• 제목/요약/키워드: Cd free

검색결과 336건 처리시간 0.027초

Recovery of Cholesterol from the $\beta$-Cyclodexgtrin-Cholestrerol Complex Using Immobilized Cyclomaltodextrinas of Alkalophilic Bacillus sp. KJ 133

  • Kwon, Ho-Jeong;Jung, Hye-Jin;Kwak, Hae-Soo
    • Journal of Microbiology and Biotechnology
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    • 제11권4호
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    • pp.712-715
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    • 2001
  • A new combined method including the enzymatic hydrolysis of $\beta$-cyclodextrin ($\beta$-CD) and solvent extraction fo cholesterol from the hydrolyzed mixture was developed to recover cholesterol from a $\beta$-CD-cholesterol complex prepared from dairy products, such as cream, milk, and cheese. Cyclomaltodextrinase (cyclomatodextrin dextrin hydrolase, EC 3.2.1.54, DCase_ prepared form alkalophilic Bacillus sp. KJ 133 hydrolyzed the $\beta$-DC of the $\beta$-CD-cholesterol complex, and then, free cholesterol was efficiently extracted from the hydrolyzed mixture by a nonpolar solvent such as ethyl acetate. To increase the stability of free CDase, immobilized CDase was developed using sodium alginate as a carrier. The immobilized CDase showed a high recovery yield of cholesterol in a time-dependent manner compared to the free CDase. A gas chromatography analysis showed that more than 70% of cholesterol was recovered from the $\beta$-DC-cholesterol complex of cream by the immobilized CDase, whereas only 3% and 29% of cholesterol were recovered when the solvent extraction and free CDase treatment were used, respectively. The cholesterol recovered can be used as a raw material for steroid synthesis. Furthermore, this method can be an efficient way to recover cholesterol or other organic compounds that are bound in a $\beta$ -DC-cholesterol or -organic compound complex.

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Growth of High Quality $Cd_{0.96} Zn_{0.04} Te$ Epilayers Used for an Far-infrared Sensor and Radiation Detector

  • Kim, B. J.
    • 한국공작기계학회논문집
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    • 제11권6호
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    • pp.111-117
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    • 2002
  • The high quality and a nearly stoichometric growth of $Cd_{1-y} Zn_y$/Te(y=0.04) epilayers have been successfully grown on GaAs substrate by hot wall epitaxy (HWE) by optimizing the growth condition including the preheating treatment and Cd reservoir temperature. The relationship between quality and thickness was examined and best value of FWHM from X-ray rocking curve of 121 arcsec are obtained. Also, emission peaks related to the recombination of free excitons such as the ground state and the first excited state were observed in the PL spectrum at 4.2K. The ($A^0$, X) emission related to Cd vacancy and deep level emission was not measured. These results indicated that the grown CZT/GaAs epilayer was high qualify and purity.

Characterization of Dye Decolorization in Cell-Free Culture Broth of Trametes versicolor CBR43

  • Ryu, Hyun;Ryu, Hee Wook;Cho, Kyung-Suk
    • Journal of Microbiology and Biotechnology
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    • 제27권1호
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    • pp.155-160
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    • 2017
  • The dye decolorization rate in a cell-free culture broth of the white-rot fungus Trametes versicolor CBR43 was studied, including the effects of inhibitors of NaCl, Zn(II), and Cd(II) on dye decolorization activity. The maximum rates of dye decolorization in cell-free culture broth were 1,410, 44.7, 41.2, and $0.19{\mu}mol{\cdot}l^{-1}{\cdot}min^{-1}$ for Acid Blue 62, Acid Black 175, Reactive Blue 4, and Acid Red 114, respectively. The inhibition effects of NaCl, Zn(II), and Cd(II) on dye decolorization were quantitatively compared using the half maximal inhibition concentration ($IC_{50}$), which indicates the concentration of an inhibitor required for 50% inhibition. Based on $IC_{50}$ values, dye decolorization in the cell-free culture broth of CBR43 was most potently inhibited by Cd(II), whereas the inhibitory effect of NaCl was relatively low. The dye decolorization rates and $IC_{50}$ data can be used in the design and development of a dye-wastewater treatment process using T. versicolor CBR43 and its operating factors.

HWE법에 의한 CdS 단결정 박막의 성장 (Growth of CdS Single Crystal Thin Films by HWE Method)

  • 양동익;최용대;김진배
    • 한국진공학회지
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    • 제1권3호
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    • pp.353-359
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    • 1992
  • 본 연구에서는 HWE 방법에 의하여 GaAs(100) 기판위에 입방정의 단결정 박막을 성장하였다. 성장된 CdS 단결정 박막의 결정구조와 방향을 ECP(electron channeling pattern)로 결정하였다. CdS 박막의 (400)면이 기판과 평행하게 성장됨을 알았다. CdS 박 막의 photoluminescence를 20K에서 측정하였는데, free exception, bound exception 및 donor-acceptor pair에 의한 발광이 관측되었다.

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(Na,K)$NbO_3$-CdO세라믹스의 전기적 특성 (Electrical properties of (Na,K)$NbO_3$-CdO ceramics)

  • 유영배;문병기;박종호;정수태
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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    • pp.204-205
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    • 2005
  • [ $(Na_{0.5},\;K_{0.5})NbO_3$ ] ceramics were studied as lead free Piezoelectric materials. The addition of CdO were enhanced the sinterability of the NKN ceramics. The $(Na_{0.5},\;K_{0.47}Cd_{0.02})NbO_3$ ceramics show that electromachanical coupling factor($k_p$) is 0.34and mechanical quality factor($O_m$) is 120.

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Microbial Colonization at Early Life Promotes the Development of Diet-Induced CD8αβ Intraepithelial T Cells

  • Jung, Jisun;Surh, Charles D.;Lee, You Jeong
    • Molecules and Cells
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    • 제42권4호
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    • pp.313-320
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    • 2019
  • Intraepithelial lymphocytes (IELs) develop through the continuous interaction with intestinal antigens such as commensal microbiome and diet. However, their respective roles and mutual interactions in the development of IELs are largely unknown. Here, we showed that dietary antigens regulate the development of the majority of $CD8{\alpha}{\beta}$ IELs in the small intestine and the absence of commensal microbiota particularly during the weaning period, delay the development of IELs. When we tested specific dietary components, such as wheat or combined corn, soybean and yeast, they were dependent on commensal bacteria for the timely development of diet-induced $CD8{\alpha}{\beta}$ IELs. In addition, supplementation of intestinal antigens later in life was inefficient for the full induction of $CD8{\alpha}{\beta}$ IELs. Overall, our findings suggest that early exposure to commensal bacteria is important for the proper development of dietary antigen-dependent immune repertoire in the gut.

BRAZING CHARACTERISTICS BETWEEN CEMENTED CARBIDES AND STEEL USED BY AG-IN BRAZING FILLER

  • Nakamura, Mitsuru;Itoh, Eiji
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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    • pp.551-554
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    • 2002
  • As a general rule, the brazing process between cemented carbides and steel used by Silver (Ag) type brazing filler. The composition of Ag type filler were used Ag-Cu-Zn-Cd type filler mainly. But, the demand of Cadmium (Cd)-free in Ag type filler was raised recently. The reason why Cd-free in Ag brazing filler were occupied to vaporize as a CdO$_2$ when brazing process, because of Cd element was almost low boiling point of all Ag type filler elements. And, CdO$_2$ was a very harmful element for the human body. This experiment was developed Cd-freeing on Ag type filler that was used Indium (In) instead of Cd element. In this experiment, there were changed from 0 to 5% In addition in Ag brazing filler and investigated to most effective percentage of Indium. As a result, the change of In addition instead of Cd, there was a very useful element and obtained same property only 3% In added specimens compared to Cd 19% added specimens. These specimens were obtained same or more deflective strength. In this case, there were obtained 70 MPa over strength and wide brazing temperature range 650-800 C. A factor of deflective strength were influenced by composition and the shape of $\beta$ phase and between $\beta$ phase and cemented carbides interface. Indium element presented as $\alpha$ phase and non-effective factor directly, but it's occupied to solid solution hardening as a phase. $\beta$ phase were composed 84-94% Cu-Ni-Zn elements mainly. Especially, the presence of Ni element in interface was a very important factor. Influence of condensed Ni element in interface layer was increased the ductility and strength of brazing layer. Therefore, these 3% In added Ag type filler were caused to obtain a high brazing strength.

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Comparison of Cholesterol-reduced Cream Cheese Manufactured Using Crosslinked β-Cyclodextrin to Regular Cream Cheese

  • Han, E.M.;Kim, S.H.;Ahn, J.;Kwak, H.S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제21권1호
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    • pp.131-137
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    • 2008
  • The objective of the present study was to compare the chemical and sensory properties of regular cream cheese (control) and cholesterol-reduced cream cheese manufactured using crosslinked ${\beta}$-cyclodextrin (${\beta}$-CD) or powdered ${\beta}$-CD. Crosslinked ${\beta}$-CD was made using adipic acid. The composition of cream cheese treated by the crosslinked ${\beta}$-CD was similar to the regular cream cheese. Approximately 91% of cholesterol-reduction was observed in the cheeses that were treated using ${\beta}$-CD, which was not significantly different between powdered vs. crosslinked ${\beta}$-CD treatments. Total amount of short-chain free fatty acids was significantly lower in both ${\beta}$-CD-treated cheeses than in the control cheese throughout the storage. The cheeses made by ${\beta}$-CD-treated cream produced much lower amounts of individual free amino acids than the control in all periods. Most rheological characteristics, except cohesiveness, decreased dramatically in the control compared with the cholesterol-reduced cream cheeses. In sensory attributes, both wateryness and spreadability in ${\beta}$-CD-treated cheeses were significantly higher than in the control during 8 wk storage. Sensory scores for sourness increased significantly in the control from 4 to 8 wk storage, however, those in the cream cheese made by crosslinked-${\beta}$-CD treated cream increased slowly during 8 wk storage, which was shown in the control during a 4 wk period. Therefore, the present study showed the possibility of cholesterol-reduced cream cheese manufacture.

포도의 섭취가 흰쥐의 노화 과정 중 지방 대사에 미치는 영향 (Effect of Grape Intakes on Lipid Metabolism of Rats during Aging)

  • 엄민영;김미경
    • Journal of Nutrition and Health
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    • 제35권7호
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    • pp.713-728
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    • 2002
  • This study was performed to see effects of whole grape, grape pomace or grape juice intakes on lipid metabolism during aging in old Sprague-Dawely male rats. One hundred twenty rats of 13 months old Sprague-Dawely were blocked into eight groups according to body weight and raised for 3, 5 or 7 months with diets containing 2% (w/w) dried powders of three different pars of grape and 0.02% (w/w) CdCl₂. Body weights of Cd groups were lower than Cd free groups. Kidney and spleen weights were incre ased with age, and EEP weights of Cd groups were lower than those of Cd free groups. Total lipid, triglyceride and total cholesterol concentration in plasma increased with age. Whole grape, grape pomace or grape juice intake lowered plasma total lipid triglyceride and total cholesterol concentrations, and especially grape pomace lowered them markedly. Whole grape, grape pomace or grape juice intake decreased liver total lipid, triglyceride and total cholesterol concentrations and increased fecal lipid excretion. Grape diets decreased and Cd administration increased TBARS concentration in LDL fraction. In conclusion, grape diets were effective in decreasing lipid levels of liver and plasma, TBARS in LDL, and in increasing HDL cholesterol. The grape pomace was most effective among three grape parts. It is plausible that grape might be recommended for the treatment or prevention of cardiovascular disease and delaying aging. (Korean J Nutrition 35 (7): 713∼728, 2002)

Variation in IR and Raman Spectra of CD3CN upon Solvation of InCl3 in CD3CN: Distinctive Blue Shifts, Coordination Number, Donor-Acceptor Interaction, and Solvated Species

  • Cho, Jun-Sung;Cho, Han-Gook
    • Bulletin of the Korean Chemical Society
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    • 제30권4호
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    • pp.803-809
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    • 2009
  • Notable blue shifts of the ν2 $C{\equiv}N$ stretching, $_{v4}$ C-C stretching and $_{v8}$ CCN deformation bands of $CD_3CN$ are observed upon solvation of $InCl_3$, resulting from the donor-acceptor interaction. The Raman spectrum in the $_{v2}$ region shows further details; at least two new bands emerge on the blue side of the $_{v2}$ band of free $CD_3CN$, whose relative intensities vary with concentration, suggesting that there exist at least two different cationic species in the solution. The strong hydrogen bonds formed between the methyl group and ${InCl_4}^-$ result in a large band appearing on the red side of the ν1 $CD_3$ symmetric stretching band. The solvation number of $InCl_3$, determined from the Raman intensities of the $C{\equiv}N$ stretching bands for free and coordinated $CD_3CN$, increases from $\sim$1.5 to $\sim$1.8 with decreasing concentration.