• Journal of the Chungcheong Mathematical Society
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• v.20 no.3
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• pp.245-259
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• 2007

We define and study a concept of $T^f$-space for a map, which is a generalized one of a T-space, in terms of the Gottlieb set for a map. We show that X is a $T_f$-space if and only if $G({\Sigma}B;A,f,X)=[{\Sigma}B,X]$ for any space B. For a principal fibration $E_k{\rightarrow}X$ induced by $k:X{\rightarrow}X^{\prime}$ from ${\epsilon}:PX^{\prime}{\rightarrow}X^{\prime}$, we obtain a sufficient condition to having a lifting $T^{\bar{f}}$-structure on $E_k$ of a $T^f$-structure on X. Also, we define and study a concept of co-$T^g$-space for a map, which is a dual one of $T^f$-space for a map. We obtain a dual result for a principal cofibration $i_r:X{\rightarrow}C_r$ induced by $r:X^{\prime}{\rightarrow}X$ from ${\iota}:X^{\prime}{\rightarrow}cX^{\prime}$.

• Bulletin of the Korean Chemical Society
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• v.20 no.7
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• pp.791-795
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• 1999

The crystal structure of a cyclopropane sorption complex of dehydrated fully Ca (2+) -exchanged zeolite X, Ca46Si100Al92O384· 30C3H6 (a = 24.988(4) Å), has been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd3 at 21(1)℃. The crystal was prepared by ion exchange in a flowing stream of 0.05M aqueous Ca(NO3)2 for four days, followed by dehydration at 460℃ and 2×10 (-6) Torr for two days, and exposure to 100 Torr of cyclopropane gas at 21(1)℃. The structure was determined in this atmosphere and refined to the final error indices R1 = 0.068 and R2 = 0.082, with 373 reflections for which I > 3σ (I). In this structure, Ca 2+ ions are located at two crystallographic sites. Sixteen Ca 2+ ions fill the octahedral sites I at the centers of the hexagonal prisms (Ca-O = 2.412(9)Å). The remaining 30 Ca 2+ ions are at sites Ⅱ; each extends 0.46Å into the supercage (an increase of 0.16Å upon C3H6 sorption) where it coordinates to three trigonally arranged framework oxygens at 2.311(8)Å. Each of the 30 cyclopropane molecules was found to complex to Ca 2+ ions at site II by the induced dipole interaction (Ca-C = 2.99(4)Å). All carbon atoms in each cyclopropane molecule are equivalent and equidistant from Ca 2+ ions at site II with which they are associated.

• Korean Journal of Crystallography
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• v.5 no.1
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• pp.14-19
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• 1994

Tlifluoromethyltriphenyl-1,2,4-tioxolane(C2IHlsF303)is triclinic, space group P1 with a=10.477(1), b= 11.056(1), c=9.917(3) A, a=104.7(1), B=122.7(1), r=63.9(1), Z=2, V=867.9(3) A3, Dc=1.43 g/cm3, λ(Mo Ka)=0.71069 A, μ=0.0116 cm-1,F(000)=384, and R=0.067 for 1713 unique observed reflections with I > 1.0 o(I). The structure was solved by direct methods and refined by fall-matrix least-squares refinement with the fixed C-H bond lengths at 0.96 A. Two phenyl rings((2) and (3)) that have the dihydral angle of 106.0°.

• Analytical Science and Technology
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• v.18 no.5
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• pp.391-395
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• 2005

The title complex, $[Cd(N_3)_2(2-ethylimidazole)_2]$, I, has been prepared and characterized by X-ray single crystallography. The complex I crystallizes in the monoclinic system, Cc space group with a = 16.200(3), b = 12.926(3), $c=7.007(1){\AA}$, ${\beta}=102.29(3)^{\circ}$, $V=1433.7(5){\AA}^3$, Z = 4, $R_1=0.0239$ and ${\omega}R_2=0.0604$ for 1874 independent reflections. Cd(II) atom has a slightly distorted octahedral coordination geometry, with four end-on (${\mu}-1$,1) bridging azido ligands and two 2-ethylimidazole ligands bonding through nitrogen atom. The central cadmium(II) atoms are run in parallel to the c-axis and are doubly bridged with neighboring cadmium(II) atoms by the end-on (${\mu}-1$,1) bridging azido ligands. Thus, this complex has a one-dimensional zigzag chain structure in which the 2-ethylimidazole is in the cis conformation.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.7 no.5
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• pp.1-12
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• 2008

In this paper, we described about core technologies required for the seamless service implementation and the communication system structure conceiving required for call & response services in order that the real-time traffic information service is consecutively provided to the vehicle moving at high speed. The SMART highway service is the information communication environment build-up concept which the real-time C&R service is comprised of the vehicle moving with 160km/h above. It was possible in case of being the low speed car in the DSRC system structure. However, there is a limit in the high speed environment as the DSRC system like a convention. In this paper, we proposed the structure of fitting for the SMART highway environment using the hand-over technique compositing the base station and several repeaters of DSRC system.

• Proceedings of the Korea Concrete Institute Conference
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• 1990.04a
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• pp.66-71
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• 1990

The prediction and estimation of R/C structure behavior subjected to earthquake type loading is partly based on the experimental results of the monotonically increased cyclic loading, rather than that of the irregularly increased cyclic loading. However, actual earthquake is typical random vibration. In this respect, comparing and analysing experimental test results of R/C specimens subjected to monotonically increased cyclic loading and irregularly increased cyclic loading, this study proposes the research direction of irregularly increased cyclic loading during earthquake.

• Korean Journal of Crystallography
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• v.12 no.1
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• pp.10-13
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• 2001

Compound PdCl₂(PhCN)₂(1) reacted with tert-butylamine(t-BuNH₂) to give trans-[PdCl₂(t-BuNH₂)₂] (2) Compound 2 was characterized by spectroscopy (¹H-NMR, /sup 13/C{¹H}-NMR, and IR) and X-ray diffraction. Crystallographic data for f2: monoclinic space group p2₁/c, a=6.298(1)Å, b=20.740(2)Å, c=10.731(1)Å, β=92.58(1)°, Z=4, R(wR₂)=0.0207(0.0543).

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2002.11a
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• pp.8-8
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• 2002

TiC core/(Ti,Mo)C rim structure in TiC-$Mo_2C$-Ni base cermet which is generally prepared by sintering below 145$0^{\circ}C$ had been believed to be generated by the solid diffusion of Mo atoms 1 into TiC grains (D. Moskowitz and M.Humenik, 1r.:1966). Afterward, it was clarified that the c core/rim structure is generated by solution/re-precipitation mechanism : (1) $Mo_2C$ grains and s small TiC grains dissolve into the Ni liquid, (2) the dissolved Mo, Ti and C atoms migrate to the s surface of TiC coarse grains, (3) the Mo, Ti and C precipitate on the surface of TiC coarse g grains and form (Ti,Mo)C solid solution rim, and (4) the Ostwald ripening (grain growth by s solution/re-precipitation mechanism) of TiC-core/(Ti,Mo)-rim grains continues, and thus the w width of (Ti,Mo)C rim (at the same time, the grain size) increases with sintering time, etc. ( (H.Suzuki, K.Hayashi and O.Terada: 1973). The TiC-core was found not to disappear even by s sintering at 190$0^{\circ}C$ (ibid.: 1974) Recently, FeSi core/$Fe_2Si_5$-rim structure in Fe-66.7at%Si thermoelectric aIloy was found to also h hardly shrink and disappear by long heating at an appropriate temperature (1999: M.Tajima and K K.hayashD. Then, the authors considered its cause, and clarified experimentaIly that the disappearance of FeSi-core/$Fe_2Ski_5$-rim structure could be attributed to the exhaustion of diffusion-contributable vacancies in core/rim structure (N.Taniguchi and K.Hayashi:2001). At p present, the authors and my coworker are investigating whether the non-disappearance of TiC c core can be explained also from the new hypothesis "Exhaustion of diffusion-contributable v vacancies in corelrim structure".ure".uot;.

• Bulletin of the Korean Chemical Society
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• v.18 no.3
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• pp.305-310
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• 1997

The synthesis and characterization of the platinum heterocyclic carboxaldehyde thiosemicarbazone complexes [NC5H4CRNNC(S)NHR'PtCl] (R=H, R'=CH3(1); R=CH3, R'=CH3(2); R=CH3, R=H(3)) and diphenylphosphinophenyl carboxaldehyde thiosemicarbazone complexes [Ph2PC6H4CHNNC(S)NHRPtCl] (R=CH3(5); R=iC3H7(6); R=Ph(7)) are described. Compounds 1-3 were prepared by reaction of Pt(SEt2)2Cl2 with 2-acetylpyridine-4-alkylthiosemicarbazone in the presence of NEt3. Compounds 5-7 were prepared using Pt(SEt2)2Cl2 in toluene with diphenylphosphinophenyl carboxaldehyde alkylthiosemicarbazone. The compounds have been characterized by microanalysis, NMR (1H, 13C, 31P) spectroscopy, and single-crystal X-ray diffraction. X-ray single crystal diffraction analysis reveals that compound 5 is a mononuclear platinum compound with P,N,S-coordination mode.

• Korean Journal of Crystallography
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• v.12 no.3
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• pp.141-144
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• 2001

From the reaction of Na[Ga(N₃)₄] with PPh₃, an ionic compound [Ph₃P(OH)]/sup +/[N₃]/sup -/ (1) was isolated. Compound 1 was characterized by spectroscopy (¹H-NMR, /sup 13C{¹H}-NMR, and IR) and X-ray diffraction. Crystallographic data for 1 : orthorhombic space group P2₁2₁2₁, a = 10.491 (4) Å, b=11.603(5)Å, c=13.149(5)Å, Z=4, R(wR₂)=0.0547(0.0978).