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材料化学是材料学与化学等学科交叉、渗透下产生的一门新兴交叉学科,其学科内容还没有得到一致的认同,对应材料化学课程的内容往往与材料化学专业开设的其他课程内容出现重叠.本文通过对材料化学专业要求、核心知识领域以及材料化学学科概念的分析,对材料化学课程内容和材料化学专业课程体系的设置作了初步的探讨. 相似文献
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培养发展型教师的化学教学论课程改革 总被引:6,自引:0,他引:6
从课程目标、课程内容、教学方法和课程评价 4个方面论述了培养发展型教师的化学教学论课程的改革 ,提出了一些观点及可操作的实施方法 相似文献
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就化学教师怎样开发开设高质量、有化学学科特色的校本课程,从4个方面进行了实践探索:预设课程目标、精选课程内容,活用教学方法、积极展开评价,并结合具体案例“走进化学科学发展史”进行了阐述。 相似文献
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半导体材料硅,在第三周期IVA族,核外有4个电子,具有较稳定的结构。简述了硅的发展应用史;从化学角度,对单质硅材料、二氧化硅材料、有机硅材料等几个典型材料的元素结构、制备工艺、反应机理和应用机理等方面进行详细分析;总结展望了硅元素未来的发展。 相似文献
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我国近30年来,特别是近10年来的基础化学教育课程和教学改革所取得的成果十分丰硕。本文从5个方面进行总括和述评:)1)适应科学教育发展的需求,变革化学课程结构与组织形态;)2)重新建构课程内容体系,实现化学教材编制的多样化;)3)革新化学课程内容的呈现方式,促进学生有效学习;)4)强化评价的激励作用,实行全面性的化学课程评价体制;)5)培养专业化的教师队伍,促进化学教师教育的发展。 相似文献
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以PCK发展为切入点对“化学教学技能训练”课程进行系统的课程设计。该课程设计结合我国教师教育课程设置的现状,利用PCK与化学教学技能的内在联系,强调课程目标确定、课程内容选择、课程内容组织等方面的整体优化设计,实现PCK与化学教学技能双促进的学习效果。 相似文献
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新型无机材料中的化学 总被引:1,自引:0,他引:1
在几千年社会文明的发展过程中 ,材料一直是人类赖以生活和生产的物质基础。现代社会中 ,材料的重要作用变得更加突出。从 2 0世纪末开始 ,材料科学的发展突飞猛进 ,新材料和新工艺不断涌现 ,这在很大程度上改变了社会的面貌。化学在材料科学中的作用主要表现在两个方面 :首先 ,化学肩负着发现新分子、新结构和新材料的任务。化学家是第一个看到新分子和新材料的人 ,因此化学家在材料研究中处于近水楼台先得月的有利地位。其次 ,材料性能的优化、材料的改性和材料的制备工艺都以化学过程为基础。到目前为止这部分工作仍主要以实验和经验为基… 相似文献
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摩擦化学的主要研究领域及其发展趋势 总被引:35,自引:0,他引:35
本文从摩擦过程中表面产生的化学效应、干摩擦及油润滑状态下的摩擦化学三个方面评述了摩擦化学的研究内容和进展; 介绍了摩擦化学在材料制备中的应用及摩擦化学的研究方法; 对摩擦化学研究中存在的问题及其发展趋势进行了讨论。 相似文献
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Hanna Kowalska Jolanta Kowalska Anna Ignaczak Ewelina Masiarz Ewa Domian Sabina Galus Agnieszka Ciurzyska Agnieszka Salamon Agnieszka Zajc Agata Marzec 《Molecules (Basel, Switzerland)》2021,26(13)
The aim of this study was to find the effect of kale and dietary fibre (DF) on the physicochemical properties, nutritional value and sensory quality of multigrain bars. A recipe of multigrain bars was prepared with the addition of fresh kale (20% and 30%) and DF preparations (apple, blackcurrant, chokeberry and hibiscus). The bars were baked at 180 °C for 20 min. These snack bars, based on pumpkin seeds, sunflower seeds, flaxseed and wholegrain oatmeal, are a high-calorie product (302–367 kcal/100 g). However, the composition of the bars encourages consumption. In addition to the ability to quickly satisfy hunger, such bars are rich in many natural ingredients that are considered pro-health (high fibre content (9.1–11.6 g/100 g), protein (11.2–14.3 g/100 g), fat (17.0–21.1 g/100 g, including unsaturated fatty acids), carbohydrates (20.5–24.0 g/100 g), as well as vitamins, minerals and a large number of substances from the antioxidant group. The addition of kale caused a significant increase of water content, but reduction in the value of all texture parameters (TPA profiles) as well as calorific values. The content of polyphenols was strongly and positively correlated with the antioxidant activity (r = 0.92). In the bars with 30% addition of kale (422 mg GA/100 g d.m.), the content of polyphenols was significantly higher than based ones (334 mg GA/100 g d.m.). Bars with the addition of the DF were characterized by a higher antioxidant activity, and the content of carotenoids, chlorophyll A and B and polyphenols. High sensory quality was demonstrated for all (from 4.8 to 7.1 on a 10-point scale). The addition of fibre preparations was also related to technological aspects and allows to create attractive bars without additional chemicals. 相似文献
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“化学反应速率”综合体现了微粒观、实验观及科学本质观等化学基本观念,是提高学生科学素养的重要载体。从内容选取、内容编排与内容呈现3个方面对英国索尔特高级化学课程教材与国内化学教材中“化学反应速率”相关内容的编写进行比较,并简要阐述几点对化学教材编写和化学教学的启示。 相似文献
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The present study was designed to evaluate the contents of different antioxidants compounds and their antioxidant activities in Jalopeno peppers (Capsicum annuum) cultivars (El Dorido, Grande, Tula, Sayula and El Rey) extracts. Free radical scavenging activity of Grande was recorded as high as 87% followed by El Dorido (83%). Results of reducing power (Fe3+ to Fe2+) showed that Grande (0.85%) and El Dorido (0.81%) fruit extract absorbance value were close to synthetic antioxidant BHT (0. 97%) obtained at100 μg/mL. The results showed that total phenolic content of El Dorido and Grande were significantly higher compared to other Jalapeno pepper. Results indicated strong and positive correlation between antioxidant activity and carotenoids content (r = 0.75), vitamin C (r = 0.78) and total capsaicinoids (r = 0.84), respectively. The results of the antioxidant activity assays showed that the El Dorido and Grande had strongest antioxidant activity compared to other peppers cultivars in this study. 相似文献
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The methylation of humic acids (HA) with dimethylsulfate in acetone and methanol followed by the iodometric determination of the methoxy groups (Zeisel reaction) were applied to determine the contents of –OH groups in solid samples of HA of different origins. For the coal- and peat-derived HA samples, the contents of –OH groups determined after methylation in acetone ranged from 6.6 to 8.7 mmol/g, whereas the contents of –OH groups determined after methylation in methanol ranged from 4.0 to 5.0 mmol/g. These differences may be related to the content of carboxylic groups in the HA molecule that were not methylated in methanol, as confirmed by a comparison with results of conventional titrimetric determinations. Observed differences were interpreted as results of different polarity of both solvents and alkalinity of the reaction mixture during the methylation. The contents of alcoholic groups as well as some other minor –OH groups can be estimated using the –OH group contents obtained after methylation in both solvents together with the results of the conventional determinations of acidic functional groups. A repeatability of the –OH groups determination as estimated from a series of triplicate analyses of different HA samples (n = 7) was in range of 0.15–0.73 mmol/g and 0.08–1.06 mmol/g (standard deviations) for methylation in acetone and methanol, respectively. Thus, the average repeatability of the –OH groups determination was estimated to be 0.38 and 0.50 mmol/g for methylation in acetone and methanol, respectively. 相似文献
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Fatih Karahan Muhittin Kulak Emrah Urlu Hediye Gül Gözüacik Tülay Böyümez 《Natural product research》2015,29(17):1678-1683
Arum dioscoridis, locally called ‘Gavur pancari’, is a wild plant the leaves of which have been used as vegetable and for preparing special soup which has a sour taste. This study was set up to determine in vitro antioxidant activities and total phenolic and flavonoid contents of different extracts of A. dioscoridis. Free radical scavenging activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing activity with different concentrations of ethanol, methanol, acetone and water extracts of the plant leaves. Total phenolic and flavonoid contents were widely variable depending on solvents. Ethanol and methanol extractions of the plant material showed better performances with respect to both phenolic and flavonoid contents, respectively. The highest phenolic and flavonoid contents of ethanol and methanol extracts were 100.890 mg/g GAE and 72.643 mg/g QE, respectively. The lower DPPH scavenging and ferric reducing activities were determined in comparison with previous reports and standard synthetic chemicals. 相似文献