• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2008.11a
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• pp.114-114
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• 2008

자동차 보수도료 경화는 주로 열풍방식을 사용하고 있지만 적외선 가열방식을 사용하면 품질이 향상 되고 에너지 절약 등의 이점이 있다. 따라서 자동차 보수도료의 경화용으로 사용할 적외선 방사체를 개발하였다. 자동차 보수도료의 적외선 흡수 스펙트럼과 적외선 방사체 방사 스펙트럼이 일치해야 도료의 경화효율이 우수해짐을 알 수 있었고 열풍방식과 비교하여 경화된 도막의 품질 및 경화시간에 대한 실험데이터를 분석하였다.

• 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 Institute of Fire Science and Engineering Conference
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• 2010.04a
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• pp.360-365
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• 2010

현장에서 내화피복재(내화뿜칠재)의 품질을 확인할 수 있는 간편한 품질방법이 부재하여 열 중량-적외선 분석 장치를 이용하여 내화피복재의 일치성 분석을 시도하였다. 국내의 9종 인정 내화뿜칠재에 대한 열 분해 곡선을 확인 하고, 이때 특정 성분을 측정하였다. 국내 시판 9종의 내화뿜칠재는 $400^{\circ}C$이내에서 무게변화가 15% 정도 감소하다가 $400^{\circ}C$부터 $1200^{\circ}C$까지 무게 변화가 거의 없이 유지되는 특성을 보였다. 이때 초기 열분석으로부터 발생되는 가스에 대한 적외선 스펙트럼의 분석결과로 O-H band 및 $CO_2$가 확인되었다. 하지만 내화성능이 없는 흡음뿜칠재의 경우에는 $400^{\circ}C$부터 $1200^{\circ}C$사이에 무게 중량이 급격하게 변화되는 것을 확인 할 수 있었다. 열중량-적외선 분석 장치를 이용하여 두 재료의 열분해곡선 및 적외선스펙트럼 변화를 측정하였으며, 이 분해 곡선을 통계처리 방식인 PCA (Principal components analysis)통계처리를 통해서 내화뿜칠재의 진위 구분이 가능함을 확인하였다.

• Korean Journal of Mineralogy and Petrology
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• v.36 no.4
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• pp.259-271
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• 2023

Since the short-wave infrared spectrum has a significant range of variation depending on the production environment, countries with advanced resource exploration are collecting the spectrum and building a database. Representative organizations include the USGS and CSIRO, and they are currently carrying out a project in China that can synthesize and use a large number of existing data. The USGS library provides a total of 2,457 spectra targeting not only minerals but also various materials that respond to infrared radiation. Among these, there are 1,276 mineral spectra, which are about half of the total. The spectrum title includes information, such as analysis devices (NIC4, BECK, ASDNG, etc.), purity codes (a, b, c, d, u), and measurement methods (AREF, RREF, RTGC, TRAN). Analyzed raw data are provided in ASCII and GIF format. The CSIRO library has a total of 502 spectra, of which the majority, 493, correspond to mineral spectra. The USGS library is a free, publically available resource, while the CSIRO library is bundled with TSG8 or must be purchased separately. Among these, when comparing the eight spectra whose spectral shapes can be analyzed with the spectra of domestic illite, the positions of the absorption peaks are significantly different from those of domestic illite, except for one Japanese illite. Additional research will be needed to determine the causes of such differences, and the domestically relevant databases should be established as well.

• Journal of the Korean Society for Nondestructive Testing
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• v.32 no.1
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• pp.7-11
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• 2012

For fault detection about the abrasion stage of rotational machineries under the dynamic loading conditions unlike the traditional diagnosis method used in the past decade, the infrared thermographic method with its distinctive advantages in non-contact, non-destructive, and visible aspects is proposed. In this paper, by applying a rotating deep-grooved ball bearing, passive thermographic experiments were conducted as an alternative way to proceeding the traditional fault monitoring on spectrum analyzer. As results, the thermographic experiment was compared with the traditional vibration spectrum analysis to evaluate the efficiency of the proposed method. Based on the results obtained as NDT, the temperature characteristics and abnormal fault detections of the ball bearing according to the abrasion stage were analyzed.

• Analytical Science and Technology
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• v.5 no.3
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• pp.285-294
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• 1992

Structures of dimers of the acetonitrile and DMF diluted by carbon-tetrachloride and xenon matrices at 80K were studied with infrared absorption spectroscopy. Sample and matrix materials were codeposited onto a KBr cold trapping window. Infrared absorption spectra of pure samples and diluted samples were compared to explain the structures of dimers. The acetonitrile dimer showed the antiparallel shape and the DMF dimer showed the linear shape. After annealing, the infrared spectrum of the diluted sample showed the same shape with that of the pure sample.

• Journal of the Mineralogical Society of Korea
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• v.6 no.2
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• pp.105-115
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• 1993

$M{\ddot{o}}ssbauer$ and Infrared absorption spectra of the iron-bearing tourmaline minerals show that the ferrous and ferric ions occupy the Y and Z octahedral sites. The Fe ions are almost ferrous, predominantly partitioning into Y site and partly take in Z site. The $Fe^{2+}$ content of the Z sites in brownish black tourmaline minerals are higher than that in blue/green tourmaline minerals. Therefore, 720 nm peak of brownish black samples is broader than that of blue/green samples in optical spectra. All of the blue/green tourmaline minerals used in experiment have only $Fe^{2+}$ ion. The IR spectra of tourmaline depend on the cation environments around OH groups, as also evidenced by their chemical analyses. There appear no difference in IR spectrum between O(1)H and O(3)H binding characters in the heat-treated samples. But the characteristic $3565cm^{-1}$ peak appears in the ferrous hydroxyl bearing silicates, where dehydroxylation temperature for OH coordinated to $Fe^{2+}$ is $700{\sim}800^{\circ}C$.

• Journal of the Korean Ceramic Society
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• v.22 no.2
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• pp.58-62
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• 1985

2.5~40$mu extrm{m}$ 영역에서 $As_2S_3$ 및 $GeS_{2.1}$ 유리의 적외선흡수에 관하여 연구했다. Lucovsky와 그의 연구팀이 제창훈 분자 모델에 의하면 8-20$\mu\textrm{m}$ 영역에서 위의 유리물질의 multiphonon 흡수대는 고립된 각 분자의 기본진동대의 overtone 및 combination과 같다. Lucovsky와 Galeener는 이이론에 입각하여 network 구조를 갖는 유리가 적외선 및 라만 스펙트럼에서 나타나는 multiphonon combination 과 overtone 진동수를 예언하는 실험적 선택룰을 제안했다 우리가 얻은 As2S3 및 GeS2.1 유리의 적외선 스펙트럼은 이 유리에 대해 적용한 위의 실험법칙과 잘 일치한다.

• Journal of the Korean Chemical Society
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• v.50 no.1
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• pp.7-13
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• 2006

infrared(IR) absorption spectra were calculated for the ethyl ester of p-tert-butylcalix[4]arene (1) in the cone conformer and its alkali-metal-ion complex. The vibrational spectra were obtained by restricted Hartree-Fock (RHF) calculations with the 6-31G basis set. The characteristic vibrational frequencies of various C-O and C=O stretching motions of the complexes show that the structure of 1+K+ complex is almost of C4v symmetry compared to 1+Na+ (C2v) analogue. The theoretical results for the host molecule 1 and complex (1+Na+) were compared with the experimental results, and the calculated vibrational frequencies agree well with the features of the experimental spectra.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.7
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• pp.626-634
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• 2015

In the present study, numerical predictions of infrared spectra for $CO_2$ molecule were conducted. Absorption coefficients of $CO_2$ which are required for simulating the spectra, were calculated by using a line-by-line method and by adopting spectroscopic parameters from the radiation databases, HITEMP2010 and CDSD-4000. Simulations were made in the 2.7, 4.3, and $15{\mu}m$ band regions, and the results were compared with the measurements of other researchers. It was found that the calculated results are well matched with the various measurements. However, in the $4.3{\mu}m$ band region, the CDSD-4000 based calculation yields a better fit to the measurement than the HITEMP2010 based calculation does.