• The Korean Journal of Malacology
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• v.30 no.4
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• pp.421-428
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• 2014

Total 20 surface sediments were collected in Anjung bay to investigate the physicochemical environment and heavy metal contents. The physicochemical investigation ranged from 6.41% to 11.68% (average $9.52{\pm}1.28%$) for ignition loss (IL), from 17.99 mg/g to 43.84 mg/g (average $27.53{\pm}6.39mg/g$) for chemical oxygen demand (COD), and from 0.05 mg/g to 0.61 mg/g (average $0.17{\pm}0.14mg/g$) for acid volatile sulfide (AVS) with significant correlation between water content (W/C) and COD. A contour of spatial distribution indicated higher organic pollution at the bottom of ascidian, Stylea clava, cultural waters. Most of metals contents was not exceeded the NOAA's effect range-low (ERL). Estimated enrichment factor (EF) ranging 0.96-1.12 indicated that the sediment environment of the studied waters was relatively pristine from heavy metal pollution in spite of increased vessel traffics, so far.

• Journal of the Korean Electrochemical Society
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• v.7 no.3
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• pp.131-137
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• 2004

Sol-gel method which provides better electrochemical and physiochemical properties compared to the solid-state method was used to synthesize the material of $LiFe_yMn_{2-y}O_4$. Fe was substituted to increase the structural stability so that the effects of the substitution amount and sintering temperature were analyzed. XRD was used for the structural analysis of produced material, which in turn, showed the same cubic spinel structure as $LiMn_2O_4$ despite the substitution of $Fe^{3+}$. During the synthesis of $LiFe_yMn_{2-y}O_4$, as the sintering temperature and the doping amount of Fe(y=0.05, 0.1, 0.2)were increased, grain growth proceeded which in turn, showed a high crystalline and a large grain size, certain morphology with narrow specific surface area and large pore volume distribution was observed. In order to examine the ability for the practical use of the battery, charge-discharge tests were undertaken. When the substitution amount of $Fe^{3+}\;into\;LiMn_2O_4$ increased, the initial discharge capacity showed a tendency to decrease within the region of $3.0\~4.2V$ but when charge-discharge processes were repeated, other capacity maintenance properties turned out to be outstanding. In addition, when the sintering temperature was $800\~850^{\circ}C$, the initial capacity was small but showed very stable cycle performance. According to EVS(electrochemical voltage spectroscopy) test, $LiFe_yMn_{2-y}O_4(y=0,\;0.05,\;0.1,\;0.2)$ showed two plateau region and the typical peaks of manganese spinel structure when the substitution amount of $Fe^{3+}$ increased, the peak value at about 4.15V during the charge-discharge process showed a tendency to decrease. From the previous results, the local distortion due to the biphase within the region near 4.15V during the lithium extraction gave a phase transition to a more suitable single phase. When the transition was derived, the discharge capacity decreased. However the cycle performance showed an outstanding result.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.25-29
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• 2006

This study was carried out to investigate physiochemical properties and factors related with eating quality in the rice and paddy rice with different storage methods. As storage period was longer and temperature was higher, the b values of chromaticity and degree of fatty acid were increased, and the b value of room temp. was higher than that of low temp. In the varieties, the b value of Samcheonbyeo was the highest among varieties. also b value of Gancheokbyeo and Sae-gyehwabyeo were more increased than those of Dongjinbyeo and Hojinbyeo. Toyo meter values were significantly different according to storage temperature and period. Toyo meter values in storage of low temp. small decreased from 8 month after storages and that of loom temp. was severe decreased from 2 month after storages. In storage of low temp, Toyo meter values in storage of low temp. $(5{\sim}10^{\circ}C)$ was the lowest, and those of the early varieties were the most decreased. Degree of fatty acid of brown rice was increased from 2 month after storages and those of low temp. was severe increased. So, they made rice quality and eating quality to be deteriorated.

• Journal of Bio-Environment Control
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• v.21 no.1
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• pp.12-19
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• 2012

This research was performed to determine the appropriate daily last irrigation time to enhance the plant growth and the water and fertilizer use efficiencies in coir bag culture for tomato plant. The time to finish the daily irrigation was set by 1, 2, 3 and 4 hours before the sunset. The water content in the substrate was greatly affected by the last irrigation time. The earlier the last time, the greater the daily fluctuation of water contents in the substrate. The daily irrigation times were not affected by using irrigation management system controlled by drainage electrodes or the physiochemical properties of coir. The growth characteristics were not significantly different among the treatments. The highest marketable yields were obtained in the treatment finishing two hours before sunset, and the lowest yields were obtained in the the treatment finishing 4 hours before sunset. Based on the result from surveying quantity of irrigated water for 128 days of the experiment period, the water and fertilizer use efficiencies were lowest in the treatment finishing 4 hours before sunset, and the highest in the treatment finishing 2 hours before sunset. In terms of plant growth, yields, water and fertilizer use efficiencies, 2 hours before sunset treatment was determined as the most economical and desirable irrigation schedule.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.4
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• pp.514-519
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• 2011

Takju was manufactured using 150 g Rosa rugosa Thunb. (Haedanghwa) and two different preparations of 3,000 g each of cooked and uncooked rice. Nuruk (150 g) and yeast (60 g) were inoculated into both mixtures for fermentation, and physiochemical changes were investigated during 14 days of fermentation. The final brix value, pH, and ethanol concentration of Haedanghwa (uncooked rice Takju) were $13.0^{\circ}$Bx, 4.3, and 11.8%, respectively, whereas those of Haedanghwa (cooked rice Takju) were $14.0^{\circ}$Bx, 4.6, and 14.4%, respectively. Lactic and acetic acid levels in Haedanghwa (uncooked rice Takju) were significantly higher than those in Haedanghwa (cooked rice Takju) (p<0.05). The level of ${\gamma}$-amino-n-butyric acid in Haedanghwa Takju (uncooked rice) was twice than that of Haedanghwa Takju (cooked rice). Our results demonstrate that the use of uncooked rice in the preparation of Takju may help improve the taste and function of the final product.

• Food Science and Preservation
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• v.16 no.3
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• pp.311-316
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• 2009

Changes in physiochemical properties and polyphenol activities of wine fermented with apples and Rosa rugosa Thun were investigated. To this end, four different mixing ratios of apple and R. rugosa, including R. rugosa:apple 2:1 (Apple 33), R. rugosa:apple 1:2 (Apple 67), R. rugosa:apple 1:5 (Apple 83), and apple alone (Apple 100), were prepared and fermented by Saccharomyces bayanus for 14 days at $24^{\circ}C$ with a further 14 days of post-fermentation at $20^{\circ}C$. The final ethanol content ranged from 8.2.10.2%, with no significant difference between the four groups after fermentation and post-fermentation. Final Brix, pH, and total acidity of the four samples ranged from 7.1.7.5 Brix, pH 3.85.4.07, and acidity 0.73.1.19%. As the proportion of R. rugosa increased, the anthocyanin content and color intensity of wine also increased, whereas the free amino acid concentration decreased.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.3
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• pp.266-276
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• 2020

The purpose of this study was to compare the remineralization effect of 38% silver diamine fluoride (SDF) and 5% sodium fluoride (NaF) varnish on artificially induced enamel caries. The present study standardized the physiochemical characteristics of the tooth structure using bovine teeth, realized the wash-off action of agents using a saliva, reproduced an environment similar to mouth through pH-cycling, and comparatively assessed the remineralization effect of 38% SDF and 5% NaF varnish in a non-destructive method using micro-CT. And the remineralized enamel surface structure was analyzed by scanning electron microscopy (SEM) and energy dispersive X-Ray spectroscopy (EDS). In both SDF and NaF varnish, mineral density (△Hounsfield unit value) and the volume of enamel restored to normal mineral density through remineralization gradually increased with time. And the SDF showed a much higher level of increase in mineral density at all depths and remineralized volume than NaF varnish. According to SEM analysis, the surface roughness decreased in the order of artificial saliva, NaF varnish and SDF. In addition, EDS analysis showed that silver ion was precipitated on the enamel surface in SDF group. In conclusion, SDF had a greater remineralization effect than NaF varnish on demineralized enamel.

• The Korean Journal of Food And Nutrition
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• v.25 no.1
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• pp.9-16
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• 2012

The purposes of this study were to develop value-added sauce(ketchup) products with Korean advanced chile peppers (Capsicum annuum L.), determine their physicochemical characteristics, and conduct a sensory evaluation. American chile ketchup products were collected from American local favorites and analyzed based on their compositions. The Korean chile ketchup contained tomato paste(37.5%), Korean chile pepper(14.1%), sugar(14.8%), vinegar(14.1%), garlic(8.5%), herbs, plum extract, and oligosaccharide. Its physiochemical analysis showed: moisture $59.61{\pm}0.28%$, crude protein $2.18{\pm}0.11%$, crude lipid $1.99{\pm}0.04%$, crude ash $9.26{\pm}0.13%$, crude carbohydrate $26.97{\pm}0.48%$, reducing sugar $35.19{\pm}0.97%$, salt $3.04{\pm}0.04%$, acidity $2.22{\pm}0.01%$, pH $3.7{\pm}0.01$, and $^{\circ}brix\;36.3{\pm}0.14$. Korean chile ketchup showed higher overall acceptability compared to American local favorite chile ketchup. This result suggests the possibility for replacing chile ketchup products imported from foreign countries(USA and Europe).

• Journal of Korean Neurosurgical Society
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• v.63 no.6
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• pp.698-706
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• 2020

Objective : To study the physiochemical characteristics of podophyllotoxin (PPT) conjugated stearic acid grafted chitosan oligosaccharide micelle (PPT-CSO-SA), and evaluate the ability of the potential antineoplastic effects against glioma cells. Methods : PPT-CSO-SA was prepared by a dialysis method. The quality of PPT-CSO-SA including micellar size, zeta potential, drug encapsulation efficiency and drug release profiles was evaluated. Glioma cells were cultured and treated with PPT and PPT-CSO-SA. The ability of glioma cells to uptake PPT-CSO-SA was observed. The proliferation of glioma cells was determined by 3-[4, 5-dimethyl-2-thiazolyl]-2, 5-diphenyl-2H-tetrazolium bromide (MTT) assay. The apoptosis and morphology of U251 cells were observed by 4',6-Diamidino-2-phenylindole dihydrochloride (DAPI) dye staining. Cell cycle analysis was performed by flow cytometry. The migration ability of U251 cells was determined by wound healing test. Results : PPT-CSO-SA had nano-level particle size and sustained release property. The encapsulation efficiency of drug reached a high level. The cellular uptake percentage of PPT in glioma cells was lower than that of PPT-CSO-SA (p<0.05). The inhibitory effect of PPT-CSO-SA on glioma cells proliferation was significantly stronger than that of PPT (p<0.05). The morphologic change of apoptosis cell such as shrinkage, karyorrhexis and karyopyknosis were observed. The percentage of U251 cells in G2/M phase increased significantly in the PPT-CSO-SA group compared with PPT group (p<0.05). Compared with the PPT group, the cell migration ability of the PPT-CSO-SA group was significantly inhibited after 12 and 24 hours (p<0.05). Conclusion : PPT-CSO-SA can effectively enhance the glioma cellular uptake of drugs, inhibit glioma cells proliferation and migration, induce G2/M phase arrest of them, and promote their apoptosis. It may be a promising anti-glioma nano-drug.

• Journal of Animal Science and Technology
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• v.52 no.5
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• pp.435-440
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• 2010

Whey protein concentrate (WPC) is widely used to increase the nutritional and functional properties of food. In this study, the physiochemical and functionality of WPC-30 hydrolysates were examined to evaluate the possibility of application in the food industry. The WPC-30 was manufactured using ultrafiltration and spray-drying, and then hydrolyzed with proteolytic enzyme including alcalase, flavourzyme, nuetrase and protamex. Enzymatic hydrolysis had a significant influence on the physicochemical properties as evident from the increased foaming capacity, solubility. Alcalase caused highest protein hydrolysis (3.26%) and the bitterness. Foaming capacity was largest in WPC-30 hydrolysate treated with flavourzyme. Protein solubility at various levels of pH was highest in protamex-treated WPC-30 hydrolysate. However, the solubility of WPC-30 hydrolysates was significantly improved in alkaline condition than in acidic and neutral conditions. The study revealed that spray dried enzyme modified WPC can be used in various functional food.