The effect of pesticides on farmers and the distribution of residual pesticides in rice plants and rice grain was studied in rice farming area covered in Samchuk district Suphanburi province. The situation and health effects related to pesticides was conducted using an individual interview and filled-form questionnaire with 126 samples. The participants were male of 68.3% and female of 31.7%. Educational level of participants was to be 36.5% and 24.6% for primary and elementary levels respectively. One-third of farmers (33.3%) reported a monthly income in the range of 5000 to 10000 Baht. A quarter of farmers (25.4%) got higher a monthly income with 10001 to 15000 Baht. Family members was found to be 4 persons (54%) 5 persons (19.8%) and over 5 persons (11.1%). All participants concerned the behavior and perception related pesticides for their highly toxicities and extremely dangerously death. A half of herbicide (50%) was glyphosate. Seriously paraquat (commercial name of Gramoxone) was found to be 22%. On the other hand the most of insecticide (55%) was an abamectin and carbofuran (commercial name of Furadan) was found to be 15%. A 20 samples of rice plants and rice grain was collected by random sampling. The residual carbofuran and glyphosate in rice plants and rice grain was determined using standard method. It was found that carbofuran was found in the range of ND-0.05 μg/kg and ND-0.08 μg/kg for rice plants and rice grain respectively. Glyphosate was found in the range of ND-0.26 μg/ kg and ND– 0 . 2 2 μg/ kg for rice plants and rice grain respectively. The residual levels of carbofuran and glyphosate in rice plants and rice grain depended on a spray period time their decomposition and the concentration of carbofuran and glyphosate. The residual levels of carbofuran and glyphosate did not significantly quantitative correlation between rice plants and rice grain.

The objective of this research is to study the dispersion of copper oxide particles in water using as a coolant in heat exchangers. Copper oxide particles were prepared by precipitate method. The parameters affected to dispersion of copper oxide were pH of solution and ultrasonic time. The results showed that an average crystalline size of copper oxide was in nano scale (< 22 nm). At pH value of 13 copper oxide was well dispersion in the water. Appropriate ultrasonic time of dispersion is dependent on particle sizes of copper oxide. The small particle sizes of copper oxide led to decreasing of ultrasonic time. On the other hand an increasing in particles sizes required longer ultrasonic time. Stability of suspension of CuO in the water decreased with an increasing of time. Moreover it was found that CuO particles were well dispersed in the water at pH value of 13 and ultrasonic time of 15 minutes