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排序方式: 共有505条查询结果,搜索用时 125 毫秒
71.
Geleta Dereje Degefa Siddiqui Md Irfanul Haque Lee Joonho 《Metallurgical and Materials Transactions B》2020,51(1):102-113
Metallurgical and Materials Transactions B - The static and dynamic holdups of liquid slag flow in a packed coke bed were investigated at a temperature of 1723 K by using the... 相似文献
72.
Md Azimul Haque Appala Naidu Gandi Rajeshkumar Mohanraman Yakui Weng Bambar Davaasuren Abdul‐Hamid Emwas Craig Combe Derya Baran Alexander Rothenberger Udo Schwingenschlgl Husam N. Alshareef Shuai Dong Tom Wu 《Advanced functional materials》2019,29(13)
Organic–inorganic hybrid materials are of significant interest owing to their diverse applications ranging from photovoltaics and electronics to catalysis. Control over the organic and inorganic components offers flexibility through tuning their chemical and physical properties. Herein, it is reported that a new organic–inorganic hybrid, [Mn(C2H6OS)6]I4, with linear tetraiodide anions exhibit an ultralow thermal conductivity of 0.15 ± 0.01 W m?1 K?1 at room temperature, which is among the lowest values reported for organic–inorganic hybrid materials. Interestingly, the hybrid compound has a unique 0D structure, which extends into 3D supramolecular frameworks through nonclassical hydrogen bonding. Phonon band structure calculations reveal that low group velocities and localization of vibrational energy underlie the observed ultralow thermal conductivity, which could serve as a general principle to design novel thermal management materials. 相似文献
73.
Wireless Networks - Currently, IEEE 802.11 standard for ad-hoc wireless mode is inadequate for multi-hop network. Recent efforts for the advancement of 802.11 standards, such as 11e for QoS support... 相似文献
74.
In this work, antenna miniaturization using slits and metallic strips fed by microstrip line has been demonstrated. It has been noticed that slot antenna fed by microstrip line provides more miniaturization and in some cases enhanced bandwidth in comparison with the slot antenna fed by other feeding mechanism, keeping the same length and width of the radiating slots, slits and metallic strips. We have achieved 51.67% reduction in resonant frequency and 74.72% improvement in ?10 dB bandwidth compared with 37.73% and no bandwidth improvement of either side slits loaded slot antenna topology. Further, it has been shown 63.52% reduction in resonant frequency and 2.23% improvement in ?10 dB bandwidth in comparison with 42.33% reduction in resonant frequency of only one side slits loaded slot antenna topology. The current work highlighted not only greater miniaturization and enhanced bandwidth but also almost unperturbed radiation pattern compared to reference antenna topology and low cross‐pol level even slot antenna loaded by only one side slits, which was not demonstrated in earlier works. 相似文献
75.
Solar Cells: Overcoming the Ambient Manufacturability‐Scalability‐Performance Bottleneck in Colloidal Quantum Dot Photovoltaics (Adv. Mater. 35/2018)
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77.
Jafri Syed Rehan Abbas Hamid Tehreem Mahmood Rabia Alam Muhammad Asjad Rafi Talha Ul Haque Muhammad Zeeshan Munir Muhammad Wasim 《Wireless Personal Communications》2019,106(4):2163-2177
Wireless Personal Communications - The number of aged and disabled people has been increasing worldwide. To look after these people is a big challenge in this era. However, scientists overcome the... 相似文献
78.
The apparent analogy between nucleate boiling and electrolytic gas bubble evolution has prompted a study of the latter in an attempt to clarify the similarity between the limiting rate processes in the two. For the case of electrolytic evolution of hydrogen bubbles from a platinum electrode in sulfuric acid, measurements of simultaneous instantaneous bubble growth rates and electrode currents under limiting current conditions are shown to be consistent with the combination of atomic to molecular hydrogen on the surface as the rate limiting step. As there is no analogous mechanism in nucleate boiling, it is concluded that extreme caution should be exercised in postulating a general analogy between the two phenomena. 相似文献
79.
Melt compounded nanocomposites with semi‐interpenetrated network structure based on natural rubber,polyethylene, and carrot nanofibers
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The present study deals with the processing and characterization of cellulose nanocomposites natural rubber (NR), low‐density polyethylene (LDPE) reinforced with carrot nanofibers (CNF) with the semi‐interpenetrated network (S‐IPN) structure. The nanocomposites were compounded using a co‐rotating twin‐screw extruder where a master‐batch of NR and CNF was fed to the LDPE melt, and the NR phase was crosslinked with dicumyl peroxide. The prepared S‐IPN nanocomposites exhibited a significant improvement in tensile modulus and yield strength with 5 wt % CNF content. These improvements are due to a better phase dispersion in the S‐IPN nanocomposites compared with the normal blend materials, as demonstrated by optical microscopy, electron microscopy and ultraviolet–visible spectroscopy. The S‐IPN nanocomposite also displayed an improved crystallinity and higher thermal resistance compared with NR, CNF, and the normal blend materials. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45961. 相似文献
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