Preliminary sink-float experiments on high-sulfur coal was done in some mining areas and carried on elementary analysis, industrial analysis, and ashcontent analysis. Through the experiments, definite middlings, and g...Preliminary sink-float experiments on high-sulfur coal was done in some mining areas and carried on elementary analysis, industrial analysis, and ashcontent analysis. Through the experiments, definite middlings, and gangue, the phase analysis of sulfur was carried on, by which a good understanding of sulfur characters in raw coal was achieved.展开更多
Based on the basic principles of hydrogeology and soil mechanics, studied thegenesis mechanism and control factors of settling of ground surface caused by the drainageof the aquifer in the construction of coal mines, ...Based on the basic principles of hydrogeology and soil mechanics, studied thegenesis mechanism and control factors of settling of ground surface caused by the drainageof the aquifer in the construction of coal mines, and put forward a corresponding calculatingmodel demonstrated by practical example.The study provides mining areas,which are covered with a very thick Quaternary soil layer and abundant ground water, witha theoretical basis aimed at forecasting the settling of ground surface.展开更多
The water abundance of mine floor limestone needs to be solved urgently as the average depth of coal mining in China has increased gradually. A method is presented to discuss water abundance with the numerical and phy...The water abundance of mine floor limestone needs to be solved urgently as the average depth of coal mining in China has increased gradually. A method is presented to discuss water abundance with the numerical and physical layered geoelectrical model being established in the half-space, full-space and full-space with tunnel, respectively. The parameters of water abundance are changed in this study, which includes water quantity, water content and volume of abnormity of water-containing abnormity. Results indicate that the different work fields have different macroscopic influences on the apparent resistivity,and the water abundance parameters of water-containing abnormity have quantitative relationship with the apparent resistivity mean in abnormal regions(three-dimensional space region). The quantitative relationships are shown as following: firstly, the amount of water injection has negative linear correlation with the apparent resistivity mean; secondly, when abnormity is unsaturated, there is a negative power function relationship between water content and apparent resistivity mean; thirdly, the volume of abnormity and apparent resistivity mean behave as a decreasing power function law.展开更多
This study was carried out to assess the leaves and fruits of Grewia mollis, Grewia tenax and Grewia villosa for their potentials to produce high nutritive value fodder under semi-arid conditions. The experiment was c...This study was carried out to assess the leaves and fruits of Grewia mollis, Grewia tenax and Grewia villosa for their potentials to produce high nutritive value fodder under semi-arid conditions. The experiment was conducted at the farm of the College of Natural Resources and Environmental Studies, University of Juba-Khartoum-Sudan. Randomized Complete Block design with three replications was used. Proximate analysis was carried to estimate nutritive value, and mineral contents of leaves, seeds and fruit pulp of the three species. Results indicated significant difference （P ≤ 0.05） in nutritive value of the leaves among the three species; dry matter, ash, and acid detergent factor （ADF） kg/ha, while no significant difference was observed among the species in crude protein （CP） and nutrient detergent factor （NDF） kg/ha. Mineral contents of the leaves of the three species showed variations among the species and seasons. Seeds and fruit pulp were found to have considerable levels of nutrients and mineral contents. The nutritive value of the three species was higher in the rainy season compared to the dry season. The results of this study indicate that the three species can be introduced as a source of fodder in animal production farms and silvopastural systems.展开更多
文摘Preliminary sink-float experiments on high-sulfur coal was done in some mining areas and carried on elementary analysis, industrial analysis, and ashcontent analysis. Through the experiments, definite middlings, and gangue, the phase analysis of sulfur was carried on, by which a good understanding of sulfur characters in raw coal was achieved.
文摘Based on the basic principles of hydrogeology and soil mechanics, studied thegenesis mechanism and control factors of settling of ground surface caused by the drainageof the aquifer in the construction of coal mines, and put forward a corresponding calculatingmodel demonstrated by practical example.The study provides mining areas,which are covered with a very thick Quaternary soil layer and abundant ground water, witha theoretical basis aimed at forecasting the settling of ground surface.
文摘The water abundance of mine floor limestone needs to be solved urgently as the average depth of coal mining in China has increased gradually. A method is presented to discuss water abundance with the numerical and physical layered geoelectrical model being established in the half-space, full-space and full-space with tunnel, respectively. The parameters of water abundance are changed in this study, which includes water quantity, water content and volume of abnormity of water-containing abnormity. Results indicate that the different work fields have different macroscopic influences on the apparent resistivity,and the water abundance parameters of water-containing abnormity have quantitative relationship with the apparent resistivity mean in abnormal regions(three-dimensional space region). The quantitative relationships are shown as following: firstly, the amount of water injection has negative linear correlation with the apparent resistivity mean; secondly, when abnormity is unsaturated, there is a negative power function relationship between water content and apparent resistivity mean; thirdly, the volume of abnormity and apparent resistivity mean behave as a decreasing power function law.
文摘This study was carried out to assess the leaves and fruits of Grewia mollis, Grewia tenax and Grewia villosa for their potentials to produce high nutritive value fodder under semi-arid conditions. The experiment was conducted at the farm of the College of Natural Resources and Environmental Studies, University of Juba-Khartoum-Sudan. Randomized Complete Block design with three replications was used. Proximate analysis was carried to estimate nutritive value, and mineral contents of leaves, seeds and fruit pulp of the three species. Results indicated significant difference （P ≤ 0.05） in nutritive value of the leaves among the three species; dry matter, ash, and acid detergent factor （ADF） kg/ha, while no significant difference was observed among the species in crude protein （CP） and nutrient detergent factor （NDF） kg/ha. Mineral contents of the leaves of the three species showed variations among the species and seasons. Seeds and fruit pulp were found to have considerable levels of nutrients and mineral contents. The nutritive value of the three species was higher in the rainy season compared to the dry season. The results of this study indicate that the three species can be introduced as a source of fodder in animal production farms and silvopastural systems.
