• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.271-278
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• 2006

We used polymers of alternating cationic and anionic nature to build up shells on fiber surfaces, strengthen the worn-out fibers and improve paper properties made from such fibers. OCC and ONP pulps were either dipped or salted out in the cationic polyallylamine, polyacrylamide and starch solutions. After centrifugal drying, these were followed by treatments in anionic polyacrylic acid, poly-acrylamide, and starch solutions, respectively. The shell-enhanced fibers were formed into handsheets and their physical properties evaluated. The results show that building multiple shells on worn-out fiber surfaces can strengthen the fibers and paper. The simpler and more practical impregnation-centrifuging treatment provided the desired effects, whereas salting out the polymers produced somewhat superior fibers. The latter process, were impractical, however. The first pair of polymeric shells imparted marked strength improvement, whereas later layers had diminishing efficacies. Overall, the methods can improve fiber quality, attaining paper strength requirements without resorting to expensive measures. Alternate cationic polymer and filler powders were also deposited on fiber surface based on the micriparticle system in an anticipation of stiffness gains. Platy minerals, such as montmorillonite, bentonite, sericite, clay and talc were added following cationic PAM. After dewatering of polymer-pigment shelled fiber of one to 3 pairs of layers, handsheets either calendered or uncalendered were evaluated. The results indicate that regardless of calendaring, stiffness of the handsheets did not improve appreciably while certain other strength properties showed gains. We also attempted the novel starch gel filler addition method wherein tapioca starch and filers (PCC, sericite or clay) were mixed at high solids content of 50% and cooked until gelatinized. The filled handsheets were dried under various conditions and then tested for their properties. Improvements in strengths of modified filled paper were observed.

• Membrane Journal
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• v.29 no.2
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• pp.96-104
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• 2019

The purpose of this paper is whether or not the in-situ restoration of the reverse osmosis (RO) membranes which its membrane function is lost is possible. The damaged RO membranes are double coated through the salting-out method by the poly(styrene sulfonic acid) sodium salt as the cationic exchange polymer and the polyethyleneimine as the anionic exchange polymer and also conducted the opposite order of the coating materials. And according to the concentration, time and ionic strength, the flux and rejection are measured for the coated membranes. Then the best coating condition is to apply for the RO membrane module of the household water purifier to know the possibility of the in-situ restoration for the commercial module. When the condition of the PEI 30,000 ppm (IS = 0.1)/PSSA 20,000 ppm (IS = 0.7) is applied, the rejection was enhance from 69% for the damaged module to 86% (90% for the pristine module).

• Journal of Environmental Science International
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• v.27 no.11
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• pp.1095-1104
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• 2018

The adsorption characteristics of bisphenol A (BPA) were investigated using activated carbon based on waste citrus peel (which is abandoned in large quantities in Jeju Island), denoted as WCP-AC, and surface-modified with various $P_2O_5$ concentrations (WCP-SM-AC). Moreover, coconut-based activated carbon (which is marketed in large amounts) was surface-modified in an identical manner for comparison. The adsorption equilibrium of BPA using the activated carbons before and after surface modification was obtained at nearly 48 h. The adsorption process of BPA by activated carbons and surface-modified activated carbons was well-described by the pseudo second-order kinetic model. The experimental data in the adsorption isotherm followed the Langmuir isotherm model. With increasing $P_2O_5$ concentration (250-2,000 mg/L), the amounts of BPA adsorbed by WCP-SM-AC increased till 1,000 mg/L of $P_2O_5$; however, above 1,000 mg/L of $P_2O_5$, the same amounts adsorbed at 1,000 mg/L of $P_2O_5$ were obtained. With increasing reaction temperature, the reaction rate increased, but the adsorbed amounts decreased, especially for the activated carbon before surface modification. The amounts of BPA adsorbed by WCP-AC and WCP-SM-AC were similar in the pH range of 5-9, but significantly decreased at pH 11, and increased with increasing ionic strength due to screening and salting-out effects.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.1
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• pp.1-8
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• 2021

In order to develop value-added low-salt fermented seafood with a long shelf-life, we prepared seasoned low-salt fermented Mideoduck (Styela clava) supplemented with fermentation alcohol (SME). The SME was produced by washing and dewatering shelled Mideoduck, followed by cutting and salting for 24 h at 0℃. The salted Mideoduck was seasoned and fermented with ingredients, including garlic, ginger, monosodium glutamate, red pepper, sesame, sorbitol and sugar, for 7-8 days at 0℃. After adding 3-5% fermentation alcohol, the Mideoduck was packed in a polyester container. The salinity, volatile basic nitrogen, and amino nitrogen content of the SME was 4.5%, 20.9 mg/100 g and 92.0 mg/100 g, respectively. In comparison with the control, the addition of 3-5% fermentation alcohol showed inhibitory effects of decreased freshness, texture degradation, and growth of residual bacteria. Additionally, the SME had good storage stability and organoleptic qualities when stored at 4±1℃ for 40 days. Therefore, it is suitable for commercialization as a seasoned low-salt fermented product with a long shelf-life. The total amino acid content of the SME was 11,774.5 mg/100 g, majorly comprising glutamic acid, aspartic acid, lysine, arginine, and leucine, and the free amino acid content was 506.4 mg/100 g, majorly comprising hydroxyproline, taurine, and glutamic acid.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.178-178
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• 2020

본 연구에서는 벼 생육시기별로 염수 관개가 벼 작물에 미치는 생육 영향정도(민감도)를 평가하기 위하여 벼 재배실험(포트실험)을 수행하였다. 벼 재배실험은 일반 논토양(삼광벼)과 간척 논토양(신동진벼)을 대상으로 하였고, 벼 생육시기는 이앙기~활착기, 활착기~유수형성기, 유수형성기~수잉기, 수잉기~출수기, 등숙기의 5단계로 구분하였다. 벼 재배는 3반복 실험을 위해 총 126개의 포트(Φ215×Φ170×210mm(H))를 조성하여 5월 20일에 1주 3본으로 이앙을 하였다. 물 관개방식은 생육시기별로 염도를 1,000, 1,500, 2,000, 2,500 ppm으로 조절한 각각의 염수를 관개하고, 그 이외의 기간에는 담수(지하수)를 관개하였다. 벼 생육시기별로 염수 관개에 의한 벼 생육에 대한 민감도를 평가하고자 벼의 초장, 분얼수, 수확량을 조사하였다. 간척 논토양에서 초장, 분얼수는 생육초기인 이앙기의 염수에 의해 가장 민감하게 영향을 받는 것으로 나타났고, 수확량은 이앙기, 분얼기, 유수형성기 순으로 민감하게 영향을 받는 것으로 나타났다. 일반 논토양에서는 초장, 분얼수는 생육시기에 따른 염수관개에 의한 영향이 크지 않았으며, 수확량은 염분농도에 관계없이 이앙기, 분얼기, 유수형성기 순으로 염수에 의해 민감하게 영향을 받는 것으로 나타났다. 이러한 결과는 다수의 선행연구(Hassen Ebrahimi 등, 2011)의 벼 생육기인 분얼기, 유수형성기의 염수 관개가 수확량에 가장 많은 영향을 받는 결과와 일치하였다. 일반 논토양과 간척 논토양 모두 이앙기, 분얼기, 유수형성기 순으로 염수 관개에 민감한 영향을 나타내고 있으며, 특히 염분 배경농도가 높은 간척토양은 저농도의 염수에서도 민감한 반응을 보이고 있는 것으로 나타나, 벼 생육초기의 관개용수 염도관리는 매우 중요하다고 판단된다.

• Journal of the Korean Society of Food Culture
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• v.25 no.1
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• pp.61-69
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• 2010

This study was carried out to investigate the effects of various kinds of commercial salts, including sun-dried (Korea), purified, and traditional salts on the chemical and sensory properties and growth of microorganisms involved in kimchi fermentation. Kimchi was prepared by salting in 10% NaCl solution for 2 hours followed by addition of other spices and fermentation at $20^{\circ}C$. The decreases in pH suggested that kimchi fermentation can be classified into 3 steps: initial, intermediate, and final stages. In texture analysis, the hardness and fracturability of traditional salt kimchi were higher than those of regular kimchi. From the sensory evaluation test for kimchi, sensory scores were high for traditional salt addition, especially taste, overall preference and texture. Among various microorganisms related to kimchi fermentation, the growth of Leuconostoc mesenteroides, Lactobacillus plantarum, Pichia membranaefaciens and Escherichia coli were examined. Based on the conditions of kimchi fermentation, a 2% and 5% concentration of each salt were studied. Also, the conditions of the cultures at $37^{\circ}C$ were examined. There was no considerable difference in the growth of Leuconostoc mesenteroides, Lactobacillus plantarum, Escherichia coli in the different kinds of salts. However, the growth of Pichia membranaefaciens was strongly inhibited by a 5% concentration of traditional salt during incubation at $37^{\circ}C$.

• Journal of Dairy Science and Biotechnology
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• v.33 no.3
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• pp.215-221
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• 2015

This study aimed to establish the optimum culture conditions for Mozzarella cheese by using Streptococcus macedonicus LC743, a strain selected for its immunomodulatory activity. For process optimization, 1.0% and 2.0% strain was inoculated and incubated at $32^{\circ}C$ and $35^{\circ}C$, respectively. The general components, bacterial count, total solids, yields, and immunomodulatory activity of the Mozzarella cheese were investigated. When the strain was inoculated at 2.0% and incubated at $32^{\circ}C$, the product quality and immunomodulatory activity was optimal and required minimal processing time. Therefore, 2.0% of S. macedonicus LC743 starter culture was added to milk at $32^{\circ}C$, after pasteurization at $63^{\circ}C$ for 30 min, and agitated for 4~5 min after addition of $230{\mu}L/kg$ of rennet. Curd was made by setting the milk 25~35 min after addition of 0.01~0.02% calcium chloride. The curd was cut at 0.1~0.12% acidity (81 min later) and after heating the cheese to up to $43^{\circ}C$. Whey was removed at an acidity of 0.17~0.18% by agitation for 53 min. Next, cheddaring for 210 min up to an acidity of 0.6~0.65%, stretching at $72{\sim}75^{\circ}C$, and molding at $65{\sim}70^{\circ}C$ were performed, and the product was allowed to cool down to $5^{\circ}C$. Salting was done with a solution of $18{\sim}20^{\circ}B{\acute{e}}$ at $12^{\circ}C$ for 20 min and drying occurred at 80~90% relative humidity at $10^{\circ}C$ for 2~3 days.

• Journal of the Korean Chemical Society
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• v.47 no.4
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• pp.363-369
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• 2003

Selenized yeast (Se yeast) containing $0.1{\%}$(w/w) of selenium was obtained when the yeast was incubated at a selenium concentration of 1$1.14{\times}10_-3 M$ in rich medium. After washing several times, the inorganic selenium on the cell wall was confirmed with MBRT. There was no indication of inorganic selenium on the cell wall when the blue color in MBRT was stayed for 15 minutes. The selenized yeast was sonicated, then the selenium contained protein was obtained after salting out by ammonium sulfate at the concentration $80{\%}$ saturation. The seven protein bands were seperated by SDS-PAGE and the selenium concentration in protein was measured by ICP-AES. Analytical data showed that the large expressed protein band contained a relatively large amount of selenium. The proteins of the 47kDa was contained the concentrations of 69.5 ${\mu}$ Se/g of most many content. The protein (47 kDa) was seperated from PVDF membrane by tank-electroblotting. The isolated protein was hydrolyzed under acid condition and reacted with PITC. The derivatives of amino acids were analyzed by HPLC and compared with the data obtained from regular yeast. The resulting selenium-yeast was analyzed with the selenomethionine concentration of $2{\%}$ comparaed with general amino acids. The goal of this study is to analyze the selenium concentration in protein bands and measure the degree of biotransformation of selenomethionine in a specific protein.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.2
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• pp.240-248
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• 1996

To clarify the potentiality of sea cucumbers as dietary food, the effects of those glycoprotein on dietary proteins and physicochemical properties of those proteins were studied. Crude glycoprotein was efficiently extracted using 20mM sodium phosphate beffer(pH 7.0) and by salting out with 80% ammoniym sulfate saturation. The fractions obtained through the DEAE-cellulose ion exchange chromatography was identified as glycoprotein by Schiff's reagent and SDS polyacrylanide gel electro-phoresis. The yields of each glycoprotein from the three kinds of sea cucumbers were 0.814(red), 0.184(blue) and 0.232(black) and the molecular weights of the glycoproteins subunits were ranged from 20,000 dalton(blue and black) to 29,000 dalton(red), respectively. The electrophoretic patterns of the glycoprotein isolates were similar to each other and any significant difference in amino acid pattern was observed. Predominant arnino scids were Asx(aspartic acid and asparagine) and Glx(glutamic acid and glutamine) ; in contrast, histidine and methionine were below 2% as compared to total amino acids. water holding capacities of the glycoprotein isolates from red, blue and black cucumbers were equally 100% and emulsion activities ranged from 53% to 64%. In addition the emulsion stabilities were 7.04, 1.37 and 2.44, respectively. In vitro digestibility of some proteins(casein, SPI and squid) was decreased as increasing the level of the freeze dried sea cucumber powder and glycoprotein isolates. But squid protein was not affected.

• Korean Journal of Environmental Agriculture
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• v.20 no.4
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• pp.244-251
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• 2001

This study was performed to investigate the recovery efficacy of 2-methylisobomeol (2-MIB) and Geosmin, odor contaminants produced by algae, by pretreatment techniques, and also to investigate both adsorption characteristics and removal efficiency to get some information for the effective removal of 2-MIB and Geosmin by batch experiments. In pretreatment experiments, the best recovery efficiency of both odorants at 0.2 and $2\;{\mu}g/L$ in raw water was 30 mL of sampling size, 9 g NaCl for salting out headspace of sampling phase and 40 minutes of adsorption. At the best condition, the recovery efficiency of 2-MIB was 85% at $0.2\;{\mu}g/L$ and 95% at $2\;{\mu}g/L$, whereas the efficiency of Geosmin was lower than that of 2-MIB : 61% at $0.2\;{\mu}g/L$ and 81% at $2\;{\mu}g/L$. In batch experiments, the removal efficiency of the Geosmin and 2-MIB by adsorbents using distilled water were increased in comparison with raw water, the efficiency in raw water was little different by their concentrations. When these results were applied to the Freundrich adsorption isotherm, the K value of 2-MIB for zeolite, coal activated carbon, and coconut activated carbon was 0.671, 1.811, and 1.340, respectively, and the value of Geosmin was 0.6125, 1.771, and 1.5191, respectively. Thus the adsorption efficiency of 2-MIB and Geosmin was in the order of zeolite, coconut activated carbon, coal activated carbon.