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81.
介绍了一种新型双族流平焰烧嘴的设计思路、结构参数及工业试验结果。其结构特点是每个部件都易装易卸,其煤气旋流器的位置可根据煤气压力变化进行调节,无需稳焰器就可保证煤气压力在较大范围波动时,都可形成稳定的平展火焰。 相似文献
82.
It is demonstrated that glassy carbon powder can be thermochemically activated. During activation, a film with open pores is created on the glassy carbon particles. This film has a large internal surface area, which is accessible to liquids and gases. A simple model for the evolution of the internal surface area in glassy carbon powder during thermochemical gas-phase oxidation is also presented and compared with experimental data. Experimental results are in qualitative agreement with the model. We found that a sharp particle size distribution is desirable with regard to potential technical applications. 相似文献
83.
84.
The results of the measurements of the concentrations of freons (F-11 and F-113), chloroform (CHCl3), trichloroethane (CH3CCl3) and carbon tetrachloride (CCl4) in air are presented. The data concern concentration measurements that have been conducted in Krakow since half way through 1997 to the end of 1999. The mean monthly values of these concentrations have been compared with the data from Mace Head, the station situated at a similar longitude as Krakow. It has been concluded that, in the observed period of time, the concentrations of the pollutants in Krakow are higher than in Mace Head. The mean monthly concentrations of F-11 and CCl4 decrease in Krakow faster than in Mace Head (2.5 and 3.3 times, respectively). The concentrations of CHCl3 and CH3CCl3 decrease at both locations, but the change is greater in Krakow. In Krakow, the observed increase of F-113 is 0.13 ppt/month and has an opposite trend than in the same period at Mace Head. 相似文献
85.
塔里木盆地塔中沙漠区高分辨率地震勘探效果 总被引:1,自引:0,他引:1
塔中沙漠区地表被北东—南西向条带状沙层所覆盖,地形起伏剧烈,松散沙层厚度变化巨大,给地震资料采集、处理、解释带来了很大的困难。通过联合攻关,从地震波激发能量下传和反射波接收的研究入手,实现了全部潜水面以下激发,因地制宜、避高就低埋置检波器优化观测系统;针对该区石炭系和志留系低幅度构造、薄储层圈闭难以落实,奥陶系内幕地震资料反射波能量弱、信噪比低、叠加成像困难等问题,开展了沙丘对地震波吸收衰减分析和补偿技术、地表一致性处理技术、多域迭代静校正技术、精细速度场模型确立和偏移成像等配套技术的研究开发与应用。从而极大地改善了塔中沙漠区地震资料的品质,使中深层的石炭系、志留系、奥陶系对应的地震剖面主频从18~20Hz提高到36~40Hz;形成了塔中沙漠区油气勘探技术系列,精细刻画了塔中Ⅰ号带,锁定了油气勘探目标,推动了台盆区油气勘探再掀新高潮。 相似文献
86.
Amjad B. Soulaka William R. Morrison 《Journal of the science of food and agriculture》1985,36(8):709-718
Starches isolated from 23 bread wheats (Triticum aestivum) and 26 durum wheats (T. durum) contained 26.3-30.6% (mean 29.1%) total amylose, 19.3–25.1% (mean 22.9%) apparent amylose and 783–1144mg 100g?1 (mean 977 mg 100g?1) lysophos-pholipids. Gelatinisation temperatures were 57.3–64.9°C (mean 61.8°C) and enthalpies 6.4–11.8 Jg?1 (mean 9.7Jg?1) in excess water, measured by differential scanning calorimetry. There were no correlations between any of these parameters. Starch granule size distributions were determined with a Coulter Counter and 100–channel analyser. A-granule mean volumes were 1235–2585μm3 (av. 1778), modal volumes 863–1804μm3 (av. 1264), mean diameters 13.9–16.0μm (av. 13.99), and specific surface areas 0.236–0.302m2g?1. B-granule mean volumes were 35.4–100.4μm3 (av. 55.9), modal volumes 16.5–54.5μm3 (av. 27.7), mean diameters 3.66–5.07μm (av. 4.09), and specific surface areas 0.684–0.920m2g?1. The B-granule contents of the starches were 12.8–34.6% (av. 27.3) by weight (sedimentation method) and 13.0–37.3% (av. 24.0) by volume (Coulter method), the latter being the more accurate method. 相似文献
87.
鄂尔多斯西缘前陆盆地巨厚黄土地区地震采集技术 总被引:2,自引:2,他引:0
鄂尔多斯西缘前陆盆地表层地质地貌极其复杂,有巨厚黄土区、黄土-沙漠区及山前砾石-黄土区,独特的黄土地貌使得地震采集面临着诸多技术难题。根据以往巨厚黄土地区地震采集经验,采用多种方法系统地开展黄土表层结构精细调查,深入研究黄土地球物理特征及激发因素与表层黄土结构之间的关系,优选激发井位和井深,确保了激发效果;采用小道距、三线小线距、高密度空间采样技术,获得了高信噪比、高分辨率地震资料。研究表明,巨厚黄土地区地震采集时应优选激发井位和岩性,合理选择激发井深;坚持多深井组合激发、单井药量不宜过大总药量要大两项基本原则;采用高密度采样技术,提高采集资料的覆盖次数和信噪比。图10表1参15 相似文献
89.
XU Shun dou 《中国邮电高校学报(英文版)》2002,9(2)
1 IntroductionInordertoimprovethequalityofpostalserviceandtakeadvantageofautomatedmailsortingequip ments,ithasbeendeterminedtoconstructthepostalareacenterofficesysteminChinaPostalSer vice (CPS) .ThecruxoftheproblemfacedbyCPSistoredesignthepostalcommunica… 相似文献
90.
MODELING LIQUID MASS TRANSFER IN HIGEE SEPARATION PROCESS 总被引:1,自引:0,他引:1
Correspondence concerning this paper should be addressed to Professor Richard S.H. Mah. Hsien-Hsin Tung is now affiliated with Department of Chemical Engineering, California Institute of Technology
Penetration theory is used to describe the liquid mass transfer in Higee separation process. Within a possible range of effective areas, it is shown that the predicted mass transfer coefficients are in reasonable agreement with the estimated mass transfer coefficients. The estimated coefficients were calculated from the experimental data and the possible effective areas. Hence it is concluded the penetration theory is generally applicable to describe liquid mass transfer in Higee separation process. The comparison also suggests that liquid mixing at the junctions of packing materials may be more complete in Higee process than in traditional process. 相似文献
Penetration theory is used to describe the liquid mass transfer in Higee separation process. Within a possible range of effective areas, it is shown that the predicted mass transfer coefficients are in reasonable agreement with the estimated mass transfer coefficients. The estimated coefficients were calculated from the experimental data and the possible effective areas. Hence it is concluded the penetration theory is generally applicable to describe liquid mass transfer in Higee separation process. The comparison also suggests that liquid mixing at the junctions of packing materials may be more complete in Higee process than in traditional process. 相似文献