Thermogenic gas, which is generated during the thermal evolution of medium rank coal, is the main source of coalbed methane (CBM).
Zhundong lignite, possessing medium rank among the three coal samples, exhibits the highest formation ability of ultrafine PM0.2, indicating a prominent effect of mineral content over that of coal rank on PM formation.
If the data sets have values with the same rank, we used a medium rank (for example, if the second and third data points were the same rank, the rank was 2.5).
Zhang et al. simulated the absolute adsorption and excess adsorption capacity of medium rank coal to CO2, CH4, and C2H6 gas using molecular dynamics, and provided a theoretical support for improving coalbed methane recovery using CO2 injection.
8% found it "very difficult", 29% said it was "rather difficult", 36% gave a medium ranking ("some comparisons more difficult than others"), 18% thought it was "not very difficult" and 8% claimed they had "no problems at all" in completing the DCE.
2% assessed the ratings as "very difficult", 26% said it was "rather difficult", 43% gave a medium ranking ("some comparisons more difficult than others"), 24% thought it was "not very difficult" and 5% claimed they had "no problems at all" in completing the DCE.
This ratio places Portugal at the medium ranking in the European context.
The low exposure sub-sample had the same power as the full sample followed by the high and medium rank samples.
In the 1960s, investigators ranked each work site from 1 to 10 for its potential arsenic exposure and classified each site as "heavy" (ranks 8 10), "medium" (ranks 4 7), or "light" (ranks 1 3) arsenic exposure areas (Lee and Fraumeni 1969).
Although respondents who spent more than 20 minutes travelling and/or waiting for care were twice as likely to lack regular care overall, this OR was 4.5 in the medium rank, 3.2 in the high rank and non-significant in the low exposure area.
