Cl-SBA-15介孔分子筛的直接合成

以聚乙二醇-聚丙三醇-聚乙二醇三嵌段聚合物(P123)为模板剂,在酸性条件下采用直接合成法合成了有序性较高的含氯丙基的介孔分子筛材料。用小角XRD、FTIR及DTA对样品进行了表征。考察了不同老化温度对样品合成的影响,表明高温条件下老化所得到的样品具有较好的孔道结构。     

FeAPO-11分子筛催化氧化水溶液中苯酚的性能

以水热晶化法合成了铁磷铝分子筛FeAPO-11,并用X射线衍射分析(XRD)、扫描电镜(SEM)、紫外-可见光漫反射(UV-Vis)等对样品进行了表征,结果表明,所合成的FeAPO-11分子筛样品结晶度高,且Fe3 进入到了分子筛骨架中.进而研究了以FeAPO-11为催化剂,H2O2为氧化剂对水溶液中苯酚的催化氧化性能:在苯酚初始浓度质量200 mg/L、H2O2添加量1200 mg/L、pH值5.0、处理温度60℃、处理时间240min时,苯酚去除率达到88.72%,总有机碳(TOC)去除率达52.5%,析出到溶液中的Fe3 浓度为0.213 mg/L.重复性实验表明,催化剂的稳定性较好.     

磷酸介质中Fe/SBA-15的合成及其催化性能

在磷酸介质中,通过水热合成法合成介孔分子筛SBA-15,再用浸渍法制备Fe/SBA-15催化剂,并采用XRD,N2-BET,FT-IR和UV-Vis对合成的样品进行表征,结果表明Fe成功负载到SBA-15上,并且合成的Fe/SBA-15催化剂对H2O2氧化环己酮生成己内酯的反应具有催化作用.     

索氏抽提对HMS合成的影响

以溶胶凝胶法室温下合成了HMS分子筛原粉(DDA-HMS),考察了索氏抽提法脱膜过程中的抽提条件对HMS中孔结构及有序度的影响,X射线衍射(XRD)、傅立叶红外(FTIR)、扫描电镜(TEM)、X射线光电子能谱(XPS)及失重与差热(TG-DTA)分析表明:不同的抽提溶剂和抽提时间对HMS材料的结构具有不同程度的影响,并首次发现以丙酮抽提DDA合成的HMS具有最稳定的中孔结构和较高的中孔有序度.     

几种Keggin型多金属氧酸盐的合成及性质研究

合成了几种缺位型(1:11及1:9)型多金属氧酸盐,利用IR、UV对其进行了表征,并且研究了其热稳定性,结果表明:所有的样品均具有keggin结构,且由于缺位结构的存在,热稳定性也下降.     

钛硅溶胶后移植法制备Ti-KIT-1介孔分子筛

采用钛硅溶胶后移植法,合成了高负载钛的介孔分子筛Ti-KIT-1。利用X射线粉末衍射（XRD）、紫外可见漫反射（UV-vis）、低温N2吸附-脱附、热分析等手段对样品进行了表征,并通过环己烯环氧化反应考察了催化剂的催化性能。实验结果表明：Ti-KIT-1分子筛仍保持完好的介孔结构,但比表面积、孔容有所减少,孔径增大。后移植法钛分子筛骨架中存在四配位钛,且表现出良好的催化活性,其中以Si/Ti=5的样品Ti-KIT-5最好,H2O2的转化率达到96.5%。     

静置水解时间对Al-SBA-15介孔分子筛结构的影响

在磷酸介质中,以异丙醇铝为铝源,采用直接合成法合成出Al-SBA-15介孔分子筛.采用XRD、N2吸附-脱附、FT-IR等表征手段,考察了静置时间对Al-SBA-15介孔结构和性能的影响.     

低成本ZSM-5型沸石分子筛的合成及其吸附性能

以廉价的工业废弃物粉煤灰作为初始原料,四丙基氢氧化铵（TPAOH）为模板剂,分别采用两种合成方案制备出微孔分子筛ZSM-5样品。该法相较传统水热法,原料价廉易得,制备工艺简单。通过XRD、SEM、TR等手段对样品进行表征,发现两种方案均合成出了较高质量的ZSM-5,但形貌分别为薄片型和长六方体型。最后考察了其对水中Cr（Ⅵ）离子的吸附性能,结果表明合成的ZSM-5型样品对Cr（Ⅵ）离子有较好的吸附性能。     

介孔分子筛MCM-41对铅离子吸附性能研究

采用十六烷基三甲基溴化铵(CTAB)作模板剂,正硅酸乙脂(TEOS)为硅源,氨水(NH3.H2O)为碱性介质的条件下在常温下快速合成出了介孔分子筛MCM-41。采用X射线衍射(XRD)对合成样品进行了表征,XRD结果表明合成的MCM-41具备高的结构规整度。将该MCM-41作为吸附剂,对水中铅离子的吸附进行了研究。实验结果表明:MCM-41用量、吸附时间、吸附温度和pH值均影响其对铅离子的吸附率;其吸附动力学符合准二级动力学方程式;其等温吸附行为可以用Langmuir等温线来描述。     

α-NaYF_4:Yb,Er纳米粒子的水热合成及表征

用W/O微乳液水热制备Yb,Er掺杂α-NaYF_4上转换纳米粒子,并对合成的产物α-NaYF_4:Yb,Er纳米粒子进行了X射线衍射(XRD)、扫描电镜(SEM)、傅里叶变换红外(FTIR)、上转换发光表征. XRD分析表明产物晶格常数a0为5.423?,SEM、FTIR分析证明粒子表面覆盖着一层CTAB.通过研究上转换发光证实了α-NaYF_4:Yb,Er纳米粒子中Er离子的电子跃迁从~2H_(11/2),~4S_(3/2)——~4I_(15/2)和~4F_(9/2)——~4I_(15/2)均为三光子过程.     

上海高中生对集中量数的理解

在Watson统计素养三层次框架的基础上形成了关于集中量数理解的3个水平的思想框架,利用该框架编制的测试卷对来自上海某重点高中155名学生和某普通高中176名学生的测试和其中11名学生的访谈,发现大部分学生能正确计算集中量数,能结合实际问题背景使用恰当的集中量数,但在对所使用的集中量数进行解释时有较大困难.这些学生对众数和平均数的掌握要好于中位数.重点高中学生对集中量数的理解水平在统计意义下显著好于普通高中学生.     

因特网信息资源质量的评价标准

本文介绍了一个因特网信息资源质量的评价标准架构。该标准架构由美国乔治亚州大学项目专家组开发，内容包括11种范畴、125项评价指标。该标准架构具有系统全面、结构严谨和条理清楚等特点．对有效评价和利用因特网信息资源提供了一个科学的参照系。     

Teaching as a collective work: analysis,current research and implications for teacher education

This article investigates teaching as collective work. The goals, functions and forms of teachers' collective work and changes in the professional representations or repertoire of actions through collective activity are identified. A synthetic framework is outlined and shown to be useful in addressing the data, by revealing the importance of interactions in professional competence acquisition. The article relates this framework to data collected from new teachers in the induction year in Scottish secondary schools (age range of pupils 11–18 years) and discusses the relationship of collective work to competence standards. Some issues for teacher educators and further research questions are identified.     

Examining secondary school students’ views of model evaluation through an integrated framework of personal epistemology

The aim of the study was to investigate students’ views of model evaluation through the lens of personal epistemology. We developed an integrated analytical framework by combining a developmental framework, including absolutist, multiplist, and evaluatist, with a multi-dimensional framework, including limits of knowing, certainty of knowing, and criteria of knowing. Furthermore, we examined the potential influence of the question contexts and the students’ grade levels. A total of 188 secondary school students were surveyed. Students answered two sets of model evaluation questions based on two scientific contexts. After reading the information about the two models, the students had to choose from three epistemic assumptions and then provide written justifications explaining their choice of assumptions. Quantitative and qualitative analyses were conducted for the multiple-choice questions and the written responses. In both contexts there were higher percentages of 11th-grade students choosing the evaluatist assumptions than the eighth-grade students. For students choosing multiplist and evaluatist assumptions, the 11th-grade students were more likely than the eighth-grade students to think in terms of pragmatic and evidential criteria as the criteria of knowing. Different contexts of the questions evoked different views of model evaluation particularly regarding the limits of knowing. Four additional categories of epistemic levels also emerged from the data. This study provides a new framework for understanding students’ thinking about model evaluation. Implications and suggestions for future research are provided.

     

面向初中数学课堂的高阶思维内涵框架构建

高阶思维是基础教育关心的核心议题之一,但课堂中高阶思维的培养依旧存在较大的提升空间。“面向初中数学课堂的高阶思维内涵框架”,包含11项思维特征,归属于策略型思维、批判型思维、创新型思维三大类型。策略型思维强调学生在解决开放的、非常规的问题时是有策略的,不是盲目的。批判型思维强调学生表现出辨别、评估等能力。创造型思维强调学生产生的新观点、方法等。     

Nature Center Purposes and Values

Abstract

Using the experiences and perspectives of practicing environmental educators, the author identified the elements that contribute most to effective environmental education. First, interviews were conducted with 18 experienced environmental educators from 11 states. Factors that appeared fundamental to the teachers' successes were assembled into an initial elements-of-success framework, consisting of 42 elements arranged in 3 categories: teaching conditions, teacher competencies, and teaching practices. The framework was then sent in survey form to environmental educators across the country. The survey yielded strong and consistent confirmation that environmental educators across the country believe the framework provides a valid and useful representation of the major elements that contribute to successful environmental education.     

Impact of a Content Selection Framework on Portfolio Assessment at the Classroom Level

Among the various alternative approaches to student evaluation, portfolio assessment has been shown to have considerable potential in terms of its use in the evaluation of higher-order, cross-curricular skills. Despite this favourable outlook, it may nevertheless remain a passing fad due to the lack of a conceptual content selection framework and difficulties surrounding its implementation within the classroom setting. The present study reports on the conceptual issues that arose when a generic content framework was used to guide the selection of entries for assessment purposes. The framework proposed the systematic collection of evidence of the cognitive, affective, behavioural, metacognitive and developmental dimensions of students' mastery of a specific competency. Data were drawn from 11 case-studies of portfolio applications by teachers from eastern Ontario, Canada. It was found that the effective integration of the portfolio into teaching and assessment practices depended largely on the flexibility of the framework and, to some extent, on the type of training or support provided to the teachers.     

钱学森对现代科学技术体系总体框架的战略思考

钱学森坚持以马克思主义为指导,运用系统方法构筑了现代科学技术体系,甚至人类知识体系的总体框架。马克思主义哲学体系是现代科学技术体系的指导思想;前科学技术体系是现代科学技术体系得以丰富和发展的深厚土壤;现代科学技术体系由11个要素三个层次构成。11个科学技术大部门划分的创新之处主要在于运用＂矛盾论＂,从着眼点和侧重点之不同来研究整个客观世界;三个层次的划分的创新之处主要在于运用＂实践论＂,从理论与实践结合的紧密程度来划分的。现代科学技术体系具有整体性和开放性两个突出的特点。现代科学技术体系具有重大的战略意义。     

中学语文教师专业知识来源调查与分析

本研究把教育理论知识、课程知识、学科知识和学科教学法知识作为教师专业知识的基本框架,以问卷调查的方式请中学语文教师评价11项来源对他们的专业知识发展的促进作用。结果显示:中学语文教师认为,"自身教学经验与反思"、"和同事的日常交流"与"自学课外书刊"是专业知识发展的非常重要的来源,"教学观摩活动"、"教育见习与实习"是比较重要的来源,而"在职专业培训"、"入职后的学历补偿教育"和部分职前教育课程对专业知识发展的作用并不明显。基于以上研究发现,提出了促进中学语文专业知识发展的建议。     

African American Students in Counselor Education Programs: Perceptions of Their Experiences

The authors explored 11 African American doctoral students' perceptions of their experiences in counselor education programs, and their findings are presented. Using a phenomenological methodological framework, the authors investigated the various systems of support that students use as they navigate their respective programs. Human agency was the theoretical framework for this study, and 4 themes emerged from the data: assertiveness, more experienced African American students, race‐based organizations, and personal and professional care from advisors. Implications for students and counselor education programs are discussed.