Documents disponibles écrits par cet auteur

Adsorption behavior of Li+ onto nano-lithium ion sieve from hybrid magnesium/lithium manganese oxide / Liyan Tian in Chemical engineering journal, Vol. 156 N° 1 (Janvier 2010) 

Public ISBD [article]  in Chemical engineering journal > Vol. 156 N° 1 (Janvier 2010) . - pp. 134-140 Titre : Adsorption behavior of Li+ onto nano-lithium ion sieve from hybrid magnesium/lithium manganese oxide Type de document : texte imprimé Auteurs : Liyan Tian, Auteur ; Wei Ma, Auteur ; Mei Han, Auteur Année de publication : 2010 Article en page(s) : pp. 134-140 Note générale : Génie Chimique Langues : Anglais (eng) Mots-clés : Adsorption  Lithium  Lithium  ion  sieve  Modeling  Kinetics Index. décimale : 660 Résumé : Magnesium (II) doped spinel lithium manganese oxide (LMS) was synthesized by soft chemical method and nanosized ion sieve manganese oxide (HMS) was prepared by extracting lithium and magnesium from LMS. The characteristics of HMS were studied by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, surface areas and determination of pH at the point of zero charge. Experiments were performed to study the effects of pH, adsorbent dose, contact time and Li+ concentration. The competitive model was used to describe the competition between Li+–H+ and the applicability of different kinetic models was evaluated. The results showed that the pH at the point of zero charge of HMS was about 7.8. The recycle of HMS explained that it could be used as Li+ adsorbent with topotactical extraction of lithium. Under optimized batch conditions up to 99.2% Li+ could be recovered from solution within 24 h. The adsorption process followed the pseudo-second-order model and followed an intraparticle diffusion model at the beginning. DEWEY : 660 ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TFJ-4XF840K-8&_user=6 [...] [article] Adsorption behavior of Li+ onto nano-lithium ion sieve from hybrid magnesium/lithium manganese oxide [texte imprimé] / Liyan Tian, Auteur ; Wei Ma, Auteur ; Mei Han, Auteur . - 2010 . - pp. 134-140. Génie Chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 156 N° 1 (Janvier 2010) . - pp. 134-140 Mots-clés : Adsorption  Lithium  Lithium  ion  sieve  Modeling  Kinetics Index. décimale : 660 Résumé : Magnesium (II) doped spinel lithium manganese oxide (LMS) was synthesized by soft chemical method and nanosized ion sieve manganese oxide (HMS) was prepared by extracting lithium and magnesium from LMS. The characteristics of HMS were studied by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, surface areas and determination of pH at the point of zero charge. Experiments were performed to study the effects of pH, adsorbent dose, contact time and Li+ concentration. The competitive model was used to describe the competition between Li+–H+ and the applicability of different kinetic models was evaluated. The results showed that the pH at the point of zero charge of HMS was about 7.8. The recycle of HMS explained that it could be used as Li+ adsorbent with topotactical extraction of lithium. Under optimized batch conditions up to 99.2% Li+ could be recovered from solution within 24 h. The adsorption process followed the pseudo-second-order model and followed an intraparticle diffusion model at the beginning. DEWEY : 660 ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TFJ-4XF840K-8&_user=6 [...]

Analysis of the deformation of embankments on the Qinghai-Tibet railway / Wei Ma in Journal of geotechnical and geoenvironmental engineering, Vol. 134 n°11 (Novembre 2008) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 134 n°11 (Novembre 2008) . - pp. 1645–1654 Titre : Analysis of the deformation of embankments on the Qinghai-Tibet railway Type de document : texte imprimé Auteurs : Wei Ma, Auteur ; Jilin Qi, Auteur Année de publication : 2009 Article en page(s) : pp. 1645–1654 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : Rail  transportation  Permafrost  Embankments  Deformation  Monitoring  China Résumé : Temperature changes and deformations were monitored on various embankment types on the Qinghai-Tibet Railway. Some of these embankments utilized permafrost protection techniques such as duct ventilation, crushed-rock embankments, crushed-rock protected slopes, or thermal-insulation treatments. Some embankments were built conventionally without considering permafrost protection. It was found that the majority of the deformations on both the permafrost-protected and the conventionally built embankments were due to deformation of warm frozen layers closely related to the temperature changes in the underlying permafrost. However, it was found that building embankments with permafrost protection reduced the magnitude of the settlements. After 2–3years , deformation of all the embankments with permafrost protection countermeasures became smaller and smaller, whereas deformation was still increasing in the conventional embankments, where the settlement in the underlying permafrost could reach a considerable level, and could be a potential trigger for embankment failure. This should be taken into consideration in the railway engineering project on the Qinghai-Tibet Plateau. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A11%281 [...] [article] Analysis of the deformation of embankments on the Qinghai-Tibet railway [texte imprimé] / Wei Ma, Auteur ; Jilin Qi, Auteur . - 2009 . - pp. 1645–1654. Geotechnical and geoenvironmental engineering Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 134 n°11 (Novembre 2008) . - pp. 1645–1654 Mots-clés : Rail  transportation  Permafrost  Embankments  Deformation  Monitoring  China Résumé : Temperature changes and deformations were monitored on various embankment types on the Qinghai-Tibet Railway. Some of these embankments utilized permafrost protection techniques such as duct ventilation, crushed-rock embankments, crushed-rock protected slopes, or thermal-insulation treatments. Some embankments were built conventionally without considering permafrost protection. It was found that the majority of the deformations on both the permafrost-protected and the conventionally built embankments were due to deformation of warm frozen layers closely related to the temperature changes in the underlying permafrost. However, it was found that building embankments with permafrost protection reduced the magnitude of the settlements. After 2–3years , deformation of all the embankments with permafrost protection countermeasures became smaller and smaller, whereas deformation was still increasing in the conventional embankments, where the settlement in the underlying permafrost could reach a considerable level, and could be a potential trigger for embankment failure. This should be taken into consideration in the railway engineering project on the Qinghai-Tibet Plateau. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A11%281 [...]