Certain non-metallic granules （NMG） were selected as the research object. It was proposed to conduct the volume compression experiments as well as those on the NMG physical properties at high stress levels. Then, no...Certain non-metallic granules （NMG） were selected as the research object. It was proposed to conduct the volume compression experiments as well as those on the NMG physical properties at high stress levels. Then, not only the volume compression ratio curve but also the extended Drucker-Prager linear model were obtained. In addition, through the friction strength tests, parameters of the Mohr-Coulomb model were gained, which proved in basic agreement with those of the extended Drucker-Prager linear model. Additionally, curves of the friction coefficients between the NMG and the sheet metal trader different pressures were also obtained. Based on the material performance experiments, numerical analysis in respect of flexible-die forming process with solid granule medium （SGM） was conducted. The die and device for experiments of solid granule medium forming （SGMF） on sheet metal were designed and manufactured. Typical parabolic parts were successfully trial-produced. The tests and simulation results show that the sheet formability is significantly improved for the extraordinary friction performance during interaction between the SGM and the sheet metal surface. The process control and die structure are simple, and the shaped work-pieces enjoy many advantages, such as satisfactory surface quality and favorable die fitability, which offers a brand-new method and means for processing and preparation of sheet metals.展开更多
The experimental die apparatus of the solid granules medium forming on sheet metal was designed and manufactured.Typical parts,such as conical,parabolic,cylindrical and square-box-shaped components,were successfully t...The experimental die apparatus of the solid granules medium forming on sheet metal was designed and manufactured.Typical parts,such as conical,parabolic,cylindrical and square-box-shaped components,were successfully trial-produced as well.According to the analysis of the changing trends of the cross-section shape and the wall thickness during the process,it can be found that the shape of the free deformation zone of the sheet metal,which is the most critical thinning area,can be described as an approximately spherical cap.According to this forming feature,back pressure deep drawing technology with solid granules medium on sheet metal was proposed to restrain drastic thinning at the bottom of the part through the joint friction effect of solid granules medium,the back pressure tringle and the sheet metal.Therefore,the deep drawing limit of the sheet metal is significantly improved.In order to fabricate thin-walled rotary parts with great drawing ratio and complex cross-sections,a finite element model based on the material property test of the solid granules medium was established to optimize the scheme of the back pressure deep drawing.The effects on the forming performance of sheet metal from back pressure load and the approach of blank holding control were analyzed through this model.展开更多
Alpha-mangostin(AMG),a natural xanthone extracted from Garcinia mangostana Linn,has a variety of pharmacological therapeutic effects such as antioxidant activity,antibacterial activity,anticancer,and anti-inflammatory...Alpha-mangostin(AMG),a natural xanthone extracted from Garcinia mangostana Linn,has a variety of pharmacological therapeutic effects such as antioxidant activity,antibacterial activity,anticancer,and anti-inflammatory[1].However,it has poor aqueous-solubility and dissolution,which results in low bioavailability.Solid self-emulsifying drug delivery system(solid-SEDDS),an effective pharmaceutical strategy,offers the potential for enhancing the oral bioavailability of poorly water-soluble drugs[2].Therefore,solid-SEDDS is of interest as a potential method for enhancing the solubility and dissolution of AMG.展开更多
Sludge granulation and the effect of gas-liquid-solid separator （GLSS） design on the efficiency of upflow anaerobic sludge blanket （UASB） and upflow anaerobic sludge filter （UASF） reactors, operating at HRTs ran...Sludge granulation and the effect of gas-liquid-solid separator （GLSS） design on the efficiency of upflow anaerobic sludge blanket （UASB） and upflow anaerobic sludge filter （UASF） reactors, operating at HRTs ranging from 3 to 12 h was investigated. VSS/TS ratio gradually increased in both the reactors with increasing sludge age （from 0.5 to more than 0.7 for UASB reactor and 0.012 to 0.043 for UASF reactor）. X-Ray diffraction analysis of the UASF sludge showed the presence of expanding clays revealing its additional absorption capability. Fuoraphyllite and albite precipitation related to excellular polymers of the microbial shell structure, showed the extended growth of microorganisms during sludge granulation. A gradual decrease （82%-69%） in COD removal with decreasing HRT was apparent in UASF reactor. In case of UASB reactor, this decrease was marginal because addition of GLSS device significantly improved （14%-20%） the overall efficiency of the UASB reactor. GLSS enhanced the efficiency of the UASB reactor by increasing the settleability of suspended particles and accelerating the coagulation of colloidal particles due to the velocity gradient.展开更多
Iron ore sintering process is the main CO_(2) emission source throughout the integrate steelworks,which primarily comes from the combustion of solid fuels.Improving the combustion efficiency and reducing the solid fue...Iron ore sintering process is the main CO_(2) emission source throughout the integrate steelworks,which primarily comes from the combustion of solid fuels.Improving the combustion efficiency and reducing the solid fuel consumption are important ways to reduce the CO_(2) emission in the sintering process.Around the efficient combustion of fuel,the migration behavior and combustion characteristics of solid fuel in the granulation process were investigated.The results indicated that during the granulation process,fuel particles with size less than 0.5 mm mainly migrated into the granules with grain size of 1-3,3-5 and 5-8 mm;fuel particles with size of 0.5^(-1)mm mainly migrated into granules of 1-3 mm;fuel particles with size of 1-3,3-5 and 5-8 mm mainly entered the granules with the same grain size.With the increase in fuel particles grain size from-0.5 to+8 mm,the combustion efficiency exhibited a firstly-increasing and then decreasing tendency,while the NO_(x) exhibited a decreasing tendency.Potential reason can be described that finer fuel particles(-1 mm)easily distributed in the outer layer of the granules,which combusted fiercely due to its larger specific surface area,leading to the development of incomplete combustion and the conversion of fuel nitrogen;the combustion efficiency of larger fuel particles was restricted by the inner diffusion of O_(2),which then contributed to the reduction of NO_(x) under the inadequate combustion atmosphere.展开更多
基金Project(50775197)supported by the National Natural Science Foundation of China
文摘Certain non-metallic granules （NMG） were selected as the research object. It was proposed to conduct the volume compression experiments as well as those on the NMG physical properties at high stress levels. Then, not only the volume compression ratio curve but also the extended Drucker-Prager linear model were obtained. In addition, through the friction strength tests, parameters of the Mohr-Coulomb model were gained, which proved in basic agreement with those of the extended Drucker-Prager linear model. Additionally, curves of the friction coefficients between the NMG and the sheet metal trader different pressures were also obtained. Based on the material performance experiments, numerical analysis in respect of flexible-die forming process with solid granule medium （SGM） was conducted. The die and device for experiments of solid granule medium forming （SGMF） on sheet metal were designed and manufactured. Typical parabolic parts were successfully trial-produced. The tests and simulation results show that the sheet formability is significantly improved for the extraordinary friction performance during interaction between the SGM and the sheet metal surface. The process control and die structure are simple, and the shaped work-pieces enjoy many advantages, such as satisfactory surface quality and favorable die fitability, which offers a brand-new method and means for processing and preparation of sheet metals.
基金Project(50775197) supported by the National Natural Science Foundation of China
文摘The experimental die apparatus of the solid granules medium forming on sheet metal was designed and manufactured.Typical parts,such as conical,parabolic,cylindrical and square-box-shaped components,were successfully trial-produced as well.According to the analysis of the changing trends of the cross-section shape and the wall thickness during the process,it can be found that the shape of the free deformation zone of the sheet metal,which is the most critical thinning area,can be described as an approximately spherical cap.According to this forming feature,back pressure deep drawing technology with solid granules medium on sheet metal was proposed to restrain drastic thinning at the bottom of the part through the joint friction effect of solid granules medium,the back pressure tringle and the sheet metal.Therefore,the deep drawing limit of the sheet metal is significantly improved.In order to fabricate thin-walled rotary parts with great drawing ratio and complex cross-sections,a finite element model based on the material property test of the solid granules medium was established to optimize the scheme of the back pressure deep drawing.The effects on the forming performance of sheet metal from back pressure load and the approach of blank holding control were analyzed through this model.
文摘Alpha-mangostin(AMG),a natural xanthone extracted from Garcinia mangostana Linn,has a variety of pharmacological therapeutic effects such as antioxidant activity,antibacterial activity,anticancer,and anti-inflammatory[1].However,it has poor aqueous-solubility and dissolution,which results in low bioavailability.Solid self-emulsifying drug delivery system(solid-SEDDS),an effective pharmaceutical strategy,offers the potential for enhancing the oral bioavailability of poorly water-soluble drugs[2].Therefore,solid-SEDDS is of interest as a potential method for enhancing the solubility and dissolution of AMG.
文摘Sludge granulation and the effect of gas-liquid-solid separator （GLSS） design on the efficiency of upflow anaerobic sludge blanket （UASB） and upflow anaerobic sludge filter （UASF） reactors, operating at HRTs ranging from 3 to 12 h was investigated. VSS/TS ratio gradually increased in both the reactors with increasing sludge age （from 0.5 to more than 0.7 for UASB reactor and 0.012 to 0.043 for UASF reactor）. X-Ray diffraction analysis of the UASF sludge showed the presence of expanding clays revealing its additional absorption capability. Fuoraphyllite and albite precipitation related to excellular polymers of the microbial shell structure, showed the extended growth of microorganisms during sludge granulation. A gradual decrease （82%-69%） in COD removal with decreasing HRT was apparent in UASF reactor. In case of UASB reactor, this decrease was marginal because addition of GLSS device significantly improved （14%-20%） the overall efficiency of the UASB reactor. GLSS enhanced the efficiency of the UASB reactor by increasing the settleability of suspended particles and accelerating the coagulation of colloidal particles due to the velocity gradient.
基金supported by the National Natural Science Foundation of China(No.52274344)Provincial Natural Science Foundation of Hunan(No.2022JJ30723)+1 种基金Independent Exploration and Innovation Project of graduate students of Central South University,Hunan Provincial Science and Technology Achievement Transformation and Industrialization Program(No.2020GK4055)China Baowu Low Carbon Metallurgy Innovation Foundation(No.BWLCF202118).
文摘Iron ore sintering process is the main CO_(2) emission source throughout the integrate steelworks,which primarily comes from the combustion of solid fuels.Improving the combustion efficiency and reducing the solid fuel consumption are important ways to reduce the CO_(2) emission in the sintering process.Around the efficient combustion of fuel,the migration behavior and combustion characteristics of solid fuel in the granulation process were investigated.The results indicated that during the granulation process,fuel particles with size less than 0.5 mm mainly migrated into the granules with grain size of 1-3,3-5 and 5-8 mm;fuel particles with size of 0.5^(-1)mm mainly migrated into granules of 1-3 mm;fuel particles with size of 1-3,3-5 and 5-8 mm mainly entered the granules with the same grain size.With the increase in fuel particles grain size from-0.5 to+8 mm,the combustion efficiency exhibited a firstly-increasing and then decreasing tendency,while the NO_(x) exhibited a decreasing tendency.Potential reason can be described that finer fuel particles(-1 mm)easily distributed in the outer layer of the granules,which combusted fiercely due to its larger specific surface area,leading to the development of incomplete combustion and the conversion of fuel nitrogen;the combustion efficiency of larger fuel particles was restricted by the inner diffusion of O_(2),which then contributed to the reduction of NO_(x) under the inadequate combustion atmosphere.
