• 한국응용과학기술학회지
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• 제36권1호
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• pp.165-173
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• 2019

국문 우주항공 분야에서 널리 쓰이고 있는 하이드라진[hydrazine, $N_2H_4$]은 로켓연료로 사용되는 대표적인 추진제이지만 환경에 유해하고 독성이 강하다는 단점이 존재한다. 따라서 친환경적이고 독성이 적은 추진제가 다양하게 개발되고 있다. 본 연구에서는 수산화아민[hydroxylamine, $NH_2OH$]을 출발물질로 하여, 질산[nitric acid, $HNO_3$]과 산-염기 반응을 통해 얻어지는 친환경 추진제 HAN[hydroxylammonium nitrate, $NH_3OHNO_3$]의 물리 화학적 특성에 대하여 적외선분광법을 이용하여 합성물의 조성, 화학구조 및 작용기를 관찰하였고, 열중량분석을 통해 HAN의 분해온도를 확인하였다. 이온 크로마토그래피를 통해 합성한 HAN에 함유되어 있는 질산이온의 함량을 측정하였다. 즉, N-H와 N-O의 IR peak가 $3161cm^{-1}$와 $1324cm^{-1}$에서 각각 나타나는 것을 통해 생성한 화합물이 HAN임을 확인하였고, pH 5-7 근처에서 합성한 HAN은 분해온도가 $120-140^{\circ}C$인 반면, pH 8 정도인 HAN은 분해온도가 $140^{\circ}C$ 이상임을 알 수 있었다. 한편, pH 6-7 사이에서 HAN을 합성하였을 때, 가장 높은 질산이온의 농도는 70%인 것으로 나타났다.

• 한국자기학회지
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• 제16권5호
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• pp.240-244
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• 2006

본 연구에서는 하지층으로 사용한 Mo(MoN)의 두께 변화에 따른 스핀밸브 구조의 자기적 특성과 열처리 결과를 비교 검토하였다. 사용된 스핀밸브는 Si기판/$SiO_2/Mo(MoN)(t{\AA})/NiFe(21\;{\AA})/CoFe(28\;{\AA})/Cu(22\;{\AA})/CoFe(18\;{\AA})/IrMn(65\;{\AA})/Ta(25\;{\AA})$ 구조이다. 또한 본 연구에서는 MoN 하지층을 Si기판에 증착하여 열처리후 특성을 분석하였다. MoN 박막의 질소량이 증가(5 sccm까지)할수록 비저항은 증가하였다. $600^{\circ}C$에서 열처리 후 측정한 XRD 결과를 보면 Si/Mo(MoN) 박막에서 규소화합물을 발견할 수 없었다. MoN을 하지층으로 사용할 경우 $300^{\circ}C$에서 열처리 후 측정한 XPS 결과를 보면 질소 유입량이 5 sccm인 경우가 질소 유입량이 1 sccm인 경우보다 안정적임을 알았다. Mo(MoN) 하지층을 사용한 경우 하지층 두께 변화($45{\AA}$)에 따라 자기저항비와 교환결합력의 변화는 소폭이었다. Mo 하지층의 열처리 온도별 자기저항비는 열처리 전 상온에서 7.0%이었고, $220^{\circ}C$ 열처리 때 7.5%로 증가하였다. 이후 열처리 온도를 $300^{\circ}C$까지 증가 시키면 자기저항비는 7.5%에서 3.5%로 감소하였고, 질소유입량이 변화(5 sccm까지)하여도 유사한 경향을 보였다.

• 공업화학
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• 제20권2호
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• pp.195-200
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• 2009

폴리에스터계 분체도료용 경화제로 사용하기 위하여 상업용 ${\beta}-hydroxyalkylamide$ (${\beta}-HAA$)의 주사슬에 cyclohexane 고리가 도입된 $N^1,N^1,N^4,N^4$-tetrakis(hydroxyethyl)cyclohexane-1,4-dicarboxamide ($Cy-{\beta}-HAA$)를 dimethyl trans-1,4-cyclohexanedicarboxylate과diethanolamine로부터 높은 수율로 합성하고 NMR, MS 및 FT-IR 스펙트럼으로 구조를 확인하였다. 합성된 $Cy-{\beta}-HAA$는 기존의 ${\beta}-HAA$에 비하여 열적 안정성이 우수할 뿐만 아니라, 폴리에스터 분체 도료의 경화제로 사용했을 시 ${\beta}-HAA$를 사용한 것에 비해 더 매끄러운 도막이 형성되었으며 도막 표면에 핀홀(pinhole)의 생성이 감소되었다.

• Bulletin of the Korean Chemical Society
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• 제29권1호
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• pp.187-190
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• 2008

The synthesis of a novel N,C,N-type pincer, bis(N-aryl)-2-bromoisophthalaldimine 2,6-(2,6-Et2PhN = CH)2C6H3Br (1) and Ni(1)Br (2) is described. They were characterized by elemental analysis and spectroscopic techniques (IR and 1H NMR). Attempted ethylene polymerization catalyzed by 2 has been futile, leading only to the formation of a small amount of oily oligomers.

• Macromolecular Research
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• 제13권1호
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• pp.14-18
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• 2005

Under irradiation in a microwave oven, six novel poly(amide-imide)s containing tetrahydropyrimidinone, tetrahydro-2-thioxopyrimidine moieties and trimellitic rings in their main chains were synthesized through the polycondensation reaction of N,N'-(4,4'-diphenylether)bis(trimellitimide) diacid chloride with six different derivatives of tetrahydropyrimidinone and tetrahydro-2-thioxopyrimidine in the presence of a small amount of a polar organic medium, such as o-cresol. The polycondensation proceeded rapidly and completed within 7-9 min, producing a series of new poly(amide-imide)s in high yield that showed inherent viscosities in the range 0.33-0.52 dL/g. These poly(amide-imide)s were characterized by elemental analysis, viscosity measurement, thermal gravimetric analysis, solubility test, and FT-IR spectroscopy. All of the polymers were soluble at room temperature in polar solvents such as N,N-dimethylacetamide, N,N-dimethylformamide, dimethylsulfoxide, tetrahydrofuran, and N-methyl-2-pyrrolidone.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.71-72
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• 2008

In this paper, the effect of thermal annealing on surface acoustic wave (SAW) properties of aluminum nitride (AlN) films were described. The films were fabricated on Si substrates by using Pulsed Reactive Magnetron Sputtering System. The SAW properties of $600^{\circ}C$-annealed AlN films were better than those of both $900^{\circ}C$-annealed AlN films and as-deposited ones. Their SAW velocities (Raleigh mode) and insertion losses were about 5212 m/s and 16.19 dB at $600^{\circ}C$ with the wavelength of $40{\mu}m$. The dependence of characteristics of AlN films on annealing conditions were also evaluated by using Fourier Transform-Infrared Spectroscopy (FT-IR) Spectrums and Atomic Force Microscopy (AFM).

• 한국의류학회지
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• 제22권4호
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• pp.515-524
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• 1998

The purpose of this study was to evaluate the thermal properties of ceramics coated nylon fabrics by determining far infra-red emissive properties, heat storage/release and thermal insulation. Far IR emissivity and emissive power were measured for 7~ 140n at 50'C . Three types of ceramics such as cordierite with $\alpha$-alumina, a-alumina with titanium oxide and a-alumina were chosen as specimens. Cordierite with $\alpha$-alumina was chosen to treat on the fabrics due to the good emissive properties on the fabrics. Add-ons and contents of ceramics were analyzed for ceramics and/or polyurethane coated fabrics. For the physical properties, thickness and air permeability were measured. Results showed a difference in the emissive property between ceramics themselves and ceramics coated fabrics. In the ambient temperature, there was no diffenence in emissivity among the different ceramics contents. Thermography showed that when the fabric was heated with the light, surface mean temperatures of fabrics were increased as the contents of ceramics increased, and the heat storage property was confirmed. In case of same thickness and air permeability, the thermal insulation value increased as the contents of ceramics increased because of increasing heat storage and Far IR reflectivity. So there were absorption and heat storage of ceramics for Far IR from human and reflection to human between ceramics coated fabrics and human.

• 한국지구과학회지
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• 제26권2호
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• pp.149-159
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• 2005

Simultaneous observations of MODIS (Moderate-resolution Imaging Spectroradiometer) onboard the Aqua and Terra satellites and weather station at ground near the Inchon International Airport (37.2-37.7 N, 125.7-127.2 E) during the period from December 2002 to September 2004 have been utilized in order to analyze the characteristics of satellite-observed infrared (IR) and visible data under fog and clear-sky conditions, respectively. The differences $(T_{3.7-11})$ in brightness temperature between $3.75{\mu}m\;and\;11.0{\mu}m$ were used as threshold values for remote-sensing fog (or low clouds) from satellite during day and night. The $T_{3.7-11}$ value during daytime was greater by about 21 K when it was foggy than that when it was clear, but during nighttime fog it was less by 1.5 K than during nighttime clear-sky. The value was changed due to different values of emission of fog particles at the wavelength. Since the near-IR channel at $3.7{\mu}m$ was affected by solar and IR radiations in the daytime, both IR and visible channels (or reflectance) have been used to detect fog. The reflectance during fog was higher by 0.05-0.6 than that during clear-sky, and varied seasonally. In this study, the threshold values included uncertainties when clouds existed above a layer of fog.

• 한국작물학회지
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• 제31권4호
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• pp.391-402
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• 1986

8개 품종과 한국의 8개 품종을 인도네시아 발리(남위 8$^{\circ}$42')와 한국 수원(북위 37$^{\circ}$16')에서 한국재배법과 인도네시아 재배법으로 시험한 결과는 아래와 같이 요약된다. 1. 지역간에 유의성이 나타나는 형질은 임실율과 천립중이었는데 지역효과는 두 형질이 서로 반대로서 수원에서는 임실율이 높았고 발리에서는 천립중이 높았다. 이는 임실율에서는 Japonica품종과 Indica품종이 발리보다 수원에서 높게 나타나는데 원인이 있으며 천립중은 Ind./Jap. 품종과 Japonica 품종이 대체로 발리에서 수원보다 크게 나타나기 때문이었다. 2. 재배법간의 차이는 건물중과 조고북에서만 유의적인 차이를 보였으며 이들 형질은 재식밀도가 낮고 시비양이 많은 한국재배법에서 높았다. 3. 두 지역에서 평균수량이 높았던 품종은 태백, 한강찰, 금강, IR36, IR50, Semeru 등 6개품종이 었으며 발리에서는 태백, 만석, 한강찰, 금강, IR50, IR36. Semeru, Cisadane 등 8개품종이었으며, 수원에서는 상남, 금강, TR50, IR36, Semeru 5개 품종이었다. 4. 경노계수 분석결과 수량구성요소의 수량 기여율은 발리에서는 수당립수, 주당수수, 임실률, 천립중 순이였으며 수원에서는 주당수수, 수당립수, 천립중, 임실률 순이였다. 5. 비교적 광지역 적당성을 보인 Ind./Jap.와 In-dica의 공시품종을 비교하여 보면 Indies 품종은 Ind./Jap. 품종보다 주당수수가 많은 편이고 Ind./Jap. 품종은 수당립수와 천립중이 Indies 품종보다 많은 경향을 보였다.

• Bulletin of the Korean Chemical Society
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• 제35권3호
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• pp.793-797
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• 2014

To develop a methodology for absolute determination of the surface areal density of functional groups on organic and bio thin films, medium energy ion scattering (MEIS) spectroscopy was utilized to provide references for calibration of X-ray photoelectron spectroscopy (XPS) or Fourier transformation-infrared (FT-IR) intensities. By using the MEIS, XPS, and FT-IR techniques, we were able to analyze the organic thin film of a Ru dye compound ($C_{58}H_{86}O_8N_8S_2Ru$), which consists of one Ru atom and various stoichiometric functional groups. From the MEIS analysis, the absolute surface areal density of Ru atoms (or Ru dye molecules) was determined. The surface areal densities of stoichiometric functional groups in the Ru dye compound were used as references for the calibration of XPS and FT-IR intensities for each functional group. The complementary use of MEIS, XPS, and FT-IR to determine the absolute surface areal density of functional groups on organic and bio thin films will be useful for more reliable development of applications based on organic thin films in areas such as flexible displays, solar cells, organic sensors, biomaterials, and biochips.