An acid is a substance that can donate (or lose) a proton, A base is a substance that can accept (or remove) a proton

Functional groups The structural features that make it possible to classify compounds by reactivity are called functional groups. A functional group is a part of a larger molecule and is composed of an atom or a group of atoms that have a characteristic chemical behavior. The Chemistry of every organic molecules

Quinones are an interesting and valuable class of compounds because of their oxidation-reduction, or redox, properties. The redox properties of quinones are important to the functioning of living cells, where compounds called ubiquinones(泛醌) act as biochemical oxidizing agents to mediate the electro-transfer processes involved in energy production

Aldehydes are named by replacing the terminal –e of the corresponding alkane name with –al. The longest chain selected as the base name must contain the –CHO group, and the –CHO carbon is always numbered as carbon 1

17.1 The Acidity of the α Hydrogens of Carbonyl Compounds: Enolate Anions 17.2 Keto and Enol Tautomers 17.3 Reactions via Enols and Enolate Anions

More reactive than benzene toward electrophilic substitution NO2 An deactivating group Less reactive than benzene toward electrophilic substitution Ortho-para director Meta director

The most characteristic reactions of benzenoid arenes are the substitution reactions that occur when they react with electrophilic reagents. The electrophiles are either a positive ion (E+) or some other electron-deficient species with a large partial positive charge

1.广域网的通信线路与接入技术 2.包交换机与路由器工作原理 3.再谈网络的灵魂,网络的语言——协议(实现异构网络的连接)

三、分组交换与路由 1.广域网的结构 2.编址与分组交换 3.路由问题 4.常用广域网

1.不同类型的局域网,不同的用途Ethernet; FDDI; ATM; 无线网 2.不同类型的局域网,异构的;如何连接? 3.如何构造Ethernet局域网?总线式集线器 交换式集线器; 4.Ethernet的工作原理(CSMA/CD)组建后的局域网,如何应用?