The C—X bond of alkyl halides is polarized. The carbon atom bears a partial positive charge, The halogen atom a partial negative charge

一、了解图形系统的框架及其涉及的软件、硬件技术； 二、了解图形学的基本问题，掌握图形学的基本概念、方法与算法； 三、 对与图形相关的应用及当前的研究热点有一个初步认识； 四、具有一定实践体会和相关的编程能力

The different arrangements of atoms caused by rotation about a single bond are called conformations (构象)of the molecule, and a specific conformation is called a conformer (构象异构体, conformation isomer). An analysis of the energy changes that a molecule undergoes as groups rotate about single bonds is called a conformational analysis (构象分析)

社会历史发展到今天，其管理模式也发生了根本性的变化，即由“统治”（government）到“治理”(governance)的转变。政府统治的权力运行方向是自上而下的，它运用政府的政治权力，通过发号施令，对社会公共事务实行单向度的管理。与此相反，治理则是一个上下互动的管理过程，它主要通过合作、协商、伙伴关系、确立认同和共同目标等方式来实现对社会公共事务的管理，所以治理的权力向度是多元的、相互的。这种“治理”就是公民社会的自治

The primary source of alkanes is petroleum Natural gas consists chiefly of methane, but ethane, propane, butane, and isobutane are also present. Petroleum is a complex mixture of hydrocarbons that must be refined into different fraction before it can be used

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

Phenols are like alcohols in being able to form strong intermolecular hydrogen bonds. Phenols have higher boiling points than hydrocarbons of the same molecular weight. A modest solubility in water

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

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

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