• Journal of Environmental Science International
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• v.21 no.9
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• pp.1115-1129
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• 2012

The objective of this study was to analyze long-term annual and seasonal trends of water chemistry on landuse patterns and seasonal precipitation using 72 sampling sites within Namhan River watershed during 2001-2010. Water quality, based on multi-parameters of water temperature(WT), dissolved oxygen(DO), biochemical oxygen demand(BOD), chemical oxygen demand(COD), suspended solids(SS), total nitrogen(TN), total phosphorus(TP), and electric conductivity(EC) varied largely depending on monsoon rain and landuse patterns such as forest, cropland, and residence. Concentrations of BOD and COD as an indicator for organic matter pollution, increased during summer monsoon season at the cropland and residential streams. Values of TN and TP were higher in residential streams than in the forest and cropland streams. In the meantime, DO values had weak relations to the landuse patterns of forest and cropland cover. Water quality was worst in cropland and residential streams, and also most degradated in 4th order streams. Overall, our results suggest that efficient water quality management is required in the cropland and residential landuse streams.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2004.12a
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• pp.127-131
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• 2004

The toxicity of 54 selected process effluents of 16 industry classifications in Korea was evaluated by bioassay test using fish Oryzias latipes, invertebrate Daphnia magna, algae Selenastrum capricornutum and bacteria Vibrio fischeri. Our results demonstrate that the toxicity assessment, such as bioassay test, is effective and of practical use for industrial wastewater management in 54 selected effluents with the limitation of the physico-chemical permit. Among 54 effluents, 4 sample failed physico-chemical permit limitation and 50 passed it. The physcio-chemical measurement items and permit concentrations on the present Water Quality Conservation Act are low related a ecotoxicity.

• Horticulture, Environment, and Biotechnology : HEB
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• v.59 no.6
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• pp.847-856
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• 2018

This research aimed to evaluate the effectiveness of hot water ($43-53^{\circ}C{\cdot}5min^{-1}$; $47^{\circ}C{\cdot}2-6min^{-1}$), 1-methylcyclopropene (1-MCP) at $50-300nL\;L^{-1}$ and a combination of hot water ($47/49^{\circ}C{\cdot}5min^{-1}$) and phosphite $40%\;P_2O_5+20%\;K_2O$;$40%\;P_2O_5+10%\;Zn$) in anthracnose control and the effect on fruit quality [fresh weight loss (FWL-%); pH, total soluble solids ($TSS-^{\circ}Brix$), and titratable acidity (TA = % citric acid (CA)] of passion fruit ( Passiflora edulis f. flavicarpa ) at the postharvest stage. When the fruits were in the stage of 0% dehydration and fully yellow peels, they were disinfested and inoculated with Colletotrichum gloeosporioides. They were then subjected to the above mentioned treatments; this was followed by incubation for 120 h. The diameter of the disease lesions was monitored daily. After the incubation, a physico-chemical analysis was performed. Hot-water treatment resulted in disease reduction at 47 and $49^{\circ}C$ for 4 and 5 min. The combination of hot-water treatment at $47^{\circ}C$ (4 or 5 min) and application of the phosphite of K or Zn significantly reduced disease severity in fruits. The 1-MCP treatment reduced anthracnose severity in passion fruit mainly at $200nL\;L^{-1}{\cdot} 24h^{-1} $. None of the treatments significantly changed the physico-chemical characteristics of the fruit [FWL (2.6-4.1%); pH (3.2-3.5), TSS ($8.9-10.9^{\circ}Brix$), and TA (1.8-2.5% CA)].

• Food Science of Animal Resources
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• v.36 no.5
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• pp.617-625
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• 2016

Pastırma, a dry-cured meat product, is produced from the whole muscle and/or muscles obtained from certain parts of beef and water buffalo carcasses. The purpose of this study was to determine the effects of different levels of sodium nitrite on changes in the physicochemical and microbial quality during the production of pastırma. The changes in residual nitrite, salt, pH, moisture, thiobarbutiric acid reactive substances (TBARS), colour (L*, a*, b*), total aerobic mesophilic bacteria (TAMB), lactic acid bacteria (LAB), Micrococcus/Staphylococcus (M/S), mould-yeast (M-Y), and Enterobacteriaceae counts of pastırma with 0, 50, 100 and 150 ppm sodium nitrite were determined during the production. The nitrite levels and the production stages had significant effects (p<0.01) on residual nitrite, TBARS, pH, salt, and colour values. The TBARS values of the pastırma with nitrite were significantly lower (p<0.05) than the control. The final TAMB, LAB, M/S, and M-Y counts of pastırma with 150 ppm nitrite were significantly (p<0.05) lower than the control. Also, the a* (relative redness) values of control pastırma were significantly lower (p<0.05) than the pastırma with nitrite. The production stages had a significant effect (p<0.01) on the moisture.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.2
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• pp.252-259
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• 2015

The present study was conducted to investigate the efficacy of sweet potato powder (SPP) and water as a fat replacer in low-fat pork patties. Low-fat pork patties were developed by replacing the added fat with combinations of SPP and chilled water. Three different levels of SPP/chilled water viz. 0.5/9.5% (T-1), 1.0/9.0% (T-2), and 1.5/8.5% (T-3) were compared with a control containing 10% animal fat. The quality of low-fat pork patties was evaluated for physico-chemical (pH, emulsion stability, cooking yield, $a_w$), proximate, instrumental colour and textural profile, and sensory attributes. The cooking yield and emulsion stability improved (p<0.05) in all treatments over the control and were highest in T-2. Instrumental texture profile attributes and hardness decreased, whereas cohesiveness increased compared with control, irrespective of SPP level. Dimensional parameters (% gain in height and % decrease in diameter) were better maintained during cooking in the low-fat product than control. The sensory quality attributes juiciness, texture and overall acceptability of T-2 and T-3 were (p<0.05) higher than control. Results concluded that low-fat pork patties with acceptable sensory attributes, improved cooking yield and textural attributes can be successfully developed with the incorporation of a combination of 1.0% SPP and 9.0% chilled water.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.4
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• pp.548-553
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• 2004

Patties were prepared using Barbari male goats meat (age about 4 yrs) and packed in HDPE under vacuum (VP) and aerobically (AP). Packed patties were stored at 4$\pm$1$^{\circ}C$ and evaluated for physico-chemical, microbiological and sensory changes on days 0, 5, 10, 15, 20 and 25. Overall mean water activity ($a_{w}$), moisture (%), fat (%), pH, TBA number and W-B shear force values (kg/$cm^{2}$) of patties were 0.983, 61.93, 18.39, 6.38, 0.150 and 0.86, respectively. Except pH that was significantly higher and TBA number significantly lower in VP patties, treatment had no significant (p>0.05) effect on other physico-chemical traits. However, storage period significantly (p<0.05) affected physico-chemical traits. Moisture (63.79%) and $a_{w}$ (0.985) were significantly (p<0.05) higher on day 25. Patties became firmer on day 20 onwards as indicated by higher W-B shear force. Though packaging method had no significant effect, storage period influenced microbial counts. The standard plate counts (SPC), which were initially log 5.98 CFU/g decreased significantly (p<0.05) on day 10 followed by steady increase and reaching log 4.89 on day 25. Almost similar trend was observed for psychrotrophic bacteria counts. Lactic acid bacteria counts declined as the storage period progressed. Coliforms, and yeast and mould counts were either not detected by the method used or were very low in numbers. All samples of AP patties revealed swollen, greasy and sticky surface with spongy texture on day 20 whereas only some of the VP patties shown such changes on day 20. Results indicated that vacuum packaging had definite advantage in preserving the sensory quality of patties than aerobic packaging but it did not help in extending the shelf-life beyond 15 days.

• Proceedings of the Korea Concrete Institute Conference
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• 1994.10a
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• pp.151-156
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• 1994

This study is to investigate the quality of superplasticizers in domestic market. Therefore, the physico-chemical characteristics, the fluidity characteristics of fresh cement paste and mortar were tested. Also fresh and hardened properties of mortars and concretes using these superplasticizers were tested. From these results, differences of quality among superplasticizers are checked clearly in low water/cement ratio. And it is concluded that several superplasticizers have better dispersion ability than others in every tests. It has known that all samples are naphtalene sulfornate formaldehede types by the UV(ultra-violet) test.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.4
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• pp.1021-1030
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• 2015

For the water quality improvement in the ocean outfall area of sewage treatment plant, this study tried to control the water quality of outfall area using the biofilter method through seaweeds, a way of ecological engineering treatment that is applicable in the marine ecosystem. Therefore, this research made an attempt the main factors necessary for creating seaweed bed to improve water quality in the outfall area of sewage treatment plant, and the results are as follows. In the case of making the seaweed bed in the ocean outfall area of sewage treatment plant, Habitat Suitability Index of Ecklonia cava per all survey points, considered physical and physico-chemical factors in 5~10 meters below sea level, was 50~93% (average 80%), so this seaweed, Ecklonia cava, was suitable for making the seaweed bed.

• Journal of Korean Society on Water Environment
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• v.26 no.1
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• pp.10-18
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• 2010

Water quality and the distribution of ammonia oxidizing bacteria were characterized in constructed wetland of Shihwa lake. Both physico-chemical parameters and fecal indicator microorganisms including total coliforms, E.coli, Enterococcus spp. were measured. In addition, denaturant gradient gel electrophoresis (DGGE) was carried out after PCR amplification of amoA gene from input, output, and wetland sites of the Banwol, Donghwa, and Samhwa stream in Shihwa lake area. Physico-chemical parameters were in proper range for typical nitrifying bacteria to grow and perform their biological activities. Average concentrations of fecal indicator microorganisms of wetland samples were lower than those of input sites. These results suggested that microbial water quality improved by the process of constructed wetland. According to phylogenetic information obtained from DGGE from study sites, distribution of nitrifying bacteria from each of input, output, and wetland were generally distinctive one another. In addition, distribution of nitrifying bacteria between Banwol and Donghwa streams showed higher similarity (52.6%) than this of Samhwa stream (15.2%). These results indicated that characteristics of ammonia oxidizing bacteria in Samhwa were unique in comparison with those of Banwol and Donghwa stream.

• Journal of Life Science
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• v.19 no.7
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• pp.943-948
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• 2009

Physical and chemical analyses of water discharged from 4 crowded farms (Sungsan, Pyosun, Wimi and Daejung) in Jeju island were performed from July, 2006 to Dec, 2006, and the result of the analyses showed that hydrogen ion concentrations (pH) for water discharged from Sungsan farm was 7.74, Pyosun was 7.68, Wimi was 7.68 and Daejung was 7.7. Salinity levels for Sungsan, Pyosun and Wimi had an average of 31$\sim$33 $^\circ$/$_\circ$$_\circ$ indicating characteristics of far distance areas, whereas that of Daejung was 28.81 %, which was far lower compared to regular sea water salinity. As the result of measuring dissolved oxygen (DO) for each area, each area showed first graded DO for each discharged water based on water quality level for each sea district. The result of measuring the temperature for discharged water showed that water temperatures for summer were 23$\sim$25$^\circ$C, and those for winter were 16$\sim$ 18$^\circ$C. Nitrogen concentrations for discharged water exceeded each sea area's water quality level in all farms. In the case of phosphate, its average value was 0.48 mg/l for Sungsan, 0.55 mg/I for Pyosun, 0.66 mg/I for Wimi, and 0.44 mg/l for Daejung, and chemical oxygen demand (COD) was shown to be 1.5 mg/l 1.8 mg/I, 1.6 mg/I and 2.3 mg/I for Sungsan, Pyosun, Wimi and Daejung respectively. For suspended solids (SS), the average concentration was 19.3 mg/I, 21.2 mg/I, 21.3 mg/I and 18.5 mg/I for Sungsan, Pyosun, Wimi and Daejung respectively. The results of physical and chemical analyses for discharged water in farms based on time showed that almost all items were shown to increase in the forenoon and decrease, overall, in the afternoon.