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排序方式: 共有1100条查询结果,搜索用时 656 毫秒
1.
Tian Xiaoying Peng Hui Luo Xuguang Nie Shiyuan Zhou Feng Peng Xiaoyan 《International Journal of Control, Automation and Systems》2020,18(4):897-910
International Journal of Control, Automation and Systems - There is a class of typical nonlinear industrial process, which can be characterized by a first-order inertia plus pure delay model in an... 相似文献
2.
几种酚类抗氧剂在润滑油中的应用 总被引:2,自引:0,他引:2
采用旋转氧弹法、高压差示扫描量热法等方法研究了5种酚类抗氧剂对6种润滑油基础油氧化安定性的改善效果。结果表明:向加氢基础油中加入0.25%(质量分数)抗氧剂2246-S和RHY510(含硫酚类抗氧剂),可使HVIWH125,HVIWH150,HVIWH500,KN4006,KN40105种润滑油基础油的诱导期由27~88min提高到226~397min;使HVIWH125,HVIWH150,HVIWH300,HVIWH500,KN4006,KN40106种润滑油基础油的起始氧化温度由193.34~198.90℃提高到205.48~230.27℃。 相似文献
3.
文章从原理上讨论了影响分米波电视发射管寿命的若干因素。并提出了若干延长寿命的建议:(1)正确的灯丝加热方法是行之有效的措施,经验证明:过分强调降低灯丝电压往往得到相反的效果。(2)必须有良好的冷却方式。(3)通过对帘栅电路的分析,说明对此电路必须作很好的处理以消除故障和防止寄生振荡。 相似文献
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Xuguang Li 《Electrochimica acta》2006,51(17):3477-3483
In this work, carbon supported PtxPd1−x (x = 0-1) nanocatalysts were investigated for formic acid oxidation. These catalysts were synthesized by a surfactant-stabilized method with 3-(N,N-dimethyldodecylammonio) propanesulfonate (SB12) as the stabilizer. They show better Pt/Pd dispersion and higher catalytic performance than the corresponding commercial catalysts. Furthermore, the electrocatalytic properties of PtxPd1−x/C were found to depend strongly on the Pt/Pd deposition sequence and on the Pt/Pd atomic ratio. At a lower potential, formic acid oxidation current on co-deposited PtxPd1−x/C catalysts increase with increasing Pd surface concentration. Nanoscale Pd/C is a promising formic acid oxidation catalyst candidate for the direct formic acid fuel cell. 相似文献
6.
Providing an easy ingress–egress (I/E) movement remains a challenge for car designers. I/E has been largely studied in kinematics, but not in dynamics. This study proposes: (1) to evaluate and describe the motor torques developed in the lower limbs and lumbar joints during I/E motions and (2) to analyse the influence of the car geometry and subject anthropometry. An experiment was performed to observe 15 subjects of three anthropometrical groups getting in and out of a car mock-up simulating three different vehicle configurations. Motor torques were extracted using an inverse dynamics analysis. Both ingress and egress motions were primarily characterised by large torques. Overall, the taller a subject and the lower the seat of the vehicle were, the larger the peak torques were. Moreover, peak torques were higher for egress than ingress. These results are discussed in regard to the current knowledge on I/E ergonomics. 相似文献
7.
压力流化床燃烧技术近二十年来在世界上得到很大发展。煤的湿法给料系统具有比干法输送系统更简单,运行调节更可靠等优点。煤水混合物可泵送的水分在25%左右,煤的粒度一般为0~6mm,表现为非牛顿的假塑性流体特性,通过级配来达到一定的稳定性和良好输送性能,且流动阻力低,不用添加剂即可实现泵送,它的应用使压力流化床的燃烧制备和输送系统成本大大降低。 相似文献
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A simple, inexpensive and one-step synthesis method of metal-containing carbon nanocapsules using an arc discharge in aqueous solution is reported. It was found that Ni, Co and Fe nanoparticles could be in situ encapsulated in carbon shells when the arc was performed respectively in aqueous solutions of NiSO4, CoSO4 and FeSO4. Transmission electron microscopy, energy dispersive X-ray spectroscopy and electron diffraction patterns of selected areas were used to determine the crystalline phase of the metal cores. To explain the formation mechanism of metal-containing carbon nanocapsules, a model of discharge in solution is proposed. This result presents a simply controllable way to synthesize metal-containing carbon nanocapsules. 相似文献
10.
Jun Yang Jianbao Li Hong Lin Xiaozhan Yang Xuguang Tong Gangfeng Guo 《Journal of Applied Electrochemistry》2006,36(8):945-950
In this paper, we describe the preparation of a porous nanosheet-stacked NiCo2O4 composite electrode using a novel electrophoretic deposition (EPD) calcination method. The effects of the deposition time and voltage, and of the calcination temperature have been investigated. The microstructure of the deposited films in the electrodes before and after calcination has also been investigated. The electrocatalytic properties of the electrodes have been investigated using cyclic voltammetry and polarization curves. The electrode films produced using this new technique have a porous structure composed of stacked hexagonal NiCo2O4 nanosheets. The resulting electrodes exhibit good electrocatalytic properties for water electrolysis. 相似文献