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This study evaluated the feasibility of applying a visible-light-activated photocatalytic technique to cleanse air dimethyl disulphide (DMDS) at low concentration conditions (0.027-5.4 ppm), by using nitrogen-enhanced TiO2. In addition, the applicability of a backup adsorption unit for the secondary control of DMDS exiting from the photocatalytic oxidation (PCO) unit was investigated. The PCO unit functioned effectively for the control of DMDS at low concentration levels (or = 0.027 ppm) for long-time periods (at least 603 h). However, rapid photocatalyst deactivation levels were observed during photocatalytic processes with a higher DMDS input concentration (IC) (2.7 ppm). The photocatalyst reactivated with humidified or dried air, under visible-light irradiation, did not regain all its initial activities. The photocatalytic degradation efficiencies (PDEs) for DMDS were close to 100% for the relative humidity (RH) range of 45-55%, whereas they were between 86% and 91% and between 78% and 82% regarding the RH ranges of 10-20% and 80-90%, respectively. The PDEs via the PCO alone were close to 100% during this time period for the lowest IC conditions (0.027 ppm), whereas they decreased gradually for the other ICs. The FTIR spectra of the photocatalysts, as well as a solid-liquid extraction method, suggested the formation of sulphate groups on the catalyst surface during a photocatalytic process. Methanol was identified as a gaseous by-product. In addition, the backup adsorption unit could be effectively utilized to remove methanol, under a broad indoor pollution level (0.027-5.4 ppm), as well as DMDS exiting from the PCO units.

A study on fugitive dusts was conducted at Saemangeum reclaimed land and the neighboring farm located at the west coast of Korea. After the area was completely reclaimed in 2006, halophyte plants and several windbreak systems were installed. The distributions of suspended dust particle was regularly measured through field experiment. The size of dust source area was also analyzed periodically and then it was determined to be in the following order: Buan > Gimje > Gunsan. The suspended dust which were dispersed to the neighboring areas were significantly affected by the size of the soil particles, wind velocity and wind direction. The results of Big Spring Number Eight (BSNE) experiments also showed that the concentration of the fugitive dust generated from the reclaimed land was reduced remarkably by the presence of halophyte plants. Recently, in 2008, the measured dust concentration rate was decreased by an average of 30.6%. The average dust concentration is expected to decrease further as more areas are being covered by halophyte plants.

A 10-wk layer feeding trial was conducted to investigate the effects of high quality corn distiller's dried grains with solubles (DDGS) on performance, egg qualities, and yolk fatty acid composition. The economics of using DDGS in the Korean situation was also analyzed. A total of 216 Hy-line Brown layers, 23-wk of age, were employed in this trial consisting of three dietary treatments (0%, 10%, and 20% DDGS), and six replicates per treatment. All experimental diets were prepared as iso-protein (17%) and iso-calorie (2,780 kcal/kg). The use of DDGS up to 20% in layer diets did not affect the feed intake, laying rate, egg weight, and feed conversion ratio (P>0.05). At 5th and 10th wk of the trial, the eggshell color, albumen height, and Haugh unit were not influenced by the DDGS supplementation. At 5th wk of the trial, the eggshell qualities, like eggshell weight, eggshell thickness, and eggshell strength, were not affected by the DDGS feeding; however, these eggshell qualities were decreased at 10th wk due to the 20% DDGS feeding (P

Corn distiller's dried grains with solubles (DDGS) is a completely new feed ingredient in the Korean feed market. There is an ever increasing need for the Korean feed industry to import and make the best of it as a high protein and high energy feed ingredient. A layer feeding trial was conducted for 10 weeks to investigate the effects of addition of light-colored DDGS to layer diets on laying performance, egg qualities and yolk fatty acid composition. Also, the economics of using DDGS in the Korean situation was analyzed. Nine hundred Hy-line Brown layers, 24 weeks of age, were employed in a feeding trial consisting of four dietary treatments (0, 10, 15, and 20% DDGS), and five replicates per treatment. All experimental diets were prepared as iso-protein (17%) and iso-calorie (TMEn 2,780 kcal/kg). The use of DDGS up to 20% in layer diets did not exert any influence on feed intake, laying rate, total egg mass, mean egg weight and feed conversion ratio (p>0.05). The color and breaking strength of eggshell, as well as the albumin height and Haugh unit were not affected by the addition of DDGS up to 20% in the diet. The yolk color was significantly increased by DDGS supplementation (p

This study was evaluated the oxidative stability of the breast and leg meat from chicken fed extract of medicinal herb mix (Lonicera japonica Thunberg : Morus alba L. : Coptis chinensis = 48.5 : 48.5 : 3.0%) and antibiotics (Albac G150). Ross chickens were divided into three treatments: basal diet (control), basal diet with antibiotics (0.05%) and basal diet with extract of medicinal herb mix (0.3%). They were fed the experimental diets for 35 days and slaughtered. After that, the breast and leg meat samples were stored at 4 ℃ for 10 days. Total phenol content of breast meat in Ross chicken fed extract of medicinal herb mix was higher than that of antibiotics treatment and control during storage. DPPH radical scavenging activity was the highest in leg meat of Ross chicken fed extract of medicinal herb mix at 0 day. ABTS + reduction activity was higher in chicken meat fed extract of medicinal herb mix than antibiotics treatment and control. This results showed that the diet with extract of mixed medicinal

Bioavailability of iron in soybean hull was investigated by hemoglobin regeneration efficiency (HRE), body iron status and maze test in rat pups with iron-deficiency anemia (IDA) induced by iron deficiency of dams during gestation or lactation (GID or LID group, respectively) and normal pups (N group). The soybean hull repletion diet (SH) and purified control diet (PC) as the experimental diets contained the same amount of iron (35mg/kg diet) and the pups in each group were divided into two subgroups by diet sources. The normal (N-SH), gestation iron deficiency (GID-SH), lactation iron deficiency (LID-SH) groups fed SH were significantly higher in food intake and growth than each of their respective control groups (N-PC, GID-PC, LID-PC) fed PC. After the feeding, hemoglobin concentrations approached normal value in all groups, but HRE were significantly higher with SH irrespective of iron deficient period. IDA rats in either lactation or gestation, when compared to normal rats, resulted in lower serum iron and transferrin saturation. Iron concentrations in both liver and spleen were significantly lower in LID-PC group than LID-SH and N-PC groups. The maze test showed a learning defect in either LID group, but GID groups were not significantly different in comparison with N groups. These results suggest that IDA in lactation may influence more serious growth and development than those in gestation, soybean hull iron has the higher bioavailability in normal and IDA-induced rats, and thus soybean hull is effective as source of iron supplement.

Above base speed, the flux level must be reduced in inverse proportion to the actual rotor speed. Then the magnetizing inductance is varied by rotor flux reference. In this region, if there is incorrect magnetizing inductance value in the vector controller, it is difficult to properly obtain the magnetizing current and the decoupling terms. The improper magnetizing current decreases the voltage margin, so that makes torque response unstable. Also, improper decoupling terms make voltage reference incorrect. The torques in the stator and rotor flux reference frame have been calculated. If the magnetizing inductance is correct, two torque values are the same. Therefore, if two values are different, the controller has different magnetizing inductance from that of the actual motor. This paper presents the new tuning scheme of the magnetizing inductance by comparing two torque values. The rotor time constant tuning and magnetizing inductance tuning scheme make the vector control system properly operating on the wide speed range. Especially, the improved system performance in the field weakening region by applying this scheme is illustrated. Computer simulation and experimental results demonstrate the efficacy of the proposed scheme.