• 제목/요약/키워드: chemical components

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황색종 잎담배의 화학성분에 의한 관능 특성 예측 (Prediction of Sensory Property form Leaf Chemical Property in Flue-cured Tobacco)

  • 정기택;복진영;김시몽;이철희;이종률
    • 한국연초학회지
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    • 제29권2호
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    • pp.74-79
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    • 2007
  • This study was conducted to evaluate the prediction of sensory property of smoke from leaf chemical property and characterize leaf chemical components for the best tobacco taste's leaves in flue-cured tobacco. For analytical and sensory evaluations, one hundred and forty grades were used. The major leaf chemical components to predict the sensory property of smoke were nicotine for impact, irritation and off taste & odor, and total sugar/nicotine ratio for tobacco taste. Within ${\pm}20%$ range of difference, the predictable probabilities of sensory property of smoke form leaf chemical property were 80.0% for off taste & odor and $91.4{\sim}96.4%$ for impact, irritation and tobacco taste. As a result of K-means cluster analysis on the basis of tobacco taste, the desirable leaf chemical component contents were $2.77{\sim}3.55%$ in nicotine and $5.1{\sim}6.9$ in total sugar/nicotine ratio. This study suggest that the some regression equations may be useful to predict the sensory property of tobacco smoke from a few selected leaf chemical components in flue-cured tobacco and to select the flue-cured tobacco leaves for enhance the tobacco taste of cigarette.

2'-deoxyribonucleosides의 단일 및 다성분계의 비선형 흡착평형식 (Nonlinear Adsorption Isotherm of Single and Multi-Components of 2'-Deoxyribonucleosides)

  • 김룡매;한순구;최대기;노경호
    • Korean Chemical Engineering Research
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    • 제43권2호
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    • pp.230-235
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    • 2005
  • 2'-deoxyribonucleosides중에서 dUrd(2'-deoxyuridine), dGuo(2'-deoxyguanosine), dAdo(2'-deoxyadenosine)의 단일 및 다성분계의 흡착평형식을 동적방법으로 구하기 위해 물과 메탄올(90/10, vol%)을 이동상으로 하는 역상 액체 크로마토그래피를 사용하였다. 시료의 주입부피가 증가함에 따라서 체류시간이 짧아지고 피크가 삼각형 모양을 보여서, Langmuir 흡착평형식으로 가정하였다. PIM (pulsed-input method)에 의해서 Langmuir 흡착평형식의 매개변수를 구하고, 경쟁적인 다성분계의 흡착평형식을 사용하였다. 체류시간이 짧은 dUrd와 dGuo의 경우에서는 단일 및 다성분계에서 실험값과 계산값이 잘 일치하였지만, 가장 늦게 용출되는 dAdo에서는 비이상 비선형적인 특성으로 인해서 약간의 오차가 있었다.

THE USE OF NEAR INFRARED REFLECTANCE SPECTROSCOPY(NIRS) TO PREDICT CHEMICAL COMPOSITION ON MAIZE SILAGE

  • D.Cozzolino;Fassio, A.;Mieres, J.;Y.Acosta
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1610-1610
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    • 2001
  • Microbiological examination of silage is of little value in gauging the outcome of silage, and so chemical analysis is more reliable and meaningful indicator of quality. On the other hand chemical assessments of the principal fermentation products provide an unequivocal basis on which to judge quality. Livestock require energy, protein, minerals and vitamins from their food. While fresh forages provide these essential items, conserved forages on the other hand may be deficient in one or more of them. The aim of the conservation process is to preserve as many of the original nutrients as possible, particularly energy and protein components (Woolford, 1984). Silage fermentation is important to preservation of forage with respect of feeding value and animal performance. Chemical and bacteriological changes in the silo during the fermentation process can affect adversely nutrient yield and quality (Moe and Carr, 1984). Many of the important chemical components of silage must be assayed in fresh or by extraction of the fresh material, since drying either by heat or lyophilisation, volatilises components such as acids or nitrogenous components, or effects conversion to other compounds (Abrams et al., 1987). Maize silage dorms the basis of winter rations for the vast majority of dairy and beef cattle production in Uruguay. Since nutrient intake, particularly energy, from forages is influenced by both voluntary dry matter intake and digestibility; there is a need for a rapid technique for predicting these parameters in farm advisory systems. Near Infrared Reflectance Spectroscopy (NIRS) is increasingly used as a rapid, accurate method of evaluating chemical constituents in cereals and dried forages. For many years NIRS was applied to assess chemical composition in dry materials (Norris et al., 1976, Flinn et al., 1992; Murray, 1993, De Boever et al., 1996, De la Roza et al., 1998). The objectives of this study were (1) to determine the potential of NIRS to assess the chemical composition of dried maize samples and (2) to attempt calibrations on undried samples either for farm advisory systems or for animal nutrition research purposes in Uruguay. NIRS were used to assess the chemical composition of whole - plant maize silage samples (Zea mays, L). A representative population of samples (n = 350) covering a wide distribution in chemical characteristics were used. Samples were scanned at 2 nm intervals over the wavelength range 400-2500 nm in a NIRS 6500 (NIRSystems, Silver Spring, MD, USA) in reflectance mode. Cross validation was used to avoid overfitting of the equations. The optimum calibrations were selected on the basis of minimizing the standard error of cross validation (SECV). The calibration statistics were R$^2$ 0. 86 (SECV: 11.4), 0.90 (SECV: 5.7), 0.90 (SECV: 16.9) for dry matter (DM), crude protein (CP), acid detergent fiber (ADF) in g kg$\^$-1/ on dry matter, respectively for maize silage samples. This work demonstrates the potential of NIRS to analyse whole - maize silage in a wide range of chemical characteristics for both advisory farm and nutritive evaluation.

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왕초피나무의 성분연구(成分硏究) (A Study on the Chemical Components of Zanthoxylum coreanum Nakai(Rutaceae))

  • 김창민;허인옥
    • 생약학회지
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    • 제12권1호
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    • pp.5-11
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    • 1981
  • The five fractions from the barks of Zanthoxylum coreanum in Je-ju Island are examined in detail chromatographically in this paper. 37 compounds are detected in all of the fractions, and the compounds from each of fractions are found to be presumed that this plant is classified into the same group as that of the temperate Zanthoxylum taxa but is different from the tropical zanthoxylum taxa by its chemical components.

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잣버섯의 성분(成分) 연구(硏究)(I) (A Study on the Components of Lentinus lepideus Fr.(1))

  • 김성원
    • 한국균학회지
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    • 제7권1호
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    • pp.9-11
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    • 1979
  • The carpophores of Lentinus lepideus Fr. which grows wildly in Korea were collected in Gyeong Gi Province to examine the chemical components of the fungus. They were extracted with a mixture of chloroform and methanol. From the extract four spots were detected by TLC. One of these spots was identified as ergosterol by TLC, GLC and chemical tests.

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活性白土에 關한 硏究(제II報) 酸性白土의 構造 推定에 關하여 (Activated Clay Maunfacturing Studies(II) Studies on the Estimation of Acid Clay Structure)

  • 손선관;고명원
    • 대한화학회지
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    • 제14권4호
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    • pp.309-319
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    • 1970
  • Composition of Acid Clay, the raw material for activated clay manufacturing, was investigated to develop useful data in deciding activation condition. Speculations on components and structure of activated clay were also made in order to see how included components of raw materials change during activation process. And a study was made on relations between structure of activated its adsorptivity. For this research, theremogravimetric analysis, X-ray differaction analysis and calculation of adsorptive index were carried out.

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Ultrasonic Pretreatment for Thermophilic Aerobic Digestion in Industrial Waste Activated Sludge Treatment

  • Kim, Young-Kee;Kwak, Myung-Shin;Lee, Won-Hong;Park, Jeong-Woo
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제5권6호
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    • pp.469-474
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    • 2000
  • In order to enhance the degradation efficiency of waste activated sludge (WAS) by thermophilic aerobic digestion, an ultrasonic pretreatment was examined. It was observed that ultrasonic pretreatment increased the solubilization of organic matter in the WAS and that the solubilization ratio of the organics increased during the first 30 min but did not extensively increase thereafter. Therefore, a pretreatment time of 30 min was determined to be the economical pretreatment time from the experimental results. From the digestion experiments, which was conducted using the WAS collected from an oil refinery plant in Inchon, Korea, investigating the effects of an ultrasonic pretreatment on thermophilic aerobic digestion, it was confirmed that the proposed ultrasonic pretreatment was effective at enhancing the release of the cellular components in WAS and the degradation of released components in the thermophilic aerobic digestion.

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혼합 액체 연료의 화학반응 인자 계측에 관한 실험적 연구 (An Experimental Study on Measurement of Chemical Kinetic Parameters of a Liquid Fuel with Various Components)

  • 최효현;임준석;김철진;손채훈
    • 한국연소학회지
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    • 제16권3호
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    • pp.21-26
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    • 2011
  • Thermal analyses are conducted to measure chemical kinetic parameters of an unknown liquid fuel with various components. Thermal Analyses are divided into two different methods such as TGA(Thermo-Gravimetric Analysis) and DSC(Differential Scanning Calorimety). Non-isothermal experimental results are analyzed by adopting TGA and they are filtered by Freeman-Carroll method. As a results of the analysis, chemical parameters of the activation temperature and the reaction order are measured to be 6128.2 K and 1.4, respectively. Furthermore, the chemical kinetic parameters are obtained by a variety of mathematical processing methods. It has been found that they show a little difference depending on the processing method.