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921.
当前以计算思维能力培养为切入点的大学计算机课程改革工作已进入一个新的阶段,如何改革计算机基础教学以适应当前形势的发展,是计算机基础教学面临的挑战。以计算思维为导向,对应用型本科院校大学计算机基础课程的目标定位、教学内容、教学过程等教学环节作改革式探索。 相似文献
922.
Hongcang Zhou Baosheng Jin Zhaoping Zhong Yaji Huang Rui Xiao Youfei Zheng 《Korean Journal of Chemical Engineering》2007,24(3):489-494
The coal partial gasification catalyzed by limestone, sodium carbonate and dolomite was studied using a bench-scale atmospheric
fluidized bed in the presence of air and steam at 900 °C. The effects of limestone, sodium carbonate and dolomite on composition,
heating value, gas yield of product gas and carbon conversion in the catalytic coal partial gasification have been examined.
The experimental results show that the catalysts can effectively improve the gas quality, the heating value and the gas yield
of product gas and carbon conversion. The catalytic effect of sodium carbonate is better than that of limestone and dolomite.
The increase of limestone loading can enhance the quality of product gas, such as the content of combustible gas, the high
heating value and the gas yield, during coal partial gasification.
This work was presented at the 6
th
Korea-China Workshop on Clean Energy Technology held at Busan, Korea, July 4–7, 2006. 相似文献
923.
江进 《电脑与微电子技术》2014,(17):32-35
《C语言程序设计》是高职院校工科类专业重要的专业基础课程,培养学生对程序设计思想的认识、理解,为后续专业课程的继续学习和深造打下基础。阐述CDIO的概念,《C语言程序设计》课程在农林类高职院校的教学现状,并提出如何根据学生特点,将CDIO理念运用到教学中,进行课程体系、教学内容、教学方法和考核方式的改革和效果。 相似文献
924.
925.
I. S. Kaynarskiy I. G. Orlova Ye. V. Merkulova 《Refractories and Industrial Ceramics》1961,2(1-2):59-64
Conclusions The pressing of argillaceous raw material reduced to a thermoplastic state by heating produces ultradense refractory of high quality.Standard brick made of 50% Vladimirovka kaolin, 3-1 mm, and 50% Chasov-Yar clay finer than 0.5 mm, pressed to 100 kg/cm2 and at about 1380°, containing 40% Al2O3, shows a high degree of slag resistance and spalling resistance, and has an apparent porosity of 3% bulk density 2.52 g/cm3. 相似文献
926.
Taigo Takaishi Masahide Takahashi Jisun Jin Takashi Uchino Toshinobu Yoko Masahide Takahashi 《Journal of the American Ceramic Society》2005,88(6):1591-1596
Structure of x PbO–(100− x )SiO2 ( x =25–89) glasses has been investigated by means of the X-ray and neutron diffraction and 29 Si MAS NMR measurements. In the radial distribution functions of all the glasses, the Pb–O correlation was observed at 0.23 nm, indicating that the PbO3 trigonal pyramids units do exist in the whole glass forming composition range. Furthermore the existence of the first Pb–Pb correlation at ∼0.385 nm in the whole composition range suggests that the basic structural unit is considered to be a Pb2 O4 unit, which consists of the edge-shared PbO3 trigonal pyramids. These results strongly imply that the Pb2 O4 units participate in the glass network constructed by SiO4 tetrahedra even at low PbO content. Differing from other lead-containing glass systems, these structural characteristics of Pb ions in the PbO–SiO2 glass system are responsible for the extremely wide glass-forming region. 相似文献
927.
运动颗粒团一维连续成像分析系统 总被引:2,自引:0,他引:2
本文开发了FLOTU-I型多相流径向密度连续测量和成像系统,这一系统采用石英光纤传像束为传感器,通过微机I/O控制发光二极管顺序发光,A/D高速数据采集对传感器进行高速扫描,实现了大视场下两相流的连续测量和成像过程,并将它用于观察分析循环流化床中气固两相流动行为,在内径为186mm的循环流化床内测得了颗粒团图像。 相似文献
928.
用富里哀变换红外光谱法原位跟踪不饱和聚酯树脂固化反应的动态过程。该方法能直接反映分子结构的变化,迅速准确地采集数据,尤其适用于快速反应体系。 相似文献
929.
细颗粒循环料腿的自力平衡原理及实验研究 总被引:3,自引:0,他引:3
本文介绍了一种固体细颗粒循环料腿的自力平衡结构模型(单气路式)及其工作原理,对该结构模型进行了流体力学分析,并分析了各种因素对自力平衡效果的影响趋势。在冷态模型装置上进行的实验测定验证了料腿的自平衡效果,并获得了与理论分析相一致的结论。由于该结构简单,无机械运动部件,并且易满足耐高温、耐高压及耐磨损等性能要求,特别是它能在较宽的工作范围内使料腿自力稳定,它的应用可望改善固体料循环控制的可操作性,从而对特定的工作系统有利。 相似文献
930.
Ye Wan Wenhui Guo Jin Xiao Dazhou Yan Xiong Zhao Shuhu Guo Jianhua Liu Qifan Zhong Tao Yang Yu Zhao Xin Chang Xin Gao 《中国化学工程学报》1982,28(9):2248-2255
Ultra-high-purity silicon tetrachloride (SiCl4) is demanded as an electronic-grade chemical to meet the stringent requirements of the rapidly developing semiconductor industry. The high requirement for ultra-high-purity SiCl4 has created the need for a high-efficient process for reducing energy consumption as well as satisfying product quality. In this paper, a mass of production technology of ultra-high-purity SiCl4 was successfully developed through chlorination reaction in the ultraviolet (UV)-based photo microreactor coupled with the distillation process. The influences of key operational parameters, including temperature, pressure, UV wavelength and light intensity on the product quality, especially for hydrogen-containing impurities, were quantified by the infrared transmittance of Fourier transform infrared spectroscopy (FT-IR) at 2185 cm-1 and 2160 cm-1 indicating that characteristic vibrational modes of Si—H bonds, as well as the operating conditions of distillation were also investigated as key factors for metal impurities removing. The advanced intensification of SiCl4 manufactured by the integration of photo microreactor and distillation achieves the products with superior specifications higher than the standard commercial products. 相似文献