权威例句
Using of Wide Stopes in Coalless Zones Mined by Shovels and BackhoesDiscussion on the Method for Rapidly and Forcibly Passing Coalless Columns on the Fully Mechanized Coalfacethe present condition of coalless mine and the major technology of the safety-licenseStudy: Coal less healthy than nuclear: ; Analyses compare direct, indirect costs of each energy sourcePitt, CMU and WVU Study Ways to Make Coal Less PollutingMethod of drilling of coal pillarTHE APPLICATION OF ELECTROMAGNETIC SURVEYOUTLINING THE RESIDUAL COALBODIES INVOLCANIC ROCK REGIONInfluence of Coal Size on the Performance of Corex ProcessMethod for preparation of coal derived fuel and electricity by a novel co-generation systemAn anatomy of the geographical concentration of Canadian manufacturing industries