• 약학회지
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• 제37권2호
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• pp.119-123
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• 1993

A spectrophotomertic method is proposed for the determination of antihistamines. The method is based on solvent extraction of the ion pair formed between antihistamines and colored picric acid into chloroform. The binding state of antihistamines-picric acid complexes were presumed by IR and $^{1}$H-NMR spectra as intermolecular hydrogen bonding. This method was applicable to the determination of antihistamines in the pharamaceutical preparations.

• 분석과학
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• 제16권4호
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• pp.261-268
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• 2003

불활성기체용해-열전도도검출법에 의한 수소분석시 매질효과를 조사하기 위해 티타늄 및 지르코늄-2.5니오븀 매질의 수소 표준물질 및 수소기체 주입에 의한 교정계수를 측정하였다. 또한 주석 조연제를 사용하지 않고 티타늄 및 지르코늄-2.5니오븀 매질 수소 표준물질의 수소 추출효율을 조사하였다. 수소기체 주입에 의한 수소분석기의 보정에 대해 지르코늄-2.5니오븀 매질 수소표준물질의 그것은 2~3% 높았으며, 티타늄 매질의 수소 표준물질은 약 14% 높은 값을 주었다. 교정계수 측정결과에 의하면 티타늄 매질 시료의 수소추출 효율이 지르코늄-2.5니오븀 매질 시료에 비해 약 12% 낮을 것으로 예상된다. 주석을 사용하지 않았을 때 티타늄 및 지르코늄-2.5니오븀매질 수소 표준물질의 수소 회수율은 약 70% 이었으며, 티타늄의 수소 회수율이 지르코늄-2.5니오븀 보다 낮았다.

• 한국수소및신에너지학회논문집
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• 제24권1호
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• pp.44-49
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• 2013

Hydrogen penetration into a metal leads to damages and mechanical degradations and its content measurement is of importance. For a precise measurement, a sample preparation procedure must be optimized through a series of studies on sample washing and drying. In this study, two-step washing with organic solvents and thermal soaking in inert gas were tried with a rod-shaped, API X65 steel sample. The samples were machined from a steel plate and then washed in acetone and etyl-alcohol for 5 minute each and dried with compressed air. After then, the samples were thermally soaked in a home-made nitrogen gas chamber during 10 minute at different heat gun temperatures from 100 to $400^{\circ}C$ and corresponding temperature range in the soaking chamber was from 77 to $266^{\circ}C$ according to the temperature calibration. Hydrogen residue in the samples was measured with a hot extraction system after each soaking step; hydrogen residue of $0.70{\pm}0.12$ wppm after the thermal soaking at $77^{\circ}C$ decayed with increase of the soaking temperature. By adopting the heat transfer model, decay behavior of the hydrogen residue was fitted into an exponential decay function of the soaking temperature. Saturated value or lower bound of the hydrogen residue was 0.36 wppm and chamber temperature required to lower the hydrogen residue about 95% of the lower bound was $360^{\circ}C$. Furthermore, a thermal desorption spectroscopy was done for the fully soaked samples at $360^{\circ}C$. Weak hydrogen peak was observed for whole temperature range and it means that hydrogen-related contaminants of the sample surface are steadily removed by heating. In addition, a broad peak found around $400^{\circ}C$ means that parts of the hydrogen residue are irreversibly trapped in the steel microstructure.

• 한국안전학회지
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• 제8권2호
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• pp.44-50
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• 1993

The objective of this study was to investigate the extraction of chromium(Vl) ion in waste water through the liquid surfactant membrane with open-type Perforated Reciprocating-Plate Column. Extraction experiments were conducted to measure the effect of flow characteristics of continuous and dispersed phase and stroke velocity, sodium hydroxide concentraction in internal aqueous phase, sulfuric acid concentraction in outer phase, and residence time distribution and measured extraction velocity. The result of experiments showed that extraction velocity of chromium ion was maximum when stroke velocity was 180 1/min and dispersion phase velocity was 30m11min, continuous phase velocity was 20m1/min. Extraction velocity of chromium ion increased with increasing difference of hydrogen ion concentraction of dispersion and continuous phase and column stage decreased.

• 신재생에너지
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• 제10권1호
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• pp.30-40
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• 2014

The main object of this study was to offer information about incoming waste in landfill and to evaluate biochemical methane and hydrogen sulfide potentials of landfill wastes. We examined brick, soil, mixed waste (C&D waste and MSW) samples for the study. The leaching experiments showed that BOD, COD and sulfate were determined in the range of 0~18,816 mg/kg, 85~21,100 mg/kg and 160~1,205 mg/kg, respectively in 6hr extraction test. An accumulated extraction tests for 140day were determined BOD 226~197,219 mg/kg, COD 436~242,588 mg/kg and Sulfate 1,090~25,140 mg/kg. Also, BMP (biochemical methane potential) tests were carried out to examine methane and hydrogen sulfide yields for the 3 different wastes. As a result, methane yield was determined to 262.68 mL $CH_4/g$ VS of MSW and 0~17.75 mL $CH_4/g$ VS in brick, soil and C&D waste. Higher hydrogen sulfide yield was observed to 0.079mL $H_2S/g$ VS in C&D waste. This result indicate that brick and soil could be sources of sulfate, and higher production of hydrogen sulfide could be odor problem and inhibitor of methane production.

• 한국식품저장유통학회지
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• 제9권1호
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• pp.97-101
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• 2002

비파 부위별 추출물의 항균성과 항산화 활성을 조사한 결과는 다음과 같다. 과피 및 종자의 추출수율은 부탄을 분획물에서 각각 4.95%와 4.42%로 높게 나타난 반면, 잎, 씨를 제거한 과실과 과육은 물분획물에서 각각 5.10%, 23.60% 및 21.10%로 높게 나타났다. 항균활성은 잎과 씨를 제거한 과실의 경우 clear zone이 각각 Staphylococcus aureus에서 19 mm, 15mm, Escherichia coli에서 15 mm, 16 mm로 에칠 아세테이트 분획물에서 항균활성이 높게 나타났다. 비파의 메탄을 추출물을 극성과 비극성 용매로 순차별로 분획한 수소공여 능은 잎에서 82%, 씨를 제거한 과실 74%, 종자 68%, 과피 52% 및 과육 30%로 에칠 아세테이트 분획물에서 가장 높았다.

• Food Science and Biotechnology
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• 제27권6호
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• pp.1761-1769
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• 2018

Enzyme-assisted extraction is a cost-effective, safe, and efficient method to obtain bioactives from plant materials. During this study, 10 different marine algae from Sri Lanka were individually extracted by using five commercial food-grade carbohydrases. The enzymatic and water extracts of the seaweeds were analyzed for their antioxidant and anti-inflammatory activities. The highest DPPH, hydrogen peroxide ($H_2O_2$) and intracellular $H_2O_2$ scavenging abilities were observed from the Celluclast extract of Sargassum polycystum (CSp). CSp exerted protective effects against oxidative stress-induced cell death in hydrogen peroxide-induced Chang cells and in model zebrafish. The Celluclast extract of Chnoospora minima (CCm) showed the strongest anti-inflammatory activity against lipopolysaccharide (LPS)-induced NO production in RAW 264.7 macrophages ($IC_{50}=44.47{\mu}g/mL$) and in model zebrafish. CCm inhibited the levels of iNOS, COX-2, $PGE_2$, and TNF-${\alpha}$ in LPS stimulated RAW 264.7 macrophages. Hence, CSp and CCm could be utilized in developing functional ingredients for foods, and cosmeceuticals.

• 한국안전학회지
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• 제2권1호
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• pp.17-29
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• 1987

The extraction mechanism of Zinc from aqueous solution with D2EHPA (Di-2-Ethylhexyl Phosphoric Acid) dissolved in Kerosene was studied by the single drop method. The effect of the concentrations of reactant species on the extraction rate, Zinc and hydrogen ion in the continuous phase and D2EHPA in the dispersed, was studied for the drop rise period by the experiment. Then a theoretical analysis on the basis of Handlos-Baron modle was carried out. It becomes clear that the extraction rate was controlled by the neutral complex forming reaction at the drop surface from both analysises. From effect of the concentrations of species on the reaction rate, the extraction rate at the drop surface is considered to be as follows. $${\gamma}_{pn}=9.42{\times}10^{-7}\;\frac{[Zn^{2+}][(HR)_2]^{3/2}}{[H^+]^{3/2}}$$

• 한국식품과학회지
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• 제33권4호
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• pp.497-500
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• 2001

본 연구의 목적은 홍미삼의 기능성 연구의 일환으로 총 페놀성 화합물의 추출방법과 DPPH에 대한 수소공여능, linoleic acid의 산화방지활성 및 LDL에 의한 항산화활성 등을 중심으로 연구한 결과이다. 홍미삼에 60% 에탄올를 첨가하여 추출회수별 총 페놀성 화합물을 조사한 결과 3회까지 추출했을 때 대부분이 추출되었기 때문에 추출횟수는 3회가 적당한 것으로 판단되었다. 60% 에탄올 추출액의 수율은 3회까지 추출했을 때 약 37.35%가 추출되었다. 추출 용매에 따른 총 페놀성 화합물의 추출 효율은 물 추출구를 100%로 했을 때, 60% 에탄올 용액으로 추출한 뒤 농축하여 물로 부피를 재조정한 시험구는 122%로 조사되었다. 항산화활성 조사에서 DPPH에 대한 수소공여능에서 시간이 경과함에 따라 항산화 활성이 약간씩 증가하나 활성은 약한 편이었다. Linoliec acid 산화에 대한 산화억제 효과는 1,500 ppm 농도에서 약 72.23%의 저해율을 나타났으며, LDL에 대한 산화방지 효과는 250 ppm 농도에서 그 저해율이 약 22.52%로 나타났다.

• Journal of the Korean Wood Science and Technology
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• 제31권4호
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• pp.50-56
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• 2003

본 연구는 CCA 처리재로부터 방부제 유효성분을 추출하기 위한 적정 용제를 선정하고, 선정된 용제의 최적추출조건을 평가하기 위해 수행되었다. 추출수율과 용제의 사용 및 환경 안전성을 고려할 때, 과산화수소가 CCA 유효성분을 추출하는 데 가장 적절한 용제로 선정되었다. 과산화수소를 이용한 추출 결과, 추출온도, 추출용제 농도, 추출시간 간에 상호작용이 존재하였으나 추출온도와 추출용제의 농도가 높을수록, 그리고 추출시간이 연장될수록 CCA 유효성분의 추출수율은 증가되었다. 경제적인 측면을 고려할 때 가능하면 낮은 농도의 추출용제를 사용하여 저온에서 추출하여야 하나, 이 경우에는 필요한 추출수율을 달성하기 위한 추출시간이 상당히 길어지기 때문에 40℃ 이상의 온도에서 추출이 바람직하며 사용할 추출용제의 농도는 추출시간을 고려하여 최종적으로 결정하여야 된다고 사료된다.