大三环境工程专业英语期末复习

环境科学Environmental science。环境工程Environmental engineering。定性环境科学Qualitative environmental science。定量环境科学Quantitative environmental science。研究和发展Research and development。分支科学Subdisciplines。环境破坏Environmental disturbance。胡乱收集magpie collection。卫生问题sanition problems。揭示大的差别expose the considerable gaps。虫媒传播Arthropod-borne。外来物质Foreign matter。收集数据Data collection。废物最小化Waste minimization。氧化剂Oxidizer。正常浓度The normal concentration。环境工程师The environmental engineer。闭合回路Closed loop。不完全燃烧Incomplete combustion。二氧化硫Sulfur dioxide。三氧化硫sulphur trioxide。二氧化碳Carbon dioxide。点源Point source。一次大气污染物Primary air pollutant。二次大气污染物secondary air pollutant。额外津贴dividend。液滴Liquid Droplet。酸雨Acid rain。微生物Microbe。沙漠化Desertification。火山喷发V olcano eruptions。设备维护facilities maintenance。空气质量检测Air quality monittoring。风化Wind erosion。氯化物和硫化物Chlorides and sulfide。石油精炼Petroleum refining。新陈代谢率Metabolic rate。活性炭Activated carbon。化石燃料Fossil fuel。需氧量Oxygen demand。氧含量Oxygen content。质量控制Quality control。海轮Ocean liner。衡量浓度Constant strength。挥发性化学物质volatile chemicals。间歇源Intermittent sources。设备改造Equipment modifications。

What Is Air Pollution? Air pollution is normally defined as air that contains one or more chemicals in high enough concentrations to harm humans, other animals, vegetation or materials. There are two major types of air pollutants .A primary air pollutant is a chemical added directly to the air that occurs in a harmful concentration. It can be a natural air component, such as carbon dio xide, that rises above its normal concentration, or something not usually found in the air, such as a lead compound emitted by cars burning leaded gasoline. A secondary air pollutant is a harmful che mical formed in the atmosphere through a chemical reaction among air components. Serious air po llution usually results over a city or other area that is emitting high levels of pollutants during a pe riod of air stagnation. The geographic location of some heavily populated cities, such as Los Ange les and Mexico City, makes them particularly susceptible to frequent air stagnation and pollution b uildup.

We must be careful about depending solely on concentration values in determinimg th e severity air pollutants. By themselves, measured concentrations tell us nothing about the danger caused by pollutants, because threshold levels, synergy, and biological ma gnification are also determining factors. In addition, we run into the issue of conflictin g views of what constitutes harm.

The relationship between polluted water and disease was firmly established with the cholera epide mic of 1854 in London, England. Protection of public health, the original purpose of pollution con trol, continues to be the primary objective in many areas. However, preservation of water resource s, protection of fishing areas, and maintenance of recreational waters are additional concerns today . Water pollution problems intensified following World War II when dramatic increases in urban d ensity and industrialization occurred. Concern over water pollution reached a peak in the mid-seve nties.

Municipal wastewater, also called sewage, is a complex mixture containing water (usually over 99 percent) together with organic and inorganic contaminants, both suspended and dissolved. The co ncentration of these contaminants is normally very low and is expressed in mg/L, that is, milligra ms of contaminant per liter of the mixture. This is a weight-to-volume ratio used to indicate conce ntrations of constituents in water, wastewater, industrial wastes, and other dilute solutions.