• Resources Recycling
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• v.11 no.6
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• pp.18-23
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• 2002

A study on the solvent extraction of hexavalent chromium from aqueous solutions has been investigated. The results showed that the extraction efficiency of chromium increased in proportion to extractant concentration. Aliquat 336 of quarternary amine effectively extracted hexavalent chromium and was superior to Alamine 336. And the stabilizers like polyhydric alcohols of octanol, decanol and dodecanol showed the similar effect fur prevention of third phase and a little promotion of extraction efficiency in comparison with non-use of polyhydric alcohols. On the other hand, in solvent extraction of hexavalent chromium from aqueous solutions, the hexavalent chromium was completely extracted at pH range lower than 7 with 1% Aliquat 336 as extractant and 5% decanol as stabilizer and the hexavalent chromium in extractant was completely stripped with 1M sodium hydroxide solution in the stripping step.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10b
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• pp.416-418
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• 2000

본 논문에서는 컴퓨터 비전의 한 분야인 영상처리에 의한 물체인식을 위한 선행연구로써, 차량번호판 인식 시스템을 구현하기 위한 연구의 한 부분인 차량 번호판의 일련번호부분을 추출하는 방법을 기술한다. 이진화된 전체 차량 이미지의 일련번호영역을 추출하기 위해 레이블링기법과 번호판 일련번호의 특성 등 선행지식을 이용하여 번호판의 각 일련번호를 찾아서 분할하고 추출하는 알고리즘을 제안한다. 번호판영역을 찾는 동시에 분할하고 추출해 줌으로써 복잡한 여러 알고리즘을 사용하지 않고도 비교적 정확히 번호판의 일련번호를 추출할 수 있고, 속도면에서도 상당히 우수한 결과를 보여준다.

• Resources Recycling
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• v.22 no.2
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• pp.3-10
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• 2013

Indium is one of the rare metals, and it has been used mainly for preparation of indium tin oxide (ITO). This review investigated the process parameters and the merits and demerits of several methods to recover indium from the leaching solution of secondary resources, such as solvent extraction, ion exchange, and precipitation. D2EHPA has been used mostly as a cationic extractant for indium extraction in moderate acid solutions, while amine extractants are used in strong hydrochloric acid solution. Since the loading capacity of resins for indium is generally small, ion exchange has some advantage over solvent extraction only when the concentration of indium is low.

• Korean Chemical Engineering Research
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• v.43 no.3
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• pp.380-386
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• 2005

Separation of fructose and glucose was performed using emulsion liquid membranes with a mixture of an organoboronic acid and a quaternary ammonium salt as a carrier in a batch reactor. In order to find a carrier and an optimal experimental condition suitable to the sugar separation, extraction of each sugar was carried out independently. The effect of various experimental variables, such as initial concentration of sugar in the feed phase, type of organoboronic acids, and w/o ratio, on the sugar separation was investigated, and the concentrations of sugars in each aqueous phase were analyzed. The ratio of degree of extraction of fructose to that of glucose was very high, but the concentration of fructose in the receiving phase was not too high. Therefore, a stronger stripping agent in the receiving phase was required for development of a practical ELM system suitable to the sugar separation.

• Korean Journal of Food Science and Technology
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• v.43 no.2
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• pp.200-205
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• 2011

In this study, antioxidant and anti-inflammatory effects of ethanol extracts from medicinal herb mixtures were investigated in vitro. Contents of total polyphenols in ethanol extracts from Houttuynia cordata Thunb. (HC), Carthamus tinctorius L. (CT), and MIX-2 (Houttuynia cordata Thunb., Acanthopanax gracilistylus Smith, Carthamus tinctorius L., Kalopanax pictus) were 58.98, 60.79 and 57.74 mg/g respectively. Radical scavenging activities of the ethanol extracts were examined using ${\alpha},{\alpha}$-diphenyl-${\beta}$-picrylhydrazyl radicals and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) assay. Anti-inflammatory effects of ethanol extracts from medicinal herbs composites were examined using 5-lipoxygenase (5-LO), cyclooxygenase-2 (COX-2) and nitric oxide (NO) inhibition assays. The ethanol extracts from medicinal herb mixtures showed higher 5-LO and COX-2 inhibition activities than those from single medicinal herbs. The ethanol extracts from medicinal herb mixtures also showed strong anti-inflammatory activity through inhibition of NO production.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.69-76
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• 1998

This study was investigated to determine the effect of additives and ionic strength on the functionality of extracted proteins in preblends in order to use less additive in restructured meat products. Preblends contained the combinations of sodium chloride (NaCl; 0, 4.5, 9.0%), sodium tripolyphosphate (STPP; 0, 2.5, 5.0%), and tetrasodium pyrophosphate (PP; 0, 2.44, 4.88%). The pH values increased linearly with increasing STPP and PP concentrations (p<0.01). In the equivalent ionic strengths, PP was more effective than STPP in increasing pH. Phosphate ions were more effective on total extractable protein (used 1 M NaCl buffer) than chloride ion at equivalent ionic strengths. Solubility was decreased by adding NaCl and increasing total extractable proteins. Meat sulfhydryl contents were high with increasing total extractable proteins. When protein extracts were heated at $65^{\circ}C$, 7 min, meat sulfhydryl contents decreased and surface hydrophobicity increased (p<0.01). However, all protein extracts showed no differences in SDS-PAGE pattern. In conclusion, PP is more effective than STPP in order to use less additive but there was no linear relationship between functionnal improvement and ionic strength.

• Journal of the Korean Applied Science and Technology
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• v.36 no.3
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• pp.821-829
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• 2019

This study was conducted to evaluate the applicability of the extracts from nipa palm, molokhia, and finger root in functional cosmetics as a natural active ingredient. The extracts were obtained through the processes of heating under reflux with ethanol, filtration, concentration, and freeze-drying. UV absorption and blocking effects of the extracts were examined by using the UV-vis spectrophotometer equipped with an integrating sphere. Antioxidant activity and its stability between the extracts were compared using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay. Also, total polyphenol content in the extracts was determined quantitatively using the Folin-Ciocalteu reagent, with gallic acid as the standard. Antibacterial activity of the extracts was investigated by the disc diffusion test against Staphylococcus aureus (gram-positive) and Escherichia coli (gram-negative). Finally, collagenase inhibitor assay was performed to examine the anti-wrinkle effect of the extracts. From the results of this study, the extract of nipa palm showed the potential for use in cosmetics as an antioxidant and anti-wrinkle agent, and the extract of finger root as a sunscreen and antibacterial agent.

• Applied Chemistry for Engineering
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• v.7 no.6
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• pp.1053-1060
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• 1996

$\beta$-ketohexanal as a chelating extractant was synthesized from the reaction of ethyl formate and methyl propyl ketone in the presence of sodium amide, and the equilibrium characteristics in the extraction of copper by $\beta$-ketohexanal-chloroform were investigated. The equilibrium constants such as the dissociation constant and the partition coefficients of $\beta$-ketohexanal, the stability constant and the partition coefficient of copper chelating complex, and the overall equilibrium constant in the extraction of copper were determined by spectrophotometric measurements, and the mechanism of extraction was proposed. The percent of extracted copper by $\beta$-ketohexanal-chloroform was near 100%, and the selective extraction of copper from Cu-Zn-Cd mixture was possible. Copper was found to be extracted as $CuR_2$ and the equilibrium reaction was expressed as $Cu^{2+}+2{\overline{HR}}{\rightleftarrows}{\overline{CuR{_2}}}+2H^+$.

• The Journal of Korean Medicine
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• v.23 no.3
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• pp.164-173
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• 2002

목적：반응성산소기들은 장관에서 여러 종류의 질병의 발생과 관련을 가지고 있는 것으로 알려져 있어, 이들에 의한 세포손상을 방지하는 약물의 개발은 시급한 실정이다. 본 연구에서는 항산화작용을 가진 약재로 보고 된 단삼추출액이 장관상피세포에서 $H_2O_2$에 의한 세포손상을 방지할 수 있는 지를 조사하고자 하였다. 방법：장관상피세포로는 사람의 소장상피세포에서 유래한 배양세포주인 Caco-2세포를 이용하였고, 세포손상 정도는 trypan blue exclusion assay를 통해 평가하였고, 지질의 과산화는 그 산물인 malondialdehyde의 량을 측정하여 산정하였다. 결과： $H_2O_2$는 처리 시간 및 농도에 비례하여 세포손상을 유발하였으며, 이러한 효과는 단삼추출액에 의해 농도의존적으로 방지되었다. $H_2O_2$에 의한 세포소상은 $H_2O_2$제거제인 catalase와 철착염제인 deferoxamine에 의해 방지되었으나 항산화제인 N,N-diphenyl-p-phenylenamine(DPPD)에 의해 영향을 받지 않았다. $H_2O_2$는 지질의 과산화를 증가시켰으며, 이러한 효과는 단삼추출액과 DPPD에 의해 억제되었다. 단삼추출액은 $H_2O_2$에 의한 세포내 ATP 고갈을 방지하였다. $H_2O_2$는 DNA 손상을 일으켰으며, 이러한 효과는 단삼추출액, catalase 및 deferoxamine에 의해 방지되었으나, DPPD에 의해서는 변화되지 않았다. 결론 : 이상의 결과를 종합하면 단삼추출액은 장관상피세포에서 $H_2O_2$에 의한 세포손상을 방지하며, 이러한 효과는 항산화작용이 아닌 다른 작용기전에 기인할 것으로 생각된다. 또한 본 연구의 결과는 $H_2O_2$가 장관상피세포에서 지질의 과산화를 유발하여 세포손상을 일으키지 않음을 가리킨다.

• Korean Journal of Microbiology
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• v.52 no.3
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• pp.380-382
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• 2016

Chungkookjang, fermented soybeans, contains diverse peptides produced during fermentation. Fermented soybean extracts containing the peptides can affect cellular signal transduction. Proliferation of human breast cancer MDA-MB-231 cells were repressed dependent on concentrations of fermented soybean extracts. Since fermented soybean extracts inhibited breast cancer cell's growth, and inflammation is related to cancer, it is determined whether it can suppress inflammatory $TNF{\alpha}$ expression. $TNF{\alpha}$ expression in MDA-MB 231 cells treated with fermented soybean extracts was repressed by that extracts. $TNF{\alpha}$ inhibitors were developed as drugs for autoimmune diseases. Since fermented soybean extracts suppressed $TNF{\alpha}$ expression, it can be developed as those drugs.