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排序方式: 共有1905条查询结果,搜索用时 15 毫秒
71.
72.
Das Ashmi Chakraborty Dwari Santanu Bage Amit 《Wireless Personal Communications》2018,98(4):3477-3503
Wireless Personal Communications - This paper presents method of moment based analysis of E Plane and H-Plane T-junctions to find the field distributions on different transverse and longitudinal... 相似文献
73.
Amit Md. Estiaque Arefin Md. Tariqul Islam Md. Shamim Akhter 《The International journal of environmental studies》2018,75(5):732-739
Today, urbanised people spend most of their time in indoor environments, and the risk of exposure to toxic materials in an indoor environment is of great concern. This paper considers sources for the inhalation risk of aerosol sprays by measuring the particle size distributions of some of the most popular products that are commercially available in Bangladesh, and examines the degree of toxicity and the health risk via the respirability of the products. Results show that thoracic and respirable fractions of the suspended particulate matter are present in the tested samples and hence the spray products may pose a significant health risk. 相似文献
74.
A flower‐shaped ultra‐wideband fractal antenna is presented. It comprises a fourth iterative flower‐shaped radiator, asymmetrical stub‐loaded feeding line, and coplanar quarter elliptical ground planes. A wide operating band of 12.12 GHz (4.58‐16.7 GHz) for S 11 ≤ ? 10 dB is achieved along with an overall antenna footprint of 15.7 × 11.4 mm2. In addition, other desirable characteristics, that is, omnidirectional radiation patterns, peak gain upto 5 dB, and fidelity factor more than 75% are achieved. A good agreement exists between the simulation and measured results. The obtained results illustrate that this antenna has wide operating range and compact dimensions than available structures. 相似文献
75.
76.
Soumya Ghosh Chowdhury Jagannath Chanda Sreedip Ghosh Koushik Banerjee Shib Shankar Banerjee Amit Das Prasenjit Ghosh Sanjay Kr. Bhattacharyya Rabindra Mukhopadhyay 《Polymer Engineering and Science》2020,60(8):1973-1983
Proficiency on underlying mechanism of rubber-metal adhesion has been increased significantly in the last few decades. Researchers have investigated the effect of various ingredients, such as hexamethoxymethyl melamine, resorcinol, cobalt stearate, and silica, on rubber-metal interface. The role of each ingredient on rubber-metal interfacial adhesion is still a subject of scrutiny. In this article, a typical belt skim compound of truck radial tire is selected and the effect of each adhesive ingredient on adhesion strength is explored. Out of these ingredients, the effect of cobalt stearate is found noteworthy. It has improved adhesion strength by 12% (without aging) and by 11% (humid-aged), respectively, over control compound. For detailed understanding of the effect of cobalt stearate on adhesion, scanning electron microscopy and energy dispersive spectroscopy are utilized to ascertain the rubber coverage and distribution of elements. X-ray photoelectron spectroscopy results helped us to understand the impact of CuXS layer depth on rubber-metal adhesion. The depth profile of the CuXS layer was found to be one of the dominant factors of rubber-metal adhesion retention. Thus, this study has made an attempt to find the impact of different adhesive ingredients on the formation of CuXS layer depth at rubber-metal interface and establish a correlation with adhesion strength simultaneously. 相似文献
77.
Sadiya Waseem Priyanka H. Maheshwari Sankaran Abinaya Akhila K. Sahu Amit Saini Sanjay R. Dhakate 《国际能源研究杂志》2019,43(7):2897-2909
Porous conducting carbon fiber‐based composite paper is used as an electrode backing in the fuel cell assembly. It not only acts as a channel through which the reactant and product gases pass to and from the bipolar plate and the catalyst site but also helps in the flow of electrons. In order to perform its role efficiently, it should have sufficient strength, high electrical conductivity, and ideal porous structure. Carbon paper has been fabricated, which builds up the required composite properties. Studies have been conducted to optimize the fiber/matrix ratio in the carbon paper, while ensuring the perfect combination of porosity, mechanical strength, and electrical conductivity for an electrode in a proton electrolyte membrane fuel cells. Detail physico‐mechanical and electrochemical characterizations further ascertain that the fiber/matrix ratio plays an important role in tuning the composite properties. The polarization curve of the unit proton exchange membrane (PEM) fuel cell (with an effective electrode area 4 cm2) shows a peak power density of 916 mW/cm2 for the sample with fiber/matrix ratio of 65:35, which is almost the same as the commercially available sigracet gas diffusion layer (SGL) carbon paper tested under similar conditions. Further, proportionally enlarging the electrode area to 100 cm2 shows that the carbon paper not only shows almost repeatable results in a given set up but also scales up. 相似文献
78.
Vegetable oils are now considered to be a potential alternative that can be used in place of partial or total substitution of diesel fuels. In this study, we used diethyl ether as an oxygenated additive to investigate the possible use of higher percentages of biodiesel in an unmodified diesel engine. Neem oil was selected for biodiesel production. The tests were performed at a steady-state condition in a single-cylinder constant speed DI diesel engine. The combustion process involved in diesel engine would be improved and the particulate matter would be reduced if these biodiesels are blended. An experimental investigation is carried out to establish the emission characteristics of a direct injection diesel engine using diethyl ether as additive in Neat Neem oil Biodiesel. Emissions of hydro carbon oxides of nitrogen and carbon monoxide significantly reduced by adding diethyl ether into neem oil biodiesel at 10% and 20% on volume basis. 相似文献
79.
Singh A. K. Chandra Devesh Kattayat Sandhya Kumar Shalendra Alvi P. A. Rathi Amit 《Semiconductors》2019,53(12):1584-1592
Semiconductors - Compositional variations in GaAs based ternary alloys have exhibited wide range alterations in electronic properties. In the present paper, first-principles study of... 相似文献
80.
Mukherjee Tanmay Singh Amit Kumar Senapati Dilip 《Wireless Personal Communications》2019,106(2):789-803
Wireless Personal Communications - In wireless communication channels, the signals arriving at the receiver may be of stochastic nature or be superpositioned due to non-uniform scattering and... 相似文献