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The Morphological Properties of Acorn Starch Granules and Starch Gels (도토리 전분 및 전분겔의 형태학적 특성 연구)

  • 김영아
    • Korean journal of food and cookery science
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    • v.8 no.1
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    • pp.9-14
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    • 1992
  • The morphological properties of acorn starch granules and starch gels were examined with scanning electron microscope and X-ray diffractometer. The shape of acorn starch granule was rounded triangular and some elliptical. The size distribution of starch granule was also analyzed. The mean value of minor axis, major axis and the ratio of those were 4.785 $\mu\textrm{m}$, 7.30 $\mu\textrm{m}$ and 0.68, respectively. The surface micro-structure of acorn starch gels were investigated by SEM. Acorn crude and refined starch gel were very different in surface micro-structure. X-ray diffraction pattern of acorn starch was C-type, and the pattern of acorn starch gels were extremely different because of disintegration of starch granules by gelatinization. The diffraction intensity of acorn refined starch gel was slightly higher than crude starch gel.

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Structure of Tetra-ter-butyl-tetrapropionyloxycalix[4]arene (Tetra-tert-butyl-tstrapropionyloxycalix [4] arene의 구조)

  • 김회진;노광현
    • Korean Journal of Crystallography
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    • v.4 no.1
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    • pp.25-35
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    • 1993
  • Tetra-tert-butyl-tetrapropionycalix (4) arena (C56H7208) is Triclinic, space group Pl, with a=13.664(5), b=17.585(5), c=12.863(2)A, a=109.33(2), B=111.97(2), γ=76.45(3) ˚, Z=2, V=2684.08A3, D, =1.152g/cm3, Dm=1.15g/cm3. The intensity data were collected on an Enraf-Nonius CAD-4 Diffractometer with a graphite monochromated Mo-Ka radiation. The structure was solved by direct methods and refined by leastsquares methods. The final R factor was 0.084 for 2561 observed reflections. The configuration of the molecule from the X-ray crystallographic investigation has the partial cone conformation, three tort-butylphenyls are down and a tort-butylphenyl is up. Three propionyloxy groups direct toward the exterior of the macrocycle cavity.

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Structure of Hydroxy-bisbenzoyloxy-allyloxycalix[4]arene (Hydroxy-bisbenzoyloxy-allyloxycalix[4]arene의 구조)

  • Lee, Bo-Hyeong;Jo, Seon-Hui;Park, Yeong-Ja
    • Korean Journal of Crystallography
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    • v.8 no.2
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    • pp.111-118
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    • 1997
  • The structrue of hydroxy-bisbenzoyloxy-allyloxycalix[4]arene (C45H36O6) has been determined by X-ray crystallography. The crystals are monoclinic, space group P21, unit cell constants a=11.045(3), b=33.545(2) c=10.319(4)Å, β=113.86(2)˚, Z=4, V=3496.0(1.8) Å3, DC=1.28 gcm-3. The intensity data were collected on an Enraf-Noninus CAD-4 Diffractometer with a graphite monochromated Mo-Kα radiation. The structure was solved by direct method and refined by full-matrix least-squares calculations to a final R value of 0.076 for 2945 observed reflections. Two independent enantiomeric molecules are crystallized in a 1:1 racemate mixture. They have the flattened cone conformation with the flattening hydroxy1 pheny1 rings. There is an intramolecular hydrogen bond in both molecules.

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Structure of Tetrapropionyloxycalix[4]arene (Tetrapropionyloxycalix[4]arene의 구조에 관한 연구)

  • 박영자;김현희
    • Korean Journal of Crystallography
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    • v.6 no.2
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    • pp.80-87
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    • 1995
  • The structure of Tetrapropionyloxycalix[4]arene(C40H40O8) has been studied by X-ray diffraction method. The crystal is monoclinic a=13.921(3), b=13.552(2), c=19.840(5)Å, β=110.38(2)°, Z=4 T=297K, Dc=1.23gcm-3, F(000)=1376, Systematic absences : hkl none, h0l : h+l=2n, 0k0: k=2n define space group P21/n. The structure was solved by direct method and refined by full-matrix least-squares methods to final R of 0.06 for 2514 observed reflections. The macrocycle exists in partial cone conformation. Three propionyl groups direct toward the exterior of the macrocycle cavity.

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