Cu-ZnO/Al2O3催化仲丁醇制备甲乙酮

用Cu-ZnO/Al2O3催化仲丁醇制备甲乙酮。研究了催化剂的焙烧温度和焙烧时间、仲丁醇脱氢反应的温度和压力以及仲丁醇的流量对仲丁醇转化率和甲乙酮选择性的影响。结果表明,催化剂的焙烧温度为300-400℃,焙烧时间为6h,脱氢反应的温度为300℃,压力为0.2Mpa,仲丁醇的流量为140mL/h时,仲丁醇的转化率和甲乙酮的选择性较好。     

8253定时/计数器方式3计数过程的实验研究

对于我系选用教材和部分参考资料关于8253定时/计数器在方式3的计数过程中表述中所存在的矛盾之处,基于武汉众友电子科技有限公司的接口实验台,提出了一个探究8253计数过程的实验方案。通过分析实验结果,指出了正确的计数过程。     

Development of a plastic injection molding training system using Petri nets and virtual reality

INTRODUCTIONAt present, plastic as a substitute for metals in products is the most important mainstay in industrial raw materials. Furthermore, plastic injection molding is one of the most common and versatile methods for mass production of complex plastic parts with excel-lent dimensional tolerance. Since the technology of injection molding has been widely applied in manu-facturing, training on injection molding is of great importance. The traditional approach is to consult some technica…     

传统几何造型艺术在现代服装设计中的立体表现

近年来,富有形式美感的几何造型服装在时装舞台上越加醒目,越来越多的设计师开始关注传统几何造型艺术在服装设计中的应用价值。如何将传统的造型艺术与现代时尚设计相结合,并创造出新的表现方式,成为研究的关键。在对几何造型的历史渊源及其相关的形式特点进行分析的基础上,对服装廓形、肌理图案、面料中的几何元素在现代服装设计中的立体表现进行分析研究,有利于探索其完美结合后的艺术和商业价值。     

新建地方本科院校课堂教学评价体系新论——基于邯郸学院“234”课堂教学评价体系个案研究

课堂教学评价体系的建构与实施对提高教学质量起着重要的引领作用。对照目前我国高校课堂教学评价体系现存的主要问题,新建地方本科院校应该以先进的教育理论和现代质量管理理论为参照,在外适型质量观的指导下,构建富有现实针对性的评价体系。邯郸学院234课堂教学评价体系在这方面进行了初步探索和研究。     

An Analysis of Foreign Language Learning Styles from the Cognitive Perspective

From the 1970s,learning styles began to enter the domain of foreign language learning researches.Foreign language learning style is often regarded as a significant factor attributing to individual differences among language learners.Nowadays,many researchers begin studying individual learners’characteristics and exploring how different learners interact with external factors from cognitive perspective.The field-independence/dependence construct became a focus.Based on previous studies,the paper is committed to analyzing the nature of FID learners.It is expected that this research can establish a well-grounded basis for following studies.     

以甘油为原料合成2,3-环氧丙醇

以甘油为原料,两步法合成了2,3-环氧丙醇,甘油和氯化氢气体在催化剂作用下氯化成3-氯-1,2-丙二醇,3-氯-1,2-丙二醇在NaOH乙醇溶液中环化为2,3-环氧丙醇。实验结果表明,冰醋酸是甘油氯化反应的最优催化剂,最佳用量为甘油摩尔数的0.2倍;环化反应中最佳摩尔比为1：1,最佳环化时间为30min。     

Effects of La^3＋on microwave dielectric properties of（Pb0.5Ca0.5）（Fe0.5Ta0.5）O3ceramics

This work investigated the microwave dielectric properties of A-site substitution by rare earth La3+in(Pb0.5Ca0.5)(Fe0.5Ta0.5)O3(PCFT) system.A single perovskite phase was obtained only when the doping content was 2%.Suitable La3+ doping improved microwave dielectric performances.Excessive La3+doping caused the formation of secondary phase,which resulted in the decreasing of permittivity εrand quality factor Qfvalues.Especially,when the doping content is 2%-5%,permittivity εrwas above 75 and Qfvalues were 6...     

3DV quality model based depth maps for view synthesis in FTV system

Depth maps are used for synthesis virtual view in free-viewpoint television (FTV) systems.When depth maps are derived using existing depth estimation methods,the depth distortions will cause undesirable artifacts in the synthesized views.To solve this problem,a 3D video quality model base depth maps (D-3DV) for virtual view synthesis and depth map coding in the FTV applications is proposed.First,the relationships between distortions in coded depth map and rendered view are derived.Then,a precisely 3DV quali...     

东亚经济弱收敛的原因:对“东盟+3”的检验

东盟和中日韩三国的经贸联系日益密切,双边在自由贸易区领域内的合作不断深化。同时也应该看到,"东盟+3"体系内的各个国家地区经济发展水平有着一定的差距,但这种差距在逐渐缩小。事实表明,在加入以经济自由度为代表的制度因素之后,"东盟+3"的收敛速度有了负的增长趋势,显然,制度因素是阻碍缩小"东盟+3"经济发展水平差距的重要因素。