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91.
By synthesizing reactive powders via a self-sustaining combustion synthesis, the glycine-nitrate process, the gadolinium-doped celia (GDC) with the chemical formula Ce0.8Gd0.2O1.9 was prepared. The resultant powders were dispersed with the terpineol as the dispersant through different methods such as ball milling and high-shear dispersing. Coagulation factor (CF) was used to mark the degree of agglomeration on the nano-scale GDC in this work. The effect of agglomeration on the densification behavior at different sintering temperatures was investigated. The studies indicated that agglomeration retarded the densification at the sintering stage. The powders with better dispersion exhibited a higher sintered density at the same temperature. After effective dispersion treatment, GDC could be fully densified at the sintering temperature of 1300 ℃. The densification temperature was significantly lower than those reported previously. The high sintering kinetics of the ceramics was obtained based on the agglomeration control. 相似文献
92.
提出由顾客的质量感知、服务接触的构成要素、服务接触属性构成的服务接触单元概念,以模糊集合对其进行数量化表示,用模糊统计方法测评其总体评价值.提出基于模糊贴近度的指数平滑估算方法,应用逐项贴近度最大的原则对历史数据进行排列,从而只需积累一定数量的分指标和总体评价值就可从被测服务接触单元的分指标值估计总体评价值. 相似文献
93.
西霞院水电站是小浪底水利枢纽的反调节配套工程,厂用电源的引接方式要满足重要厂用负荷的安全、可靠运行,特别是重要防汛电源的可靠运行,同时也要考虑设备布置方便。文中介绍一个相对完善的厂用电源引接方式方案,并对其技术性能加以分析。 相似文献
94.
采用有限元方法建立了二维平面水流模型,并引入驻点的概念模拟水中桩柱对水流的影响,即在计算中将网格节点设置于桩柱处,并在该节点设置滞流边界条件,即流速为0m/s.以长寿朱家坝码头的高桩码头方案为算例进行了模拟计算,结果表明该方法可以较好地模拟桩群对水流流速、流态的影响. 相似文献
95.
96.
Lifu Zhang Mingyue Zhang Lizhe Wang Yi Cen 《International journal of remote sensing》2013,34(20):6646-6656
ABSTRACTHyperspectral remote sensing plays an important role in a wide variety of fields. However, its specific application for land surface analysis has been constrained due to the different shapes of thick, opaque cloud cover. The reconstruction of missing information obscured by clouds in remote-sensing images is an area of active research. However, most of the available cloud-removal methods are not suitable for hyperspectral images, because they lose the spectral information which is very important for hyperspectral analysis. In this article, we developed a new spectral resolution enhancement method for cloud removal (SREM-CR) from hyperspectral images, with the help of an auxiliary cloud-free multispectral image acquired at different times. In the fixed hyperspectral image, spectra of the cloud cover pixels are reconstructed depending on the relationship between the original hyperspectral and multispectral images. The final resulting image has the same spectral resolution as the original hyperspectral image but without clouds. This approach was tested on two experiments, in which the results were compared by visual interpretation and statistical indices. Our method demonstrated good performance. 相似文献
97.
钙基吸收剂脱硫反应特性的研究 总被引:5,自引:0,他引:5
本文对两种钙基吸收剂-CaO和Ca(OH)2的脱硫反应机理进行了试验研究。对两者的反应活性进行了比较,并就一些因素对脱硫活性和影响作了研究,所得结论对脱硫反应的优化,脱硫剂的选择及干法FGD装置的开发和研制有参考意义。 相似文献
98.
Quasi-brittle solids usually contain many cracks. When numerical methods are used, it is difficult to simulate all the cracks’ behaviors, especially when the crack propagation is included. To surmount the difficulty, a new procedure combining the subdomain boundary element method and the generalized self-consistent scheme is presented. The behavior of a single crack is analyzed first. The obtained information is then used to predict the overall behavior of the cracked solids. The relationship between the overall response of the cracked solids and the growth of wing cracks is established numerically. A cohesive-crack model is used to simulate the fracture process zone of the quasi-brittle solids. Besides, the advancement of the wing crack tip is used as a control variable. An incremental iteration algorithm is developed to trace the growth of the wing (secondary) cracks, which is not known a priori. The influence of the crack angle and the friction coefficient on the effective moduli is also investigated. Finally, a gypsum square plate containing orderly distributed cracks is analyzed to illustrate the adequacy and efficiency of the present procedure. 相似文献
99.
研究了应用固定化酵母同时进行发酵和分离的 CO_2气提的乙醇间歇发酵和连续发酵。从实验结果发现,无论是间歇还是连续操作,无论是改变稀释率还是改变进口底物浓度,在实验范围内,发酵速率都基本上保持常数,即,固定化酵母发酵时,发酵液中少量游离酵母的影响可以忽略,固定化酵母密度在发酵过程中不会发生很大变化。由此而导出的简化模型可以满意地关联稳态操作时的实验数据,并进而推算动态响应曲线。 相似文献
100.
毛皮类物料干燥特性模拟试验研究 总被引:1,自引:0,他引:1
采用正交试验法对不同干燥工况下毛皮物料干燥特性进行试验,给出了干燥曲线和干燥速率曲线,建立了干燥特性方程。试验方法具有通用性。通过正交分析,以干燥时间和能耗为目标给出最佳干燥工况。 相似文献