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Is Brenner＇s Modification to the Classical Navier-stokes Equations Able to Describe sound Propagation in Gases？

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Chinese Physics Letters 2008年第4期25卷 1355-1358页

作者： w. Marques jr. Departamento de Fisica Universidade Federal do Parana Calxa Postal 19044 81531-990 Curitiba Brazil

we analyse the problem concerning the propagation of sound waves in gases by using the modified hydrodynamic theory proposed recently by Brenner for single-component fluids. The modifications introduced by Brenner are based on his proposal that the translational momentum in fluid motion is not given by the mass flux. Comparison of the sound propagation results derived from Brenner＇s theory with available experimental data for monatomic gases shows that this modified continuum theory is unable to describe the acoustic measurements not even in the low-frequency limit, a result that from our point of view makes Brenner＇s proposal questionable.

关键词： Modification Classical Navier-stokes Equations Able

Emerging complexity and new roles for the RIG-I-like receptors in innate antiviral immunity

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Virologica sinica 2015年第3期30卷 163-173页

作者： John s.Errett Michael Gale jr. Center for Innate Immunity and Immune Disease Department of Immunology School of Medicine University of Washington

Innate immunity is critical for the control of virus infection and operates to restrict viral susceptibility and direct antiviral immunity for protection from acute or chronic viral-associated diseases including cancer. RIG-I like receptors(RLRs) are cytosolic RNA helicases that function as pathogen recognition receptors to detect RNA pathogen associated molecular patterns(PAMPs) of virus infection. The RLRs include RIG-I, MDA5, and LGP2. They function to recognize and bind to PAMP motifs.w.thin viral RNA in a process that directs the RLR to trigger downstream signaling cascades that induce innate immunity that controls viral replication and spread. Products of RLR signaling also serve to modulate the adaptive immune response to infection. Recent studies have additionally connected RLRs to signaling cascades that impart inflammatory and apoptotic responses to virus infection. Viral evasion of RLR signaling supports viral outgrowth and pathogenesis, including the onset of viral-associated cancer.

关键词： RIG-I MDA5 pattern recognition receptor pathogen associated molecular pattern innate immunity virus infection

Fuel and vegetation changes in southwestern, unburned portions of Great smoky Mountains National Park, UsA, 2003-2019

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Journal of Forestry Research 2022年第5期33卷 1459-1470页

作者： T.Adam coates w.Mark Ford Department of Forest Resources and Environmental Conservation Virginia Polytechnic Institute and State UniversityBlacksburgVA 24061USA U.s.Geological survey Virginia Cooperative Fish and Wildlife Research UnitDepartment of Fisheries and Wildlife ConservationVirginia Polytechnic Institute and State UniversityBlacksburgVA 24061USA

Overstory basal area,ericaceous shrub cover(Kalmia latifolia *** Rhododendron maximum L.),and fuels(i.e.,woody fuel loads and depths and O Horizon thickness) were assessed within Great smoky Mountains National Park,UsA,in *** to recent wildfire activity within the southern Appalachian Mountain region(including Great smoky Mountains National Park),the potential spread and expansion of ericaceous shrubs,and the impacts of the hemlock woolly adelgid(Adelges tsugae Annand) on eastern hemlock(Tsuga canadensis(L.) Carrière),these same ecosystem components.w.re again assessed in *** and moisture regime(xeric,intermediate,and mesic) were included in this assessment as potential influential *** evaluation of repeated measurements from 40 plots suggested that O Horizon thickness did not change significantly over the 16-year period,but increased as elevation increased,and moisture regime(xeric O Horizon thickness> mesic O Horizon thickness) was a significant,related *** sum of 1-,10-,and 100-h fuel loads(fuels less sed,whereas.w.ody fuel depth decreased over the16-year *** significant changes in 1000-h fuel lo ads(>7.6 cm diameter),total woody fuel loads,ericaceous shrub cover,total basal area,or live *** basal area were *** *** basal area decreased with increasing ***,standing *** basal area increased from 2003-2019,and that increase was most pronounced as elevation increased on xeric and intermediate ***,we found that:*** increases in total woody fuel loads and ericaceous shrub cover were not present;and *** and moisture regime were most related to observed changes in vegetation and fuel condition.

关键词： Eastern hemlock Hemlock woolly adelgid Mountain laurel Rhododendron

A Review on Cooperative Robotic Arms.w.th Mobile or Drones Bases

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International Journal of Automation and computing 2021年第4期18卷 536-555页

作者： Larona Pitso Ramalepa Rodrigo s.Jamisola jr. Botswana International University of science and Technology Palapye 10071Botswana

This review paper focuses on cooperative robotic arms.w.th mobile or drone bases performing cooperative tasks. This is because cooperative robots are often used as risk-reduction tools to human life. For example, they are used to explore dangerous places such as minefields and disarm explosives. Drones can be used to perform tasks such as aerial photography, military and defense missions,agricultural surveys, etc. The bases of the cooperative robotic arms can be stationary, mobile(ground), or drones. Cooperative manipulators allow faster performance of assigned tasks because of the available "extra hand". Furthermore, a mobile base increases the reachable ground workspace of cooperative manipulators.w.ile a drone base drastically increases this.w.rkspace to include the aerial *** papers in this review are chosen to extensively cover a wide variety of cooperative manipulation tasks and industries that use *** cooperative manipulation, avoiding self-collision is one of the most important tasks to be performed. In addition, path planning and formation control can be challenging because of the increased number of components to be coordinated.

关键词： Cooperative arms mobile manipulator aerial manipulator mobile base drone base cooperative tasks

Fabrication and characterization of Cu–Zn–sn shape memory alloys via an electrodeposition–annealing route

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International Journal of Minerals,Metallurgy and Materials 2019年第11期26卷 1436-1449页

作者： Richard Espiritu Alberto Amorsolo jr. Department of Mining Metallurgical and Materials Engineering University of the Philippines Diliman

Cu–Zn–sn shape memory alloys(sMAs.w.th an average composition of 56.0 at%,36.1 at%,and 7.9 at%for Cu,Zn,and sn,respectively,were successfully fabricated via an electrodeposition–annealing *** produced sMAs.w.re assessed for shape memory response in terms of percent displacement(martensite phase recovery)by subjecting the ternary alloys to flame tests and subsequently characterizing them via differential scanning calorimetry(DsC),optical microscopy,scanning electron microscopy in conjunction with energy-dispersive spectroscopy(sEM-EDs),and X-ray diffraction(XRD)*** flame tests showed that the highest displacement was ca.93%,with average austenite and martensitic start transformation temperature of 225°C and 222°C,*** analysis revealed that the intermetallic phases responsible for the observed shape memory properties have substitutional Zn in the lattice occupied by Cu and sn,leading to the formation of Cu(Zn,sn)and Cu6(Zn,sn)5 *** formation of these variants.w.s attributed to the faster interdiffusion of Cu into sn,driven by an activation energy of 34.82 kJ·mol^-*** cycles of repeated torching–annealing revealed an essentially constant shape memory response,suggesting that the fabricated sMAs.w.re consistent and sufficiently reliable for their intended service application.

关键词： electrodeposition annealing intermetallics martensitic transformation shape memory alloy

Investigation of normal,lateral,and oblique impact of microscale projectiles into unidirectional glass/epoxy composites

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Defence Technology（防务技术） 2022年第11期18卷 1960-1978页

作者： Christopher s.Meyer Isabel G.Catugas John w.Gillespie jr. Bazle Z.Gama Haque University of Delaware Center for Composite Materials(UD-CCM) 101 Academy StreetNewarkDE19716USA

spacesuits and spacecraft must endure high velocity impacts from micrometeoroids. This.w.rk considers the impact of 100 μm diameter projectiles into composite targets at velocities from 0.5 km/s to 2 km/*** work begins by presenting an energy-based theoretical model relating depth of penetration(Do P)and impact force to impact velocity, characteristic time, and threshold velocity and force. Next, this.w.rk compares numerical simulations of normal impact on composites to the theoretical model. Numerical simulations are conducted with Ls-DYNA and the well-known composite model, MAT-162. The numerical models consider unidirectional s2-glass fiber reinforced sC-15 epoxy composite laminates. The numerical model shows good correlation with the theoretical model. The numerical model also investigates lateral impact, parallel to the fiber direction, and oblique impact at angles from 30°to 82.5°.This.w.rk decomposes oblique impact into normal and lateral components, and compares them with normal and lateral impact results. The results show good correlation of the normal component of oblique results.w.th the theoretical model. This numerical and theoretical study focuses on Do P, velocity, and penetration resistance force as functions of time. The theoretical model and numerical simulations are used to determine new Do P parameters: characteristic time of depth of penetration and threshold impact velocity. These models are a first step in developing the capability to predict Do P for oblique,microscale, high-speed impact on composite materials.

关键词： Microscale Hypervelocity impact Composites Erosion Penetration

Thermodynamic Feedback between Clouds and the Ocean surface Mixed Layer

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Advances in Atmospheric sciences 1990年第1期7卷 1-10页

作者： P.C.Chu Roland w.Garwood jr. Department of Oceanography. Naval Postgraduate school Monterey CA 93943 U.S.A.Department of Oceanography. Naval Postgraduate School Monterey CA 93943 U.S.A.

A cloud-ocean planetary boundary layer (OPBL) feedback mechanism is presented and tested in this paper. water vapor, evaporated from the ocean surface or transported by the large-scale air flow, often forms convective clouds under a conditionally unstable lapse rate. The variable cloud cover and rainfall may have positive and negative feedback with the ocean mixed layer temperature and salinity structure. The coupling of the simplified Kuo's (1965) cumulus cloud model to the Kraus-Turner's (1967) ocean mixed layer model shows the existence of this feedback mechanism. The theory also predicts the generation of low frequency oscillation in the atmosphere and oceans.

关键词： Cl Feedback Thermodynamic Feedback between Clouds and the Ocean surface Mixed Layer

THE NATURAL LAw FOUNDATION OF THE MARKET

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Frontiers of Law in China-selected Publications from Chinese Universities 2020年第4期15卷 409-430页

作者： GUO Rui John s.Baker,jr. Harvard Law school CambridgeMAUnited States school of Law Renmin University of ChinaBeijing 100872China University of London LondonUK The Center for the Constitution Georgetown University Law CenterWashington D.C.USA Louisiana state University Law Center Baton RougeLouisiana 70803USA

In answering three important questions related to natural law,this paper offers a coherent explanation of the *** argue that the market,rather than a mechanism that simply serves narrow self-interests,finds its legitimacy in the ethical origins of the market *** need for law to support and sustain the market,including by imposing necessary limits on the freedom of the market players,flows from those ethical origins.

关键词： natural law market regulation the principle of subsidiarity

Cenozoic reactivation along the Late Triassic Ganzi-Litang suture,eastern Tibetan Plateau

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Geoscience Frontiers 2020年第3期11卷 1069-1080页

作者： w.T.Jackson jr. D.M.Robinson A.L.weislogel X.Jian Department of Earth sciences University of South AlabamaMobileAL36688USA Department of Geological sciences and Center for sedimentary Basin studies The University of AlabamaTuscaloosaAL35487USA Department of Geography and Geology West Virginia UniversityMorgantownWV26506USA state Key Laboratory of Marine Environmental science College of Ocean and Earth SciencesXiamen UniversityXiamen 361102China

The spatial-temporal development of Cenozoic reactivation along Mesozoic suture zones in the Tibetan Plateau are first-order parameters needed for assessing models of plateau *** Ganzi-Litang suture,in the eastern Tibetan Plateau,developed in the Late Triassic because of subduction and closure along the eastern branch of the Paleo-Tethys *** the city of Litang,the Ganzi-Litang suture is defined by a melange sequence with faultbound,synorogenic nonmarine strata along the western and eastern flanks,suggesting post-Triassic structural *** present detrital zircon U-Pb geochronology and field data to determine the timing and style of reactivation along the Ganzi-Litang suture,as.w.ll as sedimentary provenance of nonmarine strata.A reverse fault placing melange rock on top of nonmarine strata along the eastern flank of the Ganzi-Litang suture indicates a contractional deformational regime during *** clast counts indicate a local sediment source of recycled Ganzi-Litang suture and Yidun terrane *** zircons indicate a localized provenance consisting of recycled material from Triassic Yidun Arc plutons and Triassic Yidun Group turbidite rock.A weighted mean average of Cenozoic zircon grains(n=10) establishes a maximum depositional age of41.5 ± 1.2 Ma for nonmarine strata in the Ganzi-Litang *** interpret the maximum depositional age of the nonmarine strata to represent the upper-limit for structural reactivation along the Ganzi-Litang suture while undeformed Neogene strata in the suture zone represent the lower-limit;thereby bracketing structural reactivation from ca.42-25 *** results provide enhanced spatial-temporal resolution for Cenozoic deformation in the eastern Tibetan Plateau.

关键词： Nonmarine strata Yidun terrane Tibetan plateau Zircon suture zone Reactivation