• Title/Summary/Keyword: $Z_2$

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Relationship between Moisture Barrier Properties and Sorption Characteristics of Edible Composite Films

  • Ryu, Sou-Youn;Rhim, Jong-Whan;Lee, Won-Jong;Yoon, Jung-Ro;Kim, Suk-Shin
    • Food Science and Biotechnology
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    • v.14 no.1
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    • pp.68-72
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    • 2005
  • Moisture sorption characteristics of edible composite films were determined and compared against moisture barrier properties. Edible composite films were Z1 (zein film with polyethylene glycol(PEG) and glycerol), Z2 (zein film with oleic acid), ZA1 (zein-coated high amylose corn starch film with PEG and glycerol), and ZA2 (zein-coated high amylose corn starch film with oleic acid). Z2 film showed the lowest equilibrium moisture content (EMC), monolayer value ($W_m$), water vapor permeability (WVP), and water solubility (WS). Surface structure of Z2 was relatively denser and finer than that of other edible films. GAB $W_m$ and C values decreased, while K values increased with increasing temperature. Correlation coefficients of WS:EMC and WVP:EMC at Aw 0.75 were higher than those of WS: $W_m$ and WVP: $W_m$, respectively. EMC values at Aw 0.75 appeared useful for evaluating or predicting moisture barrier properties of edible films.

Synthesis and Characterization of New Polyesters Having Unsaturated Groups from Bis [4-(alkyloxy)benzilidene]succinic Anhydride (Bis[4-(alkyloxy)benzilidene]succinic anhydride로부터 유도된 불포화기를 가지는 새로운 폴리에스터의 합성)

  • 김용석;진왕철;정진철
    • Polymer(Korea)
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    • v.26 no.4
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    • pp.439-444
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    • 2002
  • Several monomeric benzilidene anhydrides (2a~d) haying n-alkyloxy groups with various n-alkyl chain lengths were prepared by Stobbe condensation of diethyl succinate with 4-(n-alkyloxy)benzaldehyde (1a,b) followed by hydrolysis by the succinates and cyclodehydration of the benzilidenated succinic acids. Configurational isomerism of the monomer was investigated by spectroscopic means. It was found that monomers (2a~d) exist in (Z,Z)-isomeric structure. Polymerization was carried out in bulk at 150~$210^{\circ}C$ range in nitrogen flow. The chemical structure and thermal properties of the polymers were characterized by spectroscopic means, TGA and DSC. Their properties highly depended on their chemical structures in accordance with a side chain length.

Phospholipids from Bombycis corpus and their neurotrophic effects

  • Jung, I-Yeon;Kwon, Hak-Cheol;Nam, Sung-Hee;Chang, Seung-Jong;Cho, Sae-Yeon;Hur, In-Young;Kim, Sun-Yeon;Lee, Kang-Ro
    • Proceedings of the Korean Society of Sericultural Science Conference
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    • 2003.04a
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    • pp.46-46
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    • 2003
  • Three phospholiplds (4 6) and three aromatic amines (1 3) were obtained from the methanol extract of Bombycis corpus. Based on spectral data, their structures have been elucidated as nicotiamide(1), cytidine(2), adenine(3), 1-O-(9Z-octadecenoyl)-2-O-(8Z, llZ-octadecadienoyl)-sn-glycero-3-phosphorylcholine(4), 1,2-di-O-hexadecanoly-sn-glycero-3-phosphorylcholine(5) and 1,2-di-O-9Z-octadecenoly-sn-glycero-3-phosphorylcholine(6). (omitted)

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Substituent Effects on the Gas-Phase Pyrolyses of 2-Substituted Ethyl N,N-Dialkylcarbamates: A Theoretical Study

  • Kim, Chang-Kon;Kim, Dong-Jin;Zhang, Hui;Hsieh, Yih-huang;Lee, Bon-Su;Lee, Hai-Whang;Kim, Chan-Kyung
    • Bulletin of the Korean Chemical Society
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    • v.28 no.6
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    • pp.1031-1034
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    • 2007
  • The R- and Z-substituent effects for the gas-phase thermal decompositions of carbamates, R2NC(=O)- OCH2CH2Z, have been investigated theoretically at B3LYP level with 6-31G(d) and 6-31++G(d,p) basis sets. Both the Z- and R-substituent effects on reactivity (ΔH≠) were well consistent with experimental results, although the R-substituent effect was underestimated theoretically. No correlations were found between activation enthalpies and reaction enthalpies. The substituent effects on reactivity seemed to be complicated at a glance, but were understandable by concurrent electronic and steric factors. Variations of bond lengths at TS structures were well correlated with the Taft's σ* values and the TS structures became tighter as the Zsubstituent became a stronger electron-acceptor (δσ* > 0). However the effects of R-substituents on the TS structures were much smaller when compared to those of Z-substituents.

STAR FORMING ACTIVITY OF CLUSTER GALAXIES AT z~1

  • KIM, JAE-WOO;IM, MYUNGSHIN;LEE, SEONG-KOOK;HYUN, MINHEE
    • Publications of The Korean Astronomical Society
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    • v.30 no.2
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    • pp.503-505
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    • 2015
  • The galaxy cluster is an important object for investigating the large scale structure and evolution of galaxies. Recent wide and deep near-IR surveys provide an opportunity to search for galaxy clusters in the high redshift universe. We have identified candidate clusters of 0.8< z <1.2 from the $25deg^2$ SA22 field using an optical-near-IR dataset from merged UKIDSS DXS, IMS and CFHTLS catalogs. Using these candidates, we investigate the star forming activity of member galaxies. Consequently, at z ~1, the star forming activity of cluster galaxies is not distinguishable from those of field galaxies, which is different from members in local clusters. This means the environmental effect becomes more important for $M_{\ast}>10^{10}M_{\odot}$ galaxies at z <1.

TEICHMÜLLER SPACES OF NONORIENTABLE 3-DIMENSIONAL FLAT MANIFOLDS

  • Kang, Eun Sook;Kim, Ju Young
    • Journal of the Chungcheong Mathematical Society
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    • v.15 no.2
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    • pp.57-66
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    • 2003
  • The various deformation spaces associated with maximal geometric structures on closed oriented 3-manifolds was studied in [2], leaving out the geometry of $\mathbb{R}^3$. In this paper, we study the Weil spaces and Teichm$\ddot{u}$ller spaces of non-orientable 3-dimensional flat Riemannian manifolds. In particular, we find the Teichm$\ddot{u}$ller spaces are homeomorphic to the Euclidean spaces $\mathbb{R}^4$ or $\mathbb{R}^3$ depending on the holonomy group $\mathbb{Z}_2$ or $\mathbb{Z}_2{\times}\mathbb{Z}_2$ respectively.

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New Record of Arctoseius cetratus (Sellnick, 1940) (Mesostigmata: Ascidae) Phoretic to Sciarid Fly from Mushroom Culture in Korea

  • Keum, Eunsun;Kang, Mingu;Jung, Chuleui
    • Korean Journal of Environmental Biology
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    • v.33 no.2
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    • pp.209-214
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    • 2015
  • The Mesostigmata is an order of Subclass Acari either parasiting to diverse invertebrates or free-living predatory in terrestrial ecosystem. Phoresy is one of the unique behaviors of wingless arthropod dispersal by attaching winged arthropods. We collected mites attached on the dorsal part of abdomen adult sciarid fly, from mushroom culture. The mites were identified as Arctoseius cetratus Sellnick, 1940 in the family of Ascidae. Arctoseius cetratus has short J2, Z1, Z2, and S1, S2 setae, not reaching the bases of following setae. Posterior half of dorsal shield with longitudinal garland of puncta between J and Z setae, peritremes extending anteriorly to midlevel of coxaII. The genus Arctoseius and species Arctoseius cetratus are the first record in Korea. We provided the detail description of the species including the identification key in the family with some ecological notes.

ON FUNCTIONAL INEQUALITIES ASSOCIATED WITH JORDAN-VON NEUMANN TYPE FUNCTIONAL EQUATIONS

  • An, Jong-Su
    • Communications of the Korean Mathematical Society
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    • v.23 no.3
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    • pp.371-376
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    • 2008
  • In this paper, it is shown that if f satisfies the following functional inequality (0.1) $${\parallel}\sum\limits_{i,j=1}^3\;f{(xi,yj)}{\parallel}{\leq}{\parallel}f(x_1+x_2+x_3,\;y_1+y_2+y_3){\parallel}$$ then f is a bi-additive mapping. We moreover prove that if f satisfies the following functional inequality (0.2) $${\parallel}2\sum\limits_{j=1}^3\;f{(x_j,\;z)}+2\sum\limits_{j=1}^3\;f{(x_j,\;w)-f(\sum\limits_{j=1}^3\;xj,\;z-w)}{\parallel}{\leq}f(\sum\limits_{j=1}^3\;xj,\;z+w){\parallel}$$ then f is an additive-quadratic mapping.

THE MEAN-SQUARE ERROR BOUNDS FOR THE GAUSSIAN QUADRATURE OF ANALYTIC FUNCTIONS

  • Ko, Kwan-Pyo;Park, U-Jin
    • Journal of the Korean Mathematical Society
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    • v.34 no.2
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    • pp.293-307
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    • 1997
  • In this paper we present the $L^2$-estimation for the kernel $K_n$ of the remaider term for the Gaussian quadrature with respect to one of four Chebyshev weight functions and the error bound of the type on the contour $$ $\mid$R_n(f)$\mid$ \leq \frac{2\pi}{\sqrt{l(\Gamma)}} max_{z\in\Gamma}$\mid$f(z)$\mid$ (\smallint_\Gamma $\mid$K_n(z)$\mid$^2$\mid$dz$\mid$)^\frac{2}{1}, $$ where $l(\Gamma)$ denotes the length of the contour $\Gamma$.

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Identifying Cluster Candidates in CFHTLS W2 Field

  • Paek, Insu;Im, Myungshin;Kim, Jae-Woo
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.1
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    • pp.59.2-59.2
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    • 2018
  • Recent studies of galaxy clusters have shown that the galaxy clusters in dense environment tend to have lower star formation rate in local universe with z < 1. However, this correlation is not significant in galaxy clusters with z > 1. The study of galaxy clusters around z=1 can yield insight into cosmological galaxy evolution. Nevertheless, the identification of galaxy clusters beyond the scope of immediate local universe requires wide field data in optical and near-infrared bands. By incorporating data from Canada-France-Hawaii Telescope Legacy Survey(CFHTLS) and Infrared Medium-Deep Survey(IMS), the photometric redshifts of galaxies in CFHTLS W2 field were calculated. Using spatial distribution and photometric redshifts, the galaxies in the field were divided into redshift bins. The image of each redshift bin was analyzed by measuring the number density within proper distance of 1Mpc. By comparing high density regions in consecutive redshift bins, we identified the cluster candidates and mapped the large-scale structure within the CFHTLS W2 field.

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