01784 Smart glazing solutions to glare and solar gain: a ‘sick building’ case study

13 Alternative energy supplies (biofuels and bioconversion energy) 06/01781 Inclusion of the specular component in the assessment of bidirectional distribution functions based on digital imaging Andersen, M, and Scartezzini, J.-L. Solar Energy, 2005, 79, (2), 159167. To describe complex fenestration systems such as novel solar blinds, new glazing or coating materials, daylight and sunlight-redirecting devices, a detailed description of their optical properties is needed, given by their bidirectional transmission (or reflection) distribution functions (commonly named BTDFs and BRDFs). These functions are angle-dependent at both the incidence and the emission levels, and are defined as the ratio of the luminance of a surface element in a given direction (after diffuse transmission or reflection) to the illuminance on the sample. However, these functions are capable of describing the specular as well as the diffuse components of emerging light, and their mutual knowledge is necessary to properly assess a glazing or shading system's daylighting performances and benefit from their potential as energy-efficient and users' comfort strategies. Although the analytical expression of a BT(R)DF differs whether it is related to specular or diffuse light, a simultaneous assessment of the two components can be achieved under certain conditions. These conditions are analysed for the particular data acquisition procedure developed for a novel type of bidirectional goniophotometer, based on digital imaging.BRDFs)

06/01782 Preparation of highly porous silica nanocomposites from clay mineral: a new approach using pillaring method combined with selective leaching Ishii, R. el al. Mieroporous and Mesoporous Materials, 2005, 79, (1 3), 111-119. A silica xerogel was synthesized from a clay mineral by a new approach using a pillaring method combined with a selective leaching method. Preparation was conducted by applying an HC1/ethanol treatment after intercalation and condensation of tetraethoxysilane (TEOS) and/or methyltriethoxysilane (MTS) into cetyltrimethylammonium (CTA) ionexchanged vermiculite. The products are porous nanocomposites consisting of TEOS and/or MTS-derived polysiloxane and hydrated silica, resulting from the selective leaching process of the inorganic constituents and the extraction of CTA ions from CTA-exchanged vermiculite after the intercalation of TEOS and/or MTS. The morphology remains similar to the originated vermiculite owing to the topotactic dissolution process. The products have high porosity with 1205-715 m e g ~ of BET surface area when prepared with up to 2 tool dm -3 HC1 concentration. The pore size distributions of the products show a wide distribution from 1 nm to 4 n m in diameter due to the presence of micropores and mesopores. The HC1 concentration dependence of the surface area suggests that the main porosity arises from the porous polysiloxane which is formed by the pillaring process. Water adsorption isotherms reveal that the products have a hydrophilie surface originating from silanol groups on the polysiloxane and the hydrated silica. However, the incorporation of MTS in the pillaring process results in successful surface modification of the products. This novel approach is advantageous for the synthesis of highly porous xerogels with different kinds of surface properties.

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06/01785 Study of gamma-radiation-induced optical effects in Ge-Se-Cd for possible industrial dosimetric applications Amin, G. A. A. and Spyrou, N. M. Radiation Physics and Chemistry, 2005, 72, (4), 419 422. The effect of 6°Co "y-irradiation on the optical properties of the amorphous chalcogenide semiconductor, Ge14Se71Cd15 is studied. 7radiation-induced darkening is observed after irradiation of the thin film samples for doses up to 500 kGy. The changes in the optical absorption coefficient have been attributed to the amorphous network rearrangements and the degree of disorder caused by the -~-irradiation. The dosimetric characteristics of Ge'~14SeyaCd15 for "~-irradiation measurements are proposed. The absorption coefficient was found to increase with the increase of dose in a nearly linear manner. The optical energy gap was found to decrease with the increasing dose. The values of the absorption coefficient in the absorption edge region are suitable control parameters of the proposed dosimeter material, which is characterized by the sensitivity and reproducibility of measurements. The proposed dosimeter material has a minimum detectable effect at a dose of 100 kGy. This makes the material a good candidate for dosimetry in high-dose industrial applications such as sterilization.

06/01786 Temperature dependence of the optical band gap and refractive index of poly(ethylene terepthalate) oligomerDDQ complex thin film Yakuphanoglu, F. et al. Solar Energy, 2005, 79, (1), 96 100. The temperature dependence of the optical band gap and refractive index dispersion of thin film of poly(ethylene terepthalate) oligomerD D Q charge transfer complex has been investigated. The absorption edge shifts to the lower energy as consequence of the thermal annealing on film and the fundamental absorption edge corresponds to a direct energy gap. The temperature coefficient of the optical band gap for the film was found as dEg/dT = 3.15 x 10-3 eV/K. The temperature dependence of the refractive index has also been investigated and it is observed that the refractive index changes by annealing temperatures.

Radiant cooling of an enclosure

Chebihi, A. et al. Energy Conrersion and Management, 2006, 47, (3), 229-252. The purpose of this study is to analyse the potential for radiant cooling using the atmospheric sky window and to evaluate the desired characteristics of a radiant cooling material (RCM) applied to the ceiling window of a three-dimensional enclosure. The thermal characteristics of the system are governed by the geometry, ambient temperature, sky radiative temperature, amount of solar energy and its direction, heat transfer modes, wall radiative properties, and radiative properties of the RCMs. A semi-grey band analysis is utilized for the solar and infrared bands. The radiosity/irradiation method is used in each band to evaluate the radiant exchanges in the enclosure, The radiative properties for the R C M are varied in a parametric study to identify the desired properties of RCMs. For performance simulation of real RCMs, the radiative properties are calculated fi'om spectral data. The desired solar property is a high reflectance for both opaque and semi-transparent RCMs. For a semi-transparent RCM, a low value of the solar transmittance is preferred. The desired infrared property is a high emittance for an opaque RCM. For a semi-transparent RCM, a high infrared transmittance is desired, and the emittance should be greater than zero.

06•01784 Smart glazing solutions to glare and solar gain: a 'sick building' case study James, P. A. B. and Bahai, A. S. Energy and Buildings, 2005, 37, (10), 1058-1067. Holographic optical elements (HOE) can provide solar control by reflecting/redirecting the beam (direct) radiation incident on a window. This paper considers H O E applied for solar control in an office development at Southampton University, UK. In 2000, a new

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University campus was constructed through the renovation of existing Victorian school buildings coupled to modern, highly glazed office extensions. However, the combination of the low thermal mass of the extensions and the high level of glazing led to excessive office temperatures and occupant discomfort. Office users requested the installation of individual air conditioning units, which would represent an unacceptable indicator of the building's design failings. Simulation of the office structure has been undertaken using transient thermal analysis to model possible solutions. Forced air convection, louver systems and facade changes such as electro-chromic glazing are considered in addition to solar control holograms. The simulations highlight the need for the elimination of solar glare within offices and for some form of control of artificial lighting within the building. It is predicted that H O E can produce a comfortable working environment while maintaining daylighting and external views from the office: a combination of benefits which competing technologies such as blinds cannot provide.

Fuel and Energy Abstracts July 2006

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ALTERNATIVE ENERGY SUPPLIES Biofuels and bioconversion energy

06/01787 Amount, availability, and potential use of rice straw (agricultural residue) biomass as an energy resource in Japan Matsumura, Y. et al. Biomass and Bioenergy, 2005, 29, (5), 347-354. This paper discusses the use of agricultural residue in Japan as an energy resource, based on the amounts produced and availability. The main agricultural residues in Japan are rice straw and rice husk. Based on a scenario where these residues are collected as is the rice product, the size, cost, and CO2 emission for power generation were evaluated. Rice residue has a production potential of 12 Mt-dry year -1, and 1,7 kt of rice straw is collected for each storage location. As this is too small an amount even for the smallest scale of power plant available, 2month operation per year is assumed. Assuming a steam boiler and turbine with an efficiency of 7%, power generation from rice straw biomass can supply 3.8 billion(kW)h of electricity per year, or 0.47% of the total electricity demand in Japan. The electricity generated from this source costs as much as 25 JPY (kW h) -1 (0.21 US$ (kW h) -1, 1