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The objective of this study is to examine the ability of a compost material for removing {Cu}^{2+} from aqueous solutions with different parameters using continuous fixed-bed column. Compost was characterized by using Fourier transform infrared spectroscopy which revealed that the metal binding is mainly contributed to the ionic interaction of the metal cations with the carboxyl groups in the hemic substances. Scanning electron microscope images were utilized for morphological analysis of the adsorbent and has revealed that the changes in compost composition could be related to the mechanism of metal binding. Energy dispersive X-ray spectroscopy was used before and after the metal had loaded and gives a good evidence on compost adsorption of {Cu}^{2+} and the metals have its involvement in the interaction in the adsorption process. The influence of the initial {Cu}^{2+}concentration, flow rate, bed heights of the column, and ion exchange have been studied in this research. The adsorption kinetic models have revealed that the behaviour of the {Cu}^{2+\ }adsorption is dependent on rate of concentration, flow rate, and bed heights.

Pesticide production and application have progressively increased worldwide during recent decades. Among these compounds, imidacloprid (IMD) is a widely used insecticide in agriculture, and more particularly to control sucking insects in crops. The aim of this work is to develop rapid, simple and sufficiently sensitive cyclic voltammetry (CV) and square wave voltammetry (SWV) for the detection and quantification of this insecticide in water and agriculture samples. Pretreated glassy carbon electrode (PGC) was employed as working electrode. Aqueous solutions were prepared with Confidor 200-SL commercial formulation of IMD. Each voltammogram was characterized by a well-defined single irreversible cathodic peak at approximately -1.38 V/SCE. The electrode reaction is mainly a diffusion controlled process. The optimization of experimental parameters such as IMD initial concentration, potential scan rate, pH and temperature was carried out by CV, and then a comparative study was conducted by SWV. For the detection and quantification of IMD, the results obtained by SWV showed higher sensibility and accuracy than that by CV. The developed methods were successfully used to determine IMD in real samples, namely plum and peach juice.

In this study, a new technology was introduced to monitor the odor occurrence situation at the remote site in real time and the technology to reduce sewage odor by using microbial deodorant. Long-term monitoring and full-scale test was carried out to investigate the odor concentration in the combined sewer using the real - time odor monitoring device which consist of 3 odor sensors with the wireless communication technique, and to investigate the effect of the microbial deodorant on the reduction of sewer odor. The odor monitoring device, which was fabricated using metal oxide semiconductor sensors and code division multi access communication technique, was installed at three sites of the gravity-flow type combined sewer (depth 3m and width 5m) in Gangnam, Seoul. Odor monitoring in field was carried out at the interval of 10 minutes for 304 days over the autumn, winter and summer. The measured results were transmitted to Woosong odor research center about 100km away from the site. The measured sensor value was converted to olfactory odor concentration by the co-relation equation of the sensor value and the olfactory odor concentration. As the monitoring results, more than 40,000 sewage odor data were obtained. The average odor concentration of raw sewage in combined sewer was 464 OUk, which was 321 OUk in winter and 412 OUk in autumn and 659 OUk in summer. The commercial microbial deodorant used in this study was the mixture culture of 48 microbial strains, and the microbial deodorant of 1 m3 d-1 to 2 m3 d-1 was mixed with raw sewage at the 1.5 km upstream of the site where odor complaints occurred. As the experimental results, the average odor concentration of sewage mixed with microbial deodorant was 113 OUk, which was 102 OUk in winter and 298 OUk in autumn and 153 OUk in summer. It was estimated that the odor reduction effect of sewer odor by microbial deodorant is about 74%.

For appropriate evaluation of environmental odours, it is necessary to develop a reliable odour measurement scale. Odour intensity reflects people’s perception of odours and contributes to effective odour management. In this study, Japanese conventional six-point odour intensity scale was reconsidered to ensure equal intervals between odour intensity levels. A new series of six dilution steps of 1-butanol solutions with a concentration of 0, 10, 600, 2600, 9000 and 22500 ppm (vol/vol) was proposed and explanatory labels for odour intensity levels were determined. In addition, polyethylene (PE) bottles were proposed as containers for 1-butanol odour intensity reference solutions for convenience in on-site handling, and the effectiveness of PE bottles was suggested. These results showed that the new odour intensity scale would be applicable to on-site investigations and practically useful for all people related to environmental odour evaluation.