• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.12
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• pp.1662-1671
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• 2007

The change in physical properties of polypropylene nonwoven fabrics used as top sheet for disposable sanitary goods was carried out using chitosan that is a type of natural polymer and has excellent human affinity by varying the molecular weight and concentration of chitosan. Low molecular weight(LMW) chitosan treated fabrics were found to be evenly coated on fabrics and had better dyeability by apparent dye uptake and its deodorization rate increased over the time. On the other hand, high molecular weight(HMW) chitosan treated fabrics showed higher add-on ratio and its dynamic water absorption rate and represented an increase in water transport rate. With chitosan treatment, its air permeability was improved. Regardless of the type of bacteria and chitosan concentration, its antibacterial activity was excellent in the case of the HMW chitosan treatment. In this regard, chitosan treatments by using a relatively high molecular weight was found as an effective way in the functional improvement of moisture properties and antibacterial activity including their most important performance in sanitary nonwoven fabrics.

• Journal of agriculture & life science
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• v.52 no.6
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• pp.81-88
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• 2018

This study analyzed the characteristics of 6 recyclable bulking agents which can replace sawdust and rice hulls that are commonly used in livestock manure composting. The content of all the hazardous chemicals found in the bulking agents used in this experiment was between 0.0 and 34.1 ppm, which was noticeably lesser than the maximum content levels of hazardous substances 5.0~900.0 ppm prescribed by the Rural Development Administration(RDA), which means that the bulking agents would be able to replace sawdusts and rice husks. The water content of the bulking agents ranged from a minimum of 12.4% to a maximum of 16.6% in the original state, which was much less than 60%, the optimal moisture content. These results indicate that they would be able to function fully as bulking agents. Their water absorption rate was in the range of minimum 31.9% ~ maximum 600.0%, which showed huge differences among the types of bulking agents. The most appropriate bulking agent in terms of water absorption rate was wood pellets. It was the highest in the wood briquette manufactured by A, which was followed by C and B in the order. The shear strength of the 5 types of bulking agents in the original state was 271.7 N on an average, the highest figure of all, except for the oak briquette whose shear strength could not be measured and the wood pellets in the absorption state. The shear strength in the dry and absorption states then followed, and were 78.0 N and 27.7 N on an average, respectively. The wood briquette of A recorded considerably lower shear strength than that of B and C. Overall, shear strength tended to increase according to lower water absorption rates. Since pine wood chips and oak cuts have relatively greater shear strength even in the absorbing state than the other materials, they will be able to endure some power in the case of stirring with pig droppings.

• Applied Biological Chemistry
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• v.26 no.1
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• pp.1-7
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• 1983

The hydration of two japonica(Akibare and Milyang 15) and four indica(Milyang 30, Suweon 287, Suweon 294 and Iri 342) rice varieties was investigated in terms of mathematical rate equation. The hydration rate at temperatures of $4{\sim}32^{\circ}C$ was examined by a weighing method. The absorption of water was directly proportiponal to the square root of the hydration time(t) and was described by the diffusion equation: $1-\bar{M}=(2/\sqrt{\pi})(S/V)\;\sqrt{Dt},\;where\;\bar{M}$ is dimensionless moisture ratio, S/V is the surface-to-volume ratio and D is diffusion coefficient. The average D value was given by the Arrhenius relation: $D=D_0\;\exp(-E_a/TR)$. The activation energy was $4{\sim}5kcal/mole$. The rice samples could be classified into three groups based on hydration kinetics: Milyang 30-Suweon 287; Akibare-Milyang 15; and Suweon 294-Iri 342.

• Applied Biological Chemistry
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• v.33 no.1
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• pp.14-17
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• 1990

Seven varieties of soybeans(Paldal, Danyeob, Jangbaek, Baegun, Jangyeob and 2 cultivars of Local 1 and Local 2) were investigated to compare the sorption characteristics during storage of various relative humidities. The sorption isotherm curve determined at RH range of $33{\sim}92\;%$ and $4^{\circ}C$ and $25^{\circ}C$ showed that moisture contents of soybeans was higher at $4^{\circ}C$ than those values at $25^{\circ}C$ for overall water activities of 0.33{\sim}0.92$. The Paldal was the highest moisture content at $4^{\circ}C$ while that value of Baegun was the highest at $25^{\circ}C$. The change in moisture content with storage time was expressed by log(dw/dt)=b log(t)+log a and the value of (dw/dt)${\times}10^3$ was decreased logarithmically. The Paldal was comparatively the highest initial absorption rate and the value of -b in seven varieties decreased as the relative humidity increased from 33 % to 92 %.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.4
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• pp.439-446
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• 2007

We carried out this experiment on the purpose to investigate the quality properties of aseptic-packaged cooked rice by cultivars in 2006. Brown rice was milled for white rice to 89.6% weight of it. Based on cluster analysis of acceptance of sensory evaluation, eleven rice cultivars of 29 cultivars had superior palatability. Whiteness(r=0.42, p<5%), lightness(r=0.39, p<5%), Toyo value(r=0.35, p<10%), and moisture content(r=0.33, p<10%) of milled rice were correlated positively with acceptability. Protein content(r=-0.40, p<5%), expansion rate(r=-0.68, p<1%) and water absorption rate(r=-0.42, p<5%) of milled rice, and yellowness(r=-0.45, p<5%) of aseptic-packaged cooked rice were negatively correlated. In sensory evaluation, correlation coefficients of taste and texture with acceptability were higher than those of appearance and flavor. During storage, hardness and cohesiveness of aseptic-packaged cooked rice before reheating were increased and decreased, but those after reheating had no difference based on storage period and cultivar. On the contrary, whiteness of reheated aseptic-packaged cooked rice with no distinct differences before reheating was decreased during storage. There were no significant differences of texture property, color characteristics and moisture contents by cultivar during storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.6
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• pp.617-624
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• 1990

Proper processing condition of Yukwa(oil popped rice snack) for mass production and pop-ping mechanism of it were tested with Shinsun (waxy, Japonica type rice) which was excellent for Yukwa making. Optimum steaming time of dough was 15 min among 4 to 60 min and reasonable moisture content of the dough before steaming was 4895 among 48 to 53% which had good and fine texture. Acceptable stirring time of steamed dough was not significantly different among 1 to 4 min, but no stirring with much larger volume was shown very poor and too soft in texture. At the simplification test of milling method, wet milling was better then dry milling in expansion rate and high temperature treatment of dough at 6$0^{\circ}C$ gave negative effect on their quality. Extending high temperature treatment of dough, reducing sugars in the dough increased and it might be caused of starch degradation. In addition of some other protein sources to dough, Yukwa quality were in proportion to the protein content of the beans. At the long term storage of the Yukwa base, moisture absorption was different depending upon RH of atmosphere and the quality of Yukwa was inferior by storage time. By addition of some alcoholic beverage, such as Makkoli, Soju and Chungju, expansion rate and their texture were somewhat improved by increasing addition amount of them from 15% to. 30％ on dough (w/w).

• Conservation Science in Museum
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• v.17
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• pp.101-116
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• 2016

Ceramic cultural artifacts restored with gypsum-based materials are prone to decay over time due to gypsum's natural absorption and release of atmospheric moisture, often leading to distortion and peeling of painted layers. This study proposes a new restoration material which utilizes extra hard stone, significantly superior in strength to regular gypsum. In order to enhance its physical properties and make it suitable for restoration of ceramics, extra hard stone is mixed with metakaolin. This mixture far surpasses regular gypsum in compressive strength(119MPa vs. 26MPa) while also maintaining a much lower wear rate(0.88% vs. 2.53%). Furthermore, the water absorption rate(2.9%) of the mixed material is over five times lower than that of regular gypsum(17.2%). When examined using a SEM(Scanning Electron Microscope), this mixture also proved superior to extra hard stone in terms of hardened density. The addition of metakaolin increases the mixture's strength and water resistance over that of extra hard stone and also improves its surface density, making it ideal for the restoration of ceramics. It has already been used to repair ceramic objects in the Museum's collection: Clay basin(sinan 18892), Buncheong ware bottle with incised peony design(jubsu 2034), Buncheong ware bowl with chrysanthemum(jubsu 1730). Results thus far have shown the mixture to be easy to inject and layer as well as harden into an even surface, which allows for smooth application of paint for color matching.

• Korean journal of food and cookery science
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• v.32 no.1
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• pp.50-57
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• 2016

In this study, kim (dried laver) bugak ("KB"), Aster yomena bugak ("SB"), and namul (vegetables)-kim bugak (combination of Aster yomena and kim) ("NB") were prepared and their quality characteristics were investigated. NB was made by slicing Aster yomena, seasoning it with perilla seeds, attaching it to kim and applying glutinous rice paste, followed by freeze-drying. SB had a higher oil absorption rate than KB, reflecting the high oil absorption rate of namul (here, Aster yomena). DPPH radical scavenging activity was highest for SB; whereas, NB had higher DPPH radical scavenging activity than KB, indicative of the higher antioxidant capacity of namul, as compared to kim. With longer storage period, moisture content tended to be increased, while maximum load, yield stress and hardness tended to be decreased. Overall preference was in the order of NB>KB>SB, without statistical significance. Acid value and peroxide value of NB, stored at $25^{\circ}C$ for 40 days, tended to be increased gradually but did not meet the criteria for rancidity. Therefore, NB could be stored at $<25^{\circ}C$ for > 40 days. Furthermore, it would be possible to make functional bugak using a variety of namul, as well as Aster yomena.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.10
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• pp.1664-1672
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• 2013

Solar salt is manufactured naturally, and therefore, it contains insoluble substances such as sandy compounds. This study is performed in order to effectively produce clean sea salt by removing the impurities in sea salt through filtration and evaporation in a vacuum condition. Brine was concentrated and crystallized at $90^{\circ}C$ by a rotary vacuum evaporator, which was then recovered as salt crystals by filtration, and then the salt was dehydrated. Manufacturing yields were determined by the amount of water evaporation. Brine was concentrated to 40%, 50% and 60% of the initial volume of brine and manufactured salt were designated as 40S, 50S and 60S, respectively. The salt produced by this process is called ESBS (evaporated salt with brine from salt-farm). The yield of 40S, 50S and 60S were 7.22%, 10.79% and 15.06%, respectively. The NaCl concentration of 40S and 50S were 90.38% and 91.16%, respectively. From a sensory evaluation analysis, the most tasty salt was 40S and the bitter salt was 60S. The average contents of sand compound and insoluble substances in ESBS were 0.001~0.012% and 0.067~0.12%, respectively. The mineral compositions, such as Na, Mg, K, and Ca of 40S and 50S were similar with those of the natural solar salt. In solubility tests, the solubility (g of salt/100 mL $H_2O$/sec) of 40S, 50S, and 60S was 0.69, 0.70, and 0.69, respectively. On the other hand, the solubility of natural solar salt was 0.47. By comparing the water reabsorption rate analysis results, water reabsorption rate of 40S and 50S was about 3 to 5 times lower than that of the solar salt. In the aspects of physical and chemical properties, such as minerals, impurities, solubility and moisture re-absorption rate, salts developed in this study are judged to be better than that of the general solar salt.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.5
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• pp.291-297
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• 2005

This study evaluated the quality of commercial extruded pellet (EP) diet of five companies (A, B, C, D and E) for olive flounder Paralichtys olivaceus by biochemical analyses, physical properties and growth performance. The proximate analyses of five EP diets showed $3.2-10.0\%$ of moisture, $49.3-55.5\%$ of crude protein, $4.6-14.7\%$ of crude lipid, $7.0-13.8\%$ of crude ash, $0.7-10.5\%$ of crude fiber, $10.0-27.3\%$ of itrogen free extract (NFE), 304.3-395.4kcal/100g of digestible energy (DE) and 6.1-7.1 of calorie/protein ratio (C/P). Peroxide value (POV) was highest in diet D (47.4 meq/kg) as compared to other diets which in the range of 4.0-11.7 meq/kg. Total amino acid contents were ranged from 46.54 to $55.46\%$ with the highest content in diet B and the lowest content in diet C. Essential amino acid of diet C was lowest $(7.43\%)$ as compared to other diets which in the range of $19.43-20.30\%$. Saturated fatty acid was higher in diet A $(37.65\%)$ followed by diet B $(36.32\%)$, diet E$(34.39\%)$, diet C$(30.95\%)$ and diet D$(30.10\%)$. EPA+DHA were highest in diet E$(30.78\%)$ and lowest in diet C$(15.48\%)$. The floating rate after 6 hours on the sea water was highest in diet C$(100\%)$ followed by diet B$(40\%)$ and A$(10\%)$. However, diets D and E were completely settled down after 1 and 2 hours, respectively. The range of relative expansion rate was $27.2-49.3\%$ for all diets and all reached the peak at 2-3 hours. The water absorption rate of diets C and D was lowest, and diet E was highest at 1 hour after deposition of sea water. Growth rate was higher in diet B$(22.3\%)$ and E$(21.3\%)$. Feed efficiency was higher in diet A$(109.7\%)$ and E$(105.3\%)$ and was significantly lowest in diet D$(80.7\%)$. The protein efficiency ratio was highest in diet E (2.72) and lowest in diet D (1.76). These results suggest that there is a necessity for improvement of nutrients balance and feed physical properties to fulfill the nutrient requirements and digestive characteristics of fishes in commercial EP diets.