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排序方式: 共有1211条查询结果,搜索用时 15 毫秒
21.
Xuejiao Liu Zhixin Xu Asma Iqbal Ming Chen Nazakat Ali CheeTongJohn Low Rongrong Qi Jiantao Zai Xuefeng Qian 《纳微快报(英文)》2021,(3):197-208
Huge volume changes of Si during lithiation/delithiation lead to regeneration of solid-electrolyte interphase(SEI)and consume electrolyte.In this article,γ-glycidoxypropyl trimethoxysilane(GOPS)was incorporated in Si/PEDOT:PSS electrodes to construct a flexible and conductive artificial SEI,effectively suppressing the consumption of electrolyte.The optimized electrode can maintain 1000 mAh g^−1 for nearly 800 cycles under limited electrolyte compared with 40 cycles of the electrodes without GOPS.Also,the optimized electrode exhibits excellent rate capability.The use of GOPS greatly improves the interface compatibility between Si and PEDOT:PSS.XPS Ar+etching depth analysis proved that the addition of GOPS is conducive to forming a more stable SEI.A full battery assembled with NCM 523 cathode delivers a high energy density of 520 Wh kg^−1,offering good stability. 相似文献
22.
The static and dynamic coefficient of friction between two flat surfaces at elevated temperature is under investigation. The equipment used in this study was originally designed for the precision glass molding (PGM) process and was then modified for friction measurement. The ultimate aim of this research is to study and characterize the frictional behavior between glass and a mold surface at elevated temperatures typical of the PGM process and under conditions similar to those for this process. This paper describes the design of the apparatus, and validation experiments using a steel-steel material pair at room temperature for comparison with values reported in the literature. The average friction coefficient between the steel-steel pair was found to be 0.17. Subsequent experiments using steel against steel and BK-7 glass against steel, found the stick-slip phenomena is happening at 577 °C. 相似文献
23.
Weiming Xiang Jian Xiao Muhammad Naveed Iqbal 《International Journal of Adaptive Control and Signal Processing》2012,26(4):350-373
In this paper, several concepts of switching frequency are introduced to analyze the properties and performance of switched systems in infinite as well as finite‐time intervals. The observation is very motivating that different system properties and performances depend on different switching frequencies. Sufficient conditions ensuring asymptotic stability, ?2 gain performance, and state boundness are derived on the basis of the notions of switching frequency, respectively. Then, on the basis of the analysis results, the control synthesis problems are addressed. LMI‐based design algorithms are proposed to meet different control synthesis requirements. Numerical design examples are provided to demonstrate our results. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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25.
Rapid and Nondestructive Identification of Polytypism and Stacking Sequences in Few‐Layer Molybdenum Diselenide by Raman Spectroscopy 下载免费PDF全文
26.
An improved strategy for skin lesion detection and classification using uniform segmentation and feature selection based approach 下载免费PDF全文
Muhammad Nasir Muhammad Attique Khan Muhammad Sharif Ikram Ullah Lali Tanzila Saba Tassawar Iqbal 《Microscopy research and technique》2018,81(6):528-543
Melanoma is the deadliest type of skin cancer with highest mortality rate. However, the annihilation in early stage implies a high survival rate therefore, it demands early diagnosis. The accustomed diagnosis methods are costly and cumbersome due to the involvement of experienced experts as well as the requirements for highly equipped environment. The recent advancements in computerized solutions for these diagnoses are highly promising with improved accuracy and efficiency. In this article, we proposed a method for the classification of melanoma and benign skin lesions. Our approach integrates preprocessing, lesion segmentation, features extraction, features selection, and classification. Preprocessing is executed in the context of hair removal by DullRazor, whereas lesion texture and color information are utilized to enhance the lesion contrast. In lesion segmentation, a hybrid technique has been implemented and results are fused using additive law of probability. Serial based method is applied subsequently that extracts and fuses the traits such as color, texture, and HOG (shape). The fused features are selected afterwards by implementing a novel Boltzman Entropy method. Finally, the selected features are classified by Support Vector Machine. The proposed method is evaluated on publically available data set PH2. Our approach has provided promising results of sensitivity 97.7%, specificity 96.7%, accuracy 97.5%, and F‐score 97.5%, which are significantly better than the results of existing methods available on the same data set. The proposed method detects and classifies melanoma significantly good as compared to existing methods. 相似文献
27.
Russian Journal of Non-Ferrous Metals - In this study, the micro-mechanisms involved in fatigue crack propagation are investigated qualitatively in a Al/Al2O3/SiC hybrid metal matrix composite... 相似文献
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Composites consisting of carbon fibers (CF) and carbon particles (CP) in polypropylene (PP) matrix were melt-compounded. Composites
were analyzed for their mechanical, electrical and thermal properties. Results indicate that the addition of these fillers
improved the mechanical properties of the composites. Thermal conductivity was enhanced as the concentration of fillers was
increased. Carbon fibers render the composites electrically conductive so we observed a percolation threshold near 10 wt.%
of CF for PP/CF (PP and CF composite) and near 25 wt.% of CP for PP/CP (PP and carbon particle composite). All the results
indicated that carbon fibers are more effective in improving the properties as compare to the carbon particles. 相似文献
30.
Yuanliang Zhang Zhimin Zhou Yan Lv Jinlong Wang Lei Shao Asif Iqbal 《The International Journal of Advanced Manufacturing Technology》2013,69(1-4):329-335
Natural diamond tool is quickly worn out while cutting a workpiece made of a tungsten-based alloy. This paper presents a new approach to reduce tool wear: ultrasonic vibration cutting of a workpiece made of a tungsten-based alloy based on gas–liquid atomization cooling. An atomizer is a device which mixes carbon dioxide gas with vegetable oil and changes the liquid into minute droplets, which are carried by a stream of gas. Atomizer is also a device that incorporates a venture device to translate liquid into a gas stream. The atomized minute droplets act as the cooling and lubricating medium to protect the tools. The system is designed to ensure that droplets can spread all over the surface of a work piece. At a constant spindle speed, feed rate, and cutting depth, the experiments were carried out for investigating the effects of the tool vibration parameters, carbon tetrachloride liquid flow rate, carbon dioxide gas flow, and gas–liquid mass ratio on the tool wear. The experiments showed that the technology of ultrasonic vibration with gas–liquid atomization cooling effectively prolongs the tool life in cutting tungsten-based alloy. 相似文献