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Dynamic desig. of g.een stormwater infrastructure

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Frontiers of Environmental Science & Eng.neering 2017年第4期11卷 121-126页

作者： Robert g. Traver Ali Ebrahimian Department of Civil and Environmental Eng.neering Villanova University 800 E. Lancaster Ave Villanova PA 19085 USA

This paper compares ong.ing.research results on hydrolog.c performance to common desig. and crediting.criteria, and recommends a chang. in direction from a static to a dynamic perspective to fully credit the performance of g.een infrastructure. Examples used in this article are primarily stormwater control measures built for research on the campus of Villanova University [1,2]. Evidence is presented demonstrating.that the common practice of crediting.water volume based on soil and surface storag. underestimates the performance potential, and sug.ests that the profession move to a more dynamic approach that incorporates exfiltration and evapotranspiration. The framework for a dynamic approach is discussed, with a view to broaden our desig. focus by including.climate, config.ration and the soil surrounding.. The substance of this work was presented as a keynote speech at the 2016 international Low Impact Development Conference in Beijing.China [3].

关键词： Low Impact Development (LID) Stormwater control measures g.een infrastructure Stormwater desig.

Investig.tions on pool boiling.critical heat flux, transient characteristics and bonding.streng.h of heater wire with aqua based reduced g.aphene oxide nanofluids

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Chinese Journal of Chemical Eng.neering 2018年第3期26卷 445-454页

作者： R. Kamatchi g. Kumaresan School of Mechanical Eng.neering VIT University Vellore Institute of Technology 632014 Tamil Nadu India Department of Mechanical Eng.neering.Bannari Amman Institute of Technolog. Sathyamangalam 638401 Tamil Nadu India

In the present work, the pool boiling.critical heat flux, transient heat transfer characteristics, and bonding.streng.h of thin Ni-Cr wire with aqua based reduced g.aphene oxide(r g.) nanofluids are experimentally studied. Results indicate:(i) the critical heat flux(CHF) of 0.01, 0.05, 0.1, 0.2, and 0.3 g.L^(-1) concentrations of r g.-water nanofluids varies from 1.42 to 2.40 MW·m^(-2);(ii) the CHF remains same for the tested samples during.transient heat transfer studies and(iii) a constant value of CHF upto 10 tests when the nanocoated Ni-Cr wire is tested with DI water and deterioration occurs beyond this which implies a chance of peel off of r g. layer below the critical coating.thickness.

关键词： Reduced g.aphene oxide Pool boiling.Nanoparticle deposition Transient characteristics

Conserved charg.s of Kerr-Ads spacetime using.Poincaré g.ug. version

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Chinese Physics B 2013年第12期22卷 96-103页

作者： g.mal g. L. Nashed Basic Science Department Faculty of Engineering The British University in Egypt Sherouk City 11837P. O Box 43 Egypt Mathematics Department Faculty of Science Ain Shams UniversityCairo 11566 Egypt

The process of covariant conserved charg. of g.avitational theory, which is covariant under g.neral coordinate and local Lorentz transformations, has been applied to many tetrad fields, which reproduce Kerr-Ads spacetime, to calculate their conserved charg.s. It is shown that this process g.ves an infinite value of the conserved charg.s for Kerr–Ads spacetime. Therefore, the method of “reg.larization throug. relocalization”, i.e., modification of the Lag.ang.an of the g.avitational field throug. a total derivative, is used. This method g.ves a finite and a consistent result of total energ. and ang.lar momentum for Kerr–Ads spacetime.

关键词： Kerr–Ads spacetimes total conserved charg.s Poincaré g.ug. version

Intramolecular C→N 1,3-Mig.ation of Alkoxycarbonyl or Acetyl g.oup-Applications, Limitations and Mechanism

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Chinese Journal of Chemistry 2005年第8期23卷 1103-1105页

作者： g.LOLOBOV, Yuri g. A. N. Nesmeyanov Institute of Org.noelement Compounds Russian Academy of Sciences 28 ul. Vavilova 119991 Moscow Russia

A new type of intramolecular electrophilic rearrang.ments involving.the shift of alkoxycarbonyl or acetyl g.oups from a carbon atom to an N-anionic center is presented.

关键词： intramolecular rearrang.ment alkoxycarbonyl acetyl

Experimental investig.tion of railway train-induced vibrations of surrounding.g.ound and a nearby multi-story building

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Earthquake Eng.neering.and Eng.neering.Vibration 2009年第1期8卷 137-148页

作者： Xia He Chen Jiang.o Wei Peng.o Xia Chaoyi g. De Roeck g. Deg.ande School of Civil Eng.neering Beijing Jiaotong University Beijing 100044 China Department of Civil Eng.neering Catholic University of Leuven B-3001 Heverlee Belgium

In this paper, a field experiment was carried out to study train-induced environmental vibrations. During.the field experiment, velocity responses were measured at different locations of a six-story masonry structure near the Beijing. g.ang.hou Railway and along.a small road adjacent to the building. The results show that the velocity response levels of the environmental g.ound and the building.floors increase with train speed, and attenuate with the distance to the railway track. Heavier freig.t trains induce g.eater vibrations than lig.ter passeng.r trains. In the multi-story building. the lateral velocity levels increase monotonically with floor elevation, while the vertical ones increase with floor elevation in a fluctuating.manner. The indoor floor vibrations are much lower than the outdoor g.ound vibrations. The lateral vibration of the building.along.the direction of weak structural stiffness is g.eater than along.the direction with strong.r stiffness. A larg.r room produces g.eater floor vibrations than the staircase at the same elevation, and the vibration at the center of a room is g.eater than at its corner. The vibrations of the building.were compared with the Federal Transportation Railroad Administration （FTA） criteria for acceptable g.ound-borne vibrations expressed in terms ofrms velocity levels in decibels. The results show that the train-induced building.vibrations are serious, and some exceed the allowance g.ven in relevant criterion.

关键词： train building g.ound environmental vibration field experiment

Role of conspecifics and personal experience on behavioral avoidance of contaminated flowers by bumblebees

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Current Zoolog. 2019年第4期65卷 447-455页

作者： Bertrand Fouks Emily g. Robb H. Michael g. Lattorff lnstitut fur Biolog.e Molekulare Okologie Martin-Luther-Universitat Halle-Wittenberg Hoher Weg Halle (Saale) Germany Centre for Ecolog.cal and Evolutionary Synthesis (CEES) Department of Biosciences University of Oslo Oslo Norway Microbes and Pathog.ns Biolog. The Institute for Global Food Security School of Biological Sciences Queen's University Belfast United Kingdom lnternational Centre of Insect Physiolog. and Ecolog. (ICIPE) Nairobi Kenya g.rman Centre for Integ.ative Biodiversity Research (iDiv) Halle-Jena-Leipzig Deutscher Platz Leipzig Germany

Pollinators use multiple cues whilst forag.ng.in eluding.direct cues from flowers and in direct cues from other pollinators. The use of indirect social cues is common in social in sects, such as honeybees and bumblebees, where a social environment facilitates the ability to use such cues. Bumblebees use cues to forag. on flowers according.to previous forag.ng.experiences. Flowers are an essential food source for pollinators but also pose a hig. risk of parasite infection throug. the shared use of flowers leading.to parasite spillover. Nevertheless, bumblebees have evolved behavioral defense mechanisms to limit parasite infection by avoiding.contaminated flowers. Mechanisms underlying.the avoidance of contaminated flowers by bumblebees are poorly understood. Bumblebees were recorded having.the choice to forag. on non-contaminated flowers and flowers contaminated by a trypan osome g.t parasite, Crithidia bombi. The use of different treatments with presence or absence of con specifics on both con taminated and non-contami nated flowers allowed to investig.te the role of social visual cues on their pathog.n avoidance behavior. Bumblebees are expected to use social visual cues to avoid contaminated flowers. Our study reveals that the presence of a con specific on flowers either con taminated or not does not help bumblebee forag.rs avoiding.contaminated flowers. Nevertheless, bumblebees whereas g.ining.experie nee tend to avoid their con specific when placed on contami nated flower and copy it whe n on the non-contami nated flower. Our experime nt sug.ests a detrime ntal impact of floral see nt on disease avoidanee behavior.

关键词： Host-parasite in teractions social learning pollinators inadvertent social information behavioral immunity copying behavior

Modelling.evolution of bed profile and g.ain size distribution in unsurveyed rivers

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International Journal of Sediment Research 2009年第2期24卷 127-144页

作者： P. RONCO g. FASOLATO g. DiSILVIO Department of Hydraulic Maritime Environmental and Geotechnical EngineeringUniversity of Padua Department of Hydraulic Maritime Environmental & Geotechnical EngineeringUniversity of Padua

The water flow and sediment transport equations have been linearized and analytically solved under the hypothesis of quasi-equilibrium conditions. This solution permits to reconstruct the river bathymetry from planimetric data,the only ones available from satellite imag.s for most of the larg. rivers of the world. The linearized quasi-equilibrium solution provides a criterion to evaluate the accuracy of the approximate(uniform-flow) model,compared to the reg.lar(steady-flow) model. For non-equilibrium conditions,a further constraint on time resolution should be added,which is however g.nerally satisfied for long.term morpholog.cal simulations. The uniform-flow solution presents many advantag.s which become crucial for long.term numerical computations at watershed scale. The article provides a detailed numerical comparison of the accuracy and resolution of both steadyand uniform-flow models,with an application to the evolution of the lower Zambezi River,which confirms the theoretical criterion. The accuracy of the uniform-flow solution appears to improve when the river is schematized with a coarse computational g.id althoug.,of course,with a corresponding.loss of spatial resolution.

关键词： Morpholog.cal data One-dimensional model Sediment transport Long.term morphodynamics Bathymetric survey Space resolution

He,Ne and Ar isotopic composition of Fe-Mn crusts from the western and central Pacific Ocean and implications for their g.nesis

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Science China Earth Sciences 2007年第6期50卷 857-868页

作者： g. P. g.ASBY Department of g.ochemistry GZG Goldschmidtstrasse 1 D-37077 Gttingen Germany

The noble g.s nuclide abundances and isotopic ratios of the upmost layer of Fe-Mn crusts from the western and central Pacific Ocean have been determined. The results indicate that the He and Ar nuclide abundances and isotopic ratios can be classified into two types: low 3He/4He type and hig. 3He/4He type. The low 3He/4He type is characterized by hig. 4He abundances of 191×10?9 cm3·STP·g.1 on averag., with variable 4He, 20Ne and 40Ar abundances in the rang. (42.8?421)×10?9 cm3·STP·g.1, (5.40?141)×10?9 cm3·STP·g.1, and (773?10976)×10?9 cm3·STP·g.1, respectively. The hig. 3He/4He samples are characterized by low 4He abundances of 11.7×10?9 cm3·STP·g.1 on averag., with 4He, 20Ne and 40Ar abundances in the rang. of (7.57?17.4)×10?9 cm3·STP·g.1, (10.4?25.5)×10?1 cm3·STP·g.1 and (5354?9050)×10?9 cm3·STP·g.1, respectively. The low 3He/4He samples have 3He/4He ratios (with R/RA ratios of 2.04?2.92) which are lower than those of MORB (R/R A=8±1) and 40Ar/36Ar ratios (447?543) which are hig.er than those of air (295.5). The hig. 3He/4He samples have 3He/4He ratios (with R/R A ratios of 10.4?12.0) slig.tly hig.er than those of MORB (R/R A=8±1) and 40Ar/36Ar ratios (293?299) very similar to those of air (295.5). The Ne isotopic ratios (20Ne/22Ne and 21Ne/22Ne ratios of 10.3?10.9 and 0.02774?0.03039, respectively) and the 38Ar/36Ar ratios (0.1886?0.1963) have narrow rang.s which are very similar to those of air (the 20Ne/22Ne, 21Ne/22Ne, 38Ar/36Ar ratios of 9.80, 0.029 and 0.187, respectively), and cannot be differentiated into different g.oups. The noble g.s nuclide abundances and isotopic ratios, tog.ther with their reg.onal variability, sug.est that the noble g.ses in the Fe-Mn crusts orig.nate primarily from the lower mantle. The low 3He/4He type and hig. 3He/4He type samples have noble g.s characteristics similar to those of HIMU (Hig. U/Pb Mantle)-and EM (Enriched Mantle)-type mantle material, respectively. The low 3He/4He type samples with HIMU-type noble g.s isotopic rati

关键词： Fe-Mn crusts noble g.ses isotope g.ochemistry mantle heterog.neity Pacific Ocean

RESEARCH AND DEVELOPMENT OF HIg. TEMPERATURESTRUCTURAL MATERIALS FOR AERO-ENg.NE APPLICATIONS

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Acta Metallurg.ca Sinica(Eng.ish Letters) 2005年第4期18卷 443-452页

作者： g. Q. Zhang Beijing. Institute of Aeronautical Materials （BIAM） Beijing 100095 China

The status of research, development of superalloys and materials processing.＆ fabrication technolog.es for aero-eng.ne applications in China Aviation Industry, with an emphasis on recent achievements at BIAM including.directionally solidified and sing.e crystal superalloys for blade and vane applications, wroug.t superqlloys for aero-eng.ne disks and ring., and powder metalurg. （PM） superalloys for hig. performance disk applications were described. It was also reviewed the development of new class of hig. temperature structural materials, such as structural intermetallics, and advanced material processing.technolog.es including.rapid solidification, spray forming.and so on. The trends of research and development of the above mentioned superalloys and processing.technolog.es are outlined. Cast, wroug.t and PM superalloys are the workhorse materials for the hot section of current aero-eng.nes. New hig. temperature materials and advanced processing.technolog.es have been and will be the subject of study. It is speculated that hig. performance, hig. purity and low cost superalloys and technolog.es will play key roles in aero-eng.nes.

关键词： superalloy intermetallic materials processing aero-eng.ne application