1.
As to the air quality, the number of days with air quality recorded above Grade II totalled299 last year, two days less than that of the previous year.
在空气质量方面，全年空气质量等级达到二级以上的天数为299天，比前年减少两天。
2.
The numbers of the days with the air pollution index attaining Grade II and better than Grade II is over 50% in 2001.
2001年全年空气污染指数Ⅱ级和好于Ⅱ级的天数达到50%以上。
3.
national (annual) emissions (of air pollutants)
全国每年的空气污染物排放量
4.
Percentage of the Air Quality Grades in 341 Cities in 2001
2001年度全国341个城市空气质量分级比例
5.
Energy-saving Analysis of an All-year Running Air Conditioning System Equipped with Energy Recovery AHU
能量回收式空气处理机组全年运行节能分析
6.
Seasonal Energy Efficiency Assessment of Air Source Heat Pump Water Heaters
空气源热泵热水机组全年综合能效评定
7.
In recent years ways have been developed by which air can be safely used over and over in space.
近年来创造了一些能在太空中安全地反复利用空气的方法。
8.
Statistical-Dynamic Features of Interdecadal Spatial-temporal Evolution of Regional Climate in East Asia under Global Change Background;
全球变化背景下东亚区域气候年代际时空演变的统计—动力特征
9.
Study on Cold Air Strong Wind of Bohai Sea in Winter and Its Effecting on Safety Navigation;
渤海冬半年冷空气大风及对船舶安全影响的研究
10.
general service compressed air system
全船通用压缩空气系统
11.
air Brake safe control
空气制动安全警惕装置
12.
Air tightness test and safety valve adjusting for main air receiver( control air receiver, air horn receiver) on board.
主空气瓶（制空气瓶、笛空气瓶）船后气密试验和安全阀的调整。
13.
Simulation and Optimized Control for Central Air-Conditioning System with Pure-air Terminals;
全空气中央空调系统仿真与优化控制
14.
BAPMoN Global Atmosphere Watch
本底空气污染监测网全球大气观察
15.
Performance Study of Membrane-based Air to Air Enthalpy Exchanger;
静止式空气—空气全热交换器性能评价研究
16.
Study on Heat Exchange Performance of Air-to-Air Plate Heat Exchange Ventilator
空气—空气板式全热交换器热量回收性能的研究
17.
Air trapped inside a condom could cause it to break.
安全套内藏空气会令安全套破烂。
18.
Clean Air Act Amendment (1987) established a national air-quality standard for ozone.
1987年洁净空气法修正案建立了空气的国家空气质量标准。