Because there are plenty of clay particles in the flush fluid of Pingguo Aluminum Mine, the consolidationtechnology in geotechnical engineering was adopted to carry out the disassociation of water and soil disassociat...Because there are plenty of clay particles in the flush fluid of Pingguo Aluminum Mine, the consolidationtechnology in geotechnical engineering was adopted to carry out the disassociation of water and soil disassociation. Inthis method, vacuum method, electro-osmosis and chemical flocculation were used comprehensively to separate soilfrom flush fluid. The experiments of the method of "vacuum + electro-osmosis" for drainage was made. After pretreat-ing the flush fluid, suction pressure was offered by the sand well in the bottom and electro-osmosis was used to drainoff water. The results of the experiment show that the good effect can be obtained in drainage when the electric gradi-ent is greater than 8.3 V/cm and the quantity of sand well is more than 6. In industrial production, it is necessary to in-crease the quantity of sand well, to arrange the electrodes rationally and to set up an intermittent electric circuit. On thebasis of the experiments , the industrial feasible flow was put forward. It may be a helpful attempt to apply consolida-tion technology to the fields of the environmental protection and so on.展开更多
Microcystis aeruginosa, generally occurring in large colonies under natural conditions, mainly exists as single cells in laboratory cultures. The mechanisms involved in colony formation in Microcystis aeruginosa and t...Microcystis aeruginosa, generally occurring in large colonies under natural conditions, mainly exists as single cells in laboratory cultures. The mechanisms involved in colony formation in Microcystis aeruginosa and their roles in algal blooms remain unknown. In this study, based on previous research findings that fluid motion may stimulate the colony formation in green algae, cul^are experiments were conducted under axenic conditions in a circular water chamber where the flow rate, temperature, light, and nutrients were controlled. The number of cells of Microcystis aeruginosa, the number of cells per colony, and the colonial characteristics in various growth phases were observed and measured. The results indicated that the colony formation in Microcystis aeruginosa, which was not observed under stagnant conditions, was evident when there was fluid motion, with the number of cells per largest colony reaching 120 and the proportion of the number of cells in colonial form to the total number of cells and the mean number of cells per colony reaching their peak values at a flow rate of 35 crn/s. Based on the analysis of colony formation process, fluid motion stimulates the colony formation in Microcystis aeruginosa in the lag growth phase, while flushes and disaggregates the colonies in the exponential growth phase. The stimulation effect in the lag growth phase may be attributable to the involvement of fluid motion in a series of physiological processes, including the uptake of trace elements and the synthesis and secretion of polysaccharides. In addition, the experimental groups exhibiting typical colonial characteristics in the lag growth phase were found to have higher cell biomass in the later phase.展开更多
文摘Because there are plenty of clay particles in the flush fluid of Pingguo Aluminum Mine, the consolidationtechnology in geotechnical engineering was adopted to carry out the disassociation of water and soil disassociation. Inthis method, vacuum method, electro-osmosis and chemical flocculation were used comprehensively to separate soilfrom flush fluid. The experiments of the method of "vacuum + electro-osmosis" for drainage was made. After pretreat-ing the flush fluid, suction pressure was offered by the sand well in the bottom and electro-osmosis was used to drainoff water. The results of the experiment show that the good effect can be obtained in drainage when the electric gradi-ent is greater than 8.3 V/cm and the quantity of sand well is more than 6. In industrial production, it is necessary to in-crease the quantity of sand well, to arrange the electrodes rationally and to set up an intermittent electric circuit. On thebasis of the experiments , the industrial feasible flow was put forward. It may be a helpful attempt to apply consolida-tion technology to the fields of the environmental protection and so on.
基金supported by the National Natural Science Foundation of China (Grant No. 50979028)the Special Fund of Research for Public Welfare Industry of the Ministry of Water Resources of China (Grant No. 200801065)
文摘Microcystis aeruginosa, generally occurring in large colonies under natural conditions, mainly exists as single cells in laboratory cultures. The mechanisms involved in colony formation in Microcystis aeruginosa and their roles in algal blooms remain unknown. In this study, based on previous research findings that fluid motion may stimulate the colony formation in green algae, cul^are experiments were conducted under axenic conditions in a circular water chamber where the flow rate, temperature, light, and nutrients were controlled. The number of cells of Microcystis aeruginosa, the number of cells per colony, and the colonial characteristics in various growth phases were observed and measured. The results indicated that the colony formation in Microcystis aeruginosa, which was not observed under stagnant conditions, was evident when there was fluid motion, with the number of cells per largest colony reaching 120 and the proportion of the number of cells in colonial form to the total number of cells and the mean number of cells per colony reaching their peak values at a flow rate of 35 crn/s. Based on the analysis of colony formation process, fluid motion stimulates the colony formation in Microcystis aeruginosa in the lag growth phase, while flushes and disaggregates the colonies in the exponential growth phase. The stimulation effect in the lag growth phase may be attributable to the involvement of fluid motion in a series of physiological processes, including the uptake of trace elements and the synthesis and secretion of polysaccharides. In addition, the experimental groups exhibiting typical colonial characteristics in the lag growth phase were found to have higher cell biomass in the later phase.
