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991.
Multimedia Tools and Applications - Improving quality of experience (QoE) is increasingly significant for Internet video content providers. The essential issue is how to evaluate QoE under the... 相似文献
992.
Lin Yueming Su Siyu Wang Rui Dai Huimin Lai Liuqin Jiang Yue Zhu Xiaohong 《Journal of Materials Science: Materials in Electronics》2021,32(22):26688-26699
Journal of Materials Science: Materials in Electronics - With the advantages of high power density, long cycle life, and fast charging, supercapacitor has become a research hotspot in recent... 相似文献
993.
Guo Liang Goh Jiaheng Ma Kwee Lim Francis Chua Agarwala Shweta Yue Ping Zhang 《Virtual and Physical Prototyping》2016,11(4):289-294
This research focuses on exploring low-cost and rapid production solutions for fabricating emitters for patch antennas for wireless communication applications. Additive manufacturing technique is employed to fabricate two patch antennas using silver nanoparticle ink on FR4 substrate. Finite-element simulation software, HFSS is used to analyse and predict the theoretical performance of the antenna designs for 2.4?GHz MIMO and 6?GHz wireless data transmission. The fabricated antennas have resonant frequencies closely matching the design values. The work provides a viable solution for fabricating emitters and finally antennas commercially using inkjet printing platform, thus overall reducing the cost and simplifying the process. 相似文献
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995.
Construction and optimization of trans‐4‐hydroxy‐L‐proline production recombinant E. coli strain taking the glycerol as carbon source 下载免费PDF全文
996.
Zhixun Wen Huanze Mao Zhufeng Yue Baizhi Wang 《Journal of Materials Engineering and Performance》2014,23(2):372-377
Modeling of a nickel-base single crystal superalloy turbine blade which accounts for material orthotropy is carried out to investigate the influence of axial direction and randomness crystallographic orientation on the dynamic natural frequency. In this paper, the natural frequency of the blade is calculated by the finite element method based on the commercial software ABAQUS. The results show that the deviation of the axial directions has a significant effect on the lower frequency as well as on the higher frequency, while the randomness in crystallographic orientations has a great impact only on higher order frequency. It is necessary to take the crystal orientation into account as an optimized factor and the variation of the vibration characteristics can be predicted. 相似文献
997.
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999.
Wen Qian JiaoMing Bo Yue Yi Meng Wang Ming-Yuan He 《Microporous and mesoporous materials》2012,147(1):167-177
Aluminum hydroxides were synthesized through the acidification of sodium aluminate solution using single organic diester or diacid as pH adjustor and aluminum chelating agent. The obtained alumina hydrates are investigated by XRD, SEM, IR and TG. Bayerite firstly formed at room temperature, and its morphology greatly varied with the pH adjustors used, which probably attributes to different kinetics of the acidification. The bayerite can evolve to gibbsite and boehmite after the hydrothermal treatment at 100 °C and 145 °C, respectively, where these alumina hydrates show diverse morphologies. After the calcination, these alumina hydrates of bayerite, gibbsite and boehmite could pseudomorphically transform to the corresponding η-, χ- and γ-aluminas, respectively, exhibiting different structural and textural properties. Interestingly, the transition aluminas derived from the aluminum tri-hydroxides, bayerite and gibbsite, both display locally organized mesopores, while no such meso-structure can be observed in γ-alumina obtained from the aluminum mono-hydroxide, boehmite. The changes of bayerite during calcination are investigated detailed. The dehydration of non-porous bayerite accompanied with the formation of meso-structured transition aluminas, where the meso-structure becomes more and more clearly defined and pore size expands with the calcination temperature increasing. 相似文献
1000.