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1、一、教学目的及要求： 使学生了解和掌握元素和化合物的部分词汇及其构成，理解课文内容和翻译。理解专业英语的学习方法、教学要求和成绩考查方法。二、教学内容提要：学习lesson one Text A Element and CompoundsAll matter is composed of basic substances called element. An element cannot be broken down into simpler units by chemical reactions; it contains only one kinds of atom. An atom is
2、the smallest characteristic unit of an element.A compound is a substance that can be spit into two or more element. Water is a compound because it can be spit into its components, hydrogen and oxygen. The formula of a compound gives information about the kinds and numbers of atoms that make up each
3、molecule of that compound. A formula contains the symbols of the kinds of atoms in each molecule and subscripts that indicate the number of each kinds of atom in the molecule. For example, the formula for waterH2Oindicate that a water molecule contains two hydrogen atoms and one oxygen atom; and a m
4、olecule of the glucose, C6H12O6, contains six carbon atoms, twelve hydrogen atoms, and six oxygen atoms.When carbon unites with oxygen, it forms a colorless, odorless, and tasteless gas called carbon dioxide, which is heavier than air and will extinguish flame.Carbon dioxide is like nitrogen in many
5、 ways, but if it is mixed with limewater, it causes the clear liquid to become milky, while nitrogen does not. This is the test for carbon dioxide.Carbon dioxide is a source of plant food. Plants have the power to take this gas from the air, combine it with water, and make it into their tissues; in
6、fact it is from this source that all organic carbon comes.Mineral compounds are made of elements such as sulphur, phosphorus, iron, potassium, sodium, and calcium. Calcium unites with sulphur and oxygen to form calcium sulphate, and with phosphorus and oxygen to form calcium phosphate.学习lesson one T
7、ext B carbohydrates Carbohydrates are usually defined as polyhydroxy aldehydes and ketones or substances that hydrolyze to yield polyhydroxy aldehydes and ketones.Monosaccharides are classified according to (1)the number of carbon atoms present in the molecule and (2)whether they contain an aldehyde
8、 or keto group, thus a monosaccharide containing six carbon atoms is called hexose; a monosaccharide containing an aldehyde group is called an aldose; and one containing a keto is called a ketose.The most important representatives of monosaccharides are glucose, arabinose, glactose, mannose, ribose,
9、 and fructose. Glucose is usually used as a carbon source for fermentation. Because the glucose in refined form such as crystalline form or as syrup form is more expensive, glucose in fermentation medium is mostly produced by direct enzymatic conversion of starch.The oligosaccharides can be classifi
10、ed into disaccharides and trisaccharides. The most important representatives of disaccharides are sucrose (from beet or cane), lactose, maltose and cellobiose . the most important representative of trisaccharide is raffinose which occurs in sugar beet.Sucrose is available for use in fermentation pro
11、cess either in crystalline form or in crude form as raw juice or molasses (a by-product of sugar manufacture). The sucrose contained in molasses is obviously cheaper, but the compositions of molasses varies greatly with source(cane or beet),quality of the crop and the nature of the sugar refining pr
12、ocess. The molasses should be pretreated before being used as a raw material for fermentation medium.Lactose is present in whey (a by-product of cheese making that arise following the separation of curds, the solidified casein and butter fat) at a concentration of 4%5% and whole whey or deproteinize
13、d whey is used as a cheap source of carbohydrate in some alcohol production process.Polysaccharides are constructed from monosaccharide unit and their derivatives, and have ten to several thousand units. D-glucose is the most common unit. They are insoluble and nonreducing. The most important repres
14、entatives are starch, glycogens, and cellulose.Starch is the most important carbohydrate used in fermentation process. It is from plants such as corn, rice, wheat, potatoes and cassava.The extent of starch hydrolysis required varies with fermentation process and depends on considerations as to wheth
15、er or not the microbial strain to be used produces amylase and whether product synthesis is subject to catabolite repression. For citric acid production, because the A. niger has the ability to synthesize glucoamylase (or amyloglucosidase: an enzyme that catalyzes the removal of one glucose molecule
16、 at a time from the terminal end of dextrins, breaking 1,4 links), the starch slurry is gelatinized by cooking at high temperature, then the gelatinized starch is liquefied and dextrinized by thermo-stable amylase, and the saccharification step is not necessary. The soluble dextrin hydrolysate is used as raw material for fermentation medium.学习：Reading Materials: Medium Design三、教学重点、难点及处理方法： 学生开始接触专业英语，会感觉有太多的英语词汇不认识。通过教学可以提前使初步学生了解英语科技文章的特点。
