• Journal of the Korean Society of Food Science and Nutrition
• /
• 제31권4호
• /
• pp.658-663
• /
• 2002

The purpose of this study was to investigate the effect of iron supplementation on utilizations of various minerals, Ca, Mg, Na, K, Fe, Cu, Zn. Intakes, serum levels, and excretions of these minerals were analyzed and compared in rats fed diet with 100, 200, 400% of iron requirement (Fe, 2Fe, 4Fe groups) for 6 weeks. The feed intake, body weight gain and feed efficiency ratio were not significantly different among the groups. Serum Fe of 2Fe group was significantly lower than other two groups, and serum Zn of 4Fe group was highest. Mineral intakes were not significantly different among three groups. With iron supplementation, urinary excretions of Ca, Fe, Cu, Zn were elevated, but fecal excretions of minerals were not significantly different. And the daily retentions of Na and Fe were significantly elevated, but apparent absorbabilities of minerals were not significantly different. In summary, according to iron supplementation, mineral absorbabilities were not different but urinary excretions of some minerals were increased. Therefore, it could be suggested that adequate iron intake and well-balanced diet are more desirable than nutrient supplementation for mineral balance.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• 제7권3호
• /
• pp.465-470
• /
• 2006

Coating are needed on ophthalmic lenses to enhance both the mechanical durability of the relatively soft plastic surface and the optical performance of lenses. Organic-inorganic hybrid materials as molar ratio of 3-glycidoxypropyltrimethoxysilane(GPTS), methyltrimethoxysilane(MTMS) and tetraethyl orthosilicate(TEOS) were used to improve the surface characteristics and the optical properties on allyl diglycol carbonate lenses. Coating for these plastics were at $140^{\circ}C$ for 4hrs, applied using the sol-grl process flow-coating technique. The coated lens properties of transmittance, adhesion, pencil hardness, abrasion resistance, hot water resistance and chemical resistance were investigated. The optimum properties was obtained when the ratio of GPTS : MTMS : TEOS was 1:1:2, respectively.

• Proceedings of the KAIS Fall Conference
• /
• 한국산학기술학회 2009년도 춘계학술발표논문집
• /
• pp.372-375
• /
• 2009

반도체 봉지재란 실리콘 칩, 골드와이어, 리드프레임 등의 반도체 소지를 열, 수분, 충격으로부터 보호하기 위해 밀봉하는 재료로서 EMC(Epoxy Moding Compound)가 가장 많이 쓰인다. EMC는 기계적, 전기적 성능향상을 위한 무기재료로 실리카(Silica), 열에 의해 경화되어 3차원 경화구조를 형성하는 에폭시수지, 빠른 경화특성을 부여하기 위한 경화제로서의 페놀수지, 유기재료와 무기재료 사이의 결합력을 높이기 위해 커플링제, 카본블랙, 이형성 확보를 위한 왁스(Wax), 착색제(Colorant), 난연제(Flame Retardant)등의 첨가제로 구성되는 복합소재로써 본 연구에서는 에폭시의 유형에 따른 용융 실리카를 주충진재로 하여 각각의 봉지재의 첨가제를 기준으로 할 때 다양한 형태의 친환경 비할로겐계 반응형 난연제를 합성하는 기술을 개발하고 비 할로겐계 및 Sb 계 첨가형 난연제의 혼용 배합을 통해 친환경 EMC용 난연제의 제조기술을 개발하였다. 이들 EMC의 요구특성은 요구특성은 외부환경으로부터 칩 보호, 칩을 전기적으로 절연특성 유지, 칩의 작동시 발생되는 열의 효과적인 방출 특성 유지, 실장(Board Mounting)의 간편성 특성을 확보해야 하는 특성을 지니고 있어 이들 요구특성에 적합한 특성조사가 함께 이루어졌다.

• Journal of the Korean Magnetics Society
• /
• 제24권4호
• /
• pp.114-122
• /
• 2014

Since 1990, Agency for Defense Development (ADD) has been operating the nonmagnetic laboratory and the magnetic sensors laboratory to develop the key technology of the ship's magnetic silencing and to research the high performance magnetic sensors used in the weapon system and to perform the technical support for Republic of Korea Navy. Recently, the main test equipment in the laboratories has been upgraded to improve the measurement and analysis abilities against magnetic target and to evaluate the performance of the magnetic sensors. In this paper, the capability and the current state of magnetic test facilities of ADD are described.

• Prospectives of Industrial Chemistry
• /
• 제23권5호
• /
• pp.21-32
• /
• 2020

유기전자소자는 용액공정을 통한 대량생산이 가능하기 때문에 기존 무기전자소자에 비해 제조비용이 저렴하고 대면적 생산이 가능하며, 유기분자의 본연 특징으로 인해 유연하고 가벼운 소자를 구현할 수 있다. 그러나 무기 반도체에 비하여 현저히 낮은 전하이동도 특성은 유기전자소자의 상용화에 걸림돌이 되고 있다. 따라서 공액고분자의 결정화도, 모폴로지, 분자배향 최적화를 통한 자기조립 박막 제조는 전하이동을 원활히 하기 때문에 유기전자소자의 개발에 필수적이다. 본 기고에서는 유기전자소자의 활성층으로 사용되는 공액고분자의 자기조립을 유도하기 위한 다양한 특성을 갖는 용매 첨가제의 효과에 대해서 알아보고, 특히 첨가제의 용해도 계수가 공액고분자의 자기조립 거동에 미치는 영향에 대해 자세히 논의하고자 한다.

• Food Science and Preservation
• /
• 제20권1호
• /
• pp.88-96
• /
• 2013

This study was investigated to compare the major chemical components of kohlrabi (Brassica oleracea var. gongylodes) flesh and kohlrabi peel. Among the proximate compositions, the crude fat of kohlrabi peel contained lower than that of kohlrabi flesh, while the contents of carbohydrate and the crude protein were higher in the kohlrabi peel. Total free sugar content of the flesh kohlrabi was higher than that of the peeled kohlrabi, and the major free sugars of the flesh kohlrabi and peeled kohlrabi were identified as fructose and glucose. The value of glutamic acid was greater in amino acids of kohlrabi flesh and kohlrabi peel, and the contents of total amino acids and essential amino acids were higher in kohlrabi peel compared with kohlrabi flesh. Kohlrabi flesh also contained a higher level of unsaturated fatty acids than kohlrabi peel. The contents of organic acid were higher in kohlrabi peel, and the level of oxalic acid was the highest in both kohlrabi. The vitamin C contents of flesh kohlrabi and peeled kohlrabi were 231.36 mg/100 g and 402.75 mg/100 g, respectively. The mineral content of the peeled kohlrabi was higher than that of the flesh kohlrabi, and the mineral contents of the flesh and peeled kohlrabi were greater in the order of K>Ca>Mg>Na. As a result, the contents of total amino acid, essential amino acid, organic acid, vitamin C and mineral were higher in the peeled kohlrabi, and the free sugar and unsaturated fatty acid contents of the flesh kohlrabiwere higher.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• 제19권3호
• /
• pp.638-647
• /
• 2018

We have to prepare for the existing threats from North Korea and potential threats in the future. It is important to utilize our resources as effectively as possible to build military power that brings victory in a war. Based on a sustainable required operational capability, weapons systems at the acquisition stage need to maintain a combat-readiness posture and ensure operational sustainability. To achieve this, establishment of procedures that develop elements of depot maintenance at the beginning, which enables economical and effective depot maintenance during that stage, is essential. First, the requirement paper needs to develop the concept of the depot maintenance requirement through the pre-study outlined by this paper. Second, at the system development stage, a Development Plan of Depot Maintenance draft should be proposed. This is the initial paper that can develop the elements of depot maintenance, and it should be verified by a field test. Third, each force's logistics command should write a Depot Maintenance Direction draft and a Mid-term Requirement of Elements of Depot Maintenance draft with the proven Development Plan of Depot Maintenance draft. Also, the verified paper needs to be realized and renewed by the time the Requirement of Elements of Depot Maintenance draft is completed. In conclusion, the procedures explained above will contribute to build an economical and effective military power in a reality faced with a resource shortage and threats from the enemy.

• Journal of the Korean Recycled Construction Resources Institute
• /
• 제8권1호
• /
• pp.120-128
• /
• 2020

In this study, solid capsules using crystal growth-type inorganic materials that can be directly mixed with mortar were prepared. Thus, three levels of solid capsules were prepared. The prepared solid capsule was mixed with 3% of the cement mass, was evaluated quality and crack healing properties of the mortar. As a test results of the table flow and air content of the mortar mixed with the solid capsules showed that mix of the solid capsules was no effect on the table flow and air volume. As a test result of the crack healing properties of the mortar mixed with the solid capsule according to water flow test and crack closing test, the initial flow rate was decreased, it was confirmed that the reaction product occurred over time and the cracks were healed.

• Food Industry And Nutrition
• /
• 제20권2호
• /
• pp.8-12
• /
• 2015

나트륨(소금)의 경우 식품에 관능적 특성 부여 및 가공과정에 필수적인 물질이나 과다 섭취의 경우 고혈압 등 심혈관계 질환을 발생을 증가시키는 등 사회적인 문제가 되고 있다. 특히 한국인의 경우 장류, 젓갈 및 김치 등의 식품문화가 발달되어 WHO의 권장섭취량의 2배 이상 섭취하고 있는 실정이다. 나트륨 저감화의 경우 국민복지 향상, 의료비용 절감 및 사회적 편익비용 발생 등의 이유로 국가적 차원에서 나트륨 절감이 시급한 상황이다. 현재 식품의약품안전처 및 보건복지부 등에서 나트륨 저감화를 위한 다양한 정책 등을 추진하고 있다. 또한 세계적으로 무기염류 대체소금, 염미증진제 및 향미개선제 등의 개발 노력이 활발히 이루어지고 있는 상황이다. 그러나 낮은 관능적 특성 및 무기염류의 과량 사용에 관한 부작용 등으로 인하여 급증하는 소금대체 및 보완제 시장수요에 미치지 못하는 실정이다. 따라서 저염화 및 관능적으로 우수한 소금 대체소재 및 염미 증강물질 개발이 요구된다. 염미 및 지미상승 식물성 발효 조성물(SAP)의 경우 분리대두단백 등의 식물성 원료와 전통 장류의 제조원리를 응용한 염미증진제 또는 향미개선제이다. 관능적 특성을 조사한 결과 기존 사용되는 저염 소재에 비하여 염미 등의 관능적 특성이 우수하여 염미 및 관능적 특성 증진 소재로 활용 가능성이 높았으며 무기염류의 단점인 낮은 관능적 특성 및 무기염류에 의한 부작용 등의 우려가 없는 소재이다. 향후 염미 및 지미 상승 식물성 발효 조성물(SAP) 등의 활용방안 개발 및 적용분야 확대 등으로 국내 저염 식품 산업의 전반적 발전에 도움이 될 것으로 생각된다.

• Journal of Food Hygiene and Safety
• /
• 제15권4호
• /
• pp.344-350
• /
• 2000

This study was conducted to determine the content of inorganic metals in soft drinks distributed locally in markets.6 trace metals (Fe, Ca, Zn, Na, Mg, and K) were detected in 16 kinds of drinks,80 samples. The average concentration of inorganic metals in vegetable drinks was relatively higher than that of mixed drinks or carbonated drinks. The concentration of calcium, which is advisable inorganic metals for the growth of skeleton and the prevention of osteoporosis, hypertension, was very high and needed to be careful for the consumer who is suffer with lithiasis. Although carbonated drinks are very popular with the children and adolescence owing to the unbalance of the intake of Ca and P, habitual drinking could cause obstruction in skeletal growth and metabolism of Fe, Cu, and Zn. So, it is suggested that more practical study is needed fur the intake of inorganic metals.