• Journal of Soil and Groundwater Environment
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• v.14 no.3
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• pp.1-13
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• 2009

Alkalinity and total carbon contents were measured by acid neutralizing titration (ANT), back titration (BT), gravitational weighing (GW), non-dispersive infrared-total carbon (NDIR-TC) methods for assessing precision and accuracy of alkalinity and total carbon concentration in $CO_2$-rich water. Artificial $CO_2$-rich water(ACW: pH 6.3, alkalinity 68.8 meq/L, $HCO_3^-$ 2,235 mg/L) was used for comparing the measurements. When alkalinity measured in 0 hr, percent errors of all measurement were 0~12% and coefficient of variation were less than 4%. As the result of post-hoc analysis after repeated measure analysis of variance (RM-AMOVA), the differences between the pair of methods were not significant (within confidence level of 95%), which indicates that the alkalinity measured by any method could be accurate and precise when it measured just in time of sampling. In addition, alkalinity measured by ANT and NDIR-TC were not change after 24 and 48 hours open to atmosphere, which can be explained by conservative nature of alkalinity although $CO_2$ degas from ACW. On the other hand, alkalinity measured by BT and GW increased after 24 and 48 hours open to atmosphere, which was caused by relatively high concentration of measured total carbon and increasing pH. The comparison between geochemical modeling of $CO_2$ degassing and observed data showed that pH of observed ACW was higher than calculated pH. This can be happen when degassed $CO_2$ does not come out from the solution and/or exist in solution as $CO_{2(g)}$ bubble. In that case, $CO_{2(g)}$ bubble doesn't affect the pH and alkalinity. Thus alkalinity measured by ANT and NDIR-TC could not detect the $CO_2$ bubble although measured alkalinity was similar to the calculated alkalinity. Moreover, total carbon measured by ANT and NDIR-TC could be underestimated. Consequently, it is necessary to compare the alkalinity and total carbon data from various kind of methods and interpret very carefully. This study provide technical information of measurement of dissolve $CO_2$ from $CO_2$-rich water which could be natural analogue of geologic sequestration of $CO_2$.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.2
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• pp.101-107
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• 2005

To investigate the effect of pyroligneous acid liquor (PAL) on the maturity of pig manure compost, PAL was treated to the compost piles. The treatments included applications of 100 and 300 times diluted PAL in addition to the control. The compost piles were stirred in three times at the 1st, 10th, and 25th day of composting. Temperature in the compost pile of control treatment increased from 28 to $60^{\circ}C$ within 10 days and remained nearly at the level until 30th day, then it began to decrease. On the other hand, temperature of the PAL-100 and PAL-300 treatments reached 65 to $70^{\circ}C$ within 8 days and became stabilized until 30th day, then the temperature decreased to about $28^{\circ}C$. However, the temperature of control was stabilized approximately at the 40th day. Initially, the pH of control treatment dropped from 8.2 to slightly above pH 8.0 during 4th day, but that of the PAL-100 treatment declined to 7.8. Among treatments, pH value of PAL-100 treatment was the lowest, which was about 7.3 after becoming stabilization. Also the germination index (GI) was increased at all treatments. The C/N ratio range of PAL-100 treatment was better balanced than others and was at 24.3. Moreover the round paper chromatogram of extracted solution of compost of PAL-100 treatment was the sharpest and clearest among treatments. The GI values of control, PAL-100, and PAL-300 in 60 days of composting were about 108, 120, and 118 in germination test using chinese cabbage, respectively. It can be concluded that the addition of diluted PAL solution is effective in composting of pig manure.

• Korean Journal of Community Nutrition
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• v.26 no.4
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• pp.270-279
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• 2021

Objectives: The purpose of this study was to evaluate the effect of the sodium and sugar reduction practices of the Samsam foodservice project of Daegu, in comparison with that of general foodservices in Daegu. Methods: A survey was conducted on 80 Samsam foodservice workers and 80 general foodservice workers from Sep. to Oct. 2020. We compared each worker's taste preferences, stage of behavior change and dietary behavior regarding sodium and sugar, and each foodservice's practices regarding sodium and sugar reduction. Results: There was no significant difference between the salty taste and sweet taste preferences between the workers at the Samsam foodservices and those at the general foodservices. The percentage of foodservice workers in action or maintenance stage of behavior change for eating less salty was higher in the Samsam foodservices than in the general foodservices (P < 0.05). In addition, regarding the degree of saltiness and sweetness of meals, the workers at the general foodservices perceived their meals to be saltier (P < 0.001) and sweeter (P < 0.01) than the workers at Samsam foodservices. The workers at Samsam foodservices had fewer salty dietary behaviors compared to the workers at general foodservices (P < 0.01). The sodium reduction practice was significantly higher in the Samsam foodservices than the general foodservices (P < 0.001), especially in "efforts to make the food as bland as possible overall" (P < 0.001), and "serving less soup and stew" (P < 0.001). The sugar reduction practice too was significantly higher in the Samsam foodservices than the general foodservices (P < 0.001). Conclusions: The Samsam foodservices were shown to be better in the practice of sodium and sugar reduction compared to general foodservices. Therefore, it is necessary to provide continuous and practical support and incentives at the national level to expand the sodium and sugar reduction practices in foodservices.

• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.799-808
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• 2021

This study was performed to investigate the extent of microbial contamination, the presence of enterotoxin genes, and the antibiotic susceptibility of Bacillus cereus in 58 red pepper plants and 43 environmental samples (soil, irrigation water, and gloves) associated with the plant cultivation. The detected counts of total aerobic bacteria, coliform bacteria, Escherichia coli, Bacillus cereus, and Staphylococcus aureus were lower in these samples, as compared to the regulations of standards for foods; moreover, pathogens, such as E. coli, E. coli O157:H7, Listeria monocytogenes, and Salmonella spp., were not detected. Genes encoding hemolysin BL enterotoxins (hblA, hblC, and hblD) as well as non-hemolytic enterotoxins (nheA, nheB, and nheC) were detected in 23 B. cereus specimens that were isolated from the test samples and had β-hemolytic activity. Interestingly, B. cereus is resistant to β-lactam and susceptible to non-β-lactam antibiotics. However, in this case, the isolated B. cereus specimens exhibited a shift from resistant to intermediate in response to cefotaxime and from susceptible to intermediate in case of rifampin, trimethoprim-sulfamethoxazole, vancomycin, clindamycin, and erythromycin. Therefore, the levels of B. cereus should be monitored to detect changes in antibiotic susceptibility and guarantee their safety.

• Journal of Life Science
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• v.31 no.10
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• pp.937-943
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• 2021

In this study, antibacterial activity against pathogenic strains and antioxidant activity were measured using the red pine leaf distilled concentrate. The results of the antibacterial activity measured using an emulsion of the red pine leaf distilled concentrate by the paper disc method showed the antibacterial activities against three Gram negative pathogenic strains, E. coli, S. typhi and Vibrio parahaemolyticus and exhibited growth inhibitions of 12 mm, 10 mm and 9 mm at a 5.0% (v/v) concentration, respectively. In addition, all three strains also showed growth inhibitions even at 0.5% (v/v) concentration. However, no antibacterial activity was exhibited against gram positive bacteria. The results of the antibacterial activity using the red pine leaf distilled concentrate measured by the turbidity method, the same antibacterial activities against three gram negative pathogenic strains, E. coli, S. typhi and V. parahaemolyticus as results of the paper disc method. V. parahaemolyticus showed more than 50% growth inhibition compared to the negative control at a concentration of 5% (v/v), E. coli exhibited 33.5% growth inhibition at 4 hr incubation, and S. typhi showed 65.1% and 44.6% growth inhibitions at 4 and 5 hr incubations, respectively. Antioxidant activities of an emulsion of the red pine leaf distilled concentrate were measured by DPPH and ABTS methods. DPPH method showed the highest activity of 55.81% at a 1.0% (v/v) concentration. ABTS method exhibited the highest activity of 18.44% at a 1.0% (v/v) concentration. Through this study, it is expected that the developments of the food and the cosmetics with enhanced functionality by utilizing the antioxidant and antibacterial activities of the red pine leaf distilled concentrate.

• Korean Journal of Mineralogy and Petrology
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• v.34 no.3
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• pp.157-167
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• 2021

Lead (Pb) is one of the key trace elements, exhibiting a peculiar partitioning behavior into silicate melts in contact with minerals. Partitioning behaviors of Pb between silicate mineral and melt have been known to depend on melt composition and thus, the atomic structures of corresponding silicate liquids. Despite the importance, detailed structural studies of Pb-bearing silicate melts are still lacking due to experimental difficulties. Here, we explored the effect of lead content on the atomic structures, particularly the evolution of silicate networks in Pb-bearing sodium metasilicate ([(PbO)_x(Na₂O)_1-x]·SiO₂) glasses as a model system for trace metal bearing natural silicate melts, using ²⁹Si solid-state nuclear magnetic resonance (NMR) spectroscopy. As the PbO content increases, the ²⁹Si peak widths increase, and the maximum peak positions shift from -76.2, -77.8, -80.3, -81.5, -84.6, to -87.7 ppm with increasing PbO contents of 0, 0.25, 0.5, 0.67, 0.86, and 1, respectively. The ²⁹Si MAS NMR spectra for the glasses were simulated with Gaussian functions for Qⁿ species (SiO₄ tetrahedra with n BOs) for providing quantitative resolution. The simulation results reveal the evolution of each Qⁿ species with varying PbO content. Na-endmember Na₂SiO₃ glass consists of predominant Q² species together with equal proportions of Q¹ and Q³. As Pb replaces Na, the fraction of Q² species tends to decrease, while those for Q¹ and Q³ species increase indicating an increase in disproportionation among Qⁿ species. Simulation results on the ²⁹Si NMR spectrum showed increases in structural disorder and chemical disorder as evidenced by an increase in disproportionation factor with an increase in average cation field strengths of the network modifying cations. Changes in the topological and configurational disorder of the model silicate melt by Pb imply an intrinsic origin of macroscopic properties such as element partitioning behavior.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.5
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• pp.112-124
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• 2021

This study was conducted to examine and analyze local governments, park status, project characteristics, and the implementation in detail for private park special projects across the country as a means of responding to the sunsetting of urban parks. As a result of the analysis, first, the private park special project, was found to be mainly implemented in cities with a population of more than 100,000, so there was a limit to the application on military installations or in local small cities. Therefore, rather than applying the special system collectively, it was judged that institutional flexibility, considering the characteristics and size of local government, was needed. Second, the current special projects by the park creation donation collection method shows monotonous development centered on apartment houses, so it is necessary to diversify the development by introducing a park preservation method that purchases and donates park sites. Third, it was found that the area standard needs to be eased to less than 50,000m² to include parks with high utilization and good accessibility in urban areas of large cities, as the type and area of parks are limited. Fourth, most special projects are mountain parks, which are feared to damage the natural terrain and skyline, so separate ordinances should be established and applied, and development approaches should be made to allow nature and parks to coexist with the setting of detailed building guidelines for each type of facility. The guidelines should include, first, after the nationwide private park special projects are completed, standards for appropriate returns for similar projects should be established, institutional standards such as the recovery of excess profits should be established, and environmental reviews should be conducted. Second, it was found that local governments should institutionalize the composition of private consultations to promote the efficient management of projects through a cooperative system, and third, a roadmap for maintenance after the donation of special parks should be established.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.674-678
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• 2010

A new sweetpotato variety, 'Daeyumi', was developed by Bioenergy Crop Research Center, National Institute of Crop Science (NICS), RDA in 2008. This variety was obtained from the cross between 'Jinhongmi' and 'Xusju 18' in 2000. The seedling and line selections were performed from 2001 to 2003, preliminary and advanced yield trials were carried out from 2004 to 2005, and the regional yield trials were conducted at six locations from 2006 to 2008. 'Daeyumi' has cordate leaf, green vine and petiole, elliptic storage root, red skin and yellow flesh color of storage root. This variety is also resistant to Fusarium wilt and nematode. The starch value was 25.9%, ethanol yield was 418 L/Ton, which was 7% higher than that of 'Yulmi' variety, and the total sugar content was 2.47 g/100g, dry weight. 'Daeyumi's initial temperature of starch gelatinization was lower, 76.2$^{\circ}C$, and the retrogradation process was earlier than 'Yulmi'. The average yield of storage root was 27.8 ton/ha in the regional yield trials, which was 36% higher than that of 'Yulmi' variety. Number of storage roots over 50 gram per plant was 3.0, and the average weight of one storage root was 152 gram. This variety can be used for the production of bioethanol and starch processing.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.679-683
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• 2010

'Yeonjami' is a new sweetpotato variety developed for table use by Bioenergy Crop Research Center, National Institute of Crop Science (NICS), RDA in 2008. This variety was selected from the cross between 'Ayamurasakki' and 'Poly Cross' in 2000, and seedling and line selections were practiced from 2001 to 2003. Preliminary and advanced yield trials were carried out from 2004 to 2005. The regional yield trials were conducted at six locations from 2006 to 2008. 'Yeonjami' has cordate leaf, green vine and petiole, long elliptic storage root, purple skin and light purple flesh color of storage root. The average yield of storage root was 25.9 ton/ha in the regional yield trials, which was 15% higher than that of 'Sinjami' variety. Number of storage roots over 50 gram per plant was 2.9, and the average weight of one storage root was 153 gram. This variety was partly-resistant to Fusarium wilt and nematode. In addition, steamed 'Yeonjami' has higher polyphenol contents as 139.6 mg/100 g and higher biological activities as, which may improve the bioactivity in human.

• Korean Journal of Environmental Agriculture
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• v.37 no.4
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• pp.283-290
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• 2018

BACKGROUND: Pesticide residue analysis is an essential activity in order to establish the food safety of agricultural products. Analytical approaches to the food safety are required to meet internationally the guideline of Codex (Codex Alimentarius Commission, CAC/GL 40). In this study, we developed a liquid chromatograph-tandem mass spectrometer (LC-MS/MS) method to determine the herbicide clopyralid in food matrixes. METHODS AND RESULTS: Clopyralid was extracted with aqueous acetonitrile containing formic acid and the extracts were mixed in a citrate buffer consisted of magnesium sulfate anhydrous, NaCl, sodium citrate dihydrate and disodium hydrogencitrate sesquihydrate followed by centrifugation. The supernatants were filtered through a nylon membrane filter and used for the analysis of clopyralid. The method was validated by accuracy and precision experiments on the samples fortified at 3 different levels of clopyralid. LC-MS/MS in positive mode was employed to quantitatively determine clopyralid in the food samples. Matrix-matched calibration curves were inearranged from 0.001 to 0.25 mg/kg with r2 > 0.994. The limits of detection and quantification were determined to be 0.001 and 0.01 mg/kg, respectively. There covery values of clopyralid for tified at 0.01 mg/kg in the control samples ranged from approximately 82 to 106% with relative standard deviations below 2 0%. CONCLUSION: The method developed in this study meets successfully the Codex guideline for pesticide residue analysis in food samples. This, the method could be applicable to determine pesticides in foods produced domestically and internationally.