• Economic and Environmental Geology
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• v.28 no.5
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• pp.455-467
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• 1995

In order to investigate the dispersion patterns and speciations of Cu, Pb, Zn and Cd in soils, stream sediments and stream waters, geochemical studies of soil, stream sediment and stream water samples collected in the vicinity of the Shi-Heung Cu-Pb-Zn mine was carried out Cation exchange capacity measurement, size analysis, X-ray diffraction analysis and batch test were performed to select applicable soil for adsorption treatment The average content of Cu, Pb, Zn and Cd in soils collected from tailings and ore dressing plant is 1084 ppm, 2292 ppm, 3512 ppm and 29.2 ppm, respectively, and therefore, tailings and ore dressing plant site may be the major contamination sources in this study area. The mean content of Cu, Pb, Zn and Cd in stream sediments is extremely high up to 794 ppm, 1633 ppm, 2946 ppm and 25.2 ppm, respectively. Tailing particles and heavy metal ions are dispersed along the tributary system. Results from the sequential extraction analysis indicate; (1) most of Cu is bound to organic matters and sulphides, (2) fraction of Pb is mainly bound to Fe and Mn oxides. Most of Zn is largely bound to Fe and Mn oxides and residual fraction. Ion exchangeable fraction of Cd is relatively higher than those of Cu, Pb and Zn. Batch test on soils collected from the kaolinite and/or pyrophyllite mines and from the control areas was carried out to select an applicable soil samples for adsorption treatment The sample, S10, collected from the control area 2 (clay content 33.2%) shows the highest $K_d$ (distribution coefficient). Organic content in soils and several clay minerals shows relatively good correlation with $K_d$. It means that applicable soils for adsorption treatment of heavy metals show high organic and clay content.

• Korean Journal of Agricultural Science
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• v.45 no.1
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• pp.94-104
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• 2018

Nitrite is an essential additive for cured meat product. Plasma is ionized gas and reactive nitrogen species in plasma can be infused into meat batter and subsequently generate nitrites by reaction with water molecules after plasma treatment. However, the increase of nitrite in meat batter is limited with direct treatment of atmospheric pressure cold plasma because of the increase of meat batter temperature. Therefore, this study investigated the influence of indirect treatment of atmospheric pressure cold plasma on the physicochemical properties of meat batter. Meat batter was indirectly treated with plasma at 1.5 kW for 60 min. The pH of meat batter decreased while the temperature increased with plasma treatment time. The total aerobic bacterial count of meat batter was not affected by plasma treatment. The nitrite content of meat batter was increased to 377.68 mg/kg after 60 min of plasma treatment. The residual nitrite content of cooked meat batter also increased with plasma treatment time. The CIE $a^*$-value of cooked meat batter increased. As plasma treatment time increased, lipid oxidation tended to increase and protein oxidation significantly increased. According to these results, the indirect treatment of atmospheric pressure cold plasma can be used as a new curing method for replacing synthetic nitrite salts.

• Elastomers and Composites
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• v.52 no.4
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• pp.295-302
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• 2017

Polyurethane dispersion (PUD) polymers were synthesized by using polyether and polyester polyol. The effect of ionomeric centers, r(NCO / OH) values, chain extender process, and chain extender types on the adhesion properties was investigated. In the case of polyether-based PUD, the ionic center, r value, chain extension process and chain extender types were not adjusted even after adjustment. In the case of polyester-based PUD, when the ionic center content was more than 2.5%, the state of adhesive strength was $2.0kgf/cm^2$ or more. On the other hand, the initial adhesive strength was excellent at about $1kgf/cm^2$ when the ionic center content was over 3.5%. When the r value was 1.3 or more, it was found that the initial bonding strength and the state of bonding strength were excellent at about $1kgf/cm^2$ and $2.1kgf/cm^2$ or higher, respectively. An IR spectrum analysis of the synthesized PUD confirmed that PUD was composed of urethane based on the N-H characteristic peak at $3340cm^{-1}$ and the urethane characteristic peak at $1730cm^{-1}$. Moreover, the characteristic peaks of the isocyanate ($2260cm^{-1}$) used in the preparation of the prepolymer were not observed. As a result, the residual -NCO was not observed, and urethane was completely synthesized.

• Food Science and Preservation
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• v.11 no.2
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• pp.160-169
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• 2004

This study was carried out to investigate the efficacy of electrolyzed water manufactured with or without diaphragm on sterilization and preservation of cut-celery and shelled raw oyster. In cut-celery, total viable cell count and coliform group in the treatment of electrolyzed water were decreased to about 1/200∼1/1,000 level and about 1/100 level comparing non-treated ones. But moisture content, pH, hardness, vitamin C and residual chlorine content were showed a little difference among treatments up to 10 days at 10$^{\circ}C$. L and a color values were gradually increased in all treatments, and color differences($\Delta$E) were remarkable between treatment and untreatment sample. In overall acceptability, cut-celery treated with electrolyzed water showed somewhat higher score than that of other ones treated with tap water and 100 ppm NaClO solution until 5 days of storage. After 48 hours of storage, it was showed that VBN, total viable cell count and coliform count of shelled raw oyster treated with electrolyzed alkali water produced by non-diaphragm system are lower by about 3 mg%, 1∼2 log cycle and 2 log cycle respectively than that of ones treated with sea water. Total viable cell count of shelled raw oyster just after treatment was lower by about 1 log cycle than that of ones treated with sea water, and any significant increment was not found after 24∼48 hours of storage.

• Journal of Life Science
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• v.26 no.11
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• pp.1298-1307
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• 2016

In the study, we investigated the optimum fermentation conditions as well as changes of physicochemical and antioxidant characteristics during the fermentation of jujube wine. The physicochemical characteristics of the jujube hot water extracts used in this study were a pH of 5.05, 0.01% acidity, and $6.5^{\circ}Brix$ concentration. For jujube wine fermentation, the optimal fermentation strain was selected among the isolated strains and the final chosen strain was identified as Saccharomyces cerevisiae, based on the 26S rRNA gene sequencing and similarity searching in GenBank DB. The jujube wine fermented with an initial $15^{\circ}Brix$ concentration of jujube extracts showed a maximum alcohol content of 13% and lower residual sugar concentration. Alcohol content during the jujube wine fermentation was increased after 3 days of fermentation, and no significantly difference after 6 days was found. The residual sugar concentration during the fermentation periods was significantly decreased with increasing alcohol content. The jujube wine properties at 12 days of fermentation were as follows: a pH of 4.34, acidity of 0.29%, alcohol content of 12.8%, and a residual sugar concentration of $8.70^{\circ}Brix$. The malic acid content in the organic acid of fermented jujube wine was significantly decreased during the fermentation proceeding, whereas the succinic acid and lactic acid contents were significantly increased. Antioxidant characteristics of the fermented jujube wine were appeared ABTS radical scavenging activity 45.80%, DPPH radical scavenging activity 61.89%, nitrite scavenging activity 91.95% and total polyphenol compound 3.69 mg/ml. In terms of consumer liking of the jujube wine by sensory evaluation, the color and overall acceptability of jujube wine were evaluated as more than average.

• Toxicological Research
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• v.24 no.3
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• pp.207-212
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• 2008

Pesticide residues play several key roles as environmental and food pollutants and it is crucial to develop a method for the rapid determination of pesticide residues in environments. In this study, a simple, effective, and sensitive method has been developed for the quantitative analysis of methoxyfenozide in water and soil when kept under laboratory conditions. The content of methoxyfenozide in water and soil was analyzed by first purifying the compound through liquid-liquid extraction and partitioning followed by florisil gel filtration. Upon the completion of the purification step the residual levels were monitored through high performance liquid chromatography(HPLC) using a UV absorbance detector. The average recoveries of methoxyfenozide from three replicates spiked at two different concentrations and were ranged from 83.5% to 110.3% and from 98.1% to 102.8% in water and soil, respectively. The limits of detection(LODs) and limits of quantitation(LOQs) were 0.004 vs. 0.012 ppm and 0.008 vs. 0.024 ppm, respectively. The method was successfully applied to evaluate the behavioral fate of a 21% wettable powder(WP) methoxyfenozide throughout the course of 14 days. A first-order model was found to accurately fit the dissipation of methoxyfenozide in water with and a $DT_{50}$ value of 3.03 days was calculated from the fit. This result indicates that methoxyfenozide dissipates rapidly and does not accumulate in water.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.610-612
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• 2008

Piston cores retrieved from the eastern part of the deep-water Ulleung Basin were analyzed to access the potential of hydrocarbon gas generation and natural gas hydrate (NGH) formation. Seismic data acquired in the study area were also analyzed to determine the presence of hydrocarbon gas and/or NGH, and to map their distribution. Core analyses revealed high total organic carbon (TOC) contents which favor hydrocarbon generation. The cores recovered from the southern study area showed the sufficient residual hydrocarbon gas concentrations for the formation of significant NGH. These cores also showed the cracks developed parallel to the bedding that suggest significant gas content in situ. A number of seismic blanking zones were observed on seismic data. They are identified as vertical to sub-vertical chimneys caused by the upward migration of pore fluid or gas, and containing of free gas and/or NGH. Often, they are associated with velocity pull-up structures that are interpreted to be the result of high-velocity NGH. The seismic data also showed several bottom-simulating reflectors (BSRs) that are associated with overlying NGH and underlying free gas. The distribution of blanking zones and BSRs would be impacted by the lateral differences of upward methane fluxes.

• Journal of Yeungnam Medical Science
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• v.38 no.4
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• pp.374-380
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• 2021

Pulmonary alveolar proteinosis (PAP) is an uncommon disease characterized by progressive accumulation of lipoprotein material in the lungs due to impaired surfactant clearance. Whole-lung lavage (WLL) is the current standard treatment and consists of sequential lavage of each lung to mechanically remove the residual material from the alveoli. Although WLL is considered safe, unexpected complications can occur. Moreover, due to the rarity of the disease itself, this procedure is unknown to many physicians, and management of intraoperative complications can be challenging for anesthesiologists. Lung ultrasound (LUS) provides reliable and valuable information for detecting perioperative pulmonary complications and, in particular, quantitation of lung water content. There have been reports on monitoring the different stages of controlled deaeration of the non-ventilated lung during WLL using LUS. However, it has been limited to non-ventilated lungs. Therefore, we report the use of LUS in WLL to proactively detect pulmonary edema in the ventilated lung and implement a safe and effective anesthesia strategy. Given the limited diagnostic tools available to anesthesiologists in the operating room, LUS is a reliable, fast, and noninvasive method for identifying perioperative pulmonary complications in patients with PAP undergoing WLL.

• Korean Journal of Environmental Agriculture
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• v.37 no.3
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• pp.213-220
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• 2018

BACKGROUND: This study was carried out to determine characteristics of residual pesticides in time-dependent manner and calculate half-lives of the residual pesticides in fresh and dried Chinese matrimony vine. In addition, processing factors were calculated based on the residual concentrations in them. METHODS AND RESULTS: The test pesticides, etofenprox and fenitrothion, were sprayed onto the Chinese matrimony vine plants at once or twice (at seven-day interval) and then samples were collected at 0 (after 3 hours), 1, 3, 5 and 7 days after the last spraying. Dried samples were prepared in hot-air drying oven at $60^{\circ}C$ for 48 hours until water content of less than 20%. Residual concentrations of etofenprox in fresh and dried samples decreased by 54.0-60.9% after 7 days of the last pesticide-application. In case of fenitrothion, the concentrations were found to have decreased by 69.2-76.5%. Processing factors of etofenprox were 2.6-3.0 for the one-time spraying and 2.5-3.0 for the two-time spraying and those of fenitrothion were found to be 1.5-22 for the one-time spraying and 1.6-2.0 for the two-time spraying. First half-lives of etofenprox and fenitrothion in fresh and dried samples ranged from 5.0 to 6.3 and from 3.4 to 4.0 days, respectively. The third half-lives were found to be 15.0-18.9 and 10.2-12.1 days, respectively. CONCLUSION: Residual concentrations of the tested pesticides in the studied crop decreased, but those in the dried samples appeared to have increased. In addition, processing factor and half life were constant regardless of spraying times.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.330-337
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• 2005

This study was investigated to elucidate the pesticide mobility in three different soil textures(Heongseong sandy loam; Chuncheon, loam; Taeback, silty clay loam) and four different gravel contents(0, 20, 40, 60%) of Taebaek soil using soil column. Carbofuran, which ranks the highest water solubility among 7 pesticides(carbendazim, carbofuran, chlorpyrifos, cypermethrin, dimethomorph, diniconazole and endosulfan) was defected over 87% in leachate samples within all soil types from early sampling time. Amount of 5 residual pesticides excluding carbendazim and carbofuran were ordered silty clay loam > loam > sandy loam, indicating pesticide residues are related to percentage of clay contents in soils. Comparing the amount of residual pesticides in soil column(upper, middle and lower layer), 6 pesticides apart from carbofuran were found in the range of $50{\sim}92%$ on the upper layer of silty clay loam and loam. Mobility of pesticides either in soil or leachate samples is dependant on water solubility of pesticide and clay content of soil. The results obtained from four different gravel contents of Tacback soil were similar to the results of three different soil textures. Also it was found that more the gravel contents, faster the flow velocity of leachate water. These results possibly provide an idea to select proper pesticides and to reduce soil and water contamination at alpine and sloped-land.