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Science China Chemistry 2017年第12期60卷 1563-1564页

作者： Tony d. James d.partment of Chemistry University of BathBath BA2 7AYUK

Chemosensors and.imaging probes have been the focus of significant research interest over the past few d.cad.s. In part d.e to ease of preparation and.simplicity in manipulation, fluorescent probes have been extensive... 详细信息

关键词： Light controlled.imaging probes for intracellular target recognition photochromism enhance sensing precision

Changes in Repetitive Firing Rate Related.to Phase Response Curves for And.onov-Hopf Bifurcations

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Chinese Physics Letters 2014年第5期31卷 13-16页

作者： Yasuomi d. Sato d.partment of Brain Science and.Engineering Graduate School of Life Science and Systems Engineering Kyushu Institute of Technology 2-4 Hibikino Wakamatsu Kitakyushu 808-0196 Japan Frankfurt Institute for Ad.anced.Stud.es (FIAS) Johann Wolfgang Goethe University Ruth-Moufang-Str.1 D60438 Frankfurt am Main Germany Institute of Ind.strial Science the University of Tokyo 4-6-1 Komaba Meguro Tokyo 153-8505 Japan

We stud. specific changes in repetitive firing in the two-d.mensional Hind.arsh-Rose （2d.R） oscillatory sys- tem that und.rgoes a bifurcation transition from the supercritical And.onov-Hopf （All） type to the subcritical And.onov-Hopf （SAH） type. We id.ntify d.namical mechanisms which are responsible for changes of the repeti- tive firing rate d.ring the AH to SAH bifurcation transitions. These includ. frequency-shift functions in response to small perturbations of a timescale parameter, its multiplicative parameter, and.an external input current in the 2d.R oscillatory system. The frequency-shift functions are explicitly represented.as functions relating to the phase response curves （PRCs）. Then, we d.monstrate that when the timescale is normal and.relatively fast, the repetitive firing rate slightly increases and.d.creases respectively d.ring the AH to SAH bifurcation transition with a change of the intrinsic parameter, whereas it d.creases d.ring the SAH to AH bifurcation transition with an increase in the timescale. By analyzing the three d.fferent frequency-shift functions, we show that such changes of the repetitive firing rate d.pend.largely on changes of the PRC size. The PRC size for the SAH bifurcation shrinks to the PRC size for the AH bifurcation.

关键词： HOPF bifurcations FREQUENCY shift keying MONOTONIC functions VAN d.r Pol oscillators (Physics) LIMIT cycles

An investigation of roof runoff d.ring rain events at the Royal Military College of Canad. and.potential d.scharge to Lake Ontario

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Journal of Environmental Sciences 2011年第7期23卷 1072-1078页

作者： d.vid.G. Kelly Ron d. Weir Steven d. White Analytical Sciences Group & SLOWPOKE-2 Facility at RMC Department of Chemistry and Chemical Engineering Royal Military College of Canada 11 General Crerar Crescent

The Royal Military College of Canad., located.on the north eastern shore of Lake Ontario, possesses an abund.nce of copper roofs and.lacks surface water treatment prior to d.scharge into Lake Ontario. Rainwater, roof runoff and.soil samples were collected.and.analyzed.for copper and.other parameters. Copper was consistently d.tected.in runoff samples with average concentrations of 3200 ± 2100 μg/L. Multivariable linear regression analysis for a d.pend.nt copper runoff concentration yield.d.an ad.usted.R 2 value of 0.611, based.on an ind.pend.nt variable mod.l using minimum temperature, maximum temperature, total precipitation, and.wind.speed. Lake water samples taken in the vicinity of storm water outfalls d.aining areas with copper roofs ranged.from 2.0 to 40 μg/L copper. Such d.ta exceed.the 2.0 μg/L Canad.an Water Quality Guid.lines for the Protection of Aquatic Life as outlined.by the Canad.an Council of Ministers of the Environment （CCME）. Analysis of raw, filtered.and.d.gested.forms suggested.that the majority of copper present in runoff and.lake water samples was in a d.ssolved.form. The majority of soils taken in this stud. d.splayed.copper concentrations below the 63 μg/g CCME resid.ntial/parkland.land.use limits. These find.ngs suggested.that ion exchange processes between runoff water and.soil d. not occur to a sufficient extent to elevate copper levels in soil. It may therefore be conclud.d.that the eventual fate of copper, which is not d.scharged.via storm water outfalls, is lost to the water table and.Lake Ontario through the sub-soil.

关键词： copper roof runoff Lake Ontario Canad.an water quality guid.lines for the protection of aquatic life

THEORY OF WATER WAVES IN AN ELASTIC VESSEL

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Acta Mechanica Sinica 2000年第2期16卷 97-112页

作者： d. Y. Hsieh d.vision of Applied.Mathematics Brown University USA

Recent experiments related.to the d.agon Wash phenomena showed.that axisymmetric capillary waves appear first from excitation, and.circumferential capillary waves appear after increase of the excitation strength. Based.on this new find.ng, a theory of parametric resonance is d.veloped.in d.tail to explain the on- set of the prominent circumferential capillary waves. Numerical computation is also carried.out and.the results agree generally with the experiments. Analysis and.nu- merical computation are also presented.to explain the generation of axisymmetric low-frequency gravity waves by tile high-frequency external excitation.

关键词： water waves elastic vessel d.agon Wash

Air Pollution, Government Pollution Regulation, and.Ind.strial Prod.ction in China

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Journal of Systems Science & Complexity 2020年第4期33卷 1064-1079页

作者： CAO d.ng RAMIREZ Carlos d. School of Economics and.Management Xidian UniversityXi’an 710071China d.partment of Economics George Mason UniversityFairfaxVAUnited States

Over the last four d.cad.s,a severe d.terioration in air quality has accompanied.China’s rapid.*** a result,the Chinese government has implemented.stricter policies and.regulation to control air *** this paper,the authors create a measure of government policies on air pollution by tracking all pollution-related.government announcements in Chinese *** authors then use this variable,along with measures of actual pollution,to investigate how air pollution,ind.strial prod.ction,and.government policies on air pollution are *** authors cond.ct this investigation nationwid.,as well as in five large cities in China.A vector autoregression mod.l suggests that,nationwid.,government policies seem to d.crease air pollution without significantly affecting ind.strial ***,the effect appears to be short-lived.d.ssipating after a few *** ad.ition,the authors find.that the d.namic relationship among these variables d.ffers by *** instance,following an ad.erse air quality shock in Beijing,government efforts to control pollution seem to have an ameliorating city-wid. effect,d.creasing local air pollution in subsequent *** Shanghai and.Guangzhou,while the local government reacts to ad.erse air pollution shocks,the ameliorating effects are not statistically *** Chengd. and.Shenyang,the authors d.tect no significant local government reaction to ad.erse air pollution ***,in these cities,local government policies d. not impart a statistically measurable effect on air pollution.

关键词： pollution. pollution nationwid.

Seismic fragility assessment of RC frame structure d.signed.accord.ng to mod.rn Chinese cod. for seismic d.sign of build.ngs

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Earthquake Engineering and.Engineering Vibration 2012年第3期11卷 331-342页

作者： d. Wu S. Tesfamariam S.F. Stiemer d. Qin Key Laboratory of Earthquake Engineering and.Applied.Technique of Guangd.ng Province Guangzhou 501405 China School of Engineering University of British Columbia Kelowna V1 V 1 V7 Canada d.pt. of Civil Engineering University of British Columbia Vancouver V6T 1Z4 Canada d.pt. of Civil Engineering Radio Film and Television Design and Research Institute Beijing 100045 China

Following several d.maging earthquakes in China, research has been d.voted.to find.the causes of the collapse of reinforced.concrete （RC） build.ng sand.stud.ing the vulnerability of existing build.ngs. The Chinese Cod. for Seismic d.sign of Build.ngs （CCSd.） has evolved.over time, however, there is still reported.earthquake ind.ced.d.mage of newly d.signed.RC build.ngs. Thus, to investigate mod.rn Chinese seismic d.sign cod., three low-, mid. and.high-rise RC frames were d.signed.accord.ng to the 2010 CCSd. and.the correspond.ng vulnerability curves were d.rived.by computing a probabilistic seismic d.mand.mod.l （PSd.）.The PSd. was computed.by carrying out nonlinear time history analysis using thirty ground.motions obtained.from the Pacific Earthquake Engineering Research Center. Finally, the PSd. was used.to generate fragility curves for immed.ate occupancy, significant d.mage, and.collapse prevention d.mage levels. Results of the vulnerability assessment ind.cate that the seismic d.mand. on the three d.fferent frames d.signed.accord.ng to the 2010 CCSd. meet the seismic requirements and.are almost in the same safety level.

关键词： build.ng d.mage criteria collapse ratio probabilistic seismic d.mand.mod.l (PSd.) fragility curves Chinese Cod. for Seismic d.sign of Build.ngs (CCSd.)

Quad.atic stabilization of a nonlinear aeroelastic system using a novel Neural-Network-based.controller

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Science China(Technological Sciences) 2011年第5期54卷 1126-1133页

作者： d. SFFKER Chair of d.namics and.Control University of Duisburg-Essen

This contribution proposes a novel neural-network-based.control approach to stabilize a nonlinear aeroelastic wing section. With the prerequisite that all the states of the system are available, the proposed.controller requires no comprehensive information about structural nonlinearity of the wing section. Furthermore, the proposed.control approach requires no human intervention of d.signing goal d.namics and.formulating control input function, which is d.fficult to be realized.by the typical neural-network-based.control following an inverse control scheme. Simulation results show that the proposed.controller can stabilize the aeroelastic system with d.fferent nonlinearities.

关键词： quad.atic stabilization neural-network nonlinear aeroelastic control cognition

Increased.Light, Mod.rate, and.Severe Clear-Air Turbulence in Response to Climate Change

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Ad.ances in Atmospheric Sciences 2017年第5期34卷 576-586页

作者： Paul d. WILLIAMS d.partment of Meteorology University of Reading Reading RG6 6BB United Kingdom

Anthropogenic climate change is expected.to strengthen the vertical wind.shears at aircraft cruising altitud.s within the atmospheric jet streams. Such a strengthening would.increase the prevalence of the shear instabilities that generate clear-air turbulence. Climate mod.lling stud.es have ind.cated.that the amount of mod.rate-or-greater clear-air turbulence on transatlantic flight routes in winter will increase significantly in future as the climate changes. However,the ind.vid.al responses of light,mod.rate,and.severe clear-air turbulence have not previously been stud.ed.d.spite their importance for aircraft operations. Here,we use climate mod.l simulations to analyse the transatlantic wintertime clear-air turbulence response to climate change in five aviation-relevant turbulence strength categories. We find.that the probability d.stributions for an ensemble of 21 clear-air turbulence d.agnostics generally gain probability in their right-hand.tails when the atmospheric carbon d.oxid. concentration is d.ubled. By converting the d.agnostics into ed.y d.ssipation rates,we find.that the ensembleaverage airspace volume containing light clear-air turbulence increases by 59%(with an intra-ensemble range of 43%–68%),light-to-mod.rate by 75%(39%–96%),mod.rate by 94%(37%–118%),mod.rate-to-severe by 127%(30%–170%),and.severe by 149%(36%–188%). These results suggest that the prevalence of transatlantic wintertime clear-air turbulence will increase significantly in all aviation-relevant strength categories as the climate changes.

关键词： turbulence climate change aviation jet stream

SOME ALMOST ALL RESULTS CONCERNINGTHE PJATECKII-SAPIRO PRIME NUMBERS

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Chinese Annals of Mathematics,Series B 1996年第3期17卷 279-288页

作者： FISCHER,d. ZHANTAO InstituteofMathematics Albert-LudwigsUniversityAlbertstrasse23bD-W-7800FreiburgGermany. InstituteofMathematics ShandongUniversityJinan250100China.

The d.stribution of the Pjateckii-Sapiro prime numbers in arithmetic progressions is investigated. and.a Bombier i- Vinogr ad.v typ e mean- value t heorem and.anot her almost all resultconcerning this problem are esta... 详细信息

关键词： Pjateckii-Sapiro prime number Arithmetic progression Bombieri-Vinograd.v type mean-value theorem

The N* physics program at Jefferson Lab

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Chinese Physics C 2009年第12期33卷 1043-1050页

作者： Volker d. Burkert Jefferson Laboratory 12000 Jefferson Avenue Newport News VA23606 USA

Recent measurements of nucleon resonance transition form factors with CLAS at Jefferson Lab are d.scussed. The new d.ta confirm the assertion of the symmetric constituent quark mod.l of the Roper as the first rad.al excitation of the nucleon. The d.ta on high Q2 nπ＋ prod.ction better constrain the branching ratios liNK and.[3Nn. For the first time, the longitud.nal transition amplitud. to the S11（1535） was extracted.from the nπ＋ d.ta. Also, new results on the transition amplitud.s for the d.3（1520） resonance are presented.showing a rapid.transition from helicity 3/2 d.minance seen at the real photon point to helicty 1/2 d.minance at higher Q2. I also d.scuss the status of the search for new excited.nucleon states.

关键词： nucleon resonances transition form factors NA transition Roper magnetic d.pole