A senior eitizen shows off his acrobatic skills to an impressed audience at a public exercise park. As more and more Chinese become Increasingly health conscious, the exercise equipment in public parks is becoming pop...A senior eitizen shows off his acrobatic skills to an impressed audience at a public exercise park. As more and more Chinese become Increasingly health conscious, the exercise equipment in public parks is becoming popular with people of all ages.展开更多
The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization ...The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization related to various hydrothermal fluid circulations. Petromineralogical studies indicate a rich mineral paragenesis with a minimum of seven mineralization phases and, at least, six pyrite generations. As is also the case for galena and native silver, native gold is observed for the first time as inclusion in quartz which opens up, thus, new perspectives for prospecting and evaluating the potential for noble metals associated with the mineralization. Scanning Electron Microscope--Energy Dispersive Spectroscopy and Transmission electron microscopy analyses show, in addition, a large incorporation of trace elements, including Ag and Au, in mineral structures such as fahlores(tetrahedrite-tennantite) and chalcopyrite ones. The mineral/mineral associations, used as geothermometers, gave estimated temperatures for the mineralizing fluids varying from 254 to 330 ℃ for phase Ⅲ, from 254 to 350 ℃ for phase Ⅳ, and from 200 to 300 ℃ for phases Ⅴ and Ⅵ. The seventh and last identified mineralization phase, marked by a deposit of native gold, reflects a drop in the mineralizing fluid’s temperature(< 200 ℃) compatible with boiling conditions. Such results open up perspectives for the development of precious metal research and the revaluation of the Cu–Fe ore deposit at the Ain El Bey abandoned mine, as well as at the surrounding areas fitting in the geodynamic framework of the Africa-Europe plate boundary.展开更多
The technique of derivative constant energy synchronous fluorimetry was intro-duced in this article. For mixture of fluorene, acenaphthene, anthracene and perylene, thedetection limit is 2. 4, 17.1, 0.27, 0.043 ng/mL,...The technique of derivative constant energy synchronous fluorimetry was intro-duced in this article. For mixture of fluorene, acenaphthene, anthracene and perylene, thedetection limit is 2. 4, 17.1, 0.27, 0.043 ng/mL, respectively, when first-derivative con-stant energy synchronous fluorimetry is employed. The detectlon limit is 1. 5, 15. 0, 0.13,0. 022 ng/mL, respectively, when second-derivative constant energy synchronous fluorlme-try is employed. In the method, four compounds can be simultaneously determined withoutany mutual interference.展开更多
AIM To study the chemical constituents from the mycelia of Hypomyces sp. METHODS Silica gel column chromatography was employed for the isolation and purification. The structure of compound 1 was elucidated on the basi...AIM To study the chemical constituents from the mycelia of Hypomyces sp. METHODS Silica gel column chromatography was employed for the isolation and purification. The structure of compound 1 was elucidated on the basis of spectral analysis. RESULTS and CONCLUSION A new perylenequinone, named hypomycin B 1, was isolated from the mycelia of Hypomyces sp.展开更多
文摘A senior eitizen shows off his acrobatic skills to an impressed audience at a public exercise park. As more and more Chinese become Increasingly health conscious, the exercise equipment in public parks is becoming popular with people of all ages.
基金funded by the “Laboratoire de Recherche Ressources, Matériaux et Ecosystémes”, University of Carthage 7021 Zarzouna, Bizerte, Tunisia
文摘The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization related to various hydrothermal fluid circulations. Petromineralogical studies indicate a rich mineral paragenesis with a minimum of seven mineralization phases and, at least, six pyrite generations. As is also the case for galena and native silver, native gold is observed for the first time as inclusion in quartz which opens up, thus, new perspectives for prospecting and evaluating the potential for noble metals associated with the mineralization. Scanning Electron Microscope--Energy Dispersive Spectroscopy and Transmission electron microscopy analyses show, in addition, a large incorporation of trace elements, including Ag and Au, in mineral structures such as fahlores(tetrahedrite-tennantite) and chalcopyrite ones. The mineral/mineral associations, used as geothermometers, gave estimated temperatures for the mineralizing fluids varying from 254 to 330 ℃ for phase Ⅲ, from 254 to 350 ℃ for phase Ⅳ, and from 200 to 300 ℃ for phases Ⅴ and Ⅵ. The seventh and last identified mineralization phase, marked by a deposit of native gold, reflects a drop in the mineralizing fluid’s temperature(< 200 ℃) compatible with boiling conditions. Such results open up perspectives for the development of precious metal research and the revaluation of the Cu–Fe ore deposit at the Ain El Bey abandoned mine, as well as at the surrounding areas fitting in the geodynamic framework of the Africa-Europe plate boundary.
文摘The technique of derivative constant energy synchronous fluorimetry was intro-duced in this article. For mixture of fluorene, acenaphthene, anthracene and perylene, thedetection limit is 2. 4, 17.1, 0.27, 0.043 ng/mL, respectively, when first-derivative con-stant energy synchronous fluorimetry is employed. The detectlon limit is 1. 5, 15. 0, 0.13,0. 022 ng/mL, respectively, when second-derivative constant energy synchronous fluorlme-try is employed. In the method, four compounds can be simultaneously determined withoutany mutual interference.
文摘AIM To study the chemical constituents from the mycelia of Hypomyces sp. METHODS Silica gel column chromatography was employed for the isolation and purification. The structure of compound 1 was elucidated on the basis of spectral analysis. RESULTS and CONCLUSION A new perylenequinone, named hypomycin B 1, was isolated from the mycelia of Hypomyces sp.
