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71.
Nanocrystalline solid solution CeO2-Nd2O3 powders were prepared by low temperature combustion process.Special attention was paid to the influence of the glycine/metal ratio and calcination temperature on the powders phase structure, morphology and particle size.TG-DSC curves and XRD peaks of different glycine/metal ratio show that smaller particle size can be obtained with a slightly fuel-deficient ratio.XRD results indicate that the as-prepared powders are crystallized in a single fluorite structure.The crystalline size ranges from 9 to 24 nm, which increases with the increase of calcination temperature.The lower SEM images were characterized by the spongy and form-like microstructure of the powders.Organic agent may be gradually eliminated by high temperature calcination process. 相似文献
72.
对听觉滤波器组模型进行了研究。比较分析了伽马通(Gammatone)听觉滤波器组模型和基于小波分析的高斯小波听觉滤波器组模型,分别给出了预测听阈曲线并且与标准听闻曲线进行了比较,结果表明高斯小波听觉滤波器组模型更接近实际人耳滤波效果。将高斯小波听觉滤波器组模型的预测特征响度与德国朗德(Head Acoustics)公司的Artemis软件计算出的特征响度进行分析比较,结果表明,每个特征频带的响度差值都小于0.6 sone。 相似文献
73.
Molecular imaging, as an emerging technique in current medical diagnostics, therapy and biology science, has received more and more attention in academia, industry, as well as medical practices. And the applications of nanotechnology in this field stimulate its development. This paper explores the development of the basic research and applied research on nano-enhanced molecular imaging, and does the in-depth analysis by adopting the bibliometrics method. The results show that the US is the leader in this field, who has the absolute advantages. Germany, UK and France and Japan are the followed ones. The rapidly developing Asian countries , China and South Korea might become the potential competitors. Research network analysis draws the conclusion that the other countries and regions share the same research interests with the US. The US not only take the lead in the researching number, but also directing the future orientation of this field. However, the US has not much international collaboration. The collaboration within the country and regions show that collaboration in this field is limited to the regional adjacency. Disciplinary analysis reveals that the major subjects which relate intimately to the nano-enhanced molecular imaging are chemistry, biomedical science and material science. 相似文献
74.
75.
本文基于亚硝酸根对溴酸钾氧化孔雀石绿而使其褪色的催化作用,建立了高灵敏度催化吸光光度法测定痕量亚硝酸根的新方法,测定范围为(0.026~0.300)mg/L,用于几种蔬菜样品中亚硝酸根的测定,获得了满意结果. 相似文献
76.
根据目前地基平板载荷试验中存在的一些问题.提出一些建议供工程检测人员及规范制定单位参考. 相似文献
77.
Xingguo Song Haibo Gao Liang Ding Deyou Liu Minghui Hao 《Neural computing & applications》2013,22(3-4):587-595
This paper considers the problem of global stability of neural networks with delays. By combining Lie algebra and the Lyapunov function with the integral inequality technique, we analyze the globally asymptotic stability of a class of recurrent neural networks with delays and give an estimate of the exponential stability. A few new sufficient conditions and criteria are proposed to ensure globally asymptotic stability of the equilibrium point of the neural networks. A few simulation examples are presented to demonstrate the effectiveness of the results and to improve feasibility. 相似文献
78.
X. Z. Gao S. J. Ovaska 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2001,5(4):287-296
In this paper, we give a comparison between the conventional power control scheme and soft computing-based approaches in
a mobile communications application. At the base station, the `bang–bang' control strategy and a neural network-based prediction
control method are employed. In addition, full power command transmission mode, single-bit command transmission mode, and
fuzzy logic-based power command enhancement unit are considered. Based on simulation experiments, we quantitatively evaluate
the performance of various combinations of these control methods and command transmission modes. Conclusions on the optimal
configuration are finally drawn. 相似文献
79.
为建设高效、节能、可靠的绿色环保电厂,大唐乌沙山发电厂的4号机组安装了脱硝装置.文中简述了脱硝装置的原理及工艺流程、设计参数,详细介绍了烟气脱销系统的结构及工艺特点. 相似文献
80.