• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.140-143
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• 2001

A study has been made on the recovery of nitric acid and valuable metals such as Cu, Sn, Pb from the spent nitric etching solutions. The nitric acid was extracted effectively by TBP but the heavy metals such as Fe, Cu, Sn, Pb were not extracted by TBP from the spent nitric etching solutions. From the experimental results, 95% of nitric acid in spent etching solution was extracted at O:A ratio of 3:1 with five stage by 60% TBP and 98% of nitric acid was stripped from the loaded organic phase at O:A ratio of 1:1 with four stages by distilled water. After extracting nitric acid, Cu was recovered as a metal by electrowinning effectively and Sn was successfully removed by precipitation method by adjusting the pH of raffinate solution. Finally, Pb was recovered by cementation with iron scrap at $65^{\circ}C$. Parameters controlling the cementation process, such as temperature, pH and the effect of the additives were investigated.

• Journal of Acupuncture Research
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• 제27권3호
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• pp.65-73
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• 2010

Objectives : Recently, Pharmacopuncture therapy has been used for the treatment of inflammatory diseases such as rheumatoid arthritis. Especially, we have been interested in chemical mediators concerned with inflammation such as prostaglandin, nitric oxide. The purpose of this study is investigated that the effect of Ampelopsis Radix Pharmacopuncture solution in RAW 264.7 macrophages, performed several experimental items : those are Prostaglandin $E_2$, Nitric Oxide and Cyclooxygenase-2. Methods : The cytotoxicity of Ampelopsis Radix Pharmacopuncture solution in RAW 264.7 macrophages were measured by MTT assay. In order to observe cyclooxygenase-2 mRNA expression in lipopolysaccharide and interferon-gamma stimulated RAW 264.7 macrophages, RT-PCR was used. Prostaglandin $E_2$ production and Nitric Oxide production was measured by nitric oxide detection kit and Prostaglandin $E_2$ assay kit. Results : 1. The MTT assay demonstrated that cytotoxic effect of Ampelopsis Radix Pharmacopuncture solution in RAW 264.7 macrophages was not appeared. 2. Ampelopsis Radix Pharmacopuncture solution inhibited nitric oxide production in lipopolysaccharide and interferon-gamma stimulated RAW 264.7 macrophages. 3. Ampelopsis Radix Pharmacopuncture solution inhibited cyclooxygenase-2 mRNA expression in lipopolysaccharide and interferon-gamma stimulated RAW 264.7 macrophages. 4. Ampelopsis Radix Pharmacopuncture solution inhibited Prostaglandin $E_2$ production in lipopolysaccharide and interferon-gamma stimulated RAW 264.7 macrophages. Conclusions : On the basis of these results, It was shown that Ampelopsis Radix Pharmacopuncture solution was able to inhibit the production of $PGE_2$ and NO, as well as COX-2 mRNA expression. Our results may provide new mechanism by which Ampelopsis Radix Pharmacopuncture solution accounts for its beneficial effect on accelerating wound healing and anti-inflammation.

• 청정기술
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• 제9권2호
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• pp.57-61
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• 2003

금속가공 공정에서 알루미늄 합금소재의 알칼리 에칭 후 표면에 발생한 스머트(Smut) 를 제거하기 위해 무질산 디스머트(Nitric acid-free desmut) 용액을 개발하였다. 과산화수소(2%), 불산(0.5%) 및 황산(10%)을 혼합한 산용액이 NaOH 수용액에 처리한 A16061 및 A15052 규격의 알루미늄 합금 소재에 대한 스머트 제거효과가 5% 질산수용액의 사용할 경우와 유사하게 관찰되었다. 스머트 제거를 위한 혼합 산용액 처리 전 후 소재 표면을 SEM-EPMA 분석을 통해 확인하였다.

• 한국표면공학회지
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• 제49권3호
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• pp.231-237
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• 2016

This article reports a new chemical bath for preparing a mirror-like surface of AZ31 Mg alloy. In order to find an appropriate chemical polishing solution, four different acidic solutions of sulphuric acid, nitric acid, acetic acid and a specially designed mixture of nitric acid and acetic acid were investigated in view of the changes in surface appearance, roughness and dissolution rate of AZ31 Mg alloy. The surface scales on AZ31 Mg alloy were readily removed by all the acidic solutions, but a reflective surface was produced only by etching in the specially designed solution, and only after a specific etching time. The surface roughness increased with etching time in sulphuric acid, nitric acid, and acetic acid, but it lowered after a specific etching time in the specially designed mixture of nitric acid and acetic acid. Dissolution rate of the alloy in the specially designed mixture of nitric acid and acetic acid appeared to be more than twice than that in separate nitric acid or acetic acid. In this work, we recommend the mirror-like surface of AZ31 Mg alloy obtained by polishing for an optimum time in a mixture of nitric acid and acetic acid for following surface finishings, chemical conversion coating, electroplating, electrophoretic painting and anodizing treatment.

• Asian-Australasian Journal of Animal Sciences
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• 제28권11호
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• pp.1624-1628
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• 2015

Rigorously standardized laboratory protocols are essential for meaningful comparison of data from multiple sites. Considering that interactions of minerals with organic matrices may vary depending on the material nature, there could be peculiar demands for each material with respect to digestion procedure. Acid digestion procedures were evaluated using different nitric to perchloric acid ratios and one- or two-step digestion to estimate the concentration of calcium, phosphorus, magnesium, and zinc in samples of carcass, bone, excreta, concentrate, forage, and feces. Six procedures were evaluated: ratio of nitric to perchloric acid at 2:1, 3:1, and 4:1 v/v in a one- or two-step digestion. There were no direct or interaction effects (p>0.01) of nitric to perchloric acid ratio or number of digestion steps on magnesium and zinc contents. Calcium and phosphorus contents presented a significant (p<0.01) interaction between sample type and nitric to perchloric acid ratio. Digestion solution of 2:1 v/v provided greater (p<0.01) recovery of calcium and phosphorus from bone samples than 3:1 and 4:1 v/v ratio. Different acid ratios did not affect (p>0.01) calcium or phosphorus contents in carcass, excreta, concentrate, forage, and feces. Number of digestion steps did not affect mineral content (p>0.01). Estimated concentration of calcium, phosphorus, magnesium, and zinc in carcass, excreta, concentrated, forage, and feces samples can be performed using digestion solution of nitric to perchloric acid 4:1 v/v in a one-step digestion. However, samples of bones demand a stronger digestion solution to analyze the mineral contents, which is represented by an increased proportion of perchloric acid, being recommended a digestion solution of nitric to perchloric acid 2:1 v/v in a one-step digestion.

• 대한약침학회지
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• 제10권2호통권23호
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• pp.25-30
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• 2007

Objectives : Free radical metabolism seems to occupy a remarkably common position in the mechanisms of aging and aging related disease. Oxidative damage to DNA, lipids. proteins and other molecules may contribute to the development of cancer, cardiovascular disease and possibly neurodegenerative disease. This study was designed to find out whether Carthami Flos Herbal-Acupuncture Solution can scavenge Nitric Oxide(NO) or not. SNAP is NO generator. NO concentration was estimated after 2,6, 12 and 24 hrs in no treatment group, after treatment with Vit. C or 1, 10, 100${\mu}$g/m1 of Carthami Flos Herbal-Acupuncture Solution. There was no significant scavenging effect of Carthami Flos Herbal-Acupuncture Solutionon NO after 2 hrs. But there was a significant scavenging effect of Cafhami Flos Herbal-Acupuncture Solution on NO in 10${\mu}$/m1 group after 6hrs. And there was a significant scavenging effect of carthami Flos Herbal-Acupuncture Solution on NO in 1, 10${\mu}$g/ml group after 12, 24 hrs. These results suggest that Carhami Flos Herbal-Acupuncture Solution has scavenging effect on NO. This study shows that Carthami Flos Herbal-Acupuncture Solution can be used for aging related disease and further studies are required to investigate the antioxidative effects of it.

• 자원리싸이클링
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• 제18권5호
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• pp.44-51
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• 2009

전자스크랩중에 함유된 구리 및 주석을 습식공정으로 회수하기 위하여 기초 연구를 실시하였다. 침출제로 질산을 이용하여 분쇄된 전자스크랩에서 구리, 주석, 납, 철 등의 금속 성분들에 대한 침출율을 조사하고 최적 침출조건을 제시 하였다. 이러한 질산 침출 용액으로부터 TBP를 이용하여 유리질산을 분리 추출하여 재활용하기 위한 기초 연구를 실시하였다. 실험 결과 3.0-4.0 M 질산으로 구리를 효과적으로 침출시킬 수 있었으며, 질산 침출액 중 유리질산을 60% TBP에 의해 95%정도 추출이 가능하였고, 유기상에 추출된 질산의 98%를 증류수에 의해 탈거하여 질산침출액으로 재사용이 가능하였다.

• 한방안이비인후피부과학회지
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• 제32권3호
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• pp.13-22
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• 2019

Objectives : Armeniacae semen is the seed of Prunus armenica L. var. ansu MAXIM, and this is classified into Rosaceae. Armeniacae semen has been used for centuries in traditional oriental medicine for the treatment of pain and inflammatory diseases. Amygdalin is the major compound of Armeniacae semen, and it is now being used for the treatment of pain and cancer. Methods : In the present study, we compared the effects of an aqueous extract of Armeniacae semen and a solution of amygdalin extracted from Armeniacae semen on lipopolysaccharide(LPS)-stimulated prostaglandin E2 synthesis and nitric oxide production in mouse BV-2 microglial cells. For this study, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay, reverse transcription-polymerase chain reaction(RT-PCR), prostaglandin E2 immunoassay and nitric oxide detection were performed on mouse BV-2 microglial cells. Results : In the present study, an aqueous extract of Armeniacae semen and an amygdalin solution extracted from Armeniacae semen suppressed prostaglandin E2 synthesis and nitric oxide production by inhibiting the LPS-induced enhancement of cyclooxygenase-2(COX-2) mRNA and the inducible nitric oxide synthase mRNA in mouse BV-2 cells. For the cyclooxygenase-1(COX-1) expression, an aqueous extract of Armeniacae semen showed a more potent suppression effect compared to the amygdalin solution. However, the amygdalin solution more potently suppressed the LPS-induced COX-2 mRNA expression compared to the aqueous extract of Armeniacae semen. Conclusions : As a result, aqueous extract of Armeniacae semen and amygdalin exert anti-inflammatory and analgesic effects.

• Carbon letters
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• 제9권1호
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• pp.8-16
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• 2008

Oxidized activated carbons were prepared by reacting steam-activated carbon developed from pecan shells with nitric acid of varying strength (15, 30, 45 and 60%). The textural properties and the chemistry of the surface of the non-oxidized and of the oxidized carbons were determined from nitrogen adsorption and base neutralization capacities. The uptake of Pb(II) and Cd(II) from aqueous solution by these carbons was determined by kinetic and equilibrium experiments as well as by the column method. Treatment with nitric acid brought about drastic decrease in surface area and remarkable increase in the pore size of the carbon with these changes depending on the strength of nitric acid. Nitric acid increased the surface acidity by developing new surface oxygen functional groups of acidic nature. $HNO_3$-oxidized carbons exhibited high adsorption capacities for Pb(II) and Cd(II). The adsorption of these ions increased with the decrease of the surface pH of the carbon and with the increase of the solution pH from 2.5 to 6 and 7. The amount adsorbed from lead and cadmium was also related to the amount of surface acidity, the pH of the point of zero charge and on some metal ion parameters. Cadmium and lead uptake by the investigated carbons followed pseudo-second order model and the equilibrium sorption data fitted Langmuir adsorption model.

• 자원리싸이클링
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• 제26권1호
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• pp.51-58
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• 2017

TBP(tributyl phosphate)를 사용하여 왕수 침출액으로부터 질산과 금을 추출하여 회수하는 공정을 개발하기 위한 기초연구가 수행되었다. 순수한 왕수용액으로부터 추출제의 농도, 질산과 염산의 농도 비에 따른 질산의 추출거동을 조사하였으며, 금을 함유하는 왕수용액으로부터 질산과 금의 추출율을 구하였다. McCabe-Thiele 도로부터 얻어진 조업단수와 상비로 역류추출을 행하여 이론적인 추출단수를 검증하였다. 유기상에 장진된 질산과 금의 연속적인 회수를 위한 탈거실험을 수행하였다. 질산과 금의 추출과 염산의 영향을 고려하여 O/A = 1:0.85의 조건으로 역류추출을 통해 2단에 의해 $103.0mg{\cdot}L^{-1}$의 금은 99.9% 추출되었으며, 3단에 의해 $151.2g{\cdot}L^{-1}$의 질산은 98.0% 추출되었다. 질산과 금의 탈거제로는 증류수와 티오황산나트륨이 사용되었으며 탈거율은 각각 99.5%, 92.0%이었다. 이와 같은 연구결과로 왕수용액에 함유되어 있던 금과 질산을 동시에 추출하고 연속적인 탈거공정에 의해서 질산과 금을 회수하는 것이 가능함을 확인하였다.