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In this study, nano-sized barium titanate powder was applied for the first time to polyester woven fabrics by knife coating at three different concentration rates. Some physical (thickness, mass per unit area, bending rigidity, air permeability and tear strength) properties, electromagnetic shielding efficiency and solar (transmittance, reflectance) properties of samples were presented. The samples were also characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. Electromagnetic shielding effectiveness of the fabrics was determined according to the ASTM D4935-10 standard by using a coaxial transmission line measurement technique in the frequency range of 15–3000 MHz. The solar properties were measured according to EN14500 standard using a UV/VIS/NIR spectrophotometer and results were calculated according to EN 410 standard. Results revealed that the electromagnetic shielding effectiveness and solar reflectance property of samples improved with increasing barium titanate concentration. [ABSTRACT FROM AUTHOR]

Abstract C-axis textured thin films of gallium-doped indium zinc oxide (GIZO) with a 2% ratio of Ga/Zn, were obtained via RF-magnetron sputtering with high transparency and electrical conductivity. A Box-Behnken response surface design was used to evaluate the effects of the deposition parameters (In 2 O 3 target power, deposition time, and substrate temperature) on the chemical composition, optical, electrical, and structural properties of the GIZO films. The optical constants and the electrical properties were obtained using optical models. The GIZO stoichiometry, and therefore the In/Zn atomic ratio, affected the crystallinity, crystalline parameters, band gap, and charge carrier mobility of the GIZO films. The charge carrier density was related to the change in the crystalline parameters of the hexagonal structure and the In/Zn atomic ratio. The best electrical conductivity values (1.75 × 103 Ω−1 cm−1) were obtained for GIZO films with In/Zn ratio ≥ 1. Several figures of merit (FOM) defined for the visible and solar regions were comparatively used to select the optimal In/Zn atomic ratio that provided the best balance between the conductivity and the transparency. The optimal In/Zn ratio was in a range of 0.85–0.90 for the GIZO films. Graphical abstract fx1 Highlights • A Box-Behnken experimental design was used in this study. • The relationship between GIZO stoichiometry and the film properties were established. • New figures of merit were proposed for the visible and solar regions. • In/Zn ratio for a good compromise between conductivity and transparency was found. [ABSTRACT FROM AUTHOR]

Highlights • Thermal response of roof/wall was analysed by altering U value and solar properties. • Solar absorptivity has significant effect on total energy use, especially at U > 0.3. • Optimal total energy use in Hamburg and Granada was always achieved by cool coating. • Coating's solar properties affect indoor thermal comfort in summer and winter. Abstract In recent decades, high level of urbanization, air pollution and climate change have caused a frequent occurrence of urban heat islands, resulting in thermal discomfort and increased energy use of buildings. As a response, a lot of attention has been paid to building envelope characteristics, with an increasing number of studies investigating building envelope solar properties as one of the important factors affecting thermal performance. However, different climate characteristics are the reason why solar properties may have different efficiency at various locations, also because in cold or temperate climates building envelope has to be more thermally insulated, namely having lower thermal transmittance. Therefore, within this study, building energy use and indoor thermal conditions were analysed for an office cell using different types of solar absorptivity (e.g. white, dark grey, collector or cool coating) and thermal transmittance, on either external wall or roof. The analysis was conducted for hot-arid and temperate climate locations. The results showed that solar absorptivity can have a significant effect on total energy use, especially in cases with higher envelope thermal transmittance. It also showed that the application of cool coatings is more reasonable if the external building envelope is not intensively thermally insulated (e.g. in hot-arid climate). In general, the optimal total energy use in both analysed climates was always achieved by implementing cool coatings. Furthermore, the results showed that white and cool coatings have comparable external (20–30 K above T air in summer) and internal surface temperature responses, while dark grey coatings cause the surface to heat up significantly (external surface 60 K above T air in summer). [ABSTRACT FROM AUTHOR]

The effects of the Cu x S stoichiometry, 1 ≤ x ≤ 2 , on the optical, electrical, and solar thermal properties of copper sulphide thin films, which have been deposited by chemical spray pyrolysis onto glass, have been studied. A full 3 2 factorial design has been applied to determine the effects of the substrate temperature and deposition time on the electrical and optical properties of the sulphide thin films. The sulphide film properties are strongly related to the Cu x S stoichiometry, and this relationship is dependent on the substrate temperature. Therefore, the electrical resistivity of the films varies in the range of 10 −4 Ω cm to 10 −1 Ω cm as × increases from 1 to 2. The relationship between the stoichiometry and conductivity has been established with infrared reflectance, solar absorptance and thermal emittance. The optical constants have been obtained using optical models (Classical Drude). [ABSTRACT FROM AUTHOR]

Neutron and mixed gamma and neutron irradiation, at different absorbed doses, of borosilicate glass with four different chemical compositions was conducted to investigate the effects on the solar properties of the glass. Irradiation was performed in the tangential beam tube and central thimble of a nuclear reactor. The effect of thermal and epithermal neutrons on such solar properties as secondary heat-transfer factor, solar factor (the total solar energy transmittance), and shading coefficient of the borosilicate glass were investigated to determine the effect on the solar properties of borosilicate glass, because of its neutron absorbance property. [ABSTRACT FROM AUTHOR]

Abstract: WO3 films were prepared by sol–gel deposition process on Corning 2947, microscope slide substrates. The effects of irradiation on the solar parameters of WO3 films were investigated between ∼1 and 21kGy absorbed dose by Co-60 radioisotope. Three characteristic optical density bands explained the causes of color due to the absorption of sunlight at induced color centers of the transition elements such as W, Fe and Zr after the gamma irradiation. These bands lead to variations on the solar control in terms of shading coefficient. The absorbed dose plays a key role in the improvement of the shading coefficient dramatically, hence the solar parameters changed considerably depending on the induced color centers of the transition elements and the variations of the grains and the void sizes of the film. The results of the solar parameters of irradiated WO3 films were compared with the unirradiated WO3 films and uncoated corning in the solar range. [Copyright &y& Elsevier]

Purpose: To study the dosimetric characteristics of a commercial three-dimensional water scanner (3D SCANNER, Sun Nuclear Corp). The novel cylindrical scanner uses a compact electrometer mounted on the side of the tank, eliminating the need for chamber extension cables. The electrometer has a wide dynamic range, requiring no gain adjustment as scanning conditions change, e.g., field size, dose rate, wedge field, etc., Methods: Measurements from the 3D SCANNER were compared against those from another commercial scanner (Blue Phantom, IBA Dosimetry). Comparable collection intervals and scanning speeds were used on both systems. Profile and depth measurements were performed for open field beams (6 and 18 MV; 10-cm and 30-cm squared fields; depths of dmax, 10, and 30 cm) and wedged fields (6 and 18 MV; 30-cm squared field; depth of 10 cm). Electron beam profile and depth measurements were performed for a 20-cm squared applicator (6, 12, and 20 MeV; depth of dmax). The root mean square (RMS) values were determined for each scanner's measurements., Results: The measured field sizes were within 0.06 cm and 0.05 cm for photon and electron beams, respectively. The photon D10/D20 ratios differed by < 0.4% and the electron I50 values were within 0.02 cm. The RMS of the profiles was approximately 0.1% for both the 3D SCANNER and Blue Phantom measurements. Between the two scanners, all measurements agreed within RMS, excluding the penumbra region. Two exceptions occurred: a 0.5% difference was observed in the shoulder of the 12 MeV profiles, and a 0.8% difference was observed in the 6 MeV depth measurements near the surface., Conclusions: The quality of the scanned profile and depth measurements from the 3D SCANNER is comparable to that of another commercial scanner. Both scanning systems have similar levels of scanning noise. This work was partially supported by a research grant from Sun Nuclear Corp., Melbourne, FL., (© 2012 American Association of Physicists in Medicine.)

Purpose: Quality assurance (QA) is essential in safe and accurate delivery of radiation therapy. However, QA in proton therapy is challenging due to complicated and often facility-specific beam delivery systems and limited beam time for QA. The purpose of this study is to develop an efficient and comprehensive QA procedure for a multi-room proton therapy center using uniform scanning beams., Methods: Our proton therapy center is comprised of a 230 MeV cyclotron, one fixed beam room, two inclined beam rooms, and one gantry room. Uniform scanning is employed exclusively in all treatment rooms. A rfDaily QA3 (Sun Nuclear Inc., Melbourne, Florida) together with home-made devices is used for daily QA. Parallel plane chambers, a multi-layer ionization chamber array (Zebra, IBA dosimetry, Schwarzenbruck, German), and an IC profiler (Sun Nuclear Inc., Melbourne, Florida) are used to QA the characteristics of the uniform scanning beams, including output, range, modulation width, flatness, symmetry, and penumbra, for both monthly and annual QA. QA procedures and acceptance criteria were developed, taking into account the likelihood and potential risk of failure, as well as the available equipment, personnel and other resources., Results: QA procedures and tolerances were developed for daily, monthly and annual QA at our proton therapy center. Daily QA is performed by radiation therapists, and can be completed within 30 minutes for all rooms. Monthly QA and annual QA are performed by physicists, taking about 4 hours and a weekend respectively. Trend analysis was performed for various machine characteristics, such as machine output, range, flatness, and symmetry., Conclusion: QA standards are desired in Radiation Oncology, but not many standards are developed and available for proton therapy. In the mean time, facility-specific QA procedures should be developed based on the equipment failure modes and available resources., (© 2012 American Association of Physicists in Medicine.)