• Korean Chemical Engineering Research
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• v.55 no.1
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• pp.115-120
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• 2017

In recent, it is worldwide issued that nanoscale science and technology as a solution have supported to increase the sensing performance in carbon nanotube based biosensor system. Containing material chemistry in various nanostructures has formed their high potentials for stabilizing and activating biocatalyst as a bioreceptor for medical, food contaminants, and environmental detections using electrode modification technologies. Especially, the large surface area provides the attachment of biocatalysts increasing the biocatalyst loading. Therefore, nano-scale engineering of the biocatalysts have been suggested to be the next stage advancement of biosensors. Here, we would like to study the electrical mechanism depending on the exposure methods (soaking or dropping) to the sample solution to the assembled carbon nanotubes (CNTs) on the gold electrodes of biosensor for a simple and highly sensitive detection. We performed various experiments using polar and non-polar solutions as sampling tests and identified electrical response of assembled CNTs in those solutions.

• Food Science and Preservation
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• v.6 no.3
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• pp.313-318
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• 1999

The Properties of rice flour and consumed electricity to make rice flour were compared among three different process ; 1. roll mill after soaking rice in water, 2. roll mill after tempering, 3. try pin mill. When rice was milled by roll mill and pin-milled after tempering for 10 hrs(TRPMR), consumed electricity and moisture content of rice flour were the least. Particle size of rice flour prepared with TRPMR was 87.4% of 100 mesh or more which was the highest number among the rice flour prepared using different processes. Gelatinization temperature of the rice flour was 63.2$^{\circ}C$ and was 1.3$^{\circ}C$ lower than that of rice flour prepared with other processes. Viscosity of the rice flour prepared by TRPMR was the least. Whiteness of the rice flour prepared by TRPMR was similar to that of wheat flour.

• Food Science of Animal Resources
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• v.24 no.3
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• pp.266-272
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• 2004

The objective of this study was to investigate the physicochemical characteristics of gelatin extracted from pork skin under soaking in various acid solutions (lactic acid, acetic acid, and citric acid). Gelatin sol was extracted at 8$0^{\circ}C$, frozen at -2$0^{\circ}C$ and lyophilized it for 3 days to be completely dried in freeze drying unit. In the evaluation of gelatin quality, gelatin soaked in citric acid showed higher L- and a-values than those of any other gelatin (p<0.05). Gelatin treated by acetic acid showed the highest gel strength, cohesiveness, and brittleness. The content of hydroxyproline amino acid in gelatin treated by acetic acid was larger than one of gelatin treated in lactic and citric acid in order. From the experimental results, the highest quality of gelatin in all of period, which was soaked in acetic acid and lactic acid, has a more good quality than gelatin soaked in citric acid.

• Korean Journal of Materials Research
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• v.19 no.7
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• pp.362-368
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• 2009

Ti scaffolds with a three-dimensional porous structure were successfully fabricated using powder metallurgy and modified rapid prototyping (RP) process. The fabricated Ti scaffolds showed a highly porous structure with interconnected pores. The porosity and pore size of the scaffolds were in the range of 66$\sim$72% and $300\sim400\;\mu$m, respectively. The sintering of the fabricated scaffolds under the vacuum caused the Ti particles to bond to each other. The strength of the scaffolds depended on the layering patterns. The compressive strength of the scaffolds ranged from 15 MPa to 52 MPa according to the scaffolds' architecture. The alkali treatment of the fabricated scaffolds in an aqueous NaOH solution was shown to be effective in improving the bioactivity. The surface of the alkali-treated Ti scaffolds had a nano-sized fibre-like structure. The modified surface showed a good apatite forming ability. The apatite was formed on the surface of the alkali treated Ti scaffolds within 1 day. The thickness of the apatite increased when the soaking time in a simulated body fluid (SBF) solution increased. It is expected that the surface modification of Ti scaffolds by alkali treatment could be effective in forming apatites in vivo and can subsequently enhance bone formation.

• Journal of Food Hygiene and Safety
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• v.28 no.1
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• pp.31-35
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• 2013

In this study, the pesticide residues of polished rice and brown rice were measured after washing and cooking process. The initial concentrations of isoprothiolane and fthalide were $7.134{\pm}0.03mg/kg$ and $2.024{\pm}0.04mg/kg$ for polished rice, and $17.941{\pm}1.41mg/kg$ and $6.413{\pm}0.19mg/kg$ for brown rice, respectively. After first washing process, the removal rates of isoprothiolane were 23.0% (polished rice) and 18.5% (brown rice). Also, the case of fthalide, the removal rates were 14.0% and 9.7%, respectively. The removal dose was increased, but the removal rate was decreased in proportion to the number of washing process, After the cooking process, the removal rates of isoprothiolane and fthalide were 66.0% and 79.0% (polished rice), and 88.7% and 92.9% (brown rice), respectively. The removal rate of isoprothiolane was higher in the washing process, and the case of fthalide was higher in the cooking process. The optimum washing process for the pesticides removal was five times and the cooking process was the most effective to use the new water after soaking the rice in water during 30 minutes.

• The Korean Journal of Food And Nutrition
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• v.24 no.4
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• pp.589-601
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• 2011

The purpose of this study was to investigate changes in the cooking process of $Pat-juk$(red beans porridge), $Jat-juk$(pine-nut porridge) and $Tarak-juk$(milk porridge) in cooking books published after Korean modern era, approximately from late 19th century to the present. We analyzed 11 historical cook books were analyzed. It is found that the amount of red beans used for $Pat-juk$ was the same or more than that of rice but never less than rice. Only one cook book suggested sugar as seasoning for final taste, but all the other cook books mentioned salt for final taste. $Hangukeumat$(1987) suggested the method for obtaining optimum color for $Pat-juk$. After smashing and passing through the cooked red beans, collecting the red bean water to boil first and then adding the passed through red beans to boil together, in which rice will be added the last to be boiled. For $Jat-juk$, the ratio of the amount of pine-nut and rice were varied among cook books that the amount of pine-nut can be more, same or less than rice. $Jat-juk$ can have salty or sweet, so sugar, honey or salt were used for final seasoning. Pine-nut and rice were cooked together or cooked successively depending on cook books. The changes in cooking procedures of $Tarak-juk$ were the portion of milk used and the method of preparing rice before making the porridge. Firstly, the portion of milk increased over time. $Tarak-juk$ can be also tasting both sweet or salty, so sugar or salt was used for final seasoning. Secondly, two method of preparing rice were found; one is that rice was ground after soaking in water and the other is that rice was ground and toasted before putting into the porridge. When the ground rice was toasted, the milk was added with water at the same time because the cooking time of the porridge with toasted rice was shortened so that the milk could be added earlier than the other method without the risk of sticking on the bottom of the pot. In further studies, the cooking procedures used in the previous period of the late 19th century should be examined. Also after restoring all the cooking methods suggested in cook books, the comparison of the sensorial and nutritional value needs to be carried out for applying or reinventing new recipe for food industry.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.8
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• pp.937-943
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• 2017

This study was performed to investigate the changes between free and bound forms of bioactive compounds in germinated adzuki bean. Adzuki bean was germinated at $25^{\circ}C$ for 6 days, and then free and bound forms of bioactive compounds were extracted. Total free polyphenol and flavonoid contents in of raw adzuki bean increased from 0.91 mg/g and 0.60 mg/g in before germination to 2.37 mg/g and 3.03 mg/g in at 6 days after germination, respectively. Bound polyphenol, flavonoid, and phenolic acid contents also increased with increasing germination periods, whereas bound polyphenol and flavonoid contents slightly reduced in at 2 days after germination. The total phenolic acid contents, including ferulic acid, veratric acid, hesperidin, salicylic acid, naringenin, and hesperidin, increased during germination, and germination process can convert compounds to phenolic acid via anabolism and catabolism. Total anthocyanin and anthocyanidin contents of adzuki bean decreased during germination due to hydration by water during soaking or enzyme activation of anthocyanase during germination. These results suggest that the germination process increased utilization of functional compounds such as phenolic compound and isoflavones in black soybean.

• Journal of the Korean Wood Science and Technology
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• v.10 no.3
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• pp.133-134
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• 1982

This experiment has been made to investigate the absorption of watersoluble zinc chloride by Pinus densiflora S. et Z. at different moisture content, under soaking process, to decide the optimum content condition for the maximum absorption of zinc chloride by the wood tested and to investigate the concentration of zinc chloride affecting each moisture content of wood. Material was cut in the Dept. of Forest, College of Agr. S.N.U. Suwon, Korea. Sample was divided into sap and heartwood group and cut $2{\times}2{\times}2\;cm$ in size, having exact three dimensions, using the part of D.B.H. The numbers of sample were 20 pieces for each moisture content condition for both sap and heartwood. Especially, the samples were protected from exposure to keep moisture content in green condition. The ranges of moisture content tested were as the table 3 and 4. The conclusions were as follows: 1. With 3% zinc chloride solution, the rate of absorption decreased with the time increased, if the air seasoned Korean red pine (Pinus densiflora S. et Z.) was treated in steeping process. Initial absorption for 30 minutes was more than 50% of total absorpon for 24 hours. 2. Rate of absorption was same under the green condition, while rate of absorption under the moisture content 7 to 30% varied. 3. Although it was not quite proportional change in the absorption with the difference of moisture content, the great change in the absorption occured by seasoning. With exception sap green condition, sapwood twice more permeable than the heartwood in the oven dried condition and it has been observed the nearly same amount of absorption at the moisture content of 7%, 10% and 15% respectively in heartwood. 4. It was better from water in wood from view-point of absorption of zinc chloride solution, but it was difficult practically to obtain the smallest moisture content, and then it was decided that values of allowable moisture content, on the basis of mean absorption, were 15% to 20% in the sapwood, and in the heartwood, 10% to 15%. The mean absorption for each moisture content in the sap and the heartwood were as following. 5. In general, the concentration of zinc chloride after steeping was nearly same between moisture content and sap and heartwood respectively.

• Journal of the Korean Geotechnical Society
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• v.17 no.6
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• pp.47-51
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• 2001

There are two strategies to cope with the troubles in landfill site after closure. The first method is active in a way that the wastes are dug up and the recyclable materials are reutilized, meanwhile the materials not recyclable are incinerated in order to minimize the volume of residues to be disposed of. The second method is rather passive and defensive in a way that the source of contamination, that is, buried wastes are not treated. Instead, the transport of leaking leachate and gases generated from the wastes are intercepted and controlled. In this study, as a passive way of the efficient leachate blocking process, applicabilities of geocrete and soluble sodium silicate as a substitute to control leachate leaking from landfill sidewall were investigated. In case of compression test, the strength of mixture I (Geocrete:Sodium silicate=1:3.9 v/v) and mixture II (Geocrete:Sodium silicate=1:2.5 v/v), even after 7 days' curing was higher than the minimum allowance to tolerate the loading(5 kg/$\textrm{cm}^2$). Soaking in the acid fur 4 days and 7 days respectively, the compressive strength of the specimens reduced seriously. The toxicity of geocrete is not detected through the bioassay test, once it was mixed with sodium silicate and the complex was formed. The hydraulic conductivity of the mixtures even after 7 days' curing was lower than the threshold limit $(1.0\times10_{-7}cm/s)$.

• The Korean Journal of Mycology
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• v.24 no.1 s.76
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• pp.81-88
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• 1996

Cereals were used as solid-substrate for the cultivation of Ganoderma lucidum. The hydration time with cold water appeared to be 10, 11 and 12 hours for Malt, Danyeob and Black soybeans respectively, and the water content was enough for mycelial growth in this condition. The hydration times required for sorghum, job's tears, barley, brown rice and wheat were 2.5, 4, 5, 10 and 12 hours respectively, but the final water content was much less than optimum water content (65%). Hot water reduced the hydration time of soybeans, and the water content reached to 65% within $120{\sim}150$mins. This condition showed the optimum for the mycelial growth. For the other cereals, it took about $17{\sim}120$ mins to reach the optimum water content (65%). From this result, hot water was better than cold water for the hydration of cereals. We attempted to develop a practically applicable process by combining the soaking and sterilization. This process was successful with soybean and about 1.1 times of water based on the weight of soybean appeared to be suitable. In all varieties of cereal, the water content of 65% appeared to be the best for the growth of the fungi and production of glucosamine related to the amount of mycelium. The mycelial growth rate in accordance with kinds of solid-state materials was in the order of barley > wheat > job's tears > sorghum > brown rice > soybean. The glucosamine content for determing the mycelial growth in solid material was in the order of wheat> barley > brown rice > job's tears > sorghum > soybean.