根据第一段第一行 “Airis not just one gas, it is a mixture of different gases,空气不仅仅是一种气体,它是不同气体的一个混合” 可知答案为 C , 空气是不同气体的一个混合;A 项:空气只是一种气体;B 项:空气是两或三种气体的混合,第二段第一句提到 “空气中主要有四种气体” 故 B 错误;D 项:...
The air we breathe in is actually a m___ of different gases, such as oxygen, hydrogen and so on. 答案 答案:mixture.mixture表示"混合物",不定冠词a后接单数可数名词.故填mixture.我们吸入的空气实际上是不同气体的混合物,比如氧气,氢气等.相关推荐 1The air we breathe in is actually a m___ ...
the energy used by green plants to make their own food. These green plants then provide food for all organisms (生物) on the Earth. Much of the energy that comes from the Sun never reaches the Earth's surface. It is either reflected orabsorbed by the gases in the upper atmosphere. ...
Have you ever noticed that the air in the city smells different from that in the country? One of the reasons is that exhausts(排气管) from vehicles give off a lot of bad gases.Today, when we think of air pollution, we should think of transport, especially cars. There are about 24 mil...
A new earth observation satellite is to be launched, tracing different gases and aerosols in the air. British
SF 6 is a gas with excellent dielectric properties and is commonly used in gas-insulated equipment. However it has the high global warming potential. Thus, the development of new gases or gas mixtures for GIS, GIL is strongly desired. For dimensioning the gas insulated systems the support insu...
decrease in concentrations in going from an Arctic to a tropical air mass. Ozone shows the opposite pattern: the largest concentrations are recorded in the tropical air mass and the smallest concentrations in the Arctic air mass. Such gases as CO and SO2show distributions more complex in ...
DHave you ever noticed that the air in the city smellsdifferent from that in the country? One of the reasons isthat exhausts(尾气) from vehicles give off a lot of badgases.Today, when we think of air pollution, we will thinkof transport, especially cars. There are about 23 million...
aGases from cars making the air dirty. Waste water from factories polluted the rivers. But things may be quite different in Dongtan. Dongtan is the world’s first environmentally friendly city. It is on Chongming Island, near Shanghai, and it will be ready in 2030. 气体从使空气的汽车肮脏...
B. Bird, Molecular Theory of Gases and Liquids. Wiley, New York (1954). Google Scholar R. J. Kee, J. Warnatz, J. A. Miller, A Fortran Program Computer Code for the Evaluation of Gas-Phase Viscosities, Conductivities, and Diffusion Coefficients. SANDIA Report SAND83-S209 (1983). ...