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CdS nanostructures have grown on p-type silicon (Si) (100) substrates using sol–gel method. The crystalline quality, surface morphology, optical and electrical properties of the deposited CdS nanostructures have been characterized and analyzed using atomic force microscopy, scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, differential thermal analysis, UV–vis spectroscopy and electrical characterization, respectively. The effect of annealing temperature in the range 200–600 °C on the structural, morphological, optical and electrical properties has been elaborated. The XRD analysis shows that the crystalline quality can be improved by increasing the temperature to 400 °C, but further increase to 600 °C leads to degradation of crystalline quality. The bulk modulus is calculated and showed good agreement with experimental and theoretical results. The optical properties of absorption, reflection, energy band gap and extinction coefficient are obtained by UV–vis spectroscopy. The calculated refractive index and optical dielectric constant have shown good agreement with other results. The electrical and thermal properties are studied for antireflection coating applications. 相似文献
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Fuzzy hypersemigroups 总被引:1,自引:0,他引:1
M. K. Sen Reza Ameri G. Chowdhury 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2008,12(9):891-900
We introduce the notions of fuzzy hypersemigroup, fuzzy hypergroup, fuzzy hyperideal, homomorphism, hyper congruence, fuzzy
homomorphism, fuzzy hypercongruence. The purpose of this note is the study of some characterization of fuzzy hypersemigroup,
fuzzy hyperideal of a fuzzy hypersemigroup and homomorphism and hypercongruence on a hypersemigroup. 相似文献
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This investigation presents an optimization of laminated cylindrical panels based on fundamental natural frequency. Also, trends of change in optimum stacking sequence while the proportions of structures vary, are studied which can be insightful for design purposes. A displacement based finite element model is used, in order to extract fundamental natural frequencies of T300/5208 Carbon/Epoxy cylindrical panels. To obtain optimum designs, the Globalized Bounded Nelder–Mead (GBNM) algorithm is employed. Predictions are compared with the results of Genetic Algorithm (GA) method and show faster and more accurate convergence to the global optimum, while variables are continuous in GBNM and discrete in GA. Moreover, verification of novel convergence criteria to ameliorate local searcher in GBNM is examined. 相似文献
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We introduce and study the notion of fuzzy multialgebras on the basis of a new definition of a fuzzy hyperoperation. We introduce the notion of fuzzy regular (resp., fuzzy strongly regular) relations of hyperalgebras and obtain their basic properties. Finally, we prove that with every fuzzy hyperalgebra we can associate a unique hyperalgebra via a regular (resp., strongly regular) relation. 相似文献
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Jason J. Chang Ansley Stanfill Tayebeh Pourmotabbed 《International journal of molecular sciences》2016,17(8)
Stroke remains the fifth leading cause of mortality in the United States with an annual rate of over 128,000 deaths per year. Differences in incidence, pathogenesis, and clinical outcome have long been noted when comparing ischemic stroke among different ethnicities. The observation that racial disparities exist in clinical outcomes after stroke has resulted in genetic studies focusing on specific polymorphisms. Some studies have focused on matrix metalloproteinases (MMPs). MMPs are a ubiquitous group of proteins with extensive roles that include extracellular matrix remodeling and blood-brain barrier disruption. MMPs play an important role in ischemic stroke pathophysiology and clinical outcome. This review will evaluate the evidence for associations between polymorphisms in MMP-1, 2, 3, 9, and 12 with ischemic stroke incidence, pathophysiology, and clinical outcome. The role of polymorphisms in MMP genes may influence the presentation of ischemic stroke and be influenced by racial and ethnic background. However, contradictory evidence for the role of MMP polymorphisms does exist in the literature, and further studies will be necessary to consolidate our understanding of these multi-faceted proteins. 相似文献
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In the present work, performance of new configuration of Micro-gas turbine cogeneration and tri-generation systems, with a steam ejector refrigeration system and Heat recovery Steam Generator (HRSG) are studied. A micro-gas turbine cycle produces 200 KW power and exhaust gases of this micro-gas turbine are recovered in an HRSG. The main part of saturated steam in HRSG is used through a steam ejector refrigeration system to produce cooling in summer. In winter, this part of saturated steam is used to produce heating. In the first part of this paper, performance evaluation of this system with respect to Energy Utilization Factor (EUF), Fuel Energy Saving Ratio (FESR), thermal efficiency, pinch point temperature difference, net power to evaporator cooling load and power to heat ratio is carried out. It has been shown that by using the present cogeneration system, one can save fuel consumption from about 23% in summer up to 33% in winter in comparison with separate generation of heating, cooling and electricity. 相似文献
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Analysis of multi-layered filament-wound composite pipes under combined internal pressure and thermomechanical loading with thermal variations 总被引:1,自引:0,他引:1
The composite pipes manufactured by filament winding technology have anisotropic behavior owing to different reinforced ply angles. Composite pipes can be exposed to the thermomechanical loading due to hot fluid that flows into them. In this paper, based on the three-dimensional anisotropic elasticity, an exact elastic solution for thermal stresses and deformations of the pipes under internal pressure and a temperature gradient has been studied. Giving heat convection conditions the variation of temperature field within the pipe is obtained by solving the conduction equation at the wall. The influence of temperature field in the governing equations of thermoelasticity has been considered via a constitutive law. The shear extension coupling is also considered because of lay-up angles. Stress, strain and deformation distributions for different angle-ply pipe designs are investigated using the present theory. 相似文献
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Fei Guo Tayebeh Ameri Karen Forberich Christoph J Brabec 《Polymer International》2013,62(10):1408-1412
Bulk heterojunction based polymer:fullerene solar cells have attracted intensive research interest both in academic and industrial communities in the last two decades, mainly related to their potential low‐cost production process. A power conversion efficiency of over 10% has been reported recently, making the commercialization of this clean and cheap solar energy convertor a realistic prospect for the near future. The intrinsic features of semitransparency and color tunability of the thin polymeric photoactive films are the greatest asset for polymer solar cells. Recently, aesthetic semitransparent polymer solar cells (ST‐PSCs) that can be integrated into transparent windows, roofs, glass and other semitransparent architectural elements have received much attention. In this perspective paper, we present the progress in achieving high performance ST‐PSCs, discuss the requirements for transparent electrodes, focusing on alternatives to tin‐doped indium oxide, and address the challenges ahead to make ST‐PSC viable for real applications. © 2013 Society of Chemical Industry 相似文献
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Hashemizadeh A. Ameri M. J. Aminshahidi B. Gholizadeh M. 《Protection of Metals and Physical Chemistry of Surfaces》2018,54(5):884-892
Protection of Metals and Physical Chemistry of Surfaces - The effect of magnetization of acid before usage (pre-magnetization technique) on the corrosion inhibition of carbon steel (CS) in 7.5, 10... 相似文献