Earth & Environmental Sciences
shale gas
81%
shale
61%
methane
42%
air
42%
principal component analysis
28%
chemical
27%
compressor
26%
xylene
24%
residential area
23%
ambient air
22%
natural gas
19%
air sampling
14%
geographical region
13%
separator
12%
toluene
10%
monitoring data
10%
benzene
10%
gas chromatography
10%
county
10%
organic compound
9%
field study
9%
spectrometer
9%
compression
8%
health
7%
well
7%
detection
6%
climate change
6%
sampling
6%
laboratory
5%
monitoring
5%
analysis
2%
effect
2%
Engineering & Materials Science
Shale gas
100%
Shale
89%
Methane
45%
Air
42%
Principal component analysis
27%
Xylene
26%
Compressors
16%
Natural gas
16%
Ethylbenzene
14%
Geographical regions
14%
Mass spectrometers
13%
Sampling
13%
Organic compounds
13%
Gas chromatography
12%
Toluene
11%
Benzene
11%
Monitoring
10%
Climate change
10%
Separators
10%
Compaction
8%
Health
7%
Set theory
6%
Chemical Compounds
Methane
44%
Gas
41%
Compressor
33%
Natural Gas
25%
Sampling
18%
Background Concentration
18%
1,2,4-trimethylbenzene
17%
1,3,5-trimethylbenzene
16%
Ethylbenzene
12%
Gas Chromatography
8%
Toluene
8%
Benzene
7%