A portable current meter for accurate current speed measurement and suitable for use by an individual in natural streams was devised. The meter consists of a sensor with a four-bladed propeller (30 mm diameter), a photo coupler and a counting apparatus (a modification of the 3631 rotation meter: Yokogawa Hokushin Electric). A high accuracy of calibrations was obtained under laboratory conditions, and its reliability and operability were also tested at a natural stream .

This work demonstrates how to develop a qualitative surface reaction model to an elementary surface reaction simulation of deposition for the quantitative examination of model validity. Chemical vapor deposition of Al (Al-CVD) from dimethylaluminumhydride (DMAH) is examined as an example of this method. The surface reaction model of DMAH was deduced from ab initio cluster model calculations and experimental measurements of reaction products. Rate constants of all the elementary reactions were estimated for an elementary reaction model. Transition-state theory enabled the calculation of rate constants using the activation energies obtained from ab initio calculations. Entropy terms, however, were estimated by using an empirical method to reduce the computational effort. This approach minimized the ab initio calculations required to form a reaction data set. Simulated deposition profiles were compared with experimental data for Al-CVD in a tube reactor. Good agreement between the results of simulations and experiments indicate the possibility of constructing surface-reaction data sets for CVD process simulations based on ab initio quantum-chemical calculations.

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The photoreduction of ethylenediaminetetraacetato cobaltate(ii1) ([Co(edta)] -) by 1 -benzyl-I ,4dihydronicotinamide (BNAH) has been studied in the presence of the surfactants cationic dodecyltrimethylammonium chloride (DTAC) and anionic sodium dodecylsulphate (SDS). Cationic DTAC accelerates the photoreduction of [Co(edta)] -, while anionic SDS suppresses the reaction. The micellar effects on the reaction rates have been analysed by distribution of the reactants between an aqueous phase and a micellar phase and monitoring the difference in rate. In the DTAC micellar system, cationic micelles promote the reaction significantly by concentrating the photoexcited BNAH and [Co(edta)] -through hydrophobic and electrostatic interactions in spite of the smaller rate constant in the micellar phase compared with that in the aqueous phase. On the other hand, anionic SDS hinders approach of the anionic [Co(edta)]to the photoexcited BNAH in the SDS micelles, so as to retard the reaction rate.

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