• Natural Product Sciences
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• v.20 no.2
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• pp.95-101
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• 2014

Five lignan glycosides, seven megastigmane glycosides, and seven phenolic compounds were isolated by repeated column chromatography from the MeOH extract of Salsola komarovii. Their structures were determined to be lariciresinol-9-O-${\beta}$-$\small{D}$-glucopyranoside (1), alangilignoside C (2), conicaoside (3), (+)-lyoniresinol 9'-O-${\beta}$-$\small{D}$-glucopyranoside (4), (8S,8'R,7'R)-9'-[(${\beta}$-glucopyranosyl)oxy]lyoniresinol (5), blumenyl B ${\beta}$-$\small{D}$-glucopyranoside (6), blumenyl A ${\beta}$-$\small{D}$-glucopyranoside (7), staphylionoside D (8), icariside $B_2$ (9), (6R,9S)-3-oxo-${\alpha}$-ionol ${\beta}$-$\small{D}$-glucopyranoside (10), 3-oxo-${\alpha}$-ionol 9-O-${\beta}$-$\small{D}$-apiofuranosyl-($1{\rightarrow}6$)-${\beta}$-$\small{D}$-glucopyranoside (11), blumenol B 9-O-${\beta}$-$\small{D}$-apiofuranosyl-($1{\rightarrow}6$)-${\beta}$-$\small{D}$-glucopyranoside (12), benzyl 6-O-${\beta}$-$\small{D}$-apiofuranosyl-${\beta}$-$\small{D}$-glucopyranoside (13), canthoside C (14), tachioside (15), isotachioside (16), biophenol 2 (17), 2-(3,4-dihydroxy)-phenyl-ethyl-${\beta}$-$\small{D}$-glucopyranoside (18), and cuneataside C (19) by spectroscopic methods. All the isolated compounds 1 - 19 were reported from this source for the first time. Compounds 2, 3 and 6 upregulated NGF secretion to $118.8{\pm}3.6%$, $128.2{\pm}9.3%$ and $111.1{\pm}7.1%$ without significant cell toxicity.

• Journal of the Korean Chemical Society
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• v.36 no.6
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• pp.812-817
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• 1992

Fluorometholone $(C_{22}H_{29}FO_4)$, M.W. = 376.5, monoclinic, $P2_1$, a = 6.410(4), b = 13.431(3), c = 10.996(3)$\AA$, $\beta$ = 92.81$(3)^{\circ}$, Z = 2, F(000) = 404, T = 292K, $\lambda$(Mo-$K_\alpha$) = 0.7107$\AA$, $\mu$ = 0.57$cm^{-1}$, $D_c$ = 1.32 $g/cm^3$, $D_m$ = 1.31 $g/cm^3$ and final R = 0.032 for 1769 observed reflections. All bond lengths and angles are within normal limits. Ring A is almost planar, B ring has a highly symmetrical chair conformation and C ring is in a distorted chair conformation. Ring D is in a intermediate conformation between 13$\alpha$-14$\beta$-half-chair and 13$\alpha$-envelope. Torsion angle C(16)-C(17)-C(20)-O(20) of $-7.9^{\circ}$ is a lower value than those of $-31.9^{\circ}$ and $-16.5^{\circ}$ for 9-fluoro-6-methylprednisolone I and II respectively.

• Journal of the Korean Chemical Society
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• v.32 no.4
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• pp.297-300
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• 1988

Ammonium p-methylbenzenesulfonate, $C_7H_11NO_3S$, Mr = 189.23, orthorhombic, space group $Pna2-1$, a = 20.406(4), b = 6.271(1), c = 7.067(2)${\AA}$, V = 904.19 ${\AA}^3$, Z = 4, $D_x$ = 1.39, $D_m =1.38g{\cdot}cm^{-3}$, ${\lambda}(M_o K_{\alpha})$ = 0. 71069 ${\AA}$, ${\mu}=3.1 cm^{-1}$, T = 298K, F(000) = 400, final R = 0.057 for 994 unique observed reflections with I > $16{\sigma}(I)$. The methylbenzene portion including the sulfur atom is nearly planar. Between the $SO_3$ groups and the ammonium ion, there are three unique hydrogen bonds; two of which make the anions linked along the c-axis and the remaining one along the b-axis. These hydrogen bonds make two-dimensionally hydrogen-bonded molecular layers. Among these hydrophilic layers, the methylbenzene moieties cluster together to form hydrophobic layers.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.277-280
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• 2011

We studied the relative stability and atomic structure of five $C_{20}^{2+}$ isomers obtained by two-electron ionization of a $C_{20}$ cage (the smallest fullerene). All the isomers are bond-stretch isomers, i.e., they differ in bond length. In particular, in one of the isomers with Ih symmetry, all the bond lengths are equal. Full geometry optimizations of the dipositive ion $C_{20}^{2+}$ were performed using the hybrid density functional (B3LYP/6-31G(d)) methods. All isomers were found to be true minima by frequency analysis at the level of B3LYP/6-31G(d) under the reinforced tight convergence criterion and a pruned (99,590) grid. The zero-point correction energy for the cage bond-stretch isomers was in the increasing order $D_{2h}<C_{2h}<C_2<T_h<I_h$ of $C_{20}^{2+}$. The energy difference among the isomers of cage dipositive ions was less than that among neutral cage isomers. Our results suggest that these isomers show bond-stretch isomerism and that they have an identical spin state and an identical potential energy curve. Although the predominant electronic configurations of the isomers are similar, the frontier orbital characteristics are different, implying that we could anticipate an entirely different set of characteristic chemical reactions for each type of HOMO and LUMO.

• Progress in Superconductivity and Cryogenics
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• v.21 no.2
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• pp.36-39
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• 2019

Effects of the spherically shaped Ge and the rod-like carbon-coated Ge on the superconducting properties of $MgB_2$ were investigated. Pure Ge and carbon-coated Ge nano-powders were synthesized under the different amount of $CH_4$ (0 to 5 kPa) by using DC thermal plasma method. When the $CH_4$ was added ~100 nm sized Ge with a spherical shape changed to rod-like morphology with a diameter of ~30-70 nm and a length of ~400-500 nm. Also it was confirmed that thin carbon layers of a few nanometers were formed along the rod length and the agglomerated carbons were found on the edges of rods. Pure spherical Ge and Ge/C rods were mixed and milled with Mg & B precursor to form the doped $MgB_2$ bulk samples by the solid-state reaction method. Almost no change of $T_c$ was noticed for the pure Ge-added $MgB_2$, whereas $T_c$ was found to decrease with the Ge/C-added $MgB_2$ samples. It was found that the pure spherical Ge showed to have a negative effect on the flux pinning of $MgB_2$. However, Ge/C rods can enhance the flux pinning property of $J_c$ due to the coated carbon on Ge rods.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.7
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• pp.646-652
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• 2013

EU's Galileo project is a market-based GNSS (Global Navigation Satellite System) that is under development. It is expected that Galileo will provide the positioning services based on new technologies in 2020s. Because Galileo E1 signal for OS (Open Service) shares the same center frequency with GPS L1 C/A signal, CBOC (Composite Binary Offset Carrier) modulation scheme is used in the E1 signal to guarantee interoperability between two systems. With E1 signal consisting of a data channel and a pilot channel at the same frequency band, there exist several options in designing signal acquisition for Assisted-Galileo receivers. Furthermore, compared to SNR worksheet of Assisted-GPS, some factors should be examined in Assisted-Galileo due to different correlation profile and code length of E1 signal. This paper presents SNR worksheets of Galileo E1 signals in E1-B and E1-C channel. Three implementation losses that are quite different from GPS are mainly analyzed in establishing SNR worksheets. In the worksheet, hybrid long integration of 1.5s is considered to acquire weak signal less than -150dBm. Simulation results show that the final SNR of E1-B signal with -150dBm is 19.4dB and that of E1-C signal is 25.2dB. Comparison of relative computation shows that E1-B channel is more profitable to acquire the strongest signal in weak signal environment. With information from the first satellite signal acquisition, fast acquisition of the weak signal around -155dBm can be performed with E1-C signal in the subsequent satellites.

• Reproductive and Developmental Biology
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• v.28 no.4
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• pp.227-233
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• 2004

This study was conducted to investigate the effect of various addition and exclusion time of glucose (Control: no addition, A: 24～72 h, B: 24～48 h, C: 48～72 h, D: 0～72 h, E: 0～48 h, F: 0～24 h and 48～72 h, G: 0～24 h) on embryonic developmental capacity of 2-cell embryos in mice. Developed blastocysts were assessed for mean cell number by differential staining. The zona-intact blastocyst (ZiB) rates were higher (p<0.05) in group B than control. However, the zona-escape blastocyst (ZeB) rates were not significantly different in all groups. At 72 h, total blastocyst (ZiB + ZeB) formation rates were not significantly different in all groups. The mean cell number was not significantly different among all groups. The inner cell mass (ICM) cell number was higher (p<0.05) in group F than control, group A, B and G. The trophectoderm (TE) cell number was higher (p<0.05) in control than group A and D. The %ICM was higher (p<0.05) in group C, D and F than control. The ICM : TE ratio was not significantly different in all groups. Between control and glucose group, no significant difference was observed in the total blastocysts (ZiB + ZeB) formation rates. Also, no significant difference was observed in the mean cell number, ICM cell number and ICM : TE ratio. However the TE cell number was higher (p<0.05) in control than glucose group and %ICM was higher (p<0.05) in glucose group than control. In conclusion, glucose added in culture medium was not inhibitory on blastocyst formation but glucose added for 48 ～72 h in culture medium increases %ICM of blastocysts in mice.

• Journal of Photoscience
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• v.9 no.2
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• pp.110-113
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• 2002

We demonstrate here a dynamic structure of bacteriorhodopsin (bR) as revealed by $^{13}$ C NMR studies on [3_$^{13}$ C]_,[1-$^{13}$ C]Ala- and/or Val-labeled wild type and a variety of site-directed mutants at ambient temperature. For this purpose, well-resolved (up to twelve) I$^{13}$ C NMR peaks were assigned with reference to the displacement of peaks due to the conformation-dependent I$^{13}$ C chemical shifts and reduced peak-intensities due to site-directed mutations. Revealed bR structure was not rigid as anticipated from 2D crystals of hexagonal array but a dynamically heterogeneous, undergoing a variety of local fluctuations depending upon specific site with frequency range of 10$^2$ -10$^{8}$ Hz. In particular, dynamics- dependent suppression of peaks turned out to be very sensitive to the motion of 10$^{-4}$ s and 10$^{-5}$ s interfered with frequency of magic angle spinning and proton decoupling, respectively. It is also noteworthy that such dynamic feature is strongly dependent upon the manner of 2D crystalline packing: $^{13}$ C NMR peaks of monomeric bR yielded either highly broadened or completely suppressed signals, depending upon the type of $^{13}$ C-labeled amino-acid residues.

• Journal of Korean Society of Transportation
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• v.9 no.1
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• pp.29-46
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• 1991

The purpose of this study is to develop a parking behavior model in prior step for solv-ing parking problems in Pusan C. B. D. The results of this study are as follows; In the C. B. D of Pusan the peak parking time is between 2 and 3 o'clock P. M., and the average parking duration is 237 minutes. It means the use of parking lots is very ineffi-cient. Hence in order to shorten the parking duration, it is very urgent for drivers to chan-ge parking attitude. The walking distance from the parking lots to his destination is below 300∼500m, so the establishment of parking areas and the arrangement of parking lots in C. B. D should be planned on the base of the above walking distance. The model distinguishing between legal and illegal parking behaviors is derived from the binary decision model. The selected model has the correlation rate, η2=0.505 which is relatively high value This result shows that the detetminating judgement on the legal and illegal parking behavior is influenced mutually such factors as driver's occupation parking purpose monthly income distance to his destination averaged parking duration and age.

• Journal of the Korean Society for Heat Treatment
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• v.21 no.1
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• pp.26-32
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• 2008

Effects of annealing treatment on microstructure and mechanical property of co-sputtered TiNi thin films were studied. As-deposited films showed amorphous state. However, above annealing temperature of $500^{\circ}C$ martensite phase (B19'), precipitate phase ($Ti_2Ni$) and a small amount of parent phase ($B_2$) were present, and phase transformation behaviors were three multi-step phase transformations $B19^{\prime}{\rightarrow}B_2$ and $B_2{\rightarrow}R-phase$ and $R-phase{\rightarrow}B19^{\prime}$. Increase of martensite transformation temperature, increase of microhardness and Young's modulus of TiNi films annealed above $500^{\circ}C$ were discussed in terms of precipitate phase.