Earticle

In this study, the method was developed to measure BTEXs exposure level in the air as well as their metabolites of benzene and toluene via human urine and genetic polymorphisms in human blood for evaluation of the health effects about environmental pollution. We have also performed a small-scaled molecular epidemiology study on suburban residents in Chuncheon, industrial residents in Ulsan and workers in workplace for these method applications.

Overall adsorption rate was compared to investigate the adsorption characteristics of dye acid-blue 92 with pH and temperature, where was performed by a differential bed reactor with TiO2 of 3.3 g. Overall adsorption rate of a dye acid-blue 92 on titanium dioxide was described as following equation. r=k1Ce9.4-k2qe5.4 In the range from pH 2 to pH 12, value of klof the dye acid-blue 92 decreased from 0.84 to 0.05 but k2 increased from 0.08 to 0.39 with an increasing pH. Removal rate of a dye was described as an apparent first order and rate constant as the highest at pH 2 and decreased with an increasing pH. With an increasing temperature from 20 to 50 ˚C. both values of kl and k2 increased from 0.75 to 0.97 and from 0.10 to 0.15, respectively. and removal rate constant, k, increased, too.

PHI3 productivities by Alcaligenes eutrophus from glucose, lactose, and whey were estimated by batch fermentations. From the fermentation of whey without pH control in Alcaligenes eutrophus, maximum conversion into PHB was 52.0%, where those by glucose and lactose were 75.0% and 53.0%, respectively. Carbon utilization rates were 90.0, 96.0, and 89.0% for whey, glucose, and lactose, respectively, at the final stage of fermentation in 45 h. When pH was controlled at optimal values of 7.2~7.3 during the fermentation, the yield of PHB could be obtained higher by about 6.0~7.0 % than without pH control. Though PHB yield by wasted whey was lower than those of glucose and lactose, since whey was cheaper by about 70% than glucose and lactose, the economic efficiency of PHB production by waste whey was estimated as higher than those by glucose and lactose.

The purpose of this study is to understand the characteristics of total volatile organic compounds (TVOCs) emission from furniture materials through the small chamber test method. Particle board and medium density fiberboard as wood products, synthetic leather and textile were selected for this study. The TVOCs concentrations of each test material increased to maximum value in 1-3 days and rapidly decreased in 27 days. The unidentifiable VOCs occupied over 70% of the TVOCs concentration. Toluene occupied the greatest proportion of the identifiable VOCs and benzene, 1,2,4-trimethylbenzene and xylene occupied relatively high proportion of the identifiable VOCs for all test materials. A first-order decay source model in explicit chamber model was used to evaluate the characteristics of TVOCs emission from these furniture materials. Synthetic leather showed the highest initial emission factor and textile had the lowest initial emission factor for TVOCs among tested materials. Also, synthetic leather had the highest emission decay constant and particle board had the lowest emission decay constant for TVOCs.

The purpose of this study is to understand the characteristics of formaldehyde emission from furniture materials through the small chamber test method. Particle board and medium density fiberboard as wood products, synthetic leather and textile were selected for this study. The formaldehyde concentrations of each test material increased to maximum value in 1-3 days and rapidly decreased in 27 days. A first-order decay source model in explicit chamber model was used to evaluate the characteristics of formaldehyde emission from these furniture materials. Medium density fiberboard showed the maximum value of initial emission factor and synthetic leather showed the minimum value of initial emission factor for formaldehyde. Also, Synthetic leather showed the highest emission decay constant and medium density fiberboard showed the lowest emission decay constant for formaldehyde. These emission parameters were used in estimation of indoor concentration of carcinogens such as formaldehyde in an imaginary residence equipped with furniture made of tested materials.