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排序方式: 共有531条查询结果,搜索用时 15 毫秒
151.
Manickam Sasidharan Nanda Gunawardhana Masaki Yoshio Kenichi Nakashima 《Materials Research Bulletin》2012,47(9):2161-2164
Nb2O5 hollow nanospheres of average diameter ca. ~29 nm and hollow cavity size ca. 17 nm were synthesized using polymeric micelles with core–shell–corona architecture under mild conditions. The hollow particles were thoroughly characterized by transmission electron microscope (TEM), X-ray diffraction (XRD), infrared spectroscopy (FTIR), thermal (TG/DTA) and nitrogen adsorption analyses. Thus obtained Nb2O5 hollow nanospheres were investigated as anode materials for lithium ion rechargeable batteries for the first time. The nanostructured electrode delivers high capacity of 172 mAh g?1 after 250 cycles of charge/discharge at a rate of 0.5 C. More importantly, the hollow particles based electrodes maintains the structural integrity and excellent cycling stability even after exposing to high current density 6.25 A g?1. The enhanced electrochemical behavior is ascribed to hollow cavity coupled with nanosized Nb2O5 shell domain that facilitates fast lithium intercalation/deintercalation kinetics. 相似文献
152.
Effect of iron (Wt.%) on adhesive wear response of Al-12Si-1Cu-0.1Mg alloy in dry sliding conditions
Mohit Dhiman D. K. Dwivedi Rakesh Sehgal I. K. Bhat 《Transactions of the Indian Institute of Metals》2008,61(6):451-456
The presence of iron leads to different types of intermetallics in Al-Si alloys, among them needle shaped β-phase (Al5FeSi) can lead to variations in hardness of the Al-Si alloy which ultimately can affect the wear resistance of the alloy.
In this paper, the effect of iron on wear behavior of cast Al-Si alloys has been reported. Sliding wear behavior of eutectic
alloy Al-12Si-1Cu-0.1Mg was investigated in dry sliding conditions by using pin-on-disk test configuration against heat treated
EN31 steel counter-surface at room temperature. Sliding wear behavior has been evaluated at four normal loads of 5, 20, 50
and 70 N and two sliding speeds, 2 m/s and 4 m/s. Worn pin surfaces were examined by scanning electron microscopy (SEM) for
analyzing wear mechanisms. The wear mechanism has been found to be mild oxidative type at lower sliding speed of 2m/s for
entire range of loads used in the study. Transition to severe metallic wear occurs at higher sliding speed of 4 m/s at normal
load of 5 N. Hardness of the alloy increased with increase in iron addition primarily due to presence of needle shaped Fe-rich
intermetallics but it leads to an increased wear rate. 相似文献
153.
Pattern Analysis and Applications - In this paper, a subsequence time-series clustering algorithm is proposed to identify the strongly coupled aftershocks sequences and Poissonian background... 相似文献
154.
Sarmistha Nanda Chhabi Rani Panigrahi Bibudhendu Pati 《International Journal of Communication Systems》2023,36(12):e4619
Among today's rapidly evolving technologies, artificial intelligence plays a significant role in making decisions by a system without any human intervention. An Emergency Management System (EMS) is a decision support system where emergencies such as tsunami, landslide, fire, cyclone, and electrical short circuits can be prevented with prior detection and can be addressed immediately in an efficient way after the emergency occurred. Automation of EMS can avoid or manage multiple emergencies, which alternatively can save lives, economy, and environment. Quality demand response with fast data transfer, error minimized computation, and effective resource utilization is very much essential while developing the EMSs. This will provide a bridge between the technology and emergency responders. Resource-limited smart devices can be made rich in computational behavior by outsourcing their requirements such as storage, virtual servers, and web services using Mobile Cloud Computing (MCC). In this work, we have done a detailed survey on both MCC applications and EMS applications proposed in the literature, and we have also identified the design challenges handled in both MCC and EMS applications. We have presented the design challenges and possible solutions for development of EMS using MCC. We propose an architecture for building an automated EMS using MCC. Finally, we conclude the paper with specific future directions. 相似文献
155.
Kotary Dinesh Kumar Nanda Satyasai Jagannath 《Wireless Personal Communications》2021,120(4):2545-2560
Wireless Personal Communications - Wireless sensor networks (WSNs) are inclusive of tiny sized battery dependent autonomous gadgets which are deployed in the decentralized manner in order to... 相似文献
156.
Multimedia Tools and Applications - Dental caries is one of the oral diseases which are a major health problem for many people across the globe. It can lead to pain, discomfort, disfigurement, and... 相似文献
157.
Nazir Salman Price Brad Surendra Nanda C. Kopp Katherine 《Information Technology and Management》2022,23(3):193-211
Information Technology and Management - Agile development is known for efficient software development practices that enable teams to quickly develop software to cope with changing requirements.... 相似文献
158.
159.
160.
S. K. Jha P. Srivastava R. Pal Anjali H. K. Sehgal Hee Chul Lee O. P. Agnihotri B. B. Gong 《Journal of Electronic Materials》2003,32(8):899-905
Mercury cadmium telluride (Hg1?xCdxTe or MCT) has been commonly used in devices for infrared (IR) detection. For the optimum performance of the device, a compatible surface-passivation technology that provides long-term stability is required. Using x-ray photoelectron spectroscopy (XPS), the present study examines the effects on Hg0.8Cd0.2Te passivated with CdTe and ZnS undergoing baking in vacuum at temperatures typically used for dewar bakeout. Spectra recorded as a function of depth in both cases clearly show out-diffusion of Hg from the substrate toward the surface, even before the bakeout. On baking in vacuum, dramatic changes are observed in the ZnS/MCT case with complete loss of Hg from the sample up to the tested depth of more than 1,000 Å. Compositions of the HgCdTe matrix, formed after Hg out-diffusion, before and after the bakeout are also calculated at selected depths (from 250 Å to 700 Å), which is vital information from a device point of view, as it affects the bandgap of this narrow-band semiconductor. 相似文献