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High Power Laser Science and Engineering 2015年第3期3卷 59-65页

作者： T.Nagayama r.c.Mancini D.Mayes r.Tommasini r.Florido Physics Department University of Nevada Lawrence Livermore National Laboratory Departamento de Física Universidad de Las Palmas de Gran Canaria

Temperature and density asymmetry diagnosis is critical to advance inertial confinement fusion(IcF) science. A multimonochromatic x-ray imager, MMI, records the spectral signature from an IcF implosion core with time resolution, 2D spatial resolution and spectral resolution. While narrow-band images and 2D space-resolved spectra from the MMI data constrain the temperature and the density spatial structure of the core, the accuracy of the images and the spectra highly depends on the quality of the MMI data and the processing tools. Here, we synthetically investigate the criterion for.reliable MMI diagnostics and its effects on the accuracy of the reconstructed images. The pinhole array tilt determines the object spatial sampling efficiency and the minimum reconstruction width, w. When the spectral width associated with w is significantly narrower than the spectral linewidth, the line images reconstructed from the MMI data become reliable. The MMI setup has to be optimized for.every application to meet this criterion for.reliable IcF diagnostics.

关键词： high power laser inertial confinement fusion monochromatic imager x-ray diagnostics

A New Approach to Energy Integral for.Investigation of Dust-Ion Acoustic(DIA)Waves in Multi-component Plasmas with Quantum Effects in Inertia Less Electrons

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communications in Theoretical Physics 2015年第6期63卷 761-768页

作者： B.c.Kalita r.Kalita Department of Mathematics Gauhati University

Dust-ion acoustic waves are investigated in this model of plasma consisting of negatively charged dusts, cold ions and inertia less quantum effected electrons with the help of a typical energy integral. In this case, a new technique is applied for.ulating a differential equation to establish the energy integral in case of multi-component plasmas which is not possible in general. Dust-ion acoustic （DIA） compressive and rarefactive, supersonic and subsonic solitons of various amplitudes are established. The consideration of smaller order nonlinearity in support of the newly established quantum plasma model is observed to generate small amplitude solitons at the decrease of Mach number. The growths of soliton amplitudes and potential depths are found more sensitive to the density of quantum electrons. The small density ratio r（= 1 - f） with a little quantized electrons supplemented by the dust charges Zu and the in-deterministic new quantum parameter c2 are found responsible to finally support the generation of small amplitude solitons admissible for.the model.

关键词： dust-acoustic solitary waves quantum effects

Analysis of Differences in Productivity,Profitability and Soil Fertility Between Organic and conventional cropping Systems in the Tropics and Sub-tropics

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Journal of Integrative Agriculture 2014年第10期13卷 2299-2310页

作者： Te Pas c M rees r M School of GeoSciences University of Edinburgh carbon Management centre Scotland's Rural College

Organic farming aims to stimulate soil fertility by avoiding the use of synthetic fertiliser inputs, relying instead on locally available natural resources. It is regarded by many as a sustainable alternative to conventional fanning because it ensures higher biodiversity, restricts environmental pollution, prevents land degradation and is easy to apply for.smallholder and subsistence farmers. Although widely practiced and studied in temperate regions, little is known about the potential overall benefits of organic farming in the tropics and subtropics. This paper addresses this gap by undertaking an analysis of the differences between organic and conventional agriculture in the tropics and sub-tropics based on an extensive literature review including 88 papers with 458 data pairs. The comparison is based on three main indicators： yield, gross margin and soil organic carbon （SOc）. The differences between the organic and conventional systems for.each of these main indicators is represented by the ratio of the value of the indicator in the organic system divided by the corresponding value in the conventional system. This was initially calculated for.each data pair individually, and grouped by a variety of explanatory factors, such as precipitation, human development level, soil texture, crop type, organic input type, time after conversion and certification. The results demonstrate that under organic management, yields were on average 26% higher, gross margins 51% higher and soil organic carbon 53% higher than under conventional management. The highest yield increases in organic cropping systems were achieved in the least developed countries, in arid regions and on coarse soils. for.gross margins, certification was the main reason for.differences between organic and conventional systems. certified farmers, mostly located in developed countries, receive significantly higher prices. Furthermore, organic farming in the driest regions results in higher profits than in other

关键词： organic farming conventional fanning tropics subtropics carbon sequestration yield soil quality soil organic carbon

Histomorphological and Histochemical Alterations Following Short-term Inhalation Exposure to Sulfur Mustard on Visceral Organs of Mice

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Biomedical and Environmental Sciences 1999年第3期12卷 201-213页

作者： S·c·PANT r·VIJAYarAGHAVAN DivisionofpharmacologyandTcxicology DefenceResearchandDevelopmentEstablishmentJhansiRoadGwalior－4740

Toxic effects of inhaled sulfur mustard (SM) on the histology of visceral organs was investigaed by exposing mice to 84. 6mg/m3 for.1h duration, using controlled single exposure conditions. A progressive fall in body weight from third day onwards was noticed. Light microscopic examination of the pulmonary tissue of these animals at 6 h post exposure revealed that the tracheobronchial epithelium remained intact, but was infiltrated by inflammatory cells. By 24 h post exposure, the mucosecretory cells were destroyed. The indanunatory reaction was maximum at 48 h. By 7th day post exposure there was swelling and vacuolation of lung parenchymal cells and thrombi for.ation. In addition SM caused congestion and hemorrhage at alveolar level. SM also caused granulovacuolar degeneration with perinuclear clumping of the cytopasm of hepatocytes and renal parenchymal cells. renallesions were chazacterized by congestion and hemorrhage. Among visceral tissues, maximum atrophywas observed in spleen. Distribution of lesions increased with post exposure period. The maximum lesions were observed at 7th day post-exposure.

关键词： Animals Dermatologic Agents Female Hemorrhage Inhalation Exposure Kidney Lung Mice Mustard Gas Time Factors Weight Loss

Effects of thermal radiation on MHD viscous fluid flow and heat transfer over nonlinear shrinking porous sheet

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Applied Mathematics and Mechanics(English Edition) 2011年第6期32卷 677-688页

作者： G.c.SHIT r.HALDar Department of Mathematics Jadavpur University

This paper investigates the effects of thermal radiation on the magnetohy- drodynamic （MHD） flow and heat transfer over a nonlinear shrinking porous sheet. The surface velocity of the shrinking sheet and the transverse magnetic field are assumed to vary as a power function of the distance from the origin. The temperature dependent viscosity and the thermal conductivity are also assumed to vary as an inverse function and a linear function of the temperature, respectively. A generalized similarity transfor. mation is used to reduce the governing partial differential equations to their nonlinear coupled ordinary differential equations, and is solved numerically by using a finite difference scheme. The numerical results concern with the velocity and temperature profiles as well as the local skin-friction coefficient and the rate of the heat transfer at the porous sheet for.different values of several physical parameters of interest.

关键词： thermal radiation shrinking sheet variable viscosity variable thermalconductivity

Evaluation of Dry Sliding Wear Behaviour of Plasma Transferred arc Hardfaced Stainless Steel

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Journal of Iron and Steel research International 2009年第4期16卷 49-54页

作者： c S ramachandran V Balasubramanian r Varahamoorthy centre for.Materials Joining and research(cEMAJOr) Department of Manufacturing EngineeringAnnamalai University

The effects of different experimental conditions on the dry sliding wear behavior of stainless steel surface produced by plasma transferred arc （PTA） hardfacing process were studied. The wear test was conducted in a pinon-roller wear testing machine, at constant sliding distance of 1 kin. Mathematical models were developed to estimate wear rate incorporating with rotational speed, applied load and roller hardness using statistical tools such as design of experiments, regression analysis and analysis of variance. It is found that the wear resistance of the PTA hardfaced stainless steel surface is better than that of the carbon steel substrate.

关键词： dry sliding wear plasma transferred arc hardfacing carbon steel stainless steel variance analysis experimental design

Effects of chemical reactions on MHD micropolar fluid flow past a vertical plate in slip-flow regime

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Applied Mathematics and Mechanics(English Edition) 2008年第9期29卷 1179-1194页

作者： r.c.chaudhary Abhay Kumar Jha Department of Mathematics University of Rajasthan

Heat and mass transfer effects on the unsteady flow of a micropolar fluid through a porous medium bounded by a semi-infinite vertical plate in a slip-flow regime are studied taking into account a homogeneous chemical reaction of the first order. A unifor. magnetic field acts perpendicular to the porous surface absorb micropolar fluid with a suction velocity varying with time. The free stream velocity follows an exponentially increasing or decreasing small perturbation law. Using the approximate method, the expressions for.the velocity microrotation, temperature, and concentration are obtained. Futher, the results of the skin friction coefficient, the couple stress coefficient, and the rate of heat and mass transfer at the wall are presented with various values of fluid properties and flow conditions.

关键词： micropolar fluid microrotation chemical reaction slip-flow magnetohy-drodynamics heat and mass transfer

Liquid Film on Unsteady Stretching Sheet with General Surface Temperature and Viscous Dissipation

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chinese Physics Letters 2010年第11期27卷 5-8页

作者： r. c. Aziz I. Hashim Faculty of Science and Technology Open University Malaysia 50480 Kuala Lumpur Malaysia centre for.Modelling and Data Analysis School of Mathematical Sciences Universiti Kebangsaan Malaysia 43600 UKM Bangi Selangor Malaysia

We study the effects of viscous dissipation on flow and heat transfer in a thin liquid film on an unsteady stretching sheet. A general surface temperature is taken into consideration. The velocity and temperature fields are solved using the homotopy analysis method. The results show that the increasing values of the Eckert number can increase temperature distribution and the heat transfer rate.

关键词： Soft matter liquids and polymers Surfaces interfaces and thin films

riparian Vegetation Dynamics Across Two Different Landscapes Along the river cauvery in the Kodagu region of Western Ghats

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Journal of Mountain Science 2012年第3期9卷 351-361页

作者： c.SUNIL r.K.SOMASHEKar B.c.NAGarAJA Department of Environmental Science Bangalore UniversityIndia

Decades of commercial planting and other anthropogenic processes are posing a threat to the riparian landscapes of the cauvery river basin, which supports a high floral diversity. Despite this, the habitats in the upstream sections of the river cauvery are still intact, as they are located in sacred groves. To understand the dynamism of riparian for.sts exposed to anthropogenic pressures, the upstream stretch of cauvery extending from Kushalanagara to Talacauvery （~102 km） was categorized into two landscapes： agro ecosystem and sacred （i.e. preserved）. The tree species were sampled using belt transects at 5 km intervals and the regeneration status of endemic species assessed using quadrats. A total of 128 species belonging to 47 families, and representing 1,590 individuals, was observed. Amongst them, 65% of unique species were exclusive to sacred landscapes. A rarefaction plot confirmed higher species richness for.the sacred compared to the agro ecosystem landscapes, and diversity indices with more evenness in distribution were evident in sacred landscapes. A significant loss of endemic tree species in the agro ecosystem landscapes was found. Overall, this study demonstrates that an intense biotic pressure in terms of plantations and other anthropogenic activities have altered the species composition of the riparian zone in non-sacred areas. A permanent policy implication is required for.the conservation of riparian buffers to avoid further ecosystem degradation and loss of biodiversity.

关键词： Western Ghats riparian vegetation cauvery river Sacred grove Agro ecosystemlandscape Diversity indices Endemic species.

Processing of rare earth concentrates

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rare Metals 2005年第3期24卷 210-215页

作者： Pamela Alex r.c. Hubli A.K. Suri Material Processing Division Bhabha Atomic Research Centre Trombay Mumbai-400085 IndiaMaterial Processing Division Bhabha Atomic Research Centre Trombay Mumbai-400085 IndiaMaterial Processing Division Bhabha Atomic Research Centre Trombay Mumbai-400085 India

The paper describes process details for.extraction of rare earths from an intermediate grade concentrate of Madhya Pradesh region in India and a South African slag. The xenodme concentrate obtained from the for.er place was an intermediate grade （47%） rare earth phosphate containing both monazite and xenotime. The South African slag was a low-grade waste product typically containing only 4% of rare earths. The rare earth resource concentrates have been treated individually by different methods such as alkali fusion and alkali leaching to convert them into their mixed oxides. Both types of materials have been processed and greater than 98% solubilization of metal values has been achieved in the intermediate grade xenotime and 80% from the South African slag. The residue of xenotime hydroxide has been washed thoroughly to collect the sodium phosphate, as by-product and the slurry pH have been adjusted to separate rare earths from thorium effectively. Other impurities such as uranium and iron have been removed by precipitation of rare earths by oxalic acid. It has been possible to recover 〉95% yttrium along with other rare earth oxides.

关键词： xenotime slag fusion leaching calcining solubilization