• The Journal of Natural Sciences
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• v.8 no.2
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• pp.49-55
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• 1996

In order to survey the safety of some food additives, antimicrobial activity of acidulants, stabilizers, antioxidants, natural coloring materials and bleaching agents against 5 strains of bacteria and Sacch. cerevisiae were investigated by dilution method and minimal inhibitory concentration(MIC) method. Malic acid as acidulants displayed the effective antimicrobial activity in vitro against P. aeruginosa and its MIC is 0.05%. Alginic acid and pectin as stabilizer also displayed strong antimicrobial activity against B. subtilis, E. coli and P. aeruginosa, and tannin(antioxidants) and $NaHSO_3$ displayed antimicrobial activity against all bacteria tested. However gums(Arabia, Xanthan, Gua) and natural coloring materials(Hongwha Yellow, Red powder-N) were not affected to growth of bacteria and Sacch. cerevisiae.

• Journal of the Korean Electrochemical Society
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• v.5 no.2
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• pp.52-56
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• 2002

Tin oxide was coated on graphite particle by sol-gel method and an electrode with this material having microcrystalline structure for lithium ion battery was obtained by heat treatment in the range $400-600^{\circ}C$. The content of tin oxide was controlled within the range of $2.25wt\%\~11.1wt\%$. The discharge capacity increased with the content of tin oxide and also initial irreversible capacity increased. The discharge capacity of tin oxide electrode showed more than 350 mAh/g at the initial cycle and 300 mAh/g after the 30th cycle in propylene carbonate(PC) based electrolyte whereas graphite electrode without surface modification showed 140 mAh/g. When the charge and discharge rate was changed from C/5 to C/2, The discharge capacity of tin oxide and graphite electrode showed $92\%\;and\;77\%$ of initial capacity, respectively. It has been considered that such an enhancement of electrode characteristics was caused because lithium $oxide(Li_2O)$ passive film formed from the reaction between tin oxide and lithium ion prevented the exfoliation of graphite electrode and also reduced tin enhanced the electrical conduction between graphite particles to improve the current distribution of electrode.

• Journal of the Korean Chemical Society
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• v.25 no.5
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• pp.306-310
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• 1981

Induced circular dichroism spectra of racemic cobalt(III) complexes for $[Co(en)_3]^{3+},\;[Co(tn_)3]^{3+},\;cis-[Co(NH_3)(en)_2]^{3+},\;[Co({\beta}-ala)(en)2_]^{2+},\;[Co(gly)(en)_2]^{2+}\;and\;[Co(acac)(en)_2]^{2+}$ were measured when they were dissolved in aqueous d-tartrate2- solution at room temperature. Only a single negative CD spectrum was observed for all the complexes above in visible region(400∼500nm). It was interpreted that these CD bands were attributed to the difference in interaction between ${\Lambda}$-and ${\Delta}$-enantiomers with d-tartrate$^{2-}$. Namely, when d-tartrate$^{2-}$ was added to ${\Lambda}$-enantiomer and ${\Delta}$-enantiomer, it caused ${\Lambda}$-enantiomer to change greatly and ${\Delta}$-enantiomer to change only slightly; combined the results proved induced circular dichroism. The enantiomer for which the eluent has a stronger affinity should be eluted faster in ion-exchange column chromatography. It is possible to predict the elution order of chromatography from the sign of the induced CD if stronger interaction of chiral anion with the complex leads to greater change in the natural CD spectrum of the complex. The elution order was in complete agreement with the prediction from the sign of the induced CD spectrum for all the measured complexes.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2005.11a
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• pp.144-146
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• 2005

• Proceedings of the Korean Information Science Society Conference
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• 2007.06b
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• pp.9-14
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• 2007

단백질 분류는 현대 생물학의 큰 도전과제이다. 현재 여러 단체에 의해 잘 관리되는 상세한 주석이 달린 많은 양의 단백질 정보들이 존재한다. 이러한 데이터베이스의 덕분으로 다양한 물리 화학적 특성과 주석들에 기반하고 있는 분류 기법들이 연구되고 있다. 특히 아미노산들로 이루어진 단백질 서열이 해당 단백질의 분류에 중요한 역할을 하는 진화적 기록들의 단서가 되기 때문에 단백질 서열들에 대한 연구가 활성화되고 있다. 비록 단백질 서열이 단백질 분류 문제의 중요한 특징이 된다고 해도 단순한 단백질 서열만으론 해당 단백질에 대한 충분한 정보를 얻을 수 없으며, 타 종 간에도 기능상 유사성 때문에 서로 비슷하게 판별될 수 있다. 이러한 문제점에 착안해서 우리는 오토마타 종 분류기라고 부르는 새로운 시스템적인 종 분류 접근 방법을 제안한다. 이 시스템의 클러스터링과 종 분류 판별 성능에 대한 평가 실험을 수행해본 결과 상대적으로 좋은 성능을 얻을 수 있었다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.148-149
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• 2007

현재 전자부품 시장은 RoHS 규정으로 인하여 lead free화가 진행되고 있으며 많은 주목을 받고 있다. 본 논문에서는 반도체 패키지 및 부품표면일장에서 사용 되는 무전해 주석 도금과정 중 산 탈지 후 막의 표면 거칠기 정도가 도금 후의 표면 거칠기 정도에 미치는 영향을 평가 한다. 실험의 효율성을 높이기 위해 통계적인 실험계획법을 사용하였으며 실험의 횟수를 줄이고 표면 거칠기 정도는 이미지 프로세싱을 통하여 분석하였으며 통계적인 모델링을 통해 micro etch가 도금 표면의 거칠기에 주는 영향을 분석하였다.

• The KIPS Transactions:PartD
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• v.12D no.1 s.97
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• pp.51-62
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• 2005

After figuring out the function of an amino acid sequence, we can infer the function of the other amino acids that have similar sequence composition. Besides, it is possible that we alter protein whose function we know, into useful protein using genetic engineering method. In this process. an original protein amino sequence produces various protein sequences that have different sequence composition. Here, a systematic technique is needed to manage protein version sequences and reference data of those sequences. Thus, in this paper we proposed a technique of managing protein version sequences based on local sequence alignment and a technique of managing protein historical reference data using Trigger This method automatically determines the similarity between an original sequence and each version sequence while the protein version sequences are stored into database. When this technique is employed, the storage space that stores protein sequences is also reduced. After storing the historical information of protein and analyzing the change of protein sequence, we expect that a new useful protein and drug are able to be discovered based on analysis of version sequence.

• The Korean Journal of Food And Nutrition
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• v.23 no.2
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• pp.226-232
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• 2010

새로운 항치매성 건강식품을 개발하기 위해 아세틸콜린에스터레이즈(AChE)를 강력하게 저해하는 추출물을 곡류와 두류의 다양한 추출물로부터 선발한 후 최적 추출 조건을 조사하였다. 추출물 중 수수 메탄올 추출물이 63.4%의 가장 높은 AChE 저해 활성을 보였다. 수수를 80% 메탄올로 $40^{\circ}C$에서 12시간 추출했을 때 최대의 AChE 저해 활성을 나타내었다. AChE를 저해하는 수수 메탄올 추출물의 영양성과 생리 기능성을 조사하였다. 메탄올 추출물은 유리당으로 고형물 100 g당 4.78 g의 포도당과 4.13 g의 자당 및 0.97 g의 과당을 함유하였다. 또한, 수수 메탄올 추출물의 고형물 100 g에 linoleic acid 273.82 mg, oleic acid 215.65 mg, palmitic acid 122.03 mg, stearic acid 4.96 mg을 함유하고 있었고, 주요 유기산으로 주석산 27.45 mg, 말론산 15.43 mg, 사과산 9.94 mg이 메탄올 추출물 1 g에 함유되어 있었다. 수수 메탄올 추출물은 항치매 활성 외에도 콜레스테롤 합성을 저해하는 HMG-CoA reductase 저해 활성이 50.2%이었고, 항산화 활성은 56.1%를 보였다.

• Journal of Convergence for Information Technology
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• v.11 no.12
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• pp.221-228
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• 2021

In this work, the post-treatment using organic acids during hair dyeing process was used to maintain hair color and to decrease hair damage. The effect of post-treatment using succinic acid and tartaric acid during hair dyeing process with cherry red and blue silver color on the persistence of hair color, tensile strength of hair, hair porosity, and surface characteristics of hair was investigated. After the repeated shampooing process, the experimental group with succinic acid and tartaric acid could more efficiently maintain the hair color than control group. The experimental group with succinic acid and tartaric acid could also increase the tensile strength of hair, decrease the hair porosity, and smoothen the hair surface, compared with control group. Particularly, tartaric acid was able to maintain the color of the dyed hair and protect the hair with higher efficiency than succinic acid.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.7
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• pp.1016-1027
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• 2015

This study collected 120 figs, classified them into six degrees of maturity according to hardness values, and analyzed contents of organic acids and free sugars. Volatile compounds in figs were investigated using the solid-phase microextraction method of gas chromatography/mass spectrometry. For measurement of texture, elasticity increased up to stage 4 and decreased again. Cohesiveness and brittleness increased with maturation. Organic acids in figs were mainly composed of citric acid, malic acid, and tartaric acid in the final stage. Fructose and glucose were the major sugar components of figs. Fructose content decreased from stage 1 to stage 4 and then increased significantly. One hundred and nineteen volatile compounds were identified in figs, and classes were 14 acids, 15 alcohols, 23 aldehydes, 10 esters, 33 hydrocarbons, 11 ketones, four aromatics, six miscellaneous, and five terpenes. The dominant volatile components in figs were hexadecanoic acid, hexane, dodecanal, DL-limonene, 2-hexanal, nonanal, and 6-methyl-5-hepten-2-one.