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substrate Evolution to Microstructural and Optoelectrical Properties of Evaporated Cds Thin Films Correlated with Elemental Composition

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Acta Metallurgica sinica(English Letters) 2021年第9期34卷 1307-1316页

作者： Anuradha Purohit Himanshu s.L.Patel s.Chander M.s.Dhaka Department of Physics Mohanlal Sukhadia UniversityUdaipur 313001India Department of Chemical sciences Indian Institute of Science Education and Research.Mohali 140306India Centre for Advanced study in Physics Department of PhysicsPanjab UniversityChandigarh 160014India

A typical high-e fficiency solar cell device needs the best lattice matching between different constituent layers to mitigate the open-circuit voltage loss. In the present work, the physical properties of Cds thin films are investigated where films with 100 nm thickness were fabricated on the different types of substrates viz. soda–lime glass, indium-doped tin oxide(ITO)-and fl uorine-doped tin oxide(FTO)-coated glass substrates, and silicon wafer using electron beam evaporation. The X-ray diffraction patterns confirmed that deposited thin films showed cubic phase and had(111) as predominant orientation where the structural parameters were observed to be varied with nature of substrates. The ohmic behaviour of the Cds films was disclosed by current–voltage characteristics, whereas the scanning electron microscopy micrograph revealed the uniform deposition of the Cds films with the presence of round-shaped grains. The elemental analysis confirmed the Cds films deposition where the Cd/s weight percentage ratio was changed with nature of substrates. The direct energy band gap was observed in the 1.63–2.50 eV range for the films grown on different substrates. The investigated properties of thin Cds layers demonstrated that the selection of substrate(in terms of nature) during device fabrication plays a crucial role.

关键词： Cds thin films substrate evolution E-beam evaporation Microstructural properties Optoelectrical properties

Intergrain contact density indices for granular mixes——Ⅱ: Liquefaction resistance

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Earthquake Engineering and Engineering Vibration 2007年第2期6卷 135-146页

作者： s. Thevanayagam Dept. of Civil Struct. & Env. Eng. State Univ. of New York Buffalo NY 14260 USA

Whether the presence of non-plastic silt in a granular mix soil impact its liquefaction potential and how to evaluate liquefaction resistance of sand containing different amounts of silt contents are both controversial issues. This paper presents the results of an experimental evaluation to address these issues. Two parameters, namely, equivalent intergranular void ratio （ec）eq and equivalent interfine void ratio （ef）eq, proposed in a companion paper （Thevanayagam, 2007） as indices of active grain contacts in a granular mix, are used to characterize liquefaction resistance of sands and silty sands. Results indicate that, at the same global void ratio （e）, liquefaction resistance of silty sand decreases with an increase in fines content （Cv） up to a threshold value （Crth）. This is due to a reduction in intergrain contact density between the coarse grains. Beyond Crth, with further addition of fines, the interfine contacts become significant while the inter-coarse grain contacts diminish and coarse grains become dispersed. At the same e, the liquefaction resistance increases and the soil becomes stronger with a fttrther increase in silt content. Beyond a limiting fines content （CrL）, the liquefaction resistance is controlled by interfine contacts only. When Cr〈Crth, at the same （e）eq, the liquefaction resistance of silty sand is comparable to that of the host clean sand at a void ratio equal to （ec）eq. When CF〉CFth, at the same （ef）eq, the cyclic strength of a sandy silt is comparable to the host silt at a void ratio equal to （ef）eq.

关键词： sand silt fines silty sand liquefaction cyclic strength

Rock joint coefficients and their computerized classification

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International Journal of Mining science and Technology 2019年第5期29卷 701-709页

作者： Tomás Ficker Faculty of Civil Engineering Brno University of Technology60200 BrnoCzech Republic

A computerized method for determining rock joint coefficients is *** relative similarity indicators are introduced to classify surface morphology of rock *** classification enables to compare investigated and database rock *** a comparison aims at finding the couple of surfaces that are distinguished by the highest dynamical *** first absolute indicator results from the Fourier matrix and evaluates wavy shapes of *** second absolute indicator quantifies the heights of surface reliefs and is defined as the root mean square height of the surface *** reliability of these indicators is tested within the surface analysis of a series of limestone *** the computerized assessment,25 people have performed visual assessment of these limestone *** results of visual assessments have been statistically processed and compared to the results received from the computerized *** newly introduced absolute indicators have proved to be prospective numerical tools for evaluating joint rock coefficients.

关键词： Rock joints shear strength Joint rock coefficients Numerical indicators Computerized assessment

Fibre optic distributed scattering sensing system:perspectives and challenges for high performance applications

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仪器仪表学报 2007年第8期28卷 1345-1352页

作者： Marc Niklès Omnisens sA Riond-Bosson 3CH-1110 MorgesSwitzerland

As fiber optic distributed scattering sensing systems are providing innovative solutions for the monitoring of large structures,the comparison of different techniques and solutions is difficult because of the lack of standardized specifications and the difficulty associated to the characterization of such *** article presents a tentative definition of performance specifications and qualification procedures applicable to fiber optic distributed sensing systems aiming at providing clear guidelines for their design,specifications,qualification,application and selection.

关键词：纤维光学传感器分布式散射传感系统发展前景应用布里渊散射空间分辨率温度

Intergrain contact density indices for granular mixes——Ⅰ: Framework

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Earthquake Engineering and Engineering Vibration 2007年第2期6卷 123-134页

作者： s. Thevanayagam Dept. of Civil Struct. and Envir. Eng. State University of New York Buffalo NY 14260 USA

Mechanical behavior such as stress-strain response, shear strength, resistance to liquefaction, modulus, and shear wave velocity of granular mixes containing coarse and fine grains is dependent on intergrain contact density of the soil. The global void ratio e is a poor index of contact density for such soils. The contact density depends on void ratio, fine grain content （Cv）, size disparity between particles, and gradation among other factors. A simple analysis of a two-sized particle system with large size disparity is used to develop an understanding of the effects of Cv, e, and gradation of coarse and fine grained soils in the soil mix on intergrain contact density. An equivalent intergranular void ratio （ec）oq is introduced as a useful intergrain contact density for soils at fines content of less than a threshold value Crth. Beyond this value, an equivalent interfine void ratio （ef）eq is introduced as a primary intergrain contact density index. At higher values of Cv beyond a limiting value of fine grains content CVL, an interfine void ratio ef is introduced as the primary contact density index. Relevant equivalent relative density indices （Drc）eq and （Drf）eq are also presented. Experimental data show that these new indices correlate well with steady state strength, liquefaction resistance, and shear wave velocities of sands, silty sands, sandy silts, and gravelly sand mixes.

关键词： sand silt silty sand sandy silt cyclic strength shear wave velocity intergrain contact density

Laser-induced thermal lens study of the role of morphology and hydroxyl group in the evolution of thermal diffusivity of copper oxide

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Chinese Physics B 2021年第6期30卷 588-593页

作者： Riya sebastian M s swapna Vimal Raj s sankararaman Department of Optoelectronics University of KeralaTrivandrum 695581KeralaIndia

The paper explores the evolution of thermal behavior of the material by studying the variations in thermal diffusivity using the single beam thermal lens(TL) technique. For this purpose, the decomposition of Cu(OH)_(2) into CuO is studied in a time range up to 120 h, by subjecting the sample to morphological, structural, and spectroscopic characterizations. The time evolution of thermal diffusivity can be divided into three regions for demonstrating the dynamics of the reaction. When the reaction is complete, the thermal diffusivity is also found to be saturated. In addition to the morphological modifications,from rods to flakes, the variations in the amount of hydroxyl group are attributed to be responsible for the enhancement of base fluid's thermal diffusivity by 165%. Thus the study unveils the role of hydroxyl groups in the thermal behavior of CuO.

关键词： thermal diffusivity CuO thermal lens morphology hydroxyl group

Effects of wave propagation anisotropy on the wave focusing by negative refractive sonic crystal flat lenses

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Chinese Physics B 2012年第12期21卷 355-365页

作者： s.Alagoz Department of Physics Inonu University

In this study, wave propagation anisotropy in a triangular lattice crystal structure and its associated waveform shaping in a crystal structure are investigated theoretically. A directional variation in wave velocity inside a crystal structure is shown to cause bending wave envelopes. The authors report that a triangular lattice sonic crystal possesses six numbers of a high symmetry direction, which leads to a wave convergence caused by wave velocity anisotropy inside the crystal. However, two of them are utilized mostly in wave focusing by an acoustic fiat lens. Based on wave velocity anisotropy, the pseudo ideal imaging effect obtained in the second band of the flat lens is discussed.

关键词： sonic crystal wave focusing fiat lens ideal imaging

New analytical exact solutions of time fractional KdV KZK equation by Kudryashov methods

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Chinese Physics B 2016年第4期25卷 30-36页

作者： s saha Ray National Institute of Technology Department of Mathematics

In this paper, new exact solutions of the time fractional KdV-Khokhlov-Zabolotskaya-Kuznetsov （KdV-KZK） equa- tion are obtained by the classical Kudryashov method and modified Kudryashov method respectively. For this purpose, the modified Riemann-Liouville derivative is used to convert the nonlinear time fractional KdV-KZK equation into the non- linear ordinary differential equation. In the present analysis, the classical Kudryashov method and modified Kudryashov method are both used successively to compute the analytical solutions of the time fractional KdV-KZK equation. As a result, new exact solutions involving the symmetrical Fibonacci function, hyperbolic function and exponential function are obtained for the first time. The methods under consideration are reliable and efficient, and can be used as an alternative to establish new exact solutions of different types of fractional differential equations arising from mathematical physics. The obtained results are exhibited graphically in order to demonstrate the efficiencies and applicabilities of these proposed methods of solving the nonlinear time fractional KdV-KZK equation.

关键词： KdV-Khokhlov-Zabolotskaya-Kuznetsov equation Kudryashov method modified Kudryashovmethod fractional complex transform modified Riemann-Liouville derivative

A Review on Diverse silver Nanostructures

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Journal of Materials science & Technology 2010年第6期26卷 487-522页

作者： s.Vongehr National Laboratory of solid state Microstructures Department of Materials Science and EngineeringNanjing University

This article reviews recent advances in the utilization of various water based synthesis routes towards the shape-controlled synthesis of silver nanoparticles and microstructures in a diverse range of shapes and sizes from several nanometers to micrometers. A variety of very simple one-pot methods, at times employing com- mercial microwave ovens, inexpensive low power ultrasound cleaners, or two-electrode electro-chemistry, can be surprisingly effective in the controlled synthesis of a wide range of nanostructured products, if only parameters are carefully chosen. Many approaches which are adopted include synthesis of Ag nanostructures with various shapes in solution, doping of Ag nanoparticles on unmodified silica and on/inside carbon spheres, kinetically controlled growth of Ag micro-particles with novel nanostructures on flat substrates, and galvanic replace- ment towards bimetallic Ag-Au dendrites and carbon composites. Characterizations of shape, composition and microstructure are carried out via scanning and transmission electron microscopy, various spectroscopy methods, N2 absorption measurements and suchlike. The involved growth mechanisms are investigated in order to discover new means towards better control. size, location and shape control, including micro- and nanostructure features, allows tuning the products properties towards desired applications. We focus on the optical properties and catalytic activities, but also the stability of compounds can be an issue of interest.

关键词： silver Nanostructures synthesis Thermal stability surface plasmon resonance Catalysis