• 천문학회보
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• 제41권2호
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• pp.41.2-41.2
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• 2016

We perform three statistical studies on the physical properties and oscillations in the confined plasma such as a photospheric sunspot and confined coronal loop. From the statistical studies on the sunspot umbra and its oscillation, we find that (1) the total magnetic flux inside the umbra for the three groups increases proportionally with the powers of the umbral area and the power indices in the three groups significantly differ from each other; (2) the three groups have different characteristics in their umbral area, intensity, magnetic field strength, and Doppler velocity as well as their relationships; (3) the mean frequency of the umbral oscillations increases with the umbral mean magnetic field strength and height; (4) the time delay of the core intensity of Fe I absorption line relative to the continuum which are de-convolved with the frequency range higher than 3.5 mHz is mostly positive, implying that the photospheric umbral oscillations are likely upwardly propagating; (5) the umbral mean plasma beta ranges approximately 0.6-1.1 and does not vary significantly from pores to mature sunspots. From the comparative study on the quasi-periodic pulsations (QPPs) in the solar and stellar flares, (6) we find that the power index of the periods scaling the damping times observed in the stellar QPPs is consistent with that observed in the solar QPPs, suggesting that physical mechanisms responsible for the stellar QPPs are likely the magneto-hydrodynamic oscillation of solar coronal loops.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 C
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• pp.1555-1559
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• 1997

The thin films were obtained by plasma polymerization of phenyl isothiocyanate. Polymerizations were carried out in rf(13.56[MHz]) glow discharge generated in an inter-electrode capacitively coupled gas flow system. It was found that this monomer produces uniform films with a wide range of thicknesses, from hundreds of nanometers to tens of micrometers. The deposition rate appeared to be dependent on the substrate distance from the monomer inlet. The IR data revealed significant decrease in -NCS groups content in the polymer as compared with the monomer spectrum and indicated for the appearance of new absorption bands corresponding to the -CN and C-H aliphatic groups. The soluble fraction by GC was found to be composed of numerous low molecular-weight compounds.

• 분석과학
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• 제35권2호
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• pp.60-68
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• 2022

In this study, we developed and validated a sensitive analytical method to quantify baphicacanthin A in mouse plasma using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The standard calibration curves for baphicacanthin A ranged from 0.5 to 200 ng/mL and were linear, with an r² of 0.985. The inter- and intra-day accuracy and precision and the stability fell within the acceptance criteria. Besides, we investigated the pharmacokinetics of baphicacanthin A following its intravenous (5 mg/kg) and oral administration (30 mg/kg). Intravenously injected baphicacanthin A showed biphasic elimination kinetics with high clearance and volume of distribution values. Furthermore, baphicacanthin A showed a rapid absorption but low aqueous solubility (182.51±0.20 mg/mL), resulting in low plasma concentrations and low oral bioavailability (2.49 %). Thus, we successfully documented the pharmacokinetic properties of baphicacanthin A using this newly developed sensitive LC-MS/MS quantification method, which could be used in future lead optimization and biopharmaceutic studies.

• 대한전자공학회논문지
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• 제22권2호
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• pp.90-96
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• 1985

PECVD장비를 사용하여 PSG를 증착하고 막의 유전 및 보호막 특성을 조사하였다. X-선 형광분석으로 PSG내의 인 농도를 분석한 결과 약 8m/o에서 포화되었다. 인 함량에 대한 PSC의 적외선 홉수율, 식각속도 및 시트저항등의 변화도 비교하였다. APCVD와 PECV각에 대한 유전특성, 스텝 커버리지, 크랙저항과 게터링효과를 검토하였다. PECVD산화막은 비중 2.4g/㎤, 굴절율 1.53, 항복전장 11-13MV/cm의 값을 가졌고 크랙저항도 APCVD산화막 보다 우수하였다 2m/o의 인을 포함하는 PECVD PSG의 경우 양호한 스텝 커버리지와 게터링효과를 보였다. 공정변수에 대한 일련의 실험을 통하여 PECVD PSC 공정으로 보다 개선된 특성의 보초막을 얻을 수 있었다.

• 한국재료학회지
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• 제8권4호
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• pp.317-322
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• 1998

플라즈마 화학기상증착법에 의해 증착된 저유전율 SiOF박막의 물성 안정화를 위하여 증착후 $N_2O$플라즈마로 열처리함으로써 그 특성을 평가하였다. SiOF박막은 대기방치 및 열처리에 불안정한 성질을 가진다. SiOF 박막은 박막내의 F-Si-F 결합의 존재 때문에 흡습현상이 발생하며, 박막내의 F함량이 증가함에 따라 수분 흡수가 증가한다. 또한 열처리를 거치면서 F이 탈착되어 박막내의 F함량이 감소한다. $N_2O$플라즈마 열처리는 표면에 얇은 SiON층을 형성시킴으로써 박막을 안정화시키는데 효과적이었다. 그러나 장시간의 N/sun 2/O플라즈마 열처리는 유전율을 크게 증가시킨다. 따라서 $N_2O$플라즈마 열처리에 의한 유전율의 증가없이 물성을 안정화 시키기 위해서는, 대기방치나 열처리에 의한 안정화 효과를 유지하면서 $N_2O$플라즈마 열처리에 의한 유전율의 증가를 최소화시킬 수 있는 공정의 확립이 필요하다.

• Rapid Communication in Photoscience
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• 제4권3호
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• pp.50-53
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• 2015

$SnO_2$ thin films were deposited on fused silica substrate by pulsed laser deposition under transverse magnetic field. We have explored the effects of magnetic field and ablation laser wavelength on the optical properties of laser-induced plasma plume and structural characteristics of the deposited $SnO_2$ films. Optical emission from the plume was monitored using an optical fiber to examine the influence of magnetic field on the population of the excited neutral and ionic species and their decay with times after laser ablation. Also, we employed photoluminescence, x-ray diffraction, and UV-Vis absorption to characterize $SnO_2$ films.

• 한국전기전자재료학회논문지
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• 제21권4호
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• pp.362-367
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• 2008

We have Manufactured the low-k dielectric interlayer fabricated by plasma enhanced chemical vapor deposition (PECVD), The thin film of SiOCH is studied correlation between components and Dielectric constant. The precursor was evaporated and introduced with the flow rates from 16 sccm to 25 sccm by 1sccm step in the constant flow rate of 60 sccm $O_2$ in process chamber. The chemical characteristics of SiOCH were analyzed by measuring FT/IR absorption lines and obtained each dielectric constant measuring C-V. Then compare respectively. ILD of BTMSM/$O_2$ could have low dielectric constant about $k\sim2$, and react sensitively. Also dielectric constant could be decreased by the effects of decreasing $CH_3$ and growing Si-O-Si(C) after annealing process.

• 약학회지
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• 제55권3호
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• pp.260-266
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• 2011

Two types of water soluble lysine salts of ibuprofen were prepared and evaluated. Physicochemical properties for ibuprofen-l-lysinate (IBL-l), ibuprofen-dl-lysinate (IBL-dl) and ibuprofen (IB) were studied on melting point, specific ratation, UV spectra and $^1H$-NMR spectra. There were not differences between IBL-dl and IBL-l in UV spectra and $^1H$-NMR spectra. The pharmacokinetic parameters of IB were compared to those of its lysine salts (IBL-l and IBL-dl) after i.v. or oral administration at the dose of 50 mg/kg (calculated as IB). Total body clearance ($CL_t$) and area under the plasma concentration-time curve (AUC) were not different between IB group and IBL groups after i.v. administration. On the other hand, IBL-l and IBL-dl produced peak plasma concentrations ($C_{max}$) significantly ealier and higher than IB. Time to reach peak concentration ($T_{max}$) after IBL administration was lower than that after IB administration. There was no difference in AUC across all different groups (IB, IBL-l and IBL-dl) after oral administration. However, absorption rate constant ($k_a$) of IBL-l and IBL-dl were significantly increased than that of IB. These results indicated that the administration of IBL-l and IBL-dl may be advantageous if rapid and reliable onset of pain relief is required.

• 한국재료학회지
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• 제26권1호
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• pp.47-53
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• 2016

Silicon nitride ($SiN_x:H$) films made by plasma enhanced chemical vapor deposition (PECVD) are generally used as antireflection layers and passivation layers on solar cells. In this study, we investigated the properties of silicon nitride ($SiN_x:H$) films made by PECVD. The passivation properties of $SiN_x:H$ are focused on by making the antireflection properties identical. To make equivalent optical properties of silicon nitride films, the refractive index and thickness of the films are fixed at 2.0 and 90 nm, respectively. This limit makes it easier to evaluate silicon nitride film as a passivation layer in realistic application situations. Next, the effects of the mixture ratio of the process gases with silane ($SiH_4$) and ammonia ($NH_3$) on the passivation qualities of silicon nitride film are evaluated. The absorption coefficient of each film was evaluated by spectrometric ellipsometry, the minority carrier lifetimes were evaluated by quasi-steady-state photo-conductance (QSSPC) measurement. The optical properties were obtained using a UV-visible spectrophotometer. The interface properties were determined by capacitance-voltage (C-V) measurement and the film components were identified by Fourier transform infrared spectroscopy (FT-IR) and Rutherford backscattering spectroscopy detection (RBS) - elastic recoil detection (ERD). In hydrogen passivation, gas ratios of 1:1 and 1:3 show the best surface passivation property among the samples.

• Journal of Nutrition and Health
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• 제38권5호
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• pp.335-343
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• 2005

쥐에게 콩과 콩나물, 순수한 genistein을 함유되어 있는 genistein함량을 기준으로 동일하게 급여 (20mg/kg) 시켰을 때, 체내에서 흡수가 되는 속도는 soy, soy sprout, pure genistein군의 순이며 일반소화율은 soy sprout, pure genistein, soy군의 순이었다. 이로써 soy의 genistein은 쉽게 흡수되고 배설되며, 또한 전혀 흡수되지 않고 배설분으로 나오는 양도 세 그룹 중 가장 많은 것을 알 수 있었다. 이는 담즙 등으로 재순환되지 않는 양이 다른 그룹보다 많기 때문이라고 추정되었다. 따라서 생리기능상의 목적으로 isoflavone을 섭취하고자 할 때에는 콩보다는 콩나물형태로의 섭취가 타당할 것으로 생각되며 정확한 결과를 위해서도 사람이 섭식하는 상태의 콩과 콩나물의 isoflvones의 흡수율을 조사할 필요성이 있을 것으로 생각되었다.