Investigation on influencing factors of 5-HMF content in <Emphasis Type="Italic">Schisandra</Emphasis>   总被引：4，自引：0，他引：4  

Xu Q  Li YH  Lü XY 《Journal of Zhejiang University. Science. B》2007,8(6):439-445

In order to investigate the influencing factors of 5-hydroxymethyl-2-furaldehyde （5-HMF） content in Schisandra, confirm the theory of 5-HMF deriving mainly from Schisandra processing course, and give some suggestions about the Schisandra processing method, the 5-HMF contents in decoctions of Schisandra under different heating temperature, decocting time, soaking time, processing methods and treatment with different solvents before decocting the Schisandra were measured by RP-HPLC method. The results showed that there is great difference of 5-HMF level in decoctions from differently processed Schisandra and unprocessed Schisandra; decocting time of 60 rain has some effects on 5-HMF level in decoctions and there is certain quantity 5-HMF in processed Schisandra itself and very little 5-HMF in unprocessed Schisandra. Heating time, heating temperature and treating solvents all have effect on 5-HMF level in decoction of Schisandra. 5-HMF in Schisandra was mainly from processing course. Both long heating time and high heating temperature can increase 5-HMF level in Schisandra. The production of 5-HMF in Schisandra may have some relationships with some polar components, which can dissolve in water, ethanol and acetone, especially in ethanol. To control processing temperature, processing time and treatment with some solvent is very important for controlling 5-HMF level in Schisandra.  相似文献   

The role of intuition in pedagogical tact: Educator views     

Gerbert Sipman  Jürg Thölke  Rob Martens  Susan McKenney 《British Educational Research Journal》2019,45(6):1186-1202

Pedagogical tact concerns a teacher's ability to adequately handle complex classroom situations that require immediate action. As such, pedagogical tact can be viewed as an enactment of teachers’ intuition. While most teachers, teacher educators, educational leaders and scholars readily recognise the importance of pedagogical tact (and by extension, intuition), few pre-service or in-service programmes devote explicit attention to developing this important teacher quality. This study set out to understand why. Specifically, data were collected to investigate how educators perceive intuition, and its role in teacher pedagogical tact. Ten focus group discussions were held with school board members, teacher educators, school principals, in-service teachers and pre-service teachers. Participants recognised two types of intuition commonly described in the literature (local and nonlocal), and affirmed the importance of intuition for teacher pedagogical tact. These educators also noted that teachers are rarely if ever encouraged to make conscious use of their intuition, let alone develop it. There was consensus that teachers differ in how well they are able to tune into their intuition. Though the scale of the study is small, the findings suggest that more attention should be given to developing teacher intuition and pedagogical tact than is currently the case.  相似文献   

Lehrerbildung und Praxiserfahrung im ersten Berufsjahr und ihre Wirkung auf die Unterrichtskompetenzen von Studierenden und jungen Lehrpersonen im Berufseinstieg     

Prof. Dr. Matthias Baer MBA  Mirjam Kocher  Corinne Wyss  Titus Guldimann  Susanna Larcher  Günter Dörr 《Zeitschrift für Erziehungswissenschaft》2011,14(1):85-117

This contribution looks at the competency development during teacher training and entry into work. The multi-perspective research design makes it possible to collate data at five stages within this transition process: at the start (t₁), in the middle (t₂) and on completion (t₃) of teacher training for primary school level (year 1–6) student teachers in two education colleges in Switzerland, as well as novice teachers at the start (t₄) and on competition (t₅) of their first year of work. The data covers eleven topic areas. This paper will present findings of data analysis for two of these topic areas for all five stages of measurement: (a) knowledge of lesson planning was captured using case vignettes and (b) teaching practice during the study program and in the first year of work was recorded on video. The same data was collated from the teaching staff involved in the practical training of the student teachers. The statements on the case vignettes were studied using content-analysis. The lesson videos were analyzed using low-inference coding for the visible occurrences during teaching and with a high-inference rating on the quality of the lessons. The results, including those for a comparison of student teachers and novice teachers with practical teacher training staff, give insights into the effectiveness of teacher training and the impact of practical experience in the first year of work on knowledge of how to plan lessons and on the form and quality of teaching. Overall, the new training at both education colleges can be given a pleasingly positive appraisal in terms of professionalization. It is, however, also possible to recognize where and to what extent a need for further developing the standard of professionalization of teaching still exists.  相似文献   

Beitr?ge aus der aktuellen Herbartianismusforschung zwischen ?Zukunft“ und ?Reformp?dagogik“     

Steffen Schlüter 《Zeitschrift für Erziehungswissenschaft》2011,14(4):691-700

  相似文献   

School improvement through inspections? First empirical insights from Germany   总被引：1，自引：0，他引：1  

Kathrin Dedering  Sabine Müller 《Journal of Educational Change》2011,12(3):301-322

Since the late 1990s, broad discussions on education and educational quality have given impetus to the implementation of many new measures aimed at the improvement of schools in Germany. In this context, school inspections have been introduced in all 16 German federal states during the last 6 years. In the meantime, scientific research into the functioning of this steering instrument has begun. In this article, first empirical findings on the effects of school inspections in Germany are presented by drawing on a survey study with 468 principals of schools in the federal state of North Rhine-Westphalia that were externally evaluated during the years 2005 to 2008. Findings indicate that school inspection results are considered by a large group of stakeholders within schools and that they are discussed in different settings. In many schools, development measures have already been planned and implemented. Moreover, first effects are perceived in different fields. On the whole, findings agree with the results of two thematically related German studies but draw a less heterogeneous picture than the international research context.  相似文献   

大学生课余生活状况调查   总被引：1，自引：0，他引：1  

张媛  吕英喆  阎占定 《高校辅导员学刊》2011,3(6):83-87

对大学生课余生活学习状况的研究,不仅有利于了解大学生这个群体的生活状况,也有助于搞好大学生的日常管理和思想政治教育工作。本文通过问卷调查、访谈、座谈等调查方式,对20多所高校大学生消费状况、学习生活和情感生活进行了调查分析,从而为大学生健康生活方式的培养提供了参考依据。  相似文献   

煤中添加 NH4 Br 对气相汞氧化脱除及脱硝的实验研究     

赵士林  段钰锋  周强  朱纯  佘敏  吕剑虹 《东南大学学报》2015,(2)

为脱除烟气中的气相汞和 NOx,进行了贵州无烟煤中添加 NH4 Br 对烟气汞氧化脱除协同脱硝的实验研究．在热重分析仪上研究添加 NH4 Br 对着火温度和燃烧特性的影响．在6 kW 流化床燃烧（FBC）试验装置上研究了在煤中不同 NH4 Br 添加量对气相汞氧化脱除的影响．采用安大略法（OHM）对烟气中汞形态浓度进行了测定并得出汞质量平衡．结果表明,添加 NH4 Br 对贵州无烟煤的着火温度没有影响．原煤燃烧汞质量平衡率为95．47％,颗粒汞 Hgp、气态 Hg0和 Hg2＋比例分别为75．28％,11．60％,13．12％．由于飞灰中含有较高的未燃尽碳,烟气中 Hgp 浓度较高．随着 NH4 Br 添加量从0增加至0．3％,烟气中气态 Hg0和 Hg2＋减少,Hgp 相应增加．Hg0的氧化率与煤中 Br 的添加量成正相关．这表明煤燃烧中添加 NH4 Br 可促进 Hg0的氧化和脱除．烟气中 NOx 随着 NH4 Br 的添加呈减小趋势,其脱除率在0．3％添加量时达最大（17．31％）．添加 NH4 Br 同时具有协同脱硝的作用．  相似文献   

CFD Simulation of Film Flow and Gas/Liquid Countercurrent Flow on Structured Packing     

高国华  张吕鸿  李鑫钢  隋红 《天津大学学报(英文版)》2011,17(3):194-198

A mathematic model of two-phase flow and a physical model of two-dimensional (2D) vertical section for the plate-type structured packing Mellapak 250.Y were set up and verified. The models were used to study the influence of packing’s surface microstructure on the continuity of liquid film and the amount of liquid holdup. Simulation results show that the round corner shape and micro wavy structure are favorable in remaining the continuity of liquid film and increasing the amount of liquid holdup. The appropriate liquid flow rate was determined by investigating different liquid loadings to obtain an unbroken liquid film on the packing surface. The pressure difference between inlet and outlet for gas phase allowed gas and liquid to flow countercurrently in a 2D computational domain. The direction change of gas flow occurred near the phase interface area.  相似文献   

Studienabbruch und -wechsel in den neuen Bachelorstudiengängen     

Irmela Blüthmann  Steffen Lepa  Felicitas Thiel 《Zeitschrift für Erziehungswissenschaft》2008,11(3):406-429

The article gives an overview of current state of research concerning study drop-out. Then, on basis of successfully validated scales from literature, a new instrument for measuring personal reasons for abandoning bachelor study programs is developed and tested for reliability and validity. A study drop-out, based on study conditions and study demands, will be tested by a path model.  相似文献   

Environmental education in a ‘green classroom’     

Jürgen Drissner  Hans-Martin Haase  Mara Nikolajek  Katrin Hille 《Resonance》2011,16(2):180-187

The ‘Green Classroom’ in the Botanical Garden of Ulm is an experiential learning forum outside school. Its educational concept is based on experimental learning and is geared towards expanding biological knowledge and developing positive attitudes towards small animals such as invertebrates and insects. The attitudes of 68 school students towards small animals, before and after they visited the ‘Green Classroom’, were assessed and the answers they gave in their questionnaires were compared with those of 60 students froma control group that was not yet exposed to this learning environment. Although the students spent only one morning in the ‘Green Classroom’, some of their attitudes towards small animals improved after their visit. These studies underscore the necessity for direct observation and familiarization of the environment including small animals such as invertebrates and insects for appreciating issues related to biodiversity and conservation.  相似文献