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991.
刘寿堂 《Canadian Metallurgical Quarterly》2011,(10)
开办农民工夜校是提升农民工素质的有效途径.分析了建筑业农民工夜校开展法制教育的意义,阐述了建筑业农民工夜校法制课程教学应遵循的原则、教学内容的安排和教学手段、方法的选择. 相似文献
992.
993.
A new method for calculating the eigenmodes of gyrotron resonators is presented. With this method, the resonant frequency, Q-factor and field profiles of the eigenmodes are determined through finding the minimum value of a function of two variables, namely the resonant frequency and the Q-factor. Compared with the traditional calculation method, the new method predicts a significantly higher Q-factor of the eigenmodes. 相似文献
994.
Hydrophobic titanium dioxide (TiO2) was successfully grown on a wood surface using a hydrothermal method. Energy dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and water contact angle (WCA) were employed to characterize the features of grown TiO2 and its hydrophobicity. EDS, XRD, and FTIR proved that anatase TiO2 chemically bonded to the wood surface through the combination of hydrogen groups during the hydrothermal process. The values of WCAs manifested that the hydrophobicity of the treated wood was mainly dependent on specific reaction conditions, especially on reaction pH value and hydrothermal temperature. The highest WCA reached 154° when the hydrothermal temperature was 130 °C. The treated wood thus possessed a superhydrophobic surface. 相似文献
995.
This study builds the interdisciplinary knowledge network of China, which is used to catch the knowledge exchange structure of disciplines, and investigates the evolution process from 1981 to 2010. A network analysis was performed to examine the special structure and we compare state of the networks in different periods to determine how the network has got such properties. The dataset are get from the reference relationship in literature on important Chinese academic journals from 1980 to 2010. The analytical results reveal the hidden network structure of interdisciplinary knowledge flows in China and demonstrate that the network is highly connected and has a homogeneous link structure and heterogeneous weight distribution. Through comparing of the network in three periods, that is 1981–1990, 1991–2000 and 2001–2010, we find that the special evolution process, which is limited by the number of nodes, play an important influence on interdisciplinary knowledge flows. 相似文献
996.
997.
In this paper, an anti-fouling composite coating was fabricated by blending zinc-graphite alloy powders with epoxy-silicone resin and characterized by EDS, SEM, XRD and ion titration. Compared with stainless steel and epoxy-silicone resin coating, the composite coating significantly inhibited the deposition of CaCO3 fouling. Only a small amount of fouling was observed on the surface of composite coating after it was immersed in CaCl2/NaHCO3 solution. The galvanic corrosion of zinc-graphite powders could release Zn2+ ions, which can reduce partially the nucleation and crystal growth rate of CaCO3 on the surface of composite coating. It was found that the morphologies of CaCO3 fouling changed from calcite to aragonite as the existence of composite coating. Meanwhile, CaCO3 fouling was prone to precipitate in bulk solution rather than on the surface of composite coating. 相似文献
998.
Subramanian Palaniappan Yu-Tsern Chang Chung-Ming Liu Paramasivam Manisankar 《Materials Chemistry and Physics》2011
A facile and sustainable mechanochemical route for the synthesis of undoped polydiphenylamine (PDPA) and inorganic acid doped nanostructures are reported. Field emission scanning electron microscopic (FESEM) images highlighted the formation of distinctly different nanostructures for each of the inorganic acid doped PDPA. Elemental analysis carried out for the polymers revealed the presence of more repeating units in their backbone. The X-ray diffraction (XRD) results of the as-prepared PDPA nanostructures indicated the high degree of crystallinity ever reported for PDPA. Spectroscopic profile of the polymers showed that the prepared PDPA is in a doped conducting form. Electrochemical studies performed for the polymeric particles ascertained the redox behaviour and the good electrochemical activity of obtained PDPA samples. The probable mechanistic aspect behind the formation of PDPA nanostructures through this simple and efficient route is discussed. 相似文献
999.
1000.