• Title/Summary/Keyword: chemical components

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Study of Smoking Component Distribution and the Relation between Chemical Components and Physical Characteristics of Cigarettes (제품담배 연기성분 분포 특성 조사 및 물리적 특성과의 관련성 구명)

  • 황건중;이영택
    • Journal of the Korean Society of Tobacco Science
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    • v.23 no.2
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    • pp.179-184
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    • 2001
  • This study was conducted to determine the smoke component distribution and the relationship between chemical components and physical characteristics of cigarettes. 16 different cigarette brands which were sold in the market were selected for this study. Five kinds of smoke components which have been tar, nicotine, water, carbon monoxide(CO) puff No., and six kinds of physical characteristics which were filter type, leaf weight, filter weight, UPD, EPD, dilution rate were analyzed. The average values in tar, nicotine, water, CO concentration were 6.5 mg/cig. 0.66 mg/cig, 1.12 mg/cig. and 6.32 mg/cig., respectively. The average ratios of nicotine/tar and CO/tar were 0.10, and 1.02 respectively. The distribution of smoke components collected in the cambridge filter and cigarette filter was different. The averages of tar and nicotine removal efficiency by a cigarette filter were 53%, and 48%, respectively. All smoking components were positively correlated with other smoking components. filter types, EPD, and dilution rate were showed high correlation to the changes of smoke components. Especially, dilution rate of cigarette strongly affected on the changes of all smoke components.

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Rheology and morphology of concentrated immiscible polymer blends

  • Mewis, Jan;Jansseune, Thomas;Moldenaers, Paula
    • Korea-Australia Rheology Journal
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    • v.13 no.4
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    • pp.189-196
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    • 2001
  • The phase morphology is an important factor in the rheology of immiscible polymer blends. Through its size and shape, the interface between the two phases determines how the components and the interface itself will contribute to the global stresses. Rheological measurements have been used successfully in the past to probe the morphological changes in model blends, particularly for dilute systems. For more concentrated blends only a limited amount of systematic rheological data is available. Here, viscosities and first normal stress differences are presented for a system with nearly Newtonian components, the whole concentration range is covered. The constituent polymers are PDMS and PIB, their viscosity ratio can be changed by varying the temperature. The data reported here have been obtained at 287 K where the viscosities of the two components are identical. By means of relaxation experiments the measured stresses are decomposed into component and interfacial contributions. The concentration dependence is quite different for the two types of contribution. Except for the component contributions to the shear stresses there is no clear indication of the phase inversion. Plotting either the interfacial shear or normal stresses as a function of composition produces in some cases two maxima. The relaxation times of these stresses display a similar concentration dependence. Although the components have the same viscosity, the stress-component curves are not symmetrical with respect to the 50/50 blend. A slight elasticity of one of the components seems to be the cause of this effect. The data for the more concentrated blends at higher shear rates are associated with a fibrillar morphology.

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Evaluation of Chemical Composition in Reconstituted Tobacco Leaf using Near Infrared Spectroscopy (근적외선 분광분석법을 이용한 판상엽 화학성분 평가)

  • Han, Young-Rim;Han, Jungho;Lee, Ho-Geon;Jeh, Byong-Kwon;Kang, Kwang-Won;Lee, Ki-Yaul;Eo, Seong-Je
    • Journal of the Korean Society of Tobacco Science
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    • v.35 no.1
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    • pp.1-6
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    • 2013
  • Near InfraRed Spectroscopy(NIRS) is a quick and accurate analytical method to measure multiple components in tobacco manufacturing process. This study was carried out to develop calibration equation of near infrared spectroscopy for the prediction of the amount of chemical components and hot water solubles(HWS) of reconstituted tobacco leaf. Calibration samples of reconstituted tobacco leaf were collected from every lot produced during one year. The calibration equation was formulated as modified partial least square regression method (MPLS) by analyzing laboratory actual values and mathematically pre-treated spectra. The accuracy of the acquired equation was confirmed with the standard error of prediction(SEP) of chemical components in reconstituted tobacco leaf samples, indicated as coefficient of determination($R^2$) and prediction error of sample unacquainted, followed by the verification of model equation of laboratory actual values and these predicted results. As a result of monitoring, the standard error of prediction(SEP) were 0.25 % for total sugar, 0.03 % for nicotine, 0.03 % for chlorine, 0.16 % for nitrate, and 0.38 % for hot water solubles. The coefficient of determination($R^2$) were 0.98 for total sugar, 0.97 for nicotine, 0.96 for chlorine, 0.98 for nitrate and 0.92 for hot water solubles. Therefore, the NIRS calibration equation can be applicable and reliable for determination of chemical components of reconstituted tobacco leaf, and NIRS analytical method could be used as a rapid and accurate quality control method.

Characterization of Fluxing and Hybrid Underfills with Micro-encapsulated Catalyst for Long Pot Life

  • Eom, Yong-Sung;Son, Ji-Hye;Jang, Keon-Soo;Lee, Hak-Sun;Bae, Hyun-Cheol;Choi, Kwang-Seong;Choi, Heung-Soap
    • ETRI Journal
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    • v.36 no.3
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    • pp.343-351
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    • 2014
  • For the fine-pitch application of flip-chip bonding with semiconductor packaging, fluxing and hybrid underfills were developed. A micro-encapsulated catalyst was adopted to control the chemical reaction at room and processing temperatures. From the experiments with a differential scanning calorimetry and viscometer, the chemical reaction and viscosity changes were quantitatively characterized, and the optimum type and amount of micro-encapsulated catalyst were determined to obtain the best pot life from a commercial viewpoint. It is expected that fluxing and hybrid underfills will be applied to fine-pitch flip-chip bonding processes and be highly reliable.

Evaluation of 1/f Noise Characteristics for Si-Based Infrared Detection Materials

  • Ryu, Ho-Jun;Kwon, Se-In;Cheon, Sang-Hoon;Cho, Seong-Mok;Yang, Woo-Seok;Choi, Chang-Auck
    • ETRI Journal
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    • v.31 no.6
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    • pp.703-708
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    • 2009
  • Silicon antimony films are studied as resistors for uncooled microbolometers. We present the fabrication of silicon films and their alloy films using sputtering and plasma-enhanced chemical vapor deposition. The sputtered silicon antimony films show a low 1/f noise level compared to plasma-enhanced chemical vapor deposition (PECVD)-deposited amorphous silicon due to their very fine nanostructure. Material parameter K is controlled using the sputtering conditions to obtain a low 1/f noise. The calculation for specific detectivity assuming similar properties of silicon antimony and PECVD amorphous silicon shows that silicon antimony film demonstrates an outstanding value compared with PECVD Si film.

Adsorption Characteristics of Endo Ⅱ and Exo Ⅱ Purified from Trichoderma viride on Microcrystalline Celluloses with Different Surface Area

  • 김동원;정영규;장영훈;이재국
    • Bulletin of the Korean Chemical Society
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    • v.16 no.6
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    • pp.498-503
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    • 1995
  • The adsorption behaviors of two major components purified, endo Ⅱ and exo Ⅱ, from Trichoderma viride were investigated using microcrystalline cellulose with different specific surface area as substrates. Adsorption was found to apparently obey the Langmuir isotherm and the thermodynamic parameters, ΔH, ΔS, and ΔG, were calculated from adsorption equilibrium constant,K. The adsorption process was found to be endothermic and an adsorption entropy-controlled reaction. The amount of adsorption of cellulase components increased with specific surface area and decreased with temperature and varied with a change in composition of the cellulase components. The maximum synergistic degradation occurred at the specific weight ratio of the cellulase components at which the maximum affinity of cellulase components obtains. The adsorption entropy and enthalpy for respective enzyme system increased with specific surface area increase. The adsorption entropy was shown to have a larger value with enzyme mixture.

Observations of Boring Behaviour and the Drilling Mechanism of Lunatia fortunei (Gastropoda: Naticidae) in Western Korea

  • Chung, Ee-Yung;Kim, Sung-Han;Back, Yong-Hae
    • The Korean Journal of Malacology
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    • v.27 no.3
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    • pp.253-259
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    • 2011
  • Boring behaviour and drilling mechanism were investigated by visual observations. In this study, of two kinds of holes (the outer and inner holes) which are formed by drilling of boring gastropod Lunatia fortunei (Naticidae), the diameters of the outer holes are broader and larger than those of the inner holes, and their holes look like the crater in shape, as seen in all valves of bivalves bored by Naticidae species. Two kinds of glands (the accessory boring gland and accessory salivary gland) on the foots of boring gastropods have been investigated. Of them, it has been confirmed that only the accessory salivary glands on the foots secreted sulphuric (acidic) components in the mucus (secretion), while the accessory boring glands on the foots did not secrete their components. In this study, we confirmed that L. fortunei possess the accessory boring gland on the foot, as seen in most species in Naticidae. Accoeding to the results of the experiment of the blue litmus paper tests of the mucus (secretions) secreted from the accessory boring gland the color of the blue litmus paper did not turn red in color because chemical components of mucus (secretion) secreted from the accessory boring gland on the foot of L. fortunei (boring gastropod) were not acidic components. It is supposed that the mucus, which is secreted from the accessory boring gland, contained gelatin-like substances or enzymes without acidic components, as already reported in Naticidae species. Therefore, these substances may be involved in softening the surface of the valves of M. veneriformis. Consequently, it is assumed thar L. fortunei bores holes through the shells of molluscs by means of following 3 methods: (1) a softening of the calcareous shells of M. veneriformis with chemical secretions (including gellatin-like substances or enzyme except for acidic components) from the accessory boring glands, (2) mechanical rasping with the radula, (3) a combination of both. In this study, particularly, acidic components, which are involved in softening the surface of the shells, are not associated with the boring mechanism of L. fortunei because chemical acidic components were not detected in the mucus (secretion), as found in Naticidae species.

The Research of New Azo Red Pigments for Textile Printing (섬유날염용 신규 아조 적색안료 연구)

  • O, Se-Hwa;Sin, Seung-Rim;Kim, Yeong-Seok;Heo, Seon-Hui;Kim, Sun-Il;Sin, Jong-Il
    • Proceedings of the Korean Society of Dyers and Finishers Conference
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    • 2004.04a
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    • pp.199-203
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    • 2004
  • The azo red pigments for textile printing containing amino-N-substituted benzamide derivatives as diazo components and 2-hydroxy-3-naphthoyl derivatives as coupling components were prepared. They have been printed on cotton, and the fastness, such as light, washing, dry cleaning, rubbing and heat stability was estimated. The new azo red pigments were valuable colorants in case of textile printing.

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