• Journal of the Korean Chemical Society
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• v.27 no.2
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• pp.157-164
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• 1983

N-Methylidene-2,6-diethylaniline (III) was prepared by the reaction of 2,6-diethylaniline (II) with an excess paraformaldehyde. The protons of N=$CH_2$in the compound III exhibited a second order NMR spectrum. The compound III reacted with bifunctional chlorocarbonylsulfenyl chloride(IV) to give N-(chloromethyl)-N-(2,6-diethylphenyl)-carbamoylsulfenyl chloride(V). The reaction of the compound V with various alcohols resulted in the formation of Alkyl N-(chloromethyl)-N-(2,6-diethylphenyl)-carbamoylsulfenate esters(VI${\sim}$XVI) in 71${\sim}$95% yields. The compound VI${\sim}$XVI decomposed gradually, but the thermal rearrangement of S-O bonding to S=O bonding was not found. The nucleophilic attack of an excess alcohol to the compound Ⅴ was made on both divalent sulfur and ${\alpha}$-carbon of N-chloromethyl group. The corresponding substituted products(XVII, XVIII) had considerable stability.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1363-1365
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• 2001

다공질 실리콘(PSi)의 형성방법중에 가장 주된 방식인 전기화학법은 매우 범용화된 기술이다. 이러한 전기화학법을 이용한 PSi 제작방식에 있어 HF 가 함유된 전해액과 첨가되는 첨가제는 PSi 형성에 매우 중요한 역할을 한다. 전해액에 첨가되어지는 첨가재는 종류에 따라 전해질과 기판사이의 친수성 및 전해액의 표면장력을 작게 하는 역할을 하며, 그 밖의 기판 표면 상태변화의 원인으로서 양극산화 공정에 많은 변수로 작용한다. 본 논문에서는 기존의 에틸알콜을 함유한 HF 전해액과 새로운 용매를 함유한 HF 전해액에 대한 PSi의 형성을 광학 현미경 사진과 시간에 따른 전류 및 전압 특성 곡선으로 비교 분석하였으며, 기존 식각 용액을 사용했을 경우의 표면 식각현상과 형성구조의 불균일성 등을 해결할 수 있었다.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.2
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• pp.145-146
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• 2001

본 분석방법은 토양중에 방향성화합물을 함유한 유류 존재를 스크리닝하는 방법으로 ASTM(The American Society for Testing and Materials)에 등록되어 있으며, 수분 제거제를 이용하여 토양수분에 의한 정량 오차를 줄이고 UV-Spectrophotometer로 정량한다. 오염된 유류의 종류를 알고 있으나 동일한 유류를 구하지 못할 경우에는 일반적으로 동일종에서 얻어진 계수로 농도를 추정하며, 오염된 유류의 특성을 모를 경우에는 본 방법으로 오염여부 판단만이 가능하다. 그러나 토양에 오염된 것과 동일한 유류로 검량선을 작성할 경우에는 대략적인 정량도 가능하며, 분석방법을 요약하면 다음과 같다. 일정량의 토양시료에 CaO를 첨가하여 토양수분에 의한 영향을 제거한 뒤 이소프로필알콜(isopropyl alcohol)로 추출하여 여과한다. 여과액을 254nm의 UV파장에서 흡광도를 측정하여 오염된 것과 동일한 유류로 작성된 검량선을 이용하여 정량한다.

• Korean Chemical Engineering Research
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• v.47 no.6
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• pp.740-746
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• 2009

In the present study, the drowning-out crystallization of L(+)-calcium lactate was investigated in order to develop the crystallization separation process. The crystallization of the calcium lactate was induced by injecting the alcoholic anti-solvent into the aqueous solution of calcium lactate and the control of the calcium lactate crystal size during the crystallization was primarily investigated under the consideration of the anti-solvent species, anti-solvent composition and agitation speed as the key operating factors. Alcohols of methanol, ethanol, n-propanol and i-propanol were used as the anti-solvent for the drowning-out crystallization. Prior to the crystallization experiment, the solubility of calcium lactate in the water-alcohol mixture was measured along with the variation of the alcohol species and composition, which was necessary to estimate the supersaturation level of the crystallization. By the drowning-out crystallization, the calcium lactate crystals of the fabric shape were obtained. Using the ethanol as the antisolvent, the fabric crystals close to the needle shape were produced. However, the hairy crystals were obtained by using the propanol as the anti-solvent. Due to such morphological features, the crystals was highly apt to form the aggregates. The aggregation of the crystals was intensified as increasing the alcohol fraction in the water-alcohol mixture. Meanwhile, the agitation caused the breakage of crystals, resulting in the decrease of the crystal size. Therefore, the crystal size in the crystallization was predominantly determined by the competition between the crystal aggregation and breakage.

• Korean Journal of Biological Psychiatry
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• v.3 no.2
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• pp.222-239
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• 1996

The purpose of this study was to evaluate the effects of alcohol on the psychomotor performance and subjective assessment in healthy Korean adults with acetaldehyde dehydrogenase I(ALDH-I) isozyme variance. A total of 20 male subjects, half with active ALDH-I and the other half with inactive ALDH-I, were selected through both a self-reporting questionnaire examining alcohol sensitivity and the Higuchi's ethanol patch test detecting ALDH-I deficiency. In a doule-blind, placebo-controlled cross-over design, each subject consumed four doses of alcohol(0.25, 0.5, 0.75, 1.0g/kg) and placebo on five separate occasions at weekly intervals, Treatment order was fully balanced using a $5{\times}5$ Latin square, Psychomotor performance tests[coritical flicker fusion threshold(CFF) and choice reaction time(CRT)] and self-estimate questionnaires were conducted at baseline and at time points of 20, 40, 60, 90, 120, 150, 180 minutes after consuming the test drug for 20 minutes, Blood alcohol concentrations(BACs) using breath analyzer were measured at baseline and at time points of 10, 20, 30, 40, 50, 60, 75, 90, 105, 120, 150, 180 minutes after drinking, The BACs and the mean changes in the psychomotor performances and subjective assessments from pre-alcohol baseline, were compared between the two groups. The findings were summarized as follows : 1) BACs were tended to be higher in the inactive group than the active in all of the four alcohol doses. However significant group differences were only after the 0.5g/kg dose of alcohol. 2) The inactive group showed significant impairment in CFFT at most time points alter 0.75 and 1.0g/kg doses of alcohol. 3) In CRT, total reaction time(TRT) significantly prolonged in the inactive group than the active group at 20 minutes after 0.25 and 1.0g/kg doses of alcohol and at 40, 60, 90 minutes alter 0.75g/kg dose of alcohol. In the inactive group, recognition time component significantly increased at 20, 60, 90 minutes after 1.0g/kg dose of alcohol, while movement time component significantly increased at 40, 60 minutes after 0.75g/kg dose of alcohol. 4) Subjective evaluation of the effect of alcohol revealed that physical and mental conditions as well as a self-estimate of the effects of alcohol on performance were significantly worse in the inactive group than the active at some time points alter all of the lour alcohol doses, wihch were more pronounced after 0.75 and 1.0g/kg doses of alcohol. 5) Most of the group differences mentioned above, still remained statistically significant after BAC was entered as a covariate, These findings demonstrated that the alcohol sensitivity is higher in individuals with inactive ALDH-I than those with active ALDH-I both on the subjective assessments and the objective psychomotor performances. Furthermore, these results suggest thai the alcohol sensitivity may be determined by acetaldehyde concentration rather than BAC per se. In future studies, after more accurate genotyping for ALDH-I, the relationships between BAC, acetaldehyde concentration and alcohol sensitivities should be clearly defined.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.235-242
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• 2007

This study was conducted to investigate the effect of aerosolized chemical sanitizers on inhibiting foodborne pathogens such as Escherichia coli O157:H7, Salmonella typhimurium, and Listeria monocytogenes. Five domestic commercial sanitizers subjected to five groups of sanitizer (chlorine-based, hydrogen peroxide-based, Iodophor-based, quaternary ammonium-based, and alcohol-based sanitizers) were aerosolized by an aerosol generator into a model cabinet and treated in laboratory media containing three pathogens for 1 h at room temperature. Aerosolized hydrogen peroxide-based and quaternary ammonium-based sanitizers were effective at inhibiting levels of E. coli O157:H7 (ca. 4-9 log reductions) whereas other aerosolized sanitizers such as chlorine-based, Iodophor-based, and alcohol-based sanitizers did not significantly reduced the levels of E. coli O157:H7. For S. typhimurium, the only aerosolized hydrogen peroxide-based sanitizer was effective and resulted in ca. 5-9 log reduction. Aerosolized hydrogen peroxide-based, Iodophor-based, and quaternary ammonium-based sanitizers significantly reduced levels of L. monocytogenes and especially, aerosolized quaternary ammonium-based sanitizer was strongly effective to kill L. monocytogenes, resulted in higher than 8.8 log reduction. And there was no special trend in inhibitory efficacy of sanitizers aerosolized by 1.6 or 2.4 MHz aerosol generators. From these results, aerosolization has great potential for use in commercial applications however it's efficacy could be very different depending on type of sanitizers.

• Transactions of the Korean hydrogen and new energy society
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• v.17 no.1
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• pp.98-108
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• 2006

본 연구에서는 이 단계 연속 바이오 수소/메탄 생산공정의 경제성을 조사하였다. 경제적 관점에서 다양한 수소 및 메탄 발효용 생물반응기를 비교 평가하였다. 이를 바탕으로 포도당으로부터 일 단계 수소발효를 위해 고온 trickling biofilter 반응기 (TBR, $100\;m^3$ 규모)를, 일 단계 반응의 부산물로 생성된 유기산과 알콜류의 이 단계 메탄전환을 위해 고온 upflow anaerobic sludge 반응기 (UASB; $700\;m^3$ 규모)를 선정하였다. 본 이 단계 공정의 수소생산 비용은 $$\;0.26/Nm^3$으로 계산되었고, 이는 고온 TBR 반응기만을 이용한 경우보다 약 30 % 낮았다. 이 단계 공정의 낮은 수소생산 비용은 높은 에너지 회수율과 낮은 슬러지 처리비용에 의한 것이었다. 생물학적 수소 생산공정의 경제성은 탄소원의 종류, 생물반응기의 형태 등 여러 인자에 의해 변경될 수 있으나, 본 연구결과는 향후 연구를 위한 유용한 기준으로 고려될 수 있다.

• Membrane Journal
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• v.6 no.4
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• pp.250-257
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• 1996

Surface crosslinked chitosan composite membranes were prepared with glutaraldehyde and surfuric acid. Effects of neutralization for complex between chitosan and acetic acid and of water permeability for substrate membranes on pervaporation performance were investigated. For ionically crosskinked membranes, effect of active layer thickness on separation factor of water/ethanol mixture was studied. With increasing the water permeability of the substrate, the membrane showed an increased separation factor, while it maintained a constant permeate flux. Neutralized chitosan composite membranes revealed a decreased separation factor and a constant permeate flux. When the thickness of the active layer increased, an optimum crosslinking time to achieve higher separation factor shifted to a prolonged times.

• Food Science and Preservation
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• v.10 no.3
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• pp.417-420
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• 2003

In order to study optimum culture condition of yeast medium added deep seawater, we examed samples with 9 yeast strains. The growth rate were measured for Saccharomyces cerevisiae 10, 11, 12, 901 and RCY and Saccharomyces kluyvery DJ97, Saccharomyces cerevisiae YJK, JK99, CMY-28 etc.. The growth of S. cerevisiae 12 was found most active in the deep seawater(hardness 500). The growth rate of S. cerevisiae 901 on medium containing deep seawater(hardness 1000) was faster than that of the yeast on medium without deep seawater. The use of deep seawater on the growth of Sacch.cerevisiae kluyvery DJ97 revealed maximum growth under the condition of hardness 200 of deep seawater and 10％ of sugar concentration.

• Journal of Life Science
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• v.21 no.2
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• pp.292-299
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• 2011

This study compared volatile flavor profiles of 4 commercial vinegar beverages (Italian vinegar beverage (IVB), Japanese vinegar beverage (JVB), Japanese Yuzu-Ponz (JYP), and Korean white wine vinegar beverage (KWVB)). Flavor components of vinegar beverages (VBs) were determined using SPME/GC/MSD. The profiles of VBs were as follows; IVB (11 acids, 17 esters, 10 alcohols, 8 aldehydes, 3 terpenes, 4 aromatic hydrocarbons, 9 ketones), JVB (7 acids, 8 esters, 9 alcohols, 7 aldehydes, 13 terpenes, 7 aromatic hydrocarbons, 1 ketones, 3 miscellaneous compounds), JYP (3 acids, 12 esters, 8 alcohols, 7 aldehydes, 63 terpenes, 6 aromatic hydrocarbons, 2 ketones, 5 miscellaneous compounds), KWVB (10 acids, 10 esters, 9 alcohols, 8 aldehydes, 2 terpenes, 5 aromatic hydrocarbons, 4 ketones, 2 miscellaneous compounds). IVB and JVB showed similar flavor compositions (acids, ketones and esters in particular), whereas major components in JYP and KWVB were terpenes (79.6%) and acids (81.0%), respectively. Five compounds including 2-phenylethyl acetate (floral, fruity, sweet odor), 2-phenylethanol (floral, rose odor), vitispirane (fruity odor), geranylacetone (fragrant odor) and acetic acid were identified as major components in balsamic vinegar beverages.