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91.
精确界定油井温度界限值,对回油温度进行自动控制是降低气耗、能耗的有效措施。首先推导了单井温度界限数值模型,然后针对朝阳沟油田的实际情况对油井进行了分类,并选择了有代表性的单(环)井进行了试验。通过现场实测值与利用模型计算的预测值比对,符合率达到了70%以上。在此基础上利用温度界限分析仪进行了进一步的验证试验,结果符合预期。在单(环)井上加装了掺水量自动控制装置,实现了回油温度的自动控制。 相似文献
92.
93.
Experimentally determined p,V,T data are reported for toluene, trichloromethane, dichloromethane, acetonitrile, aniline, and n-dodecane at 278, 288, 298, 313, and 323 K, except for dichloromethane, for which the highest temperature was 298 K. At each temperature, measurements were done at pressures up to about 280 MPa or (for aniline and n-dodecane) at a lower pressure slightly below the freezing pressure at the temperature of measurement. Values of the isobaric expansivity isothermal compressibility and (for toluene, trichloromethane, dichloromethane, and acetonitrile) internal pressure, derived from the p,V,T data, are presented. 相似文献
94.
High speedsteel (HSS) ,ischaracterizedbyex cellenthardness ,wearresistance ,and goodredhardness .Recently ,HSSisappliedtomanufacturehotrollingrollstoproducestripsofgoodshapeandsmallcrownwithextendedrollservicelife[1,2 ] .TheHSSisappliedtomanufacturerollcollarfor… 相似文献
95.
96.
高密度澄清池在邯钢第二污水处理厂的应用 总被引:1,自引:0,他引:1
高密度澄清池是一种新型高效的澄清池。介绍了高密度澄清池的工艺原理、运行条件和主要参数及在邯钢第二污水处理厂的应用情况。 相似文献
97.
高边坡深孔预裂爆破是一项对施工质量、安全要求极高的爆破技术, 必须进行科学的爆破技术设计,确定合理的爆破参数;高度重视爆破钻孔工艺、装药工艺、网络工艺以及边坡稳定性地质分析.在洞巴水电站中不允许采用超欠平衡的开挖方法进行施工,利用设计台阶高度,采用深孔预裂爆破对溢洪道高边坡的稳定及开挖平整度进行有效控制,取得良好效果. 相似文献
98.
本文从温度、酸度对大曲酒产、质量的影响,揭示大曲酒夏季"掉排"的主要原因为高温、高酸环境抑制了酿酒酵母的发酵,降低了酿酒酵母的发酵力,从而影响了大曲酒的产、质量。 相似文献
99.
Aboubakar Sako Kenneth G. MacLeod Catherine M. O’Reilly 《Journal of Great Lakes research》2007,33(4):806-815
In this study, we measured growth trends in oxygen and carbon isotopic ratios in whole sagittal otoliths from three adult centropomid fish (Lates stappersii) from each of three sub-basins of Lake Tanganyika, East Africa. Sampling density was 20 to 50 samples per otolith. Both δ18O and δ13C values increase with age. The δ18O data suggest that otoliths were precipitated near the expected equilibrium with the ambient environment (ca. +3.5‰) and support a migration pattern from surface waters during larval stages to deeper waters (40 to 80 m) for mature fish. Relatively high δ18O values in the southern sub-basin are consistent with cooler temperatures in the region during seasonal upwelling. The δ13C increase from otolith core to edge is large (up to 4‰) and is interpreted as due to ontogenetic changes in diet and contributions from a decrease in the proportion of respired CO2 incorporated into otolith carbonate as metabolic rates of the fish dropped with maturity. The data seem to successfully reveal life strategy and migration patterns of L. stappersii, document regional differences in lake conditions, and provide a record of temperature within the water column during which the fish lived. Higher resolution studies and analyses of historical samples could be used to constrain modern and past growth patterns, and to reconstruct past temperature gradients and productivity patterns in the lake. 相似文献
100.
Shunsuke Ohashi 《Electrical Engineering in Japan》2005,150(1):71-77
Magnetic bearing using pinning force of a permanent magnet and a high‐temperature superconductor has been developed. Additional permanent magnet is introduced to increase the levitation force of the magnetic bearing. In this hybrid magnetic bearing system, levitation force is mainly given by the repulsive force of the permanent magnets, and stability for the lateral direction is given by pinning force of the superconductor. The experimental device is developed. A ring‐type superconductor and a bulk one are examined. Levitation characteristics of the hybrid magnetic bearing are measured. The bulk superconductor shows better characteristics of both levitation and lateral stability than the ring one. Levitation force of the hybrid system becomes about twice as large as that of the nonhybrid one. Although, the repulsive force of the permanent magnet decreases the lateral stability of the system, its influence becomes small by choosing an adequate position of the permanent magnets and the superconductor. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(1): 71–77, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10350 相似文献