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Journal of Iron and Steel Research International 2012年第4期19卷 63-68页

作者： S K Ghosh p Mallick p p Chattopadhyay Department of Metallurgy and Materials Engineering Bengal Engineering and Science UniversityShibpurHowrah 711 103India

The effects of cold deformation on the formation of strain induced α’ martensite and mechanical properties of an austenitic stainless steel have been examined.X-ray diffraction analysis has revealed that 30% and 40% cold rolling have resulted in the formation of 24% and 31.5% martensite *** investigation has demonstrated that the formation of martensite is enhanced with increase in the percent deformation at 0 ℃.Investigation of mechanical properties reveals that hardness,yield strength and tensile strength values increase where as percent elongation drops with increasing *** fractographic observation corroborates the tensile *** of sub-surface at the fractured end of the tensile sample manifests that void/microcrack nucleation occurs in the interfacial regions of the martensite phase as well as at the austenite-martensite interface

关键词： austenitic stainless steel cold deformation martensite mechanical property

Structural and physical property Analysis of ZnO-SnO_2—In_2O_3—Ga_2O_3 Quaternary Transparent Conducting Oxide System

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Journal of Materials Science & Technology 2013年第5期29卷 419-422页

作者： p.Jayaram T.p.Jaya Smagul Zh.Karazhanov p.p.pradyumnan Department of physics University of CalicutCalicut University(P.O.)Malappuram DistrictKerala 673 635India Department for Solar Energy Institute for Energy TechnologyInstituttveien 182027 KjellerNorway

The increasing demand in the diverse device applications of transparent conducting oxides （TCOs） requires synthesis of new TCOs of n- or p-type conductivity. This article is about materials engineering of ZnO-SnO2- In2O3-Ga2O3 to synthesize powders of the quaternary compound Zn2-xSn1-xlnxGaxO4-δ in the stoichiometry of x = 0.2, 0.3, and 0.4 by solid state reaction at 1275℃. Lattice parameters were determined by X-ray diffraction （XRD） technique and solubility of In3＋ and Ga3＋ in spinel Zn2SnO4 was found at 1275℃. The solubility limit of In3＋ and Ga3＋ in Zn2SnO4 is found at below x = 0.4. The optical transmittance approximated by the UV-Vis reflectance spectra showed excellent characteristics while optical band gap was consistent across 3.2 eV with slight decrease along increasing x value. Carrier mobility of the species was considerably higher than the older versions of zinc stannate spinel co-substitutions whereas the carrier concentrations were moderate.

关键词： Transparent conducting oxides (TCOs) Structural studies Mobility Optical properties

DENOISING AND HARMONIC DETECTION USING NONORTHOGONAL WAVELET pACKETS IN INDUSTRIAL AppLICATIONS

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Journal of Systems Science & Complexity 2007年第3期20卷 325-343页

作者： p.MERCORELLI Department of Vehicles Production and Process EngineeringUniversity of Applied Sciences WolfsburgRobert-Koch-Platz 8-a.38440 WolfsburgGermany.

New industrial applications call for new methods and new ideas in signal analysis. Wavelet packets are new tools in industrial applications and they have just recently appeared in projects and patents. In training neural networks, for the sake of dimensionality and of ratio of time, compact information is needed. This paper deals with simultaneous noise suppression and signal compression of quasi-harmonic signals. A quasi-harmonic signal is a signal with one dominant harmonic and some more sub harmonics in superposition. Such signals often occur in rail vehicle systems, in which noisy signals are present. Typically, they are signals which come from rail overhead power lines and are generated by intermodulation phenomena and radio interferences. An important task is to monitor and recognize them. This paper proposes an algorithm to differentiate discrete signals from their noisy observations using a library of nonorthonormal bases. The algorithm combines the shrinkage technique and techniques in regression analysis using Shannon Entropy function and Cross Entropy function to select the best discernable bases. Cosine and sine wavelet bases in wavelet packets are used. The algorithm is totally general and can be used in many industrial applications. The effectiveness of the proposed method consists of using as few as possible samples of the measured signal and in the meantime highlighting the difference between the noise and the desired signal. The problem is a difficult one, but well posed. In fact, compression reduces the level of the measured noise and undesired signals but introduces the well known compression noise. The goal is to extract a coherent signal from the measured signal which will be ＂well represented＂ by suitable waveforms and a noisy signal or incoherent signal which cannot be ＂compressed well＂ by the waveforms. Recursive residual iterations with cosine and sine bases allow the extraction of elements of the required signal and the noise. The algorithm

关键词： Data compression denoising rail vehicle control trigonometric bases wavelet packets.

Throughflow and g-jitter effects on binary fluid saturated porous medium

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Applied Mathematics and Mechanics(English Edition) 2015年第10期36卷 1285-1304页

作者： p.KIRAN Department of Applied Mathematics School for Physical Sciences Babasaheb Bhimrao Ambedkar University

A non-autonomous complex Ginzburg-Landau equation （CGLE） for the finite amplitude of convection is derived, and a method is presented here to determine the amplitude of this convection with a weakly nonlinear thermal instability for an oscillatory mode under throughflow and gravity modulation. Only infinitesimal disturbances are considered. The disturbances in velocity, temperature, and solutal fields are treated by a perturbation expansion in powers of the amplitude of the applied gravity field. Throughfiow can stabilize or destabilize the system for stress free and isothermal boundary conditions. The Nusselt and Sherwood numbers are obtained numerically to present the results of heat and mass transfer. It is found that throughfiow and gravity modulation can be used alternately to heat and mass transfer. Further, oscillatory flow, rather than stationary flow, enhances heat and mass transfer.

关键词： weakly nonlinear theory throughflow complex Ginzburg-Landau equation(CGLE) gravity modulation

Motion through spherical droplet with non-homogenous porous layer in spherical container

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Applied Mathematics and Mechanics(English Edition) 2020年第7期41卷 1069-1082页

作者： p.K.YADAV A.TIWARI p.SINGH Department of Mathematics Motilal Nehru National Institute of Technology AllahabadPrayagraj 211004India Department of Mathematics Birla Institute of Technology SciencePilani 333031Rajasthan Department of Mathematics National Institute of Technology PatnaPatna 800005India

The problem of the creeping flow through a spherical droplet with a non-homogenous porous layer in a spherical container has been studied ***’s model for the flow inside the porous annular region and the Stokes equation for the flow inside the spherical cavity and container are used to analyze the *** drag force is exerted on the porous spherical particles enclosing a cavity,and the hydrodynamic permeability of the spherical droplet with a non-homogeneous porous layer is *** is placed on the spatially varying permeability of a porous medium,which is not covered in all the previous works related to spherical *** variation of hydrodynamic permeability and the wall effect with respect to various flow parameters are presented and discussed *** streamlines are presented to discuss the kinematics of the *** previous results for hydrodynamic permeability and drag forces have been verified as special limiting cases.

关键词： non-homogenous porous medium Stokes equation Darcy’s law perme-ability parameter wall effect

On the Optimization of performance of Hg_xCd_(1-x)S Based Electrochemical photosensing Cell

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稀有金属材料与工程 2012年第S1期41卷 43-46页

作者： Lendave S AL p pingale p CL p Deshmukh L p Thin Film and Solar Studies Research Laboratory Department of Physics(Appli.Elect.)Solapur UniversitySolapur-413255M.S.India

Chemical growth process that favours deposition of semiconductor materials from a liquid phase was used to obtain CdS and HgxCd1-xS(0≤x≤0.25)photosensitive thin film electrodes on the stainless steel *** deposition of these series of thin films was carried out under the optimized conditions of temperature(60℃),time(90 min)and pH(10.8±0.2).These films were then employed as photosensitive electrode in an electrochemical photosensing cell consisting of sulphide/polysulphide redox electrolyte and a graphite counter *** cells were illuminated by an input illumination intensity of 13 mW/cm 2 and the cell characteristic parameters namely photocurrent(Iph),photo voltage(Vph),the quantum conversion efficiency(η%)and fill factor(ff %)have been *** Vph and Iph have been found to be boosted as the electrode composition is *** conversion efficiency and fill factor enhanced from 0.52%to 1.30%and 31.8%to 37.8%,respectively for the change of electrode composition from 0 to *** of junction ideality factor(nd)showed recombination mechanism at the electrode-electrolyte *** height measurements gave pool-Frenkel type conduction *** flat band potentials(Vfb)were determined for all the cells and found to be enhanced with x up to 0.08 and then decreased for further increase in *** lighted junction quality factor(nL)is increased from 1.49 to 2.94 as the photoelectrode composition(x)was varied from 0 to *** barrier heights(B)at the electrode/electrolyte interfaces were also *** is found that B is higher for a cell of electrode composition equal to *** spectral studies on these cells showed the cut off wavelength(λc)shifted from 530 nm to 800 *** transient response studies showed presence of surface states at the interface that causes Fermi-level ***,performance of the electrochemical photosensing cell is found to be improved after Hg-corboration in CdS and is optimum at x= 0.0

关键词： electrochemical cell photosensing fill factor interface states photovoltage photocurrent

Respiration and Sorption of Water-Extractable Organic Carbon as Affected by Addition of Ca^(2+),Isolated Clay or Clay-Rich Subsoil to Sand

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pedosphere 2014年第1期24卷 98-106页

作者： p.ROYCHAND p.MARSCHNER Soils School of AgricultureFood and WineThe Waite Research InstituteThe University of Adelaide Department of Agricultural Sciences La Trobe UniversityMelbourne Campus

Clay addition to light-textured soils is used to ameliorate water repellency and to increase nutrient retention. However, clay addition may also increase the potential to bind organic matter and thus C sequestration. Divalent calcium ions （Ca2＋） play an important role in binding of organic matter to clay because they provide the bridge between the clay particles and organic matter which are both negatively charged. In the first experiment, quartz sand was mixed with clay isolated from a Vertosol at rates of 0, 50 and 300 g kg-1, finely ground mature wheat residues （20 g kg-1） and powdered CaSO4 at 0, 5 and 10 g kg-1. Soil respiration was measured over 28 d. Compared to the sand alone, addition of isolated clay at 300 g kg-1 increased cumulative respiration with a stronger increase than that at 50 g kg-1. Addition of CaSO4 increased electrical conductivity, decreased sodium adsorption ratio and reduced cumulative respiration. The latter can be explained by enhanced sorption of organic matter to clay via Ca2＋ bridges. In a second experiment, isolated clay or subsoil of the Vertosol without or with powdered CaSO4 at 10 g kg-1 were used for a batch sorption with water-extractable organic C （WEOC） from wheat straw followed by desorption with water. Addition of 10 g kg-1 CaSO4 increased sorption and decreased desorption of WEOC in both subsoil and isolated clay. In the third experiment, subsoil of the Vertosol was used for a batch sorption in which WEOC was added repeatedly. Repeated addition of WEOC increased the concentration of sorbed C but decreased the sorbed proportion of the added WEOC. This indicates that sorption of WEOC may be underestimated if it is added only once in batch sorption experaments.

关键词： calcium carbon sequestration decomposition desorption Vertosol

Exploring the concept of castability in magnesium die-casting alloys

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Journal of Magnesium and Alloys 2021年第1期9卷 102-111页

作者： J.p.Weiler Meridian Lightweight Technologies Canada

This paper provides a summary of the recent work completed and history of the measure of manufacturability in the magnesium diecasting *** most popular die-casting alloys utilized in this industry are based on the Mg-Al system,including AZ91,AM60 and *** are well-established alloys,and are generally considered to be highly ***,the concept of castability in magnesium die-casting is not a well-defined characteristic or quantitative material *** a result,the author investigates the subject of castability for magnesium die-cast alloys and how it relates to the development of alloys for innovative applications or improved *** paper provides a summary of some key findings in literature on the castability of magnesium die-cast alloys,how castability is defined and evaluated,the impact of different alloying elements on the castability of magnesium alloys,and suggestions for future work.©2020 published by Elsevier *** behalf of Chongqing University.

关键词： casting alloys property.

preparation and characterization of colloidal dispersions of graphene-like structures from different ranks of coals

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燃料化学学报 2017年第8期45卷 897-907页

作者： D.p.Savitskii Institute of Biochemical Technology and Nanotechnology RUDN University

This paper focuses on preparation of colloidal solution of graphene-like structures from different ranks of coals: brown coal,bituminous coal,low-volatile bituminous coal,anthracite. It was found that brown coal thermo-oxidative destruction leads to formation of small d = 32 nm( V = 17%) and large d = 122 nm( V = 11%) fractions of nanoparticles. The thermo-oxidative destruction of bituminous coal leads to formation of nanoparticles d = 50 nm( V = 5.2%) and d = 164 nm( V = 16%). Thermooxidative destruction of low-volatile bituminous coal and anthracite leads to formation of nanoparticles,predominantly,d = 122-190 nm. Carbon nanostructures obtained from coal are negatively charged at pH= 2-12. Colloidal solution of carbon nanostructures at dispersed phase concentration 0. 01 mg/mL is stable for 1 month. Electron diffraction patterns and X-ray analysis of carbon nanostructures showed that nanostructure from brown coal is amorphous and nanostructure from anthracite is crystalline. Results of coal macromolecules modeling and graphene-like structures obtained from them are presented.

关键词：象 graphene 一样结构煤胶体的分散粒子尺寸分发 electrokinetic 潜力

Vasectomy reversal： a clinical update

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Asian Journal of Andrology 2016年第3期18卷 365-371,I0007页

作者： Abhishek p patel Ryan p Smith Department of Urology University of Virginia Charlottesville VA 22908-0422 USA.

Vasectomy is a safe and effective method of contraception used by 42-60 million men worldwide. Approximately 3%-6% of men opt for a vasectomy reversal due to the death of a child or divorce and remarriage, change in financial situation, desire for more children within the same marriage, or to alleviate the dreaded postvasectomy pain syndrome. Unlike vasectomy, vasectomy reversal is a much more technically challenging procedure that is performed only by a minority of urologists and places a larger financial strain on the patient since it is usually not covered by insurance. Interest in this procedure has increased since the operating microscope became available in the 1970s, which consequently led to improved patency and pregnancy rates following the procedure. In this clinical update, we discuss patient evaluation, variables that may influence reversal success rates, factors to consider in choosing to perform vasovasostomy versus vasoepididymostomy, and the usefulness of vasectomy reversal to alleviate postvasectomy pain syndrome. We also review the use of robotics for vasectomy reversal and other novel techniques and instrumentation that have emerged in recent years to aid in the success of this surgery.

关键词： epididymovasostomy microsurgery postvasectomy orchialgia postvasectomy pain syndrome vas deferens vasectomy vasectomy reversal vasoepididymostomy vasovasostomy