• 폴리머
• /
• 제26권3호
• /
• pp.293-299
• /
• 2002

항균제인 m-크레졸을 아크릴로일클로라이드와 반응시켜 m-크레실아크릴레이트를 합성하고 이를 메틸메타크릴레이트와 아크릴산과 3성분 라디칼 공중합시켜 m-크레졸 moiety를 가지는 고분자를 합성하였다. 이들 고분자중의 m-크레실아크릴레이트단위는 핵자기공명스펙트라로부터 각각 4.7 mol%와 10.1 mol%로서 측정되었다. 이들 고분자의 수평균분자량은 12000∼15000이었다. 이들 고분자는 가수분해를 통해 m-크레졸을 방출하였고 방출되는 그 양은 pH증가에 따라 증가하였다. 이것은 고분자중의 아크릴산 단위의 카르복실기의 수소가 pH증가에 따라 해리하기 용이하기 때문인 것으로 설명된다. 아울러 이들 고분자는 양성균 S. aureus와 음성균 E. coli에 대해서 항균성을 나타내었다.

• 농업과학연구
• /
• 제11권2호
• /
• pp.315-321
• /
• 1984

0.1M tetraethylammoniumperchlorate (TEAP)를 지지전해질로 한 acetonitrile속에서 direct current (DC), differential pulse (DP) polarography 및 cyclo voltammetry (CV) 방법에 의한 Sumithion의 전기화학적 환원반응은 -1.0~-2.50volt vs. Ag-AgCl 범위에서, 제1단계로 P-Oph 결합의 분열에 의하여 dimethylthiophosphonyl radical과 p-nitro-m-cresol이 생성되는 1전자 유사가역반응이 일어나고, 제2단계는 전형적인 1전자 비가역 반응으로 dimethylthiophosphonyl radical이 dimethylthiophosphonate가 되며, 제3단계 반응은 2.7volt vs. Ag-AgCl의 높은 음전위에서 p-nitro-m-cresol은 4전자 비가역반응에 의한 nitro group의 환원으로 p-hydroxy-amino-m-cresol이 생성되는 총 3단계의 비가역적인 electron-transfer chemical reaction (EC) 메카니즘으로 전극반응이 진행됨을 알았다.

• 한국약용작물학회지
• /
• 제28권1호
• /
• pp.29-37
• /
• 2020

Background: Although Gastrodia elata contains the valuable, bio-active compounds gastrodin and 4-hydroxybenzyl alcohol (4-HBA), it also contain ρ-cresol, which is a major source of an objectionable pig slurry-like odor. Accordingly, this study was performed to determine the deodorization effect of Diaion HP-20 resin on a G. elata extract. Methods and Results: Using Diaion HP-20 with an increasing concentration of ethanol, an extract of G. elata was fractionated into 15 fractions, which were anlayzed to determine their concentrations of active compounds and ρ-cresol. The gastrodin, 4-HBA, total phenolics, and ρ-cresol concentrations of the G. elata extract were 403.13, 408.15, 2,476.09, and 11.77 ㎍/㎖, respectively. Among the different fractions, gastrodin and 4-HBA were detected in fractions 3 to- 6, and 4 to- 10, respectively whereas total phenolics were detected in all samples, with fractions 5 to- 7 being characterized by higher concentrations than were the other fractions. ρ-Cresol was detected in fractions 12 to- 15, at concentrations ranging from 0.39 ㎍/㎖ to 6.05 ㎍/㎖ with the highest concentration detected in fraction 14. The fractions containing ρ-cresol could be selectively separated from the G. elata extract without the loss of major bio-active compounds such as gastrodin and 4-HBA. Conclusions: The results of this study indicate that a deodorizing method using Diaion HP-20 resin can be considered for improving the sensory qualities of G. elata extract without a loss of the major bio-active compounds.

• 폴리머
• /
• 제26권1호
• /
• pp.88-97
• /
• 2002

ortho-cresol novolac형 에폭시/페놀 경화제/triphenylphosphine 수지 시스템의 화학 레올로지 특성에 미치는 아민 실록산 개질제의 영향을 검토하였다. DSC측정으로부터 아민 개질제에 의해 경화 속도와 전환량이 증가하였으며 유리전이온도의 증가도 관찰할 수 있었다. 또한, 저장 탄성률과 손실 탄성률의 교차점으로부터 구한 겔화 시간 및 임계 전환량의 감소를 확인할 수 있었다. 이것으로부터 등온 경화반응이 빠르게 진행됨으로써 점도가 상승하는 것을 알 수 있었다. 전환량의 함수로 얻어진 유리전이온도와 측정된 점도로부터 modified WLF 방정식에서의 $C_1$ 및 $C_2$를 온도 함수로써 나타낼 수 있었으며, 유리전이온도와 $C_1$ 및 $C_2$를 modified WLF 방정식에 적용함으로써 등온 경화반응에 따른 점도변화를 정확히 예측할 수 있었다.

• 대한디지털의료영상학회논문지
• /
• 제15권2호
• /
• pp.69-76
• /
• 2013

We checked the existence of bacteria at DR equipment, radiation generator and cassette in 'D university' to propose optimized management method for bacteria and disinfection at DR equipment, radiation generator and cassette at used in radiographic laboratory of the department of radiology. The infected region is treated by alcohol and cresol and compared before spraying and after spraying for 1, 3, 5 and 10 minutes. As time goes on, amount of bacteria colony decreases significantly. The Cresol is useful to disinfect the diminutive devices. However alcohol disinfection, at least 5 minutes later, and hand washing before practical training and shooting image is recommended due to the big and fixed radiography equipment which cause the soakage.

• Corrosion Science and Technology
• /
• 제5권2호
• /
• pp.62-68
• /
• 2006

Solvent free high solid coatings are increasingly used as they posses number of advantages such as, lower cost per unit film thickness, better performance and eco-friendliness. In the present study polymeric film-forming materials such as aniline-novolac (ANS), cresol-novolac (CNS) and acrylic copolymer blended cresol-novolac (ACNS) coating materials have been prepared. The corrosion resistance properties of the prepared high solid coating materials have been evaluated through potential-time, potentiodynamic polarization and electrochemical impedance studies (EIS). Among the three coating systems, cresol-novolac polymer coated substrates offer better corrosion resistance property and the order of the performance was found as CNS > ACNS > ANS. We can recommend these systems for use in automobile applications.

• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2000년도 춘계학술발표대회
• /
• pp.434-437
• /
• 2000

Streptomyces setonii(ATCC 39116) is a thermophilic gram-positive soil bacteria which undergoes an ortho-cleavage pathway in the presence of phenol or benzoate as a sole carbon and energy source. The specific activities of catechol-1,2-dioxygenase in S. setonii, a key enzyme in ortho-cleavage pathway, were induced by various aromatic compounds such as benzoate, phenol, m-hy-benzoate, p-hy-benzoate, catechol, o-cresol, m-cresol, p-cresol, benzene, toluene, ethyl-benzene, 2-chloro-phenol, and 4-chloro-phenol, among which the phenol showed the highest inducibility in the presence of 0.01% glucose. More than 0.1% glucose dramatically reduced the specific activities of catechol-1,2-dioxygenase induced by most of the single aromatic compounds tested.

• Archives of Pharmacal Research
• /
• 제28권7호
• /
• pp.765-769
• /
• 2005

The essential oil fraction of Ostericum koreanum was analyzed by GC-MS. Inhibiting activities of this oil and its main components were tested by the broth dilution assay and disk diffusion test against one antibiotic-susceptible and two resistant strains of Salmonella enteritidis and S. typhimurium, respectively. The GC-MS analysis revealed thirty-four compounds; the main components were $\alpha$-pinene (41.12%), $\rho$-cresol (17.99%) and 4-methylacetophenone (7.90%). The essential oil of O. koreanum and its main components were significantly effective against the tested antibiotic-susceptible strains as well as against the resistant strains of the two Salmonella species, with MICs (minimum inhibitory concentrations) ranging from 2 mg/mL to 16 mg/mL. The anti-Salmonella effects of the oils were dose-dependent on $M\"{u}ller-Hinton$ agar plates in this experiment. Additionally, checkerboard titer test results demonstrated significant combined effects of streptomycin and O. koreanum oil or cresol, one of the main components of this oil, against the two streptomycin resistant strains of S. typhimurium, with FICIs ranging from 0.12 to 0.37.

• 한국환경과학회지
• /
• 제11권4호
• /
• pp.399-403
• /
• 2002

This study was designed to analyse the odor from Nam river. The characteristic odor in the water occurred from geosmin and phenol, p-cresol and indol were detected from sediment/water samples. The others were detected as alcohols and fat acid compounds. Algae causing odor and taste were identified as Oscillatoria sp. and Synedra acus. 15 species of phytoplankton, a zooplankton, an eelworm and chironomus were identified in water/sediment sample.

• 한국표면공학회:학술대회논문집
• /
• 한국표면공학회 2012년도 춘계학술발표회 논문집
• /
• pp.290-290
• /
• 2012

산성Sn도금액은 첨가제에 어떠한 유기화합물을 사용하는가는 도금장치나 석출상태로써 결정할 수 있다. Hothersall과 Bradshaw는 Cresol술폰산을 첨가하여 도금액 안정성 향상을 발견했다. Cresol술폰산은 $Sn^{2+}$의 안정제이며, Gelatine은 분산제기능을 한다. 붕 불화용액은 Sn농도를 높일 수 있고, $2{\sim}12A/dm^2$의 고 전류밀도의 도금이 가능하다. 1937년 Schloetter가 개발하여 미국의 제철회사에서 사용되었다. 본고에서는 최근의 습식주석도금의 특성을 중심으로 기술하였다.