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31.
氧化焰烧成铜红釉   总被引:1,自引:0,他引:1  
本研究以SiC作还原剂,采用氧化焰烧成,试制成功了在1250~1260℃下烧成的铜红釉,克服了传统的还原焙烧成方法的不足,简化了生产工艺,提高了铜红釉的成品率。  相似文献   
32.
研究了在冰醋酸-盐酸介质中,以NaI作还原剂,Fe3+作催化剂,测定二叔丁基过氧化物的条件,建立了在100℃条件下催化碘量法测定二叔丁基过氧化物的新方法。该法用于聚丙烯塑料中微量过氧化物的测定,准确、可靠、方便。回收率为98.7%,相对标准偏差为0.64%。  相似文献   
33.
针对无先验地图条件下电力管廊无人机自主巡检能力不足的问题,本文提出了一种不依赖先验地图的无人机巡检方法。首先,无人机搭载激光雷达,通过SLAM(Simultaneous Localization and Mapping)算法进行实时场景构图,并基于RRT(Rapidly-exploring Random Tree)算法对构建的全局栅格地图进行边界搜索;其次,针对传统RRT算法难以判断环境地图完整性、保障巡检全面性的问题,提出了一种基于数字图像处理的边界检测方法。通过Canny算子对实时构建的地图进行边缘检测,并对地图进行完整性评估。最后,为验证本文提出方法的有效性,在江苏无锡处某220kV电力管廊的仿真模型中进行验证,分别采用RRT算法和本文改进算法进行自主巡检测试,结果表明本文提出的算法相比RRT算法可提升21.8%的巡检覆盖率。  相似文献   
34.
By analyzing the extended X-ray absorption fine structure (EXAFS) of the Mo K-absorption edge, structural information for both oxidic and sulfided K-MoO3/-Al2O3 catalysts with different potassium content was obtained. The oxidic samples show two backscatterer peaks in the radial distribution function (RDF), which correspond to the Mo-O coordinations in the nearest Mo-O shell. The nearest oxygen atoms are present with large configurational disorder. The RDF for the K/Mo = 0 sample is significantly different from that for crystalline MoO3 and ammonium heptamolybdate. The RDFs for potassium promoted samples are, in some extent, similar to that for ammonium heptamolybdate. The sample with K/Mo = 0.8 and that with K/Mo=1.5 do not show obvious difference in their local Mo-O structures. The EXAFS results support the earlier conclusions from Raman spectroscopy studies on identical samples [7]. When the samples are sulfided, a rearrangement of the local neighbors around Mo atoms takes place, to form small MoS2-like crystallites. The Mo-S and Mo-Mo coordination distances on these catalysts are the same as those in crystalline MoS2, but the coordination numbers are significantly lower than in MoS2. The EXAFS results indicate that Mo species on the K/Mo=0 catalyst mainly consist of Mo-S-Mo units (the basic building units of MoS2), which are highly dispersed and show a higher level of disorder than in MoS2. With the modification by the potassium promoter, Mo species are significantly aggregated and their local neighbors are more similar to those in MoS2, but the Mo species still exist in a state of high dispersion.  相似文献   
35.
Video frame-rate up-conversion is one of the common operations for tampering digital videos in the temporal domain, such as creating fake high-quality videos and splicing two video clips with different frame rates. However, few existing works have been proposed for detecting this form of tampering operation. Based on the analysis of extensive experiments, we found that frame-rate up-conversion algorithms employed in most current video editing softwares will inevitably introduce some periodic artifacts into inter-frame similarity in the resulting video frame sequence. By analyzing such artifacts, we propose a simple yet very effective method to expose video after frame-rate up-conversion, and further estimate its original frame rate. The experimental results evaluated on 100 original videos at different frame rates have shown the effectiveness of the proposed method. The average detection accuracy can achieve as high as 99 % on noise-free videos in uncompressed and H.264/AVC formats. Besides, the proposed method is robust to noise as the detection accuracy could reach over 85 % and 95 % on noised videos with Gaussian white noise when SNR is 33 db and 36 db respectively.  相似文献   
36.
本文介绍了改性聚丙烯(PP)基泡沫材料用的水溶性胶粘剂的研制。该胶粘剂不影响泡沫材料的阻燃性能和吸声性能,并有较好的热稳定性和储存性以及优化的耐水性。  相似文献   
37.
球磨效率探讨   总被引:2,自引:0,他引:2  
主要讨论了球石的装载量、球石空隙率、球石级配、泥浆密度等因素对球磨效率的影响。运用正交试验优选了各因素。  相似文献   
38.
卞惠芳 《贵州化工》2004,29(6):29-30
该文利用正交法设计实验,以聚合硅酸硫酸铝为混凝剂对印染废水进行了混凝处理研究。研究结果表明,聚合硅酸铝处理印染废水效果较好,其最佳组合方式为:温度40℃,pH值为6,聚合硅酸硫酸铝的投加量为860mg/L,搅拌时间控制为15min。在最优化条件下,COD的除去率为75.0%,获得了较好的效果。  相似文献   
39.
The melt intercalation method was employed to prepare poly(butylene terephthalate) (PBT)/montmorillonite (MMT) nanocomposites, and the microstructures were characterized with X‐ray diffraction and transmission electron microscopy. Then, the nonisothermal crystallization behavior of the nanocomposites was studied with differential scanning calorimetry (DSC). The DSC results showed that the exothermic peaks for the nanocomposites distinctly shifted to lower temperatures at various cooling rates in comparison with that for pure PBT, and with increasing MMT content, the peak crystallization temperature of the PBT/MMT hybrids declined gradually. The nonisothermal crystallization kinetics were analyzed by the Avrami, Jeziorny, Ozawa, and Mo methods on the basis of the DSC data. The results revealed that very small amounts of clay (1 wt %) could accelerate the crystallization process, whereas higher clay loadings reduced the rate of crystallization. In addition, the activation energy for the transport of the macromolecular segments to the growing surface was determined by the Kissinger method. The results clearly indicated that the hybrids with small amounts of clay presented lower activation energy than PBT, whereas those with higher clay loadings showed higher activation energy. The MMT content and the crystallization conditions as well as the nature of the matrix itself affected the crystallization behavior of the hybrids. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3257–3265, 2006  相似文献   
40.
基于全路径的研究现正处于起步阶段,提出了一种全新的NRPS算法(不重复路径搜索算法)和AR规则来对程序的源文件进行静态分析,生成有向无负权图,进而得到不重复路径集;并结合粒子群优化算法最终生成最优测试用例。实验表明,该方法具有可行性。  相似文献   
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