• 대한화학회지
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• 제20권1호
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• pp.59-72
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• 1976

수소화붕소아연의 선택환원성을 조사하기 위하여 대표적 유기화합물 54종을 택하여 수소화붕소 아연과 일정한 조건 (THF 용액, 실온, 수소화이온의 농도 : 0.5M, 유기화합물의 농도 : 0.125M)하에서 반응시켜 대략의 반응속도와 정량관계를 알아보았다.

• 분석과학
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• 제17권5호
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• pp.410-415
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• 2004

본 연구에서는 담배 흡연과 관련된 유해성분들의 발생특성을 비교하기 위하여, BTEX를 위시한 주요 방향족 VOC 성분과 포름알데하이드와 아세트알데하이드를 포함하는 카보닐 화합물의 분포특성을 다각도로 비교하고자 하였다. 이를 위해, 직접흡연에 해당하는 exhaled mainstream smoke (EMS)와 간접흡연에 해당하는 side-stream smoke (SS) 시료 등을 분석하고, 이들의 농도분포를 비교하였다. 필터를 제거한 상태에서 흡입되는 담배 연기의 경우, 유해한 성분들이 수 백 ppm 수준의 고농도로 존재한다는 것을 확인하였다. 반면, 흡연자가 비흡연시에도 날숨을 통해 이들 성분을 수 십에서 수 백 ppb의 농도로 배출하는 것을 확인할 수 있었다. 이러한 분석결과와 날숨과 들숨의 관계로부터 주요 흡연성분들의 체내 잔류율 등을 유추해 보았다. 이러한 추정에 의하면, 방향족 및 카르보닐 성분들의 대부분이 99% 이상 체내에 잔류할 수 있다는 것을 확인하였다.

• 농약과학회지
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• 제8권4호
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• pp.258-264
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• 2004

효과적인 살충제로 pyrazole 계통의 화합물이 널리 알려졌으며, 이중에 fenpyroximate와 tebufenpyrad는 시판되고 있다. 본 연구에서는 fenpyroximate의 새로운 유도체로써 5-번 위치가 치환된 pyrazole oxime ether를 합성하였다. 본 연구의 핵심 중간체인 4-formyl-5-chloro-pyrazole 2는 ethyl acetoacetate와 methylhyazine의 축합반응으로 얻은 pyrazolone 1을 Vilsmeier-Haack chloroformylation을 통하여 합성하였다. 2에 nucleophilic aromatic substitution 반응을 하여 질소고리화합물이 5-번 위치에 도입된 pyrazole aldehyde 3a-i를 만든 후, 차레로 oxime 화합물 4a-i 그리고 oxime ether 화합물 6a-i를 각각 합성하였다. 합성된 화합물 중에서 6d는 벼멸구 (Brown Planthopper, BPH), 배추좀나방 (Diamondback Moth, DBM), 점박이응애 (Two Spotted Spider Mite, TSSM)에서 높은 활성을 보여주고 있으며, 이는 fenpyroximate의 살충활성과 비슷하였다. 본 결과는 6d가 다양한 곤충 및 응애에 대하여 효과가 우월하여 살충, 살비제로써 개발 가능성을 보여주고 있다.

• Journal of Microbiology and Biotechnology
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• 제26권1호
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• pp.80-88
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• 2016

The enzyme-catalyzed Henry reaction was realized using deep eutectic solvents (DESs) as a reaction medium. The lipase from Aspergillus niger (lipase AS) showed excellent catalytic activity toward the substrates aromatic aldehydes and nitromethane in choline chloride:glycerol at a molar ratio of 1:2. Addition of 30 vol% water to DES further improved the lipase activity and inhibited DES-catalyzed transformation. A final yield of 92.2% for the lipase AS-catalyzed Henry reaction was achieved under optimized reaction conditions in only 4 h. In addition, the lipase AS activity was improved by approximately 3-fold in a DES-water mixture compared with that in pure water, which produced a final yield of only 33.4%. Structural studies with fluorescence spectroscopy showed that the established strong hydrogen bonds between DES and water may be the main driving force that affects the spatial conformation of the enzyme, leading to a change in lipase activity. The methodology was also extended to the aza-Henry reaction, which easily occurred in contrast to that in pure water. The enantioselectivity of both Henry and aza-Henry reactions was not found. However, the results are still remarkable, as we report the first use of DES as a reaction medium in a lipase-catalyzed Henry reaction.

• 한국대기환경학회지
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• 제28권5호
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• pp.527-537
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• 2012

The increasing consumption of pseudo-petroleum products (PPP) has been disturbing the national petroleum market. The use of PPP lead to tax evasion, disturbance of sound trading principles, component corrosion of cars, and explosion accident. Also, PPP have emitted hazardous air pollutants (HAP) including the carcinogenic aromatic hydrocarbons, PAHs and aldehydes more than regular-petroleum products. It thus has potentials to cause many environmental and health care problems. In this study, benzene, toluene and xylene emissions from road transport vehicles due to the use of pseudo-gasoline are estimated for the year 2008. The results of our study provide emission estimates of benzene, toluene and xylene for the year as 405, 1,711, 717 tonne/yr, respectively for regular-gasoline. BTX emissions are calculated as 452~515, 1,882~2,264 and 732~752 tonne/yr when the amount of pseudo-gasoline is estimated to account for 6~13% for regular-gasoline consumption. BTX emissions increased as much as 12~27, 10~32, 2~5% by using pseudo-gasoline. It is found that the pseudo-gasoline should be the key component to produce HAP in urban area.

• Bulletin of the Korean Chemical Society
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• 제33권8호
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• pp.2724-2730
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• 2012

A new heterogeneous acidic catalyst was successfully prepared by impregnation of silica (Aerosil 300) by an acidic ionic liquid, named 1-(4-sulfonic acid)butylpyridinium hydrogen sulfate [$PYC_4SO_3H$][$HSO_4$], and characterized using FT-IR spectroscopy, the $N_2$ adsorption/desorption analysis (BET), thermal analysis (TG/DTG), and X-ray diffraction (XRD) techniques. The amount of loaded acidic ionic liquid on Aerosil 300 support was determined by acid-base titration. This new solid acidic supported heterogeneous catalyst exhibits excellent activity in the synthesis of 2-aryl-2,3-dihydroquinazolin-4(1H)-ones by cyclocondensation reaction of 2-aminobenzamide with aromatic aldehydes under solvent-free conditions and the desired products were obtained in very short reaction times with high yields. This catalyst has the advantages of an easy catalyst separation from the reaction medium and lower problems of corrosion. Recycling of the catalyst and avoidance of using harmful organic solvent are other advantages of this simple procedure.

• 대한화학회지
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• 제55권3호
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• pp.430-435
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• 2011

화력발전소에서 배출되는 석탄회를 이용하여 메조다공성 소재인 MCM-41을 제조하였다. 제조한 소재는 XRD, FTIR, SEM 및 EDS 방법으로 특성을 규명하였다. 이 소재의 촉매활성을 방향족 알데히드와 malonontrile의 Knoevenagel축합 반응에서 5-arylindene malononitriles의 합성에 대해 연구하였다. 이 방법의 특징은 쉬운 취급법, 안정성, 촉매의 재사용 및 생태친화성, 고수율, 짧은 반응시간, 간단한 실험과정 및 마무리 절차 등을 들 수 있다.

• 한국식품영양과학회지
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• 제27권6호
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• pp.1053-1058
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• 1998

Volatile flavor compounds in salt fermented big eyed herring were analyzed by vacuum simultaneous distillation solvent extraction/gas chromatography/mass spectrometry/olfactometry and aroma extract dilution anlaysis. A total of 44 volatile compounds were detected by GC/O analysis. Of these, 23 were positively identified, and composed of aldehydes(7), esters(5), ketones(4), sulfur containing compounds (3), aromatic hydrocarbons(2), alcohol(1) and nitrogen containing compound(1). Predominant odorants (Log3FD$\geq$5) in sample were ethyl butanoate(bubble gum /sweet candy-like), 3 methylbutyl butanoate (almond /nutty), 1 octen 3 one(earthy/mushroom like), (E,E) 2,6 nonadienal(roasted wheat/grainy), dimethyl trisulfide(soy sauce /cooked cabbage like), 2 acetylpyrazine(nutty/baked potato like) and unidentified compound(RI=1867, seaweed like).

• 생명과학회지
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• 제11권1호
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• pp.35-42
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• 2001

Irradiation-induced volatile flavor compounds in irradiated (0, 1, 3, 5, 10 kGy) pork meats were analyzed by liquid liquid continuous extraction (LLCE) and gas chromatography/mass spectrometry (GC/MS) methods. One hundred nine volatile compounds were detected in irradiated pork meats. These compounds were mainly composed of hydrocarbons (42 compounds), aromatic compounds (39), aldehydes(9), ketones(5) and miscellaneous compounds (14). Among these, three volatile compounds, such as decene, 1,2,3,4,-tetrahydro-6-methylnaphthalene and 1,2,3,4-tetrahydro-dimethylnaphthalene were selected as irradiation-induced compounds comparing with irradiation dosages in irradiated pork meats. By the high correlation coefficient with the increment of irradiation dose, however, decene (r=0.93) was considered as marker compound for detecting irradiation dosage in fresh pork meats.

• 한국수산과학회지
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• 제42권3호
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• pp.224-231
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• 2009

Volatile components in Olive Flounder fed diets containing 0, 2,5, 5.0, and 7.5% yuza (Citrus junas Sieb ex Tanaka) for 4 months were investigated. Samples were extracted by solid-phase micro extraction and analyzed by gas chromatography/mass spectrometry. Among 89 compounds detected, 82 were positively identified. Volatile compounds of Olive Flounder fed the unsupplemented diet comprised 12 acids, 10 alcohols, eight aldehydes, five aromatic compounds, nine esters, 12 hydrocarbons, four ketones, two monoterpenes, and one miscellaneous compound. Compounds identified in Olive Flounder fed the yuza-supplemented diets consisted of 10 esters, 11 monoterpenes, 13 sesquiterpenes, and two miscellaneous compounds, with the other compounds being the same as in the control. The most abundant class of compounds in flounders fed the yuza-supplemented diet was the monoterpenes, which included limonene, $\beta$-terpinene, $\beta$-trans-ocimene, and $\alpha$-terpinolene. Of the 13 sesquiterpenes identified in flounder fed the yuza-supplemented diet, bicyclogermacrene was the major volatile compound followed by allo-aromadendrene, trans-caryophyllene, and $\delta$-cadinene. Bicyclogermacrene and germacrene D content increased significantly as the yuza supplementation increased.