• Archives of Pharmacal Research
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• 제17권5호
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• pp.360-363
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• 1994

Column--swtiching technique with a reversed-phase high performance liquid chromatographic method has been developed for the routine analysis of radioiodinated insulin and its degadation products in biological fluids. The diluted biological samples were loaded onto a precolumn packed with LiChrosorb RP-8 $(25-40{\;}{\mu}m)$ using 0.1% trifuoroacetic acid (TFA) in water as a washing solvent. After valve switching, the concentrated insulins were eluted in the back-flush mode and separated by a W-Porex $C_{18}$ column with a gradient of 0.1% TFA in water and 0.1% TFA in acetonitrile as the mobile phase. The method showed good precision, accuracy and speed with the detection limit of 20 pg/ml. Total analysis time per sample was about 40 min and the coefficients of variation were less than 8, 2%.

• 한국염색가공학회지
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• 제10권4호
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• pp.7-14
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• 1998

Microwaves are high frequency radiation capable of generating very rapid, uniform and efficient heating of textile material. Microwave heated dyeing of polyester fabric was tried with different solvent systems, irradiation time and dye concentration. Microwave fixation methods were used with 100% water,30% urea, EG and DMF, respectively, pad-baths in which the padded fabrics were exposed over a heated or boiling water bath to maintain sufficient moisture content during irradiation. In order to ascertain the relation between the dyeing property of polyester fabric and the microwave irradiation condition caused by microwave heating, the K/S values and fastness properties of dyed fabrics such as light, washing and sublimation fastness were measured.

• 복식
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• 제47권
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• pp.89-100
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• 1999

This study was carried to a textile conservation process included washing effect fiber analysis such as fiber identification fabric density and thickness color fading and of extracted soils. the following results were obtained. 1. AS a result of investigating to fabric surfaces by S.E.M all of cleaning methods wet cleaning-solvent cleaning in charge system were effective to remove soils from fabrics. 2. The buried fabrics were made of silk few of them were cotton ramie and hemp. 3. According to fabric density and thickness used fabrics were almost medium weight fabrics. 4. Low values of L, a, b indicated that the colors of these fabrics were faded to yellow and brown. 5. The soil components were hydrocarbon-alkane group alkyl alcohol and ketone group.

• 한국미생물·생명공학회지
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• 제27권2호
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• pp.159-165
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• 1999

Pseudomonas aeruginosa JRT-4 strain was used as a biosurfactant-producing microorganism in this study. It was one of the microorganisms isolated from the sewage sludge, the main and branch streams of Han river. The surface tension of the culture broth of P. aeruginosa JRT-4 decreased to 30mN/m. The crude biosurfactant was obtained from the culture broth by acid precipitation, solvent extraction, evaporation, and freeze drying. The CMC value of the crude biosurfactant was 0.006%(w/v). From analysis of the chemical structure of biosurfactant, it was determined as rhamnolipid 1 and 3 structures by FAB mass spectrometer. In the washing test for artificially contaminated textiles, the biosurfactant showed better bleachness than the two chemically synthesized surfactant, LAS and SLES. Finally, the biodegradation and ecotoxidolorical tests showed that the biosurfactant was readily biodegradable in the environment and a mild material for microorganisms and green algae.

• Bulletin of the Korean Chemical Society
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• 제35권1호
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• pp.173-176
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• 2014

The hollow $SiO_2$ spheres with uniform size were synthesized by a modified Stober method under the control of polyelectrolytes (PSS and PAA) as templates. This synthetic route includes the formation of spherical colloid micelle in ethanol solution, hydrolysis of TEOS under control of ammonia, and the removal of polyelectrolyte by washing or calcination. Hollow silica spheres with controllable core diameters between 100 and 270 nm and wall thickness between 15 and 50 nm have been synthesized. The influence of template solution concentration and solvent and dispersant on the formation of silica hollow spheres is studied and reported in detail.

• 한국안전학회지
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• 제11권4호
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• pp.79-83
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• 1996

In this study, in attempt to develop a new application technique of discharge plasma, we employed a kind of discharging method called SPCP ( short for Surface discharge induced Plasma Chemical Process). Applications of SPCP have been widely used for years. Compact ozonizers to deodorize household equipments like refrigerators we a part of such applications. We took advantages of the compactness and durability of the SPCP electrode to set up an experimental apparatus for decompositing vapor of aromatic hydrocarbons such as toluene, benzene and xylenes, which are major substances given off In painting or washing processes and aggravate working conditions. Results obtained from this study are summarized as follows. 1) Aromatic hydrocarbon vapors of up to 2,000ppm were almost thoroughly decomposed at the flow rate of 4ℓ/min or lower under the discharge with electric power of 400 Watts. 2) In dry air, as the decomposition progresses, tar-like substance deposits on the discharging areas, which deteriorated the decomposition rate in the end. This substance, however, was almost thoroughly removed by keeping discharge in dry air containing no solvent vapor.

• Korean Chemical Engineering Research
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• 제61권4호
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• pp.570-575
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• 2023

Targeted anticancer drug delivery systems are needed to enhance therapeutic efficacy by selectively delivering drugs to tumor cells while minimizing off-target effects, improving treatment outcomes and reducing toxicity. In this study, a silica-based nanocarrier capable of targeting drug delivery to cancer cells was developed. First, silica nanoparticles were synthesized by the Stöber method using the surfactant cetyltrimethylammonium bromide (CTAB). Increasing the ratio of EtOH in the solvent produced uniformly spherical silica nanoparticles. Washing the nanoparticles removed unreacted residues, resulting in a non-toxic carrier for drug delivery in cells. Upon surface modification, the pH-responsive polymer, polyethyleneimine (PEI) exhibited slow doxorubicin release at pH 7.4 and accelerated release at pH 5.5. By exploiting this feature, we developed a system capable of targeted drug release in the acidic tumor microenvironment.

• 자원리싸이클링
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• 제20권3호
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• pp.48-54
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• 2011

황산으로 탈황 폐촉매를 침출한 결과 황산농도 1 M, 반응시간 1 hr인 실험조건에서 Ni 및 V은 95% 이상, 그리고 Mo은 30%가 침출되었다. 탈황 폐촉매의 Mo matrix 특성으로 인하여 다른 금속에 비하여 Mo의 침출율이 낮았으며, 본 침출반응은 확산반응에 의하여 제어되는 것으로 판단된다. Mo을 완전히 침출하기 위하여 유황성분이 제거된 폐촉매로 침출실험을 실시하였다. 1M 황산으로 처리후 탄산나트륨으로 세척시 Ni, Mo 그리고 V의 침출율은 99% 이었다. Ni 2 g/L; V 9 g/L, Mo 0.6 g/L 조성의 침출액을 LIX 841로 용매추출한 조건에서 A:O 비 5:2, 2단계로 처리시 Mo은 98% 이상 추출되었으며 A:O 비 5:3, 2단계로 처리시 V은 82%가 추출되었다.

• 한국의류산업학회지
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• 제15권1호
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• pp.138-146
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• 2013

Chemical compositions and biological functions of brown colorants extracted from pine bark(Pinus densiflora) have been studied. Dyeing test using multifiber fabrics with extracted colorants were preliminary carried out. Dyeing conditions and fastness tests of selected fabrics have been also studied. The brown colorants were produced 1.5% concentrations by solvent extraction from milled pine bark using methanol. The colorants were extracted with 80% methanol as best choice by a criteria of solid quantity and dyeability on fabrics. The chemical compositions were identified as mixtures of taxifolin epicatechin and procyanidin by LC/MS analysis. The brown colorants could be dyed not only natural fibers such as cotton, silk and wool but also synthetic fiber as nylon and semi-synthetic fiber as viscose rayon. Maximum K/S values was shown at 400 nm according to different fiber with color appearance of redish brown. Optimum pH and temperature of dyeing conditions was 4 and above $80^{\circ}C$, respectively. The brown colorants had a strong antioxidant activity compared to Butylated hydroxyanisole as standard and weak antimicrobial activity against E. coli. compared to kanamycin. Washing, rubbing, perspiration, dry cleaning and light fastness for cotton, nylon and silk dyed with the brown colorants were carried out by KS K method. Most of color fastness such as washing, rubbing, perspiration, and dry cleaning were represented as 4-5 grade. However, light fastness was reported as 2-3 grade. From this studies, brown colorants produced pine bark have a high potentials for natural dyeing on fabrics with antioxidant activity.

• 한국산업보건학회지
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• 제8권2호
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• pp.289-295
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• 1998

Used gasoline engine oils(UGEO) are carcinogenic in long term studies and capable of increasing the number of carcinogen-DNA adducts in short term studies when dermally applied to mice. The carcinogenic risk of UGEO has been attributed to the concentration of polycyclic aromatic hydrocarbons(PAH) which accumulate in the lubricating system during the combustion of gasoline. When dermally exposed to UGEO, the use of hand cleanser was commonly recommended for removing it. But generally workers who dermally exposed oils, use kerosene as cleaner which make skin trouble. During this study, female mice aged 4-6 weeks were utilized to evaluate the efficiency of kerosene, as solvent-based cleanser, following dermal exposure to UGEO. DNA adduct were detected at skin and lung tissues by using the $^{32}P$-postlabeling method. Washing with cleansers were done at two different interval times following dermal application of UGEO. The total DNA adducts in skin and lung tissues were statistically significantly increased in positive control groups, and of which the total adduct level in skin tissues was statistically significant higher than those in lung tissues(p=0.005). When washing kerosene, the DNA adduct level in skin tissues was statistically significantly decreased(p=0.0001). But DNA adducts in lung tissue was statistically increased(p=0.0039), and that washed at 8hr post exposure was more severly increase(p<0.05). The slope of regression between DNA adducts of lung between skin tissues was 1.0802. In conclusion, skin cleaning with kerosene facilitates passage of carcinogens to the lungs of animals dermally treated with used gasoline engine oils(UGEO).