• Journal of the Korean Chemical Society
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• v.18 no.5
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• pp.329-340
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• 1974

Sulfadiazine, $C_{10}H_{10}N_4O_2S$, forms monoclinic crystals of space group $P21}c$ from a mixture of acetone and ethanol with $a=13.71{\pm}0.04,\;b=5.84{\pm}0.03,\;c=15.11{\pm}0.05{\AA},\;{\beta}=115.0{\pm}0.3^{\circ}$, and four molecules per cell. Three dimensional photographic data were collected with $CuK\alpha$ radiation. The structure was determined using Patterson and Fourier synthesis methods and refined by block diagonal least-squares methods with isotropic thermal parameter for all non-hydrogen atoms. The final R value was 0.15 for the 1517 observed independent reflections. The dihedral angle between the planes through the benzene ring and the pyrimidine ring is $76^{\circ}$. The conformational angle formed by the projection of the S-C(5) bond with that of N(1)-C(1) where the projection is taken along the S-N(1) bond is $77^{\circ}$. The imino nitrogen atom, N(1), and pyrimidine nitrogen atom, N(3), form intermolecular $N-H{\cdots}N$ hydrogen bond between the molecules related by center of symmetry. Amino nitrogen atom, N(4), forms two intermolecular $N-H{\cdots}O$ hydrogen bonds, with O(1) and O(2) atoms of different molecules separated by b. A two dimensional network of hydrogen bonds form infinite molecular sheets parallel to the (100) plane. Adjacent sheets are bound together by van der Waals forces.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.11
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• pp.1336-1342
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• 2017

The study examined and compared the physicochemical and characteristics of various rice brand varieties and private brand products on the market. The moisture content in the proximate composition of rice was 15.67~17.03%, crude protein content was 5.73~6.30%, crude lipid content was 0.38~0.95%, and crude ash content was 0.23~0.56 %. Ilmi and Ilpum had high moisture content, whereas Gosihikkari and Hopyeong had high crude protein content. In the Hunter's color value of rice flour, L value was 96.76~97.27, a value was -1.63~-0.63, and b value was 2.00~2.60. The WAI was 1.21~1.39, WSI was 0.63~0.93%, and amylose content was 14.63~20.86%, respectively; Gosihikkari and Ilmi showed the lowest values. The X-ray diffraction patterns of rice flours of all varieties showed an A shape. For the amylogram properties of rice flour, initial pasting temperature was $59.57{\sim}63.23^{\circ}C$, maximum viscosity was 569.00~718.67 B.U. (Brabender Units), breakdown was 303.00~423.67 B.U., and setback was 212.67~265.33 B.U.. For differential scanning calorimeter (DSC) of rice flour, onset temperature was $54.66{\sim}58.63^{\circ}C$, peak temperature was $65.87{\sim}68.14^{\circ}C$, end temperature was $73.37{\sim}75.54^{\circ}C$, and enthalpy was 1.98~2.95 cal/g. The rice varieties with high internal density and initial pasting temperature as well as low crude protein content, WAI, amylose content, and setback can be classified as good. Gosihikkari in Gyeonggi Province, Ilmi and Hopyeong in Jeollanam-do, and Samgwang in Chungcheongnam-do are among them.

• Journal of dental hygiene science
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• v.15 no.5
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• pp.577-584
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• 2015

The purpose of this study was to evaluate the effect of metal chloride infiltration treatment on color and strength changes of the yttria-stabilized tetragonal zirconia polycrystals (Y-TZP). Fifty disc specimens were prepared with a Y-TZP powder (ZPEX; Tosoh, Japan). Thirty different metal chloride solutions containing 0.03~0.08 wt% chromium and 0.03~0.07 wt% terbium ions were prepared. Presintered Y-TZP specimens were soaked in metal chloride coloring liquids for 3 minutes and sintered in air at $1,450^{\circ}C$ for 2 hours. The color of the specimens was measured with spectrophotometer and color difference (${\Delta}E^*$) was obtained based on the CIE $L^*$, $a^*$, $b^*$ color coordinate values. To evaluate the effect of metal chloride infiltration strength changes, the biaxial flexural test was performed at crosshead speed 0.5 mm/min. Colors of the sintered Y-TZP showed the colors of Vita shade guide A1, A2 and A3 with the infiltration of chromium and terbium chloride solutions. Density of the sintered Y-TZP increased by the infiltration of chromium and terbium chloride solutions. Bi-axial flexural strength of the sintered Y-TZP did not show statistically significant differences by the infiltration of chromium and terbium chloride solutions (p>0.05). Chromium and terbium chloride did not affect the crystal phase of zirconia, and all specimens showed tetragonal phase. Accordingly, this study suggests that chromium and terbium chlorides can make colored zirconia while adding in a liquid form. The color of colored zirconia differ from that of vita shade guide but it can use all ceramic restoration as substructure in dental clinic.

• The Journal of Korean Society for Radiation Therapy
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• v.33
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• pp.35-46
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• 2021

Purpose : By comparing and analyzing treatment plans using abdominal compression and The Continuous Positive Air Pressure(CPAP) during SABR of lung cancer, we try to contribute to the improvement of radiotherapy effect. Materials & Methods : In two of the lung SABR patients(A, B patient), we developed a SABR plan using abdominal compression device(the Body Pro-Lok, BPL) and CPAP and analyze the treatment plan through homogeneity, conformity and the parameters proposed in RTOG 0813. Furthermore, for each phase, the X, Y, and Z axis movements centered on PTV are analyzed in all 4D CTs and compared by obtaining the volume and average dose of PTV and OAR. Four cone beam computed tomography(CBCT) were used to measure the directions from the center of the PTV to the intrathoracic contacts in three directions out of 0°, 90°, 180° and 270°, and compare the differences from the average distance values in each direction. Result : Both treatment plans obtained using BPL and CPAP followed recommendations from RTOG, and there was no significant difference in homogeneity and conformity. The X-axis, Y-axis, and Z-axis movements centered on PTV in patient A were 0.49 cm, 0.37 cm, 1.66 cm with BPL and 0.16 cm, 0.12 cm, and 0.19 cm with CPAP, in patient B were 0.22 cm, 0.18 cm, 1.03 cm with BPL and 0.14 cm, 0.11 cm, and 0.4 cm with CPAP. In A patient, when using CPAP compared to BPL, ITV decreased by 46.27% and left lung volume increased by 41.94%, and average dose decreased by 52.81% in the heart. In B patient, volume increased by 106.89% in the left lung and 87.32% in the right lung, with an average dose decreased by 44.30% in the stomach. The maximum difference of A patient between the straight distance value and the mean distance value in each direction was 0.05 cm in the a-direction, 0.05 cm in the b-direction, and 0.41 cm in the c-direction. In B patient, there was a difference of 0.19 cm in the d-direction, 0.49 cm in the e-direction, and 0.06 cm in the f-direction. Conclusion : We confirm that increased lung volume with CPAP can reduce doses of OAR near the target more effectively than with BPL, and also contribute more effectively to restriction of tumor movement with respiration. It is considered that radiation therapy effects can be improved through the application of various sites of CPAP and the combination with CPAP and other treatment machines.

• Bulletin of the Korean Chemical Society
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• v.31 no.7
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• pp.1937-1940
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• 2010

Ionic liquids with halide anions were prepared and the dependency of halide anions on the $SO_2$ solubility of ILs was investigated. The study shows that the $SO_2$ solubility of ionic liquids lies in the range 1.91~2.22 $SO_2$/ILs mol ratio. $SO_2$ solubility in ionic liquids with varying halide anions follows the order Br > Cl > I. Theoretical investigation was also conducted at the B3LYP level using the Gaussian 03 program. From the theoretical consideration of the interaction between $SO_2$ and [EMIm]X (where X = Cl, Br, and I), it has been proposed that primary interaction of halide occurs with $C_2$-H of the imidazolium and S of $SO_2$. Experimental results further shows that the absorption and desorption process of $SO_2$ in ILs was reversible by the three cycles of the absorption at $50^{\circ}C$ and desorption at $140^{\circ}C$. The reversibility of $SO_2$ absorption was confirmed by FT-IR studies.

• Bulletin of the Korean Chemical Society
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• v.23 no.11
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• pp.1527-1530
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• 2002

1,12-diazacyclodocosane-2,11-dione was first isolated from a plant Phyllanthus niruri Linn. Its structure has been determined by means of spectroscopy methods and X-ray crystallography. Two peptide groups in the big ring (lactam) are the main factors influencing intermolecular contacts. The hydrogen-bond interaction of these hydrophilic groups is observed in the crystal structure. Meanwhile, C-H···O hydrogen bonds in molecules contribute to the formation of the whole crystal. These two kinds of hydrogen-bond form six- member rings among molecules. This compound crystallizes in the triclinic space group P-1 with a= 9.588(1) $\AA$, b= $9.850(1)\AA$, c = $11.810(1)\AA$, $\alpha=$ 68.18(1)$^{\circ}C$ , $\beta=$ 84.98(1), $\gamma$ = 86.03(1)$^{\circ}C$ , V = $1030.66(17)\AA3$ , Z = 2. A disorder of five-member carbon chain in the whole ring is observed in the title compound. The bond angle 105.8(4) is determined for a extreme configuration C(14)-C(15)-C(16), and 117.7(10) for another extreme configuration C(14')-C(15')-C(16'). In this crystal, two molecules are tied each other by short intermolecular hydrogen bonds, the oxygen atom being tied by hydrogen bond to nitrogen atom of another two molecules. The NMR and IR spectral data coincides to the structure of the compound.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.04a
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• pp.618-626
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• 2011

Recent development of related technologies and efficient utilization of the entire country for the purpose of railway construction, and plans are being accelerated. the railway noise has been improved by increasing the high speed railway station, and accelerating the existing trains. Nord2000 which is an overseas noise prediction equation could not be applied directly to the domestic railway vehicles. So the specific vehicles in the Nordic countries which is a similar specification to domestic trains should be selected. Nord2000's accuracy was compared to Schall03, CRN's. Prediction of Ground impedance and Roughness class were carried out at different. In this paper, the result of selected vehicles for Nord2000 was as follows. S-1aX2 was for express trains, N-$^*2c$-3b was for Mugunghwa, S-Pass/wood was for Saemaul, N-4a was for freight trains, N-3a was for subway, the calculation time for Nord2000 took longer than others, in addition, Ground absorption was indispensable to calculate a noise map for Nord2000. As a result, CRN's prediction noise levels at Wonju-si was closest to the measurements. However, the predicted noise levels of Nord2000 was the most accurate.

• Bulletin of the Korean Chemical Society
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• v.20 no.8
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• pp.948-952
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• 1999

Electrophilic substitutions on β-position of 2,5-dimethyl pyrrole have been investigated theoretically. The electron donating methyl groups enrich electron densities on C-3, C-4 positions and π* interactions with methyl groups substituted on C-2 and C-5 positions pushed up the HOMO level of the pyrroles consequently induce rapid substitutions on C-3, C-4 sites. Substitution of phenylsulfonyl group on nitrogen stabilized LUMO levels through weak π bonding interactions. Unexpected deoxidation reaction underwent on the sulfonyl group substituted at C-3 position. The structures were solved by X-ray crystallography. Meanwhile, gas phase HF/6-31G* and density functional method (B3LYP/6-31G*) calculations gave favorable energies for 1-phenylsulfinyl pyrrole (6) over 3-phenylsulfinyl pyrrole (5) by 3.6-4.7 kcal/mol which is contrary to the experimental result. However the methods involve the effects of molecular polarizability and solvent, molecular dynamics (MD) and ab-initio self consistent reaction field (SCRF) calculations showed same trend as experiments. According to MD calculations, compound 5 is more stable than compound 6 by 4.15 kcal/mol and the SCRF, HF/6-31G* calculations gave more stable energy value for structure 5 than 6 by 0.03 kcal/mol.

• Korean Journal of Food Science and Technology
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• v.10 no.2
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• pp.181-188
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• 1978

To study on the changes in saponins from callus mass by tissue culture, the callus was derived from the petiole of Korean Ginseng (Panax Ginseng C.A. Meyer) and cultivated on Murashige and Skoog's agar medium supplemented with 2.4-dichlorophenoxyacetic acid and kinetin for 8 months. Then, well-grown callus was analyzed for its components estimation. The results obtained are as follows: (1) When saponins isolated from callus mass were chromatographed on a silca gel plate, and determined by the thinchrograph TFG-10, the ratio of Rb, c to Rg(f) in saponins was 2.16 to 1 and Rb, c, d to Re, g (f) was 1 to 1.63, while in the case of saponins from the root of Panax Ginseng grown by soil culture, the ratio of Rb, c to Rg(f) was 1.03 to 1 and the ratio of Rb, c,d to Re, g(f) was 1 to 1.17. (2) Sapogenins were obtained from the hydrolysates of saponins, and determined by thinchrograph TFG-10. The ratio of panaxadiol to panaxatriol in sapogenins from callus saponins was 2.66 to 1, while the ratio of panaxadiol to panaxatriol in sapogenins from ginseng root saponins was 1.86 to 1. From the results above mentioned, we concluded that the relative contents of sapogenins in saponins from callus mass by tissue culture were different from those in saponins from ginseng root by soil culture.

• Nuclear Engineering and Technology
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• v.54 no.8
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• pp.3051-3058
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• 2022

In the present work, untreated Iraqi sand with grain sizes varied between 100 and 200 ㎛ was used to produce a colored glass sample that has shielding features against the low gamma-ray energy. Therefore, a weight of 70-60 wt % sand was mixed with 9-14 wt% B₂O₃, 8-10 wt% Na₂O, 4-6 wt% of CaO, 3-6 wt% Al₂O₃, in addition to 0.3% of Co₂O₃. After melting and annealing the glass sample, the X-ray diffraction spectrometry was applied to affirm the amorphous phase of the fabricated glass samples. Moreover, the X-ray dispersive energy spectrometry was used to measure the chemical composition, and the MH-300A densimeter was applied to measure the fabricated sample's density. The Makishima-Makinzie model was applied to predict the mechanical properties of the fabricated glass. Besides, the Monte Carlo simulation was used to estimate the fabricated glass sample's radiation shielding capacity in the low-energy region between 22.1 and 160.6 keV. Therefore, the simulated linear attenuation coefficient changed between 10.725 and 0.484 cm^-1, raising the gamma-ray energy between 22.1 and 160.6 keV. Also, other shielding parameters such as a half-value layer, pure lead equivalent thickness, and buildup factors were calculated.