• The Korean Journal of Food And Nutrition
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• v.24 no.3
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• pp.434-441
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• 2011

In this study, certain quality characteristics of kimbugak samples prepared with 2 different puffing methods, microwave oven and frying, and containing different levels of sea tangle powder(0, 2, 4, and 6%), were examined according to mineral content, moisture content, color values, photographic images, hardness and sensory evaluations. The mineral contents of Porphyra yezoensis were: K, 2,612.400 mg; Ca, 116.970 mg; Na, 486.099 mg; Mg, 297.800 mg; Fe, 9.636 mg; Mn, 1.614 mg; and Cu, 0.973 mg. And those of the sea tangle powder were: K, 5,115.000 mg; Na, 1,848.931 mg; Ca, 763.030 mg; Mg, 525.700 mg; Fe, 15.125 mg; Zn, 4.639 mg; and Mn, 0.146 mg. Moisture content was not significantly different among the samples of kimbugak puffed by the microwave oven and frying. For the color of the kimbugak made with the microwave oven or frying, L values decreased as the level of sea tangle powder increased. Color a and b values were lowest in the control group. The color values(L, a, and b) of the kimbugak puffed by frying were higher than those made using the microwave oven. The hardness of the kimbugak samples puffed using the microwave oven were not significantly different according to levels of sea tangle powder, and in the kimbugak puffed by frying, the lowest hardness was in the sample with 6% sea tangle. In sensory evaluations, color and crispness were not significantly different among the samples. The flavor scores of the 4% and 6% samples puffed by frying were higher than those of the kimbugak samples puffed using the microwave oven. The overall acceptability of the kimbugak puffed by frying and containing 6% sea tangle powder was the highest. In conclusion, 4 and 6% sea tangle powder would be considered optimum amounts for kimbugak puffed by frying.

• The Journal of Korean Academy of Prosthodontics
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• v.58 no.4
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• pp.275-281
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• 2020

Purpose: Development of a latent antimicrobial soft liner is strongly needed to overcome a possible inflammation related with its dimensional degrade or surface roughness. Modified tissue conditioner (TC) containing chitosan-doped silver nanoparticles (ChSN) complexes were synthesized and assessed for their characterizations. Materials and methods: ChSN were preliminarily synthesized from silver nitrate (AgNO₃), sodium borohydride (NaBH₄) as a reducing agent and chitosan biopolymer as a capping agent. Ultraviolet-visible and Fourier transform infrared spectroscopy were conducted to confirm the stable reduction of nanoparticles with chitosan. Modified TC blended with ChSN by 0 (control), 1.0, 3.0 and 5.0 % mass fraction were mechanically tested by ultimate tensile strength (UTS), silver ion elution and color stability (n=7). Results: At 24 hour and 7 day storage periods, UTS values were not significant (P>.05) as compared with pristine TC (control) and silver ion was detected with the dose-dependent values of ChSN incorporated. Color stability of TC were influenced by ChSN add, with the higher doses, the significantly greater color changes (P<.05). Conclusion: A stable synthesized ChSN was acquired and modified TC loading ChSN was characterized as silver ion releasing without detrimental physical property. For its clinical application, antimicrobial test, color control and multifactor investigations are still required.

• Analytical Science and Technology
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• v.23 no.2
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• pp.216-223
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• 2010

In previous research, results on efficiency versus size and type of Ag particles showed similarity of detection efficiency comparing the particles of flake and spherical type with the gray particle on the market and in the case of nAg (rod, $0.9\;{\mu}m$) particle, relatively good results was given in the various evaluation methods for detection efficiency of latent fingerprint. However, oxidation was occurred when nAg particles laying on nature condition for a month and due to water absorption, detection efficiency was decreased. Therefore, with need to prevent oxidation and water absorption, more research is necessary. In this research, surface modification on nAg particles using silicon oil was conducted in various methods for complementing weakness of oxidation and water absorption. Then detection efficiency of nAg particles and surface modified nAg particles was evaluated by the number of feature points on the surface of non-porous materials (glass, plastic etc.) and degree of particle adhesion with ridges and contrast of detected fingerprint. Improvement of preventing oxidation and water absorbtion was given by surface modification using silicon oil (DC200, 0.5%) on the surface of non-porous materials.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.7
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• pp.736-747
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• 2011

This study investigates the current status and dyeing properties of various natural indigo powder dyes in the domestic market. Products from India, China, Europe are sold in the market and only a few manufacturers provide recommendation for the method of dyeing and information on the additives. Through the market research and the preliminary investigation on 21 products, 11 were selected for the dyeing experiment which include 3 Indian, 3 Chinese, 2 German, and 1 Pakistani origin indigo reduced powders, and 2 Indian origin dried indigo leaf powder. The two dyeing methods used were the precipitation method and the fresh juice method, both at $10^{\circ}C$, $25^{\circ}C$, and $60^{\circ}C$. Color difference, K/S value, and colorfastness of dyed cotton fabrics were examined. Indian reduced indigo powder showed the highest K/S value, deep dyeing, and the best color fastness. Chinese reduced indigo powder resulted in a more greenish and bluish color. Powders of dried indigo leaves were easy to use but resulted in a pale color due to low dye uptake.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.53.2-53.2
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• 2009

몰리브덴(Mo)은 우수한 전기전도도와 고온 안정성으로 인해 전자부품의 전극으로 널리 사용되고, 미래 에너지인 태양전지 분야에서 CIS계 화합물박막태양전지의 후면전극으로 이용되고 있는 재료로서 현재 증착 방법으로는 D.C. sputtering이 가장 널리 이용되고 있다. 또한 $MoO_3$ 분말이 Mo 분말로 수소 환원되는 과정은 $MoO_3+H_2{\rightarrow}MoO_2+H_2O$ 와 $MoO_2+2H_2{\rightarrow}Mo+2H_2O$의 2단계를 통해서 수행되며 이중 첫 번째 단계에서 $MoO_3(OH)_2$라는 기상을 통해 지배적으로 일어난다고 알려져 있고 이를 화학증기수송(Chemical vapor transport : CVT)이라고 한다. 본 연구에서는 $MoO_3$분말의 수소 환원 과정 중에 발생하는 기상인 $MoO_3(OH)_2$을 이용하여 몰리브덴 옥사이드 박막을 증착하고 이를 다시 수소분위기에서 수소 환원하는 증착 방법을 통해 균일하고 부착성이 우수한 Mo 박막을 제조하고자 하였다. 기판으로 사용된 Glass를 $MoO_3$ 분말 위에 홀더를 이용하여 $MoO_2$ 박막을 증착하고 이를 다시 수소분위기에서의 수소 환원을 통해 Mo 박막을 성공적으로 제조하였다. 제조된 Mo박막의 결정구조 및 미세조직을 XRD 와 SEM을 통해 분석하였다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.7
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• pp.993-998
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• 2011

Citrus peel powder was used to substitute 2%, 4% and 6% rice flour for making sulgidduk. Proximate composition, sensory characteristics, and principle components of sulgidduk containing citrus peel were analyzed and compared with those of sulgidduk. Protein, fat, carbohydrate, ash, color b-value (yellowness index), springiness, and adhesiveness of sulgidduk all significantly increased, whereas color L- and a-values, hardness, cohesiveness, and chewiness of sulgidduk decreased with the addition of citrus peel powder. No significant differences were observed regarding the contents of moisture and carbohydrates, or fracturability in any of the samples. Substitution of rice flour with citrus peel powder showed acceptable sourness and bitterness sensory scores, which were comparable to sulgidduk. Principle components analysis revealed total variation of 94% in the main structured information: PC1 and PC2 showed 79.31% and 14.69% variation. CP-B (citrus peel powder 4%) and CP-C (citrus peel powder 6%) associated the strongest with PC1 and sulgidduk without citrus peel powder associated with PC2. Attributes associated strongly with PC1 were color, bitterness, adhesiveness, and sourness. Therefore, sulgidduk containing CP-B can be developed based on its favorable quality characteristics and sensory evaluation.

• Journal of Life Science
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• v.30 no.12
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• pp.1042-1053
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• 2020

The physicochemical properties, antioxidant activity, color value, sensory evaluation, and sinigrin content of chicken breast jerky supplemented with Dolsan leaf mustard powder (DLMP) were evaluated over a period of 120 days. The control groups contained no DLMP, and the product groups contained 0.04 g (S-1, S-3) and 0.3 g (S-2, S-4) of DLMP. These samples were stored at 25℃ and 60℃ and then compared. The pH changes decreased at 25℃ and 60℃ over the storage period, with S-1 maintaining the highest pH value over the course of the experiment. The acid and peroxide values increased at room temperature and 60℃ but were better controlled in the DLMP-containing groups. Overall, the antioxidant activity of these products decreased during storage; the most marked reduction was observed in the control group, and the greatest activity was retained in S-2 and S-4. Hardness and gumminess were higher in the S-2 and S-4 groups and thus correlated with increased DLMP concentration. Sinigrin content also increased with increasing DLMP concentration. Product color remained similar at days 0 and 120 but underwent daily fluctuations over the course of the 120-day storage period. Sensory evaluation scores for color, flavor, taste, texture, and overall acceptability were highest for the S-2 and S-4 groups stored at 25℃. This suggests that higher concentrations of DLMP were more effective at retaining good quality characteristics for fried chicken breast jerky. This was facilitated by its suppression, which decreased changes in textural and color properties while increasing the antioxidant activity of these products.

• Applied Biological Chemistry
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• v.30 no.3
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• pp.234-241
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• 1987

Conditions necessary for optimal plastein productivity from sardine protein hydrolysate using papain and pepsin were established. Sardine protein concentrate was hydrolyzed with pepsin yielding an approximate degree of hydrolysis of 77.2%. Enzyme induced plastein was optimized at: pH 6 for papain and pH 4 for pepsin; substrate concentrate, 50%(w/v) for papain and 40%(w/v) for pepsin; time of incubation, 24hr; enzyme/substrate ratio, 1 : 100(w/w). Plastein yields of 49.5% and 45.3% were found for papain and pepsin, respectively, when 10% trichloroacetic acid (TCA) was used as the precipitating agent. However, when plastein was precipitated by 50% ethanol, the yield was found to be 43.6% and 41.0% for papain and pepsin, respectively. Ethanol-precipitated plastein did not contain lipid and contained approximately 1.3% ash and 91.0% protein. In comparison, the TCA-precipitated plastein contained 74.2% protein, 0.5% lipid and 15.3% ash.

• Resources Recycling
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• v.15 no.4 s.72
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• pp.19-26
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• 2006

The preparation of Ag nano-powder from aqueous silver nitrate solution, which would be available for the recycling of silver bearing wastes, was investigated by a reductive precipitation reaction using hydrazine hydrate as a reducing agent. Silver solution was prepared by dissolving silver nitrate with distilled water, and then the dispersant, Tamol NN8906 or Tween 20, was also mixed to avoid the agglomeration of particles during the reductive reaction followed by the addition of hydrazine hydrate to prepare Ag nano-particles. Ag particles obtained from the reduction reaction from silver solution were characterized using the particle size analyzer and TEM to determine the particle size distribution and morphology. It was found that about 100% excess of hydrazine hydrate was required to reduce completely silver ions in the solution. Ag powders with very narrow distribution could be obtained when Tamol NN8906 was used as the dispersant. In case of Tween 20, the particle size distribution showed typically the bimodal or multimodal distribution and the morphology of Ag particles was found to be irregular shape in both cases.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.6
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• pp.107-112
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• 2018

Shielding effectiveness (SE) improvement with EMI shield layers fabricated by conformal spray coating system was studied. Silver or Nickel powder filled acrylic resin were sprayed on the samples. We compared the performance with the viscosity of 400 cPs and 100 cPs cases. The thickness range of the coating layer was 20 to 50 um for the silver, 60 to 120 um for the nickel. The shielding effectiveness was measured by ASTM D4935 using coaxial type TEM-cell. The silver-filled resin showed much better performance than that of the nickel-filled resin. The shielding effectiveness increased almost proportional to the thickness of the coating layers until being saturated around 63 dB for the silver-layer or around 34 dB for the nickel-layer. The best performance measured in this study was the shielding effectiveness of 63 dB with $35{\mu}m-thick$ of silver-layer.