在实际绘图时,可能需要放大或缩小视图的显示比例。对视图进行 缩放不会改变对象的绝对大小,它只是更改了视图的显示比例。启 动视图缩放命令的方法如下:

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

Volatile organic compounds (VOCs) are liquids or solids that contain organic carbon (carbon bonded to carbon, hydrogen, nitrogen, or sulfur, but not carbonate carbon as in CaCO3 nor carbide carbon as in CaC2 or CO or CO2), which vaporize at significant rates. VOCs are probably the second-most widespread and diverse class of emissions after particulates

Solid wastes comprise all the wastes arising from human and animal activities that are normally solid and that are discarded as useless or unwanted. The term solid waste as used in this text is all-inclusive, encompassing the heterogeneous mass of throwaways from the urban community as well as the more homogeneous accumulation of agricultural, industrial

Solid wastes include all solid or semisolid materials that the possessor no longer considers of sufficient value to retain. The management of these waste materials is the fundamental concern of all the activities encompassed in solid waste management—whether the planning level is local, regional or subregional, or state and federal. For this reason, it is important to know as much about municipal solid waste (MSW) as possible. The purpose of this chapter is to identify the sources, types, and composition of solid wastes

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

Important physical characteristics of MSW include specific weight, moisture content, particle size and size distribution, field capacity, and compacted waste porosity. The discussion is limited to an analysis of residential, commercial, and some industrial solid wastes. Note, however, that the fundamentals of analysis presented in this and the following chapter are applicable to all types of solid wastes

An understanding of the nature of wastewater is essential in the design and operation of collection, treatment, and reuse facilities, and in the engineering management of environmental quality. To promote this understanding, the information in this chapter is presented in eight sections dealing with (1) an introduction to the constituents found in wastewater

Attached growth processes can be grouped into three general classes: (1) nonsubmerged attached growth processes, (2) suspended growth processes with fixed-film packing, and (3) submerged attached growth aerobic processes. Nonsubmerged Attached Growth Processes. Trickling filters with rock packing have been a common