• Korean Journal of Human Ecology
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• v.2 no.2
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• pp.29-38
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• 1999

저항전분(RS)은 건강한 사람의 소장에서 소화되지 않는 전분이나 전분질 식품의 부분이다. 저항전분은 4가지 형태로 구분하는데 RS 1은 물리적으로 효소와 만나지 않는 부분, RS 2는 생전분으로 감자, 바나나와 고아밀로오스 옥수수전분, RS 3는 노화된 전분 그리고 RS 4는 화학적으로 변성시킨 전분이다. RS 함량은 열에 안정한 $\alpha$ -아밀라아제나 pancreatin, pancreatic $\alpha$ -아밀라아제와 미생물에서 분리된 아밀라아제 등을 이용한 몇 가지 방법에 의해 분석되고 있다. RS는 대장에서 미생물에 의해 발효되어 단쇄지방산을 생성하는데 특히 부티릭산이 생성된다. 아세트산이나 프로피온산은 간의 대사에 영향을 주며 부티릭산은 항 종양(항 대장암) 특성이 있다. RS는 소화가 되지 않아 저열량원이므로 당뇨병 환자나 운동에 의한 혈당 조절이 필요할 때 조절능력을 갖는다. RS가 건강에 중요한 인자임이 알려지면, 건강을 위해 매일 섭취량의 증가를 권장해야 할 것이다.

• Journal of the Korean Chemical Society
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• v.29 no.4
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• pp.437-440
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• 1985

Organic azides were reduced to organic amines in the presence of tetracarbonylhydridoferrate(O) as a highly selective reducing agent at room temperature under carbon monoxide atmosphere. Particularly, benzoylazide gave ethylphenylcarbamate at room temperature but gave benzamide quantitatively at -40$^{\circ}$ in the presence of tetracarbonylhydridoferrate under carbon monoxide atmosphere.

• The tire
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• s.46
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• pp.7-12
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• 1973

자동차타어어가 상품인이상 경제효율을 도외시 하고선 만들수가 없다. 그래서 더욱 성능이 높은 타이어를 어떻게 해서 싸게 만들수 있느냐 가 큰문제로 된다. 한때는 가장 손이 많이드는 성형부문의 합리화가 타이어 매스푸로화에의 큰 과제이였다. 그것이 잇따라서 가류부문에도 파급했다. 여기에 등장하는것이 자동성형기 이기도 하고 백오마틱푸래쓰이 기도 했으나 그것들이 오늘날의 타이어제조의 전부는 아니다. 3류배우적 이기는 하나 가류촉진제의 이룩한 쳑할의 중요성도 잊어서는 안된다고 생각한다. 그래서 금번은 타이어 약품의 대상인 화학회사 가우화학(주)에 부탁해서 가류촉진제와 노화방지제를 중심으로 각종의 해설을 구했다. 이에 의하면 가류촉진제가 발견되어서 70년 그 진보에는 현저한것이 있었으나 챠알스 굳이어가 133년전에 발견한 류황을 사용해서의 가류법이 상금사용되고 있는 한 금후특히 괄목할 타이어 약품의 출현도 곤란할 것 같다고 하고 있다. 따라서 약품매이커어로서는 더욱 고도화에의 노력은 해도 고무 그 자체를 다르게 한다거나 타이어의 제조법을 근본적으로 개조하지 않는 한에 있어서는 말이다.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.288-294
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• 1994

Dietary fiber contents in brans of the two representative Korean rice varieties, Chucheong and Sucheon were measured by the AOAC method, and the composition of total dietary fiber (TDF) was analyzed with the acid detergent fiber (ADF) procedure. Rice bran contained more than 25% of TDF, most of which was insoluble dietary fiber. Hemicellulose was shown to be the major constituent and rice bran dietary fiber contained distinctive amounts of cellulose and uronic acid. Consecutive acidalkaline treatment of rice bran considerably increased soluble dietary fiber (SDF) content and water-holding capacity (WHC). WHC of wheat flour-rice bran dietary fiber mixture increased with the proportion of rice bran dietary fiber. Analysis of the differential scanning calorimetry thermograms revealed that rice bran dietary fiber effectively retarded retrogradation of wheat starch.

• Korean Journal of Food Science and Technology
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• v.41 no.6
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• pp.700-705
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• 2009

Several studies have demonstrated that chlorophyll has many beneficial properties, including anti-inflammatory, anti-tumor, and antioxidant properties. Chlorophyll has been also shown to have an excellent chemopreventive potential against skin tumor. Its preventive mechanism against skin tumor, however, has not been examined in detail. Furthermore, the effects of chlorophyll on UVB-induced cellular responses have not been investigated. Solar UV radiation, in particular its UVB component, is the primary cause of many adverse biological effects, which is responsible for the photoaging and skin cancer. We investigated the preventive effects of chlorophyll a on UVB-mediated responses in human immortalized HaCaT kerationocytes and normal human fibroblast. We found that treatment of chlorophyll a markedly inhibited UVB-induced generation of reactive oxygen species and lipid peroxidation. Chlorophyll a also prevented UVB-induced MMP-1 expression and MMP-2 activation and increased Type I pN collagen synthesis. These results suggest that chlorophyll a is a potent candidate for the prevention and treatment of UVB-induced skin cancer and photoaging.

• Applied Biological Chemistry
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• v.46 no.1
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• pp.60-65
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• 2003

MMP-1 inhibitory compounds were isolated from 120 Korean traditional edible plants. UP- 1 activity significantly increased linearly with increasing UVB dose in normal human foreskin fibroblast HS68 cell, showing maximum activity at approximately 35 $mJ/cm^2$, whereas in HaCaT cell, normal human keratinocyte, no increase was observed. Maximum secretion of MMP-1 after UVB treatment occurred around 36-48 k after treatment. MMP-1 inhibitory compound isolated from cold-water fraction of Cataegus pinnatifida Bunge showed the mort potent activity. The MMP-1 inhibitory compound was deduced as a peptide based on the fact that pronase digestion decreased the activity whereas periodate oxidation did not. The most potent UP- 1-inhibitory protein, CP-2Va-2, showing an activity of 88.5% against MMP-1, was isolated through sequential column chromatography on DEAE-Toyopearl 650C, Butyl-Toyopearl 650M, and Bio-Gel P-30. Molecular weight of CP-2Va-2 determined through high performance liquid chromatography and SDS PACE was 19 and 20 kDa. respectively, signifying a monomeric structure.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.7
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• pp.731-737
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• 2006

Four well-characterized soils collected from A- and B-horizon in the Department of Energy Oak Ridge Reservation in USA, mainly distributed with Inceptisol(Inc) and Ultisol(Ult) soils, were used in this work. The bioaccessibility of arsenic as well as oxidation phenomena of As(III) was investigated with soils spiked with As(III) and As(V) using a physiologically based extraction test(PBET) at pH 1.5 and 1:100 soil to solution ratio. Also effect of aging time on the bioaccessibility of arsenic was investigated over the 6 months. After 48 hours(fresh) contacting As(V) solution with soils, all soils rapidly and strongly sequestrated As(V), especially Ult-B. However, little sequestration was observed after 3-months. When As(III) was spiked on the same soils, a great portion of As(III) was oxidized to As(V) after 48 hrs, especially Inc-A and Ult-A soils, which is strongly related with Mn content in soils. By using As(III)-spiked soils, much reduced bioaccessibility as total arsenic was observed from Inc-B and Ult-B soils over the 6 months aging time compared to that from Inc-A and Ult-A soils. This result can be explained by the continuous sequestration of As(V), produced from oxidation of As(III), onto Inc-B and Ult-B soils having much amount of iron. The trend of As(III) sequestration over six months aging time was quite similar with that of As(V) sequestration.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.141.2-141.2
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• 2015

교류임피던스 측정기법을 이용하여 전기화학적으로 외부환경에서 소재 금속까지 물질 및 전하이동에 관한 임피던스 측정이 가능하며 도막의 부식 및 노화정도 및 내식성의 평가가 가능하여 산업체에서 널리 이용되고 있다. RPCS(Remote Plasma Cleaning Source)는 패널 및 반도체 제조공정에서 CVD 증착공정 후 챔버 내부에 입혀지는 Si(실리콘)을 화학적으로 세정하기 위한 F(불소) Radical을 공급하는 원격 고밀도 플라즈마를 발생시키는 제품이다. RPCS의 바디는 알루미늄을 사용하고 절연 및 플라즈마에 대한 내구성을 확보하기 위해 아노다이징 코팅을 한다. 반응기 내벽의 표면이 공정 플라즈마에 노출될 때 소재는 화학적으로 매우 활성이 높은 라디칼과의 반응뿐만 아니라 이온의 충격을 동시에 받게 되며 이 과정에서 다량의 불소 (Fluorine) 라디칼과 전계에 반응한 이온의 운동에 노출되면서 아노다이징 코팅이 손상되는데 이는 기기의 수명 단축 및 파티클을 발생시키며, Arc의 원인이 되기도 한다. 실제 사용 환경에서는 기기의 분해 없이 아노다이징의 상태를 주기적으로 모니터링 하기가 대단히 어려워, 정기적으로 교체하고 있는 실정이다. 본 연구에서는 RPCS내 발생된 플라즈마 현상을 컨덕터로 활용하여 고주파 리액턴스를 임피던스로 환산하여 아노다이징 코팅의 손상 정도를 진단 및 모니터링하였다. 아노다이징이 손상된 내부 블럭과 정상상태인 내부 블럭의 임피던스를 비교하였고, 아노다이징 두께별 임피던스를 측정하였다. 그 결과 아노다이징 절연막이 손상된 블록의 임피던스가 정상 블록에 비해 낮았으며 두께별 임피던스도 비례함을 알 수 있었다. 향후에는 장기간 현장에서 축척되어진 시험데이터를 바탕으로 아노다이징 코팅의 수명예측진단 시스템을 구축하고자 한다.

• Journal of the Korean Chemical Society
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• v.42 no.6
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• pp.664-671
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• 1998

Poly pyrrole polymer(ppy) has an excellent electrical conductivity and can be easily polymerized on anode to give various morophology according to doped anion on electroactive sites. To improve the properties of brittleness, ageing and hydrophobisity, poly furan polymer(pfu) having a high initiation potential was anodically implanted in this porous ppy film matrix to get the Pt/ppy/pfu(x)type of polymer composite electrode. Cyclic voltammetry and electrochemical impedance methods were used to these electrode, where $PF_6^-,\; BF_4^-$, and $ClO_4^-$ ions were employed as dopants. The composition of the pfu(x) at the electrode was changed from 0 to 1.10, but the range was useful only at 0.1 to 0.2 as the redox electrode. The polymer composite electrode doped with $PF_6^-$ was better in charge transfer resistance by a factor of 40 times and in double layer capacitance by a factor of 20 times than others. The charge transfer in the polymer film of the electrode was influenced on frequency change and equivalent circuit of this electrode had Warburg impedance including mass transfer.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.2
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• pp.128-138
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• 1994

To improve seed vigour in rice, barley and soybean, several methods of presowing treatment, using chemicals and priming in polyethylene glycol solution, were investigated. Gibberellic acid($GA_3$) slightly improved germination of rice, but other chemical treatments showed no beneficial effect on seed vigour. Aged seeds were primed in polyethylene glycol solution then rinsed and germinated with drying back. In general mean germination time increased and percentage germination decreased with in- creasing water potential of the priming solution, but there were no significant effects on spread of germination times. Priming also showed no marked improvement in germination under cold, wet, or osmotic conditions. None of the treatments used was successful in practically improving the seed germination and vigour of the tested crops. However, seed treated with GA$_3$ gave the best overall germination response.