Y 1.86 Eu 0.14 WO 6 phosphors were prepared using a solid-state reaction method. Their optical properties were analysed, and they was mixed with TiO 2 , sintered, and used as a photoelectrode (PE) in dye-sensitized solar cells (DSSCs). The as-prepared photoelectrode was characterized by photoluminescence spectroscopy, diffuse reflectance, electrochemical impedance spectroscopy (EIS) and X-ray diffraction. The photoelectric conversion efficiency of the DSSC with TiO 2 :Y 1.86 Eu 0.14 WO 6 (100:2.5) was 25.8% higher than that of a DSCC using pure TiO 2 as PE. This high efficiency is due to the ability of the luminescent material to convert ultraviolet radiation from the sun to visible radiation, thus improving the solar light harvesting of the DSSC.

Photothermal Deflection Spectroscopy (PDS) technique was used to study undoped and copper (Cu) doped cadmium sulphide (CdS) thin films. Variation in grain size and lattice strain due to Cu doping were analysed using X-ray diffraction (XRD). Changes in mobility of carriers in CdS with Cu concentration was studied using PDS technique for the first time and results are compared with the earlier ones. Thickness of Cu diffused region in CdS was also calculated and compared with results from X-Ray Photoelectron Spectroscopy (XPS) and Ellipsometry. Results from PDS technique are found to be agreeing with those from other experiments. (c) 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

ZnO and In2S3 thin films useful for photovoltaic application were studied using Photothermal deflection (PTD) spectroscopy. Mobility of carriers obtained from PTD was found to be in good agreement with reported values. Thickness measurements were also carried out. It was found to be in good agreement with stylus method.

Photothermal deflection spectroscopic technique was used to study Ar+ implanted cadmium sulphide thin films. Variations in grain size and lattice strain due to Ar+ irradiation were analysed using X-ray diffraction. Thickness of damaged layer in CdS due to Ar+ implantation was calculated using photothermal deflection technique and compared with results from Stopping and Range of Ions in Matter.

Although liquid lead-bismuth eutectic (LBE) is a good candidate for coolant in the subcritical transmutation blanket, it is known to be corrosive to stainless steel, the material of the carrying tubes and containers. Such long- term corrosion problem can be prevented by producing and maintaining a protective oxide layer on the exposed surface of stainless steel. For this purpose, it is required to accurately control the concentration of oxygen dissolved in LBE. Currently, YSZ (Yttria Stabilized Zirconia) oxygen sensors, based on an existing automotive oxygen sensor, with molten bismuth saturated with oxygen as the reference, have been selected for oxygen-concentration measurement. The oxygen concentration difference across the solid electrolyte and the resultant oxygen ion conduction inside the electrolyte establishes an electromagnetic force that is used to measure the ppb level concentration of oxygen dissolved in liquid LBE. A set of calibration curves of voltage vs. temperature ranging from 300 0C to 500 0C under various oxygen concentrations in liquid LBE for the YSZ oxygen sensor has been obtained and is presented in this paper. Although the current calibration strategy using the direct injection of hydrogen and oxygen is still inadequate to determine the oxygen concentration in the system, we have found a good candidate for our purpose, which is varying hydrogen to water steam ratio in the system.

The photochemical reactions of methylene blue in gelatin and polyvinyl alcohol matrices due to He-Ne laser exposure are investigated. Laser irradiation results in the formation of a new absorption peak which matches with that of thionine. Retention of this optical absorption change due to irradiation for several months is observed. The present study confirms that on irradiation some irreversible changes are also occurring in methylene blue in addition to the reversible change to leuco methylene blue. Possibility of permanent recording is suggested.

Although liquid lead-bismuth eutectic (LBE) is a good candidate for coolant in the subcritical transmutation blanket, it is known to be corrosive to stainless steel, the material of the carrying tubes and containers. Such longterm corrosion problem can be prevented by producing and maintaining a protective oxide layer on the exposed surface of stainless steel. For this purpose, it is required to accurately control the concentration of oxygen dissolved in LBE. Currently, YSZ (Yttria Stabilized Zirconia) oxygen sensors, based on an existing automotive oxygen sensor, with molten bismuth saturated with oxygen as the reference, have been selected for oxygen-concentration measurement. The oxygen concentration difference across the solid electrolyte and the resultant oxygen ion conduction inside the electrolyte establishes an electromagnetic force that is used to measure the ppb level concentration of oxygen dissolved in liquid LBE. A set of calibration curves of voltage vs. temperature ranging from 300 C to 500 C under various oxygen concentrations in liquid LBE for the YSZ oxygen sensor has been obtained and is presented in this paper. Although the current calibration strategy using the direct injection of hydrogen and oxygen is still inadequate to determine the oxygen concentration in the system, we have found a good candidate for our purpose, which is varying hydrogen to water steam ratio in the system.