This series of study focused on analysing and assessing the changes of the physical and chemical characteristics of the surfaces of the masonrystones and bricks during the sandblasting cleaning process by conducting v...This series of study focused on analysing and assessing the changes of the physical and chemical characteristics of the surfaces of the masonrystones and bricks during the sandblasting cleaning process by conducting various physical and chemical tests. Seven masonry stones and bricks were adopted, including yellow sandstone, red sandstone, limestone, marble, granite, white clay brick and yellow clay brick. The physical testing included evaluating the cleaning degree, determining the Vickers hardness, and detecting the water absorption. Using a digital imaging analysis method, the greyscale and cleanness were introduced to quantitatively assess the effectiveness of masonry building cleaning and confirmed to be useful and appropriate. The cleanness analysis, together with the hardness and water absorption tests showed that a masonry stone or a brick with a higher cleaning degree corresponded to a brighter and harder stone surface. In general, the physical properties were found to vary largely during the building cleaning.展开更多
This series of study focused on analysing and assessing the Changes of the physical and chemical characteristics of the stone surfaces during the sandblasting cleaning process by conducting various physical and chemic...This series of study focused on analysing and assessing the Changes of the physical and chemical characteristics of the stone surfaces during the sandblasting cleaning process by conducting various physical and chemical tests. Seven masonry stones and bricks were adopted, including yellow sandstone, red sandstone, limestone, marble, granite, white clay brick and yellow clay brick. The chemical investigations included the micrographing of the stone facade and the analysis of the chemical elements and compounds on four of the seven stones and bricks before and after the cleaning using the Scanning Electron Microscope （SEM） and Energy-Dispersive X-ray Spectroscopy （EDX） techniques. In general, the chemical properties were found to vary largely during the building cleaning. The chemical tests showed that the chemical elements and compounds on the stone facade significantly varied after long term exposures to the atmosphere, mainly due to the soiling on the building fagade caused by environmental erosion and weathering.展开更多
The present study investigated potential effectiveness of certain chemical candidates for controlling internal phosphorus loading, and for delineating inactivation pattern in sediment depths of an eutrophic pond under...The present study investigated potential effectiveness of certain chemical candidates for controlling internal phosphorus loading, and for delineating inactivation pattern in sediment depths of an eutrophic pond under simulated mesocosm condition. Chemical administration （@ 30 mg/dm3） resulted in phosphate precipitation from water column concomitant with inactivation in sediments, under specific pH range and/or redox regime. The alum-lime combination dosing wrought the maximum reduction in orthophosphate （65.6%） and soluble reactive phosphate （71.9%） in water plus the utmost increment in sediment-P （0.257 ppm）. The inactivated P forms typically exhibited a downhill concentration gradient with highest sequestration in the uppermost sediment stratum. Ironbound P displayed the highest mobility while calcium- and aluminum- bound P behaved almost immune to internal feedback dynamics. The combo-treatment was established as the most effective phosphate scavenging and confiscating agent, to be adopted as chemical remediation regime for de-eutrophication, restoration and rehabilitation of the water body.展开更多
Fe^(2+)dissolution method and manual method were used to remove the anode slime and their effects on properties of cast Pb−0.6wt.%Ag anode and zinc electrowinning were compared.The results reveal that the Fe^(2+)disso...Fe^(2+)dissolution method and manual method were used to remove the anode slime and their effects on properties of cast Pb−0.6wt.%Ag anode and zinc electrowinning were compared.The results reveal that the Fe^(2+)dissolution method can avoid mechanical damage to the oxide film layer on the anode surface,which cannot be achieved by traditional manual method.This can lower the anode corrosion rate by 57.14%,thus reducing Pb contamination in electrolyte and zinc products.Meanwhile,compared with manual method,Fe^(2+)dissolution method can significantly improve the electrocatalytic activity of the anode and lower the initial power consumption of zinc electrowinning to 2720 kW·h/t after removing anode slime.展开更多
文摘This series of study focused on analysing and assessing the changes of the physical and chemical characteristics of the surfaces of the masonrystones and bricks during the sandblasting cleaning process by conducting various physical and chemical tests. Seven masonry stones and bricks were adopted, including yellow sandstone, red sandstone, limestone, marble, granite, white clay brick and yellow clay brick. The physical testing included evaluating the cleaning degree, determining the Vickers hardness, and detecting the water absorption. Using a digital imaging analysis method, the greyscale and cleanness were introduced to quantitatively assess the effectiveness of masonry building cleaning and confirmed to be useful and appropriate. The cleanness analysis, together with the hardness and water absorption tests showed that a masonry stone or a brick with a higher cleaning degree corresponded to a brighter and harder stone surface. In general, the physical properties were found to vary largely during the building cleaning.
文摘This series of study focused on analysing and assessing the Changes of the physical and chemical characteristics of the stone surfaces during the sandblasting cleaning process by conducting various physical and chemical tests. Seven masonry stones and bricks were adopted, including yellow sandstone, red sandstone, limestone, marble, granite, white clay brick and yellow clay brick. The chemical investigations included the micrographing of the stone facade and the analysis of the chemical elements and compounds on four of the seven stones and bricks before and after the cleaning using the Scanning Electron Microscope （SEM） and Energy-Dispersive X-ray Spectroscopy （EDX） techniques. In general, the chemical properties were found to vary largely during the building cleaning. The chemical tests showed that the chemical elements and compounds on the stone facade significantly varied after long term exposures to the atmosphere, mainly due to the soiling on the building fagade caused by environmental erosion and weathering.
文摘The present study investigated potential effectiveness of certain chemical candidates for controlling internal phosphorus loading, and for delineating inactivation pattern in sediment depths of an eutrophic pond under simulated mesocosm condition. Chemical administration （@ 30 mg/dm3） resulted in phosphate precipitation from water column concomitant with inactivation in sediments, under specific pH range and/or redox regime. The alum-lime combination dosing wrought the maximum reduction in orthophosphate （65.6%） and soluble reactive phosphate （71.9%） in water plus the utmost increment in sediment-P （0.257 ppm）. The inactivated P forms typically exhibited a downhill concentration gradient with highest sequestration in the uppermost sediment stratum. Ironbound P displayed the highest mobility while calcium- and aluminum- bound P behaved almost immune to internal feedback dynamics. The combo-treatment was established as the most effective phosphate scavenging and confiscating agent, to be adopted as chemical remediation regime for de-eutrophication, restoration and rehabilitation of the water body.
基金supported by Zhejiang Libo Industrial Co.,Ltd.,Shaoxing,China。
文摘Fe^(2+)dissolution method and manual method were used to remove the anode slime and their effects on properties of cast Pb−0.6wt.%Ag anode and zinc electrowinning were compared.The results reveal that the Fe^(2+)dissolution method can avoid mechanical damage to the oxide film layer on the anode surface,which cannot be achieved by traditional manual method.This can lower the anode corrosion rate by 57.14%,thus reducing Pb contamination in electrolyte and zinc products.Meanwhile,compared with manual method,Fe^(2+)dissolution method can significantly improve the electrocatalytic activity of the anode and lower the initial power consumption of zinc electrowinning to 2720 kW·h/t after removing anode slime.
