Unit 7 Introduction to Environmental Chemistry of the Atmosphere
The quality of the air that living organisms breathe, the nature and level of air pollutants, visibility and atmospheric aesthetics, and even climate are dependent upon chemical phenomena that occur in the atmosphere.
生物呼吸的空气质量，空气污染物的性质和水平，能见度和大气美学，甚至气候取决于发生在大气中的化学现象。
The, in turn are strongly tied to absorption of solar energy, interactions between the gas pha of the atmosphere and small solid particles suspended in it, and interchange of chemical species with the geosphere.
这反过来又与太阳能的吸收、大气中的气相与悬浮在大气中的小固体粒子之间的相互作用以及化学物种与地球圈的交换密切相关。
Chemical reactions in the atmosphere and the chemical nature of atmospheric chemical species are the topic of atmospheric chemistry, which is introduced in this text.
大气中的化学反应和大气化学物种的化学性质是大气化学的主题，本文对此作了介绍。
Chemistry in the atmosphere involves the unpolluted atmosphere, highly polluted atmospheres, and a wide range of gradations in between.
大气中的化学包括未污染的大气、高度污染的大气以及两者之间的各种级别。
The same general phenomena govern all and produce one huge atmospheric cycle, in which there are numerous subcycles.
心越
同样的一般现象支配着所有的一切，并产生了一个巨大的大气周期，其中有许多次循环。
Gaous atmospheric chemical species fall into the following somewhat arbitrary and overlapping classifications: inorganic oxides；oxidants；reductants；organics；photochemically active species；acids；salts；and unstable reactive species。
气态大气化学物种属于下列任意和重叠的分类：无机氧化物；氧化物；还原性物质；有机物；光化学活性物质；酸；盐和不稳定活性物质。
In addition, both solid and liquid particles play a strong role in atmospheric chemistry as sources and sinks for gas-pha species, as sites for surface reactions ( solid particles) , and as bodies for aqueous-pha reactions (liquid droplets)。
此外，固体和液体粒子作为气相物种的源和汇，作为表面反应的中心(固体粒子)和作为水相反应的物体(液滴)，在大气化学中都起着很强的作用。
Two constituents of most importance in atmospheric chemistry are radiant energy from the sun, predominantly in the ultraviolet region of the spectrum, and the hydroxyl radical, HO • .
社区核酸检测
大气化学中影响最大的两个组分：太阳辐射能(主要在光谱的紫外线区)和羟基自由基(Ho·)。
The former provides a way to pump a high level of energy into individual gas molecul
es to start a ries of atmospheric chemical reactions, and the latter is the most important reactive intermediate and “currency” of daytime atmospheric chemical phenomena.
前者为将高能量注入单个气体分子中启动一系列大气化学反应提供了一种途径，后者是白天大气化学现象中最重要的反应中间体和“货币”。
An important aspect of atmospheric chemistry is that many of the process occur in the gas pha where molecules are relatively far apart.
大气化学的一个重要方面是，许多过程发生在分子相距较远的气相中。
Therefore, some reactive species can exist for significantly longer times before reacting than they would in water or in solids. This is especially true in the highly rarefied regions of the stratosphere and above.
因此，一些反应物种在反应前比在水中或固体中存在的时间要长得多。在平流层及以上高度稀薄的地区尤其如此。
Photochemical Process in the Atmosphere
汉堡包做法 夏天小吃The absorption of electromagnetic solar radiation （“ light ，” usually in the ultraviolet region of the electromagnetic spectrum) by chemical species may cau photochemical reactions to occur.
电磁辐射(“光”，通常在电磁波光谱的紫外线区)被化学物种吸收可能导致光化学反应发生。
Photochemical reactions give atmospheric chemistry a unique quality and largely deter mine the nature and ultimate fate of atmospheric chemical species.
光化学反应使大气化学具有独特的性质，在很大程度上阻碍了大气化学物种的性质和最终命运。
带乐的成语 The ability of electromag netic radiation to cau photochemical reactions to occur is a function of its energy, E, which increas with increasing frequency （ν） and decreasing wavelength (λ) according to the relationship,
电磁辐射引起光化学反应的能力是其能量E的函数，E随频率(ν)的增加和波长(λ)的减小
的增加而增大。
In order for a photochemical reaction to occur, a single unit of photochemical energy called a quantum and having an energy of hv, must be absorbed by the reacting species.
为了进行光化学反应，必须吸收一个单一的光化学能单位，即量子能量和hv能量。
If the absorbed light is in the visible region of the sun's spectrum, the absorbing species is colored. Colored NO2 is a common example of such a species in the atmosphere.
如果吸收的光在太阳光谱的可见区域，吸收物种就会着色。有色NO2是大气中这种物种的典型例子。
Nitrogen dioxide, N02 , is one of the most photochemically active species found in a polluted atmosphere. When a molecule such as N02 absorbs radiation of energy hv,
营销技巧>活动主持稿二氧化氮，是在污染的大气中发现的最具光化学活性的物种之一。当像N02这样的分子吸收能量hv辐射英国人英语怎么写。
Electronically excited molecules and atoms are reactive and unstable species in the atmosphere that participate in a wide range of atmospheric chemical process.
电子激发态分子和原子是大气中的反应性和不稳定物种，参与了广泛的大气化学过程。
two other generally reactive and unstable species in the atmosphere are free radicals compod of atoms or molecular fragments with unshared electrons, and ions consisting of charged atoms or molecular fragments.
