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991.
地勘地质资料整理在现代矿产资源开采、地质工程建设过程中起到了非常重要的作用,直接关系着矿产资源开采质量、效率以及地质工程的安全可靠性,因此,企业应当加强重视。对地勘地质资料整理的重要性进行了分析,并在此基础上,就其整理方法及具体应用提出了一些观点和建议,以期为我国地勘地质行业的发展提供参考。 相似文献
992.
993.
利用芬顿(Fenton)试剂的催化氧化性对焦化废水进行初步的处理,使其CODcr值除去率达80%以上,再用活性炭进行深度处理,使其CODcr值<40mg·L-1,总除去率达98%以上. 相似文献
994.
995.
996.
虚拟实验应用日益广泛,而支持虚拟实验的相关技术成为了研究热点。分析了虚拟化学实验及其在未来虚拟现实技术上的发展趋势,综述了U-nity3D技术、增强现实技术和Kinect体感交互技术的理论基础以及在虚拟化学实验中的应用与发展,以虚拟技术融合的方法为导向,仿真化学实验的实时环境,使虚拟实验简单化、直观化。展望了虚实融合技术在虚拟实验领域的应用前景。虚实融合技术有利于推动虚拟化学实验朝智能化发展,是虚拟实验改革的一个新起点。 相似文献
997.
998.
Hexamethyldisilazane was used as the starting material to synthesize N,N′‐bis(hydroxydiphenylsilanyl)tetraphenylcyclodisilazane (BHPTPC). By condensation polymerization of BHPTPC with α,ω‐bis(dialkylamino)dimethylsiloxane, a series of alternate copolymers containing N,N′‐bis(diphenylsilyl)tetraphenylcyclodisilazane was synthesized. GPC studies show that the highest molecular weight was obtained at a ratio of 1.005 : 1 (BHPTPC: α,ω‐bis(dimethyl amino)dimethylsiloxane). Data of DSC indicate that the temperature of glass transition (Tg) and temperature of melting point (Tm) decreased with the increasing of dimethylsiloxane segments units. Three stages of degradation were found in the thermogravimetric analysis curves. The activation energy of the copolymer (with m = 2, 3, and 7) was calculated by using Flynn–Wall–Ozawa method. The activation energy of the copolymer with m = 2, 3, and 7 at second stage is 214, 211, and 184 kJ/mol, respectively. Isothermal gravimetric analysis shows that for the same temperature and the same time, the weight loss of the alternate copolymer was greatly less than that of common polydimethylsiloxane. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 611–617, 2007 相似文献
999.
Lijin Xie Junfeng Ma Jun Zhou Zhongqiang Zhao Hua Tian Yonggang Wang Jiantao Tao Xiaoyi Zhu 《Journal of the American Ceramic Society》2006,89(5):1717-1720
Well-crystallized bismuth tungstate (Bi2 WO6 ) powders with different morphologies were successfully synthesized via a low-temperature molten salt method. The powders were characterized by X-ray diffraction, transmission electron microscopy, and UV-Vis, respectively. It was found that the variation of morphology of the obtained Bi2 WO6 powder mainly depends on the different reaction temperatures and the weight ratio of LiNO3 –NaNO3 salt to precursor. In addition, the UV-Visible absorption spectra showed that the synthesized powders had strong light absorption properties not only in the ultraviolet light but also in the visible light region. 相似文献
1000.
The service mashup programming paradigm is a blooming faction of service oriented Architecture for developing web applications. A mashup application constructs its functionality by combining data, presentation and functionalities obtained from online services published by service providers such as Google and Amazon. This paradigm significantly facilitates the implementation of application and reduces the workload. But it also makes the application rely on the availability and qualities of the online services which beyond its control in which case the robustness of the system requires more concern. This paper proposes a formal model to specify and analyze the behavior and robustness of service mashups under a certain environment where some services may become unavailable. The specification contains both system specification and environment situation. Refinement theory are employed to specify the correctness of dynamic service selection. The framework realizes the service selection by allowing virtual service requests to be handled by any online service having consistent interface and refined functionality. The framework provides a clear definition of the robustness of mashup systems and proposes several rules as well as approaches to preserve the robustness during the development and maintenance of the system. 相似文献