• Bulletin of the Korean Chemical Society
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• 제18권1호
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• pp.18-23
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• 1997

Data from structure/activity studies in vir gene induction system have led to evaluate the working hypothesis of interaction between phenolic inducers and phenol binding proteins. The primary specificity in the association of a phenolic inducer with its receptor in our system is hypothesized to be the hydrogen bonding interactions through the ortho methoxy substituents as well as the proton transfer between the inducer and the binding protein. In this paper the proposed working model for phenol-mediating signal transduction was evaluated in several ways. The importance of the general acid-base catalysis was first addressed by the presence of an acidic residue and a basic residue in the phenol binding protein. Series of compounds were tested for vir gene expression activity to confirm the generation of a strong nucleophile by an acidic residue and an involvement of a basic residue as a proton acceptor. An attempt was made to correlate the pKa values of the phenolic compounds with vir gene induction activities as inducers to further support the proposed proton transfer mechanism. Finally, it was also observed that the regioselectively attached methoxy group on phenol compounds is required as the proper hydrogen bond acceptor.

• Asian-Australasian Journal of Animal Sciences
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• 제24권12호
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• pp.1744-1751
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• 2011

This study was conducted to compare the effects of feeding dry or fermented (aerobically or anaerobically with or without lactic acid bacteria) restaurant food residue mixture-containing diets on animal performance and blood profiles. Rats were used as the model animal for the simulation of laboratory rodents, rabbit or horse feeding and fed for 4 wks. The results were compared with feeding a dry diet (control) with the same ingredient composition as diets processed by aerobic and anaerobic methods. Feeding all the fermented diets tended to increase (p>0.05) average daily gain of rats resulting in improved (p<0.01) feed efficiency. Apparent digestibility of NDF was increased (p<0.05) by feeding the fermented diets, although digestibilities of DM, OM, CP, and NFC were not affected (p>0.05). Compared with the aerobically fermented diet, digestibility of ADF was increased (p<0.05) for the anaerobically fermented diet and for the 0.5% LAB culture plus anaerobically fermented diet. The digestibility of crude ash tended to increase (p>0.05) with feeding of the fermented diets. Feeding either of the fermented diets had little effects on serum nutrients, electrolytes, enzymes and blood cell profiles of rats except sodium and uric acid concentrations. These results showed that compared with feeding a dry food residue-containing diet, feeding aerobically or anaerobically fermented diets showed better animal performance as indicated by higher feed efficiency and rat growth rate. These improvements were attributed to the desirable dietary protein conservation during the food residue fermentation process and to higher total tract digestibilities of NDF and crude ash in the fermented food residue diets.

• 에너지공학
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• 제14권4호
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• pp.268-276
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• 2005

액체연료(중유)공급량 기준 20kg/hr규모의 반응로에서 증기분무 내부 혼합식 노즐을 이용하여 잔사유의 연소실험을 수행하였다. 본 실험에서 사용한 감압 잔사유는 점도가 높고 황함량, 잔류탄소와 금속성분의 함량도 높았다. 잔사유의 착화를 위해서는 반응로를 일정온도까지 예열하여야 했으며 이는 LPG를 이용하였다. 잔사유 공급량을 변화시키면서 축방향 및 반경방향의 로내 가스 온도, 주요 가스농도 및 채집된 고체 입자를 분석하였다. 잔사유의 주반응영역은 버너 팁으로부터 약 1 m 근방에서 형성되었으며 이는 축방향 가스 온도, 농도 분포 및 입자의 크기로부터 확인할 수 있었고, 반응로의 하류에서는 완전 확립된 온도분포를 보여주고 있었다. 고체 입자의 SEM 분석으로부터 잔류 탄소입자는 기공이 많은 형태를 띠고 있었다.

• Journal of Applied Biological Chemistry
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• 제60권2호
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• pp.95-100
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• 2017

오미자를 착즙하고 남은 착즙박을 이용하여 추출조건에 따른 이화학적 변화를 알아보았다. 즉, 착즙박을 열수, 50% 에탄올, 70% 에탄올 및 95% 에탄올을 추출 용매로 사용하였으며, 추출시간은 1시간에서 10시간까지 1시간 간격으로 $60^{\circ}C$에서 정치 추출하여 여과한 후, 감압 농축하여 제조된 용매별 농축액을 분석시료로 이용하였다. 오미자에 함유된 유효성분 중 하나인 schizandrin 함량은 추출 용매에 따라서 열수: 0.52 g/100 g, 50% 에탄올: 1.79 g/100 g, 70% 에탄올: 2.01 g/100 g 및 95% 에탄올은 2.37 g/100을 나타내었으며, 열수를 이용하여 추출한 경우보다 에탄올 농도가 증가할수록 schizandrin 함량이 증가하는 경향을 나타내었다. 총 폴리페놀 함량은 50% 에탄올 용매 추출물에서 16.70 mg/mL로 가장 높게 나타났으며, 2,2-diphenyl-1-picrylhydrazyl 전자공여소거능에 대한 효과는 분석 시료의 200 mg/mL 농도에서 측정하였을 때, 50% 에탄올 용매 추출물에서 86.16%로 가장 높게 나타내었다. 또한, 안토시아닌 함량은 모든 용매 추출물이 추출 시간이 증가할수록 감소하는 경향을 보였다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1999년도 무주 반딧불 축제 기념 세미나
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• pp.21-38
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• 1999

제초제는 현대 농업에서 필수적인 농자재이나 생리활성을 갖기에 비목적대상생물에 대한 위해성을 배제할 수 없다. 제초제의 문제점중 잔류문제는 가장 중요한 부분이며 그중 인간생활과 밀접한 관계를 갖는 토양, 농작물중의 잔류는 더욱 중요하다. 토양과 통작물중 제초제의 잔류유해성은 토양, 기상, 제초제의 사용 및 작물재배 등의 조건에 따라 현저히 변화되나, 현 시점에서 토양중 제초제의 잔류에 대한 문제점은 후작물에 대한 영향과 같은 국부적인 것을 제외하고는 거의 없으며 농작물중 난류 또한 큰 문제가 없는 것으로 사료된다. 그러나 국민건강, 토양생태계를 비롯 환경에 대한 더 높은 안전성 확보를 위하여 제초제에 대한 모니터링실험과 같은 잔류성 조사가 더 많이 요구되며 사용자는 안전사용기준을 준수해야 하겠으며 제초제개발측면에서는 보다 저독성 약제를 개발하는데 최선을 다해야 하겠다.

• 공업화학
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• 제8권4호
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• pp.610-616
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• 1997

낙동강에서 채취한 남조류 Microcystis로부터 간독성물질이자 protein phosphatase 1과 2A의 강력한 억제제인 microcystin-LR과 microcystin-RR을 분리하였다. 이들 물질의 독성과 구조와의 관계들을 알아보기 위하여 몇가지 유도체들을 합성하여 독성실험을 하였다. Glu와 MeAsp의 카르복실기를 에스테르화할 경우 독성을 잃어버리는 것을 알 수 있었다. 반면에 Mdha 잔기의 이중결합을 $NaBH_4$로 환원하여 Ala잔기로 전환한 경우에는 독성을 그대로 유지하였고 또한 microcystin-LR의 Arg잔기의 guanidyl기를 dimethylpyrimidyl기로 변환한 경우에도 독성에는 크게 영향을 주지 않는 것을 알 수 있었다. 따라서 2개의 카르복실기는 microcystin이 독성을 나타내는데 아주 중요한 역할을 하는 반면에, Mdha 및 Arg잔기의 존재는 큰 역할을 하지 않는 것으로 여겨진다.

• 반도체디스플레이기술학회지
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• 제16권1호
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• pp.22-28
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• 2017

The result of stripping process for the removal of the post etch/ash Photoresist (PR) residue on an aluminum patterned wafer by using supercritical $CO_2$ ($sc-CO_2$) mixture, was investigated by scanning of electron microscope (SEM) inspection of wafer, measuring the cloud points and visual observation of the state of $sc-CO_2$ mixtures. It was found that $sc-CO_2$ mixtures were made by mixing additives and $sc-CO_2$ should form homogeneous and transparent phase (HTP) in order to effectively and uniformly remove the post etch/ash PR residue on the aluminum patterned wafer using them. The additives were formulated by mixing and co-solvents like an amine compound and fluorosurfactants used as HTP agents, and the PR residue on the wafer were able to be rapidly and effectively removed using the $sc-CO_2$ mixture of HTP. The five kinds of additives were formulated by the recipe of mixing co-solvents and surfactants, which were able to remove PR residue on the wafer by mixing with $sc-CO_2$ at the stripping temperature range from 40 to $80^{\circ}C$. The five kinds of $sc-CO_2$ mixtures which were named as PR removers were made, which were able to form HTP within the above described stripping temperature. The cloud points of $sc-CO_2$ mixtures were measured to find correlation between them and HTP.

• 한국식품과학회지
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• 제11권1호
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• pp.18-25
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• 1979

BHC를 살포하여 재배한 현미(玄米)(BHC잔류량 0.3 ppm)의 도정(搗精), 세미(洗米), 및 취반(炊飯)중 BHC 잔류량(殘留量)을 분석하여 그의 행방을 추적한 결과는 다음과 같다. 1) 현미의 도정(搗精)중 BHC는 10분도미에서 8%, 7분도미에서 20%가 잔류하였다. 2) 쌀의 세척(洗滌)중 10분도미에서는 34%, 7분도미에서는 31%가 잔류하였다. 3) 재래식 취반(炊飯)과 전기밥솥에 의한 취반중 10분도미에서는 각각 86%, 77%, 7분도미에서는 각각 69%, 41%가 잔류하였다. 4) 전체적으로 보아 현미로부터 밥으로의 BHC 이행률(移行率)은 10분도미에서 2.3%, 7분도미에서 4.3%에 불과하였다. 따라서 현미의 조리(調理), 가공(加工)중 발생되는 BHC의 제거량(除去量)을 잔류농약 허용량(許容量)설정에 반영(反映)하여 야 될 것이다.

• 한국작물학회지
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• 제47권2호
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• pp.137-141
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• 2002

Decomposition of green manure is necessary for the nutrient supply in farm soil. Hairy vetch as a green manure is superior to other winter legumes in terms of wintering ability and N accumulation. This experiment was carried out to investigate the decomposition and N release of hairy vetch and its effect on rice production as the following crop in paddy field. Decomposition of hairy vetch placed by soil depth of 0, 10 and 20cm at transplanting time was investigated by mesh bag method, which was enclosed chopped residue in mesh bags. The fate of $^{15}$ N derived from $^{15}$ N-labeled hairy vetch was investigated at harvest in three levels of N fertilization. Grain yield of the transplanted paddy rice cultured with hairy vetch as starter N were compared with that of applying urea as starter N in the field. Hairy vetch residue decomposed very rapidly both in transplanted and dry-seeded paddy field. In transplanted paddy field, hairy vetch residue lost 72-81 % and 86-90% of its weight after one and five month, respectively, as affected by incorporation depth. The C/N ratio of the decomposing vetch residue increased sharply during the early stages and after then, decreased slowly. The amounts of N and P released from the vetch were about 90% and 97% of initial content after one month, respectively. Recoveries of hairy vetch-$^{15}$ N by rice plant were 30.6, 34.6 and 35.7% in 0, 6 and 12 kg urea-N 10 $a^{-l}$ application, respectively, indicating that N fertilization increased the recovery of hairy vetch. $^{15}$ N. Hairy vetch residue incorporated as starter maintained significant N $H_4$$^{+}$-N concentration in soil water of plow layer until effective tillering stage. Grain yield in the plot applied with hairy vetch was not significantly different from that in the plot with urea. We concluded that hairy vetch incorporation could substitute starter N fertilization and showed possibility to reduce N amount of top-dressing.g.g.

• 한국환경농학회지
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• 제30권4호
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• pp.357-366
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• 2011

BACKGROUND: Mathematical model such as GLEAMS have been developed and successfully applied to upland fields to estimate the level of pesticide residues in soil. But, the GLEAMS model rarely applied to the Korean conditions. METHODS AND RESULTS: To evaluate pesticide transport in soil residue using the GLEAMS model from pepper plot, Alachlor, Endosulfan, Cypermethrin and Fenvalerate were applied for standard and double rate. Soil sampling was conducted and decaying patterns of pesticides were investigated. Observed climate data such as temperature and irrigation amount were used for hydrology simulation. The observed pesticide residue data of 2008 were used for parameter calibration, and validation of GLEAMS model was conducted with observed data of 2009. After calibration, the $K_{oc}$ (Organic carbon distribution coefficient) and WSHFRC (Washoff fraction) parameters were identified as key parameters. The simulated concentrations of the pesticides except Fenvalerate were sensitive to $K_{oc}$ parameter. Overall, soil residue concentrations of Alachlor, Cypermethrin and Fenvalerate were fairly simulated compared to those of Endosulfan. The applicability of the GLEAMS model was also confirmed by statistical analysis. CONCLUSION(s): GLEAMS model was eligible for evaluation of pesticide soil residue for Alachlor, Cypermethrin and Fenvalerate.