Matches in SemOpenAlex for { <https://semopenalex.org/work/W79365619> ?p ?o ?g. }
Showing items 1 to 61 of
61
with 100 items per page.
- W79365619 abstract "Oxygen plays an important role in the first stages of the decomposition of organic substances derived from plant material. The decomposition and reformation of such organic matter as cellulose and lignin leads, through-humification and a sequence of metamorphic processes, to the formation of coal. Initially, oxidation reactions cause the formation of dark-colored humic acids, later under more anaerobic conditions, pressure and higher temperatures, polymerization occurs as the sediment becomes buried. Under these conditions phenolic compounds are more stable, also during the processes of decomposition phenolic substances are more resistant to microorganisms, and thus seem to accumulate. The humification process may be considered as the first step in coalification. It starts by rapid decomposition of the cellulose and by enzymatic degradation of the lignin of the rotting plant substance to form C/sub 6/-C/sub 3/ or C/sub 6/-C/sub 1/ compounds. These lose methoxyl groups and carboxyl groups and can form hydroquinones which may polymerize and combine, forming humic acids. Degradation may proceed also to aliphatic compounds. Most of the reactions seem to lead to benzoquinones which dimerize and polymerize further, causing an increase in aromatization with age, and under more anaerobic conditions later during coalification. When conditions become anaerobic, melanoidin and glucosamin compounds form and nitrogen fixation occurs. This explains the presence of about 1 to 3.5 percent nitrogen in humic acid concentrates, lignin, lignite, subbituminous and bituminous coal. The fixation of nitrogen also results in further reduction of carbon in humic substance during the later stages of humification. Further coalification of buried humified strata of decomposed organic material causes reduction as the methoxyl and oxygen group content decreases, and CO and CO/sub 2/ gases and H/sub 2/O evolve and gradual dehydration occurs." @default.
- W79365619 created "2016-06-24" @default.
- W79365619 creator A5089871347 @default.
- W79365619 date "1976-06-09" @default.
- W79365619 modified "2023-09-27" @default.
- W79365619 title "Oxidation of lignin and cellulose, humification and coalification" @default.
- W79365619 doi "https://doi.org/10.2172/7258299" @default.
- W79365619 hasPublicationYear "1976" @default.
- W79365619 type Work @default.
- W79365619 sameAs 79365619 @default.
- W79365619 citedByCount "0" @default.
- W79365619 crossrefType "report" @default.
- W79365619 hasAuthorship W79365619A5089871347 @default.
- W79365619 hasConcept C124681953 @default.
- W79365619 hasConcept C157021035 @default.
- W79365619 hasConcept C159390177 @default.
- W79365619 hasConcept C159750122 @default.
- W79365619 hasConcept C161790260 @default.
- W79365619 hasConcept C178790620 @default.
- W79365619 hasConcept C185592680 @default.
- W79365619 hasConcept C2779251873 @default.
- W79365619 hasConcept C2779325354 @default.
- W79365619 hasConcept C2780560099 @default.
- W79365619 hasConcept C2780965034 @default.
- W79365619 hasConcept C2781052789 @default.
- W79365619 hasConcept C39432304 @default.
- W79365619 hasConcept C49852136 @default.
- W79365619 hasConcept C52201283 @default.
- W79365619 hasConceptScore W79365619C124681953 @default.
- W79365619 hasConceptScore W79365619C157021035 @default.
- W79365619 hasConceptScore W79365619C159390177 @default.
- W79365619 hasConceptScore W79365619C159750122 @default.
- W79365619 hasConceptScore W79365619C161790260 @default.
- W79365619 hasConceptScore W79365619C178790620 @default.
- W79365619 hasConceptScore W79365619C185592680 @default.
- W79365619 hasConceptScore W79365619C2779251873 @default.
- W79365619 hasConceptScore W79365619C2779325354 @default.
- W79365619 hasConceptScore W79365619C2780560099 @default.
- W79365619 hasConceptScore W79365619C2780965034 @default.
- W79365619 hasConceptScore W79365619C2781052789 @default.
- W79365619 hasConceptScore W79365619C39432304 @default.
- W79365619 hasConceptScore W79365619C49852136 @default.
- W79365619 hasConceptScore W79365619C52201283 @default.
- W79365619 hasLocation W793656191 @default.
- W79365619 hasLocation W793656192 @default.
- W79365619 hasOpenAccess W79365619 @default.
- W79365619 hasPrimaryLocation W793656191 @default.
- W79365619 hasRelatedWork W119894195 @default.
- W79365619 hasRelatedWork W2005824068 @default.
- W79365619 hasRelatedWork W2049306027 @default.
- W79365619 hasRelatedWork W2106358964 @default.
- W79365619 hasRelatedWork W2153436417 @default.
- W79365619 hasRelatedWork W2486063844 @default.
- W79365619 hasRelatedWork W2604655746 @default.
- W79365619 hasRelatedWork W2970252026 @default.
- W79365619 hasRelatedWork W4312182204 @default.
- W79365619 hasRelatedWork W1568279931 @default.
- W79365619 isParatext "false" @default.
- W79365619 isRetracted "false" @default.
- W79365619 magId "79365619" @default.
- W79365619 workType "report" @default.