간행물

한국환경과학회지 KCI 등재 Journal of Environmental Science International

권호리스트/논문검색
이 간행물 논문 검색

권호

제28권 제5호 (2019년 5월) 7

ORIGINAL ARTICLE

1.
2019.05 서비스 종료(열람 제한)
Herein, we analyzed the spatial and temporal variation of DO (dissolved oxygen), BOD (biochemical oxygen demand), and COD (Chemical Oxygen Demand) with the monthly mean observed data for 10 years (2008~2017) in the main stream of the Nakdong River. The water quality of the stations declined in a downstream direction, with the BOD and COD showing their highest values at the ST5 station. From the analysis of the correlation of water quality components at 10 stations, the correlation coefficient between the DO and water temperature was more than –0.90, and that between BOD and Chl-a was 0.48~0.85, and that between COD and TOC was more than 0.65 except for the ST5 and ST10 stations. From the regression analysis using data collected from all stations, the water temperature and DO decreased linearly with a coefficient of determination of 0.90, and the Chl-a and BOD could be described by increasing power functions with a coefficient of determination of 0.83. The TOC and COD followed increasing logarithm functions with a coefficient of determination of 0.58. The TOC efficiency at the 10 stations was estimated and the average efficiencies of BOD and COD were 15.5~36.3% and 57.4~89.6%, respectively.
2.
2019.05 서비스 종료(열람 제한)
The purpose this study was to investigate the influences of 5% turmeric (Curcuma longa L.) supplementation on enzyme activities such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), amylase, lipase and catalase in serum of dyslipidemic rats. Sprague-Dawley (SD) rats (24 male) were divided into four groups, namely the ND group (normal-nondyslipidemic diet), NT group (normal-nondyslipidemic diet+5% turmeric), DD group (control-dyslipidemic diet), and DT groups (dyslipidemic diet+5% turmeric). Serum concentrations of blood urea nitrogen (BUN), creatinine and uric acid were significantly decreased (p<0.05) by turmeric supplementation diet. The activities of AST, ALT, ALP, LDH, amylase and lipase in sera of turmeric diet group were significantly decreased (p<0.05). The catalase activity in serum of turmeric supplementation group was significantly increased than dyslipidemic diet (p<0.05). In vivo experiment with dyslipidemic rats showed that ingestion of turmeric were effective in kidney and hepatic functional enzyme activities. Which suggests that turmeric material could be used for further studies as a potential source for nutraceutical foods.
3.
2019.05 서비스 종료(열람 제한)
The purpose of this study was to investigate the improvement effect of 5% turmeric (Curcuma longa L.) on the blood glucose and lipid metabolism function of streptozotocin (STZ, 45 mg/kg body weight)-induced diabetic rats. Seven-week-old male rats were divided into four groups (n=6), and fed experimental diets containing turmeric meal [basal diet+5% turmeric (BT), basal diet+STZ+5% turmeric (ST)], and control (BD), BS groups (basal diet+STZ). The results of this study, turmeric diet groups (BT, ST) in lipid component as evidenced from the significantly reduction of serum total cholesterol, low density lipoprotein-cholesterol (LDL-cholesterol), atherosclerotic index (AI), cardiac risk factor (CRF), triglyceride (TG), phospholipid (PL), free cholesterol, cholesteryl ester, uric acid, blood glucose, non esterified fatty acid (NEFA), and elevation of high density lipoprotein-cholesterol (HDL-cholesterol). The serum albumin and globulin contents were increased in turmeric supplementation diet than STZ-induced diabetic rats (p<0.05). Concentrations of sodium (Na) and chlorine (Cl) in sera were lower in the turmeric diet than diabetic group. Total calcium (T-Ca), phosphorus (Pi) and potassium (K) concentrations in sera were higher in the BT, ST and BD groups than BS group. In vivo experiments with Sprague-Dawley rats showed that ingestion of turmeric (Curcuma longa L.) were effective in the blood glucose and lipid metabolism functional improvement.
4.
2019.05 서비스 종료(열람 제한)
This study was conducted to investigated the possibility of inactivating wilt germs (Fusarium oxysporum f. sp. radicis lycopersici) using Dielectric Barrier Discharge (DBD) plasma in a hydroponic system. Recirculating hydroponic cultivation system for inactivation was consisted of planting port, LED lamp, water tank, and circulating pump for hydroponic and DBD plasma reactor. Two experiments were conducted: batch and intermittent continuous process. The effect of plasma treatment on Total Residual Oxidants (TRO) concentration change, Fusarium inactivation and growth of lettuce were investigated. In the batch experiment, most of the Fusarium was inactivated at a TRO concentration of 0.15 mg/L or more at four-day intervals. There was no change in lettuce growth after two times of plasma treatment for one week. The intermittent continuous experiment consisted of 30-minute, 60-minute, and 90-minute plasma treatment in 2 day intervals and 30-minute treatment a one-day; most of the Fusarium was inactivated only by treatment for 30-minute every two days. However, if inactivation under 101 CFU/mL is required, it will be necessary to treat for 60 minutes in 2 day intervals. The plasma treatment caused no damage to the lettuce, except the 30 min plasma treatment ay the one-day interval. It was considered that the residual TRO concentration was higher than that of the other treatments.
5.
2019.05 서비스 종료(열람 제한)
To prevent environmental pollution caused by leakage of leachate from waste landfill, vinyl acetate-ethylene (VAE) resin is applied to liner and cover materials to improve their performance. Styrene, styrene butadiene rubber, and VAE are widely used as polymer resins that have excellent water resistance and durability. Further, VAE resin is known to have additional advantages such as adhesion to nonpolar materials and resistance to saponification as a copolymer. In this study, the effect of VAE content on the properties of liner and cover materials was studied. The water and air content ratios, bending and compressive strengths, water absorption ratio, and coefficient of permeability of these materials were measured. The liner and cover materials with 4 wt% VAE showed good properties.
6.
2019.05 서비스 종료(열람 제한)
This study was investigated to improve the phosphorus release and water quality by transformation of sedimentary P fraction for application of CaO2. For the experiment, 0.5% (w/w) of CaO2 was homogenized in the sediment and incubated with the control for 20 days. The analytical results showed that pH increased with CaO2 and redox potential (ORP) was improved in the sediment of the reactor. The growth rate of chlorophyll-a was lower in the CaO2 reactor and Dissolved Oxygen (DO) of overlying water maintained higher than that of the control. Total phosphorus (T-P) concentration in the overlying water increased from the initial concentration to 0.304mg/L in the control at 20 days. The reactor of CaO2 was lowered by 29.3%. Ex-P, Fe-P and Ca-P in sediment P fraction were increased with the CaO2. The formation of bound Fe-P and Ca-P in the sediments seemed to control the release of P by removing the Soluble Reactive Phosphorus (SRP) presented in the pore water. From the result, this indicated that the reduction of P release from the sediments seems to be effective in suppressing the eutrophication of P and improving the oxygen condition in the water quality with the application of CaO2.
7.
2019.05 서비스 종료(열람 제한)
In this study, a solar light collector that collects and transmits solar light required for crop production in a closed plant production system was developed. The solar light collector consisted of a Fresnel lens for collecting solar light, and a tracking actuator for tracking solar light from sunrise to sunset to increase the light collection efficiency. The optical fiber that transmitted solar light was made of Glass Optical Fiber (GOF), and it had an excellent optical transmission rate. After collecting the solar light, the amount of light was measured at 5, 10, 15, 20, 25, and 30 cm distances from the GOF through the darkroom by using a light sensor logger connected to a quantum and pyranometer sensor. Compared with solar light, the light intensity of pyranometer sensor measured at 5 cm was 114% higher than solar light, and 61% at 10 cm. In addition, it was observed that it is possible to transmit the necessary amount of light for growing crops up to about 15 cm (as over 22%) through GOF. Therefore, adding diffusers to the solar light collector should be expected to replace artificial light in plant factories or plug seedlings nurseries for leafy vegetables. More studies on the solar light collection devices and the light transmission devices that have high light collection efficiency should be conducted.