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排序方式: 共有386条查询结果,搜索用时 15 毫秒
381.
Metallurgical and Materials Transactions A - The dissimilar metal joining of stainless steel (SS)/copper (Cu) was done cost-effectively with Gas Tungsten Arc Welding (GTAW). A combination of...  相似文献   
382.
Shankar  S.  Nithyaprakash  R.  Abbas  G.  Naveenkumar  R.  Prakash  Chander  Pramanik  Alokesh  Basak  Animesh Kumar 《SILICON》2023,15(2):983-991
Silicon - The use of magnesium alloy (AZ31) has profound applications in biomedical field as a substitute for joint replacements. The present study aims at analyzing the tribological behavior of...  相似文献   
383.
This study investigates the structures produced by blending ligno-cellulosic (ramie fibre, Boehmeria nivea L.) and protein fibres (mulberry silk, Bombyx Mori) with dissimilar mechanical properties. Ramie fibre, used for blending, is a ligno-cellulosic fibre with very high tenacity but low elongation. On the other hand, silk (mulberry) fibre has lower tenacity with better elongation. Blended fibrous structures have shown satisfactory tensile strength and elongation, while other physical properties, such as coefficient of friction, brightness and flexural rigidity, have also been improved. Technical findings revealed that the coefficient of friction reduced from 0.79 to 0.48 and specific work of rupture improved from 2.3 to 3.43 mJ/tex after incorporation of silk in the ligno-cellulosic fibre strand. Blended yarn cross-sectional images showed that finer silk fibres came to the surface, whereas the comparatively coarser cellulose-based ramie fibre migrated to the core. Atomic force microscopy of the blend structure was examined to assess the roughness and uniformity of the surface. Fourier Transform–infrared spectroscopy analysis verified the presence of amide groups (associated with silk fibre) and glucose ring groups (associated with the cellulose of Ramie fibre) in the same graph. In addition, innovative techniques of simultaneous coloration of the developed blends are also proposed scientifically.  相似文献   
384.
The past decade has marked a renewed interest in borazines and BN-doped polycyclic aromatic hydrocarbons. This is predominantly because of new advances that have highlighted their potential in various applications, including gas separation and storage, organic (opto)electronics, catalysis, and as supramolecular systems. This review gives a critical overview of the most significant approaches to the synthesis of (substituted) B3N3 motifs and focuses on the discussion of those borazine-doped carbon structures that have been developed for potential use in materials science applications.  相似文献   
385.
Basak  Arighna  Sarkar  Angsuman 《SILICON》2022,14(1):75-86
Silicon - This paper presents the continuous 2D analytical modelling of electrostatic potential, threshold voltage (Vth), subthreshold swing, drain induced barrier lowering (DIBL) and drain current...  相似文献   
386.
The sluggish redox kinetics and shuttle effect seriously impede the large application of room-temperature sodium–sulfur (RT Na–S) batteries. Designing effective catalysts into cathode material is a promising approach to overcome the above issues. However, considering the multistep and multiphase transformations of sulfur redox process, it is impractical to achieve the effective catalysis of the entire S8→Na2Sx→Na2S conversion through applying a single catalyst. Herein, this work fabricates a nitrogen-doped core–shell carbon nanosphere integrated with two different catalysts (ZnS-NC@Ni-N4), where isolated Ni–N4 sites and ZnS nanocrystals are distributed in the shell and core, respectively. ZnS nanocrystals ensure the rapid reduction of S8 into Na2Sx (4 < x ≤ 8), while Ni–N4 sites realize the efficient conversion of Na2Sx into Na2S, bridged by the diffusion of Na2Sx from the core to shell. Besides, Ni–N4 sites on the shell can also induce an inorganic-rich cathode–electrolyte interface (CEI) on ZnS-NC@Ni-N4 to further inhibit the shuttle effect. As a result, ZnS-NC@Ni-N4/S cathode exhibits an excellent rate-performance (650 mAh g−1 at 5 A g−1) and ultralong cycling stability for 2000 cycles with a low capacity-decay rate of 0.011% per cycle. This work will guide the rational design of multicatalysts for high-performance RT Na–S batteries.  相似文献   
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