• 환경위생공학
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• 제15권3호
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• pp.70-74
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• 2000

The technology of malodorous substances treatment was classified physical separation and chemical destruction. This study was carried out to investigate the characteristics of malodorous substances treatment with the change of operating conditions from the ozone generator. The major results of this study were as follows : Removal efficiency by additive ozone rate was measured $NH_3$:95%(ozone additive rate : 2), $H_2S$ : 97%(ozone additive rate:4), $CH_3SH$ : 96%(ozone additive rate : 3), $(CH_3)_2S_2$ : 97%(ozone additive rate:5), $(CH_3)_3N$ : 95%(ozone additive rate : 1), $CH_3CHO$ : 95%(ozone additive rate : 2), $C_6H_5CHCH_2$ : 95%(ozone additive rate : 2).

• 생명과학회지
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• 제12권5호
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• pp.632-648
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• 2002

The term polyketide defines a class of natural products synthesized through the successive condensation of small arboxylic acids, which results in products containing multiple carbonyl or hydroxyl groups, each separated by one arbon atom, as in the structural element CH$_2$C(=0)CH$_2$CH(OE)CH$_2$C(=0)-. Plant flavonoids, fungal aflatoxins, as well as undreds of compounds of different structures that can inhibit the growth of bacteria, viruses, fungi, parasites or human umor cells are included in this diverse group. Some of antifungal polyketides also have immunosuppresive activity. olyketides can vary widely in structure, and the diversity of polyketide structures reflects the wide variety of their iological properties. This review focuses on the biosynthesis of polyketides and recent progress in combinatorial iosynthesis of new hybrid polyketide compounds.

• Journal of the Optical Society of Korea
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• 제5권1호
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• pp.16-19
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• 2001

A photopolymer, copoly (M4Ch-ChMA), copoly ((4-methacryloyloxy) chalcone-cholesteryl methacrylate), was synthesized in this study. The electro-optical (EO) characteristics for the photo-aligned vertical-alignment (VA)-liquid crystal display (LCD) were investigated. Excellent voltage-transmittance curves for the VA-LCD photo-aligned by polarized UV exposure on the copoly (M4Ch-ChMA) surface were observed. The response time for the photo-aligned VA-LCD decrease with increasing UV exposure time. consequently, the photo-dimerized chalcone moiety increased with increasing UV exposure time, which then contributed to a low response time for the VA-LCD photo-aligned.

• 대한화학회지
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• 제56권2호
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• pp.228-235
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• 2012

$N_2O_2$계 시프염기 리간드인 N,N'-bis(4-methoxysalicylidene)phenylendiamine(4-$CH_3O$-salphen)을 합성하였다. 합성한 4-$CH_3O$-salphen을 이용하여 분광광도법으로 수용액 중의 Cu(II)이온 정량실험을 시도하였다. Cu(II)이온 정량을 위한 최적 실험조건을 구한 결과, 4-$CH_3O$-salphen 농도는 $2.0{\times}10^{-4}\;mol/L$, 용매 DMSO와 물의 비율은 50/50(v/v), pH는 5.5에서, 온도는 $55^{\circ}C$에서 한 시간정도를 물중탕하고, 시료의 흡광도는 388 nm였고, 그 조건에서 검량곡선을 작성하였다. 작성된 검량곡선(${\varepsilon}=3.6{\times}10^4\;mol^{-1}cm^{-1}$)은 $R^2$=0.9963의 상관계수 값을 나타내었다. 이상의 최적화된 실험조건을 이용하여 온천수, 반도체 공장폐수 및 하수 처리장의 처리수를 채취하여 Cu(II)이온을 각각 정량 분석한 결과는 측정 평균값이 기준 값에 대하여 0.6~5.4% 범위에서 잘 일치 하였고, 정량한계는 31.77 ng/mL($5.0{\times}10^{-7}\;mol/L$)이었다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권4호
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• pp.478-482
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• 2000

Whole cassava (Manihot esculenta, Crantz) crop was harvested about 10-15 cm above ground at 3 months after planting and sun dried for 1-3 days or until the leaves were crispy-dried and the branches and stems were mostly wilted to produce cassava hay. Cassava hay (CH) contained 86.3% DM, 8.9% ash, 23.6% CP, 44.3% NDF, 30.0% ADF, 5.8% ADL, 0.257% condensed tannin and 0.35 mg % HCN, respectively. In addition, CH contained relatively higher amino acid than alfalfa hay especially methionine, isoleucine, leucine and lysine. Ruminal fermentation of CH resulted in high concentrations of $C_2$, $C_3$, and $C_4$ at 72, 17 and 7 mol/100 mole, respectively. A feeding trial was conducted to study on effect of feeding of cassava hay in late lactating dairy cows fed on urea-treated rice straw during the dry season on their intake, ruminal pH, $NH_3$-N, milk yield and compositions. Thirty, Holstein-Friesian crossbred cows in their first lactation were randomly assigned in a randomized complete block design to receive five different dietary treatments: T1=supplementation of concentrate to milk yield at 1:2, T2=supplementation of concentrate to milk yield at 1:2+0.56 kg DM, T3=supplementation of concentrate to milk yield at 1:3+1.3 kg DM CH, T4=supplementation of concentrate to milk yield at 1:4+1.70 kg DM CH, T5=CH fed on ad libitum+small concentrate supplement. All cows received urea-treated rice straw as a roughage source throughout a 80 d feeding trial. The experiment revealed that cassava hay contained high level of protein and minimal level of tannin at 3 months of harvest. Tannin intake ranged from 1.44 to 13.36 g/hd/d and did not affect on urea-treated rice straw intake. Milk yield across treatments were similar (5.4-6.3 kg/hd/d) (p>0.05) but 3.5% FCM was highest in cows received CH at 1.70 kg/hd/d. Feeding of cassava hay resulted in increasing milk fat (4.0 to 4.6%) (p<0.05) and milk protein (3.8 to 5.3%) (p<0.05). Moreover, the use of CH could reduce concentrate supplementation to milk yield from 1:2 to 1:4, respectively, thus resulted in more milk income return.

• Korean Chemical Engineering Research
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• 제46권5호
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• pp.1002-1007
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• 2008

이 논문의 목적은 PEMFC 작동을 위한 플라즈마 개질 시스템의 최적 조건을 연구한 것이다. 플라즈마 개질 반응기는 니켈 촉매 반응기와 동시에 사용하여 수소 생성을 증대하였다. 또한 수성가스 전환 반응기 및 선택적 산화 반응기는 연료전지의 촉매 피독에 영향을 주는 일산화탄소의 농도를 10 ppm 이하로 줄이기 위하여 제작되었다. 플라즈마 개질기에서 최대 수소생산 조건은 S/C 비 3.2, 메탄 2.0 L/min, 촉매반응기 온도는 $700{\pm}5^{\circ}C$ 그리고 입력전력 900 W이다. 이때의 합성가스의 농도는 $H_2$ 70.2%, CO 7.5%, $CO_2$ 16.2%, $CH_4$ 1.8% 이다. 수소 수율, 수소 선택도 그리고 메탄 전환율는 각각 56.8%, 38.1%, 92.2%이다. 에너지 효율과 에너지 요구량은 37.0%, 183.6 kJ/mol 이다. 추가적으로 $CO_2/CH_4$ 비 실험을 진행하였다. 또한 수성가스 전환 반응기는 플라즈마 개질 반응기의 최적조건으로 실험을 진행하였으며, 출구 농도는 $H_2$ 68.0%, CO 337 ppm, $CO_2$ 24.0%, $CH_4$ 2.2%, $C_2H_4$ 0.4%, $C_2H_6$ 4.1% 이다. 이때의 선택적 산화 반응기의 실험결과는 $H_2$ 51.9%, CO 0%, $CO_2$ 17.3%를 나타냈다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1997년도 한국재료학회 춘계학술발표회
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• pp.21-21
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• 1997

• Bulletin of the Korean Chemical Society
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• 제20권5호
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• pp.600-604
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• 1999

• 한국식품영양과학회지
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• 제25권1호
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• pp.163-169
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• 1996

인위돌연변이 유기에 의해 벼로부터 새로운 유전형질체를 개발하기 위하여 낙동벼(모품종)에서 고정된 엽록소 결핍계통(ch mutant)을 선발하였다. 이 계통은 생육 초기부터 엽록소결핍으로 정상엽에 비하여 노란색을 나타내기 때문에 엽록소의 광합성 관여 유전자탐색에 이용가능하다. ch mutant는 전 생육기간 동안 모품종의 51~87% 정도의 엽록소 함량을 보였으나 엽록소 a/b 함량비는 차이가 없었다. ch mutant의 총 엽록소 함량은 모품종의 70.2%였으면 anthocyanin 함량과 flavonol 함량은 각각 285%와 142% 로 높은 함량비를 나타냈다. ch mutant의 카로티노이드 함량은 모품종의 71.1%였고, 크산토필 함량은 56.6%였다. 특히 카로티노이드 성분중 lutein과 neoaxanthin 함량은 각각 모품종의 32%와 34.4%로 매우 낮았으며, $\beta$-카로틴은 차이가 없으나 antheraxsnthin 함량은 106.9%오히려 증가하였다. 개엽상태에서나 군락 상태에서 ch mutant의 반사율과 투과율은 모두 모품종에 비하여 높아 광흡수량은 저하되었다. ch mutant는 모품종에 비하여 출수기가 5일 늦고 간자, 수장, 주당수수, 수당 입수, 임실율, 천립 중 수량에 감소하였다. ch mu-tant와 모푸종은 esterase, phosphogluose isomerase, malic enzyme, hexokinase 동위 효소의 밴드 패턴에서 유의할 만한 차이를 나타내지 않았으나 엽록체 단백질의 경우 주요 밴드인 60KD의 분자량에서 차이를 보였다.

• 한국연소학회지
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• 제5권1호
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• pp.7-18
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• 2000

Numerical simulations of counterflow non-premixed $CH_4/C_2HCl_3/Air$ flames added 8%(by volume) C2HCl3 on the fuel side are conducted at atmospheric pressure using a detailed chemical reaction mechanism in order to understand the effect of strain rates. A detailed sensitivity analysis is also performed in order to assess the relative influence of each reaction on the flame established at a strain rate of 200s-1. The structure of flames (i.e., temperature, velocity, and concentration of species) established at both a strain rate of 150s-1 and 300s-1 are investigated. As the strain rate increases, the "flame zone" is restricted to a narrower range and the position of maximum temperature is shifted to the fuel side. The concentrations of major species, H2O, CO, H2, HCl, Cl2, and Cl are decreased with increased strain rate. The reaction involving chlorine, CH4 + Cl $\rightarrow$ CH3 + HCl, instead of the reaction, CH4 + H $\rightarrow$ CH3 + H2 influences the consumption of methane. C2HCl3 + OH $\rightarrow$ CHCl2 + CHOCl and HCl + OH $\rightarrow$ H2O + Cl, are major reactions, through which OH radicals are consumed.