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61.
针对传统实验“二元合金相图”在实验中存在的操作困难,精准度差和环境污染等问题,改用熔点较低的物质制作同液相图,用凝固点降低测定装置系统制作步冷曲线,采用燃烧热实验贝克曼温度测定装置实现了样品冷却过程温度数据的在线采集及步冷曲线的同步显示,改进后实验温度精度由0.2℃精准到0.001℃,实验相对误差由原来约3%降到约1.5%,操作更简便易行,且用药量减少,实验时间短,安全,基本无污染物存在与排放,可以替代原金属相图实验.  相似文献   
62.
王朔小说是20世纪80年代重要的文学现象,其“新京味儿”语言也同样是20世纪小说中重要的语言形象。和以往的“京味儿”语言相比,这种语言形象不提供道德参考系数,将口语、调侃作为解构价值规范的策略,以获得游戏生活的快感为唯一的目的。这种语言形象产生于中国特定的历史语境和文化转型的缝隙之中。  相似文献   
63.
研究相空间中二阶非完整力学系统的Lie对称与守恒量.首先利用系统运动微分方程在无限小变换下的不变性建立Lie对称的确定方程和限制方程,得到Lie对称的结构方程和守恒量;其次研究上述问题的逆问题;最后举例说明结果的应用.  相似文献   
64.
ABSTRACT

A successful transition from preschool to school demands continuity in education between the institutions: continuity in pedagogy, values and institutional structures. One way to achieve continuity is to learn how to do boundary work in the borderline of two activity systems. This article examines what kinds of discourses frame the problem-solving process in the context of inter-professional collaboration. The data consists of video-recorded, inter-professional discussions in the 2012–2013 (a total of 22.5?h). The project, called Flexible Preschool and School, aims to develop a new model for a smooth transition to school. In the project, professionals from preschool and school create joint activities and co-teaching, which is assumed to bridge the gap between pedagogies and assure the continuity of learning. The professionals’ cultural thoughts in different kinds of problem-solving situations become visible in the discourses produced in the talk. These discourses describe their capacity for solving shared problems. Creating new innovations demands an understanding that complex problems require diverse knowledge. Considering the shared knowledge as valuable enough to put into practice is the way to create new forms of problem-solving. This is implemented by taking on the responsibility to be an active actor.  相似文献   
65.
相平衡与CO2在水中的扩散速率--CO2排水集气法   总被引:1,自引:0,他引:1  
根据相平衡等的有关计算可知,常压下CO2溶于水的过程为物理吸收,CO2的饱和水溶液为稀溶液,而且溶液里碳酸的生成和电离可以忽略不计。CO2在水中的扩散系数非常小,其数量级为10^-5cm^2/s,在CO2排水集气法操作中,CO2气体不被水吸收。  相似文献   
66.
ABSTRACT

The presence of learning gardens in Spain is growing, and the current scenario is highly diverse in relation to issues such as participatory models or purposes, among others. In the context of the 1st National Meeting on organic learning gardens, we convened eight expert practitioners in a focus group. Their discourse was analyzed through content analysis, after which four categories were selected for co-occurrence analyses. The most important questions for university garden-based practitioners in the country are presented, related to actors involved, functions that gardens fulfill, strengths of these educational resources, and requirements for their consolidation.  相似文献   
67.
实验中使用国产2N级金属Gd粉为原料,用电弧熔炼法在氩气气氛中制备了Gd5Si1.8Ge22合金,并通过X射线衍射仪和超导量子磁强计分析手段对合金的性能进行测试和分析.发现合金没有重现一级磁相变和巨磁热效应,这是由于国产2N级Gd中杂质等因素时磁相变、磁热性能产生了重要影响,导致一级磁相变的破坏及磁热效应的大幅度下降.  相似文献   
68.
研究了对羧基苯偶氮硫代若丹宁 (CPATR)与汞的显色反应,在pH为3.5的醋酸-醋酸钠缓冲介质中,吐温-80存在下, CPATR与汞反应生成2:1稳定络合物,该络合物可被Waters Sep-Pak C18小柱固相萃取,用氮-氮二甲基甲酰胺(DMF)洗脱后用光度法测定,在洗脱液介质中,λmax=535 nm,体系摩尔吸光系数达8.70×103 m2/mol. 汞的质量浓度在0.05~4.0 mg/L内符合比尔定律. 该方法可用于烟草及其添加剂中汞含量的测定,结果满意.  相似文献   
69.
The person-centred review (PCR) is a model for the review of a student’s special educational needs (SEN) which places the young person and their family at the centre of the process. This mixed-methods, exploratory study investigated the views of 16 students with SEN aged between 10–11 years (Year 6) and 13–14 years (Year 9), and their parents/carers on their PCRs (which were mostly held at transition). Attention was paid to potential changes in the young people’s locus of control and feelings towards school. Findings indicated that the PCR is a collaborative, constructive and reassuring process for families where a wealth of information is shared openly and honestly within a relaxed, yet structured, meeting. The young people were generally positive about the process, although many felt daunted beforehand. Some parents felt the meeting was too long and not entirely accessible to children. The study did not conclude that the young people’s locus of control or feelings towards their education changed following the PCR. Implications for good practice are discussed, particularly for educational psychologists and in the context of the SEN and Disability Code of Practice.  相似文献   
70.
The goal of this work is to better understand the institutional changes in the educational systems of the Czech Republic, Hungary, Poland and Slovakia. We demonstrate that the educational reforms implemented during the transformation introduced very different institutional arrangements in the four countries, despite the fact that their systems shared many common characteristics at the beginning of the 1990s. Differences between the national approaches to educational reforms are particularly reflected in the modes of education decentralisation, the level of school autonomy, accountability and funding mechanisms. We believe that different institutional arrangements may have contributed to the divergent achievements of the Czech Republic, Slovakia, Hungary and Poland in the PISA programme.  相似文献   
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