首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 156 毫秒
1.
首次报道了N^3-2-氰基乙基-N^1,N^5-二乙酰基二乙基三胺的合成方法。合成此化合物的意义在于将二乙基三胺两端之氨基保护后,从其中间的N^3原子上接一条碳链,再通过这条碳链将DNA之切割基因二惭基三胺与DNA识别系统相连接,这样即可增加二乙基三胺的柔性,增大其切割活性,从而可进一步开发出一系列定位切割DNA的化学核酸酶。  相似文献   

2.
首次报道了N3-2-氰基乙基-N1,N5-二乙酰基二乙基三胺的合成方法.合成此化合物的意义在于将二乙基三胺两端之氨基保护后,从其中间的N3原子上接一条碳链,再通过这条碳链将DNA之切割基团二乙基三胺与DNA识别系统相连接,这样即可增加二乙基三胺的柔性,增大其切割活性,从而可进一步开发出一系列定位切割DNA的化学核酸酶.  相似文献   

3.
由丁二酸酐和二乙基三胺为起始原料采用熔融缩聚法合成出了端氨基超支化聚酰胺;确定了适宜的合成路线和合成反应条件,用FTIR,1H-NMR和GPC对超支化聚酰胺进行了表征。  相似文献   

4.
文章首次报道了一种含咪唑环多胺类化合物N1,N5-二(1-甲基咪唑-2-酰基)二乙基三胺的合成方法,以此化合物为基础,可以合成对称平行的发卡式多酰胺分子,以期对DNA序列进行新的特异性识别,从而开发研制新型有效的工具酶或抗癌药物。合成方法简便易行、耗时短、不需要过柱分离,每一步合成都有较高的产率。  相似文献   

5.
文章首次报道了一种含咪唑环多胺类化合物N1,N5-二(1-甲基咪唑-2-酰基)二乙基三胺的合成方法,以此化合物为基础,可以合成对称平行的发卡式多酰胺分子,以期对DNA序列进行新的特异性识别,从而开发研制新型有效的工具酶或抗癌药物。合成方法简便易行、耗时短、不需要过柱分离,每一步合成都有较高的产率。  相似文献   

6.
新型咪唑啉两性表面活性剂的合成   总被引:1,自引:0,他引:1  
以十二醇双氧乙烯基乙酸为原料,与二乙三胺反应合成了咪唑啉环,进而合成了乙酸盐型咪唑啉两性表面活性剂,测定了其水溶液的表面张力,起泡性能,临界胶束浓度,讨论了反应条件对表面活性剂性能的影响。  相似文献   

7.
用TbCl3、二乙三胺五乙酸的酸酐(简写为DTPAA)和对氨基水杨酸的钠盐(简写为PAS)在水溶液中制得了Tb^3 的三元配合物,并通过元素分析、差热-热重分析、紫外和红外光谱、荧光光谱、荧光寿命和量子产率对此三元配合物进行了表征。  相似文献   

8.
二庆茂铁甲醛与胺在无水乙醇中缩合合成了9个新型Schiff碱,通过UV和IR确证了其结构。  相似文献   

9.
以二辛胺为原料,硫酸二甲酯为烷基化试剂,CaO为缚酸剂,通过非均相的液—固反应,常压下合成了二辛基二甲基氢氧化铵,二辛胺能定量转化。将二辛基二甲基氢氧化铵与盐酸或氢溴酸中和得到二辛基二甲基季铵盐。此方法反应时间短,反应产率高,一般可达98.2%,所得产品纯度高。  相似文献   

10.
以易制备的2-(1,2-亚乙/1,3-亚丙二硫)亚甲基-3-羰基丁酸1为原料,经与氯化亚砜的氯化反应后,与胺反应成功地以较好产率(40.5%-72.0%)合成重要的有机合成中间体2-(1,2-亚乙/1,3一亚丙二硫)亚甲基-3-羰基-N-芳(烷)基丁酰胺3.  相似文献   

11.
Fantasm: The triumph of form (an essay on the democratic sublime)   总被引:1,自引:1,他引:0  
This essay attempts to counter the dreariness of postmodern critique and culture by locating the vital force of phantasy, rhetoric, argument, hope, and memory in contemporary public affairs. More particularly, it engages recent controversies about collective memory and the FDR memorial statue especially to generate a greater sensitivity to the fact that we are agents (and not just dupes) of history. The body, symbolic and material, is a core site for the history, theory, and practice of democracy, I argue, and is the hard kernel of collective identification and division. Methodologically, the essay fuses Aristotle and Lacan's ideas about phantasy as a perceptual device, which gages and creates public and personal desire, as an analytic frame for the study of public discourse.  相似文献   

12.
This article describes the findings of a qualitative study on knowledge, beliefs, attitudes, and practices towards children with spina bifida and hydrocephalus in four regions of Uganda. Focus group discussions and semi-structured interviews were held with parents of children with spina bifida and hydrocephalus, policy-makers, and service providers. Our findings describe how negative knowledge, beliefs, attitudes, and practices create barriers to treatment and inclusion of children with spina bifida and hydrocephalus and their parents in Uganda. The findings show how knowledge, beliefs, attitudes, and practices evolve over time, are both similar and differ in the various regions, and become more conducive towards accessing treatment and achieving inclusion. Sensitisation and early intervention including parents and service providers in dissemination of knowledge, rehabilitative care to set the trend for positive change and support, as well as longitudinal studies of children with spina bifida and hydrocephalus and their parents are recommended.  相似文献   

13.
Book Reviews     
Books reviewed:
Richard Edwards and Robin Usher, Globalisation and Pedagogy: Space, place and identity
Jackie Brine, Educating Women: Globalizing Inequality
David Carr, Professionalism and Ethics
Andrew Pollard and Ann Filer, The Social World of Pupil Career: Strategic Biographies through Primary School
Bernard Crick, Essays on Citizenship
Mike Bottery and Nigel Wright, Teachers and the State: Towards a Directed Profession
Stephen Heathorn, For Home, Country and Race: Constructing Gender, Class and Englishness in the Elementary School 1880-1914
Jane M. Page, Reframing the Early Childhood Curriculum: Educational Imperatives for the Future
Leslie P. Steffe and Patrick W. Thompson (eds), Radical Constructivism in Action
Patricia Broadfoot, Marilyn Osborne, Clare Planel and Keith Sharpe, Promoting Quality in Learning – Does England have the Answer?
Claire Cameron, Peter Moss and Charlie Owen, Men in the Nursery: Gender and Caring Work
Mike Cole (ed), Education, Equality and Human Rights
R. Alexander, P. Broadfoot and D. Phillips, Learning from Comparing: New Directions in Comparative Educational Research , Volume 1 Contexts, Classrooms and Outcomes
OECD, Learning to Bridge the Digital Divide  相似文献   

14.
Reviews     
Buckingham, David Moving Images: Understanding Children's Emotional Responses to Television
Aldrich, Richard (ed) In History and in Education: Essays presented to Peter Gordon
Kohli, Wendy (ed) Critical Conversations in Philosophy of Education
Griffiths, Morwenna Feminisms and the Self: the web of identity
Fryer, Marilyn Creative Teaching and Learning
Atkinson, Paul; Davies, Brian and Delamont, Sara (eds) Discourse and Reproduction: Essays in Honour of Basil Bernstein
Slee, Roger Changing Theories and Practices of Discipline
Woods, Peter and Jeffrey, Bob Teachable Moments: The Art of Teaching in Primary Schools
Best, Ron (ed) Education, Spirituality and the Whole Child
Bassey, Michael Creating Education Through Research
Higham, Jeremy; Sharp, Paul and Yeomans, David The Emerging 16–19 Curriculum: Policy and Provision
Bruner, Jerome The Culture of Education
Halsall, Rob and Cockett, Mike (eds) Education and Training: Chaos or Coherence
McBride, Rob (ed) Teacher Education Policy
Wideen, Marvin F. and Grimmett, Peter P. (eds) Changing Times in Teacher Education
Nixon, Jon; Martin, Jane; McKeown, Penny and Ranson, Stewart Encouraging Learning: towards a theory of the learning school
Gewirtz, Sharon; Ball, Stephen, J. and Bowe, Richard Markets, Choice and Equity in Education  相似文献   

15.
创新源于实践   总被引:68,自引:66,他引:68  
从理性上分析了文化的知识、思维、方法和精神4个层面的内涵及其相互关系。并提出学习和知识,思考和思维,实践和方法三者的关系。其中学习、知识是基础,思考、思维是关键,实践、方法是根本。创新来源于实践,一切文化来源于实践。在素质教育中应处理好学习、思考和实践的关系。  相似文献   

16.
作文教学的改革应该是一个系统的工程,它涉及了写作的思想与方法、过程与评价、反馈与矫正,还涉及了吸纳与输出、积累与整合、应用与拓展、发现与创新等方面的研究与改革。新课程理念下对作文的创新评价应从评价理念人本化、评价功能激励化、评价主体多元化、评价内容综合化、评价形式民主化、评价方法多样化等方面来进行,以激发学生自主写作、快乐写作的欲望,让学生在写作的实践过程中抒写自我的心灵感受,实现人格与能力的和谐发展。  相似文献   

17.
Making is a rapidly emerging form of educational practice that involves the design, construction, testing, and revision of a wide variety of objects, using high and low technologies, and integrating a range of disciplines including art, science, engineering, and mathematics. It has garnered widespread interest and support in both policy and education circles because of the ways it has been shown to link science learning to creativity and investigation. Making has taken root in out-of-school settings, such as museums, science festivals, and afterschool and library programmes; and there is now growing interest from primary and secondary educators in how it might be incorporated into the classroom. Making expands on traditions associated with Technology Education and Design-Based Learning, but differs in ways that can potentially broaden participation in science and STEM learning to include learners from communities historically underrepresented in STEM fields. STEM-Rich Making is centrally organised around design and engineering practices, typically integrating digital tools and computational practices, and positions scientific and mathematical concepts and phenomena as the materials for design. This paper takes a critical view of the claims about Making as a productive form of science teaching and learning, and reviews the current research literature’s substantiation of the ways in which Making supports students’ agency, promotes active participation in science and engineering practices, and leverages learners’ cultural resources.  相似文献   

18.
对西安市七区全民健身场所年龄分布、健身规律以及对健身功能的认知进行问卷调查,进行数理统计后,结合有关献进行分析。结果发现经济压力和生活压力,健身观念以及生活习惯,健身理论研究、健身运动的组织以及宣传等政府行为,工作性质以及工作时间等均对全民健身的开展有着不同程度的影响。建议政府、单位、社会结合,开发新运动项目、制定运动处方,并加大宣传力度,全面深入地开展群众性体育竞赛,促进全民健身从“我为”向“为我”转化,必能促进全民健身活动健康、有序地开展。  相似文献   

19.
Adopting a person-centered approach, we profiled 5th and 6th grade children's (152 boys and 161 girls) school-related beliefs about perceived task difficulty and agency beliefs in ability and effort. Five clusters were compared across key learning-related dimensions encompassing underlying worldviews (means–ends beliefs, normative difficulty, nature of ability), motivation (intrinsic, identified, introjected, and extrinsic), and adjustment (achievement and well-being): Agentic (high ability, high effort, low difficulty), Strivers (above average ability, high effort, high difficulty), Normative (average ability, effort and difficulty), Disengaged (low ability, low effort, average difficulty) and Challenged (low ability, low effort, high difficulty). The findings suggest that difficulty, perceived either as challenge or obstacle, plays an important role for the belief profiles, and that relationships with worldviews and motivation are indicative of adaptation and maladaptation.  相似文献   

20.
理查德·罗蒂立足后现代主义、解构主义、文化自由主义、相对主义和后哲学文化论,建立的协同性实用主义,批判分析哲学、现象学、传统的认识论、反映论、符合论和真理观,肯定解释学的功能与教化作用,否定客观性、绝对性、永恒性和不变性,反对理性主义、科学主义和实在论,主张解构形而上学,创立无冕哲学,提倡工具主义、约定主义、实用主义、多元主义,以及心灵与社会的协同性作用。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号