• 한국잡초학회지
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• 제16권4호
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• pp.292-300
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• 1996

벼 담수직파시 제초제에 의한 약해의 원인을 구명하고자 온도, 용액의 pH, 수심, 토성 및 영양(營養)의 유무(有無) 등의 조건하에서 실험을 실시한 결과는 다음과 같다. 1. Bensulfuron methyl 및 pyrazosulfuron-ethyl 처리는 20/$11^{\circ}C$에서 30/22$^{\circ}C$에서보다 벼 생육 억제 정도가 컸으며, 특히 근부(根部)에서 현저히 컸다. Dimepiperate 및 molinate 처리는 저온 (20/$11^{\circ}C$) 고온(30/$22^{\circ}C$) 에서 생육억제 정도가 컸으며 경엽부(莖葉部)에서 현저하였다. 2. 무영양(無營養) 조건에서는 bensulfuron methyl 처리에서, 영양(營養)조건 에서는 pyrazosulfuron-ethyl의 처리에서 생육 억제 정도가 컸다. 3. pH3.5, 5.5, 7.5 및 9.5 용액에 bensulfuron methyl 및 pyrazosulfuron-ethyl 처리시 벼 생육은 pH3.5 및 5.5의 낮은 pH에서 저조하였으며, 무처리 대비한 생육 억제정도는 bensulfuron methyl 처리는 pH5.5 및 7.5에서 pyrazosulfuron-ethyl 처리는 pH7.5 및 pH9.5에서 낮았다. 4. 수심 6cm의 심수조건에 bensulfuron methyl 및 pyrazosulfuron-ethyl 처리시는 근부(根部)의 생육이, dimepiperate 및 molinate의 처리는 경엽부(莖葉部)의 생육이 크게 억제되었으며, 특히 dimepiperate처리는 90% 정도 억제되었다. 또한 pyrazosulfuron-ethyl+molinate의 처리에서 bensulfuron methyl+dimepiperate 처리보다 경엽부(莖葉部)의 억제정도가 컸다. 5. Pyrazosulfuron-ethyl 처리는 무비구는 식양토에서, 시비구는 사양토에서 생육저해 정도가 컸으며, bensulfuron methyl 처리는 사양토에서 생육이 저조한 경향이었다.

• 폴리머
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• 제37권2호
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• pp.135-140
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• 2013

Poly(methyl acrylate)-poly(acrylonitrile) 공중합체의 응력완화 실험은 용매기를 부착한 인장 시험기를 사용하여 여러 온도의 공기 중, 증류수, pH 3, 7, 11 용액에서 실행하였다. Ree-Eyring and Maxwell 모델로부터 얻은 완화스펙트럼 식에 실험적인 응력완화 곡선을 대입하여 poly(methyl acrylate)-poly(acrylonitrile) 공중합체의 완화스펙트럼을 얻었다. 완화스펙트럼의 계산은 Laplace 변환법을 사용한 컴퓨터 프로그램을 이용하였다. 이들 시료의 완화스펙트럼은 유동단위의 분자량과 자체확산 분포와 밀접한 관계가 있음을 알 수 있었다.

• 약학회지
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• 제37권6호
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• pp.555-560
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• 1993

Methyl 3-[(phenylsulfonyl)methyl]-1, 4, 8-trimethoxy-2-naphthoate(7) preparad by 3 steps was condensed with 5-ethyl-2-cyclohexen-1-one(8) to afford the teracyclic aromatic ring system compound 10, which was stepwise converted into the precursor of 11-Deoxy-$\beta$-rhodomycinone by means of various functional groups transformation.

• Bulletin of the Korean Chemical Society
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• 제11권5호
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• pp.431-434
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• 1990

Template condensation reaction of diethylenetriamine, ethylenediamine, methylamine, and formaldehyde in the presence of Ni(II) or Cu(II) ion yields new saturated hexaaza macrobicyclic complexes $[Ni(C)]^{2+}\;and\;[Cu(C)]^{2+}$, where C is 8-methyl-1,3,6,8,10,13-hexaazabicyclo[11,2,1]hexad ecane. The macrobicyclic complexes contain one 1,3-diazacyclopentane ring and one methyl pendant arm in the ligand C and have square planar geometry with 5-6-5-6 chelate ring sequence. Synthesis, characterization, and the properties of the macrobicyclic complexes are described.

• 한국식품영양과학회지
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• 제21권3호
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• pp.302-307
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• 1992

들깻잎의 메탄을 추출물이 S. typhimurium TA98과 100에서 aflatoxin B$_1$(AFB$_1$)의 돌연변이 유발성을 억제시키는 효과가 있었다. 메탄을 추출물을 silica gel column을 사용하여 더욱 분획하여 항돌연변이 효과를 시험하였으며, 그중 효과가 가장 컸던 fraction 중의 화합물을 분리, 동정한 결과 2-ethoxy acetate, 1, 2, 3, 4-tetramethyl-cis-cyclobutene, 두 개의 methyl 11, 14, 17-eicosatrienoate 이성체, 12-acetyl-9-octadecanoic acid, 그리고 Phytol이 있음이 잠정적으로 밝혀졌다. Phytol과 methyill, 14, 17-eicosatrienoate의 표준품을 사용하여 AFB$_1$및 Trp-P-2에 대한 항돌연변이 효과를 시험한 결과 그 효과가 컸음이 밝혀졌다.

• Bulletin of the Korean Chemical Society
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• 제11권2호
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• pp.144-149
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• 1990

Conformational free energy calculations using an empirical potential function (ECEPP/2) and the hydration shell model were carried out on the sulfonylurea herbicides of bensulfuron methyl (Londax) and metsulfuron methyl (Ally). The conformational energy was minimized from starting conformations which included possible combinations of torsion angles in the molecule. The conformational entropy of each conformation was computed using a harmonic approximation. To understand the hydration effect on the conformation of the molecule in aqueous solution, the hydration free energy of each group was calculated and compared each other. It was found that the low-free-energy conformations of two molecules in aqueous solution prefer the overall folded structure, in which an interaction between the carbonyl group of ester in aryl ring and the first amido group of urea bridge plays an important role. From the analysis of total free energy, the hydration and conformational entropy are known to be essential in stabilizing low-free-energy conformations of Londax, whereas the conformational energy is proved to be a major contribution to the total free energy of low-free-energy conformations of Ally.

• Archives of Pharmacal Research
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• 제13권3호
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• pp.240-245
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• 1990

Asymmetric 2, 6-dimethyl-4-aryl-1, 4-dihydropyridine-3, 5-dicarboxylate with [N-(3, 4-methylenedioxybenzyl)-N-methyl] aminoethyl group as the ester moiety and related 1, 4-dihydropyridine derivatives were prepared and tested for the effects on vascular smooth muscles. 2-6-dimethyl-4-(3'-nitrophenyl)1-4-dihydropyridine-3, 5-dicarboxylic acid 3-[N-(3', 4-methylenedioxybenzyl-N-methyl] aminoethyl ester 5-methyl ester (11) and 2, 6-dimethyl-4-(3'-nitrophenyl)-1, 4-dihydropyridine-3, 5-icarboxylic acid 3-[N-2', 3'-methylenedioxybenzyl)-N-methyl] aminoethyl ester 5-ethyl ester (150 showed potent vasodilating activities $IC_{50}$($10_{-8}M$) was 2, 6 and 2.7 for 11 and 15, compared with 3.5 for nicardipine.

• 한국응용과학기술학회지
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• 제24권3호
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• pp.296-300
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• 2007

This paper presents applicability of photocatalytic decomposition of methyl mercaptan using $TiO_2$. A quartz reactor was used in order to elucidate reaction pathway in photocatalytic decomposition of methyl mercaptan. Experimental results showed that more than 99.9% of methyl mercaptan was decomposed within 30 minutes. It was found that the photocatalytic decomposition of methyl mercaptan followed pseudo first order and its reaction coefficient was $0.05min^{-1}$ During 30 minutes in the photocatalytic reaction, the concentration of methyl mercaptan, dimethyl disulfide, $SO_2$, $H_2SO_4$, COS, $H_2S$ were determined. These results showed that 64% of methyl mercaptan were compensated for the increase in sulfur after 30 minutes through the mineralization. The proposed main photocatalytic decomposition pathway of methyl mercaptan was methyl $mercaptan{\rightarrow}dimethyl$ $disulfide{\rightarrow}SO_2{\rightarrow}H_2SO_4$.

• 대한화학회지
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• 제27권6호
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• pp.441-448
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• 1983

여러가지 브롬화비닐 화합물들 ((Z)-1-bromopropene, 1-bromo-2-methylpropene, 2-bromo-3-methyl-2-butene, (E)-ethyl 2-methyl-3-bromo-2-propenoate, 1-bromo-cyclohexene)과 올레핀 화합물인 ethyl acrylate, methyl methacrylate, ethyl crotonate, allyl cyanide, ethyl 3-butenoate, ethyl 4-pentenoate와 methyl 10-undecenoate를 palladium acetate촉매와 triorthotolyphosphine 및 triehylamine존재 하의 수득율로 얻었으며 이들 생성물의 입체화학도 규명하였다. 위의 방법을 이용하므로써 ethyl 3-butenoate, ethyl 4-pentenoate와 methyl 10-undecenoate에 의한 4개, 5개 및 11개 탄소-탄소 결합의 확장도 가능하였다.

• 한국응용과학기술학회지
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• 제16권1호
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• pp.83-94
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• 1999

Glycoside fatty acid esters were synthesized by lipase-catalyzed glycosylation of fatty acids with methyl glycoside in solvent and solvent free process. Optimum condition of solvent process using 2-methyl-2-propanol were : moral ratio of methyl glycoside to fatty acid 1:3: initial concentration of methyl glycoside 50g/l:enzyme(immodilized lipase Novozym 435 from Candidia antarctica) content 1%(w/v) : desiccant content 9%(w/v); reaction temperature $60^{\circ}C$: reaction time 10hrs. The yield of 99% was obtained. Solvent-free process was carried out in total absence of solvent at $70^{\circ}C$ under reduced pressure, 5-20mmHg. To give meximum yield of 99% at the optimum condition of molar ratio of methyl glycoside to fatty acid 1:3, enzyme content 10%(w/w), and reaction time 10hrs. The glycosylation reactivity of different glycosylation agents were sequent to $Methyl-{\beta}-D-fructofuranoside$. $Methyl-{\beta}-D-glucopyranoside$. $Methyl-{\beta}-D-fructofuranosi$ de, and $Methyl-{\alpha}-D-glucopyranoside$.