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71.
确定异常高压气藏地质储量和可采储量的新方法 总被引:7,自引:1,他引:6
基于文献[1]的定容,封闭,异常高压气藏的物质平衡方程式,提出了确定异常高压气藏原始地质储量,可采储量和采收率的新方法,通过实例的应用和对比表明,提供的新方法是适用的有效的。 相似文献
72.
动态聚焦技术是为了满足大屏幕高分辨率彩色显像管及高分辨率彩色显示管的发展需求而产生的一项新技术。在本文中,作者首先提出了一种动态聚焦电子枪结构,进行了数值计算与分析,制作了动态聚焦电子枪并装管实验。通过对实验样管的测试与分析。证实该枪性能良好,动态聚集效果明显。 相似文献
73.
微光CCD摄像器件综合特性的分析与比较 总被引:3,自引:1,他引:2
CCD的优良特性使其在微光电视技术领域得到了广泛运用。本文对各种微光CCD摄像器件的综合特性例如信噪比、探测率、动态范围与计数模式等进行了详细的研究与对比,并得出基本结论。 相似文献
74.
The compaction properties of an investigational drug are studied by the use of a compaction simulator. The effects of punch velocity over the range of 30-640 mm-1 on the compaction properties of the pure drug and a variety of formulas incorporating a high dose of the active compound have been investigated. The data were analyzed by applying the Heckel equation. The pure drug was found to have a high yield pressure at a relatively low punch velocity of 31 mm-1. As the punch velocity was increased there was a decrease in crushing strength, primarily as a result of increasing yield pressure. These findings indicate that the pure drug predominantly consolidated by fragmentation and elastic deformation, with a slow plastically deforming component. The information obtained on the consolidation mechanism of the pure drug and, subsequently, on model formulas were instrumental in the design and selection of a robust formula and granulation process. The advantages of conducting dosage form design and characterization studies during the early phase of tablet formulation using means such as a compaction simulator are emphasized in this investigation. 相似文献
75.
Al2O3:ZrO2 ceramics have been prepared from physically mixed pure oxide powders. The results indicate that careful processing of the
starting powders and a two-stage sintering process can avoid expensive processing methods like hot pressing/hot isostatic
pressing used for achieving high densification. The mechanical properties were measured and the resultant microstructure studied
to explain the toughening behaviour of this material. 相似文献
76.
77.
Effect of pretreatments and freezing rate on the firmness of potato tissue after a freeze–thaw cycle
Sergio Carbonell Jorge C. Oliveira & Alan L. Kelly 《International Journal of Food Science & Technology》2006,41(7):757-767
The texture of potato tissue after a freeze–thaw process using different freezing rates and different pretreatments was analysed, in order to select the best strategy for optimum preservation of the textural characteristics of pre‐frozen potato. Ten blanching conditions were tested and a two‐step blanching process with calcium chloride (0.07 g mL?1) proved the most effective in protecting the tissue after a freeze–thaw process (maximum load force around 10–55% of the raw tissue, depending on potato batch, for air‐blast freezing and 20–60% for immersion freezing). Vacuum impregnation at 100 and 400 mbar, even when followed by different pre‐drying treatments to remove excess water, was very detrimental to resistance to a freeze–thaw process (maximum load force below 10% of the raw tissue for air‐blast freezing and below 20% for immersion freezing). Microstructure analysis confirmed better tissue integrity retention with ethyleneglycol immersion freezing instead of air‐freezing. Differences were found between batches with a 6‐month difference in storage time, indicating that the fresher batch was more suitable for freezing. 相似文献
78.
79.
Equal Strain Consolidation by Vertical Drains 总被引:1,自引:0,他引:1
Chin Jian Leo 《Canadian Metallurgical Quarterly》2004,130(3):316-327
This paper shows the development of a series of closed-form solutions of equal strain consolidation in the presence of a vertical drain with smear and well resistance. Using an approach that considers the effects of both the radial and vertical drainage in a fully coupled fashion, solutions are obtained for the excess pore pressure and the degree of consolidation in the compressible soil subjected to a step- or ramp-loading situation. The closed-form solutions in the present paper may be evaluated in an electronic spreadsheet on a standard personal computer. 相似文献
80.