• Applied Biological Chemistry
• /
• 제50권2호
• /
• pp.132-135
• /
• 2007

국내에서 새로 육성된 장미의 부가가치를 향상시키고 천연 식품소재로서 기능성을 탐색하는 기초연구의 일환으로 5개 장미 품종을 대상으로 유기용매 추출물을 제조하고 장미꽃 추출물이 CHO 세포의 생육에 미치는 영향을 MTT법으로 조사하였다. 장미 추출물들은 추출용매의 종류와 첨가농도에 따라 CHO 세포의 증식을 촉진하거나 생육을 억제하였으며 품종에 따른 차이는 없었다. Ether로 추출한 장미꽃 추출물을 5 ${\mu}$g/ml 농도로 첨가한 경우 대조군에 비하여 CHO 세포의 증식촉진효과가 가장 높았다. 이러한 결과는 장미꽃은 CHO 세포의 증식을 조절하는 생리활성을 나타내며, 신 기능성 식품소재로서 활용하는 가능성을 시사한다.

• Bulletin of the Korean Chemical Society
• /
• 제24권12호
• /
• pp.1775-1780
• /
• 2003

A continuous flow system has been developed to determine trace Cu(II), Mn(II), Ni(II) and Zn(II) in a large volume of water samples by a solvent sublation technique. The mixed solution of 1,10-phenanthroline(phen) and thiocyanate ion was used as ligands for the formation of their ternary complexes. The continuous system was constructed in this laboratory with a peristaltic pump, a mini shaker, three mixing bottles and a flotation cell by connecting each part with a polyethylene tube. The flotation conditions such as the flow rate of sample solution and the injection rates of ligand, buffer and surfactant solutions have been investigated to obtain the best sublation efficiencies. Each solution flowed into the flotation cell through each polyethylene tube by the peristaltic pumps. The ternary complexes were floated and extracted into MIBK in a flotation cell of 2 L by bubbling a nitrogen gas. The absorbances of extracted analytes in MIBK were directly measured by graphite furnace-AAS. The concentrations of 1,10-phenanthroline and thiocyanate ion were $2.6\;{\times}\;10^{-3}$ M and $2.3\;{\times}\;10^{-2}$ M in the mixed solution, respectively. The pH of sample solution was adjusted to 5.0 with a buffer solution and 1%(m/v) sodium lauryl sulphate solution was added as a surfactant to support the effective flotation of the complexes. The $N_2$ gas was bubbled at 30 mL/min for 90 minutes for 20 L of sample. Reproducible results of less than 10% RSD and recoveries of 80-120% could be obtained in real samples.

• 자원리싸이클링
• /
• 제11권6호
• /
• pp.12-17
• /
• 2002

$CuCl_2$-$NiCl_2$-$CoCl_2$용액으로부터 구리를 분리하기 위해 추출제로 Alamine336과 LIX84를 사용하여 추출실험을 하였다. 염산용액에서 Alamine336과 LIX84에 의한 구리, 코발트, 니켈의 분배계수와 구리의 분리계수는 금속이온과 염소이온간에 형성되는 착물의 농도에 큰 영향을 받았다. 염소이온농도가 0.5에서 4.0M사이인 용액에서 코발트로부터 구리의 분리성은 LIX84가 Alamine336보다 우수하였다. 염소이온농도가 1.0M인 용액에서 LIX84와 Alamine336의 부피백분율을 5에서 40%까지 변화시켜 추출한 결과 LIX84로 추출하는 경우 Alamine336에 비해 더 높은 구리의 분리계수를 얻었다.

• KEPCO Journal on Electric Power and Energy
• /
• 제2권1호
• /
• pp.103-108
• /
• 2016

Carbon Capture and Storage technologies are recognized as key solution to meet greenhouse gas emission standards to avoid climate change. Although MEA (monoethanolamine) is an effective amine solvent in $CO_2$ capture process, the application is limited by high energy consumption, i.e., reduction of 10% of efficiency of coal-fired power plants. Therefore the development of new solvent and improvement of $CO_2$ capture process are positively necessary. In this study, improvement of $CO_2$ capture process was investigated and applied to Test Bed for reducing energy consumption. Previously reported technologies were examined and prospective methods were determined by simulation. Among the prospective methods, four applicable methods were selected for applying to 0.1 MW Test Bed, such as change of packing material in absorption column, installing the Intercooling System to absorption column, installing Rich Amine Heater and remodeling of Amines Heat Exchanger. After the improvement construction of 0.1 MW Test Bed, the effects of each suggested method were evaluated by experimental results.

• Journal of Pharmaceutical Investigation
• /
• 제34권4호
• /
• pp.289-297
• /
• 2004

Acyclovir (ACV) is one of the most effective and selective agents against viruses of the herpes group. Because of low solubility, bioavailability of ACV has shown below 30% with oral dosage form. In our previous study, we reported that the fabrication of solid dispersion of ACV was possible and the solid dispersion of ACV and PVP was the most useful in all samples. In this study, we examined the effect of mixture ratio of polymers (PEG and PVP) to ACV. Solubility of ACV was dramatically increased up to 25 mg/ml in $80^{\circ}C$ distilled water. So water was used as a solvent to eliminate problem of residual solvent. Spray drying method was used for the solid dispersion of ACV as solvent extraction. Different scanning calorimeter was used to check degradation of drug. Polymer carriers were PEG 6,000 and PVP. In summary, ACV-PVP (1:3) showed the best solubility in distilled water.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제17권1호
• /
• pp.42-46
• /
• 2012

The ISO document of ISO/TC/190/SC3/WG11/N11 is a working draft of international standard (WD) dealing with analytical method for the determination of explosives and related compounds using high performance liquid chromatography. The scope of this WD covers the storage of samples, preparing test portion, extraction and instrumentation. The main purpose of this study was to improve the extraction conditions which were already adopted in the WD. For this purpose, mechanical shaking method could be corresponded up to 18 hours of ultrasonic bath extraction in the WD was tested. Methanol was also tested with the intention of being added as an extracting solvent other than acetonitrile in the WD. According to the results, 16 hours of mechanical shaking method showed statistically the same effectiveness as that of 18 hours of ultrasonic bath extraction. In case of extracting solvent, methanol also showed statistically the same extraction capability as acetonitrile for DNB, TNT, 2-A-DNT and 2,4-DNT. However, the recovery rate of TNB with methanol extraction was 40% higher than that of acetonitrile extraction. Through adding mechanical shaking method into committee draft (cf. the next stage draft of the WD during the process for making international standard), ISO standard of analyzing explosives and related compounds in soil would become more useful in dealing with huge number of field samples in the laboratory. In other aspect, adopting methanol as an alternative extracting solvent would be very effective in the terms of exchangeability with GC-ECD/MS method which is being developed by German experts.

• 보존과학회지
• /
• 제35권1호
• /
• pp.19-31
• /
• 2019

To study the cleaning effects and post-treatment stability assessment of various methods of cleaning textiles with metal thread, six naturally-soiled historical textiles with metal thread were investigated at the Metropolitan Museum of Art, New York. Prior to the cleaning of fabricated gold, silver, and copper thread that had been glued onto a paper substrate, the artificial deterioration was carried out in a controlled environment with light(UV and daylight), and temperature and humidity factors which would weaken and damage the samples. A synthetic soil mixture was applied to the samples to imitate soil found on the historic and archaeological textiles with metal thread; the cleaning effect and post-treatment assessment were investigated by use of three textile cleaning methods: mechanical cleaning, wet cleaning, and solvent cleaning. While investigating the naturally-soiled textiles with metal thread, it was determined that the soil colors and sizes of contaminating particles of each textile were different due to the diversity of original environmental factors and conditions. After cleaning with kneaded rubber, Stoddard solvent, n-decane or n-hexane, a bright, clean effect was apparent. Kneaded rubber was successful in picking up both large and small particles, but its stickiness caused some of the metal leaf to peel off. Stoddard solvent produced a good cleaning effect, but after use of n-hexane and n-decane in the cleaning process, a white layer of residue remained on the textile's surface. Wet cleaning was not effective and the rapid humidity changes between wet and dry conditions caused the edges of the paper substrate to lose their original shape.

• 약학회지
• /
• 제42권6호
• /
• pp.621-626
• /
• 1998

Cactus (Opuntia ficus-indica var saboten Makino) is a tropical or subtropical plant, which is widely used as folk medicine for burned wound, edema and indigestion. We previously found that the ethanol extract of cactus stem showed anti-inflanunatory action. This investigation was designed to isolate the active fraction of anti-inflanimatory action from cactus stem by solvent extraction and colunm chromatography. Carrageenan-induced paw edema in rats and acetic acid-induced writhing test in mice were used as animal models to search anti-inflammatory and analgesic activities. respectively. The ethanol extract of cactus stem was consecutively extracted with hexane, ethyl acetate, and n-butanol. The hexane fraction was the most effective in carrageenan-induced paw edema, and then was separated in colunm chromatography of silica gel by the elution with hexane/ethyl acetate mixture. The most effective fraction 1 was separated in a second colunm chromatography by eluting with hexane/diethyl ether mixture. The most effective fraction 1-5 was obtained, and separated in a third column chromatography by eluting with hexane/chloroform mixture. It produced the most effective fraction 1-5-1. Moreover, fraction 1-5-1 showed an inhibitory effect on acetic acid-induced writhing in the doses of 30mg/kg and 60mg/kg,p.o.,indicating that it also contained analgesic activity.

• Food Science and Biotechnology
• /
• 제17권3호
• /
• pp.508-513
• /
• 2008

Erythromycin has been used to treat Streptococosis, Edwardsiel1osis, Vibriosis, Bacterial enteritis in the cultured fish. In this study, a rapid and effective erythromycin analysis method with new sample treatment protocol and liquid chromatography/tandem mass spectrometry (LC/MS/MS) system for fish products was developed. For the erythromycin extraction from fish muscle, the solvent mixture composed of 0.2% meta-phosphoric acid and methanol (6:4) showed good recovery rate, and the optimum extraction solvent volume was 20 mL. Erythromycin detection using LC/MS/MS were carried out under electro spray ionization (ESI) positive condition and erythromycin mass value 576.2 and 157.9. And the detection limit of the established method was 0.005 mg/kg in fish products. The recovery rate of the developed method applied to the fish species were as following, olive flounder, $87.6{\pm}5.0%$; black rockfish, $87.2{\pm}6.4%$; eel, $85.2{\pm}4.8%$; and rainbow trout, $86.0{\pm}6.2%$. In the established method in this study, the correlation of coefficient values ($R^2$) of erythromycin calibration curve (n=11) was 0.9998.

• Bulletin of the Korean Chemical Society
• /
• 제32권5호
• /
• pp.1564-1568
• /
• 2011

A solvent extraction separation, preconcentration and determination of thorium with a new crown, 2-ethyl-N-benzyl-4,7,10,13,16-pentaoxa-1-azacyclooctadecane (MACE), is described in the study. The amount of thorium in the aqueous phase and organic phase was determined by Inductively Coupled Plasma-Optical Emission Spectroscopy and Ultraviolet-Visible, respectively. Thorium loaded organic phase was quantitatively stripped in a stage by using 1.0 M $HNO_3$. Thorium was effectively extracted with MACE in the pH range of 6-7 to produce a 3:2 complex ratio in the chloroform. A highly sensitive and rapid spectrophotometric method was described for determination of trace amounts of thorium with MACE. The effective molar absorption coefficient at 281 nm is $1.98{\times}10^3\;mol^{-1}cm^{-1}$, and the system complies with Beer's law in the range from 0.464 to 2.32 ${\mu}gm\;L^{-1}$ of thorium. Thorium was also determined in standard and environmental samples.