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本文主要以生活中的物理现象及学习应用为重点进行分析,结合当下生活中物理现象和课本中物理知识的重要性为主要依据,从生活中的激光、电磁波、光的颜色这三方面进行深入探索,其目的在于提高物理学习水平。 相似文献
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红岩精神蕴含和体现着中国共产党人在革命斗争中所培育和实践的崇高精神风范,是中国共产党和中华民族的宝贵精神财富。体现了无产阶级的世界观、人生观、价值观,也是高尚爱国主义情感和民族精神的集中反映。本文从红岩精神所体现的爱国主义精神、理想信念等方面分析了红岩精神在社会主义核心价值观中的地位,并阐释了其之于社会主义核心价值观的积极的作用。 相似文献
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Titanium silicalite-1(TS-1)was synthesized by a hydrothermal synthesis method with different amounts of tetrapropyl ammonium hydroxide(TPAOH)as template. The as-prepared TS-1 was characterized by scanning electron microscopy, X-ray powder diffraction, Fourier-transform infrared resonance spectroscopy, ultravioletvisible diffuse reflectance spectroscopy and nitrogen physical adsorption and desorption, and studied in the propylene epoxidation with hydrogen peroxide in a fixed bed reactor. The results showed that the amount of TPAOH had a strong influence on the grain morphology, the amount of framework Ti, and the average particle sizes of TS-1. With the increase of TPAOH amount in the synthesis(the molar ratio of TPAOH/SiO2 increasing from 0.25 to 0.45), the morphology changed gradually from ellipsoids to cubes, the particle sizes of TS-1 decreased slightly, the amount of the framework Ti increased appreciably, and the catalytic stability in the propylene epoxidation increased markedly. Moreover, all the catalysts had the same selectivity to propylene epoxide. However, when the molar ratio of TPAOH/SiO2 was further increased to 0.55, the particles became large hexagons with the size distribution in a wide range, and the catalytic stability decreased sharply although the amount of the framework Ti increased further, which can be attributed to the long diffusion paths of the reactants in the zeolite. 相似文献
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