Documents disponibles écrits par cet auteur

Calculation of moisture distribution in early-age concrete / Zhang, Jun in Journal of engineering mechanics, Vol. 135 N° 8 (Août 2009) 

Public ISBD [article]  in Journal of engineering mechanics > Vol. 135 N° 8 (Août 2009) . - pp. 871-880 Titre : Calculation of moisture distribution in early-age concrete Type de document : texte imprimé Auteurs : Zhang, Jun, Auteur ; Qi, Kun, Auteur ; Huang, Yu, Auteur Article en page(s) : pp. 871-880 Note générale : Mécanique appliquée Langues : Anglais (eng) Mots-clés : Concrete  Aging  Moisture  Humidity. Résumé : The moisture content in concrete pores is a critical parameter for most of the degradation processes suffered by concrete, such as concrete shrinkage and related cracking. The objective of this paper is to present the formulation of a general moisture distribution model for young-age concrete. In the modeling, both cement hydration and moisture diffusion resulted humidity variations are taken into account synchronously. The effect of initial water distribution (after concrete casting) on the development of moisture distribution is considered by introducing a critical time parameter. The simulation of humidity reduction produced from self-desiccation is based on cement hydration degree that taking the effect of temperature into account by using the equilibrant age concept. During modeling the moisture diffusion, a multilinear model was adopted to simulate the moisture dependent diffusivity. The developed model and finite deferential method can well predict the moisture distribution as well as its variations with time. Good agreement between model predictions and experimental results is found. These results can subsequently be used in shrinkage induced stress field analyses, and further be used for cracking control of concrete structures. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/vsearch/servlet/VerityServlet?KEY=JENMDT&smode=strres [...] [article] Calculation of moisture distribution in early-age concrete [texte imprimé] / Zhang, Jun, Auteur ; Qi, Kun, Auteur ; Huang, Yu, Auteur . - pp. 871-880. Mécanique appliquée Langues : Anglais (eng) in Journal of engineering mechanics > Vol. 135 N° 8 (Août 2009) . - pp. 871-880 Mots-clés : Concrete  Aging  Moisture  Humidity. Résumé : The moisture content in concrete pores is a critical parameter for most of the degradation processes suffered by concrete, such as concrete shrinkage and related cracking. The objective of this paper is to present the formulation of a general moisture distribution model for young-age concrete. In the modeling, both cement hydration and moisture diffusion resulted humidity variations are taken into account synchronously. The effect of initial water distribution (after concrete casting) on the development of moisture distribution is considered by introducing a critical time parameter. The simulation of humidity reduction produced from self-desiccation is based on cement hydration degree that taking the effect of temperature into account by using the equilibrant age concept. During modeling the moisture diffusion, a multilinear model was adopted to simulate the moisture dependent diffusivity. The developed model and finite deferential method can well predict the moisture distribution as well as its variations with time. Good agreement between model predictions and experimental results is found. These results can subsequently be used in shrinkage induced stress field analyses, and further be used for cracking control of concrete structures. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/vsearch/servlet/VerityServlet?KEY=JENMDT&smode=strres [...]

Low-energy distillation-membrane separation process / Huang, Yu in Industrial & engineering chemistry research, Vol. 49 N° 8 (Avril 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 8 (Avril 2010) . - pp. 3760–3768 Titre : Low-energy distillation-membrane separation process Type de document : texte imprimé Auteurs : Huang, Yu, Auteur ; Richard W. Baker, Auteur ; Leland M. Vane, Auteur Année de publication : 2010 Article en page(s) : pp. 3760–3768 Langues : Anglais (eng) Mots-clés : Energy  Distillation-membrane  Separation  process Résumé : A low-energy separation process combining distillation and membrane vapor permeation is introduced as an alternative to conventional distillation. The process can be applied to any liquid mixture for which appropriate selective membranes are available. However, in this paper, the discussion is limited to water/organic solvent mixtures using membranes that preferentially permeate water. Such membranes are available. The process is illustrated with two mixtures: ethanol (light component)/water (heavy component) and acetic acid (heavy component)/water (light component) mixtures. In both cases, the combination process reduces the energy consumption of the separation to half that of simple distillation. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901545r [article] Low-energy distillation-membrane separation process [texte imprimé] / Huang, Yu, Auteur ; Richard W. Baker, Auteur ; Leland M. Vane, Auteur . - 2010 . - pp. 3760–3768. Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 8 (Avril 2010) . - pp. 3760–3768 Mots-clés : Energy  Distillation-membrane  Separation  process Résumé : A low-energy separation process combining distillation and membrane vapor permeation is introduced as an alternative to conventional distillation. The process can be applied to any liquid mixture for which appropriate selective membranes are available. However, in this paper, the discussion is limited to water/organic solvent mixtures using membranes that preferentially permeate water. Such membranes are available. The process is illustrated with two mixtures: ethanol (light component)/water (heavy component) and acetic acid (heavy component)/water (light component) mixtures. In both cases, the combination process reduces the energy consumption of the separation to half that of simple distillation. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901545r