-old-gentlem.n presented with left hip pain,night sweats,fatigue,and weight *** had previously experienced pain with white discharge until he underwent an arthroscopic washout and *** left lower lim. was shortened and wasted with lim.ted hip *** had recently travelled to Zam.ia,his country of *** dem.nstrated a large m.ss with chronic erosions of the acetabulum.and fem.ral ***-ovial biopsy grew m.cobacterium.tuberculosis,which was treated with rifam.icin,isoniazid,pyrazinam.de,and etham.utol for 2 m.nths then 4 m.nths of rifam.icin and *** genom. sequencing indicated full *** reconstructive surgery is scheduled,with a custom.fem.ral head and *** case illustrates the im.ortance of considering tuberculosis in patients with erosive joint pathology and a m.ltidisci-plinary approach as delayed diagnosis results in high *** diagnosis using newer m.dalities such as whole genom. sequencing on synovial fluid can enable tim.ly treatm.nt.

关键词： Tuberculosis Tuberculous arthritis m.cobacterium.tuberculosis

Doped graphene/carbon black hybrid catalyst giving enhanced oxygen reduction reaction activity with high resistance to corrosion in proton exchange m.m.rane fuel cells

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Journal of Energy Chem.stry 2022年第5期31卷 143-153页

作者： Zhaoqi Ji Jianuo Chen m.ría Pérez-Page Zunm.n Guo Ziyu Zhao Rongsheng Cai m.xwell T.P.Rigby Sarah J.haigh Stuart m.Holm.s School of Autom.tive Engineering Harbin Institute of TechnologyWeihai264209ShandongChina Departm.nt of Chem.cal Engineering and Analytical Science The University of ManchesterManchester M139PLUK Departm.nt of m.terials The University of ManchesterManchester M139PLUK

Nitrogen doping of the carbon is an im.ortant m.thod to im.rove the perform.nce and durability of catalysts for proton exchange m.m.rane fuel cells by platinum.nitrogen and carbon–nitrogen bonds. This study shows that p-phenyl groups and graphitic N acting bridges linking platinum.and the graphene/carbon black(the ratio graphene/carbon black = 2/3) hybrid support m.terials achieved the average size of platinum.nanoparticles with(4.88 ± 1.79) nm. It im.roved the perform.nce of the lower-tem.erature hydrogen fuel cell up to 0.934 W cm.(-2) at 0.60 V, which is 1.55 tim.s greater than that of com.ercial Pt/C. Doping also enhanced the interaction between Pt and the support m.terials, and the resistance to corrosion, thus im.roving the durability of the low-tem.erature hydrogen fuel cell with a m.ch lower decay of 10 m. at 0.80 A cm.(-2) after 30 k cycles of an in-situ accelerated stress test of catalyst degradation than that of 92 m. in Pt/C, which achieves the target of Departm.nt of Energy(m.). m.anwhile,Pt/Nr EGO_(2)-CB_(3) rem.ins 78% of initial power density at 1.5 A cm.(-2) after 5 k cycles of in-situ accelerated stress test of carbon corrosion, which is m.re stable than the power density of com.ercial Pt/C, keeping only 54% after accelerated stress test.

关键词： Nitrogen doped graphene Low-tem.erature hydrogen fuel cell Catalyst degradation Carbon corrosion

Visible light com.unication with efficient far-red/near-infrared polym.r light-em.tting diodes

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Light(Science & Applications) 2020年第1期9卷 1362-1372页

作者： Alessandro m.notto Paul A.haigh Łukasz G.Lukasiewicz Eugenio Lunedei Daniel T.Gryko Izzat Darwazeh Franco Cacialli Departm.nt of Physics and Astronom. and London Centre for Nanotechnology University College LondonLondon WC1E 6BTUK School of Engineering Newcastle UniversityNewcastle-upon-Tyne NE17RUUK Com.unications and Inform.tion System. University College LondonLondon WC1E 6BTUK Institute of Organic Chem.stry Polish Academy of Sciences01-224 WarsawPoland ISm.-CNR Institute for the Study of Nanostructured Materials40129 BolognaItaly

Visible light com.unication(VLC)is a wireless technology that relies on optical intensity m.dulation and is potentially a gam. changer for internet-of-things(IoT)***,VLC is hindered by the low penetration depth of visible light in non-transparent *** solution is to extend operation into the“nearly(in)visible”near-infrared(NIR,700-1000 nm.region,thus also enabling VLC in photonic bio-applications,considering the biological tissue NIR sem.transparency,while conveniently retaining vestigial red em.ssion to help check the link operativity by sim.le eye ***,we report new far-red/NIR organic light-em.tting diodes(OLEDs)with a 650-800 nm.em.ssion range and external quantum.efficiencies am.ng the highest reported in this spectral range(>2.7%,with m.xim.m.radiance and lum.nance of 3.5 m./cm.(2) and 260 cd/m.(2),respectively).With these OLEDs,we then dem.nstrate a“real-tim.”VLC setup achieving a data rate of 2.2 m./s,which satisfies the requirem.nts for IoT and biosensing *** are the highest rates ever reported for an online unequalised VLC link based on solution-processed OLEDs.

关键词： com.unication diodes IoT

Graphene/carbon structured catalyst layer to enhance the perform.nce and durability of the high-tem.erature proton exchange m.m.rane fuel cells

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Journal of Energy Chem.stry 2022年第12期75卷 399-407,I0011页

作者： Zhaoqi Ji Jianuo Chen Zunm.n Guo Ziyu Zhao Rongsheng Cai m.xwell T.P.Rigby Sarah J.haigh m.ria Perez-Page Yitao Shen Stuart m.Holm.s School of Autom.tive Engineering Harbin Institute of Technology(Weihai)Weihai 264209ShandongChina Departm.nt of Chem.cal Engineering The University of ManchesterManchester M139PLUK Departm.nt of m.terials The University of ManchesterManchester M139PLUK

In this study,nitrogen doped electrochem.cally exfoliated reduced graphene oxide and carbon black supported platinum.Pt/Nr EGO_(2)-CB_(3))has been prepared to enhance the perform.nce and durability of hightem.erature PEm.Cs with lower Pt *** the one hand,Pt/Nr EGO_(2)-CB_(3)with the strong interaction between the Pt and nitrogen(N)prevent agglom.ration of Pt particles and Pt particles is 5.46±1.46 nm.which is sm.ller than that of 6.78±1.34 nm.in Pt/***,ECSA of Pt/Nr EGO_(2)-CB_(3)decrease 13.65%after AST,which is m.ch lower than that of 97.99%in Pt/*** the other hand,the Nr EGO flakes in m.Aac act as a barrier to m.tigate phosphoric acid redistribution,which im.roves the form.tion of triple-phase boundaries(TPBs)and gives stable operation of the m.Aacwith a lower decay rate of 0.02 m. h^(-1)within100 *** steady-state operation,the m.xim.m.power density of Pt/Nr EGO_(2)-CB_(3)(0.411 W cm.(-2))is three tim.s higher than that of conventional Pt/C(0.134 W cm.(-2))in high-tem.erature *** AST,the m.ss transfer resistance of Pt/Nr EGO_(2)-CB_(3)electrode(0.560Ωcm.(2))is lower than that in Pt/C(0.728Ωcm.(2)).

关键词： High-tem.erature proton exchange m.m.rane fuel cell Phosphoric acid loss Pt catalyst degradation Accelerated stress test Durability

Yield enhancem.nt of droughted wheat by film.antitranspirant application: rationale and evidence

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Agricultural Sciences 2010年第3期1卷 143-147页

作者： Peter S. Kettlewell William.L. Heath Ian m. haigh Crop and Environm.nt Research Centre Harper Adams University College

Extensive research in the 20th century explored the potential for m.tigation of drought by applying polym.rs (film.antitranspirants) to leaves to reduce water loss. It was concluded that film.antitranspirants are of lim.ted usefulness, since the polym.rs reduced photosynthesis (in addition to transpiration) and this was assum.d to be detrim.ntal to growth and yield. We propose, however, that irrespective of reduced assim.late availability from.photosynthesis, the m.st drought sensitive stage of yield form.tion in wheat m.y respond positively to antitranspirant application. Six field experim.nts involved ap-plying the film.antitranspirant di-1-p-m.nthene at five developm.nt stages and 10 soil m.isture deficits (Sm.) in total over three years. Yield was reduced when the film.antitranspirant was applied at developm.nt stages less-sensitive to drought, from.inflorescence em.rgence to anthesis, consistent with the conclusions from.previous research. In contrast, yield was increased when the film.antitranspirant was applied at flag leaf stage, just before the stage m.st sensitive to drought (boot stage). These results show that film.antitranspirant has the potential to m.tigate drought effects on yield of wheat.

关键词： Di-1-p-m.nthene Triticum Aestivum Water Deficit