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排序方式: 共有603条查询结果,搜索用时 218 毫秒
1.
Mudavath Raju Bhukya Rajendra Naik Jeripotula Praneet Raj 《Journal of Computational Electronics》2021,20(3):1430-1438
Journal of Computational Electronics - In the nanoscale regime, carbon nanotubes (CNTs) are being considered as a future alternative interconnect material for traditional copper (Cu) wires in... 相似文献
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The present study deals with the estimation of toxic phorbol esters in Balanites aegyptiaca seed cake and to evaluate the performance and combustion characteristics of different blends of biodiesel in a diesel engine. The seeds were manually collected from arid regions of Rajasthan, India and the oil extracted from the powdered kernel with Solvent extraction process. The extracted oil processed by enzymatic catalytic reactions are carried out at optimum operating conditions such as the molar ratio of 8:1 (methanol:oil), reaction temperature at 40°C for 4?h reaction time and xylanase 1% based on oil weight. The total conversion rate of extracted oil to methyl ester by enzymatic reactions yields up to 98.3%. The toxic content of seed cake was determined by high-performance liquid chromatography (HPLC, Shimadzu). The performance and combustion parameters such as BP, BTE and CP decreased, whereas BSFC and DP increased with biodiesel blends. 相似文献
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M.J.P. Naik J. Debbarma M. Saha A. Bhargava 《Materialwissenschaft und Werkstofftechnik》2020,51(3):368-374
Nowadays, the synthesis of graphene/ graphene oxide from graphite precursor using oxidizing agents is the most common procedure, but the direct synthesis of graphene or graphene oxide from a non-graphitic carbonaceous material without using inert atmosphere is really a great challenge. Besides, the chemistry behind the development of graphitic structure from a non-graphitic material during the thermal heating is still not clearly understood. In this research work, three agrowaste materials viz. rice husk, sugarcane bagasse and newspaper were selected and subjected to pyrolysis in presence of trace amount of air. The continued heating at the optimum temperature has resulted in aromatization and condensation along with the oxidation within the cellulosic structure of the agrowaste, which finally resulted in the formation of graphene oxide nanoflakes directly. The mechanism of formation of graphene oxide from these agrowaste materials was studied, which suggested that any carbonaceous waste materials can be converted to graphene oxide by optimizing the thermal heating conditions. 相似文献
5.
Jhuma Debbarma M. Jaya Prakash Naik 《Fullerenes, Nanotubes and Carbon Nanostructures》2019,27(6):482-485
In recent years, graphene oxide (GO) and reduced graphene oxide (r-GO) are being produced using graphite powder as precursor material but the preparation of graphene derivatives from a non-graphitic material without an additional oxidizing agent has not been reported so far. In this work, an agrowaste namely sugarcane bagasse was subjected to pyrolysis at three different temperatures, bypassing the use of toxic chemicals and graphite as a precursor. The chemistry of the effect of temperature and time on the development of graphitic planes in a non-graphitic material was studied. The formation of nanosheets of GO suggested that aromatization and condensation of the glucose monomers might have taken place which led to the glycosidic bond formation, further converging into polyaromatic rings on pyrolysis. The GO was further reduced at 95?°C using thiourea which resulted in the formation of r-GO after 8?hrs. 相似文献
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Shear Plugging and Frictional Behaviour of Composites and Fabrics Under Quasi‐static Loading 下载免费PDF全文
Experimental studies are presented on the shear plugging and frictional behaviour of composites and fabrics under quasi‐static loading. The primary focus is on the effect of specimen thickness on quasi‐static shear plugging behaviour. In the present study, quasi‐static shear plugging and through‐the‐thickness frictional tests are carried out on three types of materials. The materials investigated are 2D plain weave E‐glass/epoxy, 2D plain weave T300 carbon/epoxy and 2D plain weave E‐glass fabric. Typical results on shear plugging strength and frictional behaviour are presented. Effect of specimen thickness on quasi‐static shear plugging behaviour is also investigated. 相似文献
9.
Nanduri V. Sudarsan Samir K. Das Smita D. Naik 《Propellants, Explosives, Pyrotechnics》2016,41(5):844-849
Determination of propellant formulation by ballistic requirement is an important area of research in recent times. In this study, a theoretical method for the design of gun propellant formulation using primary data of ingredients and necessary thermochemical properties of the resultant propellant was established. The employed method is based on a mathematical model of thermochemical properties of the propellant by optimizing the heat of explosion of the propellant using the fmincon tool in MATLAB. A graphical user interface (GUI) based code was generated and developed for the formulation design of solid gun propellants. The designed code was verified by available data in the literature. Such code will be useful to the researchers working in the area of high energy materials for the design of unknown propellant compositions. Further, it can be extended to redesign the existing propellant formulation in order to enhance the ballistic performance. 相似文献
10.
Fabien Paulot David Paynter Vaishali Naik Sergey Malyshev Raymond Menzel Larry W. Horowitz 《International Journal of Hydrogen Energy》2021,46(24):13446-13460
Hydrogen (H2) has been proposed as an alternative energy carrier to reduce the carbon footprint and associated radiative forcing of the current energy system. Here, we describe the representation of H2 in the GFDL-AM4.1 model including updated emission inventories and improved representation of H2 soil removal, the dominant sink of H2. The model best captures the overall distribution of surface H2, including regional contrasts between climate zones, when vd(H2) is modulated by soil moisture, temperature, and soil carbon content. We estimate that the soil removal of H2 increases with warming (2–4% per K), with large uncertainties stemming from different regional response of soil moisture and soil carbon. We estimate that H2 causes an indirect radiative forcing of 0.84 mW m?2/(Tg(H2)yr?1) or 0.13 mW m?2 ppbv?1, primarily due to increasing CH4 lifetime and stratospheric water vapor production. 相似文献