• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.380-386
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• 2011

Tip burn has been reported as one of the most serious physiological disorder in Chinese chives (Allium tuberosum Rottl.) cultivated in plastic film house. In this study, a physiography and chemical properties of 132 plastic film house soils were investigated to elucidate factors affecting tip burn symptom. Also influence of soil properties on tip burn was statistically determined by path analysis and association analysis including a chi-square test or logistics analysis. Probability distribution of inorganic aqueous species, such as ammonia (g) was calculated using MINTEQ program. Soil order and chemical properties, especially pH, exchangeable calcium and inorganic nitrogen, showed a significant relationship with tip burn of Chinese chives. Tip burn symptoms occur mainly in an alkaline soil classified as Alfisols. Result of linear regression and path analysis exhibited that formation of ammonia (g) from soil solution depend upon soil pH and were associated with ammonium resulting from soil organic matter or nitrate. These results indicate that tip burn symptom of Chinese chives is directly affected by ammonia gas originated from alkaline soil condition.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.480-486
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• 2002

Six strains of intestinal pathogenic bacteria were inoculated into kimchi at the preparation time, and the influence of kimchi fermentation on the growth of these pathogenic bacteria was investigated. The population of coliform bacteria in the kimchi raw materials, and its changes in the kimchi sample during fermentation were also determined. Among the raw materials, highest populations of coliform bacteria were detected in ginger and green onion, followed by Chinese cabbage, red pepper, and garlic. Populations of pathogenic bacteria (inoculated strains) and coliform bacteria in kimchi decreased as pH decreased with fermentation. Coliform bacteria disappeared at pH 3.9 in Chinese cabbage kimchi samples. Clostridium perfringens ATCC 13124, Listeria monocytogenes ATCC 19111, Salmonella typhimurium KCTC 1625, Staphylococcus aureus KCTC 1621, Vibrio parahamolyticus ATCC 27519, and Escherichia coli O157 H:7 ATCC 43894 were not detected at pH values less than 4.1, 3.7, 3.8, 3.8, 3.7, and 3.7 in Chinese cabbage kimchi, and at pH values less than 4.5, 4.0, 4.2, 4.2, 4.2 and 4.1 in mustard leaf kimchi, respectively. The juice of mustard leaf and allyl isothiocyanate exhibited high antimicrobial activities on the pathogenic bacteria, whereas the lowest on lactic acid bacteria. These results indicated that fermentation is useful to improve the safety of kimchi, and the antimicrobial effect of mustard leaf kimchi is mainly due to the major pungent compound of mustard leaf, allyl isothiocyanate.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.5
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• pp.732-739
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• 2009

Pig slurry is a good soil amendment not only because of its high organic matter content, but also because of its ability to provide various nutrients. The objective of this study was to estimate the influence of raw and processed pig slurry application on pot soil over chemical fertilizer and non-amended control soil. Change in the chemical parameters (pH, organic matter (OM), organic carbon (OC), macro and micronutrients) and microbial mass of the treated soils were monitored over 30 to 90 days. Pot soil was treated with the recommended dose of pig slurry and chemical fertilizer, and was sampled after 30, 60 and 90 days of incubation. The least significanct difference (p<0.05) was observed on Fe, Cu, Zn, available P and K between treatments. All treatments increased N, P and K content and microbial mass of soil over control soil. Interestingly, no significant effects were detected on OM, OC, total bacteria, actinomycetes and fungi mass in soil irrespective of treatments given. However fungal and bacterial counts, as well as available nutrients, were found to be higher in processed slurry (PS)-treated soil compared to other soils. In general a significant correlation existed between the fungal count and OM, OC, Zn, T Kjeldahl N (TKN), available P and K of soil. A strong negative correlation was observed between pH and Fe in soil. This study clearly demonstrated that the use of processed manure as a fertilizer could be a key for sustainable livestock agriculture.

• Clean Technology
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• v.12 no.1
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• pp.37-44
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• 2006

The effectiveness of inorganic oxides (DT-30), anionic exchange resin (DT-60) and carbon absorbent (DT-80, DT-90) on the equilibrium and continuous separation characteristics and removal of cobalt, cesium and iodide ion in the waste water was investigated. As a result, DT-30, DT-80 or DT-90, and DT-60 showed excellent separation properties on the cesium, cobalt and iodide respectively. In the equilibrium experiment, the adsorption amount of cesium for DT-30 increased with temperature, but increasd largely with pH. In case of DT-80, adsorption of cobalt was depended on pH but was not influenced by temperature. In the continuous system by passing a heavy metal ion solution through the ion exchange tower, DT-30, DT-90 and DT-60 showed good separation characteristic for cesium, cobalt and iodide respectively. In this case, separation characterization of DT-30 on the cesium and of DT-60 on the iodide were better than that of DT-90 on the cobalt. From the experiment on the effect of impurities on the ion exchange characteristics, impurities such as surfactant and oil did not influence the efficiency of DT-90. In the mean while, ion separation capacity of DT-30 were decreased largely by impurities such as surfactant and oil. Also, surfactant had a strong influence on the effectiveness of DT-60. Accordingly, it turned out to be very important thing that impurities should be removed in the preprocessing stage.

• Korean Journal of Environmental Agriculture
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• v.36 no.4
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• pp.288-292
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• 2017

BACKGROUND: Silicon tetrachloride reacts with moisture in the atmosphere to generate hydrogen chloride, which affects the environment. Since silicon tetrachloride and its by-products are dispersed in the atmosphere in a short time after the silicon tetrachloride release into the atmosphere, it is difficult to directly assess the extent of environmental impact. In the present study, the exposure test of silicon tetrachloride or hydrogen chloride was examined in order to establish the criterion of the range affected by the silicon tetrachloride release, and the actual crops in the area exposed to silicon tetrachloride leakage were analyzed. METHODS AND RESULTS: For the experiment of exposure to silicon tetrachloride or hydrogen chloride, the leaves of red-pepper and corn were used in glass sealed containers. In the actual accident area, 59 samples from 10 different kinds of crops were collected. The pretreatment of the sample was performed by freezing and grinding, and then extracted using distilled water. The pH and concentration of chloride ($Cl^-$) ion of the extracted solution were measured using pH meter and ion chromatograph, respectively. CONCLUSION: Exposure to silicon tetrachloride caused visible damage, increasing the concentration of chloride ion, and decreasing the pH as well as hydrochloric acid. In the actual crops of the affected area, the tendency was the same as the result of the laboratory test, and the range of influence could be estimated through the concentration of $Cl^-$ ion over 2,000 mg/kg, and the correlation evaluation between the concentration of $Cl^-$ and pH. Therefore, the concentration of $Cl^-$ ion and the correlation between $Cl^-$ and pH would be considered as the factors to estimate the influence range of silicon tetrachloride release.

• Korean journal of food and cookery science
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• v.1 no.1
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• pp.18-26
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• 1985

The effect of 0.05% Sorbic acid on the Kimchi fermentation and stability of ascorbic acid were investigated at 23~$25^{\circ}C$. The results are as follows. 1. Kimchi with sorbic acid showed a higher pH and a lower total acidity in general, as compared with the control Kimchi. 2. Kimchi with sorbic acid contains more ascorbic acid for the fermentation period. Especially showed the higher hydro ascorbic acid than control Kimchi. 3. The Lacticacid bacteria isolated from Baechu Kimchi and Dongchimi are identifi-ed as Leuconostoc mesenteroides, Lactobacillus Plantarum, Lactobacillus brevis, Streptococcus faecalis, Pediococcus pentosaceus. 4. The effect of sorbic acid upon the growth of Lactic acid bacteria and acid prod-ucibility is found least in Lactobacillus Plantarum, and most in Leuconostoc mesenter-oides. 5. The changes of Lacticacid bacteria occured during Kimchi fermentation curbed Leuconostoc mesenteroides most of all in Baechu Kimchi and Dongchimi with sorbic acid, while the least influence was had on Lactobacillus plantarum. Expecially, yeast wae completely curbed. 6. A result of a sensory evaluation reveals that a better taste is derived from the control Kimchi, with a significant difference, in pH4~4.3, whereas from Kimchi with sorbic acia in pH 3.7~3.8.

• Molecules and Cells
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• v.23 no.1
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• pp.11-16
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• 2007

N,N-dimethyl-D-erythro-sphingosine (DMS) is an N-methyl derivative of sphingosine and an inhibitor of protein kinase C (PKC) and sphingosine kinase (SK). In the present study, we examined the effects of DMS on intracellular $Ca^{2+}$ concentration, pH, and glutamate uptake in human 1321N1 astrocytes. DMS increased intracellular $Ca^{2+}$ concentration and cytosolic pH in a concentration-dependent manner. Pretreatment of the cells with the $G_{i/o}$ protein inhibitor PTX and the PLC inhibitor U73122 had no obvious effect. However, removal of extracellular $Ca^{2+}$ with the $Ca^{2+}$ chelator EGTA or depletion of intracellular $Ca^{2+}$ stores with thapsigargin impeded the DMS-induced increase of intracellular $Ca^{2+}$ concentration. Pretreatment of cells with $NH_4Cl$ or monensin reduced the DMS-induced $Ca^{2+}$ increase. However, inhibition of the DMS-induced $Ca^{2+}$ increase with BAPTA did not influence the DMS-induced pH increase. DMS also inhibited glutamate uptake by the 1321N1 astrocytes in a concentration-dependent manner. It also increased intracellular $Ca^{2+}$ and pH in PC12 neuronal cells. Our observations on the effects of DMS on 1321N1 astrocytes and PC12 neuronal cells point to a physiological role of DMS in the brain.

• Textile Coloration and Finishing
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• v.19 no.4
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• pp.32-37
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• 2007

In this study, we have obtained the protein patterns using the membrane patterning of soft-lithography technique. The rapid detection of protein including bovine serum albumin (BSA) was resulted from the interaction with 1,3-bisdicyanovinylindane. For the proof of the interaction between BSA and dye, the UV-vis absorption spectra of BSA and dye were observed at 278 nm and 580 nm, respectively. As expected, the absorption spectrum of the interaction between BSA and dye was observed at 584nm. The absorption spectrum of the interaction was red-shifted. In addition, the optical images of the selectively reacted protein patterns showed the distinctive change of patterned color at different pH conditions. Because the dye has negative charges, the charge of BSA at different pH conditions could influence the interaction behavior between dye and BSA. Therefore, in the case of pH 7, the selectively patterned protein substrates obtained deep blue color pattern caused by electrostatic interaction between negative charges of the dye and positive charges of the BSA. However, in the case of pH 10, selectively patterned protein substrates obtained light blue color pattern because the electrostatic interaction was relatively lower than pH 7 due to the change of overall charge distribution of BSA.

• Bulletin of the Korean Chemical Society
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• v.34 no.11
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• pp.3444-3450
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• 2013

Three phase hollow fiber-liquid phase microextraction (HF-LPME), which is faster, simpler and uses a more environmentally friendly sample-preparation technique, was developed for the analysis of Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) in human urine. For the effective simultaneous extraction/concentration of NSAIDs by three phase HF-LPME, parameters (such as extraction organic solvent, pH of donor/acceptor phase, stirring speed, salting-out effect, sample temperature, and extraction time) which influence the extraction efficiency were optimized. NSAIDs were extracted and concentrated from 4 mL of aqueous solution at pH 3 (donor phase) into dihexyl ether immobilized in the wall pores of a porous hollow fiber, and then extracted into the acceptor phase at pH 13 located in the lumen of the hollow fiber. After the extraction, 5 ${\mu}L$ of the acceptor phase was directly injected into the HPLC/UV system. Simultaneous chromatographic separation of seven NSAIDs was achieved on an Eclipse XDB-C18 (4.6 mm i.d. ${\times}$ 150 mm length, 5 ${\mu}m$ particle size) column using isocratic elution with 0.1% formic acid and methanol (30:70) at a HPLC-UV/Vis system. Under optimized conditions (extraction solvent, dihexyl ether; $pH_{donor}$, 3; $pH_{acceptor}$, 13; stirring speed, 1500 rpm; NaCl salt, 10%; sample temperature, $60^{\circ}C$; and extraction time, 45 min), enrichment factors (EF) were between 59 and 260. The limit of detection (LOD) and limit of quantitation (LOQ) in the spiked urine matrix were in the concentration range of 5-15 ng/mL and 15-45 ng/mL, respectively. The relative recovery and precision obtained were between 58 and 136% and below 15.7% RSD, respectively. The calibration curve was linear within the range of 0.015-0.96 ng/mL with the square of the correlation coefficient being more than 0.997. The established method can be used to analyse of NSAIDs of low concentration (ng/mL) in urine.

• Restorative Dentistry and Endodontics
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• v.41 no.4
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• pp.246-254
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• 2016

Objectives: The aim of this investigation was to give insights into the impact of carbohydrate-electrolyte drinks on the likely capacity of enamel surface dissolution and the influence of human saliva exposure as a biological protective factor. Materials and Methods: The pH, titratable acidity (TA) to pH 7.0, and buffer capacity (${\beta}$) of common beverages ingested by patients under physical activity were analyzed. Then, we randomly distributed 50 specimens of human enamel into 5 groups. Processed and natural coconut water served as controls for testing three carbohydrate-electrolyte drinks. In all specimens, we measured surface microhardness (Knoop hardness numbers) and enamel loss (profilometry, ${\mu}m$) for baseline and after simulated intake cycling exposure model. We also prepared areas of specimens to be exposed to human saliva overnight prior to the simulated intake cycling exposure. The cycles were performed by alternated immersions in beverages and artificial saliva. ANOVA two-way and Tukey HDS tests were used. Results: The range of pH, TA, and ${\beta}$ were 2.85 - 4.81, 8.33 - 46.66 mM/L and 3.48 - $10.25mM/L{\times}pH$, respectively. The highest capacity of enamel surface dissolution was found for commercially available sports drinks for all variables. Single time human saliva exposure failed to significantly promote protective effect for the acidic attack of beverages. Conclusions: In this study, carbohydrate-electrolyte drinks usually consumed during endurance training may have a greater capacity of dissolution of enamel surface depending on their physicochemical proprieties associated with pH and titratable acidity.