• Journal of the Korean Applied Science and Technology
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• v.33 no.3
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• pp.575-586
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• 2016

An experiment was carried out to determine the effect of cooling water treatment with ionized calcium on calcium content, extending the shelf-life and quality of fresh chicken meat in poultry slaughtering process. The subjects were divided into four groups: control (0% without ionized calcium) and treatment groups (0.5, 0.7, 0.9% ionized calcium). The results indicated that the cooling water treatment with ionized calcium exhibited the bacterial counts of $10^5CFU/cm^2$ in surface of chicken meat, and maintained the quality of fresh chicken meat with extending the shelf-life above seven days when compared with that of control group. The results found that the cooling water treatment with ionized calcium could produce the calcium enrichment of chicken meat as nine times higher in calcium content of chicken meat when compared with that of control group. pH, water holding capacity, TBARS (MDA mg/kg) in chicken meat via the cooling water treatment with ionized calcium showed 6.4, above 50, below 0.10, respectively, with preventing the oxidation of unsaturated fatty acids. Lightness ($L^*$) as a chicken meat color, shear force indicated above 60, below $1.70kg/0.5inch^2$, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.506-515
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• 2003

Six barley varieties that showed different degree of drought tolerance were grown with and without drought stress treatment (control), and investigated for the temporal changes in growth and several physiological traits after drought treatment. Soil water potential was -0.05 ㎫ at the initial stage of drought treatment and dropped to -0.29 ㎫ at 19 days after withholding irrigation. Soil water potential (SWP) maintained at -0.05 ㎫ in the control. The dry weight (DW) under the drought treatment were reduced compared to the control as follows: Dicktoo-S (short awn), 69% ; Dicktoo-L (long awn), 70%; Dicktoo-T (tetra), 86%; Dongbori-1, 69%; Suwonssalbori-365, 55% and Tapgolbori, ,37%. Dicktoo lines and Dongbori-1 were more tolerant than Suwonssalbori-365 and Tapgolbori. Leaf relative water contents (RWC) and leaf water potential (LWP) decreased obviously under the drought condition, the decrease being greater especially in the less drought-tolerant barley genotypes. Dongbori-1 and Dicktoo-L in drought treatment showed net photosynthesis of 38% and 17% compared to the control, respectively, and the other four genotypes much lower photosynthesis of 1.1% to 7.0%. Stomatal conductance, mesophyll conductance, and the photochemical efficiency (Fv/Fm) of PS II were reduced by drought treatment, the reduction being greater in drought-sensitive genotypes. The drought-tolerant genotypes had greater osmotic adjustment (OA) capacity under water stress. Thus, the decrease of RWC and LWP was lower and the turgor pressure conservation capacity was higher under water stress in drought-tolerant genotypes. Drought-tolerant genotypes showed less decrease of photosynthesis because stomatal conductance, mesophyll conductance and the ratio (Fv/Fm) of the variable to maximal fluorescence of drought-resistant genotype was decreased less in the drought stress condition. In conclusion, the drought-tolerant genotypes had better water conservation capacity through efficient OA, and this led to the lower decrease of photosynthesis and growth in water stress condition.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.2
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• pp.281-287
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• 2006

Maintaining adequate chlorine residual is crucial in water treatment facilities, Treatment technique, newly promulgated regulation, requires sufficient disinfection in order to control more resistant microorganisms such as Viruses and Giardia lamblia. Each water treatment plant should report various water qualities including chlorine residual and disinfection by-products, thus plenty of data has been generated. Even though statistical analysis using these data are forced to investigate the status and effect of water qualities in water facilities very few researches have been performed in korea. This study performed statistical analysis of chlorine residual during three years in Korean drinking water. The average chlorine residual concentrations were 0.701mg/L, 0.738mg/L, 0.763mg/L in 2002, 2003, 2004, respectively. Monthly variations of chlorine residual was not significant. ANOVA result showed that yearly variance of chlorine residual is different in only less than $5000m^3/day$ of water treatment capacity. The statistical analysis can help government to establish new regulation with scientific basis.

• Journal of Korea Water Resources Association
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• v.52 no.11
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• pp.947-950
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• 2019

The main feature of this paper is to provide a driving control strategy to improve the primary clarifier treatment efficiency in the initial rainfall inflow. With the recent development of IoT technology and sensing technology, the basis for operation control of wastewater treatment facilities has been improved. As a result of improving the efficiency of treatment of primary clarifier using on-line measurement results, it is possible to minimize the outflow of untreated sewage and contribute to the improvement of operation efficiency of wastewater treatment plants.

• Toxicological Research
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• v.13 no.4
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• pp.323-325
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• 1997

Ag-Os, water treatment agent, was administered orally to ICR mice and Sprague-Dawley rats to investigate the acute oral toxicity. $LD_{50}$ values were above 5 g/kg, 2,000 fold higher than the expected concentration in water, in both species with oral administration. There were also no differences in body weight changes, clinical signs and atopsy findings between all treated groups and control group. Therefore, it was concluded that Ag-Os is a very safe compound.

• Journal of Wetlands Research
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• v.11 no.2
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• pp.1-7
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• 2009

In order to select the water flooding-tolerant trees among Korean oaks, we cultivated the sapling of 6 deciduous oak species, Quercus acutissima, Q. mongolica, Q. variabilis, Q. dentata, Q. aliena and Q. serrata, under the water flooding treatment and the control, and analysed the growth difference among them. For comparing the growth between treatment and control, we measured 13 morphological and ecological traits, such as leaf Leaf number, leaf length, leaf width, leaf area, shoot length, stem length, stem diameter, root length, plant length, leaf weight, stem weight, root weight, plant weight. Q. serrata have no growth difference between water flooding treatment and control, but the rest 5 species showed the growth reduction in water flooding treatment. Tolerance of oak species to water flooding was risen in order of Quercus acutissima, Q. mongolica, Q. variabilis, Q. dentata, Q. aliena and Q. serrata. Thus, among Korean deciduous oaks, it is desirable to plant Q. serrata for flood plain restoration of river.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.2
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• pp.42-51
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• 2010

Herbs and shrubs are employed for environmental restoration purposes. Among common herbs and shrubs, few species with low germination rates were selected and studied for enhanced germination rates and decreased germination times via soaking treatment. Rhus chinensis, incubator grown samples treated with the bacterial solution for 72hrs followed by immediate seeding showed the highest germination rate of 26.7% and germination period of 5.7 days, 3 days decrease from the control. Treatment of distilled water (t=3.79, p<0.01), nutrient broth (t=4.44, p<0.00) and bacterial solution (t=4.42, p<0.00) showed highly significant difference. In the case of soil tests, treating in the nutrient broth for 72 hrs followed by immediate seeding yielded the the highest germination rate of 23.3% with 7.3 days to initial germination, a decrease of 14.7 days with respect to the control. All the samples followed by immediate seeding showed significant difference (t=2.13, p<0.05). Incubator grown samples of Lespedeza cyrtobotrya showed different results. The incubator samples suspended for 48 hrs in distilled water followed by immediate seeding and 1 day drying displayed the highest germination rate of 96.7%, surpassing that of the control by 33.4%. The incubator samples treated with the distilled water and nutrient broth showed enhanced germination. But only the samples treated with distilled water and nutrient broth for 48hrs showed the increased germination in soil tests. All the sample treated for 24 hrs followed by immediate seeding or dried for 1 day showed initial germination as early as 1 day in incubator. The initial germinations were shortened in the samples treated with distilled water and nutrient broth for 48hrs in soil tests. Lespedeza cuneata incubator sample treated with nutrient broth for 24 hrs and dried for 1 day exhibited the highest germination rate of 83.3%, a 31.1% improvement over the control. The incubator samples treated with distilled water for 48 hrs (t=4.20, p<0.01) showed effective increase of germination. The treatment of distilled water (t=2.96, p<0.05) and bacterial solution (t=2.24, p<0.05) showed significant difference. The germination rates in soil were less than those of incubator and the control. The incubator samples treated with distilled water and bacterial solution displayed 1 day germination period, shortened by 1.3 days compared to the control. For soil grown samples, the samples treated with distilled water showed delayed initial germination and those treated with nutrient broth for 48hrs and bacterial solution for 72hrs shortened initial germination.

• Environmental Engineering Research
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• v.21 no.4
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• pp.319-332
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• 2016

Micropollutants are often discharged to surface waters through untreated wastewater from sewage treatment plants and wastewater treatment plants. The presence of micropollutants in surface waters is a serious concern because surface water is usually provided to water treatment plants (WTP) to produce drinking water. Many micropollutants can withstand conventional WTP systems and stay in tap water. In particular, pharmaceuticals and endocrine disruptors are examples of micropollutants that are detected at the drinking water, ppb, or even ppb level. A variety of techniques and processes, especially advanced oxidation processes, have been applied to remove micropollutants from water to control drinking water contamination. This paper reviews recent researches on the occurrence and removal of micropollutants in the aquatic environments and during water treatment processes.

• Fisheries and Aquatic Sciences
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• v.7 no.1
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• pp.16-22
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• 2004

Plasma steroid hormone levels in the viviparous rockfish (Sebastes schlegeli) were examined in relation to gonadal histology under controlled photoperiods and water temperatures. To investigate those effects in S. schlegeli the photoperiod was maintained at 15L:9D in June and then it was gradually decreased to 9L: 15D in October. It was then gradually increased to 12L:12D in January, followed by 14L:I0D in February. The water temperature was $19-20^{\circ}C$ in July. From August to October, it was from $18^{\circ}C\;to\;12^{\circ}C$. Then, it was dropped to a low of $19-11^{\circ}C$ in November to December and then gradually increased to $14-15^{\circ}C$ in February. In females, both plasma $estradiol-l7\beta\;$ (E2) and testosterone (T) levels from August to February showed a similar pattern in both the treatment and the control groups. In the treatment group, the peaks of plasma E2 and T were observed in November, and the peaks were closely correlated to histological observations. Oocytes contained many yolk globules (final vitellogenic oocytes), and oocytes at the migratory nucleus stage increased in size. Plasma levels of progesterone did not change much throughout the experimental period. However, in the control group, the peaks of E2, T, and progesterone were observed in February. These results indicate that the controlled photoperiod and water temperature accelerated sexual maturity, corresponding to the advancement of plasma E2 and T peaks by approximately 3 months. In males, plasma T levels showed a similar pattern from August to October in the treatment and control groups, though levels in the treatment group were higher than those in the control group. From histological observations, the treatment group copulated one month earlier.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.5
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• pp.616-622
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• 2011

This study evaluated the fermentation characteristics and protein degradation dynamics of wet green tea grounds (WGTG) silage. The WGTG was ensiled with distilled water (control), or lactic acid bacteria (LAB), enzyme (E), formic acid (FA) and formaldehyde (FD) prior to ensiling. Three bag silos for each treatment were randomly opened at 0, 3, 7, 14, 28 and 60 days after anaerobic storage. For all the treatments, except for FA, there was a rapid decline in pH during the first 7 days of ensiling. LAB treatment had higher lactic acid content, lower ammonia-N ($NH_3$-N) and free-amino nitrogen (FAA-N) contents than other treatments (p<0.05). E treatment had higher lactic acid, water-soluble carbohydrates (WSC) and non-protein nitrogen (NPN) content than the control (p<0.05). FA treatment had higher $NH_3$-N and FAA-N content than the control (p<0.05). FD treatment had lower NPN and FAA-N content than the control, but it did not significantly inhibit the protein degradation when compared to LAB treatment (p>0.05). Results indicate that LAB treatment had the best effect on the fermentation characteristics and protein degradation of WGTG silage.