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991.
992.
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
993.
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
994.
995.
996.
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
997.
998.
An information hiding algorithm is proposed, which hides information by embedding secret data into the palette of bitmap resources of portable executable (PE) files. This algorithm has higher security than some traditional ones because of integrating secret data and bitmap resources together. Through analyzing the principle of bitmap resources parsing in an operating system and the layer of resource data in PE files, a safe and useful solution is presented to solve two problems that bitmap resources are incorrectly analyzed and other resources data are confused in the process of data embedding. The feasibility and effectiveness of the proposed algorithm are confirmed through computer experiments. 相似文献
999.
Yinggao Yue Jianqing Li Hehong Fan Qin Qin Le Gu Li Du 《Wireless Personal Communications》2017,97(3):3277-3292
There exist several applications of wireless sensor networks in which the reliable operation can be crucial. Fault prediction is a critical problem in reliability theory for ribbon wireless sensor networks (RWSNs). Accurate fault prediction can effectively improve the availability of the WSNs system. In this paper, we evaluated the network performance for RWSNs, studied the basic theory of kernel functions, proposed a new failure prediction method based on kernel function, and selected the radial basis function as kernel function failure prediction models from two aspects of node hardware failures and network failures for fault prediction. Theoretical evidence and experimental results have shown that the proposed algorithmic prediction method has higher accuracy of 12 and 15% than that of GRNN and PNN respectively. Finally, we provided extensive numerical results to demonstrate the usage and efficiency of the proposed algorithms and complement our theoretical analysis. 相似文献
1000.
Jing Zhang Xintian Shao Jingli Yue Donghui Li Zhenhua Chen 《Nanoscale research letters》2014,9(1):639
In this work, we reported a simple, fast, and sensitive determination of ractopamine (RAC) residues in pork by using novel ractopamine-tetraphenylborate complexed nanoparticles (RT NPs) as sensors. The prepared RT NPs exhibited a fast response time of 10 s, a wide linear range from 0.1 to 1.0 × 10−7 mol/L, and a very low detection limit of 7.4 × 10−8 mol/L. The prepared sensor also presents a high selectivity for ractopamine under different pH conditions ranged from 2.85 to 7.18. These results reveal that the fabricated RT NPs can be used as efficient electrochemical sensors to determine ractopamine in animal productions. 相似文献