• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.2
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• pp.416-425
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• 1993

To investigate the characteristics of the merged jet arising from the interaction of two opposing curved wall jets over a circular cylinder in still air, mean velocity, Reynolds stresses, triple moments and integral length scale were measured using hot-wire anenometry. The turbulent kinetic energy and shear stress budget were evaluated using the measured data. The variations of the Reynolds stresses, the triple moment and integral length scale are severe in the interaction region. The pressure diffusion terms are found to be very large when compared the other terms in the interaction region. The distributions of the Reynolds stress and the triple moment in the similar region are found to be similar to those of conventional plane jets.

• Journal of Life Science
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• v.2 no.1
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• pp.11-19
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• 1992

pheromone은 생물의 체내에서 합성되고 체외로 분비되어 동종개체에 작용함으로써 특정의 생리적 변화를 유발하는 물질이다. 생물 중에서는 성장의 어느 단계에서 pheromone과 같은 물질이 관여하고 있다는 것이 알려져 있다. 또한, 단세포생물에서 세포 외로 분비하여 2개의 세포를 서로 접합시키는 물질이 있는데 이러한 물질을 성pheromone이라 부르고 있다. 특히, 효모 버섯, 조류, 섬모충류에서 연구되고 있다. 효모는 성접합형을 달리하는 두 균주가 상호pheromone을 분비, 수용하여 성분화를 행하여가고 있다. 그리고 세균에 있어서도 pheromone 양상의 물질이 세포 외로 분비되고 이 물질에 의하여 세균의 생리적 조건에 영향을 주는 예가 있다. 지금까지 알려져 있는 미생물의 성 pheromone에 대하여 크게 나누어 보면 지용성 성 pheromone과 수용성 성 pheromone으로 대별할 수 있다. 본 총설에서는 세균과 자낭균효모, 담자균효모유래의 성 pheromone 중 peptide(수용성) 성 pheromone에 대해서만 집약하였다.

• YAKHAK HOEJI
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• v.48 no.2
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• pp.135-140
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• 2004

For the development of new COX-2 inhibitors, 1,5-diarylhydantoins 5a∼5c and 1,5-diaryl-2-thiohydantoin 6a∼6c were synthesized from commercially available phenylacetic acids through esterification, bromination, C-N bond formation and cyclization. Esters 2a∼c were efficiently synthesized from the starting materials 1a∼c by refluxing in absolute methanol for 3 hours with catalytic concentrated sulfuric acid. Bromination of 2a∼c was carried out with use of N-bomosuccinimide at rt in dichloromethane. The bromine of 3a∼c was substituted with aniline in ethanol or N,N-dimethylformamide to provide 4a∼c. Hydantoins and 2-thiohydantoins were synthesized from 4a∼c by treatment of potassium isocyanate or potassium thiocyanate in dil-ethanol with triethylamine.

• YAKHAK HOEJI
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• v.36 no.1
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• pp.36-39
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• 1992

In a continuous study for the developing of the anticariogenic agents, 3,3'-diacyl-4,4'-biphenol derivatives (Fig. 2, 2 and 3) and 3,3'-bis-(1-hydroxyalkyl)-4,4'-biphenol (Fig. 3, 4 and 5) derivatives are synthesized successively from 4,4'-diphenol (Fig. 2, 1). The synthesized compounds are tested for their antibacterial activity against a cariogenic bacterium, Streptococcus mutans OMZ 176. The acyl derivatives, 2 and 3, do not show antibacterial activity, but the hydroxyalkyl derivatives, 4 and 5, reduced from the acyl group of 2 and 3, show the activity. The antibacterial activity of 2 and 3 may be inhibited due to intramolecular hydrogen bonding between the acyl group and the hydroxyl one (Fig. 4).

• YAKHAK HOEJI
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• v.44 no.3
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• pp.272-278
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• 2000

The antiinflammatory mechanism of NSAIDs is attributed to the reduction of prostaglandin synthesis by the direct inhibition of cyclooxygenase. Inhibition of prostaglandin production in organs such as stomach and kidney can result in gastric lesions, nephrotoxicity and increased bleeding. In this study, newly designed COX-2 inhibitors, synthesized 1,2-benzothiazine derivatives, were screened in vitro for selectivity of COX-1 and COX-2 inhibition properties. Lead compounds in the structure-activity relationship were studied to synthesize new highly selective COX-2 inhibitors.13 determine inhibitory effect of COX-2, synthesized 1,2-benzothiazine derivatives were screened with accumulation of prostaglandin by lipopolysaccharide (LPS) in aspirin-treated macrophages and murine macropharge cell. Some of synthesized 1,2-benzothiazine derivatives were shown to be effective as selective COX-2 inhibitory activity. Others exhibited a preferential inhibition of COX-2, although some COX-1 inhibitory activity was still present. As a conclusion, simple monomer derivatives were more active than dimer derivatives. Substitution of halogen (Br, C1) on the benzothiazine nucleus slightly enhanced inhibition activity.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1992.05a
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• pp.57-57
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• 1992

Teicoplanin은 actinoplanes teicomyceticus의 발효산물로서 vancomycin과 같은 glycopeptide 계열의 항균제이며, 그 작용기전은 세포벽 합성과정중 peptidoglycan의 중합을 억제하는 것으로 vancomycin과 유사하나 vancomycin과 달리 근육에 주사할 수 있으며 "red man's syndrome"이 생기지 않고 vancomycin보다 반감기가 길다. 그람양성균 감염증에 대한 teicoplanin의 효능 및 안전성을 조사하기 위하여, 그람양성균에 의한 감염증 또는 그람양성균과 그람음성균에 의한 혼합감염증이 확인되거나 의심되었던 환자 46명을 대상으로 teicoplanin과 vancomycin을 투여하였다. 투약 환자중 임상적인 반응을 평가할 수 있는 환자의 수는 vancomycin의 경우 투약환자 22명중 21명, teicoplanin의 경우 24명중 19명이였다. Vancomycin군중 임상적 반응의 평가에서 제외된 1명은 수술 후 흉막강에 MRSA 에 의한 농양으로 투약 29일째에 뇌출혈로 사망하였던 예로, 추적-배양검사에서는 MRSA가 제거 되었다. Teicoplanin군에서는 항균제 투여 중 간경변증에 의한 식도출혈 1예, 수술후 위장관 출혈 1예, 뇌 색전중 1예가 사망하였고, 1예는 Teicoplanin에 의한 심한 피부발진으로, 다른 1예는 봉와직염의 임상진단이 조직검사결과 악성종양의 근육침범으로 밝혀져 투약을 중단하였다.

• Biomolecules & Therapeutics
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• v.7 no.2
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• pp.164-169
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• 1999

The synthesis and antimicrobial activity of N-substituted glycol derivatives of Norfloxacin were described. Norfloxacin was treated with chloroacetyl chloride to yield chloroacetyl norfloxacin (1). This compounds was reacted with alkyldiamines to afford bivalent ligand quinolone carboxylic acids (2-6), which was added to pivaloyloxymethyl chloride to give bivalent ligand pivaloyloxymethyl quinolone carboxylates (7-11). Chloroacetyl norfloxacin (1) treated with alkylamines to obtain monovalent ligand quinolone carboxylic acids (12-15), which was reacted with pivaloyloxymethyl chloride to get monovalent ligand pivaloyloxymethyl quinolone carboxylates (16-19). Free carboxylic quinolones (2-6, 12-15) showed little stronger activities to their pivaloyloxymethyl esters (7-11, 16-19). In monovalent ligand quinolone analogues, longer a1kyl chain com-pounds showed stronger activities than shorter one.

• Journal of environmental and Sanitary engineering
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• v.15 no.4
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• pp.4-13
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• 2000

산업공정에서 배출되는 대기오염물질 및 유독성가스를 제거하기 위한 방법에는 여러 가지가 적용되고 있으나, 본 연구에서는 충전탑을 이용한 흡수원리로써 오염물질을 처리하는데 후력학적 특성에 대해서 연구하였다. 즉 환경보호와 화학공업에서 에너지 절약 측면에 충전탑의 사용이 증가되고 있으며, 충전물의 재료로는 플라스틱, 금속 및 세라믹 등으로 제작되며 종류로는 VSP-ring, Hiflow-ring, Hackette, Top-packing, Envi-pac 등이 있고 사용범위는 정류와 증류, 흡수 및 탈착과 액체와 액체의 추출공정 등에 효율적으로 사용되고 있다. 산업현장에서는 과거에 주로 사용되어온 Intalox-saddle, Rasching-ring, Pall-ring 등의 재래적 충전물은 압력손실과 물질전달, 에너지 절약 및 효율성이 좋은 격자형 충전물의 개발로 인하여 점점 사용이 감소되고 있는 추세이며, 최근에는 합성수지로 제조된 충전물 NSW-ring, Hiflow-ring, Envi-pac 등은 실험 결과에 의해서 재래적인 충전물 Raschig-ring과 Pall-ring보다 높은 상대적인 공간체적과 충전높이에 따른 낮은 압력손실과 함께 높은 부하 한계치에 대하여 효율적이고 가벼운 분리작용에 의한 수력학적 특성이 증명되어졌다. 격자형 충전물이 산업에 적용되기 위해서는 압력손실과 액체함량, 부하 한계치 가스상 또는 액상 물질전달의 특성을 규명하는 것이 중요하다. 따라서 본 연구에서는 가수와 액체의 역류흐름에 의한 수력학적 특성과 물질전달 실험결과를 나타내었다.

• Journal of Environmental Health Sciences
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• v.7 no.2
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• pp.107-111
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• 1981

Thirteen Carbanilides, P-chloro, bromo, methyl, ethyl, methoxy and ethoxy carbanilides, 4,4'-dichlorocarbahilide, and 4-bromo, methyl, ethyl, methoxy and ethoxy 4'-chlorocarbanilides have been newly synthesized by reacting P-phenetidime, P-anisidime, anilime, P-chloroanilime, P-bromoanilime, P-methoxy aniline, and P-ethoxy anilime with phenyl and P-chlorophenyl isocyanate, respectively. The compounds generally exhibited antibacterial activity against Escherichia coli, and staphylococcus aureus. The results obtained were as follows 4-chlorocarbanilide and 4,4'-clichlorocarbanilide were active against Eschrichia Coli, and Staphylococcus aureus at the concentration of 50 ug/ml. 4-methyl-4'-chloro carbanilide, and 4-ethoxy-4'-chloro carbanilide were active against Escherichia Coli at the concentration of 100ug/ml. 4-methyl-4'-chloro canbanilide were active against Staphylococcus aureus at the concentration of 50ug/ml.

• Journal of Environmental Health Sciences
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• v.7 no.2
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• pp.113-117
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• 1981

Twelve benzothiazolyl and 6-substituted benzothiazoly phenyl and chlorophenyl ureas have been newly synthesized by reacting 2-amino benzothiazole and 2-amino-6-substituted benzothazole with three or four phenyl and chlorophenyl isocyanate, respectively. The structures of these compounds were determined by measurement of the molecular weights and elementary analysis as well as IR spectrophotometry. The compounds generally exhibited antibacterial activity against Staphylococcus aureus and Escherichia coli in the concentration of $50\mu g/ml$. The compounds containing chloro group exhibited stronger antibacterial activity than those containing methyl group against Eschichia coli. The difference in the antibacterial activity according to the substituted group (phenyl, o-, m-, and p-chlorophenyl) was also noted. The compounds containing o-chlorophenyl group, on the whole, exhibited more potent growth-inhibitory activity againsts staphylococcus aureus.