• Electrical & Electronic Materials
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• v.12 no.4
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• pp.1-9
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• 1999

• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.397-401
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• 2009

The complexes of $C_2-\;and\;C_6$-dihydroceramides with transition metal ions have been investigated by using Electrospray ionization-tandem mass spectrometry (ESI-MS/MS). The formation and fragmentation pathways of several doubly charged cluster ions as well as singly charged cluster ions of $C_2-\;and\;C_6$-dihydroceramides with transition metal ions have studied by ESI-MS/MS in the positive mode. Under ESI conditions, dihydroceramides form singly and doubly charged complexes with transition metal ions $(Mn^{2+},\;Fe^{2+},\;Co^{2+},\;Ni^{2+},\;and\;Zn^{2+}\;except\;Cu^{2+})$ with the compositions of $[DHCer+M+2H^2O-H]^+,\;[2DHCer+M+2H2O-H]^+,\;[3DHCer+M+2H2O-H]^+,\;[2DHCer+M]^{2+},\;[3DHCer+M]^{2+},\;[4DHCer+M]^{2+},\;[5DHCer+M]^{2+},\;and\;[6DHCer+M]^{2+}\;(DHCer\;=\;C_2-\;or\;C_6$-dihydroceramide, M = transition metal ion). The different complexation behavior of copper is responsible for relatively lower affinity of dihydroceramides to copper compared to those of other transition metals. It is also found that in the mass spectrum of the dihydroceramide complexes with copper(II), [2DHCer+Cu-H]$^+$ was observed with considerable intensity as well as [2DHCer+Cu+2$H_2O-H]^+$ due to its different geometry from those of other metals.

• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.445-448
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• 2009

This study examined the effect of the uptake of one and two electrons on the atomic structure of three isomers of $C_{20}$ clusters, namely the ring, bowl (corannulene like), and cage (the smallest fullerene). Geometry optimizations were performed using the hybrid density functional (B3LYP) methods for neutral, singly and doubly charged $C_{20},\;{C_{20}}^-,and\;{C_{20}}^{2-}$. These results show that the symmetry of the lowest energies for ring and bowl isomers were not changed, whereas the increasing order of energy for the cage (the smallest fullerene) isomers was changed from $D_{2h}\;<\;C_{2h}\;{\leq}\;C_2\;of\;C_{20}\;through\;Ci\;<\;C_{2h}\;<\;C_2\;<\;D_{2h}\;of\;{C_{20}}^-\;to\;Ci\;<\;C_2\;<\;D_{2h}\;<\;C_{2h}\;of\;{C_{20}}^{2-}$. The reduced symmetry isomers of the cage have comparative energy and the ground state symmetry of the neutral and single and double charged $C_{20}$ decreased with increasing number of electrons taken up in the point of energetics. Interestingly, the difference in energy between the ground state and the next higher energy state of ${C_{20}}^{2-}$ was 3.5kcal/mol, which is the largest energy gap of the neutral, single anion and double anion of the cage isomers examined.

• The Korean Journal of Ceramics
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• v.5 no.2
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• pp.131-136
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• 1999

Yttria stabilized zirconia(YSZ) films were deposited on porous NiO substrates and quartz plates by the thermal CVD using $ZrCl_4, YCl_3$ as precursors, and $O_2$ as a reactive gas at atmospheric pressure. The evaporation temperature of $ZrCl_4$ was varied from $250^{\circ}C$ to $550^{\circ}C$ while the temperatures of $YCl_3$ and the substrate were varied from $1000^{\circ}C$ to $1030^{\circ}C$. As the evaporation temperature of $ZrCl_4$ increased, the deposition rate of $ZrO_2$ decreased, contrary to our expectation. As a result of the decreased deposition rate of $ZrO_2$, the yttria content increase. The high evaporation temperature of $ZrCl_4$ makes the well-faceted crystal while the low evaporation temperature leads to the cauliflower-shaped structure. The dependence of the evaporation temperature on the growth rate and the morphological evolution was interpreted by the charged cluster model.

• Bulletin of the Korean Chemical Society
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• v.22 no.11
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• pp.1224-1230
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• 2001

Single crystals of nanocomposite [GaO4Al12(OH)24(H2O)12][Al(OH)6Mo6O18]2(OH)${\cdot}$30H2O, 2, were obtained by the reaction between [GaO4Al12(OH)24(H2O)12]7+ and [Mo7O24]6- clusters in an aqueous solution, analogously to the [AlO4Al12(OH)24(H2O)12][Al(OH)6Mo6O18]2(OH)${\cdot}$29.5H2O nanocomposite, 1. The crystal structure of 2 was determined by single crystal x-ray diffraction; space group $C2}c$ (No. 15), a = 27.418(2) $\AA$, b = 15.647(2) $\AA$, c = 23.960(4) $\AA$, $\beta$ = $102.850(9)^{\circ}$, V = 10,021.5(20) $\AA3$ , Z = 4. Detailed analysis of the structural data show that the clusters are held by intimate hydrogen bondings of the surface O2- and OH- groups of the clusters as well as the ionic interactions between the oppositely charged cluster ions.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.2
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• pp.135-142
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• 2012

In the present study, a parallel processing method running on a multi-core PC-Cluster is introduced to produce digital surface model (DSM) and digital terrain model (DTM) from huge airborne laser scanning data. A hybrid model using both message passing interface (MPI) and OpenMP was devised by revising a conventional MPI model which utilizes only MPI, and tested on a multi-core PC-Cluster for performance validation. In the results, the hybrid model has not shown better performances in the interpolation process to produce DSM, but the overall performance has turned out to be better by the help of reduced MPI calls. Additionally, scheduling function of OpenMP has revealed its ability to enhance the performance by controlling inequal overloads charged on cores induced by irregular distribution of airborne laser scanning data.

• The Korean Journal of Ceramics
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• v.4 no.2
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• pp.156-161
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• 1998

We have measured changes of the non-stoichiometry, $\Delta\delta$, in Fe-doped nicked oxide , by thermogravimetry for four iron fractions, x=0.01, 0.031, 0.057 and 0.10, and three temperatures, T=1273, 1373 and 1473 K. The obtained data can be modelled by a defect structure in which substitutional trivalent iron ions, FeNi, are compensated by cation vacancies, $V_{Ni}$", and (4:1)-clusters. These clusters consist of tetravalent interstitial iron, $Fe_i\;^4$

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.957-960
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• 2008

The influences of silicon and MgO seed particle on the reconstruction characteristics of MgO protective layer were investigated to clarify the mechanism of reconstruction and exaggerated grain growth (EGG) in AC-PDP. The reconstruction and EGG are closely correlated with the driving force for nucleation and growth, interface energy and initial size distribution of MgO protective layer in plasma space during discharge in AC-PDP.

• Bulletin of the Korean Chemical Society
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• v.14 no.1
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• pp.55-58
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• 1993

In order to determine the cobalt substituting site in $AlPO_4-5$ framework, ASED-MO theory has been used. The substitution of cobalt for aluminum is energetically more favorable than that for phasphorous. The stabilized energy of the former is 51 eV lower than that of the latter. The calculated net charge was +1.27 for Al, +0.85 for P, and +1.56 for Co, respectively. The valence electron population (VEP), reduced overlap population (ROP) and net charge for the charged cluster models were compared for $AlPO_4-5$ and $CoAlPO_4-5$ systems. Then, twe find that the covalency of P-O bond was greater than that of Al-O bond.

• The Journal of the Korea Contents Association
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• v.21 no.10
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• pp.702-711
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• 2021

In order to examine the type of PAI profile for criminally charged juvenile offenders, the study sought to find out personality types and behavioral characteristics of 251 juvenile offenders and 173 ordinary adolescents from 2018-2020. Looking at the overall profiles of juvenile offenders and ordinary adolescents, we found differences in Infrequency(INF), Mania(MAN), Antisocial Features(ANT), Alcohol problems(ALC), Drug problems(DRG), Aggression (AGG), and Dominance(DOM) and Warmth(WRM). Based on these results, we perform clustering as factors Antisocial features(ANT), Aggression(AGG), and Dominance (DOM) with an average difference of more than five points. It was classified as Cluster 1 with a high percentage of adolescents and Cluster 2 with a high percentage of juvenile offenders, and Cluster 1 was named as a defense group because it showed a similar model to the profile of ordinary adolescents. The profile type of cluster 2 was named externalization, which can be represented as an externalization group. The results were similar to previous studies, and the profile type of juvenile offenders has higher overall clinical scale than that of ordinary adolescents, indicating behavioral problems. Continued research on juvenile offenders could lead to understanding of youth as well as juvenile offenders.