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991.
国外几种脱硫醇工艺技术 总被引:1,自引:0,他引:1
硫醇是一种易挥发、有毒、腐蚀活性强的物质,在环保要求越来越严格的今天,必须将原油和凝析气中的硫醇加以脱除,才能达到环保要求。文章介绍了目前世界上采用的几种脱硫醇工艺。 相似文献
992.
993.
多序列迭加生成值的合理性判定——病态信息检测案例 总被引:2,自引:0,他引:2
论文针对目前普遍存在于各种管理性考评工作中的专家打分问题进行了研究,提出了一种特定条件下专家打分值的合理性判定模型。该方法已在某组织的实际考评工作中进行了实验与应用,取得了较好的效果,为控制专家打分随意性和病态信息的产生,提供了一种新的思路。 相似文献
994.
针对钓鱼攻击的防范技术研究 总被引:1,自引:0,他引:1
论文从网络攻击的角度,提炼出了三种钓鱼攻击的模型,并对其实现机理、关键技术进行了比较详细的剖析。然后,针对钓鱼攻击本身的特点,提出了一种同时具备双因素认证和双向认证优点的认证模型来防御钓鱼攻击。 相似文献
995.
昆2井优快钻井及油气层保护技术 总被引:1,自引:0,他引:1
昆2井是一口位于柴北缘西段的昆特依凹陷潜伏Ⅰ号圈闭上的风险探井,设计井深为5950m。针对柴北缘深探井存在的主要技术难题,制定了昆2井的技术对策。通过对钻井设备的优选、井身结构的优化、钻头及钻具组合的优选、钻井参数及钻井液性能的优化、油气层保护技术的研究与应用,形成了一套适合于柴北缘的优快钻井技术,使昆2井的完钻井深达到5950m。与邻区的深探井平均水平相比,在井深增加888m、大尺寸井眼段更长的前提下,昆2井的钻井、完井周期分别缩短了98.75d、124.2d,钻机月速度增加了317m/台,平均机械钻速增加了0.82m/h。根据“理想充填新理论”,确定了保护油气层的最优复配暂堵方案,利用该方案所配制的钻井液其渗透率恢复值达到了87.5%以上,流变性能良好,滤失量低,对改善泥饼质量、增强井壁稳定性有明显的效果。 相似文献
996.
The simultaneous contrast effect is investigated in this article. A total of 174 and 154 test/induction combinations were studied for CRT and surface colours respectively. Each combination was assessed by nine observers using a matching technique. The test and induction colours used for CRT colours were similar to surface colours using fabric samples. The results indicated a strong lightness contrast effect for both CRT and surface media; that is, the lightness of a test colour surrounded by a lighter induction colour was reduced for both CRT and surface colours. However, the effect in CRT medium was more pronounced than in the surface medium. © 2004 Wiley Periodicals, Inc. Col Res Appl, 30, 13–20, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20074 相似文献
997.
Optimum thermoeconomic and thermodynamic performance characteristics of an irreversible three-heat-source heat pump 总被引:1,自引:0,他引:1
The coefficient of performance and specific heating load of an irreversible three-heat-source heat pump are given by using a general cycle model affected by the finite-rate heat transfer, heat leak and internal irreversibility of the cyclic working fluid. The heat pumping load divided by the total cost per unit time is taken as a new objective function and used to investigate the performance of the heat pump. The thermoeconomic and thermodynamic performance characteristics of the heat pump are discussed in detail. Some important performance parameters such as the thermoeconomic objective function and coefficient of performance are optimized. The optimally operating regions of the heat pump and the bounds of several performance parameters are determined. Finally, it is pointed out that the Carnot heat pump may be taken as a special case of a three-heat-source heat pump and consequently its optimal performance can be directly derived from the results obtained here. 相似文献
998.
Li-Tang Yan 《Polymer》2006,47(18):6472-6480
The surface-directed spinodal decomposition (SDSD) of polymer binary mixture with different values of surface potential is numerically simulated in three-dimension (3D) by cell dynamic systems (CDS). Furthermore, the growth laws of the wetting layer are theoretically analyzed by the current equation and the dynamical scaling. The results show that the thickness of the wetting layer increases with the increasing surface potential. The crossover, which is later for larger values of surface potential, appears in the evolution curve of the wetting layer. Before the crossover, the growth law is the surface potential dependant growth law. Subsequently, the growth law is the typical Lifshitz-Slyozov (LS) growth law. The results indicate that the surface potential can result in the mutual transformation between completely wetting and partially wetting for the substrate interface. It can be found that the higher surface potential leads to the faster and stronger transmission of the effect of the substrate on the spinodal decomposition in the bulk. 相似文献
999.
1000.
The growth of Li1+xMn2O4 via detonation reaction was investigated with respect to the presence of an energetic precursor, such as the metallic nitrate and the degree of confinement of the explosive charge. The detonation products were characterized by scanning electron microscopy. Powder X-ray diffraction and transmission electron microscopy were used to characterize the products. Li1+xMn2O4 with 1-2 μm spherical morphology and more uniform secondary particles, but with smaller primary particles of diameters from 20 to 60 nm and a variety of morphologies were found. The oxides produced by this cheap method affirmed the validity of detonation synthesis of nano-size powders. 相似文献