• Resources Recycling
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• v.21 no.6
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• pp.3-11
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• 2012

Some methods used for the recovery of osmium and ruthenium from primary/secondary sources are reviewed. Both Ru and Os could form volatile oxides which enable their separation from the other PGMs by distillation as a traditional method. In hydrochloric acid solution, they also form chloro-complexes with different valence states. Amines or amine based mixture have been used to extract Ru. Solvating extractants are employed to separate Ru and Os. The detailed extraction and stripping conditions of several solvent extraction processes have been reviewed. As an alternative to solvent extraction, solid-liquid method can be applied to recover trace amount of these metals.

• Resources Recycling
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• v.4 no.3
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• pp.2-9
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• 1995

The rccoverg and separation pracess of nikcl, vanadium and molybdenum from spent dcsulfilrizing catalyst ofpetrochemical rndustries was studied. Tnis process was canied out wet process which is consist of roasting, ammonialeaching and solve111 exDaction techniqcs. The metal ions of NI, V and Mo as vduable compollents were treated byroasting them a1 low lernperatuc, 400$^{\circ}$C in first dep, and then dlssah'ed nu1 at 80$^{\circ}$C wlth ammonium cabonate mlulion.Aftcr cooling them a1 room tempertaure, vanadium wa rccavered from mathcr iiquur in thc f n m of precipitate, sodiumvanadales The Secand slep, roasting the catalyst which is added sodium carbonate ul IOOO"C, was employed. Leachingwith distilled ~ a l e rga ve a iwo phase resultant, solutio~c~a ntaning Ni, V and Mo and solid residue containing sibca,alurmniu~n and iron. A solvcnt exlclction technique uslng vvriuus extractanls, MSP-8, TOIUC, LIX64Pi was eflecnve farthc extraclion and scparation ol thrcc mcfals from thc ammonical 11qou1 thc ammonical 11qou1.

• Resources Recycling
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• v.25 no.5
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• pp.50-56
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• 2016

Extraction behaviour of silver from nitric acid solutions by Cyanex 301 as an extractant was examined. Detailed studies have been conducted to evaluate the effect of different variables influencing the extraction such as concentration of nitric acid and extractant, phase ratio(O/A) and synergism of mixed extractant. The extraction behaviour of associated metals namely Ca, Al, Fe, Zn and Sr has been investigated. The extraction results show that Ag can be extracted effectively by Cyanex 301 and selectively extracted from 3.0M $HNO_3$ using 5% Cyanex 301. Impurity metals loaded in organic phase can be effective scrubbed by 4.0M HCl. Finally, pure silver solution can be obtained efficiently by thiourea as a stripping reagent.

• Journal of Life Science
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• v.26 no.8
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• pp.921-927
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• 2016

Postprandial hyperglycemia is an early defect of type 2 diabetes and one of primary anti-diabetic targets. The alpha-glucosidase inhibitors regulate postprandial hyperglycemia by impeding the rate of carbohydrate (such as starch) digestion in the small intestine. This study was designed to investigate the inhibitory actions of mulberry fruit extract (MFE) on α-glucosidase and α-amylase activities, and its alleviating effect on postprandial hyperglycemia activities in vitro and in vivo. Male four-week old ICR mice and streptozotocin (STZ)-induced diabetic mice were treated with mulberry fruit extract. MFE showed strong inhibitory effects against α-glucosidase and α-amylase activities, with half-maximal inhibitory concentration (IC₅₀) values of 0.16 and 0.14 mg/ml, respectively, and was more effective than acarbose, which was used as a positive control. The increase in postprandial blood glucose levels was more significantly attenuated in the MFE-administered group mice than in the control group mice of both STZ-induced diabetic and normal mice. Moreover, the area under the glucose response curve significantly decreased following MFE administration in diabetic mice. These results indicate that MFE may be a potent inhibitor of α-glucosidase and α-amylase, and helpful in suppressing postprandial hyperglycemia in diabetic mice. The mulberry fruit extracts may be considered as a potential candidate for the management of diabetes.

• The Journal of Korean Medicine
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• v.22 no.2
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• pp.53-63
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• 2001

This study was carried out to investigate the physiological activityof the water extract from EA. The present study was done to investigate the effects of EA on cultured hepatocyte cell system and lipid peroxidation in $A{\beta}$ treatment conditions. Pretreatment of EA attenuated in cell cytotoxicity enhanced by increasing concentrations of $A{\beta}$. MDA level induced by $A{\beta}$ treatment was significantly increased and the level was slightly reduced by pretreatment of EA. The ability of EA to reduce cell death and MDA level induced by $A{\beta}$ suggest that EA may be a protective agent against free radical generating compounds such as $A{\beta}$. EA exhibited anti oxidative activity at all concentration tested.The extract was as good as antioxidative activity of the synthetic antioxidants, butylated hydroxy toluene and ascorbic acid. Furthermore, this was superior to that of natural antioxidant, a-tocopherol. In the presence of heavy metal ions ($Fe^{2+},{\;}Zn^{2+}$), EA showed strong antioxidative activity. The extracts showed about 3075% in the nitrite scavenging effect under pH 1.2 and $37^{\circ}C$ for 1 hr. There was significant difference among concentration of extracts.

• Applied Chemistry for Engineering
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• v.7 no.1
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• pp.153-161
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• 1996

Several main nuclides($^{241}Am$, $^{152}Eu$ and $^{237}Np$) in radioactive waste solution were selected and examined to mutual separation with di-(2-ethylhexyl) phosphoric acid by solvent extraction technique. $^{237}Np$ was extracted more than 99.9% adding the $H_2O_2$ that was a good reductant for the oxidation state control of $^{237}Np$. $^{241}Am$, $^{152}Eu$ and $^{237}Np$ could be fairly well separated one another during the different sequence stripping stages, but about 7~9.6% of the other nuclides were still remained for the $^{241}Am$ stripping solution. This result shows that the product of $^{152}Eu$ and $^{237}Np$ was good, but $^{241}Am$ may be needed to further purification process. It was also discussed on the cause of the third phase formation phenomenon that was found in the solvent regeneration.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2001.11a
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• pp.64-68
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• 2001

본 연구에서는 (1) 인테리어에 대한 감성어휘모형을 도출하고, (2) 거실 인테리어의 주요 배색을 추출한 후, (3) 거실 공간의 배색 감성모형을 개발하였으며, (4) 연구결과를 토대로 거실 인테리어 디자인을 위한 배색기법을 제시하였다. 이를 위하여 인테리어를 기술하는 감성어휘를 수집하고 이들로부터 대표적 감성어휘를 추출, 감성어휘척도를 구성하였다. 감성조사분석을 통해 '따뜻하다-차갑다'(제 1차원), '고급스럽다-소박하다(제 2차원)', '현대적이다-고전적이다'(제3차원)의 세 차원축이 도출되었고, 이렇게 도출된 감성공간 상에 감성어휘들을 대응시키고, 9개의 감성 범주로 구분함으로써 감성어휘모형을 개발하였다. 한편, 거실 인테리어의 주요 배색을 추출하여 배색자극물을 개발하고, 감성어휘모형과의 관계분석을 통해 거실 공간의 배색 감성모형을 개발하였다. 최종적으로, 배색 감성모형에서 도출된 9개의 감성범주와 그에 대응하는 배색을 기반으로 하여 거실용 인테리어 디자인의 핵심이미지에 따른 배색지침을 제시하였다.

• Journal of Gastric Cancer
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• v.8 no.3
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• pp.120-128
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• 2008

Purpose: Mistletoe extract was widely used for cancer treatment as complementary or alternative therapy in European area from early twenty century. It is currently used as alternative anti-cancer remedy by piecemeal in domestic medical group, however, the anti-cancer mechanism of mistletoe extract was not known precisely until now. In this study the effect of mistletoe extract on gastric cancer was studied vis cell line experiments. Materials and Methods: The SNU719 gastric cancer cell line was used, and ABNOBAviscum-Q and ABNOBAviscum-F were treated to cells as mistletoe extract, or 5-FU and cisplatin were used with mistletoe extract. The cell viability and cell death rate were estimated by CCK-8 assay kit and lactate dehydrogenase (LDH) assay kit in each. Caspase 3 assay kit was used to measure caspase 3 activity. The protein expression amounts of Bcl2, p53, and PTEN were estimated through Western blot analysis. Results: The co-treatments of mistletoe extract Q/F and 5-FU/cisplatin decreased lesser cell viability than only mistletoe treat. Caspase 3 activity was increased 4~6 times in co-treatment of mistletoe extracts and 5-FU than control. Bcl2 protein expression was reduced by mistletoe extracts or anti-cancer drugs, further more, the co-treatment of mistletoe extracts and 5-FU/cisplatin diminished more the expression than only mistletoe treatment. Mistletoe extracts did not affect the protein expressions of p53 and PTEN. Conclusion: It was concluded that the anti-cancer mechanism of mistletoe extracts was made by caspase 3 activation and lowered Bcl2 expression, and this apoptosis inducing mechanism was independent to p53.

• Applied Chemistry for Engineering
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• v.21 no.5
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• pp.509-513
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• 2010

Recently, an amount of waste electronic devices such as LED and trichromatic fluorescent lamp has increased with the development of electronic industry. Reportedly, rare earth metals such as yttrium and europium have been discovered in the waste electronic devices. In order to improve the selectivity of yttrium and europium, the effects of the following factors on recovery experiment have been considered : i) fatty acids with various alkyl chain lengths, ii) the concentration of extractant, and iii) pH. The results show that the extraction efficiencies decrease at the same pH with decreasing the concentration of extractant and so $pH_{0.5}$ (That value of pH in an aqueous phase at which the distribution ratio is unity at equilibrium: 50% of the solute is extracted (E = 0.5) only when the phase ratio is unity.) moves into higher pH. The highest selectivity of yttrium and europium was obtained with tetradecanoic acid as extractant. The extraction mechanism of yttrium and europium was varied with the change of concentration of the tetradecanoic acid. $MR_3$single-species was formed from the yttrium and europium ion in the extractant concentration less than 0.1 M. On the other hand, the yttrium or europium ion is solvated with three molecules of tetradecanoic acid monomer like $MR_3{\cdot}$ 3RH in the extractant concentration more than 0.1 M.

• Food Science and Preservation
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• v.30 no.2
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• pp.347-357
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• 2023

The succulent plant Aeonium sedifolium leaves contain several compounds that are of interest for their cosmetic uses on the skin. This study measured the inhibitory effects of enzyme production and antioxidant, astringent effects and skin wrinkles using Aeonium sedifolium leaves (ASL). The total phenolics compounds (TPC) content of ASL under optimal extraction conditions was 34.49 mg/g for hot water extract (ASLW) and 61.64 mg/g for 50% ethanol extract (ASLE). The ASLW and ASLE extracts were freeze-dried, powdered, and used as solids. TPC content, 2,2-diphenyl-1-picrylhydrazy (DPPH) radical scavenging activity, and 2,2'-azinobis (3-ethylben-zothiazoline 6-sulfonate) (ABTS) radical inhibition of the ASL phenolics were tested. The DPPH radical scavenging activities of ASLW and ASLE were tested at a TPC of 100 ㎍/mL. ABTS radical inhibition showed antioxidant activity of 100.00% in ASLW and ASLE, and the antioxidant protection factor of ASLW and ASLE was 1.07 and 1.22, respectively. The thiobarbituric acid-reactive substance (TBARS) inhibitory activity of ASLW and ASLE was 77.00%. The elastase inhibitory activity of ASLE was 69.03%, and collagenase inhibition activity for ASLW and ASLE was 29.82% and 54.76%, respectively. The astringent effect of ASLE was 89.82% at a TPC of 200 ㎍/mL. Thus, we concluded that ASL has the potential as a functional cosmetic ingredient with anti-aging effects on the skin.