The internal mechanism of the high hydrophobicity of the coal samples from the Pingdingshan mining area was studied through industrial,element,and surface functional group analysis.Laboratory testing and molecular dyn...The internal mechanism of the high hydrophobicity of the coal samples from the Pingdingshan mining area was studied through industrial,element,and surface functional group analysis.Laboratory testing and molecular dynamics simulations were employed to study the impact of three types of surfactants on the surface adsorption properties and wettability of highly hydrophobic bituminous coal.The results show that the surface of highly hydrophobic bituminous coal is compact,rich in inorganic minerals,and poorly wettable and that coal molecules are dominated by hydrophobic functional groups of aromatic rings and aliphatic structures.The wetting performance of surfactants as the intermediate carrier to connect coal and water molecules is largely determined by the interaction force between surfactants and coal(Fs-c)and the interaction force between surfactants and water(Fs-w),which effectively improve the wettability of modified coal dust via modifying its surface electrical properties and surface energy.A new type of wetting agent with a dust removal rate of 89%has been developed through discovery of a compound wetting agent solution with optimal wetting and settling performance.This paper provides theoretical and technical support for removing highly hydrophobic bituminous coal dust in underground mining.展开更多
Road dust has great adverse effects on traffic quality,traffic safety,atmospheric environment quality,and human health.Therefore,with the continuous development of modern science and technology,the research of road du...Road dust has great adverse effects on traffic quality,traffic safety,atmospheric environment quality,and human health.Therefore,with the continuous development of modern science and technology,the research of road dust suppressants is also progressing.To promote the rational application and development of road dust suppressants,the research progress and prospects of them are analyzed in this paper.It includes a basic overview of road dust suppressants,the main types,the usage and precautions,and the main development direction.It is hoped that this analysis can provide some reference for further research and development of road dust suppressants.展开更多
The components of dust-suppressant were determined based on the analysis on characteristics and mechanisms of road dust raising in open-pit mines. The components were initially selected from moisture agent, coagulatio...The components of dust-suppressant were determined based on the analysis on characteristics and mechanisms of road dust raising in open-pit mines. The components were initially selected from moisture agent, coagulation agent and surfactant. The optimal formulation was determined based on orthogonal test and using the water loss rate as the evaluation index. The performances of moisture releasing and adsorption, wind resistance of optimal formulation in the natural environment were tested. The results show that the formula obtained in experiments provide a good performance of moisture absorption and water retention, and it also had a good dust preventing and controlling performance due to its high surface strength and consolidation under dry conditions. It has good application prospects considering the wide variety of sources for materials and the simple preparation process.展开更多
To relieve dust pollution in open cut coal mines and reduce the hazards of coal dust pollution to the environment and workers we optimized the synthesis of a dust suppressant by graft copolymerization of environmental...To relieve dust pollution in open cut coal mines and reduce the hazards of coal dust pollution to the environment and workers we optimized the synthesis of a dust suppressant by graft copolymerization of environmentally friendly soy protein isolate with methyl methacrylate.This dust suppressant could effectively control dust pollution in open cut coal mines. The optimized conditions for graft copolymerization in this case were determined by a response surface experiment designed with Design-Expert 10 software. Characterization by scanning electron microscopy showed a significant morphology change of the dust suppressant and the generation of a rigid and dense layer on its surface after interacting with coal dust.The layer exhibited good bonding and dust suppression performance. The analysis with Fourier-transform infrared spectroscopy revealed the appearance of new absorption peaks near 1300, 1072, and 1631 cm, demonstrating effective graft copolymerization. The proposed dust suppressant exhibited excellent wind erosion resistance, with a resistance that exceeded 90% at a wind speed of 6.5 m/sec. The successful graft copolymerization and effective bonding and curing of the dust suppressant on coal dust were experimentally verified.This is of great significance to the control of coal dust pollution.展开更多
Dust is an environmental and health hazard.In this study,a new technology for dust suppressant is introduced using soybean urease with an optimal cementing solution.Calcium carbonate is produced by soybean urease and ...Dust is an environmental and health hazard.In this study,a new technology for dust suppressant is introduced using soybean urease with an optimal cementing solution.Calcium carbonate is produced by soybean urease and cementing solution,which bonds the soil particles towards a dust suppressant.A laboratory wind tunnel test is carried out to examine its effectiveness and discover possible optimization solutions.Several factors,including soybean meal concentration,cementing solution concentration,and volume of solution per unit area,are examined to quantify their influences on soil transport mass,evaporation ratio,evaporation rate,surface strength,water retention ratio,and infiltration rate of soil treated by different dust suppressants.Field tests are conducted to explore the performance of this method in the natural environment.The results show that compared with other dust suppressants,the optimized soybean urease has the smallest evaporation rate,a moderate infiltration rate,the largest water retention ratio and surface strength.The indexes of soybean urease for dust suppressant are found to be better than traditional materials.In the natural environment,soybean urease has a stronger anti-disturbance ability.This study concludes that soybean urease dust suppressant has great application potential as a cheap and green method.展开更多
This study aimed to list the medicinal plants used as an appetite suppressant in Hauts-Bassins areas of Burkina Faso. An ethnobotanical survey was undertaken from September to November 2021 using a semi-structured que...This study aimed to list the medicinal plants used as an appetite suppressant in Hauts-Bassins areas of Burkina Faso. An ethnobotanical survey was undertaken from September to November 2021 using a semi-structured questionnaire. To determine well-known families and species, some indices such as Family Importance Value (FIV) and Relative Frequency of Citation (RFC) were calculated respectively. Sixty-seven traditional healers (41 men and 26 women) have been interviewed. The age group from 41 to 60 years old was more represented (47.76%). Fifty-eight (58) plant species belonging to 29 families and 53 genera were recorded to have appetite suppressant properties. Fabaceae family (25%) was the most mentioned followed by Combretaceae (12%). The most mentioned species were Guierasenegalensis (7.64%), Parkiabiglobosa (6.18%), Annona senegalensis and Gardenia erubescens (5.35% for both). Leaves and fruits had the highest frequencies of use with 41% and 25% respectively. The decoction (49.62%) was the main preparation method. The oral route was the only mode of drug administration. These results would contribute to strengthening the database on the medicinal plants used as an appetite suppressant by the traditional healers in Burkina Faso.展开更多
Coal dust is a primary threat to underground coal miners.The most common approach to control coal dust is hydraulic methods,such as water spray and coal seam water injection.To improve the dust suppressant efficiency ...Coal dust is a primary threat to underground coal miners.The most common approach to control coal dust is hydraulic methods,such as water spray and coal seam water injection.To improve the dust suppressant efficiency of hydraulic methods,a novel chemical composite dust suppressant,called NCZ,was prepared in this study using calcium chloride(CaCl_(2)),magnesium chloride(MgCl_(2)),and nonionic surfactants using a thermal synthesis method.The water-retaining properties of NCZ powder and its solutions were characterized using the water absorption rate(WAR)and evaporation rate(ER),respectively,and the wetting abilities of the NCZ solutions on coal dust were tested using the initial contact angle(ICA)and sink rate(SR).The results indicate that the NCZ solutions have anti-evaporation effects,and the ER of the solution with a 20.0 wt%NCZ is reduced by 11.7%compared with that of clean water.Furthermore,NCZ solutions have remarkable enhancement effects on the wettability of coal dust.The ICA and SR of clean water and the NCZ solution at 20.0 wt%are 141.9°and 0 mg/s,and 29.3°and 1.46 mg/s,respectively.Finally,quantitative relationships between the solution surface tension and the ICA and IR were established using the least squares method.This study provides a new product for dust suppression in underground mines,which is significant for the optimum applied con-centration of dust suppressant in mining operations.展开更多
Green roofs are exposed to high winds and harsh environmental conditions that can degrade vegetation and erode substrate material,with negative consequences to ecosystem services.Biochar has been promoted as an effect...Green roofs are exposed to high winds and harsh environmental conditions that can degrade vegetation and erode substrate material,with negative consequences to ecosystem services.Biochar has been promoted as an effective substrate additive to enhance plant performance,but unprocessed biochars are susceptible to wind and water erosion.Applications of granulated biochars or chemical dust suppressants are suggested as a means to mitigate biochar and substrate erosion;however,research on biochar type and chemical dust suppressant use on biochar and substrate erosion is lacking.Vegetation is a crucial factor that influences substrate erosion,yet plant responses may vary with biochar type and chemical dust suppressant;thus,the effects of possible mitigation measures on biochar and substrate erosion are unclear.We investigated the effects of surface-applied granulated and unprocessed biochars and an organic dust suppressant(Entac™)on biochar and substrate erosion on green roofs with Sedum album L.and a native plant mix.Our results show that 94%of unprocessed biochars were lost from green roofs after 2 years regardless of the Entac™amendment,likely due to the lightweight nature and fragmentation of biochar particles.In contrast,granulation of biochars reduced the biochar erosion and total substrate erosion by 74%and 39%,respec-tively,possibly due to enhanced biochar bulk density and particle size and improved moisture retention of biochar-amended substrates.Additionally,Sedum album better reduced biochar and substrate erosion than the native plant mix,likely due to rapid development of high vegetation cover that reduced wind exposure and enhanced substrate moisture retention.We conclude that applications of granulated biochars can substantially reduce biochar and sub-strate erosion on green roofs,improving green roof sustainability.展开更多
文摘The internal mechanism of the high hydrophobicity of the coal samples from the Pingdingshan mining area was studied through industrial,element,and surface functional group analysis.Laboratory testing and molecular dynamics simulations were employed to study the impact of three types of surfactants on the surface adsorption properties and wettability of highly hydrophobic bituminous coal.The results show that the surface of highly hydrophobic bituminous coal is compact,rich in inorganic minerals,and poorly wettable and that coal molecules are dominated by hydrophobic functional groups of aromatic rings and aliphatic structures.The wetting performance of surfactants as the intermediate carrier to connect coal and water molecules is largely determined by the interaction force between surfactants and coal(Fs-c)and the interaction force between surfactants and water(Fs-w),which effectively improve the wettability of modified coal dust via modifying its surface electrical properties and surface energy.A new type of wetting agent with a dust removal rate of 89%has been developed through discovery of a compound wetting agent solution with optimal wetting and settling performance.This paper provides theoretical and technical support for removing highly hydrophobic bituminous coal dust in underground mining.
文摘Road dust has great adverse effects on traffic quality,traffic safety,atmospheric environment quality,and human health.Therefore,with the continuous development of modern science and technology,the research of road dust suppressants is also progressing.To promote the rational application and development of road dust suppressants,the research progress and prospects of them are analyzed in this paper.It includes a basic overview of road dust suppressants,the main types,the usage and precautions,and the main development direction.It is hoped that this analysis can provide some reference for further research and development of road dust suppressants.
文摘The components of dust-suppressant were determined based on the analysis on characteristics and mechanisms of road dust raising in open-pit mines. The components were initially selected from moisture agent, coagulation agent and surfactant. The optimal formulation was determined based on orthogonal test and using the water loss rate as the evaluation index. The performances of moisture releasing and adsorption, wind resistance of optimal formulation in the natural environment were tested. The results show that the formula obtained in experiments provide a good performance of moisture absorption and water retention, and it also had a good dust preventing and controlling performance due to its high surface strength and consolidation under dry conditions. It has good application prospects considering the wide variety of sources for materials and the simple preparation process.
基金supported by the National key R & D plan for the 13th five year plan (No. 2017YFC0805200)the Qingdao science and technology plan project (No.19-3-2-6-zhc)+1 种基金the Natural Science Foundation of Shandong Province (No. ZR2019MEE118)the National Natural Science Foundation of China (No. 51974179)。
文摘To relieve dust pollution in open cut coal mines and reduce the hazards of coal dust pollution to the environment and workers we optimized the synthesis of a dust suppressant by graft copolymerization of environmentally friendly soy protein isolate with methyl methacrylate.This dust suppressant could effectively control dust pollution in open cut coal mines. The optimized conditions for graft copolymerization in this case were determined by a response surface experiment designed with Design-Expert 10 software. Characterization by scanning electron microscopy showed a significant morphology change of the dust suppressant and the generation of a rigid and dense layer on its surface after interacting with coal dust.The layer exhibited good bonding and dust suppression performance. The analysis with Fourier-transform infrared spectroscopy revealed the appearance of new absorption peaks near 1300, 1072, and 1631 cm, demonstrating effective graft copolymerization. The proposed dust suppressant exhibited excellent wind erosion resistance, with a resistance that exceeded 90% at a wind speed of 6.5 m/sec. The successful graft copolymerization and effective bonding and curing of the dust suppressant on coal dust were experimentally verified.This is of great significance to the control of coal dust pollution.
基金The first four authors would like to acknowledge the National Natural Science Foundation of China(No.51508163)the Postgraduate Education Reform and Quality Improvement Project of Henan Province(No.YJS2021JD13)+2 种基金the Training Program for Young Scholar in Colleges and Universities of Henan Province(No.2019GGJS041)the Key-Area Research and Development Program of Guangdong Province(No.2020B0101130009)the Guangdong Enterprise Key Laboratory for Urban Sensing,Monitoring and Early Warning(No.2020B121202019).
文摘Dust is an environmental and health hazard.In this study,a new technology for dust suppressant is introduced using soybean urease with an optimal cementing solution.Calcium carbonate is produced by soybean urease and cementing solution,which bonds the soil particles towards a dust suppressant.A laboratory wind tunnel test is carried out to examine its effectiveness and discover possible optimization solutions.Several factors,including soybean meal concentration,cementing solution concentration,and volume of solution per unit area,are examined to quantify their influences on soil transport mass,evaporation ratio,evaporation rate,surface strength,water retention ratio,and infiltration rate of soil treated by different dust suppressants.Field tests are conducted to explore the performance of this method in the natural environment.The results show that compared with other dust suppressants,the optimized soybean urease has the smallest evaporation rate,a moderate infiltration rate,the largest water retention ratio and surface strength.The indexes of soybean urease for dust suppressant are found to be better than traditional materials.In the natural environment,soybean urease has a stronger anti-disturbance ability.This study concludes that soybean urease dust suppressant has great application potential as a cheap and green method.
文摘This study aimed to list the medicinal plants used as an appetite suppressant in Hauts-Bassins areas of Burkina Faso. An ethnobotanical survey was undertaken from September to November 2021 using a semi-structured questionnaire. To determine well-known families and species, some indices such as Family Importance Value (FIV) and Relative Frequency of Citation (RFC) were calculated respectively. Sixty-seven traditional healers (41 men and 26 women) have been interviewed. The age group from 41 to 60 years old was more represented (47.76%). Fifty-eight (58) plant species belonging to 29 families and 53 genera were recorded to have appetite suppressant properties. Fabaceae family (25%) was the most mentioned followed by Combretaceae (12%). The most mentioned species were Guierasenegalensis (7.64%), Parkiabiglobosa (6.18%), Annona senegalensis and Gardenia erubescens (5.35% for both). Leaves and fruits had the highest frequencies of use with 41% and 25% respectively. The decoction (49.62%) was the main preparation method. The oral route was the only mode of drug administration. These results would contribute to strengthening the database on the medicinal plants used as an appetite suppressant by the traditional healers in Burkina Faso.
基金We much appreciate the National Nature Science Foundation of China(Nos.51874015 and 51574017)the National Key Research and Development Program of China(No.2017YFC0805204).
文摘Coal dust is a primary threat to underground coal miners.The most common approach to control coal dust is hydraulic methods,such as water spray and coal seam water injection.To improve the dust suppressant efficiency of hydraulic methods,a novel chemical composite dust suppressant,called NCZ,was prepared in this study using calcium chloride(CaCl_(2)),magnesium chloride(MgCl_(2)),and nonionic surfactants using a thermal synthesis method.The water-retaining properties of NCZ powder and its solutions were characterized using the water absorption rate(WAR)and evaporation rate(ER),respectively,and the wetting abilities of the NCZ solutions on coal dust were tested using the initial contact angle(ICA)and sink rate(SR).The results indicate that the NCZ solutions have anti-evaporation effects,and the ER of the solution with a 20.0 wt%NCZ is reduced by 11.7%compared with that of clean water.Furthermore,NCZ solutions have remarkable enhancement effects on the wettability of coal dust.The ICA and SR of clean water and the NCZ solution at 20.0 wt%are 141.9°and 0 mg/s,and 29.3°and 1.46 mg/s,respectively.Finally,quantitative relationships between the solution surface tension and the ICA and IR were established using the least squares method.This study provides a new product for dust suppression in underground mines,which is significant for the optimum applied con-centration of dust suppressant in mining operations.
基金the Natural Sciences and Engineering Research Council of Canada(NSERC)to Sean C.Thomas.
文摘Green roofs are exposed to high winds and harsh environmental conditions that can degrade vegetation and erode substrate material,with negative consequences to ecosystem services.Biochar has been promoted as an effective substrate additive to enhance plant performance,but unprocessed biochars are susceptible to wind and water erosion.Applications of granulated biochars or chemical dust suppressants are suggested as a means to mitigate biochar and substrate erosion;however,research on biochar type and chemical dust suppressant use on biochar and substrate erosion is lacking.Vegetation is a crucial factor that influences substrate erosion,yet plant responses may vary with biochar type and chemical dust suppressant;thus,the effects of possible mitigation measures on biochar and substrate erosion are unclear.We investigated the effects of surface-applied granulated and unprocessed biochars and an organic dust suppressant(Entac™)on biochar and substrate erosion on green roofs with Sedum album L.and a native plant mix.Our results show that 94%of unprocessed biochars were lost from green roofs after 2 years regardless of the Entac™amendment,likely due to the lightweight nature and fragmentation of biochar particles.In contrast,granulation of biochars reduced the biochar erosion and total substrate erosion by 74%and 39%,respec-tively,possibly due to enhanced biochar bulk density and particle size and improved moisture retention of biochar-amended substrates.Additionally,Sedum album better reduced biochar and substrate erosion than the native plant mix,likely due to rapid development of high vegetation cover that reduced wind exposure and enhanced substrate moisture retention.We conclude that applications of granulated biochars can substantially reduce biochar and sub-strate erosion on green roofs,improving green roof sustainability.
