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481.
482.
Shashwati Sen P.S. Sarkar G.D. Patra S.G. Singh M. Ghosh S. Pitale A.N. Patil Manoj K. Pal 《Ceramics International》2021,47(2):2187-2193
In this paper we report a novel way of processing CsI powder into poly-crystalline transparent plate by vacuum hot pressing technique. The fabricated CsI plate is investigated for its microstructure and phase purity. Further we have measured the luminescence and scintillation characteristics of this plate. These measurements establish that the polycrystalline plate can have application in radiation detection. Further the efficacy of the transparent CsI plate is shown for industrial X-ray radiography applications. Our results show that this kind of CsI plate can be economically fabricated and can replace the use of CsI single crystals and thin films in specific applications like radiation detection and industrial radiography. 相似文献
483.
Abhyarthana Pattanaik Satyananda Patra Venugopal Rayasam 《Transactions of the Indian Institute of Metals》2020,73(1):47-63
Detailed characterization study is the pioneer step for any mineral beneficiation scheme. A series of mineralogical and peterographic studies coupled with (Brunauer–Emmett–Teller) surface area, (atomic force microscopy), (laser diffraction particle size analyser), FTIR (Fourier transform infrared spectroscopy), contact angle measurement, zeta potential were carried out, and the findings about the mineralogical and physico-chemical nature of the sample have been described. This paper provides a guide on the proper selection of beneficiation route for iron ore with complex mineral assemblage (Hematite–Goethite–Laterite–Quartz–Kaolinite–Gibbsite). The beneficiation method, especially froth flotation process, potential after a thorough characterization is suggested analysed and the successful upgradation by froth flotation route is envisaged. Flotation results indicated that it is possible to achieve high grade iron concentrate along with lower silica, and alumina content providing a specific reagent regime/system for specific mineral assemblages. 相似文献
484.
Akhtarkavan Ehsan Majidi Babak Salleh M. F. M. Patra Jagdish C. 《Multimedia Tools and Applications》2020,79(19-20):13427-13447
Multimedia Tools and Applications - Data hiding in digital multimedia has been extensively used for sensitive data transmission and data authentication. An important property of data hiding which... 相似文献
485.
In this research paper, an optimized 2 × 2 MIMO UWB antenna (antenna‐E) with half circled radiators as well as 50 Ω step fed has been introduced. The proposed UWB MIMO antenna has been evolved from recent peer published papers that provide WLAN notch (5.15‐5.85GHz), ultra wide band width (3.1‐10.6 GHz) and again a very good isolation (?20 dB) also maintained. In this paper the evolutions have been derived from antenna‐A to antenna‐E. The Ultra wide band is achieved by using step feed line, cutting a metal strip on a partial ground plane, a rectangular slot underneath the feed line of each radiator in antenna‐E. A high isolation (?20 dB) is obtained by introducing two inverted Г shaped stubs in the ground plane. Both antenna‐D and antenna‐E maintain high isolation (?20 dB). But antenna‐E performs better isolation compared to antenna‐D. The notch at WLAN band (5.15‐5.85GHz) is achieved by etching rectangular C‐shaped slot on the both the radiators. In antenna‐E two radiators are placed horizontally where as in antenna‐D two radiators placed orthogonally. It has been observed that the dimension of final outcome (antenna‐E) is reduced by 33% compared to antenna‐D without compromising the overall performance of the antenna. 相似文献
486.
Mallick Monalisa Mohanta Abinash Kumar Awadhesh Patra Kanhu Charan 《Building Simulation》2020,13(2):401-418
Building Simulation - Wind surface mean pressure coefficient (C?p) is an essential parameter for the assessment of wind induced forces that is a must input to all structural designs. An... 相似文献
487.
Faisal Nissar Malik Chinmoy Kolay 《The Structural Design of Tall and Special Buildings》2023,32(7):e2003
Tall buildings suffer from low inherent damping and high flexibility. Therefore, a core-outrigger system is often used to stiffen such buildings. A modified form, known as the damped outrigger system, wherein vertically oriented dampers are installed between outriggers and perimeter columns, has been recently developed to supplement the damping. This paper studies the efficacy of a viscously damped outrigger system through dynamic analysis of a 60-story tall building subjected to nonconcurrent earthquake and wind excitations. Two ground motion sets (100 accelerograms) are used for the former and wind tunnel test data for the latter. Effects of three building parameters, namely, (i) the core-to-column stiffness ratio, (ii) the outrigger location, and (iii) the damper size, on the dynamic characteristics and seismic and wind responses are evaluated. Effects of damper nonlinearity on seismic and wind responses are also investigated considering energy-equivalent nonlinear viscous dampers. Finally, the optimum values of these parameters are determined. For example, the optimum outrigger location is found to be between to , where is the height of the building. The results also show that the damped outrigger system significantly outperforms the conventional one for seismic excitation, and it is very effective in reducing the wind-induced floor accelerations, provided the parameters are chosen appropriately. 相似文献
488.
Chinmoy Mukherjee Lin Liu Nicola L. B. Pohl 《Advanced Synthesis \u0026amp; Catalysis》2014,356(10):2247-2256
The combination of benzyl bromide, sodium hydroxide and 15‐crown‐5 in tetrahydrofuran is shown to be an efficient method for installing benzyl groups at both the 4‐ and 6‐positions regioselectively directly from peracetylated N‐trichloroacetyl‐protected glucosamine and galactosamine. Application of this benzylation strategy proved to significantly shorten the synthetic route to hyaluronic acid tetra‐ and hexamers.