摘要：环境工程是环境科学的一个重要分支,它是研究运用工程技术和有关学科的原理和方法,保护和合理利用自然资源,防治环境污染,改善环境质量的学科。随着经济的发展,科学技术力量的提高,计算机辅助设计在环境工程中也得到了广泛的应用,已经成为提高产品及工程设计水平,缩短产品开发周期,提高劳动生产率、降低消耗的重要手段。本文概括了计算机辅助设计的特点,分析了其在环境工程中的应用情况,指出了计算机辅助设计在环境工程应用中存在的问题和发展方向。

摘要：随着部分高职学校对音乐的重视程度逐渐升高,其中学生对音乐的实践技能是否有很好的掌握,直接关系到未来学生就业及学校音乐专业的发展。因此,高职音乐教育中,对实践技能需要构建一套合理有效的教学体系,保障实践教学能够顺利地进行。对高职音乐教育中实践技能教学方法进行简单叙述。

摘要：Four kinds of iron oxide pigments were added into wood-fiber/high-density-polyethylene composites （WF/HDPE） at three different concentrations, to determine the effects of pigments on the changes in the color and mechanical properties of the composites before and after UV accelerated weathering. HDPE, wood fibers, pigments and other processing additives were dry-mixed in a high-speed mixer. The mixtures were extruded by two-step extrusion process with a self-designed twin-screw/single-screw extruder system. Color of the samples was determined according to CIE 1976 L^＊a^＊b^＊ system by a spec- trophotometer and the bending properties were tested to evaluate the mechanical properties before and after accelerated UV weathering. The result shows that the modulus of elasticity of WF/HDPE did not obvi- ously changed after incorporating with the pigments, but the bending strength increased. After accelerated aging for 2000 h, both color and mechanical properties significantly changed. Iron oxide red and black performed better than the other two pigments, and the pigments dosage of 2.28% in the composites is favourable.