• Bulletin of the Korean Chemical Society
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• v.29 no.2
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• pp.305-308
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• 2008

We performed coupled-cluster calculations to determine the intermolecular interaction energy between two TiAu4 clusters. Our ab initio calculations predict that the binding energy is 2.89 eV, which is somewhat larger than the known binding energy of 2.0 eV for TiH4-TiH4. The intermolecular binding energy is relatively high, despite TiAu4 having all the attributes of a magic cluster. The favorable orbital interaction between occupied Au(6s) and unoccupied Ti(3d) orbitals leads to the strong dimeric interaction for TiAu4-TiAu4.

• Bulletin of the Korean Chemical Society
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• v.28 no.4
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• pp.662-666
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• 2007

Poly(vinyl butyral) (PVB) with different wt% water was studied gravimetrically as well as with 1H magic angle spinning (MAS) nuclear magnetic resonance (NMR). The composition of PVB samples changes during MAS NMR because of the centrifugal force. As MAS time progresses, initially free water was removed fast but bound water also was gradually depleted. More water was diminished at faster spinning speeds, longer spinning time, higher temperatures, and higher initial water contents. As water in PVB was reduced, the chemical shifts and line widths of different types of water and also those of PVB changed. Our results demonstrate that 1H MAS NMR carried out at 10 kHz in less than about 5 minutes is a convenient and sensitive technique to measure: (a) the content variations of different types of water in polymers, (b) the degree of the interaction of water and polymer, and (c) the molecular dynamics of the polymer. Our study can be extended to different soft polymers with other small molecules than water in them.

• Journal of the Korean Magnetic Resonance Society
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• v.20 no.3
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• pp.82-86
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• 2016

Ginseng is used as a medicinal ingredient. The quality control of species, age, origin and manufacturing process is important. The metabolome of ginseng about quality was studied in many reports. Almost studies carried out the extract of ginseng, however, the reproducibility cannot be obtained using extracted sample. In this study, powdery ginseng samples were analyzed using high resolution-magic angle spinning nuclear magnetic resonance (HR-MAS NMR)-based metabolomics except extraction step. Sample was measured three times using 600 MHz NMR spectrometer equipped with nano probe. Reproducibility can be enhanced using this method and the metabolic profiles of ginseng were identified and quantified.

• Journal of the Korean Society of Tobacco Science
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• v.6 no.2
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• pp.169-178
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• 1984

This study was conducted to investigate the influence of the topping time and height on the nonvolatile organic and higher fatty acid contents and the correlation among acid contents of tobacco plants. Within the topping time, the flowering (normal) stage of topping was the lowest in total analyzed acid (TAA), total nonvolatile organic acid (TNOA) and magic acid contents of NC2326, however, the highest in those of Burley 21 on 30 days after budding. Total higher fatty acid (THFA) and linoleic acid contents tended to be low with normal stage of topping. The lower the topping height, the lower the TAA, THFA and linoleic acid contents in middle and upper leaves (or NC2326 and Burley 21 were observed. On the other hand, the lower the topping height, the lower the TNOA and malic acid contents in middle and upper leaves for Burley 21 and upper leaves for NC2326 were found. There was a significant positive correlation between magic acid and TNOA contents. Similarly, TAA content showed a significant positive correlation with TNOA, oxalic acid and citric acid contents. But there was a negative correlation between malic acid and THFA contents. There were highly positive correlations among oleic acid, linoleic acid and THFA contents, respectively.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.199.1-199.1
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• 2012

TRIO-CINEMA(TRiplet Ionospheric Observatory-Cubesat for Ion, Neutron, Electron & MAgnetic field)는 지구근접공간에서의 미세 자기장 변화 및 중성입자의 검출을 목적으로 경희대학교와 UC Berkeley가 공동 개발하는 초소형위성이다. 초소형위성은 내부 공간이 협소하여 효율적인 공간배치 및 위성체발사 시 진동에도 견딜 수 있도록 harness가 제작되어야 한다. CINEMA는 OBC, EPS, 배터리, 수신기, IIB(Instrument Interface Board), MAGIC(MAGnetometer Imperial College) board, HVPS(High Voltage Power Supply)로 구성된 avionics bus와 MAGIC, STEIN(Supra Thermal Electron, Ion, Neutral)의 payload, Solar panel, UHF와 S-band 안테나로 구성되어 있다. Solar panel에서 생산된 전력은 EPS를 통해 배터리에 저장되고 PC104를 통해 avionics stack의 각 board로 전력이 분배된다. IIB는 탑재체 파트와 연결되어 이를 제어하고 HVPS에서 STEIN에 공급되는 고전압은 특수 와이어를 통해 연결되며 UHF 안테나와 S-band 안테나는 RF 케이블로 수신기와 송신기가 연결되어 있다. 각각의 harness는 케이블타이와 lacing tape로 위성체와 고정되며 커넥터는 고정 지지대를 제작하여 나사로 체결하였다. CINEMA에 적용된 harness는 진동시험과 열진공시험을 통해 harness와 시스템의 안정성이 검증 되었다.

• Korean Journal of Agricultural Science
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• v.40 no.4
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• pp.325-331
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• 2013

This experiment has been carried out to determine optimal culture conditions for the production of cut flowers and tubers of Calla (Zantedeschia 'Golden Affair' and 'Black Magic') in highlands. Treatments consisted of various levels of root zone environments, Results are as follows: Calla 'Golden Affair' were grown with different mulching materials such as Non-mulching, Black film, reflective film, Rice hull. Mulching materials resulted in no difference in the number of cut flowers but flower length was highest in reflective film. Calla 'Black Magic' were treated with various soil water content, soil type and watering time. Number of cut flowers and flower quality were greatest when the plants were watered at -80 kPa soil water content. No symptoms of soft rot (Erwinia carotovora) was observed at this soil water content. The occurrence of soft rot was observed with similar percentage according to soil type and the soil water content. When Calla 'Black Magic' were watered at the time of soil surface drying, growth was greater compared to others. Air temperature and PPF affected plant growth and photosynthesis. Photosynthetic rate was greatest at $25^{\circ}C$ and PPF $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, while lowest at $28^{\circ}C$ and PPF $800{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Soft rot did not occur without regard to dipping treatment (0, 5, 10, 24, 48 hours) when the day and night temperature were maintained at $25^{\circ}C$ and $20^{\circ}C$, respectively.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2003.10a
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• pp.143-151
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• 2003

• Korean Journal of Agricultural Science
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• v.43 no.1
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• pp.28-32
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• 2016

This experiment was carried out to determine optimal culture conditions for the production of cut flowers and tubers of Calla (Zantedeschia 'Black Magic') in highlands. To achieve the research purpose, growth of 'Black Magic' Calla influenced by tuber hardness (3.3 and $6.0kg/cm^2$), $GA_3$ concentration (0, 100 and $200mgL^{-1}$), duration of $GA_3$ treatment (24 hr, 12 hr and 30min before planting) were investigated. When tubers have high hardness, those were not severely injured by soft rot disease regardless of $GA_3$ concentrations and treatment durations. Tubers with low tuber hardness showed more than 90% of soft rot occurrence when treated with $200mgL^{-1}$ $GA_3$ for 24 hrs before planting. However, soft rot did not occur when tubers were treated with $200mgL^{-1}$ $GA_3$ for 12 hrs before planting. In conclusion, $GA_3$ treatment results showed soft rot occurrence statistically significant degree in accordance with the bulbs hardness. In addition, the yield of the cut flowers is the result received the greatest effect in accordance with the bulbs in size and appeared to not be determined in accordance with the $GA_3$ treatment concentration and hardness bulbs. To obtain flowers without soft rot symptom, tubers (as $6.0kg/cm^2$) should be completely dried after $GA_3$ treatment.

• 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.

• Restorative Dentistry and Endodontics
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• v.31 no.5
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• pp.390-397
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• 2006

The purpose of this study was to evaluate the accuracy and the consistency of four different electronic apex locators in an in vitro model. Fourty extracted premolars were used for the study. Four electronic apex locators (EAL) were Root ZX, Smarpex, Elements Diagnostic Unit (EDU), and E-Magic Finder Deluxe (EMF). After access preparation, the teeth were embedded in an alginate model and the length measurements were carried out at '0.5' and 'Apex' mark using four EALs. The file was cemented at the location of the manufacturers' instruction (Root ZX, EDU, EMF: 0.5 mark, SmarPex: Apex mark). The apical 4mm of the apex was exposed and the distance from the file tip to the major foramen was measured by Image ProPlus (${\times}100$). The distance from the file tip to the major foramen was calculated at 0.5 and Apex mark and the consistency of 0.5 and Apex mark was compared by SD and Quartile of Box plots. In this study, Root ZX and EMF located the apical constriction accurately within ${\pm}0.5 mm$ in 100%, whereas SmarPex and EDU located in 90% and in 70% respectively. For Root ZX and EMF, there was no significant difference between the consistency of 0.5 and Apex mark. However, for the EDU and SmarPex, Apex mark was more consistent than 0.5 mark. From the evaluation of the consistency in this study, for Root ZX and EMF, both 0.5 and Apex mark can be used as a standard mark. And for EDU and SmarPex, the Apex mark can be recommended to be used as a standard mark.