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1.
J Heyrovsky’s invention of polarography in which a dropping mercury electrode is used in the electrochemical cell revolutionised
electroanalysis, study of electrode kinetics and adsorption studies on mercury electrodes. Polarography has also directly
contributed to the development of new and innovative ideas in electrochemical techniques, instrumentation and applications 相似文献
2.
1 Introduction Molten salts are considered to be used as fluid tar-gets in the nuclear incineration of transuranic elementswith proto accelerators .The molten salts are also usedas the media in high temperature chemical reprocess-ing of spent nuclear fuel of fast reactors .The phase di-agrams of rare earth metal halides in combination withalkali metal halide systems are of pri me i mportance inapplication. The thermodynamic properties and phase diagramsof the DyCl3-MClnsystems ( M =alkali or… 相似文献
3.
杨媚 《新乡师范高等专科学校学报》2002,16(4):109-110
音乐教育是高校素质教育的重要组成部分 ,它不仅是未来基础师资素质构成的重要组成部分 ,而且也是激发学生潜在创造力的有力手段。但我国目前高校音乐教育的现状却不容乐观 ,我们要转变观念 ,大力加强高校音乐教育 ,使音乐教育在提高大学生人文素质方面发挥自己的独特优势和更大的作用 相似文献
4.
Shyh-ming Lin 《Environmental Education Research》2016,22(5):658-682
This study applied environmental behavioural theories to develop a personal carbon footprint management system and used persuasive technology to implement it. The system serves as an educational system to improve the determinants of students’ low-carbon behaviours, to promote low-carbon concepts and to facilitate their carbon management. To assess the validity of the system, high school students were chosen to participate in an experiment, the results of which reveal (1) the system has significant and positive short-term and relatively long-term effects on the reduction of their self-reported carbon footprint, (2) the system significantly improves their carbon footprint awareness and perceived behavioural control (PBC), and it also promotes behavioural subjective norms, (3) reduction of their self-reported carbon footprint is significantly correlated to PBC, carbon footprint awareness and attitude and (4) PBC is the most critical determinant of carbon reduction. Suggestions are accordingly made. 相似文献
5.
运用电化学理论解决了中学化学教学中的一系列疑难问题,阐述了电化学在中学化学教学中的指导作用。 相似文献
6.
Hsiang-Ting Chen Hsin-Hui Wang Ying-Yan Lu Huann-shyang Lin 《International Journal of Science Education》2016,38(2):170-191
This study explored the effects of a modified argument-driven inquiry approach on Grade 4 students’ engagement in learning science and argumentation in Taiwan. The students were recruited as an experimental group (EG, n?=?36) to join a 12-week study, while another 36 Grade 4 students from the same schools were randomly selected to be the comparison group (CG). All participants completed a questionnaire at the beginning and end of this study. In addition, four target students with the highest and the other four students with the lowest pretest engagement in learning science or argumentation to be observed weekly and interviewed following the posttest. Initial results revealed that the EG students’ total engagement in learning science and argumentation and the claim and warrant components were significantly higher than the CG students. In addition, the EG students’ anxiety in learning science significantly decreased during the study; and their posttest total engagement in learning science scores were positively associated with their argumentation scores. Interview and observation results were consistent with the quantitative findings. Instructional implications and research recommendations are discussed. 相似文献
7.
用甲基纤维素(MC)将过氧化氢酶(Cat)固载于热裂解石墨电极表面,制备了Cat-MC膜修饰电极.甲基纤维素膜中的过氧化氢酶与电极直接传递电子.在pH6.0的磷酸盐缓冲溶液中可得到一对可逆的过氧化氢酶辅基血红素Fe(III)/Fe(II)电对氧化还原峰,式电势为-0.331V(vsSCE).其式电势随溶液的pH值增加而负移且成线性关系,直线斜率为-38.0mV/pH,说明过氧化氢酶的电子传递过程伴随有质子的转移.并研究了过氧化氢酶修饰电极对H2O2的电催化性能.在H2O2一定浓度范围(15.6~110.1μmol/L)内,催化电流与H2O2浓度成线性关系. 相似文献
8.
在pH=9.0 H3BO3-Na2B4O7缓冲体系中,以5-溴水杨醛甘氨酸修饰碳糊电极为工作电极,Cu2 于 120mV(vs.SCE)处产生一灵敏的吸附波,其二阶导数峰电流与Cu2 浓度在4.0×10-9~8.0×10-7mol.dm-3范围内呈良好的线性关系,相关系数为0.9964,检出限为6.0×10-10mol.dm-3(3倍信噪比)。应用该法测定发样中Cu2 的含量,结果令人满意。 相似文献
9.
10.
介绍了用纳米碳-PVC膜修饰电极测定痕量镉的新方法。优化了各种试验条件,如支持电解质的选择、pH值的影响、修饰剂的用量、富集电位及时间、扫描速率等。 相似文献