• 제목/요약/키워드: brown pigment formation

검색결과 34건 처리시간 0.059초

Spinel Pigment의 생성반응에 관한 연구 (A Study on the Formation of Spinel Pigment(Green Pigment based on Magnesium-Chrome))

  • 이응상;박철원;황성연
    • 한국세라믹학회지
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    • 제12권1호
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    • pp.29-36
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    • 1975
  • This study was conducted to research the formation, color development and application for colored glazes of the spinel solid solutions of the green pigment. On specimens prepared by calcining the oxide and basic carbonate mixture at 1250℃ for 1.5 hour, the x-ray analysis, measurement of reflectance and the test of their stabiality as a glaze pigment were carried out. The results are summarized as follows 1) Each sample is composed of single spinel and not of mixture of spinel. 2) Formation of continuous soild solution, except for a few instances, pertaining to Vegard's law was confirmed by means of the x-ray analysis. 3) The more difference between absorption and reflectance lies, the lighter colors are. When the absorption occurs at the high-reflectance, the excitation purity becomes low. On the contrary when the absorption takes place at the low-reflectance, the excitation purity becomes low. On the contrary when the absorption takes place at the low-reflectance, the excitation purity is higher. 4) Colors obtained in the CdO-MgO-Cr2O3-Al2O3 system, as the amounts of Al3+ increased, change from green through brown to pink, and the absorption peak shifts towards violet region. 5) An increase in Co2+ in the CoO-MgO-Cr2O3-Al2O3 system, changes the color from blue green to dark blue. The excitation purity is higher, and the absorption peak shifts toward regions. 6) Colors are green in the NiO-MgO-Cr2O3 and CdO-MgO-Cr2O3 systems in general, but in the ZnO-MgO-Cr2O3 system brillant hue is not obtained. 70 According to the results of the colored glaze test, the spinels turn outto be stable as brilliant glaze pigment in the calcium-magnesia glaze.

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Color Formation Mechanism of Ceramic Pigments Synthesized in the TiO2-SnO-ZnO Compounds

  • Kim, Soomin;Kim, Ungsoo;Cho, Woo-Seok
    • 한국세라믹학회지
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    • 제55권4호
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    • pp.368-375
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    • 2018
  • This study deals with the color formation of ceramic pigment in the $TiO_2$-SnO-ZnO system. We designed compounds to control the color formation depending on the composition using the Design of Experiment. The color coordinate values of synthesized pigments, $L^*a^*b^*$ were measured and statistically analyzed color for changing elements depending on its composition. The relationship between the major crystalline phases and chromaticity was examined using XRD, and the oxidation states of each element were analyzed by XPS. The synthesized pigments based on the compound design exhibited various color changes ranging from yellow-orange to green-blue and brown. The statistical analysis on the spectrophotometer results shows that $a^*$ and $b^*$ values decreased with $TiO_2$ content, and increased with SnO content. Yellow-orange color was detected with the main peak of SnO, and the green-blue color developed with the main peak of $Zn_2TiO_4$. The $a^*$ and $b^*$ values increased with increased SnO peak intensity, and decreased with increased $Zn_2TiO_4$ peak intensity. The results revealed that pigment color formation was influenced by changes in the main crystalline phases and crystalline intensity. However, XPS analysis of the oxidation states of each element showed little correlation with the pigment chromaticity result.

패류 건제품의 저장 중 지방산 조성의 변화 (Changes in Fatty Acid Composition of Dried Shellfish during Storage)

  • 조호성;이강호;손병일;조영제;이종호;임상선
    • 한국수산과학회지
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    • 제32권4호
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    • pp.416-419
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    • 1999
  • 홍합이나 바지락과 같은 패류 건제품의 효율적인 이용방안의 일환으로 저장온도($4\pm2^{\circ}C$$25\pm2^{\circ}C$)에 따른 산화패턴 특히 갈변도와 지방산 조성의 변화를 연구하였다. 갈변도의 경우, 지용성 갈변도는 저장온도가 높을수록 또한 같은 온도에서 저장했을 때에도 바지락이 홍합보다 다소 높았으나, 수용성 갈변도는 두 종 모두 저장온도에 관계없이 거의 변화가 없었다. 홍합과 바지락 생시료의 지방산 조성 중 polyene산이 각각 $46.29\%$$44.79\%$로 포화산이나 monoene산에 비해 상대적으로 높은 비율을 나타내었다. 두 종 모두 포화산 중에서는 16:0, monoene산의 경우에는 16:1 그리고 polyene산에서는 20:5가 가장 높았다. 특히 저장중 16:0의 증가와 20:5 및 22:6의 감소가 컸으며, 또한 $25^{\circ}C$ 저장구가 $4^{\circ}C$ 저장구보다 변화 폭이 더 컸다. 중성지질과 인지질의 지방산조성은 홍합의 경우 polyene산의 비율은 중성지질 ($36.90\%$)보다 인지질 ($51.70\%$)에서 더 높았으나, 포화산과 monoene산은 중성지질에서 높았다. 바지락의 경우도 홍합과 비슷한 경향이었으나, 포화산에 대한 polyene산의 비율 (P/S)은 중성지질의 경우 홍합($0.92\%$)과 바지락($0.94\%$) 양자간에 큰 차이가 없었으나, 인지질에서는 홍합($1.42\%$)보다 바지락($1.81\%$)에서 다소 높았다.

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Ethidium Bromide에 의한 Streptomyces bobili(YS-40)의 R-Plasmid 제거 (Elimination of R-Plasmid in Streptomyces bobili (YS-40) by Ethldium Bromide)

  • 김상달;도재호
    • 한국미생물·생명공학회지
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    • 제10권4호
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    • pp.289-295
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    • 1982
  • Streptomyces bobili (YS-40) 의 Hg, Ag, penicillin-G, ampicillin, chloramphenicol, oxytetracycline, streptomycin, kanamycin에 대한 생육최소저해농도는 각각 15, 10, >3,000, >100, >1,000. >100. <5, <5 $\mu\textrm{g}$/$m\ell$였으며 본 균주의 R-plasmid를 제거시키기 위하여 ethidium bromide, acriflavine, sodium dodecyl sulfate 등의 curing agent를 처리시킨 결과를 요약하면 다음과 같다. Ethidium bromide를 10$\mu\textrm{g}$/$m\ell$의 농도로 처리했을 때 98.0% 정도의 R-plasmid를 제거시킬 수 있었다. pH 7.0에서 curing시킴으로서 R-plasmid가 가장 잘 제거되었으며 분균을 24시간동안 배양해서 curing시킴으로서 R-plasmid의 제거율이 가장 높게 나타났다. Ethidium bromide에 의해서 R-plasmid가 제거된 균과 원균을 여러가지 색소생성배지에서 배양시켜 배양상의 특성을 조사해 본 결과 peptone-beef extract agar 배지에서 aerial mass color가 greyish pink에서 grey로 변했으며 tryptone-yeast extract broth에서 배지에서 soluble pigment가 pale brown에서 무색으로 변했다. 이 결과로는 aerial mycelium, melanin 생성과 R-plasmid 는 무관하다고 추측된다.

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Changes in Physicochemical Properties of Soybean Protein due to Acetylation during Incubation with Glucose

  • Kim, Myung-Hee;Kim, Jin-Hee;Kim, Kang-Sung
    • 한국환경보건학회지
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    • 제30권4호
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    • pp.308-313
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    • 2004
  • Native and acetylated soybean protein with acetylation percentage of $25\%$ were incubated with glucose to induce Maillard reaction. Acetylation of ${\varepsilon}$-amino group of lysine residues changed the conformation of soybean protein. The direct uv spectrum of native and acetylated soybean protein showed conformational changes with accessibility of tyrosine and tryptophan residues increased. Acetylation suppressed Maillard reaction between soybean protein and glucose. Acetylated soybean protein showed improved water sorption, fat binding, foam formation, and emulsion activity of the protein, but depressed brown pigment development and trypsin digestion. Thus aceylation prevented deterioration of certain functional characteristics that occurred during storage, besides causing functional characteristics to be improved on its own.

유산동에 대한 Saccharomyce cerevisiae의 저항성에 관한 연구 (A study on the resistance of saccharomyces cerevisiae to copper sulfate)

  • 이민재;이진기
    • 약학회지
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    • 제3권1호
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    • pp.15-20
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    • 1957
  • Resume 1. The toxic effect of $CuSO_4$ on the growth of yeast began in the 0.2mM and colony formation was completely inhibited in the 3mM $CuSO_4$ media. 2. The yeast strain which was trained sucessively from lower concentration media to higher one, could grow even in 10mM $CuSO_4$ media. 3. Rlb strain produced brown pigment in copper media. 4. Resistance of Rlb strain to $CuSO_4$ did not revert in non copper media. 5. The appearance of resistant strain was regarded as the result of "Mutation and Selection". 6. The alcohol fermentation ability of Rlb strain was lower than that of parent strain. 7. Rlb strain yielded some effective substance which induced the parent strain to resist against $CuSO_4$. 8. The dehydrogenase activity of yeast was inhibited by $CuSO_4$.

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Nutritional Regulation of Morphological and Physiological Differentiation on Surface Culture of Streptomyces exfoliatus SMF13

  • KYE JOON LEE;KIM, IN SEOP
    • Journal of Microbiology and Biotechnology
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    • 제5권4호
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    • pp.200-205
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    • 1995
  • Nutritional factors regulating the morphological differentiation and physiological differentiation of Streptomyces exfoliatus SMF13 on surface cultures were evaluated. S. exfoliatus SMF13 produced leupeptin and chymotrypsin-like protease (CTP) at the stage of substrate mycelium growth, and leupeptin-inactivating enzyme (LIE) and trypsin-like protease (TLP) at the stage of aerial mycelium growth. The activity of leupeptin and CTP was high in the region of active growing substrate mycelium, whereas the activity of LIE and TLP was high in the region of aerial mycelium or spores. The differentiations were induced in glucose-limited conditions or by the addition of glucose anti-metabolite (methyl $\alpha$-glucopyranoside), but repressed by high concentrations of glucose or casamino acids. Morphological differentiation (formation of aerial mycelia and spores) was closely related with physiological differentiation (formation of brown-pigment, LIE and TLP). The local distribution of leupeptin, CTP, LIE, and TLP in a developing colony showed that colony development correlated with the production and functions of the compounds: CTP is essential for providing a nitrogen source for mycelium growth: leupeptin regulates TLP activity: LIE inactivates leupeptin: TLP hydrolyzes nongrowing mycelium.

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MgO-$SnO_2$계 Spinel 채요에 대한 NiO, $TiO_2$의 영향 (Influence of NiO, $TiO_2$ for MgO-$SnO_2$ System Spinel Pigment)

  • 이응상;박철원;황성윤
    • 한국세라믹학회지
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    • 제13권2호
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    • pp.24-30
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    • 1976
  • To observe the influence of tetrahedral and octahedral preference of cations of Ni2+, Ti4+ upon the formation and the color development of the MgO-SnO2 spinel containing Ni2+ and Ti4+ ions, the gradual substitution of Ni2+ ions for Mg2+ ions and of Ti4+ ions for Sn4+ ions of the spinel in NiO-MgO-SnO2-TiO2 system was carried out. On samples prepared by calcining the oxide and basic carbonate mixtures at 130$0^{\circ}C$ for 1.5 hour, the X-ray analysis, measurement of reflectance and the test of their stability as a glaze pigment were also carried out. On samples prepared by calcining the oxide and basic carbonate mixtures at 130$0^{\circ}C$ for 1.5 hour, the X-ray analysis, measurement of reflectance and the test of their stabiality as a glaze pigment were also carried out. The results are summarized as follows. 1) As increasing the amounts of Ni2+ ions in the xNiO.(2-x)MgO.SnO2 system, spinel was not formed easily, and the mixed-spinel was formed in NiO.MgO.SnO2 of x=1 but the spinels was not formed completely in the range of x>1.5 2) The spinels was not more formed in NiO-MgO-TiO2 system than NiO-MgO-SnO2 system. Therefore, Ti4+ ions have strong octahedral preference than Sn4+ ions. The color changed the yellow region little. The mixed-spinel or non-spinel was formed easily NiO.TiO2, MgO.TiO2 of illmenite type as the gradual substitution of Ti4+ ions for Sn4+ ions. 3) The results of glaze test. The color changed from white through graish brown to brown as the gradual substitution of Ni2+ ions for Mg2+ ions in calcium-zinc glaze and calcium glaze, and from white through light yellowish beige to dull beige in tile glaze. Also, the color did not change generally as the gradual substitution of Ti4+ ions for Sn4+ ions in NiO-MgO-SnO2-TiO2 system.

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우렁쉥이 저온저장 및 품질안정성에 관한 연구 (Cold Storage and Quality Stability of Ascidian, Halocynthia roretzi)

  • 이강호;이민주;정병천;홍병일;조호성;이동호;정우진
    • 한국식품과학회지
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    • 제26권4호
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    • pp.382-388
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    • 1994
  • 최근 대량 생산되고 있는 우렁쉥이의 비수확기 가공원료 확보를 위한 일환으로 우렁쉥이를 10% 소금용액에 10초간 열탕 처리한 것과 0.2% $NaHSO_3$용액에 1분 침지한 것을 각각 빙장, $-17^{\circ}C$ 그리고 $-35^{\circ}C$에서 저장하면서 그 적성과 저장중의 품질변화 등을 검토하였는데 그 결과를 요약하면 다음과 같다. 1. 휘발성 염기질소는 빙장 저장시 급격히 분해되어 저장 35일 이후에는 $30{\sim}40mg/100g$의 값을 나타내었고, glycogen의 함량은 저장기간이 길어짐에 따라 점점 감소하여 빙온저장의 경우에는 급격히 분해되어 85일 경과후에는 검출되지 않았다. 2. 갈변도는 전반적으로 지용성 갈변도값이 수용성 갈변도에 비해 높은 값을 나타내었으며 수용성 갈변도의 경우는 시료에 따른 큰 차이가 없으나, 지용성 갈변도는 10% 소금 용액에서 가열처리한 것이 0.2% $NaHSO_3$용액 처리보다 높게 나타났다. 3. 핵산관련물질은 AMP의 함량이 다소 높았으며, 저장중의 inosine과 hypoxanthine이 상당량 축적되었다가 감소하는 경향이었으나 시료간의 큰 차이는 나타나지 않았다. 관능평가는 빙장한 경우 저장 25일 경까지 우수하였고, $-17^{\circ}C$$-35^{\circ}C$에서 0.2% $NaHSO_{3}$ 용액에 처리한 시료들은 저장 85일 이후에도 양호하였다. 이상의 결과에 의하여 저장 25일 경까지는 빙장의 경우가 가장 양호 하였고 , 0.2% $NaHSO_{3}$ 용액에 처리한 시료들은 저장 85일 이후에도 양호하였다. 이상의 결과에 의하여 저장 25일 경까지는 빙장의 경우가 가장 양호 하였고 , 0.2% $NaHSO_{3}$ 용액에 침지하여 $-35^{\circ}C$에서 저장한 시료가 저장 85일경과 후에도 품질면에서 가장 우수하였다.

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Effect of Starvation on Kidney Melano-macrophage Centre in Sub-adult Rock Bream, Oplegnathus fasciatus (Temminck and Schlegel)

  • Seol, Dong-Won;Hur, Jun-Wook;Kim, Dong-Soo;Nam, Yoon-Kwon;Bang, In-Chul;Park, In-Seok
    • Fisheries and Aquatic Sciences
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    • 제12권1호
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    • pp.49-53
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    • 2009
  • We conducted a histological analysis to investigate the influence of nutritional changes on melano-macrophages (MMs) accumulation in the kidney of sub-adult rock bream (Oplegnathus fasciatus). Four experimental groups were established (initial control, control, fed and starved), and fed commercial feed amounting to 1-3% of their body weight for 2 weeks prior to initiation of experiments. Kidney MMs with dark brown pigment were randomly observed in the kidneys of starved fish, increasing rapidly after 4 weeks, while deposition levels remained low throughout the experiment in the control and fed groups. These results suggest that catabolic tissue breakdown is a major factor contributing to the formation of pigments within MMs. Results also suggest that the degree of MMs deposition in the kidney can be used as alternative indicators in identifying starvation in wild and cultured rock bream.