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Long-term Integration Ability of the Submillimeter Wave Astronomy Satellite(SWAS)Spectral Line Receivers

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Research in Astronomy and Astrophysics 2024年第6期24卷 315-322页

作者： Bing-Ru Wang Di Li paul f.Goldsmith jingwen Wu Chao-Wei Tsai Rudolf Schieder Gary j.Melnick National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Research Center for Astronomical Computing Zhejiang LaboratoryHangzhou 311100China jet Propulsion Laboratory California Institute of TechnologyPasadenaCA 91109USA Institute for frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China KOSMA I.Physik.InstitutUniversität zu KölnZülpicher Str.7750937 KölnGermany Center for Astrophysics|Harvard&Smithsonian 60 Garden StreetMS 66CambridgeMA 02138USA

The Submillimeter Wave Astronomy Satellite(SWAS)was the first space telescope capable of high spectral resolution observations of terahertz spectral *** have investigated the integration ability of its two receivers and spectrometer during five and a half years of on-orbit *** CI,O_(2),H_(2)O,and^(13)CO spectra taken toward all observed Galactic sources were *** present results are based on spectra with a total integration time of up to 2.72×10~4hr(■10~8s).The noise in the spectra is generally consistent with that expected from the radiometer equation,without any sign of approaching a noise *** noise performance reflects the extremely stable performance of the passively cooled front end as well as other relevant components in the SWAS instrument throughout its mission lifetime.

关键词： telescopes space vehicles:instruments instrumentation:miscellaneous ISM:lines and bands

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70kV和80kV影像质量比较:应用于儿科心脏CT

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国际医学放射学杂志 2015年第1期 92-93页

作者： S.Durand j.f.paul Radiology Department Institut Mutualiste Montsouris

目的评估产生相同CT剂量指数的不同k V-m As组合的噪声水平和对比噪声比（CNR）。比较80 k V与70 k V。方法用10个10;8 cm不同直径的卵圆形水模型测量噪

关键词：剂量指数对比噪声比 As CNR 噪声水平 CT 对比增强 kV

A vectorial model for the nonlinear gradient force exerted on metallic Rayleigh nanoparticles

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Chinese Optics Letters 2024年第2期22卷 207-213页

作者：朱政张聿全闵长俊 Aurèle j.LAdam H.paul Urbach 袁小聪 Research Center for Humanoid Sensing Research Institute of Intelligent SensingZhejiang LabHangzhou 311100China Nanophotonics Research Center Institute of Microscale Optoelectronics&State Key Laboratory of Radio Frequency Heterogeneous IntegrationShenzhen UniversityShenzhen 518060China Optics Research Group ImPhys DepartmentFaculty of Applied SciencesDelft University of TechnologyDelft 2628 CJThe Netherlands

Optical tweezers have proved to be a powerful tool with a wide range of *** gradient force plays a vital role in the stable optical trapping of *** scalar method is convenient and effective for analyzing the gradient force in traditional optical ***,when the third-order nonlinear effect of the nano-object is stimulated,the scalar method cannot adequately present the optical response of the metal nanoparticle to the external optical ***,we propose a theoretical model to interpret the nonlinear gradient force using the vector *** combining the optical Kerr effect,the polarizability vector of the metallic nanoparticle is derived.A quantitative analysis is obtained for the gradient force as well as for the optical potential *** vector method yields better agreement with reported experimental *** suggest that this method could lead to a deeper understanding of the physics relevant to nonlinear optical trapping and binding phenomena.

关键词： gradient forces nonlinear effect metallic nanoparticles

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A marathon,not a sprint:Increasing population physical activity as a legacy of sports mega-events

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journal of Sport and Health Science 2024年第6期13卷 732-735页

作者： fiona C.Bull paul j.Simpson Physical Activity Unit Department of Health PromotionWorld Health OrganizationGeneva CH-1211Switzerland The BMj London WC1H 9JPUK

*** matters The withdrawal of Australia as hosts for the Commonwealth Games in 2026 demonstrates that large international sporting events are more than just sporting mastery,medals,and *** also matters.1 The cost of hosting a major international tournament is eye-wateringly *** governments need to show that the billions of dollars of investment deliver a return beyond sporting glory to justify the resources that are spent.

关键词： return dollar sport

Thermo-kinetic characteristics on stabilizing hetero-phase interface of metal matrix composites by crystal plasticity finite element method

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journal of Materials Science & Technology 2024年第2期169卷 53-67页

作者： Y.B.Zhang S.j.Song f.Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Analytical&Testing Center Northwestern Polytechnical UniversityXi’an 710072China

Using dislocation-based constitutive modeling in three-dimension crystal plasticity finite element(3D CPfE)simulations,co-deformation and instability of hetero-phase interface in different material systems were herein studied for polycrystalline metal matrix composites(MMCs).Local stress and strain fields in two types of 3layer MMCs such as fcc/fcc Cu-Ag and fcc/bcc Cu-Nb have been predicted under simple compressive ***,more severe strain-induced interface instability can be observed in the fcc/bcc systems than in the fcc/fcc systems upon refining to metallic nanolayered composites(MNCs).By detailed analysis of stress and strain localization,it has been demonstrated that the interface instability is always accompanied by high-stress concentration,i.e.,thermodynamic characteristics,or high strain prevention i.e.,kinetic characteristics,at the hetero-phase *** then follows that the thermodynamic driving forceG and the kinetic energy barrier Q during dislocation and shear banding can be adopted to classify the deformation modes,following the so-called thermo-kinetic *** by inserting a high density of high-energy interfaces into the Cu-Nb composites,such thermo-kinetic integration at the hetero-phase interface allows a successful establishment of MMCs with the high△G-high Q deformation mode,which ensures high hardening and uniform strain distri-bution,thus efficiently suppressing the shear band,stabilizing the hetero-phase interface,and obtaining an exceptional combination in strength and *** hetero-phase interface chosen by a couple of thermodynamics and kinetics can be defined as breaking the thermo-kinetic correlation and has been proposed for artificially designing MNCs.

关键词： Thermodynamics and kinetics Physics-based constitutive modeling Hetero-phase interface Crystal plasticity finite element

Thermoluminescence characterization of natural and synthetic irradiated Ce-monazites

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journal of Rare Earths 2024年第4期42卷 643-650页

作者： V.Correcher C.Boronat j.Garcia-Guinea j.f.Benavente T.Rivera-Montalvo CIEMAT Av.Complutense 4028040MadridSpain MNCN-CSIC J.Gutierrez Abascal 228006MadridSpain Instituto Politécnico Nacional CICATA-IPNAv.Legaria 694Mexico City11500Mexico

The thermoluminescence(TL)emission of synthetic and natural Ce-monazites was characterized here to determine the potential application in the identification of microscopic defects from a qualitative point of view trying to link each TL peak to a chemical-physical *** kinetic parameters that lead the luminescence processes were calculated by means of variable heating rate and computing glow curve deconvolution methods and allow identifying three groups of components at~90,130 and 290℃(for the mineral sample)and~90,170,220,270 and 320℃(for the synthetic CePO_(4):Nd_(0.20),La_(0.25)).The main differences appreciated in these complex TL curves are mainly due to(i)the content of impurities(natural sample contains lanthanides as well as U 0.60%and Th 5.22%)and(ii)the degree of crystallinity of the samples which is directly related to the type of impurities(synthetic monazite relies only on Nd and La).The behavior of the dose response in the range of 1-8 Gy is similar for both samples;the TL intensity increases linearly as the dose increases without changes in the position of the maxima,denoting first-order kinetic luminescence *** peak could be mostly associated with structural defects(i.e.,phase transitions),chemical reactions(i.e.,Ce3+?Ce4+redox reaction,dehydration or dehydroxylation processes)or intrinsic defects(i.e.,frenkel defects,ODCs or NBOHCs).

关键词： Thermoluminescence Kineticparameters Phosphate Ce-monazite Defects Rare earths

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Resistive field generation in intense proton beam interaction with solid targets

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Matter and Radiation at Extremes 2024年第1期9卷 35-43页

作者： W.Q.Wang j.j.Honrubia Y.Yin X.H.Yang f.Q.Shao Department of Physics National University of Defense TechnologyHunanChina ETSI Aeronáutica y del Espacio Universidad Politécnica de MadridMadridSpain Department of Nuclear Science and Technology National University of Defense TechnologyHunanChina

The Brown-Preston-Singleton(BPS)stopping power model is added to our previously developed hybrid code to model ion beam-plasma *** simulations show that both resistive field and ion scattering effects are important for proton beam transport in a solid target,in which they compete with each *** the target is not completely ionized,the self-generated resistive field effect dominates over the ion scattering ***,when the target is completely ionized,this situation is ***,it is found that Ohmic heating is important for higher current densities and materials with high *** energy fraction deposited as Ohmic heating can be as high as 20%-30%.Typical ion divergences with half-angles of about 5°-10°will modify the proton energy deposition substantially and should be taken into account.

关键词： interaction beam intense

Effects of pyrethroid and organophosphate insecticides on reared black soldier fly larvae(Hermetia illucens)

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Insect Science 2024年第3期31卷 817-834页

作者： Nathan Meijer Lisa Zoet Theo de Rijk paul Zomer Deborah Rjkers H.j.van der fels-Klerx joop j.A.van Loon Wageningen food Safety Research(WfSR) Part of Wageningen University and ResearchWageningenThe Netherlands Bestico B.V. Industrieweg 6Berkel en RodenrjsThe Netherlands Plant Sciences Group Laboratory of EntomologyWageningen UniversityWageningenTheNetherlands

Black soldier fly larvae(Hermetia illucens)receive growing interest as a potential alternative animal feed *** insects may be exposed to insecticide residues in the rearing *** study aimed to investigate the effects of six different pyrethroid and organophosphate insecticides on this insect species'*** toxicity of two"model"substances for each of these classes(cypermethrin;pirimiphosmethyl)was quantified,with and without the synergist piperonyl butoxide(PBO).Critical effect doses corresponding to 10%yield(CED10)for cypermethrin(0.4 mg/kg)and pirimiphos-methyl(4.8 mg/kg)were *** addition of PBO to cypermethrin enhanced its relative potency with a factor *** data were compared against the relative toxicity of two analogue substances in each class(permethrin,deltamethrin;chlorpyrifosmethyl,malathion).Results suggest that exposure to concentrations complying with legal limits can cause significant reductions in *** to multiple substances at lower concentrations resulted in negative additive and synergistic *** the tested substances,deltamethrin was most toxic,causing 94%yield at 0.5 mg/*** results suggested that transfer of tested substances to the larval biomass was substance-and concentration-specific,but appeared to be correlated to reduced yields and the presence of *** of organophosphates was overall low(from 8%to 75%for *** to very low limits in insect biomass(~0.01 mg/kg),high transfer may result in *** is recommended that rearing companies implement lower contractual thresholds,and that policymakers consider adjusting legally allowed maximum residue levels in insect feed.

关键词： feed insects pesticides rearing substrate

On the analytical solution of transient friction in channel flows

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1447-1466页

作者： f.j.GARCíA-GARCíA P.fARI?AS-ALVARI?O Department of Naval & Industrial Engineering Polytechnic School of EngineeringUniversity of A Coru?a Campus Industrial de Ferrol Integraciones Técnicas de Seguridad S.A. Pol.Ind.Espíritu Santo

The transient friction in channel mean flows is the sum of two contributions,i.e., the underlying laminar flow(ULf) and the purely turbulent component(PTC), and the contributions are analyzed separately by theoretical experiments. It is found that,the transient friction may be higher or remarkably lower than that in equal-Reynolds number steady-state flows. The universal time constant for plane-parallel laminar flows is reported, and the role of the time constant in a turbulent mean flow is examined. It is shown that the time constant is related to the turbulence's frozen time. finally, a study of the logarithmic layer during the transient flow is accomplished, which shows that the logarithmic layer is destroyed.

关键词： 76D05 76D06 76f55 O361 transient flow transient friction unsteady channel flow