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921.
922.
We describe the results of electromigration desalination of two soluble salt-contaminated Galician granites. The efficacy of electromigration, which had not been previously applied to granite, was assessed for two types of granite contaminated with a 20% NaCl solution and seawater. Desalination effectiveness was evaluated as follows: (1) analysis of anode and cathode ion content during testing; (2) analysis of ions at different distances from the electrodes after testing; (3) pH assessment of the stone surfaces; and (4) evaluation of colour changes. Results were very satisfactory; by the end of testing, chloride was reduced by almost 100% in both the NaCl and seawater contaminated samples. Sulfate reduction was also significant, despite this ion's lower mobility. The granite pH values remained close to neutral and colour changes were minimal. The difference in effectiveness of the process for the two types of stone was associated with their dissimilar pore structure.  相似文献   
923.
MBA education has become the fastest growing segment of education in China in recent years and a segment that can now be considered indispensible. However, how best to teach it has long been a source of debate. One of the key issues is how to match student traits with teaching methods. While engaged as teachers of marketing management, the authors collected data by questionnaire, carried out empirical research and data comparison, and undertook contingency analysis. It was found that different personal traits in students lead to different attitudes towards teaching methods. A student’s major in college, gender, and sector of employment has little influence on attitudes towards teaching methods, while age, the most sensitive factor, plays the biggest role, followed by job and class. Therefore, these factors should be taken into consideration when arranging classes, developing the curriculum, and planning teaching methods.  相似文献   
924.
This essay considers the question of why we should teach science to K-2. After initial consideration of two traditional reasons for studying science, six assertions supporting the idea that even small children should be exposed to science are given. These are, in order: (1) Children naturally enjoy observing and thinking about nature. (2) Exposing students to science develops positive attitudes towards science. (3) Early exposure to scientific phenomena leads to better understanding of the scientific concepts studied later in a formal way. (4) The use of scientifically informed language at an early age influences the eventual development of scientific concepts. (5) Children can understand scientific concepts and reason scientifically. (6) Science is an efficient means for developing scientific thinking. Concrete illustrations of some of the ideas discussed in this essay, particularly, how language and prior knowledge may influence the development of scientific concepts, are then provided. The essay concludes by emphasizing that there is a window of opportunity that educators should exploit by presenting science as part of the curriculum in both kindergarten and the first years of primary school.  相似文献   
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Editorial     
Rajaram Nityananda 《Resonance》2017,22(12):1103-1104
  相似文献   
930.
Editorial     
B. Sury 《Resonance》2017,22(5):431-432
  相似文献   
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