• Journal of the Society of Disaster Information
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• v.13 no.3
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• pp.332-339
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• 2017

In the case of aged structures, the information of the structure is often lost after the completion of construction, and there is a great difficulty in predicting the durability life of the structure due to the lack of information on concrete formulations. In this study, the durability of concrete specimens was evaluated by various field and indoor test methods based on the core specimens collected from the field, and the durability life of the concrete structures was predicted by using the FEM analysis technique.As a result, the neutralization rate coefficient was $5.38E-6(cm^2/day)$ and the rate of progress was low. And the possibility of complex deterioration due to carbonation and salting was found to be very low.

• Applied Biological Chemistry
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• v.35 no.5
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• pp.399-403
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• 1992

The amounts of salt diffused into radish after immersing in various concentrations of salt solution at different temperatures were measured and the changes of radish texture by the salt diffusion were estimatedwith the viscoelastic constants of a 3 element solid model determined by a stress relaxation test. While the amount of salt diffused throught radish was increased with increasing the salt concentration and soaking temperature, the istantaneous stress, equilibrium elastic solid and viscoelastic constants of radish were decreased. Also the degree of stress relaxation and equilibrium elastic solid approached the same or zero values, as salt concentration was further increased. Viscoelstic constants as well as salt diffusion were more influenced by lower salt concentration with increased temperatures.

• Membrane Journal
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• v.25 no.5
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• pp.391-397
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• 2015

The porous support polyvinylidene fluoride (PVDF) with a salting out based on the hollow fiber membrane polyethyleneimine (PEI) and polyvinylsulfonic acid (PVSA) by coating with by phase separated and pressurization (PSP) method to produce a multilayer membrane. The resulting membranes were characterized under the various conditions, such as the heat treatment temperature, coating concentration, feed concentration, cross-linking time and cross-link agent concentration in terms of flux and rejection rate for NaCl 100 ppm solution at 4 atm. The best results were PEI 20,000 ppm and PVSA 1,000 ppm, PEI 15% with a 2% malic acid aqueous solution coated by PSP method the hollow fiber membrane heat-treated for 1 minute showed flux 24.3 LMH, the rejection of 82.1%.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.5
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• pp.808-812
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• 1998

Melania snail(Semisulcopira bensoni) is used as ingredient in Korean traditional soup and nutritional foods. Generally, lipoxygenase in several food products may produce off-flavors during their processing and storage. Therefore, the inactivation of lipoxygenase is required to make the better extracts from Melania sanil. Also, the quality on freshness of Melania snail may be evaluated by lipoxygenase activity. The lipoxygenae activity was the highest at 40~60% saturation among several concentrations in salting-ouot saturated solution of ammonium sulfate. The partial purification of lipoxygenase was successfully obtained by Sephacryl S-200 gel chromatography. The first peak among three peaks for protein determination showed the highest activity of lipoxygenase in 13~16 fractions among 100 fractions. The highest peak of lipoxygenase activity by ion exchange chromatography was shown at 0.1M NaCl. In the purification step, the specific activity was 20.8U/mg and activity yield was 19.8%. The optimum pH and temperature were pH6.0~8.0 and 3$0^{\circ}C$, respectively. Molecular weight of the lipoxygenase was estimated about 35kDa by SDS-PAGE.

• Membrane and Water Treatment
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• v.10 no.6
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• pp.451-460
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• 2019

Thin film composite membranes incorporated with nano-sized hydrophilic zeolite -A were successfully prepared via interfacial polymerization (IP) on porous blend PES/PAN support for water desalination. The thin film nanocomposite membranes were characterized by SEM, contact angle and performance test with 7000 ppm NaCl solution at 7bar. The results showed that the optimum zeolite loading amount was determined to be 0.1wt% with permeate flux 29LMH.NaCl rejection was improved from 69% to 92% compared to the pristine polyamide membrane where the modified PA surface was more selective than that of the pristine PA. In addition, there was no significant change in the permeate flux of the thin film nanocomposite membrane compared with that of the pristine PA in spite of the formation of the dense polyamide layer. The stability of the polyamide layer was investigated for 15 days and the optimized membrane presented the highest durability and stability.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.6
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• pp.841-848
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• 2021

To develop a value-added low-salt fermented seafood with a long shelf-life, we prepared seasoned low-salt fermented Omandungi Styela plicata supplemented with fermentation alcohol (SOE). The SOE was produced by washing and dewatering shelled Omandungi, followed by cutting and salting for 24 h at 0±1℃. The salted Omandungi was seasoned and fermented with garlic, ginger, monosodium glutamate, red pepper, sesame, sorbitol, and sugar, for 7-8 days at 0±1℃. After adding 3-5% fermentation alcohol, the seasoned fermented Omandungi was packed in a polyester container. The salinity, volatile basic nitrogen content, and viable cell count of SOE were 4.8%, 22.1-22.2 mg/100 g, and (1.2-1.9)×10³ CFU/g, respectively. Compared with the control, addition of 3-5% fermentation alcohol inhibited the decrease in freshness, texture degradation, and growth of residual bacteria. Additionally, the SOE showed good storage stability and organoleptic qualities when stored at 4±1℃ for 40 days. The total amino acid content of SOE was 2,186.0 mg/100 g, mainly comprising glutamic acid, aspartic acid, lysine, and phenylalanine. The free amino acid content was 189.0 mg/100 g, and mainly included taurine, glutamic acid, methionine, alanine, and proline.

• Analytical Science and Technology
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• v.35 no.5
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• pp.197-204
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• 2022

A gas chromatography-mass spectrometric method was developed for determining 5-chloro-2-methyl-4-isothiazolin-3-one (CMIT), 2-methyl-4-isothiazolin-3-one (MIT), 1,2-benzisothiazolin-3-one (BIT), 3-iodo-2-propynyl butyl carbamic acid (IPBC) and benzoic acid (BA) in household products. A 0.5 g sample was placed in a test tube and dissolved with 5 mL water, 5 mL methylene chloride and 1.0 mL methanol. The solution was extracted by ultra-sonication followed by mechanical shaking using the salting out effect. Under the established condition, the lowest quantification limits of all analytes were in the range of 0.04-10 mg/kg and their relative standard deviations were less than 8.0 %. The method was used to analyze 10 household products. As a result of analyzing 10 household products, MIT was detected in the range of 1.2-3.5 mg/kg in 3 of 10 samples, CMIT was detected in the range of 2.6-8.2 mg/kg in 3 of 10 samples, and BA was detected in the range of 5.0-15 mg/kg in 4 of 10 samples. Meanwhile, BIT and IPBC were not detected in any of the products. It has been shown that this method can be used for the simultaneous determination of biocides with various physical and chemical properties in household products.

• Analytical Science and Technology
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• v.20 no.1
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• pp.70-77
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• 2007

Twelve chlorophenols (CPs) were extracted by liquid phase microextraction (LPME) from the industrial waste-water and analyzed by GC/MS. To establish the optimal conditions, species of extraction solvent, sample amount, pH of sample, salting out effect, a number of sampling and plunger movement speed were investigated. As a result, the linearities of calibaration curves ranged from 0.9913 to 0.9999, while LODs and LOQs were from 0.05 to 10.0 ng/mL except 2,3,4,5-tetrachlorophenol and pentachlorophenol. Using this method, 4-chloro-3-methylphenol confirmed from waste water at the concentration of 784 ng/mL. The method can be applicable to detect chlorophenols from industrial waste-water.

• Journal of the Korean Applied Science and Technology
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• v.34 no.2
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• pp.289-295
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• 2017

The International Maritime Organization (IMO) in accordance with the regulations with respect to the combustion gases, such as NOx, SOx generated by the marine engine. The combustion gases must be equipped with a device to reduce emissions from all ships passing through the Baltic SECAs. In Korea, the International Maritime Organization (IMO) and the development of a device for NOx, SOx reduction. Scrubber is used in the ammonia water and the Urea solution in the waste water. The waste water containing ammonium nitrate and ammonium sulfate, react of the NOx and SOx gas. In this study, the recovery of by-product, which contains the waste water was used as an organic solvent extraction method of salting out. Ammonium nitrate and ammonium sulfate, the recovery process. A qualitative analysis of the collected by-product FT-IR analysis. Through the elemental analysis and SEM-EDS, characteristic evaluation was performed with an impurity.

• Preventive Nutrition and Food Science
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• v.8 no.3
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• pp.270-277
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• 2003

In order to enhance the firmness and shelf-life of kimchi, as well as to increase the content of well-absorbed digestible calcium, the effect of calcium lactate (CaL) treatment of salted Chinese cabbage on pH, tit ratable acidity, total microbes, lactic acid bacteria, alcohol insoluble substance (AIS) content, firmness, mineral content and tissue structure were investigated. Treatment with the Cal solution increased pH and decreased titratable acidity, which was more pronounced at higher concentrations. The edible period evaluated by pH was 7～8 days for non-treated kimchi, 10 days for 1 % treated kimchi, 15 days for 2% treated kimchi and 20 days for 3% treated kimchi. Total microbes were reduced, but lactic acid bacteria counts were higher in the treated group. CaL treated kimchi showed higher AIS content and firmer texture, which was more conspicuous in the 2 and 3% CaL treated groups. Calcium content in kimchi fermented for 15 days was 40.75～41.53 mg%, which is 42～45% higher than that in the control group. The sodium content was 23～54% less in the treated groups. The epidermis and vascular bundle tissue of kimchi fermented for 15 day was damaged more severely in the control group than in the treated group. CaL treated kimchi has a crispier taste and the development of sour taste was delayed. Therefore, addition of CaL can produces a kimchi with high calcium as well as superior texture and shelf-life, when adjusting the concentration according to the fermentation periods.