发现一些薄层分析法更复杂的技巧---剪玻璃TLC板,用火 焰造TLC染色剂点棍,使用TLC染色剂以使点显像。 Discover a few of the more complicatec skills related to thin layer chromatography cutting glass TLC plates, flame-pulling spotters, and using TLC stains to visualize spots

在本影片中学习如何熟悉滴定技术---用酚?在酸/碱滴定中的详 细示范。 Learn how to master the art of titration in this video-with a detailed demonstration of an acid/base titration using phenolphthalein

described in these materials are potentially hazardous and require a high lcvel ofsafity training special facilitics and equipment, and supavision by approprinte duals. You bear the sol responsiblity, liability, and risk for the impkemcntation of such safety procedures and measures. MiT shall have no responsibility, liability, ar risk for the content ar implem of ay of the matcrial presented. Legal Notices

Chemists use spectroscopy (Ir, UV-Vis, NMR) to determine molecular structure. spectroscopy: technique that measures the amount of radiation a substance absorbs at various wavelengths(based on the quantization of molecular energy levels Molecules exist in quantized energy states (rotational, vibrational, and electronic quantum states) Molecules absorb discrete amounts of energy(ae)and are excited to higher

equipment and supavision by appropriate individuak You bear the sol responsibility, liability, and risk for the implemcntation of such safety procedures a ares. MIT shall have no responsibility, liability, risk for the content or implementation of of the mat

WARNING NOTICE: The erperimants descnbed in these materials are potentially hao ardous and require a high level ofsafcty training special facilitics and equipment, and supervision by approprinte individuals. You bear the solc responsibility, liability, and risak for the implemcntation of such safdty procedunes and measures. MrT shall have no responsiblity, liability, risk for the content or implemcutation of amy of the matcrial presented. Legal Notices

1. 掌握化学反应速率的表示方法、反应级数和反应分子数的概念； 2. 掌握具有简单级数反应的动力学特征，掌握从实验数据确定此类反应的级数、反应速率常数和其它有关计算；

1、了解电磁波谱与分子吸收光谱的关系; 2、掌握红外光谱、核磁共振谱的基本原理和应用; 3、了解紫外光谱和质谱的基本原理和应用; 4、掌握紫外光谱、红外光谱、核磁共振谱与分子结构的关系;

采用电弧喷涂法制备Zn-Al-Mg-La-Ce涂层,通过盐雾试验对涂层进行腐蚀,利用能谱分析、X射线衍射分析、扫描电镜观察、极化曲线以及电化学阻抗谱等手段对腐蚀前后的Zn-Al-Mg-La-Ce涂层进行了研究.结果表明:实验制备的Zn-Al-Mg-La-Ce涂层具有较好的自封闭效果,组织致密,在腐蚀过程中表面的微观孔隙能够被自身的腐蚀产物有效堵塞,涂层表面形成的致密腐蚀产物层能够阻止腐蚀的进一步发生.因此,Zn-Al-Mg-La-Ce涂层具有优异的耐蚀性能

本文研究了一种新型的高硬度(HRC>58),高韧性(ak ≥ 40J/cm2)的结构钢的化学成分及热处理对冲击韧性的影响,实验结果表明,微量钙对改善钢在淬火-低温回火态的冲击韧性有重要作用,铬含量及铜/硅比对冲击韧性也有一定的影响