• 대한화학회지
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• 제38권10호
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• pp.741-748
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• 1994

남조류의 독성물질인 microcystin을 HPLC로 분석하기 위해 지금까지는 ODS cartridge를 사용하였으나 본 연구에서는 CN cartridge를 사용하는 새로운 분석 방법을 시도하였다. CN cartridge는 0.5M 초산 용액으로 처리되었으며 Microcystins RR과 LR을 용리시키기 위해 30% Acetonitrile 용액이 사용되었다. CN cartridge를 이용하는 분석 방법이 기존의 ODS cartridge를 이용하는 방법보다 훨씬 더 정확한 정량을 할 수 있었다. 특히 Microcystin LR의 경우 피크 면적에서 현저한 차이를 보였다.

• 한국산업보건학회지
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• 제18권3호
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• pp.204-215
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• 2008

Many researches for service-life of chemical cartridges of respirators have been performed in many countries. On the result of these researches a few softwares programs were eventually developed to be used. In spite of that, it is difficult to apply these researches and softwares practically in the work spot because of too many factors that influence on service-life of chemical cartridges. This study was the first of two conducted for the purpose of developing program for estimating exchange period or service-life of chemical cartridges available feasibly in the workplaces. Collecting plan of cartridges discarded after use is in principle that three cartridges from three workers at a time, three steps of 1/2 exchange time due to smelling, just routine exchange time and 1.2 to 1.3 expanded time of routine exchange, total nine cartridges are collected in the same job site. 33 cartridges for organic vapor were collected in paint spray process of ship yard and paint factory, and 6 cartridges for acid were collected in plating process. These cartridges were analysed the remaining breakthrough time in 3M Innovation Center. Challenge vapor and breakthrough concentration were complied with Korean regulation for chemical cartridge respirators. Estimated breakthrough time was determined from previously used time plus breakthrough time for the remaining. Exchange period of cartridge would be the shortest time among three estimated breakthrough times. On the result breakthrough time for organic vapor was found to be relatively easily estimated, but that for acid aerosol or vapor was difficult to be confident. Even though this method was difficult to be precisely predicted exchange period of cartridge, it could be an alternative program practically available in the job site.

• 멤브레인
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• 제19권3호
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• pp.173-182
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• 2009

심층형여과 카트리지필터는 반도체 등 전자재료, 식음료, 각종 안료, 페인트, 잉크 등의 공정용 카트리지 필터로서 널리 사용되고 있는 필터이다. 이러한 공정용 카트리지 필터의 여과특성과 심층형여과 카트리지 필터의 종류, 제조업체 및 전세계 시장동향을 살펴보고, 심층형여과 카트리지 필터의 고장사례현황 및 원인규명과 함께, 신뢰성평가 방법에 대하여 고찰하였다.

• Bulletin of the Korean Chemical Society
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• 제32권1호
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• pp.71-76
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• 2011

An efficient nucleophilic [$^{18}F$]fluorination has been studied to reduce byproducts and preparation time. Instead of conventional aqueous solution of $K_2CO_3-K_{222}$, several organic solution containing inert organic salts were used to release [$^{18}F$]fluoride ion and anion bases captured in the polymer cartridge, concluding that methanol solution is the best choice. Comparing to azeotropic drying process, one min was sufficient to remove methanol completely, resulting in about 10% radioactivity saving by reducing drying time. The polymer cartridge, Chromafix$^{(R)}$ (PS-$HCO_3$) was pretreated with several anion bases to displace pre-loaded bicarbonate base. Phosphate bases showed better results than carbonate bases in terms of lower basicity. tert-Butanol solvent used as a reaction media played another critical role in nucleophilic [18F]fluorination by suppressing eliminated side product. Consequent [$^{18}F$]fluorination under the present condition afforded fast preparation of reaction solution and high radiochemical yields (98% radio-TLC, 84% RCY) with 94% of precursor remained.

• 한국산업보건학회지
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• 제19권2호
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• pp.102-112
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• 2009

The greatest concern of vapor/gas respirators is when to exchange chemical cartridges, but it is very difficult to estimate the breakthrough time of them in the workplace spot due to so many factors influencing on breakthrough. There needs to study on estimating cartridge exchange period available practically in the spot, even if it is not precise. In the previous study, authors suggested the method on estimating service-life of chemical cartridges using cartridges discarded after use. This followed study was to estimate exchange period for chemical cartridges using comparison of concentrations between Korean Occupational Exposure Limits (KOELs) and odor thresholds of chemicals. Chemicals were divided into four groups, I, II, III and IV groups. Group I chemicals are relatively safe if cartridges are just or slightly delayed exchanged when smelling since odor thresholds were less than 0.5 times KOELs. Odor threshold of Group II chemicals are 0.5~2.0 times KOELs and potentially hazardous if cartridges are exchanged when smelling. Those chemicals should be conducted program on estimating service-life of cartridges, which was just previously published (J Kor Soc Occup Environ Hyg 2008;18(3) 204-215). Group III chemicals (odor thresholds are more than 2.0 times KOELs) and Group IV chemicals (odorless or no data for smelling) must be performed the above mentioned program before cartridges. Even if this method on cartridge exchange using odor threshold is practically widely used in the workplace spot in the present, program on estimating service-life of cartridges is recommended for all chemicals to reduce potentially hazards.

• Korean Chemical Engineering Research
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• 제50권4호
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• pp.713-717
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• 2012

난백에 있는 40여 가지의 단백질의 기능적 특성에 대한 연구가 폭 넓게 진행되고 있지만, 그 특성이 모두 확인되지 않았다. 난백에서 순수하면서 변성되지 않은 단백질을 분리하는 방법을 연구하기 위해 본 연구에서는 난백 중 함량이 많은 lysozyme, ovotransferrin, ovalbumin을 분리했다. 난백에서 단백질을 다른 분리 방법보다 선택적으로 분리가 가능한 이온 교환 크로마토그래피를 이용했다. 그리고 분리된 단백질을 동정하기 위해서 Reversed-phase HPLC (RP-HPLC)를 사용했다. 이온 교환 크로마토그래피에서 HI Trap ion exchange cartridge (GE Healthcare, USA)를 사용했고, 그 중에서 양이온 교환 수지 SP (완충용액 pH 8.0, pH 5.2)와 음이온 교환 수지 Q (완충용액 pH 8.0)로 난백 단백질을 분리하였다. 분리한 난백 단백질들의 동정용 RP-HPLC에서는 C18 컬럼(Phenomenex, USA)을 사용했고 등용매 용리에서 이동상으로 acetonitrile (ACN)/distilled water (DW)/trifluoroacetic acid (TFA)의 부피비를 50/50/0.1로 사용했다. 이온 교환 크로마토그래피에 의해 각 단계에서 분리된 용출용액을 RP-HPLC으로 분석한 크로마토그램과 표준시료의 크로마토그램의 체류시간을 비교하여 난백에 포함된 ovotransferrin, ovalbumin, lysozyme이 순차적으로 용출됨을 알았다.

• Bulletin of the Korean Chemical Society
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• 제15권7호
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• pp.592-595
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• 1994

• Bulletin of the Korean Chemical Society
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• 제25권2호
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• pp.263-266
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• 2004

A sensitive, selective and rapid method has been developed for the determination ${\mu}$g/L level of vanadium ion based on the rapid reaction of vanadium(V) with 2-(2-quinolylazo)-5-diethylaminophenol (QADEAP) and the solid phase extraction of the colored chelate with $C_{18}$ cartridge. The QADEAP reacts with V(V) in the presence of citric acid-sodium hydroxide buffer solution (pH = 3.5) and cetyl trimethylammonium bromide (CTMAB) medium to form a violet chelate of a molar ratio 1 : 2 (V(V) to QADEAP). This chelate was enriched by solid phase extraction with $C_{18}$cartridge and the enrichment factor of 50 was obtained by elution of the chelates from the cartridge with ethanol. The molar absorptivity of the chelate is $1.28 {\times}10^5L\;mol^{-1}cm^{-1}$ at 590 nm in the measured solution. Beer's law is obeyed in the range of 0.01-0.6 ${\mu}$g/mL. The detection limit is 0.04 ${\mu}$g/L in the original samples. This method was applied to the determination of vanadium(V) in water and biological samples with good results.

• 한국안전학회지
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• 제19권4호
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• pp.74-79
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• 2004

[ $CO_3O_4/{\gamma}-Al_2O_3$ ] catalysts were reported high activity on the low temperature CO oxidation. The effects of the calcination temperature, the loaded amount of cobalt and the oxygen concentration on the characteristics of CO oxidation have been investigated for a emergency escape mask cartridge. $Co(NO_3)_2\cdot6H_2O$ was used as cobalt precursor and the catalysts were prepared by incipient wetness impregnation. TGA shows that enough calcination is accomplished at $450^{\circ}C$ and cobalt phase is $Co_3O_4$ after calcination in the temperature range of $300\ ~500^{\circ}C$. The specific surface area and pore volume of catalysts are decreased with increasing of loaded amount of cobalt. And with the increase of loaded amount of cobalt and the oxygen concentration, the catalytic activity is increased.

• Bulletin of the Korean Chemical Society
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• 제33권7호
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• pp.2177-2180
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• 2012

New [$^{18}F$]F-fluorination methods using a minimized amount of precursor has been developed by controlling the base concentration. In the first method, pre-conditioning of the anion exchange cartridge with $K_2CO_3$ solution or water was carried out. The trapped [$^{18}F$]fluoride on the cartridge was then eluted by KOMs or KOTf solution. [$^{18}F$]F-Fluorination could be performed without additional base. In the second method, the QMA cartridge was preconditioned with KOMs solutions. Trapped [$^{18}F$]fluoride on the QMA was then eluted with KOMs and additional base, such as KOH, $K_2CO_3$, and $KHCO_3$, was added into the reaction vessel. Method 1 showed a [$^{18}F$]F-incorporation yield of 20.9% for [$^{18}F$]FLT synthesis with 5 mg of precursor. Unlike method 1, a [$^{18}F$]F-incorporation yield of 91.4% was achieved from the same amount of precursor in method 2.