• Journal of the Microelectronics and Packaging Society
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• v.24 no.3
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• pp.57-62
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• 2017

In the process for preparing Ag-coated Cu flakes by electroless silver plating using hydroquinone reducing agent, Ag coating qualities were compared by changing various process parameters such as type of pretreatment solution, plating temperature, pH of plating solution, type and injection rate of plating solution, and pulp density. Effective pretreatment solution for removing the oxide layer on a Cu flake was preferentially suggested. The conditions of low plating temperature, pH value of 4.34, slow injection rate of Ag plating solution, elimination of deionized water in the Ag plating solution, and high pulp density significantly suppressed the formation of separated tiny Ag particles, and thus the surface coverage of Ag coating on Cu flakes was enhanced.

• Textile Coloration and Finishing
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• v.29 no.3
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• pp.115-121
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• 2017

Demands for nylon suede as an artificial leather are increasing due to its functionality and aesthetics. To achieve high value added nylon suede based on green technology, this study was carried out in order to obtain useful data for the nylon suede fabrics with eco-friendly dyeing process by a pad-steam method instead of a dip dyeing process using sulphur black dye to reduce the industrial waste of water. The dyeability of the nylon suede was investigated according to reducing temperatures, dye concentrations, and reducing agent's concentrations. Throughout the results of the CIE $L^*a^*b^*$ and Munsell values, the optimized dyeing conditions of the nylon suede using sulphur black dye are $70^{\circ}C$ of dyeing temperature, 30% o.w.f. of dye concentration, and $9g/{\ell}$ of reduction agent concentration, respectively. Furthermore washing colorfastness, light colorfastness and perspiration colorfastness were achieved in the range of 4-5 grades.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.2
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• pp.41-56
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• 2012

Landscape space can and should play as a multi-functional agent : healing contaminated soil, reducing natural hazards, supporting living things, making comfortable environment for human, and appealing to human aesthetics, etc. This article aims to show the possibility and role of landscape space as such agent. In landscape design for National Marine Biology Resource Institute, distributed rain water treatment system and rain gardens are introduced to replace a mono-functioning large detention pond which was suggested by disaster impact assesment. Phytoremediation and vegetation filtering system with muti-cell wetlands are also adapted to heal the contaminated soil. This kind of landscape as a 'living machine' which can play as an operational control utility of multi-environment and thus can be combined effectively into green infrastructure is important for post-industrial city, especially in an era of climate change.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.11a
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• pp.29-36
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• 2002

High fluid concrete unlike OPC concrete is made with various material, and the phase of fresh concrete is considerably different. In order to understand fluidity phase and mix properties of high fluid concrete, concrete is required to access as suspension structure which consists of aggregate and paste. The focus of this paper is to analyze the test results and quantify the effect of mix proportions of molar and fineness modulus of ,and on the properties of fresh mortar. The effect of water-binder ratio, sand-binder ration, content; of ggbs (by mass of total cementitious materials), and various contents of water reducing agent on the yield stress and plastic viscosity of the mix is studied. Based on the experimental results, the following conclusion; can be drawn: (1) The mixing time needed (or high fluid mortar was approximately two times more than that of ordinary portland mortar. (2) The fluidity phase of mortar could be explained by yield stress of mix and the fluidity of mortar. (3) As the content of ggbs increased, yield stress of mortar was decreased and plastic viscosity of it was increased. (4) For the high fluid mortar, it was appeared that sand-binder ratio should be below 1.5.

• Journal of the Korea Concrete Institute
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• v.12 no.5
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• pp.111-120
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• 2000

In case of constructing concrete structure under water, generally concrete mixed with antiwashout admixture, high range water reducer, or AE-water reducing agent etc has been manufactured to ensure the quality of antiwashout underwater concrete because of being difficulty in ascertaining construction situation by the naked eye. The properties of high quality antiwashout underwater concrete that were aimed at affluent fluidity, workability and the compressive strength of 450 kgf/$\textrm{cm}^2$ at 28 ages using two types of blended cements are following as;(1) Setting time of antiwashout underwater concretes using blended cements was more greatly delayed than that of control concrete, however, was satisfied with criteria value of "Quality standard specification of antiwashout admixture for concrete".(2) As a test results of slump flow, efflux time and box elevation of head, it was found that workability of high quality antiwashout underwater concrete was improved. (3) Heat evolution amount of OPC was 1.5 times as high as that of two types of bended cements in 72 hours. (4) Suspended solids of antiwashout underwater concrete using blended cements was more than that of control concrete, also compressive strength of high quality antiwashout underwater concrete was very low in early age, but was better than that of control concrete as to increasing ages.

• YAKHAK HOEJI
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• v.51 no.6
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• pp.500-507
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• 2007

To investigate the possibility of development as a whitening agent using bamboo extracts (Phyllostachys nigra var. henonis), we measured DPPH assay, NBT/XO assay, intracellular ROS scavenging assay, tyrosinase assay and MSH-induced melanin production in B-16 cells. Bamboo extracts had dose-dependently anti-oxidant activity in DPPH, NBT/XO and intracellular ROS assay. Bamboo extracts appear to inhibit xanthine oxidase directly. Bamboo extracts inhibited not only purified tyrosinase activity but also inhibited tyrosinase activity and melanin production in B16 melanoma cells stimulated by $1{\mu}M\;{\alpha}$-MSH. Anti-oxidant activity and cytotoxicity of ethyl acetate fraction was more potent than those of water fraction, whereas whitening effect of water fraction was stronger than ethyl acetate fraction. Therefore, these results suggest that water fraction of bamboo extracts may be useful for the development as whitening agents reducing cytotoxicity.

• Journal of the Korea Institute of Building Construction
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• v.7 no.4
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• pp.117-124
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• 2007

Focused on the material-related aspect for enhancing the durability of concrete, the present study analyzed the effect of glycol ether admixture, which is a chemical admixture that can compact the structure of concrete by entraining air inside the concrete, on the basic physical properties and durability characteristic of the concrete. In analyzing the results of experiment, we examined the basic physical properties and durability characteristic of concrete according to addition rate based on OPC and selected the optimal addition rate. In addition, with the optimal addition rate, we added glycol ether admixture to concrete, which contained fly ash used as binder and high-performance water reducing agent for reducing the unit quantity, and examined changes in the characteristics of the concrete. According to the result, the optimal addition rate of glycol ether admixture was 3% of the unit quantity of cement, and the addition of binder and chemical admixture did not have a significant effect on unhardened concrete but reduced the air content. In addition, concrete showed resistance performance of around 30% to carbonation and around 40% to drying shrinkage. In addition, as for resistance to freezing and thawing, the relative dynamic modulus of elasticity was over around 85% through atmospheric curing. These performances prove the effect.

• Culinary science and hospitality research
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• v.23 no.8
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• pp.11-16
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• 2017

In this study, two kinds of mealworm seasoning pastes (naturally fermented or inoculation of Bacillus subtilis) were prepared by applying fermentation method of chungkukjang. The samples were labeled into soybean control (SC; no fermentation), mealworm control (MC; no fermentation), mealworm natural fermentation (MR) and mealworm inoculated fermentation of Bacillus (MB). Water content, color, pH, titratable acidity, salinity, amino acid nitrogen, reducing sugar and preference test were examined on the pastes. Moisture contents were 46.9 with soybean control (MC) and 54.5~73.3 with mealworm pastes. The L-value was not significantly different between the samples. In the case of the a-value and the b-value, SC showed the highest value whereas mealworm pastes showed lower values than SC. pH and salinity were higher in mealworm pastes. Amino nitrogen and reducing sugar showed the highest values of MR 326,67 and 63.33 mg%, respectively. In the preference test, the appearance and flavor were the highest values with SC, but texture, taste and overall acceptability were with MR, Therefore, soybean fermentation method with Bacillus species could be applied to use protein of mealworm and possibly edible insects as well.

• Journal of the Korea Fashion and Costume Design Association
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• v.16 no.1
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• pp.117-123
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• 2014

This paper examined dyeing using sulfur dye with nylon and the characteristics of high gauge knitting for generating high functionality including light weight, wind resistance and elasticity using fine nylon threads. Yarn tension, stitch field and knitting speed of high and fine gauge knitting were measured. The influence of reducing agents on sulfur dye, optimum dyeing conditions and fastness features in nylon dyeing were analyzed. The analysis results are presented below. When nylon (Hyoseong, 40d/34f) and spandex (Hyoseong, 20d) for use as hosiery yarn were used to knit high gauge and flat weave, 44 gauge, the effective knitting conditions were a stitch field over 8.2cm in 1 course length, yarn tension of less than 5g and knitting speed below 18rpm. Nylon dyeing using sulfur dye showed effective results when a rongalite reducing agent was used at more than 10% o.w.f. and dyeing was maintained at $98^{\circ}C$ for 30 minutes. For dyeing nylon and spandex composite using sulfur dye, color fastness in washing, water, daylight and friction were higher than Class 4 or 5, which indicated a superior property. The analysis results verified that the existing problems in nylon dyeing could be solved by using sulfur dyes that don't use heavy metals due to superior fastness and therefore quality, high gauge nylon knit products could be produced.

• Applied Biological Chemistry
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• v.38 no.6
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• pp.563-569
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• 1995

Effect of protease and 2-mercaptoethanol treatment on the texture of cooked rice was investigated. Hardness, chewiness and gumminess of cooked rice were decreased by reducing the disulfide bonds of protein using 2-mercaptoethanol. Protease-treated rice grains, when cooked, showed more favorable results in stickiness measured by Instron, hardness measured by rheometer and sensory acceptability of cooked rice. Water content and volume expansion of cooked rice were increased by protease or 2-mercaptoethanol treatment. This results suggested that the textural characteristics of cooked rice may be influenced by surrounding or closely associated protein.