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61.
液化流程中氧液化器的流程组织和相关参数确定 总被引:1,自引:2,他引:1
简介了中压循环液化和低压循环液化两种主要的液化流程,对两种流程进行了比较;分析了在中压循环液化流程中单独设置氧液化器的必要性;探讨了在低压氧液化和中压氧液化时不同的氧液化器流程组织形式;提出了低压氧液化时合理的流程组织方案和相关参数。 相似文献
62.
介绍了国内某玻璃厂浮法玻璃熔窑使用氧气助燃的一次尝试,简介了其中底烧法的使用方法、过程和效果,列举了有待改进的内容。 相似文献
63.
In this paper, dimensional analysis has been carried out to derive general equations that predict: the total gas transferred to the ambient reservoir water from an air bubbler, total volume entrained, and total energy consumed for a known or equivalent linear stratification. The equations are tested by comparison with a one-dimensional bubbler model developed by the authors. It is shown that the oxygen transfer to the water column can be significant if small bubbles are used. The mechanical destratification efficiency ηmech (%), destratification time per unit surface area Γ?(s/m2), oxygen dissolution efficiency Ω (%), and oxygen transferred per unit input energy are examined as functions of bubble size. It is concluded that an average bubble radius of 1?mm should be considered for design purposes. However, if oxygen transfer from the bubbler is not considered important, then a bubble size of up to 4?mm is acceptable for destratification purposes. 相似文献
64.
G105钻杆腐蚀失效分析 总被引:2,自引:3,他引:2
采用金相分析并结合X射线衍射、扫描电镜和电子探针能谱分析等方法,分析了某油田G105钻杆的腐蚀失效原因。结果表明,因腐蚀产物脱落造成井下堵水眼事故,而钻杆停钻后因未及时清理泥浆而造成钻杆内表面附着泥浆,含有氯离子的泥浆加速了其对钻杆的氧腐蚀。就停钻腐蚀问题提出了预防措施。 相似文献
65.
Low dielectric constant (low k) carbon-doped silicon oxide (CDO) films are obtained by plasma-enhanced chemical vapor deposition. The k value of the as-deposited CDO film is less than 2.9. However, the k value may be changed during the integration process. In integration process, photoresist removal is commonly implemented with oxygen plasma ashing or by wet chemical stripping. In this work, the impact of oxygen plasma treatment has been investigated on the quality of the low-k CDO films. Different plasma treatment conditions, including variable pressure, r.f. power, and treatment time were employed. A variety of techniques, including X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy, time-of-flight secondary ion mass spectrometry (TOF-SIMS), atomic force microscopy (AFM), and scanning electron microscope (SEM) were used to analyze the effect of the oxygen plasma post-treatment on the low-k CDO films. The result indicates that oxygen plasma will damage the CDO film by removing the entire carbon content in the upper part of the film with increasing treatment time, which results in an increase in the k value and film thickness loss. Our result also confirms that with low r.f. power and low pressure, the damage will be less. 相似文献
66.
67.
Low temperature silicon direct bonding for application in micromechanics: bonding energies for different combinations of oxides 总被引:3,自引:0,他引:3
Gertrud Kräuter Andreas Schumacher Ulrich Gösele 《Sensors and actuators. A, Physical》1998,70(3):100-275
Plain or structured hydrophillic silicon wafers covered with native oxide or with thermally grown oxide layers have been directly bonded at room temperature; afterwards, the samples were annealed at 100°C to 400°C. There is a significant difference in the observed bonding energy depending on the wafer pairing chosen. If one or both wafers are covered with a native oxide layer, high bonding strengths are reached even at low temperatures. This can be explained by the different diffusion behaviour of water molecules through a thick thermal oxide layer on one hand, and through a thin native oxide layer on the other hand. Two different methods for the activation of the wafer surfaces just prior to bonding are described. 相似文献
68.
Field measurements were conducted to investigate the onset and growth of hypoxia in the Tone River Estuary. Vertical profiles of dissolved oxygen (DO), salinity, and temperature were measured along the deepest line of the estuary. Rates of oxygen consumption by water and sediment in a salt wedge were obtained using laboratory tests. The measurements showed that hypoxia frequently occurred in the front part of the salt wedge and expanded its area toward the river mouth during the summer when the river flow rate was small. The data also suggested that the onset of hypoxia was delayed by the estuarine circulation which supplied oxygen-rich seawater to the salt wedge. To simulate this phenomenon, a two-dimensional flow model in the vertical-longitudinal plane was constructed by transversely integrating the k–ε model equations. The results of model simulation for three months in the summer of 1997 closely matched the field data. The model simulation proved that DO degradation is highly correlated with the residence time of salt water in the estuary. 相似文献
69.
70.
Three dimensionally ordered macroporous(3 DOM) Ce-based catalysts were successfully prepared via a surfactant-assisted colloidal crystal template(CCT) route. The as-synthesized catalysts showed wellordered structures with macropores and small interconnected pore windows. The Raman results indicate that the catalyst persists pure fluorite cubic phases until the molar ratio of Mn exceeds 0.3, therefore MnO_x particles form and impede the contact of the active site and the reagent and restraining soot combustion. The doping of Nd into MnO_x-CeO_2 enhances the catalytic activity because of increased oxygen vacancy, Mn~(4+)content and stronger redox ability. Nd-doping also improves thermal stability of the catalyst due to less sintering and none phase separation after thermal aging. The fresh and aged Mn_(0.3)Ce_(0.6)Nd_(0.1)O_2 catalysts show the maximum oxidation rate for soot at 331 and 355 ℃ in the O_2/N_2 atmosphere, achieving a nearly 100% CO_2 selectivity. 相似文献