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Chinese Physics Letters 2006年第2期23卷 370-373页

作者： Raid A. Ismail k.dhim A. Hubeatir Abdullah k. Abass Department of Applied Physics Ministry of Technology Baghdad Iraq Department of Optoelectronics University of Technology Baghdad Iraq

Amorphous/crystalline n-n-isotype Si heterojunetions are made by a pulsed Q-switched second harmonic generation nd：YAG laser. The process includes melting and subsequently fast resolidification of a thin front layer of monocrystalline Si by laser pulses to create an amorphous layer （phase transition）. Different laser energy densities are used to form the amorphous layer on a monocrystalline Si substrate, the results of the electrical characteristics of the heterojunctions are dependent strongly on the laser energy density. Optoelectronic properties such as current-voltage, capacitance voltage, and spectral sensitivity are measured in a-Si/c-Si hereto junctions （in the absence of anti-reflecting coating and frontal grid contact） prepared by different laser energy densities. The built-in-potential values extracted from current-voltage measurements are close to the published results of （n-p） amorphous/crystalline hereto junction made by glow discharge and plasma enhanced chemical vapour deposition. Furthermore, examination of the formation of amorphous pattern on Si surface is carried out with the help of optical microscopy. Best photovoltaic performance is recognized to be at ,5.6 J/cm^2. The photodetector shows a wide spectral response, and the peak.response is at 780nm. On the other hand, this peak.is independent of laser energy.

关键词： CRYSTALLInE SILICOn SOLAR-CELLS

MHD non-newtonian micropolar fluid flow and heat transfer in channel with stretching walls

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Applied Mathematics and Mechanics(English Edition) 2013年第10期34卷 1263-1276页

作者： M. ASHRAF n. JAMEEL k. ALI Centre for Advanced Studies in Pure and Applied Mathematics Bahauddin Zakariya UniversityMultan 60800 Pakistan Centre for Advanced Studies in Pure and Applied Mathematics Bahauddin Zakariya UniversityMultan 60800 Pakista

A study is presented for magnetohydrodynamics （MHD） flow and heat transfer characteristics of a viscous incompressible electrically conducting micropolar fluid in a channel with stretching walls. The micropolar model introduced by Eringen is used to describe the work.ng fluid. The transformed self similar ordinary differential equations together with the associated boundary conditions are solved numerically by an algorithm based on quasi-linearization and multilevel discretization. The effects of some physical parameters on the flow and heat transfer are discussed and presented through tables and graphs. The present investigations may be beneficial in the flow and thermal control of polymeric processing.

关键词： magnetohydrodynamics (MHD) heat transfer stretching wall couple stress quasi-linearization

Quality of spring water used for irrigation in the Almora District of Uttarak.and, India

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Chinese Journal Of Geochemistry 2013年第2期32卷 130-136页

作者： Bhandari n. S. Hemant k. Joshi Department of Chemistry Kumaun University S. S. J. Campus Almora-263601 Uttarakhand India

This paper aims to propose a quality profile of springs of the study area for irrigation. In the present study, fifty-four springs in Almora have been identified from rural as well as urban localities for calculation of irriga- tional water quality parameters during pre-monsoon, monsoon and post-monsoon, 2008. Spring water samples are collected and analyzed for pH, electrical conductivity (EC), total dissolved solids (TDS), na+ , k. , Ca2+ , Mg2+ , HCO3- , Cl- , and SO42- . Different irrigation quality parameters viz. salinity, sodium adsorption ratio (SAR), soluble sodium percentage (SSP), residual sodium carbonate (RSC), magnesium hazards (MH) and permeability index (PI) are calculated for the evaluation of spring water quality for irrigation purposes. All springs are found excellent to good based on irrigation quality parameters. Based on Wilcox diagram, about 98% of the water resources are grouped as C1S1 (low-low) and C2S1 (medium-low) classes, so springs are suitable for normal irrigation.

关键词：质量档案灌溉泉水印度钠吸附比水质参数总溶解固体研究区域

Effects of Impurity on Microstructure and Hardness in Pure Al Subjected to Dynamic Plastic Deformation at Cryogenic Temperature

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Journal of Materials Science & Technology 2011年第7期27卷 628-632页

作者： F. Huang n.R. Tao k. Lu Shenyang national Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Microstructure and hardness were investigated in pure Al samples with different purities （5n： 99.999%, 4n： 99.993%, and 2n： 99.7% in weight） subjected to dynamic plastic deformation at cryogenic temperatures. The saturated sizes of refined grains/subgrains in these samples induced by plastic deformation are about 240 nm without an obvious impurity effect, but the dislocation density in 2n Al is evidently higher than that in other samples. Boundary misorientations for 5n and 4n Al are below 10° with average values of 2–3°, while the average misorientation for 2n Al is obviously larger, being about 14°. Microhardness of LnT-DPD 2n Al is higher than that of 5n and 4n Al, owing to the enhanced dislocation density as their grain/subgrain sizes are almost identical.

关键词： Aluminum Impurity nanostructure Grain refinement

Effect of Temperature on Grain Size in AA6063 Aluminum Alloy Subjected to Repetitive Corrugation and Straightening

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Acta Metallurgica Sinica(English Letters) 2019年第7期32卷 835-844页

作者： n. Thangapandian S. Balasivanandha Prabu k. A. Padmanabhan Department of Mechanical Engineering St. Joseph's Institute of Technology Chennai 600119 India Department of Mechanical Engineering College of Engineering Guindy Anna University. Chennai 600025 India

The influence of processing temperature on grain size reduction in AA 6063 aluminum alloy subjected to repetitive corrugation and straightening (RCS) is investigated in this work. The aluminum alloy was processed by RCS at different temperatures (room temperature, 100 ℃, 200 ℃ and 300 ℃) till the maximum number of passes possible before failure and the mechanical properties such as tensile strength and hardness were measured. The grain size and their misorientation of grains of the processed samples were analyzed using the electron back.cattered diffraction. The results indicated that the transformation of low-angle grain boundaries to high-angle grain boundaries and dislocation tangles were highly dependent on the strain imparted, which could be controlled by selecting the proper processing temperature. As a result, the mechanical properties are affected. In particular, the room temperature tensile strength and hardness values of the processed material decrease with increasing processing temperature.

关键词： Repetitive corrugation and straightening Strain Grain size reduction/refinement EBSD Strength Hardness

Elastic and Optoelectronic Properties of k.dF3:ab initio Calculations through LDA/GGA/TB-mBJ within FP-LAPW Method

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Chinese Physics Letters 2015年第1期32卷 108-112页

作者： k. Ephraim Babu n. Murali k. Vijaya Babu B. k.shore Babu V. Veeraiah Modelling and Simulation in Materials Science Laboratory Department of Physics Andhra University Visakhapatnam 530003 Andhra Pradesh India Department of Engineering Chemistry A UCE(A) Andhra University Visakhapatnam 530003 Andhra Pradesh India

Ab initio calculations are performed on the electronic, structural, elastic and optical properties of the cubic per- ovsk.te k.dF3. Tile k.hn Sham equations are solved by applying the full potential linearized augmented plane wave （FP-LAPW） method. The exchange correlation effects are included through the local density approximation （LDA ）, generalized gradient approximation （GGA） and modified Beck.-Johnson （mBJ） exchange potential The calculated lattice constant is in good agreement with the experimental result. The elastic properties such as elastic constants, anisotropy factor, shear modulus, Young＇s modulus and Poisson＇s ratio are calculated. k.dF3 is ductile and elastically anisotropic. The calculations of the electronic band structure, density of states （DOS） and charge density show that this compound has an indirect energy band gap （M-F） with a mixed ionic and covalent bonding. The contribution of the different bands is analyzed from the total and partial density of states curves. Optical response of the dielectric functions, optical reflectivity, absorption coefficient, real part of optical conductivity, refractive index, extinction coefficient and electron energy loss, are presented for the energy range of O-40eV. The compound k.dF3 can be used for high-frequency optical and optoelectronic devices.

关键词： GGA Cd Elastic and Optoelectronic Properties of k.dF3:ab initio Calculations through LDA/GGA/TB-mBJ within FP-LAPW Method LDA FP

Olfactory receptors in neural regeneration in the central nervous system

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neural Regeneration Research 2025年第9期20卷 2480-2494页

作者： Rafael Franco Claudia Garrigós Toni Capó Joan Serrano-Marín Rafael Rivas-Santisteban Jaume Lillo Molecular neurobiology Laboratory Department of Biochemistry and Molecular BiomedicineFacultat de BiologiaUniversitat de BarcelonaBarcelonaSpain Ciberned network.Center for Biomedical Research in neurodegenerative Diseases Spanish National Health Institute Carlos ⅢMadridSpain School of Chemistry Universitat de BarcelonaBarcelonaSpain Department of Biochemistry and Physiology School of Pharmacy and Food SciencesUniversitat de BarcelonaBarcelonaSpain Laboratory of Computational Medicine Biostatistics UnitFaculty of MedicineAutonomous University of BarcelonaCampus BellaterraBarcelonaSpain

Olfactory receptors are crucial for detecting odors and play a vital role in our sense of smell,influencing behaviors from food choices to emotional *** receptors also contribute to our perception of flavor and have potential applications in medical diagnostics and environmental *** ability of the olfactory system to regenerate its sensory neurons provides a unique model to study neural regeneration,a phenomenon largely absent in the central nervous *** gained from how olfactory neurons continuously replace themselves and reestablish functional connections can provide strategies to promote similar regenerative processes in the central nervous system,where damage often results in permanent *** the molecular and cellular mechanisms underpinning olfactory neuron regeneration could pave the way for developing therapeutic approaches to treat spinal co rd injuries and neurodegenerative diseases lik. Alzheimer's *** ctory receptors are found in almost any cell of eve ry orga n/tissue of the mammalian *** ectopic expression provides insights into the chemical structures that can activate olfactory *** addition to odors,olfactory receptors in ectopic expression may respond to endogenous compounds and molecules produced by mucosal colonizing *** analysis of the function of olfactory receptors in ectopic expression provides valuable information on the signaling pathway engaged upon receptor activation and the receptor's role in proliferation and cell differentiation *** review explo res the ectopic expression of olfa ctory receptors and the role they may play in neural regeneration within the central nervous system,with particular attention to compounds that can activate these receptors to initiate regenerative *** suggests that olfactory receptors could serve as potential therapeutic targets for enhancing neural repair and recovery following central nervous syste

关键词： adenosine receptors adrenergic receptors ectopic expression G proteincoupled receptors glia neurons

Effect of reinforcement content on the adhesive wear behavior of Cu10Sn5ni/Si3n4 composites produced by stir casting

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International Journal of Minerals,Metallurgy and Materials 2017年第9期24卷 1052-1060页

作者： k.Sanesh S.Shiam Sunder n.Radhik. Department of Mechanical Engineering Amrita School of EngineeringCoimbatore 64112Amrita Vishwa VidyapeethamAmrita UniversityIndia

The main objective of this paper was to fabricate CuSnni alloy and its composites reinforced with various contents of Sinparticles(5wt%, 10wt%, and 15wt%) and to investigate their dry sliding wear behavior using a pin-on-disk.tribometer. Microstructural examinations of the specimens revealed a uniform dispersion of Sinparticles in the copper matrix. Wear experiments were performed for all combinations of parameters, such as load(10, 20, and 30 n), sliding distance(500, 1000, and 1500 m), and sliding velocity(1, 2, and 3 m/s), for the alloy and the composites. The results revealed that wear rate increased with increasing load and increasing sliding distance, whereas the wear rate decreased and then increased with increasing sliding velocity. The primary wear mechanism encountered at low loads was mild adhesive wear, whereas that at high loads was severe delamination wear. An oxide layer was formed at low velocities, whereas a combination of shear and plastic deformation occurred at high velocities. The mechanism at short sliding distances was ploughing action of Sinparticles, which act as protrusions; by contrast, at long sliding distances, direct metal–metal contact occurred. Among the investigated samples, the Cu/10wt% Sincomposite exhibited the best wear resistance at a load of 10 n, a velocity of 2 m/s, and a sliding distance of 500 m.

关键词： copper matrix composites stir casting adhesive wear wear mechanisms

Fabrication of cost effective iron ore slime ceramic membrane for the recovery of organic solvent used in cok. production

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International Journal of Coal Science & Technology 2016年第2期3卷 226-234页

作者： V. Singh n. k. Meena A. k. Golder C. Das Department of Chemical Engineering Indian Institute ofTechnology Guwahati Guwahati Assam 781039 India

Improvement of cok.ng properties of sub-bituminous coal （A） and bituminous coal （B） was done using blended organic solvents, namely, n-methyl-2-pyrrolidinone （nMP） and ethylenediamine （EDA）. Various solvent blends were employed for the coal extraction under the total reflux condition. A low-cost ceramic membrane was fabricated using industrial waste iron ore slime of M/s TATA steel R＆D, Jamshedpur （India） to separate out the dissolved cok.ng fraction from the solvent-coal mixture. Membrane separations were carried out in a batch cell, and around 75 % recovered nMP was reused. The fractionated coal properties were determined using proximate and ultimate analyses. In the case of bituminous coal, the ash and sulfur contents were decreased by 99.3 % and 79.2 %, respectively, whereas, the carbon content was increased by 23.9 % in the separated coal fraction. Three different cleaning agents, namely deionized water, sodium dodecyl sulphate and nMP were used to regain the original membrane permeability for the reusing.

关键词： Iron ore slime Solvent recovery Proximate analysis Ultimate analysis Membrane cleaning

Carbon stock.estimation for tree species of Sem Muk.em sacred forest in Garhwal Himalaya, India

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Journal of Forestry Research 2013年第3期24卷 457-460页

作者： nazir A. Pala A. k. negi Yogesh Gok.ale Showk.t Aziem k. k. Vik.ant n. P. Todaria Department of Forestry Dolphin (PG) Institute of Biomedical and Natural SciencesManduwala Dehradun -248007 Uttarakhand India Department of Forestry and natural Resources P.O. Box-59 Chauras Campus HNB Garhwal University Srinagar GarhwalUttarkhand-246174 India The Energy and Resources Institute (TERI) New Delhi 110003 India Plant physiology division Botany discipline FRI Dehradun248006 India

Carbon stock.estimation was conducted in tree species of Sem Muk.em sacred forest in district Tehri of Garhwal Himalaya, Uttara- k.and, India. This forest is dedicated to nagraj Devta and is dominated by tree species, including Quercus floribunda, Quercus semecarpifolia and Rhododendron arboreum. The highest values of below ground bio- mass density, total biomass density and total carbon density were （34.81±1.68） Mg·ha^-1, （168.26±9.04） Mg·ha^-1 and （84.13±4.18） Mg·ha^-1 for Pinus wallichiana. Overall values of total biomass density and total carbon density calculated were 1549.704 Mg·ha^-1 and 774.77 Mg·ha^-1 respectively. Total value of growing stock.volume density for all species was 732.56 m3·ha^-1 and ranged from （144.97±11.98） m3·ha^-1 for Pinus wallichiana to （7.78±1.78） m3·ha^-1for Benthamidia capitata.

关键词： carbon management sacred forest biomass density