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61.
预焙铝电解槽阳极钢爪自焙保护环优化技术 总被引:1,自引:0,他引:1
就目前预焙铝电解槽所用的自焙保护环的制作进行了研究.提出了优化方案,通过工业试验认为.自焙保护环的制作技术优化后.可以给企业创造显著的经济效益。 相似文献
62.
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64.
消能锥形阀是一种用于中、高水头下的消能控流阀门,其内部结构设计的好坏直接影响着控流效果。为探究消能锥形阀在不同开度下,过流流量及内部流场的变化情况。进行了模型试验与CFD数值模拟计算,试验中发现开度从100%关至85%时出现了流量反而上升、进口压力下降的情况。利用CFD数值模拟的方法对内部流场进行了可视化研究。研究结果表明,在全开状态下锥形阀内部存在以下问题:过强的局部高速高压区域、低速流动死区范围过大、涡流区过度影响高速过流部分。并对锥形阀进行了一定的结构改进,优化了其内部流场情况。 相似文献
65.
Pd catalysts supported on TiO2, ZrO2, ZSM-5, MCM-41 and activated carbon were used in catalytic wet oxidation of hydrocarbons such as phenol, m-cresol and m-xylene.
It was found that the Pd/TiO2 catalyst was highly effective in the wet oxidation of hydrocarbon. The activities of catalysts with various hydrocarbon species,
catalyst support, oxidation state of catalyst performed in a 3-phase slurry reactor show that reaction on Pd surface is more
favorable than that in aqueous phase and that the active site is oxidized Pd in catalytic wet air oxidation of hydrocarbons.
Based on the experimental results, a plausible reaction mechanism of wet oxidation of hydrocarbons catalyzed over Pd/TiO2 catalyst was proposed. This catalyst is superior to other oxide catalysts because it suppressed the formation of hardly-degradable
organic intermediates and polymer. 相似文献
66.
Kazuyuki Tsubone Noriko Uchida Kunio Mimura 《Journal of the American Oil Chemists' Society》1990,67(7):451-454
A series of new amphoteric surfactants having a phosphoric acid group, a tertiary amino group and a 2-hydroxyalkyl group, sodium 2-(N-2-hydroxyalkyl-N-methyl-amino)ethyl hydrogen phosphates (alkyl: n-tetradecyl, n-hexadecyl, n-octadecyl), were prepared by an addition reaction of 1,2-epoxyalkanes to N-methylaminoethanol, followed by the introduction of a phosphoric acid group and neutralization with sodium hydroxide. The structures of these compounds were confirmed by spectroscopy and elemental analysis. The solubility in solvents, Krafft point, surface tension, critical micelle concentration (CMC), occupation area of the molecule at the surface of aqueous solutions and foaming power were measured. It was shown that a 2-hydroxyethyl group in a long alkyl chain seemed to behave as a hydrophobic part. 相似文献
67.
冷却塔的冷却效果主要由淋水填料的冷却数和冷却塔的有效高度决定,淋水填料的换热性能决定了冷却塔的主要换热效果。为提高抗震冷却塔的抗震效果,淋水填料采用金属填料。通过在某工程中抗震冷却塔金属填料与普通塑料填料应用的对比分析,研究金属填料的特点及适用性,为抗震冷却塔的设计提供依据。 相似文献
68.
This work investigates the electric field effect on nitrogen oxide (NO) pollutant formation and emission composition of premixed flames in order to provide better insight on the mechanism of controlling the combustion process by electro-physical means. The present study aims to investigate experimentally the effect of radial DC electric field on premixed laminar methane flame. The electric field effect on flame shape, emission composition and NO emission index of flame is investigated experimentally under the action of direct-current electric field under varying equivalence ratio and level of oxygen enrichment. The results show that ionic wind effects cause the distortion in flame shape. The ionic wind effects diminish with increasing flow rate and level of oxygen enrichment. Minimal effects on NO are measured for flames under the influence of electric field and vanished as the level of oxygen enrichment is increased. This was well supported by the temperature profile measurement in the post flame gas showing no field-induced modification also. It seemed that the action of an electric field on a flame with a geometry that remains practically undeformed produces very minimal effect on pollutant emission. 相似文献
69.
玉米浆为有机氮源的L-乳酸发酵的研究 总被引:5,自引:0,他引:5
利用细菌厌氧发酵生产L-乳酸,以降低L-乳酸生产成本为主要目的,实验以玉米浆为有机氮源,以硫酸铵为主要无机氮源,研究了不同接种量对发酵过程的影响;并就以玉米浆替代酵母粉、豆粕水解液、生物素为有机氮源的L-乳酸发酵进行了对比研究实验,实验证明了玉米浆做为有机氮源用于L-乳酸发酵的可行性。在保证生产能力的同时,使用玉米浆为有机氮源对进一步降低L-乳酸生产成本,减少玉米浆对环境的污染进行了探索。 相似文献
70.
《Robotics and Autonomous Systems》2014,62(4):422-435
In recent years, autonomous robots have increasingly been deployed in unknown environments and required to manipulate or categorize unknown objects. In order to cope with these unfamiliar situations, improvements must be made both in sensing technologies and in the capability to autonomously train perception models. In this paper, we explore this problem in the context of tactile surface identification and categorization. Using a highly-discriminant tactile probe based upon large bandwidth, triple axis accelerometer that is sensitive to surface texture and material properties, we demonstrate that unsupervised learning for surface identification with this tactile probe is feasible. To this end, we derived a Bayesian nonparametric approach based on Pitman–Yor processes to model power-law distributions, an extension of our previous work using Dirichlet processes Dallaire et al. (2011). When tested against a large collection of surfaces and without providing the actual number of surfaces, the tactile probe combined with our proposed approach demonstrated near-perfect recognition in many cases and achieved perfect recognition given the right conditions. We consider that our combined improvements demonstrate the feasibility of effective autonomous tactile perception systems. 相似文献