00323 Performance rating of glass windows and glass windows with films in aspect of thermal comfort and heat transmission

00323 Performance rating of glass windows and glass windows with films in aspect of thermal comfort and heat transmission

12 Refractories/ceramics (properties, production, applications) parameters can be used along with software for Gibbs energy minimization in order to c...

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12 Refractories/ceramics (properties, production, applications) parameters can be used along with software for Gibbs energy minimization in order to calculate all thermodynamic properties and any phase diagram section or phase equilibrium of interest.

06•00318 Effects of double glazed facade on energy consumption, thermal comfort and condensation for a typical office building in Singapore Wong, N. H. et at. Energy and Buildings, 2005, 37, (6), 563 572. Fully glazed facade that has been increasingly used in Singapore causes higher energy consumption and thermal discomfort due to higher solar gain. The use of double glazed facade system with ventilation systems is one way to solve these problems. The objective of this paper is to investigate the effects of double glazed facade with ventilation system on the energy consumption, thermal comfort and condensation and compare to single glazed facade system. TAS and CFD software were utilized to calculate energy consumption, thermal comfort and condensation for single glazed facade building as well as double glazed facade building. The simulation results showed double glazed facade with natural ventilation were able to minimize energy consumption as well as to enhance the thermal comfort. Turning the mechanical fans on could also solve the condensation problem due to high humidity.

06100319 Energy performance assessment of a window with a horizontal Venetian blind Shahid, H. and Naylor, D. Energy and Buildings, 2005, 37, (8), 836 843. This study examines the effects of the presence of a Venetian blind on the thermal performance of a window. The blind is positioned adjacent to the indoor surface of either a single or double glazed window and the coupled convection and radiation heat transfer problem is solved using a two-dimensional finite volume model. The numerical model is validated with published experimental and numerical results in the literature. The results show that the presence of a Venetian blind significantly improves the energy performance of a single and double glazed window. The blind reduces the overall heat transfer rate through the window by reducing the thermal radiation from the indoor glazing. The improved understanding of the benefits of Venetian blinds may lead to better designs of window/shading systems.

06100320 Glass-ceramic nuclear waste forms obtained from SiO2-AI203-CaO-ZrO2-TiO2 glasses containing lanthanides (Ce, Nd, Eu, Gd, Yb) and actinides (Th): study of internal crystallization Loiseau, P. et al. Journal c~/'Nuclear Materials, 2004, 335, (1), 14 32. Glass-ceramic waste forms such as zirconolite (nominally CaZrTi207) based ones can be envisaged as good candidates for minor actinides or Pu immobilization. Such materials, in which the actinides (or lanthanides used as actinide surrogates) would be preferentially incorporated into zirconolite crystals homogeneously dispersed in a durable glassy matrix, can be prepared by controlled crystallization (nucleation + crystal growth) of parent glasses belonging to the SiO2A1203-CaO-ZrO2-TiO2 system. This work presents the effects of the nature of the minor actinide surrogate (Ce, Nd, Eu, Gd, Yb, Th) on the structure, the microstructure and the composition of the zirconolite crystals formed in the bulk of the glass-ceramics. The amount of lanthanides and thorium incorporated into zirconolite crystals is discussed in relation with the capacity of the glass to accommodate these elements and of the crystals to incorporate them in the calcium and zirconium sites of their structure.

06•00321 Nanodevices that explore the synergies between PDCs and carbon nanotubes Shah, S. R. and Raj, R. Journal c?fthe European Ceramic Society, 2005, 25, (2 3), 243 249. There is now good evidence that carbon nanotubes can be coated uniformly with a very thin, perhaps even a monolayer, of a polymerderived ceramic (SiCN) by a simple process of soaking the nanotube surfaces with the liquid precursor followed by pyrolysis. The ceramic coating bonds the nanotubes to one another, which suppresses timedependent creep that is present without the ceramic bonding. This paper addresses the influence of the ceramic coating on two functional properties of carbon nanotube structures-the electrolytic supercapacitance and electrochemico-mechanical actuation. The results, when expressed as the equivalent surface capacitance of carbon sheets, are quite unexpected. The ceramic coating appears to increase the surface capacitance of the nanotube structure. The actuation induced by capacitive charging is also shown to be somewhat enhanced, although the principal influence of the coating is to suppress the drift of the actuation seen in unbonded carbon nanotube structures. It is inferred that the thickness of the SiCN coating amounts to approximately one monolayer of coverage of the nanotubes.

06•00322 Novel application of ceramic precursors for the fabrication of composites Herzog, A. et al. Join'nat c~f the Em'opecm Ceramic Society, 2005, 25, (2 3), 187 192.

Pre-ceramic polymers are enabling the development of a variety of advanced shaping methods which, in turn, make possible new and costeffective approaches for the fabrication of composite materials. This opens new perspectives for the mass production of composites which might, for example, be used in cost-sensitive areas of application in the machine and automobile industries. In two examples it will be shown how pre-ceramic polymers can be used to obtain both metal matrix composites (MMC) and ceramic matrix composites (CMC). Their properties will be discussed in particular with respect to the usage of a pre-ceramic polymer. The first example shows an approach to manufacturing short-fibre-reinforced CMCs by means of a plastic forming technique which involves mixing of either carbon or SiC fibres, ceramic fillers and a viscous ceramic precursor. The precursor permits a fibre-reinforced ceramic with a low porosity to be obtained. The role of the precursor in the whole process and the resulting material properties will be discussed. The second example shows a method for fabricating porous SiC ceramic preforms which are subsequently infiltrated with aluminium to form a MMC. By using the precursor route, a machinable preform with tailored porosity can be produced. Correlations between precursor, preform and MMC properties will be drawn.

06100323 Performance rating of glass windows and glass windows with films in aspect of thermal comfort and heat transmission Chaiyapinunt, S. e/ al. Energy and Buildings, 2005, 37, (7), 725 738. This article is about a study on glass window and glass window with film of different types in aspect of thermal comfort and heat transmission. Different types of glass window, clear glass, tinted glass, reflective glass, double pane glass, and low-e glass were investigated. Films with different spectral optical properties were then adhered to the glass windows of different types and studied. The analysis was done based on the outside design weather condition which selected from 12 years of Bangkok meteorological data. Predicted percentage of dissatisfied (PPD) was selected as the thermal comfort index. The relative heat gain (RHG) based on local weather condition was selected as the heat transmission index. The PPD can be subdivided into the PPD due to surface temperature effect and the PPD due to solar radiation effect. The analysis indicated that, for most of the glass windows considered except the reflective glasses, the values of PPD due to solar radiation effect were much larger than the values of PPD due to surface temperature effect. And the most discomfort condition occurred when using a clear glass as window. Adhered films to the glass windows caused the PPD due to surface temperature effect increase and cause the PPD due to solar radiation effect decrease. It was also found that the PPD values due to solar radiation effect for glass windows and glass windows with films were varied linearly with the total transmittance of glass windows and glass windows with films. The PPD values due to surface temperature effect were varied with the total absorptance of glass windows and glass windows with films in an ahnost linear fashion. The heat transmission index, RHG, based on chosen design weather condition can be subdivided into the R H G due to conduction effect and RHG due to solar radiation effect. The analysis indicated that the wdues of RHG due to solar radiation effect were larger than the wdues of R H G due to conduction effect for all glass windows and glass windows with films considered in this study. Adhered film to the glass windows resulted in lowering the relative heat gain due to solar radiation in the amount corresponding to the film properties. But the film had very few effect on the relative heat gain due to conduction. The relative heat gain values were wlried linearly with the total transmittances of the glass windows and glass windows with fihns. The relative heat gain values were also varied inversely with the absorptances of glass windows and glass windows with films in a linear fashion.

06100324 Porous ceramic membranes for propanepropylene separation via the ,n-complexation mechanism: unsupported systems Stoitsas, K. A. ef al. Microporous and Mesoporous MaferiaL~', 2005, 78, (2 3), 235 243. The purpose of this work is the utilization of the selective 7rcomplexation interactions exhibited between certain metal cations and the double bond of the olefins, in order to develop membrane materials for a continuous propane-propylene separation process. Mesoporous '~,-A1203 and microporous SiO2 membranes are synthesized by the sol-gel method and subsequently modified with Ag + by impregnation from silver nitrate solutions. Gas separation experiments of equimolar undiluted propane-propylene mixtures resulted in maximum separation factors of 1.3 for the mesoporous systems. For the microporous systems the maximum separation factor achieved was 7.7, which is one of the highest reported in the literature for porous ceramic membrane systems.

Fuel and Energy Abstracts

January 2006

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