In this study,the original tourmaline and beryl mineral samples have been collected from a Brazilian pegmatite.The objective of this study was to examine the adsorption behavior of Brazilian ciclosilicate samples,towa...In this study,the original tourmaline and beryl mineral samples have been collected from a Brazilian pegmatite.The objective of this study was to examine the adsorption behavior of Brazilian ciclosilicate samples,towards divalent metals(Pb 2+,Mn 2+,and Zn 2+) in ethanol solution has been studies by a batch technique.The ciclosilicate samples were characterized by elemental analysis,Fourier transform infrared spectroscopy,helium picnometry,mercury porosity,and nitrogen adsorption-desorption.The Langmuir expression for adsorption isotherm was applied in order to determine the adsorption capacity to form a monolayer and the constant related to the adsorption intensity.In aqueous solution there was a significant adsorption increase with the temperature and pronounced synergistic effects were observed.The maximum number of moles adsorbed was determined to be 12.48 and 11.49 mmol/g for systems Pb 2+ /beryl and Pb 2+ /tourmaline,respectively.The energetic effects caused by metal cations adsorption were determined through calorimetric titrations.Thermodynamics indicated the existence of favorable conditions for such Pb 2+-,Mn 2+-,and Zn 2+-OH interactions.展开更多
Lunar dust, the finest fraction of lunar regolith, has undergone important space weathering on the Moon. It not only serves as a record of the evolution of the lunar surface environment and the modification of mineral...Lunar dust, the finest fraction of lunar regolith, has undergone important space weathering on the Moon. It not only serves as a record of the evolution of the lunar surface environment and the modification of mineral properties, but also influences the lunar surface environment through dust transport. Our current understanding of the properties and transport mechanisms of lunar dust on the lunar surface, however, remains limited. With rapid development of lunar exploration, it is necessary to further study the problem and meet the need of future lunar exploration missions. The lunar surface is the primary environmental space where uncrewed lunar rover activity, crewed lunar exploration, and lunar base construction take place. The lunar dust will distribute in such a space area due to electrostatic lifting and impacted sputtering, which will pose a threat to lunar surface exploration activities. In addition, lunar dust transport is closely related to lunar horizon glow, lunar swirl, and lunar magnetic anomaly. Understanding the properties and transport mechanisms of lunar dust is key to comprehending the formation of these scientific phenomena. Therefore, a systematic and in-depth investigation of lunar dust properties and dust transport patterns is urgently required to advance lunar science and implement lunar exploration projects. In this study, we summarize the physical and chemical properties of lunar dust and our understanding of dust transport on the lunar surface, identify remaining challenges and issues in the study of lunar dust, and offer perspectives on this research field.展开更多
基金The authors are indebted to CNPq for fellowships and CAPES for financial support
文摘In this study,the original tourmaline and beryl mineral samples have been collected from a Brazilian pegmatite.The objective of this study was to examine the adsorption behavior of Brazilian ciclosilicate samples,towards divalent metals(Pb 2+,Mn 2+,and Zn 2+) in ethanol solution has been studies by a batch technique.The ciclosilicate samples were characterized by elemental analysis,Fourier transform infrared spectroscopy,helium picnometry,mercury porosity,and nitrogen adsorption-desorption.The Langmuir expression for adsorption isotherm was applied in order to determine the adsorption capacity to form a monolayer and the constant related to the adsorption intensity.In aqueous solution there was a significant adsorption increase with the temperature and pronounced synergistic effects were observed.The maximum number of moles adsorbed was determined to be 12.48 and 11.49 mmol/g for systems Pb 2+ /beryl and Pb 2+ /tourmaline,respectively.The energetic effects caused by metal cations adsorption were determined through calorimetric titrations.Thermodynamics indicated the existence of favorable conditions for such Pb 2+-,Mn 2+-,and Zn 2+-OH interactions.
基金supported by the National Natural Science Foundation of China(No.41931077)the Strategic Priority Program of CAS(No.XDB41020300)+2 种基金the Guizhou Provincial Science and Technology Projects(No.GZ2019SIG)the National Natural Science Foundation of China(L2224032)the Chinese Academy of Sciences(XK2022DXC004).
文摘Lunar dust, the finest fraction of lunar regolith, has undergone important space weathering on the Moon. It not only serves as a record of the evolution of the lunar surface environment and the modification of mineral properties, but also influences the lunar surface environment through dust transport. Our current understanding of the properties and transport mechanisms of lunar dust on the lunar surface, however, remains limited. With rapid development of lunar exploration, it is necessary to further study the problem and meet the need of future lunar exploration missions. The lunar surface is the primary environmental space where uncrewed lunar rover activity, crewed lunar exploration, and lunar base construction take place. The lunar dust will distribute in such a space area due to electrostatic lifting and impacted sputtering, which will pose a threat to lunar surface exploration activities. In addition, lunar dust transport is closely related to lunar horizon glow, lunar swirl, and lunar magnetic anomaly. Understanding the properties and transport mechanisms of lunar dust is key to comprehending the formation of these scientific phenomena. Therefore, a systematic and in-depth investigation of lunar dust properties and dust transport patterns is urgently required to advance lunar science and implement lunar exploration projects. In this study, we summarize the physical and chemical properties of lunar dust and our understanding of dust transport on the lunar surface, identify remaining challenges and issues in the study of lunar dust, and offer perspectives on this research field.
