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Conceptual design of an experiment to study dust destruction by astrophysical shock waves

High Power Laser Science and engineering 2018年第3期6卷 9-14页

作者： M. j.-e. Manuel T. Temim e. Dwek A. M. Angulo e X. Belancourt R. e Drake C. C. Kuranz M. j. MacDonald B. A. Remington General Atomics 3550 General Atomics Court San Diego CA 92121 USA Space Telescope Science Institute 3700 San Martin Drive Baltimore MD 21218 USA Observational Cosmology Lab Code 665 NASA Goddard Space Flight Center Greenbelt MD 20771 USA Climate and Space Science and engineering University of Michigan Ann Arbor M148109 USA Department of Physics University of California Berkeley CA 94720 USA Lawrence Livermore National Laboratory Livermore CA 94450 USA

A novel laboratory experimental design is described that will investigate the processing of dust grains in astrophysical shocks. Dust is a ubiquitous ingredient in the interstellar medium(ISM) of galaxies; however, its evolutionary cycle is still poorly understood. especially shrouded in mystery is the efficiency of grain destruction by astrophysical shocks generated by expanding supernova remnants. While the evolution of these remnants is fairly well understood, the grain destruction efficiency in these shocks is largely unknown. The experiments described herein will fill this knowledge gap by studying the dust destruction efficiencies for shock velocities in the range ～10–30 km/s(μm/ns), at which most of the grain destruction and processing in the ISM takes place. The experiments focus on the study of grain–grain collisions by accelerating small(～1 μm) dust particles into a large(～5–10 μm diameter) population; this simulates the astrophysical system well in that the more numerous, small grains impact and collide with the large population. Facilities that combine the versatility of high-power optical lasers with the diagnostic capabilities of X-ray free-electron lasers, e.g., the Matter in extreme Conditions instrument at the SLAC National Accelerator Laboratory, provide an ideal laboratory environment to create and diagnose dust destruction by astrophysically relevant shocks at the micron scale.

关键词： laboratory astrophysics shock waves dust destruction

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Conservative Finite-Difference Scheme for High-Frequency Acoustic Waves Propagating at an Interface Between TwoMedia

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Communications in Computational Physics 2012年第2期11卷 351-366页

作者： j.Staudacher e.Savin ONeRA–The French Aerospace Lab F-92322 ChatillonFrance

This paper is an introduction to a conservative,positive numerical scheme which takes into account the phenomena of reflection and transmission of high frequency acoustic waves at a straight interface between two homogeneous *** forms of the interpolation coefficients for reflected and transmitted wave vectors on a two-dimensional uniform grid are *** propagation model is a Liouville transport equation solved in phase space.

关键词： Acoustics high-frequency Liouville equation energy conservation reflection transmission

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A linear regression model (LRM) for groundwater chemistry in and around the Vaniyambadi industrial area, Tamil Nadu, India

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Chinese journal Of Geochemistry 2013年第1期32卷 19-26页

作者： Sajil Kumar P.j. Davis Delson P. Vernon j.G. james e.j. Brandenburg Technical University Cottbus-03046 Germany ITALCONSULT Riyadh-11421 Saudi Arabia Budapest University of Technology and economics (BMe) Budapest-Pf. 91 H-152 Hungary Water Institute Karunya UniversityCoimbatore-641114 India

A linear regression model in conjunction with cluster analysis was applied to the groundwater quality parameters for the Vaniyambadi industrial area, Tamil Nadu, India. These physico-chemical parameters were collected from 25 wells by intensive groundwater sampling conducted during january 2010. All the major ions, pH and electrical conductivity were analyzed. The abundances of cations were in the order of Na e of anions were in the order of Cl espectively. This was in agreement with the water types, Na-Cl and Na-Ca-HCO3, determined by the Piper plot. High concentrations of the ions Na, Cl and SO4 were recorded near the tanneries that operate within the study area. While the elevated concentrations of HCO3 and F were observed away from the tanneries. This peculiar hydrochemical behaviour suggests that the chemistry of water is predominantly influenced by tannery effluents and weathering of silicate minerals. Results of the linear regression model yielded 11 regression equations for the 5 most correlated parameters. A dendrogram from the cluster analysis showed 2 major clusters representing the influence of tanneries and geological formations in the study area, which confirmed the results of major ion chemistry.

关键词：线性回归模型地下水化学工业区印度 LRM 聚类分析物理化学参数研究区域

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An Awareness-Adoption Matrix for Strategic Decision Making in Agricultural Development Projects: A Case Study in Yunnan Province, China

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journal of Integrative Agriculture 2009年第9期8卷 1112-1119页

作者： M Subedi T j Hocking M A Fullen A R McCrea e Milne D j Mitchell School of Applied Sciences The University of Wolverhampton Wolverhampton WV1 1LY UK Department of Geography University of Leicester Leicester LE1 7RH UK

Significant achievements have been made in generating sustainable agricultural technologies in developing countries. Usually, these new technologies have been more effective in increasing production and productivity than existing technologies. However, many new technologies considered ‘effective’ have not been successful in alleviating the associated sustainability problems, due to poor adoption by targeted users. Success of any novel technical intervention should be judged on the basis of how widespread adoption is in the target area by targeted users. In this context, a case study identified the factors affecting farmers’ adoption of improved technologies extended by an agricultural development project in a rural Village in Yunnan Province, China. Initial adoption/adaptation of project technologies was influenced by farmers’ awareness of the technology. Farmers were more aware of polythene mulch, contour cultivation, intercropping and tree planting technologies than others. This led to a comparatively high initial uptake of polythene mulch, contour cultivation, sweet chestnut, and intercropping technologies. Farmers had inadequate knowledge about some Project technologies, the adoption of which was particularly low. This reveals the need for increasing farmers’ awareness about the rationale for Project technologies to achieve greater adoption/adaptation of project technologies by farmers over wider areas. Farmers’ testing of the technology leads to better adoption/adaptation compared to mere awareness. However, considerable time and resources are required for testing/trying technologies. This justifies the usefulness of comparatively quick and less resource demanding options for awareness creation. Development of effective cropping technologies is important for sustainable agricultural development. The success of any agricultural development project, especially in terms of improving sustainability, depends on how widely those improved technologies are adopted/adap

关键词： awareness-adoption matrix sustainable agriculture China

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Weak Continuity of Riemann Integrable Functions in Lebesgue-Bochner Spaces

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Acta Mathematica Sinica,english Series 2010年第2期26卷 241-248页

作者： j.M.CALABUIG j.RODRíGUeZ e.A.SNCHeZ-PReZ Instituto Universitario de Matemlica Pura y Aplicada Universidad Politcnica de Valencia

In general, Banach space-valued Riemann integrable functions defined on [0, 1] （equipped with the Lebesgue measure） need not be weakly continuous almost everywhere. A Banach space is said to have the weak Lebesgue property if every Riemann integrable function taking values in it is weakly continuous almost everywhere. In this paper we discuss this property for the Banach space LX^1 of all Bochner integrable functions from [0, 1] to the Banach space X. We show that LX^1 has the weak Lebesgue property whenever X has the Radon-Nikodym property and X＊ is separable. This generalizes the result by Chonghu Wang and Kang Wan [Rocky Mountain j. Math., 31（2）, 697-703 （2001）] that L^1[0, 1] has the weak Lebesgue property.

关键词： Riemann integral Bochner integral Lebesgue-Bochner space weak Lebesgue property

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Helicity Amplitude Analysis of Z_c(3900)~± in e^+e^- →π^+π^-j/ψ

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Chinese Physics Letters 2016年第6期33卷 9-11页

作者：平荣刚 j.G.Messchendorp 苑长征 Institute of High energy Physics Chinese Academy of Sciences KVI-CART University of Groningen

It is crucial to determine the spin and parity （jR） of Zc（3900）＋ for understanding its structure. We perform a helicity amplitude analysis on Zc（3900）＋ in the process e＋e- →π＋π-j/φ＊ with the hypotheses jP = 0-, 1＋, 1-, 2＋ and 2-. To estimate the significance of jP = 1＋ over other hypotheses, we perform a Monte Carlo simulation study, and we also discuss the prospect of measuring the spin parity in the future experiment with a large data sample.

关键词： of on is Helicity Amplitude Analysis of Z_c in e for that

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On environmental threats to male infertility

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Asian journal of Andrology 2013年第2期15卷 199-200,I0005页

作者： Allen j Wilcox jens Peter e Bonde epidemiology Branch National Institute of Environmental Health Sciences Durham NC 27709-2233 USA Department of Occupational and environmental Medicine University Hospital of Copenhagen Copenhagen NV DK-2400 Denmark

The possibility that environmental pollutants damage human fertility is a topic of both public concern and scientific interest. The effect of environmental factors on male fertility （semen parameters） has been a special focus, stimulated in part by the dramatic damage inflicted by the pcstlcide DBCP on testicular function. extensive searches for testicular toxicants （in particular, the proposed effects of endocrine-disrupting compounds through fetal exposure） have produced little hard evidence of impairment in humans. This scarcity of evidence may reflect the difficultles of studying human fertility. Future fertifity studies should consider the wide spectrum of environmental exposures that plausibly affect reproduction.

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Skeletal Blood Flow in Bone Repair and Maintenance

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Bone Research 2013年第4期1卷 311-322页

作者： Ryan e.Tomlinson Matthew j.Silva Department of Orthopaedic Surgery Washington University in St.Louis Musculoskeletal Research Center Washington University in St.Louis

Bone is a highly vascularized tissue, although this aspect of bone is often overlooked. In this article, the importance of blood flow in bone repair and regeneration will be reviewed. First, the skeletal vascular anato- my, with an emphasis on long bones, the distinct mechanisms for vascularizing bone tissue, and methods for remodeling existing vasculature are discussed. Next, techniques for quantifying bone blood flow are briefly summarized. Finally, the body of experimental work that demonstrates the role of bone blood flow in fracture healing, distraction osteogenesis, osteoporosis, disuse osteopenia, and bone grafting is examined. These results illustrate that adequate bone blood flow is an important clinical consideration, particularly during bone regeneration and in at-risk patient groups.

关键词： blood flow angiogenesis vascular remodeling fracture bone repair

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Near-Net-Shaped Objects of Re123 Superconductors byInfiltration Processing

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Tsinghua Science and Technology 2003年第3期8卷 292-306页

作者： e.S.Reddy G.j.Schmitz ACCeSS Materials and Processes D-52056 AachenGermanyACCESS Materials and ProcessesD-52056 AachenGermany

The fabrication of near-net-shaped objects of Re123 superconductors by 'infiltration processing' is discussed. Near-net-shape processing involves the infiltration of preshaped porous green bodies of either 211 or yttria phases by liquids containing barium cuprates and copper oxides followed by a controlled peritectic solidification. The process yields poly- and also single-crystalline superconducting objects with a shrinkage of less than half of one percent of the green bodies. The preservation of the initial structure of the green bodies results in fabrication of Re 123 in a wide variety of dimensions and complex shapes. The demonstrated products include bulk components like cylinders, single domain thick films on a variety of substrates, freestanding fabrics and open porous superconducting foams. This paper presents a comprehensive description of the infiltration processing technique and the resulting microstructures of the superconducting bodies. The advantages of this technique and practical applications of the processed superconducting structures are highlighted.

关键词： infiltration processing near-net shape shaping joining single domain crystal growth thick films foams applications

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Intrinsically photosensitive retinal ganglion cells

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Science China(Life Sciences) 2010年第1期53卷 58-67页

作者： Gary e.PICKARD Patricia j.SOLLARS School of Veterinary Medicine and Biomedical Sciences University of Nebraska

A new mammalian photoreceptor was recently discovered to reside in the ganglion cell layer of the inner *** intrinsically photosensitive retinal ganglion cells(ipRGCs) express a photopigment,melanopsin,that confers upon them the ability to respond to light in the absence of all rod and cone photoreceptor *** relatively few in number,ipRGCs extend their dendrites across large expanses of the retina making them ideally suited to function as irradiance detectors to assess changes in ambient light *** in ipRGCs appears to be mediated by transient receptor potential channels more closely resembling the phototransduction cascade of invertebrate rather than vertebrate *** convey irradiance information centrally via the optic nerve to influence several *** are the primary retinal input to the hypothalamic suprachiasmatic nucleus(SCN),a circadian oscillator and biological clock,and this input entrains the SCN to the day/night *** contribute irradiance signals that regulate pupil size and they also provide signals that interface with the autonomic nervous system to regulate rhythmic gene activity in major organs of the *** also provide excitatory drive to dopaminergic amacrine cells in the retina,providing a novel basis for the restructuring of retinal circuits by *** we review the ground-breaking discoveries,current progress and directions for future investigation.

关键词： melanopsin circadian rhythms suprachiasmatic nucleus retina pupillary light reflex

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