农村义务教育投入体制存在的问题与对策

农村义务教育是我国教育的基础和主体.在义务教育的实施过程中农村基础教育面临着更多的矛盾和问题,种种矛盾和问题的存在成为制约农村教育发展乃至整个社会经济协调发展的重要因素.而农村义务教育改革集中于教育投入体制的改革,即教育经费投入是农村教育发展的中心问题.本文试图就此问题作出一些探讨.     

ISP器件在数字电路实践教学中的应用

介绍了ISP（In-System Progammability,在系统可编程）器件，及ISP器件用于数字电路实践教学的方法。     

机电模拟与分析力学

介绍了机电模拟以及用分析力学来解决机电类问题的方法，并举例说明了其应用。     

校务公开与高校思想政治工作

加强高校教职工的思想政治工作是促进学校改革和发展的需要.校务公开正是新时期加强高校思想政治工作的新方法和新途径.为此,要明确校务公开的意义、内容及形式,研究探讨校务公开与思想政治工作的相互关系,进而加大校务公开的力度,增强思想政治工作的深度.     

Synthesis and Characterization of Co-Doped Brookite Titania Photocatalysts with High Photocatalytic Activity

Transition metal-doping could effectively extend the light response range of TiO _2 photocatalysts from the ultraviolet(UV)to the visible region.Co-doped brookite titanium dioxide(Co–TiO_2)photocatalysts were synthesized via the hydrothermal method with titanium tetrachloride as the raw material and cobalt chloride hexahydrate as the dopant.The prepared Co–TiO_2 photocatalysts were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),Raman spectroscopy,X-ray photoelectron spectroscopy(XPS)and UV–Vis diffuse reflectance spectroscopy(UV–Vis DRS).The photocatalytic activities of Co–TiO _2 photocatalysts were evaluated by photocatalytic degradation of isopropanol alcohol(IPA),a typical volatile organic compound(VOC),under visible light.The influences ofdifferent Co doping rates,initial concentrations of IPA gas and the amounts of photocatalyst addition were also studied.At the same time,the enhancement mechanism ofcobalt ions as a trap for photogenerated holes was discussed.Thus,we found the optimum doping rate,initial concentration of IPA gas and amount of photocatalyst to add.The results show that the mesoporous Co–TiO _2 photocatalysts possess smaller size particles,larger specific surface area,lower forbidden bandgap energy(Eg)and better photocatalytic activity than pure brookite TiO _2.When the doping of Co was 7% by mass,the initial concentration ofIPA gas was 1.0×10~(-6 )mol/L and the addition of Co–TiO_2 photocatalysts was 50 mg,the best photocatalytic activity was achieved.Furthermore,the degradation rate ofIPA was up to 91%,which shows great potential for waste water treatment.     

远程课程的质量保证与效果评价

香港公开大学是一所开放和远程大学,非常注意资讯技术在教育中的有效运用。然而,大学的理念是:资讯技术能使远程教学的传递多元化,但远程教育的成功依赖于优质的课程和良好的学生学习支援。本文着重介绍香港公开大学远程课程的开发、质量保证以及效果评价。作者认为,无论是采用印刷媒体,还是电子教学,都需要依据有关的教学和学习理论,根据学生的学习方式,进行良好的教材设计和编写。然而,现代技术的运用有助于大中华的远程教育学者们进行合作和联合,共建和共享优质课程,从而服务于人类与社会。     

装饰中的秩序感

无论变化与统一、对比与调和、节奏与韵律、放射与回旋,都表现了一种秩序性,秩序是装饰之美的尺度。秩序是装饰之美的内在尺度。秩序代表着和谐,代表着变化以及变化后的统一,它始终与稳定和永恒性相联系。     

苏轼谐谑诗探源

诗本正体,自古皆以“温柔敦厚”为准绳和规矩。然东坡诗中有大量的戏谑调侃之作。诗作如此谐谑,颇值人们注意和研究。在界定了谐谑诗的内涵外延并探明谐谑诗源流后,本文着重分析苏轼谐谑诗之源:性格和经历是影响苏轼创作谐谑诗重要的内、外因素,对前贤的学习和继承是影响其创作的重要条件,而创作思想则影响了他谐谑诗创作的内容、技巧、风格等。     

建构主义学习理论的认识论特征分析

文章从激进建构主义和温和建构主义维度分析建构主义在认识论上的特征,接着分析了几种主要学习理论的认识论特点,指出从认识论角度看,建构主义是一种既不同于主观主义也不同于客观主义的第三种认识论,是一种介于主观主义和客观主义之间的认识论。最后分析建构主义学习理论作为教育技术学理论基础时应注意的问题。     

Characterization and photocatalytic activity of mixed nanocrystalline TiO<Subscript>2</Subscript> powders prepared by xerogel-hydrothermal method in different acid solutions

TiO₂ nanoparticles(NPs)were prepared via the hydrothermal route of TiO₂ xerogel in nitric acid, hydrochloric acid and acetic acid. The physico-chemical properties of the powders were characterized by X-ray diffraction(XRD)and N₂ adsorption desorption techniques. The effects of the different acids on the structure(crystal phase)and texture(primary particle size and porosity)of the TiO₂ powders were explored. Results indicated that acetic acid facilitated the formation and stability of pure anatase phase. On the other hand, nitric acid and hydrochloric acid led to the transformation from anatase to rutile. The catalyst synthesized via the hydrothermal route of TiO₂ xerogel in the low concentration hydrochloric acid solution(Ti-HCl-0.15)had the highest photocatalytic activity than the catalysts obtained in the other two acid solutions. The effects of the different acids were discussed in terms of acid strength, chelating effect and the thermal stability of the adsorbed acidic anions.