Arsenic is a highly toxic element and its contamination in water bodies is a worldwide problem. Arsenic adsorption with metal oxides/hydroxides-based adsorbents is an effective approach to remove arsenic species from ...Arsenic is a highly toxic element and its contamination in water bodies is a worldwide problem. Arsenic adsorption with metal oxides/hydroxides-based adsorbents is an effective approach to remove arsenic species from water for the health of both human beings and the environment. However, no material criterion had been proposed for the selection of potential candidates. Equally puzzling is the fact that no clear explanation was available on the poor arsenic adsorption performance of some commonly used adsorbents, such as active carbon or silica. Furthermore, in-depth examination was also not available for the dramatically different competing adsorption effects of various anions on the arsenic adsorption. Through the arsenic adsorption mechanism study on these highly efficient arsenic adsorbents, we found that ionic potential could be used as a general material criterion for the selection of highly efficient arsenic adsorbents and such a criterion could help us to understand the above questions on arsenic adsorbents. This material criterion could be further applied to the selection of highly efficient adsorbents based on ligand exchange between their surface hydroxyl groups and adsorbates in general, which may be used for the prediction of novel adsorbents for the removal of various contaminations in water.展开更多
Bibliographic reports on the electric conductivity of pure homoionic montmorillonite at low water content were analyzed in order to stress a general behavior of conductivity. At low water content, the conductivity is ...Bibliographic reports on the electric conductivity of pure homoionic montmorillonite at low water content were analyzed in order to stress a general behavior of conductivity. At low water content, the conductivity is attributed to a mechanism of charge transport involving protons due to the influence of the electric field of the exchangeable cations on water molecules at the solvation shell. Conductivity was analyzed in relation with the polarizing power （ionic potential） of the exchangeable cations and with the influence of the connectivity within samples. The general conclusion stressed is that the connectivity due to the association between 2：1 unit layers （clay fabric） is the main factor on the experimental or ＂macroscopic＂ electric conductivity of pure homoionic montmorillonite at low water content. Considerations on the experimental conditions of different bibliographic reports were also made. The conclusion and the considerations made on experimental conditions are a good starting point for future researches on electric conductivity ofhomoionic montmorillonite at low water content.展开更多
Room temperature ionic liquids(RTILs) are non-volatile organic salts. They may replace conventional coalescing agents in latex coating thus reducing volatile organic compounds(VOCs) emission as well as improving perfo...Room temperature ionic liquids(RTILs) are non-volatile organic salts. They may replace conventional coalescing agents in latex coating thus reducing volatile organic compounds(VOCs) emission as well as improving performance of latex coating products such as better thermal stability, conductivity, and antifouling property. The formation of latex coating containing RTILs can be achieved by encapsulation of RTILs inside particles via miniemulsion polymerization. In this study, the role of RTILs and its concentration on stability of miniemulsion during storage and polymerization were investigated. It has been found that, above a critical concentration(10 wt%), adding more RTILs to oil phase may weaken miniemulsion stability during storage as well as polymerization. Such observations were consistent with the zeta potential measurement for miniemulsions prepared at the similar conditions. The results obtained here would be a useful guideline for the development of new waterborne coating products with desirable functions and particle sizes.展开更多
In 2003,Railsback proposed the Earth Scientist's Periodic Table,which displays a great deal of elemental geology information in accordance with the natural environment of the earth.As an applied science,metallurgy...In 2003,Railsback proposed the Earth Scientist's Periodic Table,which displays a great deal of elemental geology information in accordance with the natural environment of the earth.As an applied science,metallurgy is based on mineral composition and element behavior,that is similar to geochemistry.In this paper,connections and similarities between geology and metallurgy are identified,based on geochemical laws and numerous metallurgical cases.An obvious connection is that simple cations w让h high and low ionic potential are commonly extracted by hydrometallurgy,while those with intermediate ionic potential are extracted by pyrometallurgy.In addition,element affinity in geology is associated with element migration in metallurgic phases.To be specific,in pyrometallurgy,lithophile elements tend to gather in slags,chalcophile elements prefer the matte phase,siderophile elements are easily absorbed into metal melt,and atmophile elements readily enter the gas phase.Furthermore,in hydrometallurgy,the principles of hard/soft acids and bases(HSABs)offer an explanation of how precipitation and dissolution occur in different solutions,especially for fluoride and chloride.This article provides many metallurgical examples based on the principles of geochemistry to verify these similarities and connections.展开更多
基金supported by the Knowledge Innovation Program of Institute of Metal Research,Chinese Academy of Sciences(Grant No.Y0N5A111A1)the Youth Innovation Promotion Association,Chinese Academy of Sciences(Grant No.Y2N5711171)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry,China
文摘Arsenic is a highly toxic element and its contamination in water bodies is a worldwide problem. Arsenic adsorption with metal oxides/hydroxides-based adsorbents is an effective approach to remove arsenic species from water for the health of both human beings and the environment. However, no material criterion had been proposed for the selection of potential candidates. Equally puzzling is the fact that no clear explanation was available on the poor arsenic adsorption performance of some commonly used adsorbents, such as active carbon or silica. Furthermore, in-depth examination was also not available for the dramatically different competing adsorption effects of various anions on the arsenic adsorption. Through the arsenic adsorption mechanism study on these highly efficient arsenic adsorbents, we found that ionic potential could be used as a general material criterion for the selection of highly efficient arsenic adsorbents and such a criterion could help us to understand the above questions on arsenic adsorbents. This material criterion could be further applied to the selection of highly efficient adsorbents based on ligand exchange between their surface hydroxyl groups and adsorbates in general, which may be used for the prediction of novel adsorbents for the removal of various contaminations in water.
文摘Bibliographic reports on the electric conductivity of pure homoionic montmorillonite at low water content were analyzed in order to stress a general behavior of conductivity. At low water content, the conductivity is attributed to a mechanism of charge transport involving protons due to the influence of the electric field of the exchangeable cations on water molecules at the solvation shell. Conductivity was analyzed in relation with the polarizing power （ionic potential） of the exchangeable cations and with the influence of the connectivity within samples. The general conclusion stressed is that the connectivity due to the association between 2：1 unit layers （clay fabric） is the main factor on the experimental or ＂macroscopic＂ electric conductivity of pure homoionic montmorillonite at low water content. Considerations on the experimental conditions of different bibliographic reports were also made. The conclusion and the considerations made on experimental conditions are a good starting point for future researches on electric conductivity ofhomoionic montmorillonite at low water content.
基金the Low Carbon Automation Manufacture Innovation Team 2011B81006 for the PhD studentshipNingbo Natural Science Foundation funding 2012A610094
文摘Room temperature ionic liquids(RTILs) are non-volatile organic salts. They may replace conventional coalescing agents in latex coating thus reducing volatile organic compounds(VOCs) emission as well as improving performance of latex coating products such as better thermal stability, conductivity, and antifouling property. The formation of latex coating containing RTILs can be achieved by encapsulation of RTILs inside particles via miniemulsion polymerization. In this study, the role of RTILs and its concentration on stability of miniemulsion during storage and polymerization were investigated. It has been found that, above a critical concentration(10 wt%), adding more RTILs to oil phase may weaken miniemulsion stability during storage as well as polymerization. Such observations were consistent with the zeta potential measurement for miniemulsions prepared at the similar conditions. The results obtained here would be a useful guideline for the development of new waterborne coating products with desirable functions and particle sizes.
基金This work was financially supported by the Key Program of National Natural Science Foundation of China(51334008).
文摘In 2003,Railsback proposed the Earth Scientist's Periodic Table,which displays a great deal of elemental geology information in accordance with the natural environment of the earth.As an applied science,metallurgy is based on mineral composition and element behavior,that is similar to geochemistry.In this paper,connections and similarities between geology and metallurgy are identified,based on geochemical laws and numerous metallurgical cases.An obvious connection is that simple cations w让h high and low ionic potential are commonly extracted by hydrometallurgy,while those with intermediate ionic potential are extracted by pyrometallurgy.In addition,element affinity in geology is associated with element migration in metallurgic phases.To be specific,in pyrometallurgy,lithophile elements tend to gather in slags,chalcophile elements prefer the matte phase,siderophile elements are easily absorbed into metal melt,and atmophile elements readily enter the gas phase.Furthermore,in hydrometallurgy,the principles of hard/soft acids and bases(HSABs)offer an explanation of how precipitation and dissolution occur in different solutions,especially for fluoride and chloride.This article provides many metallurgical examples based on the principles of geochemistry to verify these similarities and connections.
