With the worldwide rise in electric vehicles, the demand for lithium batteries is increasing day by day. In 2015, China＇s new energy vehicles developed rapidly, and the price of lithium carbonate rose from fifty or s...With the worldwide rise in electric vehicles, the demand for lithium batteries is increasing day by day. In 2015, China＇s new energy vehicles developed rapidly, and the price of lithium carbonate rose from fifty or sixty thousand yuan per ton to 150 thousand yuan. In the past, lithium was often extracted from spodumene （LiAlSi2O6）, which is time consuming, laborious and expensive. Over the past decade, abundant lithium has been discovered in brackish and salt water lakes, which is an important way to obtain lithium resources.展开更多
Through the theoretical analysis of overburden destabilization mechanism, FLAC 3D simplified plane numerical simulation method and field measurement method, we compared the relationship of overburden support pressure ...Through the theoretical analysis of overburden destabilization mechanism, FLAC 3D simplified plane numerical simulation method and field measurement method, we compared the relationship of overburden support pressure at 35 m of workface recovery, and the peak overburden support pressure decreased from 13.85 Mpa to 11.97 Mpa from 1:1 to 1:3. With the increase of mining ratio, the peak over-supporting pressure decreases: with the increase of top coal recovery thickness, the peak over-supporting pressure and the influence range will be further expanded, and the distance between the peak over-supporting pressure and the coal wall of the working face will be further increased and the high stress zone of the peak area will be expanded simultaneously.展开更多
An improved method of(NH4)2SO4 roasting followed by water leaching to utilize zinc oxidized ores was studied.The operating parameters were obtained by investigating the effects of the molar ratio of(NH4)2SO4 to zinc,r...An improved method of(NH4)2SO4 roasting followed by water leaching to utilize zinc oxidized ores was studied.The operating parameters were obtained by investigating the effects of the molar ratio of(NH4)2SO4 to zinc,roasting temperature,and holding time on zinc extraction.The roasting process followed the chemical reaction control mechanism with the apparent activation energy value of 41.74 kJ·mol^−1.The transformation of mineral phases in roasting was identified by X-ray diffraction analysis combined with thermogravimetry–differential thermal analysis curves.The water leaching conditions,including the leaching temperature,leaching time,stirring velocity,and liquid-to-solid ratio,were discussed,and the leaching kinetics was studied.The reaction rate was obtained under outer diffusion without product layer control;the values of the apparent activation energy for two stages were 4.12 and 8.19 kJ·mol^−1.The maximum zinc extraction ratio reached 96%while the efficiency of iron extraction was approximately 32%under appropriate conditions.This work offers an effective method for the comprehensive use of zinc oxidized ores.展开更多
The low temperature molten salt method was used to extract potassium from K-feldspar ore, and some related factors including mass ratio between NaNO_3, NaOH, H_2O and K-feldspar ore, particle size of K-feldspar ore,re...The low temperature molten salt method was used to extract potassium from K-feldspar ore, and some related factors including mass ratio between NaNO_3, NaOH, H_2O and K-feldspar ore, particle size of K-feldspar ore,reaction temperature and time were investigated, respectively. In addition, the optimum condition for this method was determined by a series of condition experiments. What was more, the K-feldspar ore and the leach residue after reaction based on the above optimum condition were analyzed by XRD, SEM and EDS,separately. The results of which indicated that the mechanism of extraction of potassium for this method was according to the ion exchange reaction between sodium ion and potassium ion, and the extraction ratio of potassium had an obvious improvement than that of traditional methods, which could reach up to 96.25%.Therefore, this method can be a feasible solution to extract potassium from K-feldspar ore for its low energy consumption and high efficiency.展开更多
Fetr6 is an underground mine using the stope-and-pillar mining method. As there was some evidence regarding pillar failure in this mine, improving works such as roof support and replacing existing pillars with concret...Fetr6 is an underground mine using the stope-and-pillar mining method. As there was some evidence regarding pillar failure in this mine, improving works such as roof support and replacing existing pillars with concrete pillars (CP) were carried out. During the construction of the second CP, in the space between the remaining pillars, one of the pillars failed leading to the progressive failure of other pillars until 4 000 m 2 of mine had collapsed within a few minutes. In this work, this phenomenon is described by applying both numerical and empirical methods and the respective results are compared. The results of numerical modelling are found to be closer to the actual condition than those of the empirical method. Also, a width-to-height (W/H) ratio less than 1, an inadequate support system and the absence of a detailed program for pillar recovery are shown to be the most important causes of the Domino failure in this mine.展开更多
The spores of Ganoderma lucidum were ground and broken to ultrafine particles by high speed centrifugal shearing（HSCS） pulverizer. The characteristics of Ganoderma lucidum spores were analyzed by scanning electron m...The spores of Ganoderma lucidum were ground and broken to ultrafine particles by high speed centrifugal shearing（HSCS） pulverizer. The characteristics of Ganoderma lucidum spores were analyzed by scanning electron microscope （SEM）, Fourier transform infrared spectrophotometry （FTIR）. Ultraviolet-visible pectrophotometer was used to determine the extraction ratio of aqueous solubility polysaccharide between the raw and broken spores. The immunological function on the mice before and after the breaking of spores wan investigated. The experimental results show that after being ground, the sporoderm-broken ratio reachs 100%, the original active ingredients of ganoderma lucidum spores do not change, and the extraction ratio of aqueous solubility polysaccharide is greatly increased by 40.08%. The broken spores show much higher immunological activity comparing with original spores of Ganoderma lucidum.展开更多
文摘With the worldwide rise in electric vehicles, the demand for lithium batteries is increasing day by day. In 2015, China＇s new energy vehicles developed rapidly, and the price of lithium carbonate rose from fifty or sixty thousand yuan per ton to 150 thousand yuan. In the past, lithium was often extracted from spodumene （LiAlSi2O6）, which is time consuming, laborious and expensive. Over the past decade, abundant lithium has been discovered in brackish and salt water lakes, which is an important way to obtain lithium resources.
文摘Through the theoretical analysis of overburden destabilization mechanism, FLAC 3D simplified plane numerical simulation method and field measurement method, we compared the relationship of overburden support pressure at 35 m of workface recovery, and the peak overburden support pressure decreased from 13.85 Mpa to 11.97 Mpa from 1:1 to 1:3. With the increase of mining ratio, the peak over-supporting pressure decreases: with the increase of top coal recovery thickness, the peak over-supporting pressure and the influence range will be further expanded, and the distance between the peak over-supporting pressure and the coal wall of the working face will be further increased and the high stress zone of the peak area will be expanded simultaneously.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.51774070,52004165,and 51574084)and the National Key Research and Development Program of China(No.2017YFB 0305401).
文摘An improved method of(NH4)2SO4 roasting followed by water leaching to utilize zinc oxidized ores was studied.The operating parameters were obtained by investigating the effects of the molar ratio of(NH4)2SO4 to zinc,roasting temperature,and holding time on zinc extraction.The roasting process followed the chemical reaction control mechanism with the apparent activation energy value of 41.74 kJ·mol^−1.The transformation of mineral phases in roasting was identified by X-ray diffraction analysis combined with thermogravimetry–differential thermal analysis curves.The water leaching conditions,including the leaching temperature,leaching time,stirring velocity,and liquid-to-solid ratio,were discussed,and the leaching kinetics was studied.The reaction rate was obtained under outer diffusion without product layer control;the values of the apparent activation energy for two stages were 4.12 and 8.19 kJ·mol^−1.The maximum zinc extraction ratio reached 96%while the efficiency of iron extraction was approximately 32%under appropriate conditions.This work offers an effective method for the comprehensive use of zinc oxidized ores.
基金Supported by the National Natural Science Foundation of China(21373252)Fundamental Research Project of Qing Hai Science&Technology Department(2016-ZJ-749)Qinghai Innovation Fund for Technology Based Firms(2014-GX-Q19)
文摘The low temperature molten salt method was used to extract potassium from K-feldspar ore, and some related factors including mass ratio between NaNO_3, NaOH, H_2O and K-feldspar ore, particle size of K-feldspar ore,reaction temperature and time were investigated, respectively. In addition, the optimum condition for this method was determined by a series of condition experiments. What was more, the K-feldspar ore and the leach residue after reaction based on the above optimum condition were analyzed by XRD, SEM and EDS,separately. The results of which indicated that the mechanism of extraction of potassium for this method was according to the ion exchange reaction between sodium ion and potassium ion, and the extraction ratio of potassium had an obvious improvement than that of traditional methods, which could reach up to 96.25%.Therefore, this method can be a feasible solution to extract potassium from K-feldspar ore for its low energy consumption and high efficiency.
文摘Fetr6 is an underground mine using the stope-and-pillar mining method. As there was some evidence regarding pillar failure in this mine, improving works such as roof support and replacing existing pillars with concrete pillars (CP) were carried out. During the construction of the second CP, in the space between the remaining pillars, one of the pillars failed leading to the progressive failure of other pillars until 4 000 m 2 of mine had collapsed within a few minutes. In this work, this phenomenon is described by applying both numerical and empirical methods and the respective results are compared. The results of numerical modelling are found to be closer to the actual condition than those of the empirical method. Also, a width-to-height (W/H) ratio less than 1, an inadequate support system and the absence of a detailed program for pillar recovery are shown to be the most important causes of the Domino failure in this mine.
基金the National Natural Science Foundation of China(No.50272047)Ministry of Education of China(No.704034)
文摘The spores of Ganoderma lucidum were ground and broken to ultrafine particles by high speed centrifugal shearing（HSCS） pulverizer. The characteristics of Ganoderma lucidum spores were analyzed by scanning electron microscope （SEM）, Fourier transform infrared spectrophotometry （FTIR）. Ultraviolet-visible pectrophotometer was used to determine the extraction ratio of aqueous solubility polysaccharide between the raw and broken spores. The immunological function on the mice before and after the breaking of spores wan investigated. The experimental results show that after being ground, the sporoderm-broken ratio reachs 100%, the original active ingredients of ganoderma lucidum spores do not change, and the extraction ratio of aqueous solubility polysaccharide is greatly increased by 40.08%. The broken spores show much higher immunological activity comparing with original spores of Ganoderma lucidum.
