4.1删除和恢复 本节主要介绍如何对图纸中的没用的实体进行删除,以及如何恢复 错误删除的实体。下面将分别介绍“删除”(Erase)和“恢复”(Oops )命令的使用方法和具体的操作作过程

7-1 Introduction to the Activated-Sludge Process Historical Development Experiments conducted at the Lawrence Experiment Station during 1912 and 1913 by Clark and Gage With air input into wastewater, growths of organisms could be cultivated in bottles and in tanks partially filled with roofing slate spaced about 25 mm (1 in) apart and would greatly increase the degree of purification

Treatment methods in which the application of physical forces predominate are known as physical unit operations. Examples of physical unit operations include screening, mixing, sedimentation, gas transfer, filtration, and adsorption. Treatment methods in which the removal or conversion of constituents is brought about by the addition

Every community produces both liquid and solid wastes and air emissions. The liquid waste-wastewater is essentially the water supply of the community after it has been used in a variety of applications. From the standpoint of sources of generation, wastewater may be defined as a combination of the liquid or water-carried wastes removed from residences. institutions and commercial and industrial establishments together with such groundwater

Operations used for the treatment of wastewater in which change is brought about by means of or through the application of physical forces are known as physical unit operations. Because physical unit operations were derived originally from observations of the physical world. they were the first treatment methods to be used. Today, physical unit operations, as shown on Fig. 5-1, are a major part of most wastewater

The constituents of concern found in wastewater are removed by physical, chemical, and biological methods. The individual methods usually are classified as physical unit operations, chemical unit processes, and biological unit ds in which the application of physical forces ohysical unit operations include pr T3clarifiers

一、固体废物的定义 固体废物（solid wastes）亦称废物，是指人类在生产、加工、流通、消费以及生活等过 程中提取所需目的成分之后，所丢弃的固态或泥浆状的物质。 随着人类社会文明的发展，人们在索取和利用自然资源从事生产和生活活动时，由于客观 条件的限制，总要把其中的一部分作为废物丢弃。另外，由于各种产品本身也有其使用寿命， 超过了寿命期限，也会成为废物

第一节 管流系统的衡算方程 第二节 流体流动的内摩擦力 第三节 边界层理论 第四节 流体流动的阻力损失 第五节 管路计算 第六节 流体测量

第一节 常用物理量 常用物理量及单位换算 常用物理量及其表示方法 第二节 质量衡算 衡算系统的概念 总质量衡算方程 第三节 能量衡算 总能量衡算方程 热量衡算方程

Determining wastewater flowrates and constituent mass loadings is a fundamental step in initiating the conceptual process design of wastewater treatment facilities. Reliable data for existing and projected flowrates affect the hydraulic characteristics, sizing, and operational considerations of the treatment system components. Constituent mass loading, the product of constituent concentration and flowrate