18.1 Paper is made of cellulose fibers Paper was first made HARDWOOD FIBERS in China as early as AD 100, of mulberry bark, and then introduced to Western world by Arabs in eighth century. The first paper mills were built in spain in 11th century

一、物质波(materials waves) 法国物理学家德布罗意(Louis Victor de Broglie 1892-1987) 思想方法自然界在许多方 面都是明显地对称的,他采用类 比的方法提出物质波的假设

dscnibed in these materials are potentially hazardous and require a high level ofsafcty training special facilitics and equ by approp lividuak You bear the sole responsibility, liability, and risk for the in plementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of amy of the matcrial presented. Legal Notices

1—1.材料力学的任务(Basic Task of Mechanics of Materials) 1—2.材料力学与生产实践的关系 1—3.可变形固体的性质及其基本假设 Deformable Solids and their Basic Hypotheses 1—4.材料力学主要研究对象(杆件)的几何特征

1.1 The Definition of Metabolism The highly integrated network of chemical transformations. Degradation (decreasing order, thus energy releasing) to provide energy, catabolism; Synthesis (increasing order, thus energy consuming) to provide building materials, anabolism

ERP的基本概念基础数据 物料清单(Bill of Materials,BOM) 一产品结构的技术性描述文件; 呈树型结构,又可被称为产品树; 记录产品组件、子件、零件和原材料之间的结构关系,以及每个组装件所需要的各下属部件的数量;

Genetic Engineering and Biotechnology Genetic engineering: Isolation manipulation and expression of genetic materials. Gene cloning: Isolation and purification of specific genes In vitro recombination=recombinant DNA

1、复合材料的定义 什么是复合材料(Composition Materials, Composite)? 要给复合材料下一个严格精确而又统一的定义是很困难的。概括前人的观点,有关复合材料的定义或偏重于考虑复合后材料的性能,或偏重于考虑复合材料的结构

The food manufacturing industry, in general, has always been a highly competitive business but no branch of it is more so than dehydration. Profitability hinges on so many factors, some of which are outside the manufacturer's control. One of the main hazards in this context is that of climate. Total solids in raw materials are the key to a viable operation, and, if these are low, due to wet growing conditions, the plant throughput is going to be seriously reduced

The location of the dehydration factory must be considered very carefully, because, whereas at one time proximity to the source of raw materials was of paramount importance, availability of an adequate labour force and the provision for effluent disposal will, perhaps, constitute a more pressing requirement. A rural environment is obviously better than a location in a highly industrialised area, because the operation involves the utilisation of a considerable amount