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排序方式: 共有927条查询结果,搜索用时 15 毫秒
1.
Kumar S. Ganesh Sridhar S. S. Hussain Azham Manikanthan S. V. Padmapriya T. 《Multimedia Tools and Applications》2022,81(7):9091-9109
Multimedia Tools and Applications - Discovering the relevant web services for specific applications in the dynamically changing business world becomes very critical. Researchers have used many... 相似文献
2.
Darothi Bairagi Venkataramana Munukuti Pallabi Bhuyan Rajib Saha Sumantra Mandal 《工业材料与腐蚀》2021,72(5):829-838
The influence of cementite spheroidization on the impact toughness and electrochemical properties of a high-carbon steel has been thoroughly investigated in this study. Heavy warm rolling, followed by 2 h of annealing, has resulted in near-complete spheroidization, leading to a microstructure consisting of nano-cementite globules dispersed in the ultrafine-grained ferritic matrix. The Charpy impact test exhibited superior impact toughness with increased spheroidization. It is validated by the presence of abundant dimples in the fractographs of spheroidized specimens, in contrast to the as-received one that experienced a brittle failure due to its lamellar pearlitic structure. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) carried out in a 3.5% NaCl solution revealed that the corrosion resistance of the alloy gets improved with the increase in the degree of spheroidization. This is attributed to the lower susceptibility of the spheroidized specimen to microgalvanic corrosion owing to the minimum area of contact between nano-spheroidized cementite and ferrite, as elucidated with the help of EIS results aided by equivalent electrical circuit model. 相似文献
3.
Hui Liu Shuang Dai Jun Li Rui Ma Yan Cao Gang Wang Sridhar Komarneni Jianhong Luo 《化学工程与技术》2020,43(5):974-982
The very good extraction selectivity of Cu2+ from water was demonstrated with a new microchannel equipment, by employing di-(2-ethylhexyl)phosphoric acid (D2EHPA) as an extractant and kerosene as a solvent. The effects of different experimental parameters on the extraction efficiency E, the volumetric mass transfer coefficient KLa, and the entrainment were experimentally investigated. The results showed that the extraction efficiency increased with increasing temperature, extractant concentration, phase ratio (organic/aqueous), and pH. The total flow rate, phase ratio, and pH were found to have a great effect on the mass transfer, whereas the temperature and the extractant concentration showed little effect. 相似文献
4.
Kasarapu Venkataramana Chittimadula Madhuri Ch Madhusudan Y.Suresh Reddy G. Bhikshamaiah C.Vishnuvardhan Reddy 《Ceramics International》2018,44(6):6300-6310
In the present study, we investigate the fundamental properties of CeO2 by selecting La3+ (57), and Dy3+ (66) as dopants with optimized average atomic number of 61.5, which lies in between Pm3+ (62) and Sm3+ (62) in accordance with the criteria for optimum doping. A system of co-doped ceria ceramics Ce1–x–yLaxDyyO2-δ ((x, y) = (0.00, 0.00), (0.025, 0.025), (0.05, 0.05), (0.075, 0.075), (0.10, 0.10), (0.00, 0.20) and (0.20, 0.00)) as electrolytes for intermediate temperature solid oxide fuel cells were successfully prepared by a well-known sol-gel auto-combustion route. In order to obtain dense samples, the prepared pellets were sintered in air at 1300 °C for 4 h using conventional furnace and relative densities of all the samples were found to be higher than 95%. Single phase cubic structure, microstructural density and elemental composition analysis of all the samples were studied by powder X-ray diffraction, scanning electron microscope and energy dispersive spectroscopy techniques, respectively. Raman spectroscopy analysis confirmed the formation of concentrated O2-–vacancies in the co-doped ceria system. Impedance spectroscopy measurements revealed the high value of total ionic conductivity and low activation energy for the composition Ce0.85La0.075Dy0.075O2?δ i.e., 2.08 × 10–2 S cm–1 and 0.58 eV, respectively. Linear thermal expansion analyses of all the samples revealed the matched thermal expansion coefficients. Finally, these results recommend that the Ce0.85La0.075Dy0.075O2?δ sample can be useful as a solid electrolyte in IT-SOFC applications. 相似文献
5.
Tarun Sai Ghanta Sridhar Aparna Namrata Verma Doddipatla Purnima 《Polymer Engineering and Science》2020,60(8):1717-1759
Polyamide 6 (PA6)-based composites are of evolving interest due to its high strength, wear resistance, and barrier properties. The use of binary composites mostly with nanomaterial and glass fibers has been reviewed and presented in literature. However to obtain a balance of properties like stiffness, toughness, and strength along with cost reduction, ternary composites of PA6 have been designed. To achieve the balance, PA6 blend-based composites, with combination of microfiller/nanofiller or PA6 with combination micro-microfiller, PA6 with microfiller/nanofiller and fiber have been designed. The properties of PA6-based ternary hybrid composites depend on type of dispersed phase used, presence of compatibilizer, type of filler used (nanofiller or microfiller or fiber or hybrid) and combination of fillers used. However, a review in this direction is not available in literature. Here, in this study, an overall understanding of various fillers, dispersed phase, and their combinations can be understood along with the discussion on effect of these on tensile properties and morphology of hybrid composite. In this study, an attempt has been made to review the various fillers and dispersed phase and their combinations which have been used in designing the PA6 hybrid composite with good balance of stiffness, toughness, and strength. 相似文献
6.
7.
Sridhar Dalai Vijayalakshmi Savithri Pragya Shrivastava Santosh Param Sivam Pratibha Sharma 《国际能源研究杂志》2015,39(5):717-726
The greatest challenge for a feasible hydrogen economy lies on the production of pure hydrogen and the materials for its storage with controlled release at ambient conditions. Hydrogen with its great abundance, high energy density and clean exhaust is a promising candidate to meet the current global challenges of fossil fuel depletion and green house gases emissions. Extensive research on hollow glass microspheres (HGMs) for hydrogen storage is being carried out world‐wide, but the right material for hydrogen storage is yet underway. But many other characteristics, such as the poor thermal conductivity etc. of the HGMs, restrict the hydrogen storage capacity. In this work, we have attempted to increase the thermal conductivity of HGMs by ZnO doping. The HGMs with Zn weight percentage from 0 to 10 were prepared by flame spheroidization of amber‐colored glass powder impregnated with the required amount of zinc acetate. The prepared HGMs samples were characterized using field emission‐scanning electron microscope (FE‐SEM), environmental SEM (ESEM), high‐resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy and X‐ray diffraction (XRD) techniques. The deposition of ZnO on the microsphere walls was observed using FE‐SEM, ESEM and HRTEM which was further confirmed using the XRD and ultraviolet–visible absorption data. The hydrogen storage studies done on these samples at 200 °C and 10‐bar pressure for 5 h showed that the hydrogen storage increased when the Zn percentage in the sample increased from 0 to 2%. The percentage of zinc beyond 2, in the microspheres, showed a decline in the hydrogen storage capacity. The closure of the nanopores due to the ZnO nanocrystal deposition on the microsphere surface reduced the hydrogen storage capacity. The hydrogen storage capacity of HAZn2 was found 3.26 wt% for 10‐bar pressure at 200 °C. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
8.
9.
Kandi Sridhar Albert Linton Charles 《International Journal of Food Science & Technology》2021,56(4):1937-1945
Grape (Kyoho) skin, used to retard lipid oxidation in edible oil foods, was investigated to reduce lipid oxidation in an oil-in-water (O/W) emulsion during 20 day of storage. The antioxidant efficacy of Kyoho skin extracts in O/W emulsions was determined by the measurement of secondary oxidation products. Moreover, principal component analysis (PCA) was conducted to determine similarities between emulsions treated with or without Kyoho skin extracts and standards. The data revealed that Kyoho skin extracts exhibited >93% inhibition and reported a similar p-anisidine (4.30–20.71) and TBARS (6.08–11.15 mg MDA L−1) values over the standards during 20 day of storage. PCA (PCs 1 (51.83%) and 2 (18.85%)) demonstrated a similarity in the contribution of Kyoho skin extracts over the synthetic antioxidants in O/W emulsion. Overall, these findings highlighted the possibility of using Kyoho skin extracts as natural antioxidants to decrease oxidative rancidity in foods. 相似文献
10.
Membrane separation methods such as electrodialysis (ED) can reduce the volume load on evaporators by facilitating further concentration of rejects from reverse osmosis (RO) plants. ED studies were carried out on a bench-scale system using five membrane cell pairs to obtain a textile effluent concentrate containing approximately 6 times the quantity of salts present in the RO reject. The limiting current densities were determined to be in the range 2.15–3.35 amp/m2 for feed flow rates varying from 18 to 108 L/h. Apart from feed rate, the influence of volume of concentrate and current on membrane performance was evaluated to optimize current utilization. An estimation of energy requirement of an integrated process constituting ED and evaporation for concentration of inorganics present in textile effluent from 4.35% to 24% was made and found to be approximately one eighth of the operating cost incurred by evaporation alone. Detailed design of a commercial ED system revealed that a membrane area of 13.1 m2 was required to treat a feed rate of 1500 L/h. The payback period to recover capital investment was found to be 110 days. 相似文献