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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.solener.2009.10.018 Byline: Ho Chang (a), Hung-Ting Su (b), Wei-An Chen (a), K. David Huang (c), Shu-Hua Chien (d), Sih-Li Chen (b), Chih-Chieh Chen (e) Keywords: Electrophoresis deposition (EPD); TiO.sub.2 film; Photoelectrode; Energy conversion efficiency Abstract: This research coats a commercial TiO.sub.2 nanoparticle Degussa P25 with good roundness and size uniformity on an indium tin oxide (ITO) glass substrate and to be photoelectrical electrode by electrophoresis deposition. It combined with dye N719, electrolyte I.sup.-/ I.sub.3.sup.- and counter-electrode of Pt layer to produce dye-sensitized solar cells (DSSCs). Through the electrophoretic technique, a multilayer film of an appropriate thickness is deposited in the suspension containing TiO.sub.2 nanoparticles and isopropanol. In this process, electric current, voltage, and the number of deposition cycles are well controlled to obtain a single TiO.sub.2 film of around 3.3[mu]m thick. Stacking is then performed to obtain a multilayer-typed TiO.sub.2 film of around 12[mu]m thick. As the sintering temperature reaches 400[degrees]C, the prepared multilayer TiO.sub.2 film with a good compactness can increase the dye adsorption capability of the thin film and enhance its adsorption percentage. In addition, the heat treatment will transfer a portion of the rutile crystalline into the anatase crystalline, resulting in better material properties for DSSCs application. DSSCs produced are exposed to metal halide lamp and their energy conversion efficiency is measured. The I-V curve of the produced DSSCs shows that it has an excellent energy conversion efficiency of 6.9%. Author Affiliation: (a) Department of Mechanical Engineering, National Taipei University of Technology, Taiwan (b) Department of Mechanical Engineering, National Taiwan University, Taiwan (c) Department of Vehicle Engineering, National Taipei University of Technology, Taiwan (d) Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan (e) Department of Mechanical and Mechatronic Engineering, National Taiwan Ocean University, Taiwan Article History: Received 6 June 2009; Revised 20 October 2009; Accepted 23 October 2009 Article Note: (miscellaneous) Communicated by: Associate Editor Sam-Shajin Sun

This article experimentally studies the thermal performance of latent heat storage in a two-phase thermosyphon solar water heater, which utilizes the superior heat transfer characteristics of boiling and condensation, and eliminates drawbacks found in the conventional solar water heater. Experimental investigations are first conducted to study the thermal behavior of tricosane (paraffin wax 116), water, and sodium acetate (NaC[H.sub.3]COO x 3[H.sub.2]O) used as energy storage materials. The results indicate that tricosane provides many advantages to be the energy storage material in the latent heat storage system. This study also examines the functions of charge and discharge thermal behaviors in a two-phase thermosyphon solar water heater The results show that the system gives optimum charge and discharge performance under 40% alcohol fill ratio and with tricosane used as the energy storage material, and displays an optimum charge efficiency of 73% and optimum discharge efficiency of 81%. [DOI: 10.1115/1.2147588] Keywords: energy storage material, two-phase thermosyphon, solar water heater

This article presents an energy storage system, which can be readily integrated with the building structure. It stores heat supplied by solar energy via the two-phase closed loop thermosyphon to storage tank and releases stored heat in energy storage material via two-phase closed thermosyphon to the heat exchanger through the flow of transport fluid. The functions of such energy storage system have three operating modes, i.e., heat charge, heat discharge, and simultaneous charge and discharge. The thermal performance of the system with alcohol and water as working fluid is experimentally investigated. The results show that the storage system employing alcohol as working fluid in the loop thermosyphon provides better performance; the system gives optimum heat charge and discharge performance under 35-40% fill ratio, regardless whether the working fluid is water or alcohol. The system displays optimum charge efficiency of 73% and optimum discharge efficiency of 85% with alcohol as working fluid.

The application of mini-environment and standard mechanical interface (SMIF) enclosure in the clean room can efficiently reduce airborne particles and isolate the personnel from the product. The purpose of this article is to reduce the recirculation zone and to maintain the positive pressure from the analysis results of the airflow field and pressure distribution of SMIF enclosure and mini-environment. The simulation code CFX will be used to study the flow field of air movement corresponding to the associated design parameters. The results show that proper drilling holes or slots can reduce the circulation zones of SMIF enclosure. The positive pressure of SMIF enclosure is mainly affected by inlet air flux, area of outlets, and leakage area. The calculated results can provide the design rules for SMIF Robot inside the SMIF enclosure and reduce the particle accumulation during robot moving. Index Terms--Air cleanliness, air flow field, mini-environment, SMIF enclosure.