The differences in organic matter abundance and rock composition between shale and mudstone determine the discrepancy of their contributions to the formation of conventional and shale oil/gas reservoirs.The evaluation...The differences in organic matter abundance and rock composition between shale and mudstone determine the discrepancy of their contributions to the formation of conventional and shale oil/gas reservoirs.The evaluation criteria of source rocks are different in the future exploration in self-sourced petroleum systems.Shales are deposited in deep/semi-deep lacustrine,with low sedimentation rate and chemical depositions of various degrees,while mudstones are mostly formed in shallow lacustrine/lakeside,with high deposition rate and density flow characteristics.Three factors contribute to the enrichment of organic matter in shales,including the"fertility effect"caused by volcanic ash deposition and hydrothermal injection,excessive and over-speed growth of organisms promoted by radioactive materials,and deep-water anaerobic environment and low sedimentation rate to protect the accumulation of organic matter from dilution.Lamellations in shales are easy to be stripped into storage space,and acid water produced during hydrocarbon generation can dissolve some particles to generate new pores.The massive mudstones with high clay content are of poor matrix porosity.Shales with high total organic carbon,developed laminations,relatively good reservoir property,and high brittle mineral content,are the most favorable lithofacies for shale oil exploration and development.It is necessary to conduct investigation on the differences between shale and mudstone reservoirs,to identify resources distribution in shale and mudstone formations,determine the type and standard of"sweet-spot"evaluation parameters,optimize"sweet-spot areas/sections",and adopt effective development technologies,which is of great significance to objectively evaluate the total amount and economy of shale oil resources,as well as the scale of effective exploitation.展开更多
Phenol, a ubiquitous component of industrial effluents, is a common pollutant of water resources and a serious threat to fish.The present work demonstrates that a significant amount of phenol is retained by various ti...Phenol, a ubiquitous component of industrial effluents, is a common pollutant of water resources and a serious threat to fish.The present work demonstrates that a significant amount of phenol is retained by various tissues of the common carp.Cyprinus carpio.and the snake-headed murrel.Channa punclatus.The rate of [^(14)C] phenol accumulation was higher in the carp than in the murrel.It is suggested that retention of phenol in the brain and ovary may seriously afiect the reproductive potential of the fish. 1990 Academic Press.Inc.展开更多
Seedlings of drought-tolerance rice varieties Han 501and Han A03,and the drought sensitive varietiesNanjing 11 and Yanjing 2 were raised in a paddyfield and transplanted into pots at the age of 8leaves.Water stress st...Seedlings of drought-tolerance rice varieties Han 501and Han A03,and the drought sensitive varietiesNanjing 11 and Yanjing 2 were raised in a paddyfield and transplanted into pots at the age of 8leaves.Water stress started at the tillering stage byholding water from 0 MPa of the soil water potentialin pots till the leaves showed seriously wilting.展开更多
The tested soils containing different Cd levels were obtained by mixing the normal cultivated soils with the Cd-contaminated soils taken from the paddies near a mine. Five major categories of vegetables, i.e. cucumber...The tested soils containing different Cd levels were obtained by mixing the normal cultivated soils with the Cd-contaminated soils taken from the paddies near a mine. Five major categories of vegetables, i.e. cucumber, cowpea, Bok choy, radish and lettuce, widely planted in the spring and autumn in Hunan Province, were selected for pool-culture experiments. Results showed that the Cd accumulations varied greatly according to the category of vegetables. The Cd accumulations in cucumber and cowpea growing in soils with high Cd levels (1.5 mg/kg) were within the threshold limits of the national standards, meaning that these two categories are safe to grow in Cd-contaminated soils. For either the cucumber or the cowpea category, there were no significant differences in the Cd accumulations of different genotypes. Most of the tested Bok choy and radish cultivars could grow safely in soils whose Cd levels were below 1.0 mg/kg. In comparison, the Cd accumulations in some cultivars tended to increase sharply as the Cd level in the soil went beyond 1.0 mg/kg. Significant variations were also observed in the Cd accumulations of different genotypes with mounting Cd levels in the soil. Besides, there were no positive correlations between Cd accumulations in plants and Cd levels in soils, indicating large fluctuations and poor ecological stability of Bok choy and radish. Therefore, the planting of Bok choy and radish should be strictly evaluated and controlled in Cdcontaminated regions. The Cd contents of most celtuce cultivars growing in mildlycontaminated soils had already exceeded the threshold limit. Therefore, it is not safe for celtuce to grow in Cd-contaminated environments.展开更多
基金Supported by the China National Science and Technology Major Project(2016ZX05046,2017ZX05001)
文摘The differences in organic matter abundance and rock composition between shale and mudstone determine the discrepancy of their contributions to the formation of conventional and shale oil/gas reservoirs.The evaluation criteria of source rocks are different in the future exploration in self-sourced petroleum systems.Shales are deposited in deep/semi-deep lacustrine,with low sedimentation rate and chemical depositions of various degrees,while mudstones are mostly formed in shallow lacustrine/lakeside,with high deposition rate and density flow characteristics.Three factors contribute to the enrichment of organic matter in shales,including the"fertility effect"caused by volcanic ash deposition and hydrothermal injection,excessive and over-speed growth of organisms promoted by radioactive materials,and deep-water anaerobic environment and low sedimentation rate to protect the accumulation of organic matter from dilution.Lamellations in shales are easy to be stripped into storage space,and acid water produced during hydrocarbon generation can dissolve some particles to generate new pores.The massive mudstones with high clay content are of poor matrix porosity.Shales with high total organic carbon,developed laminations,relatively good reservoir property,and high brittle mineral content,are the most favorable lithofacies for shale oil exploration and development.It is necessary to conduct investigation on the differences between shale and mudstone reservoirs,to identify resources distribution in shale and mudstone formations,determine the type and standard of"sweet-spot"evaluation parameters,optimize"sweet-spot areas/sections",and adopt effective development technologies,which is of great significance to objectively evaluate the total amount and economy of shale oil resources,as well as the scale of effective exploitation.
文摘Phenol, a ubiquitous component of industrial effluents, is a common pollutant of water resources and a serious threat to fish.The present work demonstrates that a significant amount of phenol is retained by various tissues of the common carp.Cyprinus carpio.and the snake-headed murrel.Channa punclatus.The rate of [^(14)C] phenol accumulation was higher in the carp than in the murrel.It is suggested that retention of phenol in the brain and ovary may seriously afiect the reproductive potential of the fish. 1990 Academic Press.Inc.
文摘Seedlings of drought-tolerance rice varieties Han 501and Han A03,and the drought sensitive varietiesNanjing 11 and Yanjing 2 were raised in a paddyfield and transplanted into pots at the age of 8leaves.Water stress started at the tillering stage byholding water from 0 MPa of the soil water potentialin pots till the leaves showed seriously wilting.
文摘The tested soils containing different Cd levels were obtained by mixing the normal cultivated soils with the Cd-contaminated soils taken from the paddies near a mine. Five major categories of vegetables, i.e. cucumber, cowpea, Bok choy, radish and lettuce, widely planted in the spring and autumn in Hunan Province, were selected for pool-culture experiments. Results showed that the Cd accumulations varied greatly according to the category of vegetables. The Cd accumulations in cucumber and cowpea growing in soils with high Cd levels (1.5 mg/kg) were within the threshold limits of the national standards, meaning that these two categories are safe to grow in Cd-contaminated soils. For either the cucumber or the cowpea category, there were no significant differences in the Cd accumulations of different genotypes. Most of the tested Bok choy and radish cultivars could grow safely in soils whose Cd levels were below 1.0 mg/kg. In comparison, the Cd accumulations in some cultivars tended to increase sharply as the Cd level in the soil went beyond 1.0 mg/kg. Significant variations were also observed in the Cd accumulations of different genotypes with mounting Cd levels in the soil. Besides, there were no positive correlations between Cd accumulations in plants and Cd levels in soils, indicating large fluctuations and poor ecological stability of Bok choy and radish. Therefore, the planting of Bok choy and radish should be strictly evaluated and controlled in Cdcontaminated regions. The Cd contents of most celtuce cultivars growing in mildlycontaminated soils had already exceeded the threshold limit. Therefore, it is not safe for celtuce to grow in Cd-contaminated environments.
