• Korean Journal of Materials Research
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• v.4 no.7
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• pp.792-797
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• 1994

Force fields of syndiotactic isoregic PVF crystal have been extracted by optimizing a structure of 2,4,6-trifluoroheptane with ab initio Quantum mechanical method with 6-31G * * basis set, and applied to calculate the structure parameters and elastic constants of the material. The cell parameters turned out to be 5.205$\AA$, of a axis(chain axis), 8.457$\AA$, of b axis and 4.621$\AA$ of c axis. These parameters are in fair agreement with those of the atactic X-ray structure(5.04$\AA$, 8.57$\AA$, and 4.95$\AA$,respectively). The young's modulus of defect free syndiotactic PVF crystal was computed to be 267 GPa comparable to those of polyvinilidene fluoride(277-293 GPa) and polyethylene(264-337 GPa) crystals. Bulk modulus value obtained at optimum geometry is more than twice greater than that obtained at experimental geometry due to large difference of elastic compliance constant (especially Sgj element) at these two different geometries.

• Bulletin of the Korean Chemical Society
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• v.14 no.6
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• pp.678-681
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• 1993

The new ternary phase $UP_2S_6$ has been prepared and structurally characterized. The compound is isostructural with $ZrP_2S_6$ and $ThP_2S_6$ but is different from $TiP_2S_6$. The structure has been determined by a single crystal X-ray diffraction technique. $UP_2S_6$ crystallizes in the the tetragonal system $({C^2}_{4h}-P4_2/m,\;a=6.797(7)\;{\AA},\;c=9.738(12)\;{\AA})$ with two formula units in the unit cell. The structure can be described in terms of $U^{4+}$ and ${P_2S_6}^{4-}$ ions. This hexathiohypodiphosphate anion $({P_2S_6}^{4-})$ has ideally staggered conformation. The $U^{4+}$ cation is coordinated by 8 sulfur atoms in a slightly distorted dodecahedral geometry (42m). The distribution of sulfur atoms is very well optimized for this geometry.

• Advances in Traditional Medicine
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• v.10 no.4
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• pp.319-321
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• 2010

Plant saponins are widely distributed amongst plants and have a wide range of biological properties. Icosahydropicenic acid, $C_{51}H_{80}O_{19}$ ((4S,6bS)-8a-((4,5-dihydroxy-6-methyl-3-((3R)-3,4,5-trihydroxy-6-methyl-tetrahydro-2H-pyran-2-yloxy)-tetrahydro-2H-pyran-2-yloxy)carbonyl)-2-hydroxy-4, 6a, 6b, 11, 14b-pentamethyl-11-(2-methylprop-1-enyl)-3-(3,4,5-trihydroxy-6-(hydroxymethyl) - tetrahydro-2Hpyran-2-yloxy)-1, 2, 3, 4, 4a, 5, 6, 6a, 6b, 7, 8, 8a, 9, 10, 11, 12, 12a, 14, 14a, 14b-icosahydropicene-4-carboxylic acid), a new saponin was first time isolated from the roots of Clerodendrum Serratum (L) Moon (Verbenaceae). The structure elucidation of the compound was carried out by $^1H$ NMR and DART-MS studies.

• Earthquakes and Structures
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• v.6 no.4
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• pp.351-373
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• 2014

This paper investigates the seismic response of lightweight acceleration-sensitive non-structural components (NSCs) mounted on irregular reinforced concrete (RC) primary structures (P-structures) using non-linear dynamic finite element (FE) analysis. The aim of this paper is to study the influence of NSC to P-structure vibration period ratio, peak ground acceleration, NSC to P-structure height ratio, and P-structure torsional behaviour on the seismic response of the NSCs. Representative constitutive models were used to simulate the behaviour of the RC P-structures. The NSCs were modelled as vertical cantilevers fixed at their bases with masses on the free ends and varying lengths so as to match the frequencies of the P-structures. Full dynamic interaction is considered between the NSCs and P-structures. A set of 21 natural and artificial earthquake records were used to evaluate the seismic response of the NSCs. The numerical results indicate that the behaviour of the NSCs is significantly influenced by the investigated parameters. Comparison between the FE results and Eurocode (EC8) predictions suggests that EC8 underestimates the response of NSCs mounted on the flexible sides of irregular RC P-structures when the fundamental periods and heights of the NSCs match those of the P-structures. The perceived cause of this discrepancy is that EC8 does not take into account the amplification in the dynamic response of NSCs induced by the torsional behaviour of RC P-structures.

• Journal of the Korean Ceramic Society
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• v.53 no.6
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• pp.628-634
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• 2016

The 8 wt% yttria($Y_2O_3$) stabilized zirconia ($ZrO_2$), 8YSZ, a typical thermal barrier coating (TBC) for turbine systems, was fabricated under different starting powder conditions and coating parameters by atmospheric plasma spray (APS) coating process. Four different starting powders were prepared by conventional spray dry method with different additive and process parameter conditions. As a result, large- and small-size spherical-type particles and Donut-type particles were obtained. Dense structure of 8YSZ coating was produced when small size spherical-type or Donut-type particles were used. On the other hand, 8YSZ coating with a porous structure was formed from large-size spherical-type particles. Furthermore, a segmented coating structure with vertical cracks was observed after post heat treatment on the surface of dense structured coating by argon plasma flame at an appropriate gun distance and power condition.

• Archives of Pharmacal Research
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• v.22 no.4
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• pp.384-390
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• 1999

Thirty-four glutathione conjugates of 5,8-dimethoxy-1,4-naphthoquinones (DMNQ) were synthesized and their structure was determined. The yield of GSH conjugate was dependent on size of alkyl group; the longer the size of alkyl group was, the lower was the yield. It was also found that the length of alkyl side chain influenced the chemical shift of quinonoid protons; the quinonoid protons of 2-glutathionyl DMNQ derivatives with R=H to propyl, 6.51-6.59 ppm vs. other ones with R=butyl to heptyl, 6.64-6.68 ppm. this was explained to be due to a folding effect of longer alkyl group. Glutathione (GSH) reacted with DMNQ derivative first to form a 1,4-adduct (2- or 3-glutathionyl-1,4-dihydroxy-5,8-dimethoxynaphthalenes) and then the adduct was autooxidized to 2- or 3-glutathionyl-DMNQ derivatives. Moreover, GSH reduced DMNQ derivatives to their hydrogenated products. It was suggested that such an organic reaction might play an important role for a study of metabolism or toxicity of DMNQ derivative sin the living cells.

• Women's Health Nursing
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• v.4 no.2
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• pp.271-285
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• 1998

The purpose of this study is to explore and describe the experiences of postpartal woman, Korean postpatal care that Korean women experience afterbirth, to find the meaning of their lived experiences and to contribute to the base Korean maternal nursing. The method is to phenomenological through participant in depth interview. The subjects of this study were 8 women who are 1 week to less or over 100 days afterbirth. Their age rang from 22 to 33. All available data was collected from 26th of March 1988 to 10 of July 1998. A tape recorder was used with the permission of the subjects to prevent the loss of spoken information. The analysis of the data was made through Colaizzi's. The result of the study was as follow: There were eleven themes and 8 structures, Structure 1 : Acceptance to the traditional Sanhujori, Structure 2 : Powerlessness, Structure 3 : Disappointment and Being sorry, Structure 4 : Attachment as mother, Structure 5 : Anxiety on bring up, Structure 6 : Praying the well being of baby. Structure 7 : Negative body image 8 : Information seeking, Structure. In conclusion, nurses have to help Korean women afterbirth who are in difficulties physically, emotionally, socio-psychologically as direct caregivers and educators. As continually finding out the Korean postpartal care. Sanhujori, we can build the our original maternal nursing.

• Korean Management Science Review
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• v.28 no.3
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• pp.1-13
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• 2011

Hub-and-spoke transportation network is a powerful and useful network structure that takes full advantage of economies of scale on routes between hubs. In recent studies, the network structure is extended to hybrid hub-andspoke that allows direct transportation between spokes. In this study, we considered more extended network structure which is called hybrid multiple hub-and-spoke that has multiple hubs and allows direct transportation between spokes. We developed a mathematical optimization model for automotive service parts transportation planning under hybrid multiple hub-and-spoke network structure. The model suggests a long-term transportation route planning and a short-term vehicle assignment planning. The model is verified by simulation and validated in real world application to Hyundai Mobis automotive service parts transportation planning. From the simulation result, the model reduced the transportation cost about 24.7%, the total distance about 6.8% and the CO2 emissions about 8.8%. In real world application for 6 months from July to December 2010, the model reduced the transportation cost about 9.1% by changing the long-term transportation route without daily vehicle assignment planning.

• Bulletin of the Korean Chemical Society
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• v.16 no.6
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• pp.539-542
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• 1995

The crystal structure of K92-X (K92Al92Si100O384), a=25.128(1) Å, dehydrated at 360 ℃ and 2X 10-6 Torr, has been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd&bar{3} at 21(1) ℃. The structure was refined to the final error indices R1=0.044 and Rw=0.039 with 242 reflections for which I<3σ(I). In this structure, ninety-two K+ ions are located at the five different crystallographic sites. Sixteen K+ ions are located at the centers of the double six rings (site I; K(1)-O(3)=2.65(2) Å and O(3)-K(1)-O(3)=92.0(6)°). About twelve K+ ions lie at site I' in the sodalite cavity opposite double six rings (D6R's) and these K+ ions are recessed ca. 1.62 Å into the sodalite cavity from their O(3) plane (K(2)-O(3)=2.74(2) Å, O(3)-K(2)-O(3)=88.5(8)°). About thirty-two K+ ions are located at the site II in the supercage and these K+ ions are recessed ca. 1.20 Å into the supercage from their O(2) plane (K(3)-O(2)=2.64(2) Å, and O(2)-K(3)-O(2)=101(1)°). About twenty-two K+ ions lie at the site III in the supercage opposite 4-ring ladder and the remaining ten K+ ions lie at the site III' near the 4-ring ladder in the supercage (K(4)-O(4)=2.88(3) Å, O(4)-K(4)-O(4)=79.8(9)°, K(5)-O(4)=2.8(2) Å, and O(4)-K(5)-O(4)=68(5)°).

• Journal of Integrative Natural Science
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• v.8 no.1
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• pp.30-39
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• 2015

The crystal structure of the potential active 2-amino-4-(4-hydroxy-3-methoxyphenyl)-7, 9-dimethyl-5-oxo-4, 5, 6, 7-tetrahydropyrano [2, 3-d] pyrazolo [3, 4-b] pyridine-3-carbonitrile ($C_{21}H_{22}N_5O_6S$) has been determined from single crystal X-ray diffraction data. In the title compound crystallizes in the monoclinic space group P-1 with unit cell dimension a=8.1201(9)${\AA}$, b=12.2684(4)${\AA}$ and c=12.387(2)${\AA}$ [${\alpha}=69.573^{\circ}$, ${\beta}=12.168^{\circ}$ and ${\gamma}=76.060^{\circ}$]. In the structure the pyrazole, pyridine and pyran are almost coplanar each other. The crystal packing is stabilized by intermolecular C-H...O and N-H... O hydrogen bond interaction.