Ultra-thin films are grown on the Mo(100) surface using evaporated Ti metal under ambient pressure. The thickness of the film is controlled by the dosing rate of Ti metal over Mo(100) which is determined from the Auger signal changes with dosing time. 30 ML, 5 ML, and 1.6 ML thick films are prepared and used to determine the growth mechanism, the chemical composition, and the surface structure of the films. The growth mechanism of the film on Mo(100) is observed to follow the layer-by-layer growth mechanism. The chemical composition of the film is found to be that of bulk . The surface plane of the film is (001), which facets irreversibly at 1200 K. The LEED pattern obtained from the film can be explained with the faceted surface with {011} planes reconstructed to with respect to the (001) surface. The film is somewhat thermally unstable when annealed to 1300 K. The film sputtered with ion is also studied by XPS.

The photochemical reaction of ammonia in deoxygenated aqueous methanol has been investigated at 25 using 184.9 nm UV light. Amination was carried out by irradiating the solution of reaction mixture, and the formation of methoxyamine, hexamine, 1,1-dimethylhydrazine, dimethylamine, formamide, and a small amount of ethylenediamine was observed. In addition to these, carbonyl compounds such as formaldehyde, ethyleneglycol, glyoxal, and hydrazine were also produced. The initial quantum yields of the products were determined and probable mechanisms for the photochemical reaction were presented on the basis of product analysis.

The sorption kinetic was studied to evaluate feasibility of removing PCBs from mineral oil with activated carbon. Adsorption efficiency for Aroclor 1242 which is composed of lower chlorinated PCB formulations was 95%, whereas the adsorption efficiency for Aroclor 1260 having higher chlorinated constituents was considerably lower with the efficiency falling to 75%. The observed difference in the adsorption efficiency is attributed to the geometry of PCBs with non-planar and coplanar structure. The concentration of coplanar PCBs is appreciably higher in Aroclor 1242. Since toxicity is primarily associated with coplanar congeners, the preferential adsorption of coplanar congeners by activated carbon accounts for the fact that toxicity reduction can be achieved through this process. The efficiency of process was assessed in terms of Toxicity Equivalence Factor (TEF).ᔌ툀؀㌸㜮ㄻԀ䭃䑎䷗ᜓ૚5〰㬅K䍄乍

In the presence of optimum amounts of hydroxylamine, trace ruthenium(III) can be conveniently determined in acidic (boric) media by coupling catalytic hydrogen processes with adsorptive accumulation of the catalyst, using differential pulse voltammetry. Cyclic voltammetry was used to characterize the redox and interfacial processes. Optimal experimental conditions were found to be a stirred borate (0.015 M, pH 2.5) solution containing 0.55 M hydroxylamine, a preconcentration potential of - 0.70 V, and a scan rate of 5 mV/s. With a 7 min accumulation period the detection limit was 310-10 M. The possible interferences by other platinum group metals are investigated.

Fluorescence spectra and life time of ion in borosilicate glass medium are measured. Electronic transitions of ion in borosilicate glass medium are found to come from (J=0, 1, 2, 3, 4) transitions of SL coupling system in electrons configuration. From the number of Stark sublevels in spetra, crystal field for ion is also found to have the symmetric character of low symmetry order, . The fraction and the number of components of life times were varied depending on the composition of in borosilicate glasses, from which the binding condition between the ion and anionic oxygen of borosilicate glass can be deduced.‍씀܀㘲ㄮ㠹㬏A灰汩敳⁰桹獩捳

A rapid and sequential method was studied, which can determine nitrite, nitrate and ammonium ion in soil or water samples with flow injection analysis. Geometric factors including injection volume, length of the reaction coil and flow rate of carrier solution were investigated prior to sample measurement. Nitrite was determined at 540 nm by Griess reaction producing azo dye between N-(1-naphthylethylenediamine dihydrochloride) and sulfanilamide. Nitrate was also measured under the help of reduction mechanism toward nitrite with hydrazine. Ammonium was analyzed at 440 nm with Nessler's reagent. At the optimum condition, the detection limit(S/N=3) has been shown 0.1 ㎍/mL N(NO2-), 0.4 ㎍/mL N(NO3-) and 0.3 ㎍/mL N(NH4+) respectively. The results measured by colorimetry, ion chromatography and FIA were compared showing 80%-125% reasonable match each other. Injection throughput rate could be performed better than 30 times per hour.ᬊ吀Ѐ㘷〻ഀ䵡湵晡捴畲楮最