• Title/Summary/Keyword: 저독성

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Low NOx Combustors in a Industrial Gas Turbine (산업용 가스터빈의 저NOx 연소기)

  • 신동신
    • Journal of the KSME
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    • v.34 no.12
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    • pp.929-939
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    • 1994
  • 최근 환경문제와 관련하여 정제된 석유 연료가 아닌 천연가스와 같은 연료의 사용이 증가하면서 산업용 가스터빈의 연소기술에 대한 관심이 집중되고 있다. 가스터빈 연소로 생성되는, 환경을 위협하는 오염물은 연기, 수증기, 일산화탄소(CO), 미연 탄화수소, $NO_{x}$, $SO_{x}$ 등이 있다. 수증기 및 일산화탄소는 지구 온실화에 영향을 미치고 있으나 그다지 심각한 정도는 아 니며, $SO_{x}$는 독성이 있으나 연료 정제시 제거되어질 수 있다. $NO_{x}$는 지구의 오 존층을 파괴하여 생태계를 위협하기 때문에 오염 배출물중 가장 심각하게 고려되어지고 있다. 미국에서는 법으로 산업용 가스터빈의 $NO_{x}$의 양을 규제하고 있는데 15% 산소배출농도에 대하여 1984년에 75ppm에서 1993년에 30ppm으로 낮추어 규제하고 있다. 일본도 미국과 비슷한 수준으로 규제하고 있으며, 따라서 최근의 가스터빈 연소기술은 저 $NO_{x}$연소기에 대한 것으로 저$NO_{x}$연소에 관한 개론 및 가스터빈 연소기의 저$NO_{x}$화 방법, 그리고 미 국과 일본의 최근의 저$NO_{x}$연소기 개발동향에 대하여 다루고자 한다.

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Anti-mold Effectiveness of Neonicochid Type Wood Preservative (네오니코치드계 목재보존제의 방곰팡이 효력)

  • Lee, Dong Heub;Lee, Jong Shin
    • Journal of the Korean Wood Science and Technology
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    • v.42 no.1
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    • pp.41-48
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    • 2014
  • To development of the low toxic preservatives, we prepared 29 kinds of chemicals using dinotefuran of low toxic insecticide, IPBC and propiconazol of fungicide, and clove oil has fungicidal activity, but is harmless to humans. It was conducted to investigate the inhibitory effectiveness of mycelial growth and anti-mold effectiveness to treated PDA medium and wood specimen with prepared chemicals. It was not showed anti-mold effectiveness that solvent and emulsifier form preservatives. Therefor, we thought that only four component, dinotefuran, IPBC, propiconazol and clove oil, has anti-mold effectiveness. In the PDA medium test, the preservative which has much IPBC showed high anti-mold effectiveness. By the wood specimen test, it was known that many prepared preservatives which showed good inhibitory effectiveness of mycelial growth in the PDA medium test, have not anti-mold effectiveness. Of all prepared preservatives in this study, only three preservatives containing dinotefuran and IPBC, or adding clove oil appeared the excellent anti-mold effectiveness.

Integrated Pollinator-Pest Management (IPPM) Strategy as Future Apple IPM (사과 IPM 미래 전망: 화분매개자 친화형 병해충 종합관리 (IPPM) 전략)

  • Jung, Chuleui
    • Korean journal of applied entomology
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    • v.60 no.1
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    • pp.145-154
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    • 2021
  • Integrated pest management system in Korean apple has significantly advanced for last few decades. However harmful effects of pesticides threats the ecosystem services of natural enemies and pollinators. Apple require cross-pollination and Insect pollination with diversity and abundance is one of the keys to profitable apple production in quantity and quality as well. Thus crop protection tools are to be administered in harmony to meet the pest suppression and protection of beneficial organisms such as natural enemies and pollinators. Adding onto the established IPM system, integrated pollinator-pest management (IPPM) concept is proposed as the future direction of apple IPM. For this, ecological enginnering of creating habitats for pollinators, landscape management and agroecosytem diversification as well as selective soft pesticide uses on time guided by pest monitoring and phenologyand targeted delivery are further proposed. Recent shift of agroecosystem from climate change and new pest outbreaks require new paradigm of pest management for sustainable agricultural production.

Acute Oral Toxicity of Chitooligosaccharides in Mice (Chitooligosaccharides의 마우스에 대한 급성 경구독성)

  • 박헌국
    • The Korean Journal of Food And Nutrition
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    • v.16 no.4
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    • pp.437-443
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    • 2003
  • Chitooligosaccharides were prepared by enzymatic hydrolyzing of crab shell chitosan. Low molecular weight chitooligosaccharides(LMW-chitooligosaccharides), 64.3% of which was composed of trimer, tetramer, and pentamer, was obtained by hydrolyzing chitosan with the chitosanase originated Bacillus pumilus BN-262. High molecular weight chitooligosaccharides(HMW-chitooligosaccharides), 49.3% of which was composed of chitooligosaccharides over heptamer, was obtained by hydrolyzing chitosan with the cellulase originated Trichoderma viride. Acute oral toxicity of chitooligosaccharides were tested in mice. Chitooligosaccharides did not have any toxic effect in mice and oral LD$\_$50/ value of chitooligosaccharides was over 5.0g/kg in mice.

Toxic Effects of Phenol on Survival and Oxygen Consumption of the Abalone Juvenile, Haliotis discus hannai (참전복, Haliotis discus hannai 치패의 생존과 산소소비에 미치는 phenol의 독성 영향)

  • KIM Heung-Yun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.3
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    • pp.496-504
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    • 1997
  • This study was carried out to estimate toxic effects of phenol on survival and metabolism of the abalone juvenile, Haliotis discus hannai. The experiment was conducted by renewal bioassay procedure with different salinities at $20^{\circ}C$. The $LC_{50}$ of the juvenile exposed to phenol in the range of 0.5 and $100mg/\ell\;was\;34.3\~6.5mg/\ell\;at\;2.4\%_{\circ}\;and\;52.2\~9.3m/\ell\;at\;32\%_{\circ}$ salinity with exposure time from 24 hours to 96 hours. $LT_{50}$ was remarkablely reduced with increase of phenol conentration and decrease of salinity. Lethal toxicity or phenol was higher at low salinity than at high salinity. Therefore, salinity is likely to be one of factor to increase phenol toxicity. The oxygen consumption of the juvenile was reduced with increase of phenol concentration and with decrease of salinity. In spite of phenol toxicity, the oxygen consumption of the juvenile exposed to phenol of low concentration was high and similar as compared with that of control group. Survival rates of the abalone kept in phenol-free sea water after exposure to phenol concentration of 5, 10 and $20mg/\ell$ for 96 hours were reduced with decrease of salinity. Durations required to recover the normal metabolic rate of the juvenile, which was exposed to phenol concentration of 5, 10 and $20mg/\ell$ for 96 hours, were made longer with increasing phenol concentration. In the case of the juvenile exposed to sublethal concentration of phenol for 15 days, it were elongated as compared with that of the abalone exposed to phenol concentration caused acute toxicity. The result of this experiment indicated that relatively low concentration of phenol can impact on the abalone juvenile in marine ecosystem.

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A Study on the Treatment of Canine Demodicidosis with Low Toxic Organ Phosphates (저독성유기인제에 의한 견모낭충증치료의 실험적연구)

  • Seong Jae Gi
    • Journal of the korean veterinary medical association
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    • v.6 no.1
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    • pp.26-35
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    • 1962
  • A Study on the Treatment of Canine Demodicidosis with Low Toxic Organ Phosphates In this experiment, the treatment of canine demodicidosis with Dipterex(50$\%$ Diethyl trichlorohydroxethyl phosphanate), a kind of low toxic organic phosphates, h

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Polyacrylonitrile(PAN)/N-2-hydroxypropyltrimethylammonium chitosan chloride(HTCC) 블렌드 섬유의 제조와 물성

  • 남창우;김영호;고석원
    • Proceedings of the Korean Fiber Society Conference
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    • 1998.04a
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    • pp.40-44
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    • 1998
  • 키토산은 키틴을 탈아세틸화시켜 제조한 물질로서, 우수한 항미생물성, 생분해성, 비독성 및 강한 이온흡착능을 지니고 있어 이러한 우수한 성질을 섬유에 응용하기 위하여 저분자화하여 가교제로서 섬유에 부착시키는 방법[1], 섬유고분자와의 블렌딩[2,3] 등 여러 방법이 연구되어 왔으나 제조비용과 공정상의 단점 둥으로 사용에 제한이 따르고 있다.(중략)

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Selective Toxicity and Acetylcholinesterase Inhibition of Diazinon and Carbofuran to Killifish(Oryzias latipes) and Loach(Misgurnus anguillicaudatus) (Diazinon과 Carbofuran의 송사리(Oryzias latipes)와 미꾸리(Misqurnus anguillicaudatus)에 대한 선택적 독성과 Acetylcholinesterase저해)

  • Kim, Young-Bae;Lee, Sung-Kyu;Kim, Yong-Hwa;Roh, Jung-Koo
    • Korean Journal of Environmental Agriculture
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    • v.7 no.2
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    • pp.117-123
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    • 1988
  • This study was initiated to understand the mechanism of selective toxicity of diazinon and carbofuran to killifish and loach. Conventional LC50 was calculated from fish test. IC50 with acetylcholinesterase activity was estimated using whole body and wet brain homogenate of the two fish species. Acetylcholinesterase activity of killifish was approximately twice as high as that of loach. The selective toxicity of diazinon to killifish and loach was partly (14 : 4) explained by the IC50 of diazoxon, a toxic metabolite of diazinon. IC50 of carbofuran also partly (14 : 3.4) contributed to the selectivity. These result suggested that the enzymatic method might be utilized as a screening tool for the chemicals affecting fish species of environmental concern with certain limitations which should be overcome in future studies.

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