分光光度法测定注射液中的左氧氟沙星

左氧氟沙星（levofloxacin hydrochloride）为喹诺酮类广谱抗菌药。在0．10mol／LHCl溶液中左氧氟沙星可以与FeCl,溶液反应生成酒红色络合物,在410nm处有最大吸收,采用分光光度法测定左氧氟沙星及其注射液中左氧氟沙星的含量,方法简便、快速、结果准确,可作为产品质量中间监控的快速检验法。平均回收率为106．6％。     

Predictors and outcomes of low-income fathers’ reading with their toddlers

Most studies of parent–child bookreading have focused on mothers reading to their children. Though the role of fathers in children's lives is widely emphasized, we know almost nothing about father–child bookreading, particularly among low-income families. The present study was designed to examine how often low-income fathers report reading to their children and what the predictors and effects of paternal bookreading are. The fathers in this study were participants in the national evaluation of Early Head Start (EHS) and were recruited via mothers enrolled in the EHS study. Participating fathers were interviewed at home and their children's cognitive and language development were assessed using standardized measures from ages 2 to 5. Results demonstrated a wide variety in frequency of bookreading among fathers. Fathers were more likely to read to their children frequently if they spoke English at home, if they had a high school education, and if their children had better language skills. Fathers’ bookreading predicted children's cognitive outcome. Paternal bookreading did predict children's language outcomes but only for children whose fathers had at least a high school education.     

数字化时代的人文素质教育

21世纪是数字化生存的世纪,这不仅意味着科技的发展,而且同时意味着与此紧密相关的人文发展,人的生活包括人类文明观念,将由此产生本质性的转变.也正如美国未来学家、"互联网教父"尼古拉·庞帝曾预言的,数字化是步入新世纪的人类生存的福祉,没有数字化,就没有人类的前途.     

问题教学的分析与实践

所谓问题教学,是指以问题为中心的教学,它是把教学内容化作问题,引导学生通过解决问题从而掌握知识、形成能力、养成心理品质的过程。它体现了以教师为主导,学生为主体的原则,有利于学生更好地掌握系统知识,提高探究能力。     

论成人高校改制为普通高校后的本科教学

成人高等学校的本科教学向普通高等学校本科教学的转变,是从观念到体制的变化,需要教师和管理者从教学到科研、从课堂到课外、从管理到服务进行全方位审视。只有选择创新性教学预期反应方式,在了解两种不同类型本科教学的对象之间所存在的差异的基础上,确立正确的普通高校本科教学转变思路、建立科学合理的教学保障制度、全面提升教学质量,这种转变才具有名实相符的积极意义。     

移动微型学习的内涵和结构

移动微型学习是一种运用移动设备可随时随地进行的微型学习形式.本文运用文献分析法在厘清微内容、微型学习、移动微型学习概念的基础上,对移动微型学习系统的空间结构和学习过程的叙事结构进行了深入探讨,并以此提出了未来移动微型学习发展所应注意和面临的一系列问题.     

高等院校网络教育发展状况及支撑体系探析

网络教育是20世纪教育领域的一项重要创新。作为网络教育重要组成部分的高等院校网络教育,在整个社会的关注下,取得了有目共睹的成绩。然而,高等院校网络教育也不可避免地存在许多问题和不足,如何为高等院校网络教育提供支撑体系,使其更快更好地发展,是本文所要探讨的课题。     

Polychlorinated dibenzo-p-dioxins and dibenzofurans in flue gas emissions from municipal solid waste incinerators in China

Polychlorinated dibenzo-p-dioxins and furans （PCDD/Fs） emissions in flue gas from two types of municipal solid waste incinerators （MSWIs） most commonly used in China were investigated in this study. The selected incinerators include two grate-type MSWIs： MSWI-A （350 t/d） and MSWI-B 050 t/d）, and two fluidized bed MSWIs： MSWI-C （400 t/d） and MSWI-D （400 t/d）, which are all equipped with semi-dry lime scrubber and bag filter except MSWI-D equipped with cyclone and wet scrubber （WS） as air pollutant control device （APCD）. Results indicated that the emission concentration and the international toxic equivalents （I-TEQs） of the PCDD/Fs from the stacks were in the range of 1.210-10.273 ng/Nm^3 and 0.019-0.201 ng I-TEQ/Nm^3, respectively. They were greatly lower than the emission regulation standard of PCDD/Fs in China （1.0 ng I-TEQ/Nm^3）. However, only the PCDD/Fs emission level from MSWI-C was below 0.1 ng I-TEQ/Nm^3. Although the homologue profiles were distinct, the contributions of the 2,3,7,8-subsituted congeners to the total I-TEQ were similar among all the investigated MSWIs. Two major 2,3,7,8-substituted congeners, 2,3,4,7,8-PeCDF and 1,2,3,7,8-PeCDD, account for 47% and 9% （average values） of the total I-TEQ values, respectively. The correlation between PCDD/Fs levels and composition of flue gas was also discussed.     

英国大学内部管理制度的研究与借鉴

建设科学、有效的内部管理制度,对形成大学竞争力具有重要意义。突破传统官僚制体系,建设适宜基层学术组织发展的制度环境,形成智力资本的集聚和以科研为导向的知识创新模式,是英国大学内部管理体制变化的新特点。借鉴英国的经验,我国应继续推进高校依法自主办学,发挥政府在大学资源配置方面的引导作用,进一步推动学校内部教学科研机构的整合。     

高职院校校园文化建设的现状及对策

高职院校校园文化是高校校园文化的重要组成部分.加强高职院校校园文化建设对于推进高等教育改革发展、加强和改进大学生思想政治教育、全面提高大学生综合素质等,具有十分重要的意义.文章主要对新时期高职院校校园文化建设存在的主要问题和加强、改进校园文化建设的有效途径进行了深入探讨.