• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.381.1-381.1
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• 2014

In this study, we investigated the deposition behavior and the etch resistivity of plasma polymerized carbon hardmask (ppCHM) film with the variation of process temperature. The etch resistivity of deposited ppCHM film was analyzed by thickness measurement before and after direct contact reactive ion etching process. The physical and chemical properties of films were characterized on the Fourier transform infrared (FT-IR) spectroscope, Raman spectroscope, stress gauge, and ellipsometry. The deposition behavior of ppCHM process with the variation of temperature was correlated refractive index (n), extinction coefficient (k), intrinsic stress (MPa), and deposition rate (A/s) with the hydrocarbon concentration, graphite (G) and disordered (D) peak by analyzing the Raman and FT-IR spectrum. From this experiment we knew an optimal deposition condition for structure of carbon hardmask with the higher etch selectivity to oxide. It was shown the density of ppCHM film had 1.6~1.9 g/cm3 and its refractive index was 1.8~1.9 at process temperature, $300{\sim}600^{\circ}C$. The etch selectivity of ppCHM film was shown about 1:4~1:8 to undoped siliconoxide (USG) film (etch rate, 1300 A/min).

• 천문학논총
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• 제30권2호
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• pp.443-445
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• 2015

We provide results of near-infrared (NIR) spectroscopic observations of 83 nearby (0.002< z <0.48) and bright (K <14 mag) type 1 active galactic nuclei (AGNs). For the observations, we used the Infrared Camera (IRC) on AKARI allowing us to obtain the spectrum in the rarely studied spectral range of $2.5-5.0{\mu}m$. The $2.5-5.0{\mu}m$ spectral region suffers less dust extinction than ultra violet (UV) or optical wavelength ranges, and contains several important emission lines such as $Br{\beta}$ ($2.63{\mu}m$), $Br{\alpha}$ ($4.05{\mu}m$), and polycyclic aromatic hydrocarbon (PAH; $3.3{\mu}m$). The sample is selected from the bright quasar surveys of Palomar Green and SNUQSO, and AGNs with black hole (BH) masses estimated from reverberation mapping method. We measure the Brackett line properties for 11 AGNs, which enable us to derive BH mass estimators and investigate circum-nuclear environments. Moreover, we perform spectral modeling to fit the hot and warm dust components by adding photometric data from SDSS, 2MASS, WISE, and ISO to the AKARI spectra, and estimate hot and warm dust temperatures of ~1100K and ~220 K, respectively.

• 한국광학회지
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• 제22권3호
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• pp.122-128
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• 2011

하향신호를 위해서는 반사형 반도체 증폭기를 기반으로 한 광역선폭 광원 기술이 사용되었고 상향신호를 위해서는 파장 재사용 기술이 사용된 양방향 파장분할 다중화 수동 광네트워크 (WDM-PON)가 컴퓨터 시뮬레이션을 통해 구현되었다. 이 시스템에서 세가지 다른 종류의 광필터들이 비교되어 필터링의 영향이 분석되었고, 광 스펙트럼과 아이 다이어그램 (eye diagram)의 분석을 통해 파장 재변조 기술을 최적화 하였다. 최적화된 시스템 조건을 이용하여 양방향 신호의 전송 성능 곡선을 구하였고 이 시스템에서 반사에 의한 신호 왜곡의 영향을 분석하였다.

• 농업과학연구
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• 제22권2호
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• pp.151-155
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• 1995

Whatman carboxymethyl cellulose CM 32와 CM 70으로 부터 색소단으로서 trinitrophenyl를 함유하는 섬유소 유도체를 합성하였다. 먼저 diaminoethyl기를 부가하여 DAE-CM-celulose를 얻고 다시 DAE-CM기 부위를 2,4,6-trinitrophenyl기로 치환시켜 TNP-cellulose를 조제하였다. CM 32로 부터 얻은 TNP-cellulose는 입자의 평균 크기가 $44.6{\pm}9.6{\mu}mD{\times}127.9{\pm}22.5{\mu}mL$로서 CM 70의 것에 비하여 3분의 1 수준으로 길이가 짧은 반면 폭은 보다 팽윤된 상태이었으며, ${\varepsilon}$-TNP-lysine의 molar extinction coefficient $1.33{\times}10^4$을 적용하여 측정한 그램당 TNP의 몰분율은 0.68 millimole로서 CM 70의 것보다 5.6배 높았다. 섬유소 분해효소에 의한 TNP-cellulose의 분해산물인 TNP-oligosaccharide의 최대 흡수 파장 ${\lambda}_{max}$는 344 nm이었다. 이들 TNP-cellulose를 기질로 하여 Onozuka R-10 효소액을 반응시킨 결과 반응 생성물의 흡광도가 효소의 농도에 비례하는 관계를 나타내었으며 CM 32의 것을 사용한 경우에 그 기울기가 현저히 커서 낮은 효소 농도 범위에서도 감도가 높음을 확인하였다.

• 해양환경안전학회지
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• 제28권6호
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• pp.843-852
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• 2022

서남해안 대형저서무척추동물의 출현종 조성을 알아보기 위해 완도와 조도 18개 정점의 암반조간대에서 2014년부터 2021년까지 6~9월에 7회 조사하였다. 완도와 조도 암반조간대에서 출현한 대형저서무척추동물은 220종, 645개체/m²이었다. 종수는 완도 165종, 조도 167종으로 유사하였다. 평균밀도는 완도 726개체/m², 조도 564개체/m²로 완도가 다소 높았다. 종수는 정점 15에서 116종으로 가장 많았고, 밀도는 정점 7에서 1,664개체/m²로 높게 나타났다. 우점종은 좁쌀무늬총알고둥이 175개체/m²(27.1%)로 가장 우점하였고, 총알고둥 97개체/m²(15.1%), 갈고둥은 41개체/m²(6.3%)순으로 출현하였다. 기후변화지표종인 검은큰따개비가 15개 정점에서 출현하였고, 고유종인 털채찍해조숨이옆새우도 일부 정점에서 출현하였다. 국가적색목록(Red List) 중에 절멸위험(Extinction risk)의 가장 낮은 수준인 준위협의 모난어깨긴뿔고둥이 조도에서 출현하였다. 완도와 조도의 대형저서무척추동물은 우리나라 암반조간대 해안에서 나타나는 일반적인 특징을 보였다. 암반조간대 해안은 조위에 따른 노출 시간과 암반의 기질에 따라 수직적인 분포 경향을 보였으며, 완도와 조도는 좁쌀무늬총알고둥, 총알고둥, 조무래기따개비, 대수리 등 우점하여 서식지 분포 양상이 유사하였다.

• Journal of Information Display
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• 제3권1호
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• pp.6-10
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• 2002

We have synthesized a new green Ir(III) complex fac-tris-(3-methyl-2-phenyl pyridine)iridium(III) $Ir(mpp)_3$ and fabricated phosphorescent polymer light-emitting device using it as a triplet emissive dopant in PVK. $Ir(mpp)_3$ showed absorption centered at 388 nm corresponding to the $^1MLCT$ transition as .evidenced by its extinction coefficient of the order of $10^3{\cdot}$ From the PL and EL spectra of the $Ir(mpp)_3$ doped PVK film, the emission maximum was observed at 523 nm, due to the radiative decay from the $^3MLCT$ state to the ground state, confirming a complete energy transfer from PVK to $Ir(mpp)_3$. The methyl substitution has probably caused a red shift in the absorption and emission spectrum compared to $Ir(mpp)_3$. The device consisting of a 2 % doped PVK furnished 4.5 % external quantum efficiency at 72 $cd/m^2$ (current density of 0.45 $mA/cm^2$ and drive voltage of 13.9 V) and a peak luminance of 25,000 $cd/m^2$ at 23.4 V (494 $mA/cm^2$). This work demonstrates the impact of the presence of a methyl substituent at the 3-position of the pyridyl ring of 2-phenylpyridine on the photophysical and electroluminescence properties.

• 천문학회보
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• 제42권1호
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• pp.54.1-54.1
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• 2017

The UKIRT Wide-field Infrared survey for Fe+(UWIFE) is an unbiased survey of the first Galactic quadrant, with narrow-band filter centered on $1.644{\mu}m$. This survey covers $7^{\circ}$ < l < $62^{\circ}$ and |b| < $1.5^{\circ}$, where active interaction of stars and interstellar medium is expected. With median seeing of 0.8 arcsec, 5 - sigma detection limit of 18.7 mag and surface brightness limit of $8.1{\times}10^{-20}W\;m^{-2}arcsec^{-2}$, this survey gives an opportunity to statistically study Galactic [Fe II] - emitting sources for the first time. In order to identify Ionized Fe Objects (IFOs) in survey area systematically, we conducted visual inspection and automatic detection simultaneously. Total of ~300 extended IFOs are identified, most of them are found out to be part of supernova remnants (SNRs), young stellar objects, HII regions and planetary nebulae. The majority of IFOs are new discoveries which reveal shocked structures in high-extinction region. Spatial distribution of IFOs suggest that they trace Galactic structure. As a part of spectroscopic follow-up, we observed SNR candidate IFO J183740.829-061452.41 with IGRINS (Immersion Grating Infrared Spectrograph, Yuk+2010), mounted on 2.7m Harlan Smith telescope. This unknown arc-like, 6'-long IFO is coincident with inner part of radio continuum loop G25.8+0.2, which has been known as HII region. However, interior of this radio shell is filled with diffuse soft X-ray emission, and possible association of hard X-ray pulsar / pulsar wind nebula makes the nature of the IFO unclear. The H and K-band 2D spectrum shows shock-ionized [Fe II] filaments, which is apart from photoionized HII filaments. In this presentation we present basic statistics of newly identified IFOs, as well as the follow-up study of IFO J183740.829-061452.41.

• 한국재료학회지
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• 제24권8호
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• pp.417-422
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• 2014

In this study, we investigated localized surface plasmon resonance and the related coupling phenomena with respect to various geometric parameters of Ag nanoparticles, including the size and inter-particle distance. The plasmon resonances of Ag nanoparticles were studied using three-dimensional finite difference time domain(FDTD) calculations. From the FDTD calculations, we discovered the existence of a symmetric and an anti-symmetric plasmon coupling modes in the coupled Ag nanoparticles. The dependence of the resonance wavelength with respect to the inter-particle distance was also investigated, revealing that the anti-symmetric mode is more closely correlated with the inter-particle distance of the Ag nanoparticles than the symmetric mode. We also found that higher order resonance modes are appeared in the extinction spectrum for closely spaced Ag nanoparticles. Plasmon resonance calculations for the Ag particles coated with a $SiO_2$ layer showed enhanced plasmon coupling due to the strengthened plasmon resonance, suggesting that the inter-particle distance of the Ag nanoparticles can be estimated by measuring the transmission and absorption spectra with the plasmon resonance of symmetric and anti-symmetric localized surface plasmons.

• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3771-3776
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• 2010

The dynamics of the $CN^-$-ligated ferric cytochrome c (CytcCN) in $D_2O$ at 283 K following Q-band photoexcitation at 575 nm was observed using femtosecond time-resolved vibrational spectroscopy. The equilibrium vibrational spectrum of the CN stretching mode of CytcCN shows two overlapping bands: one main band (82%) at $2122\;cm^{-1}$ with $23\;cm^{-1}$ full width at half maximum (fwhm) and the other band (18%) at $2116\;cm^{-1}$ with $7\;cm^{-1}$ fwhm. The time-resolved spectra show bleaching of the CN fundamental mode of CytcCN and two absorption features at lower energies. The bleach signal and both absorption features are all formed within the time resolution of the experiment (< 200 fs) and decay with a life time of 1.9 ps. One transient absorption feature, appearing immediately red to the bleach signal, results from the thermal excitation of low-frequency modes of the heme that anharmonically couple to the CN fundamental mode, thereby shifting the CN mode to lower energies. The shift of the CN mode decays with a lifetime of 2 ps, equivalent to the time scale for vibrational cooling of the low-frequency heme modes. The other transient absorption feature, which is 3.3 times weaker than the bleach signal and shifted $27\;cm^{-1}$ toward lower energies, is attributed to the CN mode in an electronically excited state where the CN bond is weakened with a lowered extinction coefficient. These observations suggest that photoexcited CytcCN mainly undergoes ultrafast radiationless relaxation, causing photo-deligation of $CN^-$ from CytcCN highly inefficient. As also observed in $CN^-$-ligated myoglobin, inefficient ligand photodissociation might be a general property of $CN^-$-ligated ferric hemes.

• 천문학회보
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• 제36권1호
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• pp.88.2-88.2
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• 2011

The far-ultraviolet (FUV) continuum and spectral images of C IV and H2 emission lines for the region of Orion-Eridanus Superbubble (OES) are hereby presented and compared with the maps obtained in other wavelengths. While the region shows complex structures, consisting of hot gases and cold dust, a close examination reveals that the FUV emission in this region can be understood reasonably as the result of their interactions. We confirm the origin of most diffuse FUV continuum to be starlight scattered by dust, but we also find that the ionized gas also contributes 50-70% of the total FUV intensity in the regions of H_alpha arcs. We note the bright diffuse FUV continuum in the eastern part of the northern dust-rich region, and attribute it to the bright early-type stars more abundant in this region than in the west as the amount of dust itself does not seem to be much different across 'arc A' that separates the two regions. In addition, two P Cygni-type stars are identified in this eastern region and their peculiar spectral profiles around the C IV emission line are anifested in the scattered diffuse spectrum. Besides this, the C IV emission is generally enhanced at the boundaries of the hot X-ray cavities where thin dust regions are located, confirming the thermal interface nature of the origin of this cooling emission line. The morphology of the H2 emission shows a general correlation with dust extinction features but its intensity peaks are rather located in thin dust areas, off the peak dust regions. Furthermore, H2 emission is seen to be weak in the arc A region though the arc passes through the center of the dust-rich area. Hence, the H2 emission and dust features, together with those of X-ray and ion lines emissions, show stratified structure of arc A quite well, again confirming its thermal interface nature.