• Aerospace Engineering and Technology
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• v.6 no.2
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• pp.104-110
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• 2007

Analyzed is the spectral response profile specification used for the infrared (IR) channels of the meteorological imagers of GOES series geostationary satellites. The variation characteristics of effective wavelength and effective input radiance due to the change of the spectral response function profile within the imager performance specification are analyzed in order to propose how to understand the spectral response specification. As an analysis approach, at first a center symmetrical spectral response function and 4 worst case spectral response functions are selected within the spectral response specification, and then effective wavelength and effective input radiance are calculated for each spectral response function. As a result, the maximum allowable ranges of effective wavelength and effective input radiance are provided per the spectral response specification.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.7
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• pp.426-439
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• 2017

This review summarizes advantage and limitation in infrared spectroscopy and computational chemistry to understand rhizospheric interaction among organic acids, oxyanions and metal oxides. Since organic acids and metal oxides determine dynamics of oxyanions in the soil environment, knowledge of fundamental mechanisms is a prerequisite for understanding the interactions at soil-water interface. Attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR) is a powerful tool to measure the interfacial reactions. However, the ATR-FTIR measurements are abstruse, because the optical characteristics for measurements are variable depending on the experimental setup. In addition, spectral overlapping is a primary obstacle to the analysis of the interfacial reaction; thus, it is essential to detect and to deconvolute bands for signal interpretation. In this review, we expained the fundamental principle for spectrum processing, and four band identification methods, such as derivative spectroscopy, two-dimension correlation spectroscopy, multivariate curve resolution, and computational chemistry with example of aqueous phosphate speciation. As a result, spectrum processing and computational chemistry improved interpretation and spectral deconvolution of overlapped spectra in relatively simple systems, but it was still unsatisfactory for the problems in more complexed system like nature. Nevertheless, we believed that our challenge would contribute practically to develop adequate analytical procedure, signal processing and protocols that could help to improve interpretation and to understand the interfacial interactions of oxyanions in natural systems.

• Proceedings of the Korea Contents Association Conference
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• 2011.05a
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• pp.447-448
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• 2011

오래전부터 적외선은 문서감정 분야에서 사용했으나, 대부분 필기구의 분광반사 차이를 이용한 문서의 위변조에 집중되었을 뿐, 문서를 작성한 필기구들의 사용 순서에 대한 분석에는 이용하지 않았다. 문서작성의 순서를 분석하기 위해서는 보통 현미경으로 필적을 확대하여 분석하지만, 상황에 따라 분명치 않은 경우도 있다. 따라서 본 연구에서는 필기구들의 분광반사 차이를 이용하여 필기구들이 겹친 영역을 분석함으로서 문서작성에 사용한 필기구들의 사용 순서를 쉽게 판단할 수 있는 방법을 제안하고 있다. 이 방법은 필기구 사용 순서에 따라 법적인 해석에 대한 논쟁이 있을 수 있는 보험계약서 등에 적용이 가능할 것으로 기대한다.

• 방재와보험
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• s.114
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• pp.36-41
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• 2006

전기화재의 발생 원인을 과학적으로 분석하고 향후 예방을 위한 자료로 활용하기 위해 계기용 변성기(계기용 변압변류기 : MOF)의 화재 확산 패턴 및 조직 분석, 성분 해석, 적외선 분광분석 등을 통해 사고의 원인을 분석해 보고자 한다.

• Journal of the Mineralogical Society of Korea
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• v.13 no.1
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• pp.37-43
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• 2000

Fourier transform 적외선 분광기를 사용하여 원적외선 (<200 cm-1) 영역과 중간적외선 (400-4000 cm-1) 영역에서 열수기원 일라이트의 층간 결합상태와 화학조성간의 관계를 해석하였다. 중간 적외선 영역에서는 2M1 다형의 Al-O-Al 및 Al-O-Si 결합이 1Md 형의 것보다 강한 것으로 나타났다. 원적외선 영역에서는 세 종류의 K-O 결합이 111-114, 135-143 및 167-168 cm-1에서 인지되었다. 2M1과 1Md 다형간의 가장 큰 차이는 2M1형의 층간결합이 1Md형보다 상대적으로 강하여 K가 층간에 보다 강하게 결합되어 있다는 점이며, 두 다형의 층간결합의 상태는 서로 상이하다. K-Oinner band는 (OH) stretching band의 진동수가 높을수록 커지며, (OH) stretching band는 팔면체의 양이온 (Fe+Mg)의 함량에도 영향을 받는 것으로 나타났다.

• Journal of the Korean Chemical Society
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• v.39 no.7
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• pp.501-507
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• 1995

The electronic structure of cis-$[Cr(cyclam)Cl_2]Cl$ has been investigated by the emission and excitation spectroscopy at 77K, and infrared and visible spectroscopy at room temperature. The ten electronic transitions due to spin-allowed and spin-forbidden are assigned. The zero-phonon line in the excitation spectrum splits into two components by $139\;cm^{-1}$, and it can be reproduced by modern ligand field theory. According to the results of ligand field analysis, we can confirm that nitrogen atoms of the cyclam ligand have a strong ${\sigma}$-donor character, but chloride ligand has weak ${\sigma}-$ and ${\pi}-$donor properties toward chromium(III) ion.

• Journal of the Korean Chemical Society
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• v.50 no.3
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• pp.183-189
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• 2006

A series of substituted styryl 4-methoxy-1-naphthyl ketones [(2E)-1-(4-methoxy-1-naphthyl)-3-phenyl-2-propen-1-ones] were synthesized using facile method of microwave assisted condensation reaction. The yield of chalcones is more than 90%. They are characterized by their physical constants, micro analysis, infrared (KBr, 4000-400 cm？1) and NMR both 1H and 13C spectral data. From infrared spectra, the s-cis and s-trans stretching vibrations of carbonyl group, from NMR spectra the ethylenic proton and carbon chemical shifts (ppm) are assigned. These spectral data are correlated with various Hammett substituent constants. From the results of statistical analysis the effect of substituents on CO, ？ and ？ proton and carbons are explained.

• Clean Technology
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• v.20 no.2
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• pp.103-107
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• 2014

Acrylic acid is a commodity chemical which is applicable for various industries such as polymer and textile industry. Currently, it has been produced by chemical synthesis from petroleum. However, due to the high price of petroleum and global $CO_2$ emission, renewable materials such as sugar are interesting alternative carbon sources for the biological production of acrylic acid. For an economic production of acrylic acid from renewable carbon sources, a cost effective separation process for acrylic acid should be needed. In this study, reactive extraction by TOA (tri-n-octylamine) was used for the recovery of acrylic acid from its aqueous solutions. The effects of polarity of diluents and concentration of TOA on extraction equilibrium were investigated. The extraction efficiency was proportional to concentration of TOA and polarity of diluents and its value was more than 95% in the case of sufficient concentration of TOA. From IR spectroscopy, it was concluded that the ratio of (1,1) acid-amine complex was increased and the ratio of acid dimer was decreased with concentration of TOA. Equilibrium model based on IR spectroscopy was well fitted with experimental data.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.9
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• pp.2065-2070
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• 2010

The diluted PMMA treated $SiO_2$ films as an passivation materials for semiconductor devices was researched by using the FTIR spectra. The diluted PMMA solution with various ratios changed the surface of $SiO_2$ film as the hydrophilic, hydrophobic or hybrid type properties. The sample 7 with little carbon content showed dramatically the chemical variation by the FTIR spectra analysis. Beacuse the little carbon with electrons decreased the polarity and surface energy on the $SiO_2$ film, and then became a stable bonding structure and decreased the leakage current. The FTIR spectra can define the detail variation due to the chemical reaction on the organic thin film, and help to research the characteristic of the organic materials.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.97-100
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• 2002

PVDF를 전장하에서 용융결정화 하는 경우에 전장의 세기가 증가할수록 전기적으로 불활성인 $\alpha$-결정의 핵생성속도는 지연되는 반면에 전기적으로 활성을 갖는 ν-결정의 핵생성은 빨라지는 것으로 Stein 연구그룹이 일찍이 보고한 바 있다. [1,2] 그러나 실제로 PVDF를 용응 결정화하는 경우에는 결정화온도가 그다지 낮지 않는 경우에는 $\alpha$-결정과 ν-결정이 혼재되어 나타나기 때문에 외부 전장하리서의 용융결정화시에 외부전장의 세기가 $\alpha$-결정과 ν-결정의 핵생성속도 및 성장속도에 미치는 영향을 분리하여 해석한 논문은 거의 없다. (중략)