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Differentially Expressed Genes between Two Barley Cultivars Contrasting in Drought Tolerance

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分子植物育种 2007年第2期5卷 181-183页

作者： P.G. Guo　 M. Baum　 r.H. Li 　 S. Grando r.k. varshney　 J. Valkoun　 S. Ceccarelli　 A. Grane College of Life Science Guangzhou University Guangzhou 510006 China International Centre for Agricultural research in the Dry Areas （ICArDA） P.O. Box 5466 Aleppo Syria Institute of Plant Genetics and Crop Plant research （IPk） Gatersleben Germany

Drought tolerance is a key trait for increasing and stabilizing barley productivity in dry areas. A number of genes have been described that respond to drought at the transcriptional level (Seki et al., 2002; Cheong e... 详细信息

关键词：基因表达栽培品种干旱耐受性能

Tunnelling through weak and fragile rocks of Himalayas

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International Journal of Mining Science and Technology 2014年第6期24卷 783-790页

作者： Goel r.k. CSIr-Central Institute of Mining & Fuel research Regional CentreCBRI Campus Roorkee India

A considerable amount of tunnelling has been going on in India for various projects such as hydroelectric power, irrigation, roads and railways. Most of these projects are located in Himalayas, far away from the urban areas. Tunnelling through weak and jointed rock masses such as the one in the Himalayas is a challenging task for the planners, designers, engineers and geologists because of high overburden, thickly vegetated surface, weak, poor and fragile rocks and highly varying geology with the presence of numerous small and big shear zones, faults, etc. Due to these reasons, various tunnelling problems have been faced in the past and are still being encountered. Failures and the problems may be regarded as challenges and opportunities for generating new knowledge base and thereby increasing self-reliance in tunnelling. The experiences of Himalayan tunnelling through weak and fragile rocks covering varying and mixed geology, understanding on tunnelling in squeezing ground conditions and applicability of TBM in Himalayas are presented. It has also been highlighted that the probe holes planning, drilling and monitoring shall be followed seriously to reduce the geological surprises.

关键词： Varying geology Mixed geology Weak and fragile rocks Himalayan tunnelling Ground condition Squeezing

Effect of Post Heat Treatment on Corrosion resistance of Phytic Acid Conversion Coated Magnesium

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Journal of Materials Science & Technology 2013年第2期29卷 180-186页

作者： r.k. Gupta k. Mensah-Darkwa D. kumar Engineering research Center for revolutionizing Metallic Biomaterials (ErC-rMB) Department of Mechanical Engineering North Carolina A&T State University 1601 East Market Street Greensboro NC 27411 USA

An environment friendly chemical conversion coating for magnesium was obtained by using a phytic acid solution. The effect of post-coating 1heat treatment on the microstructures and corrosion properties of phytic acid conversion coated magnesium was investigated. It was observed that the microstructure and corrosion resistive properties were improved for the heat treated samples. The corrosion current density for bare magnesium, phytic acid conversion coated magnesium, and post-coating heat treated magnesium was calculated to be 2.48 ×10^-5, 1.18×10^-6, and 9.27 × 10^7 A/cm^2, respectively. The lowest corrosion current density for the heat treated sample indicated its highest corrosion resistive effect for the magnesium. The maximum corrosion protective nature of the heat treated sample was further confirmed by the largest value of impedance in electrochemical impedance spectroscopy studies.

关键词： Magnesium Phytic acid Corrosion Impedance spectroscopy Scanning electron microscopy

Geochemistry of groundwater, Markandeya river Basin, Belgaum district, karnataka State, India

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Chinese Journal Of Geochemistry 2011年第1期30卷 51-74页

作者： ravikumar P. Somashekar r.k. Department of Environmental Science Bangalore University Bangalore-560 056India

The Markandeya river Basin stretches geographically from 15o56′ to 16o08′ N latitude and 74o37′ to 74o58′ E longitude, positioned in the midst of Belgaum district, in the northern part of karnataka. The groundwater quality of 54 pre-monsoon samples in the Markandeya river Basin was evaluated for its suitability for drinking and irrigation purposes by estimating pH, EC, TDS, hardness and alkalinity besides major cations (Na+, k+, Ca2+, Mg2+) and anions (HCO3–, Cl–, SO42–, PO43-, F-, NO3–), boron, SAr, % Na, rSC, rSBC, chlorinity index, SSP, non-carbonate hardness, Potential Salinity, Permeability Index, kelley’s ratio, Magnesium hazard and Index of Base Exchange. Negative Index of Base Exchange indicates the chloro-alkaline disequilibrium in the study area and the majority of water samples fall in the rock dominance field based on Gibbs’ ratio. Permeability indices of classes I and II suggest suitability of groundwater for irrigation. Based on Cl, SO4, HCO3 concentrations, water samples can be classified as normal chloride (96.3%) and normal sulfate (94.4%) and normal bicarbonate (44.4%) water types.

关键词：水地球化学流域贝尔纳塔地下水水质碳酸盐硬度印度碳酸氢钠

Spectroscopic investigations and luminescence spectra of Sm3+ doped soda lime silicate glasses

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Journal of rare Earths 2009年第5期27卷 773-780页

作者： Y.k. Sharma S.S.L. Surana r.k. Singh Department of Physics Govt. Post Graduate College Rudrapur 263153 (U S Nagar) India Department of Physics J. N. V. University Jodhpur-342001 India Department of Physics Govt. Post Graduate College Rudrapur 263153 (U S Nagar) India

Sm3+ doped soda lime silicate glasses co-doped with As2O3 were prepared and characterised by measuring their absorption spectra in UV-VIS/NIr regions and luminescence spectra in the visible region. Judd-Ofelt intensity parameters, Ωλ, were evaluated from the measured intensities of the various absorption bands. Ωλ parameters of these glasses were compared with the Ωλ parameters of other reported Sm3+ glasses to study the bonding environment surrounding the Sm3+ in the present glasses. Presence of [AsO4]3– tetrahedra in the second coordination sphere around the central Sm3+ ion made these glasses less covalent as compared to other oxide glasses but the ratio Ω4/Ω6 of the 1.83 indicated them to be fairly stable. With the help of Ωλ parameters and luminescence data for various emission lines, radiative properties for different emission lines were calculated. The values of radiative properties indicated that 4G5/2→6H7/2 and 4G5/2→6H9/2 transitions responsible for orange luminescence might be used in the development of materials for LED's and other optical devices in the visible region.

关键词： rare earth glasses Judd-Ofelt theory absorption spectroscopy luminescence

Mechanically induced stiffening, thermally driven softening,and brittle nature of SiC

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Journal of Advanced Ceramics 2016年第1期5卷 13-34页

作者： Dinesh varshney Swarna SHrIYA Sanjay JAIN Meenu varshney r.k.ENATA School of Physics Vigyan Bhavan Devi Ahilya University Khandwa Road Campus Indore 452001 India Department of Physics M.B.Khalsa College Indore 452002 India Laboratoire de Physique Quantique et de Modélisation Mathématique(LPQ3M) Département de TechnologieUniversité de Mascara Mascara 29000 Algeria

An effective interionic potential calculation with long range Coulomb, charge transfer interaction, covalency effect, short range overlap repulsion extended, van der Waals interaction, and zero point energy effect is implemented to investigate the pressure dependent structural phase transition (ZnS-type (B3) to NaCl-type (B1) structure), and mechanical, elastic, and thermodynamic properties of silicon carbide (SiC). Both charge transfer interaction and covalency effect are important in revealing the pressure induced structural stability, Cauchy discrepancy, anisotropy factor, melting temperature, shear modulus, Young’s modulus, and Grüneisen parameter. We also present the results for the temperature dependent behaviors of normalized volume, hardness, heat capacity, and thermal expansion coefficient. SiC is mechanically stiffened and thermally softened as inferred from pressure (temperature) dependent elastic constant’s behavior. The Pugh’s ratio ∅ = B T / G H, the Poisson’s ratio v, and the Cauchy’s pressure C 12–C 44 for SiC ceramic confirm its brittle nature.

关键词： carbide computational techniques phase transition equation of state

A study of local amplification effect of soil layers on ground motion in the kathmandu Valley using microtremor analysis

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Earthquake Engineering and Engineering Vibration 2012年第2期11卷 257-268页

作者： Paudyal Y.r. Yatabe r. Bhandary N.P. Dahal r.k. Geo-disaster research Laboratory Graduate School of Science and EngineeringEhime UniversityEhimeMatsuyamaJapan

Past researchers have anticipated the occurrence of a great earthquake in the central Himalayas in the near *** may cause serious damage in the kathmandu Valley,which sits on an ancient lake bed zone,with lacustrine sediments of more than 500 m *** this study,the predominant frequency of ground motion is evaluated using the Horizontal-to-Vertical (H/V) spectral ratio technique and recordings of ambient *** results of the H/V ratio show two peaks in about 20 percent of the locations,which are distributed mainly in and around the center and northern part of the kathmandu *** predominant frequencies vary from 0.5 Hz to 8.9 Hz in the study area,whereas the second resonance fiequency varies from 4 Hz to 6 Hz in the center and northern part of the *** indicates that the center and northern part of the valley have a wide range of resonance frequency due to two levels of impedance contrast- one may be from the surface layer and the other may be from the layer *** two levels of resonance indicate the importance of considering the effects of surface and lower layers during the planning and designing of infrastructures in the kathmandu Valley.

关键词： microtremor predominant frequency resonance kathmandu Valley

Transmission Electron Microscopy Study of the Infrared Brazed High-strength Titanium Alloy

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Journal of Materials Science & Technology 2010年第4期26卷 311-316页

作者： Z.Y. Wu r.k. Shiue C.S. Chang Department of Materials Science and Engineering National Taiwan University Taipei 106 Taiwan China Engineered Materials Solutions 39 Perry Avenue MS 4-1 Attleboro MA 02703-2410 USA

The transmission electron microscopy was employed to investigate the microstructure of infrared brazed highstrength Ti alloy using the Ti-15Cu-15Ni filler metal. Coarse primary Ti2Ni and transformed β-Ti are observed in the 300 s brazed specimen. Blocky Ti2Ni and eutectoid Ti2Cu intermetallics are disappeared from the joint with increasing the brazing time to 1800 s. Both acicular α-Ti and retained β-Ti dominate the entire brazed joint.

关键词： Infrared Brazing Ti Ti-Cu-Ni filler Microstructure

Tailoring wind properties by various passive roughness elements in a bound- ary-layer wind tunnel

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Journal of Thermal Science 2012年第4期21卷 336-341页

作者： kapil varshney research Department Manager Taitem Engineering PC Ithaca

Boundary-layer wind tunnel provides a unique platform to reproduce urban, suburban and rural atmospheric boundary layer （ABL） by using roughness devices such as vortex generators, floor roughness, barrier wails, and slots in the extended test-section floor in the contraction cone. Each passive device impacts wind properties in a certain way. In this study, influence of various passive devices on wind properties has been investigated. Experi- ments using eighteen different configurations of the passive devices have been carried out to simulate urban, sub-urban, and rural climate conditions in a boundary-layer wind tunnel. The effect of each configuration on the wind characteristics is presented. It was found that higher barrier height and more number of roughness elements on the floor, generated higher turbulence and therefore higher model scale factors were obtained. However, in- creased slot width in the extended test-section floor in the contraction cone of the wind tunnel seemed to have a little effect on wind characteristics.

关键词： Atmospheric boundary layer wind tunnel wind properties roughness elements turbulence.