• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.3
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• pp.427-433
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• 2013

This study was designed to examine changes in the physicochemical properties of extruded corn fibers with different amounts of feed moisture (30, 40, and 50%). The screw speed and die temperature were fixed to 200 rpm and $140^{\circ}C$, respectively. The crude ash, fat, and protein in corn fiber decreased from the extrusion process. The insoluble dietary fiber in corn fibers decreased, while soluble dietary fiber increased at a feed moisture of 30%. The specific length of the extruded corn fiber increased while the specific mechanical energy input, density, breaking strength, and elastic modulus decreased. The water absorption index (WAI) and reducing sugar content of the corn fibers did not significantly change, but the water soluble index (WSI) decreased as the feed moisture content of the corn fiber increased. On the other hand, the WAI of de-starched corn fiber decreased while WSI and reducing sugars increased as the feed moisture content of the corn fiber increased.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.258-260
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• 2001

최근 연안역의 급속한 공업화와 산업화 및 도시화에 의한 인구 집중은 연안 해역의 부영양화 및 번번한 적조를 일으키는 주요요인으로 고려되어 왔는데, 하구역을 통해 해역으로 유입되어지는 다양한 물질들의 농도분포는 물리적인 혼합에 의한 보전적인 혼합 특징을 보이거나 생지화학적인 여러 복잡한 요인들에 의해서 결정된다. 특히, 중금속원소들은 지속성이 매우 커서 일단 자연환경 내로 투기되면 강우 및 대기를 통해 바다로 유입되고 해역 내에서 이들 원소들은 물리화학적인 여러 가지 과정에 의해서 해저퇴적물로 침강희적, 외해수와 혼합ㆍ확산되어지거나 혹은 먹이사슬을 통해 생물 농축(Bioaccumulation)되어 결국 인간에게 돌아온다 (Aston, 1978; Lee et al., 1981). (중략)

• Journal of Korean Society of Environmental Engineers
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• v.22 no.5
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• pp.819-825
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• 2000

The physico-chemical characteristics and the combustion activities of a waste automotive catalyst were carried out in this study. The physico-chemical characteristics of waste automotive catalyst was examined by EA(Elemental analysis), ICP-AES (Inductively coupled plasma-atomic emission spectrophotometer), and XRD(X-ray diffraction) analysis. Carbon deposit amount was higher in front brick than rear brick of catalyst, and increased with mileage. The content of Pt. Pd and Rh in waste automotive catalyst was different from the car manufacturing company. The combustion activities of waste automotive catalyst were investigated for acetaldehyde as a model VOC in a fixed bed reactor at atmospheric pressure. The catalytic activity of rear brick for acetaldehyde combustion was better than front brick of waste automotive catalyst. The catalytic activity of waste automotive catalyst for acetaldehyde combustion decreased with mileage. The linear relationship between catalytic activity and mileage was negative and has a very excellent correlation. Finally, the waste automotive catalyst has a good catalytic activity for acetaldehyde combustion. and can be used to control of small emission source.

• Conservation Science in Museum
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• v.25
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• pp.63-84
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• 2021

In order to investigate the diverse physicochemical changes that occurred in traditional Korean pottery during its production, including before and after firing, this study produced six replicas of a celadon maebyeong inlaid with cloud-and-crane designs, respectively corresponding to the process of shaping, carving, inlaying designs, first firing, glazing and second firing, respectively. It then conducted a scientific study of these six replicas and analyzed their images through high-resolution three-dimensional transmission imaging. The materials used for the replicas show different mineral phases and even colors depending on the components of each material. For example, black inlay with a high content of iron oxide (Fe₂O₃) shows dark colors and white inlay with a high alumina (Al₂O₃) content appears white. Physicochemical properties such as chromaticity and magnetic susceptibility and major components of the replicas were confirmed by the differences in the density in the computed tomography (CT) images. The characteristics of fired products such as fine structure, absorption ratio, apparent porosity, and other characteristics of the major mineral components were identified by the presence of pores and the formation of cracks inside the replicas in the image analysis.

• Journal of Korea Water Resources Association
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• v.35 no.5
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• pp.475-484
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• 2002

A series of settling tests and physico-chemical property tests on Saemankeum fine-cohesive sediments has been conducted in order to investigate the correlation between settling properties and their physico-chemical properties which are represented as grain size distribution, mineralogical composition, and percentage of organic contents. Experimental results of physico-chemical property tests show that Saemankeum sediments are relatively large in average grain size(52${\mu}{\textrm}{m}$), and contain very small organic materials(2%), and are dominantly composed of Quarts in mineralogical aspect which has relatively low cohesion. Thus, Saemankeum sediments might be specified as the sediments whose settling properties are more influenced by the gravity than the cohesion. This characteristics of Saemankeum sediments are found to lead to relatively small settling velocity in flocculated settling region in which increasing cohesion results in increasing settling velocity, while relatively large settling velocity in hindered settling region in which settling velocity decreases with increasing cohesion.

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.4
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• pp.112-120
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• 2004

In this study, the physico chemical characteristic of MSW and sludge in west area of Kangwondo was investigated for database, managing the waste and waste treatment facility. The sampling sites were selected as 6 different MSW generation area and 2 sludge generation area. it is necessary to measure the characteristics of MSW to build the data-base. The year of 2000, 197.4ton/day of MSW which was generated in this area. This MSW was composed of 26.6% food wastes, 24.2% of papers, 22.8% of plastics & vinyls, 9.6% of textiles, 3.80% of wood, 2.8% of rubbers & leathers and others, respectively. Most of MSW are composed of food, paper and plastic waste and combustible waste is more than 89%. The generation of papers and vinyls are almost same for different seasons For 3-components of MSW, moisture is 40.2%, combustible component is 52.1% and ash is 7.7% and for 3-components of sludge, moisture is 83.3%, combustible component is 7.7% and ash is 9%. The chemical element has the high order of carbon(51.6%), oxygen(38.6%), hydrogen(7%) on the dry basis of wastes. And the high heating value of MSW is 4989.4 Kcal/kg sludge is 4428.04 Kcal/kg and low heating value of the MSW which is measured by calorimeter is 2032.88kcal/kg. From the leaching test of wastes, there is no heavy metals.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2003.05a
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• pp.94-97
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• 2003

본 연구에서는 반도체제조에 필수적으로 사용되는 플라즈마장비의 성능을 예측.분석하여 개발 시간 및 비용의 절감과 장비의 성능을 극대화 할 수 있도록 이론적 전산모사 환경(VIP-SEPCAD)을 개발하고 있다. VIP-SEPCAD는 플라즈마의 물리.화학적 특성을 예측하는 plasma model, 중성화학종들의 반응 및 유돈 특성을 예측하는 neutral reaction-transport model, particle의 유동 특성을 예측하는 particle transport model, particle의 생성 및 성장 특성을 예측하는 particle formation-growth model, 식각 또는 증착되는 웨이퍼 표면변화를 예측하는 surface evolution model로 구성되어 있다. 현재 개발된 VIP-SEPCAD를 이용하여 산소 플라즈마의 특성과 각종 화학성분들의 분포를 예측하고 particle의 거동에 대하여 분석하였다.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.05a
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• pp.202-205
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• 2004

살라미 시료에서의 식염 및 일반성분 함량은 저장 기간과 온도에 따른 차이는 나타나지 않았다. 일반성분 살라미 시료의 pH와 수분활성도는 4.79와 0.911이었는데 저장 기간 중 pH는 상승하는 대신 수분활성도는 감소하는 경향을 보였다. 살라미는 진공포장하였음에도 불구하고 산화적인 지방과 단백질의 분해는 서서히 진행되었음이 확인되었다. 이러한 변화는 높은 온도에서 더 뚜렷하게 일어났다. 색도 $25^{\circ}C$ 저장된 시료에서 적색도와 황색도가 증가하고 밝은 색이 감퇴하는 현상이 $10^{\circ}C$ 저장 시료에서 보다 더 뚜렷하게 나타났다.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1994.05a
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• pp.34-54
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• 1994

1. 고형배지특성 (1) 물리화학성 토양재배에서는 토양이 갖고 있는 다양한 완충작용, 즉 보수, 통기성, 비료성분의 보유능력이 대단히 높기 때문에 연작장해가 없는 한 작물생산에서 안정적 생산이 가능하다. 반면에 양액재배에서는 이러한 완충능을 기대하기가 어렵다. 특히 배지에 따른 물리화학성의 차이가 있고 이들 배지의 활용을 근본적으로 근권환경의 제어라는 측면에서 기존의 토양재배보다 높은 생산성과 고품질을 요구하고 있는 실정이기 때문에 배지에 따른 적정 근권환경제어가 필요하다. (중략)

• Journal of Ginseng Research
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• v.15 no.3
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• pp.224-230
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• 1991

The seven traditional quality factors including age and root weight ect. were reviewed in relation to the chemical components as a new quality factor and pharmacological data. The other important factor, production place, appeared to be sum of the eight factors. The important of production place indicated that the best quality ginseng is produced in the optimum environment. The description of ginseng for medicinal use in present materia medica missed most traditional quality factors only indicating the change by processing. Such phenomena do not mean the significant of raw$.$ ginseng quality. since appropriate raw ginseng was supplied in traditional way. For the generation with analytical attitude the description of raw ginseng quality to the processed ginseng products is recommendable. For the quality control with biologically active or index compound, the composition of various compounds seems to be the best. The establishment of physical and chemical quality creteria that will match with the traditional mothod it needed and will accomplished by comparative research on raw ginseng from various production sites and growth conditions. The description of production-place, grade and quantity of raw ginseng to the processed products will give better information and higher popularity of products to consumers.