• Title/Summary/Keyword: second derivative spectra

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Determination of Acetaminophen in Tablet Formulations by Second Derivative Ultraviolet Spectrometry (2차 미분 자외부 분광광도법에 의한 정제중의 아세트아미노펜 정량)

  • 유경수;고익배
    • YAKHAK HOEJI
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    • v.30 no.2
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    • pp.100-103
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    • 1986
  • The second derivative absorption spectra of acetaminophen in commercial tablet forms were measured without prior separation from other pharmaceutical adjuvants. The second derivative spectra of acetaminophen were found to have no influence on the characteristic absorbance band of it. A plot of 25 sets of the ordinate (Z) values with various acetaminophen concentrations mixed in other additives gave a straight line (correlation coefficient, 0.9999) and the slope was 2.901${\times}10^{-2}Z$ value/($\mu\textrm{g}$/ml). The procedures were sufficiently sensitive, precise and economical for the assay of tablets of acetaminophen.

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A Study on the Chemical State in the ONO Superthin Film by Second Derivative Auger Spectra (2차 미분 Auger 스펙트럼을 이용한 ONO 초박막의 결합상태에 관한 연구)

  • 이상은;윤성필;김선주;서광열
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.11 no.10
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    • pp.778-783
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    • 1998
  • Film characteristics of thin ONO dielectric layers for MONOS(metal-oxide-nitride-oxide-semiconductor) EEPROM was investigated by TEM, AES and AFM. Seocnd derivative spectra of Auger Si LVV overlapping peak provide useful information fot chemical state analysis of superthin film. The ONO film with dimension of tunnel oxide 23$\AA$, nitride 33$\AA$, and blocking oxide 40$\AA$ was fabricated. During deposition of the LPCVD nitride film on tunnel oxide, this thin oxide was nitrized. When the blocking oxide was deposited on the nitride film, the oxygen not only oxidized the nitride surface, but diffused through the nitride. The results of ONO film analysis exhibits that it is made up of $SiO_2$ (blocking oxide)/O-rich SiON(interface)/N-rich SiON(nitride)/ O-rich SiON(tunnel oxide)

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Chemical Structure Analysis on the ONO Superthin Film by Second Derivative AES Spectra (2차 미분 AES 스펙트럼에 의한 ONO 초박막의 화학구조 분석)

  • 이상은;윤성필;김선주;서광열
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1998.06a
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    • pp.79-82
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    • 1998
  • Film characteristics of thin ONO dielectric layers for MONOS(metal-oxide-nitride-oxide-semiconductor) EEPRM was investigated by AES and AFM. Second derivative spectra of AES Si LVV overlapping peak provided useful information for chemical state analysis of superthin film. The ONO films with dimension of tunneling oxide 24${\AA}$, nitride 33${\AA}$, and blocking oxide 40${\AA}$ were fabricated. During deposition of the LPCVD nitride films on tunneling oxide, this thin oxide was nitrized. When the blocking oxide were deposited on the nitride film, the oxygen not only oxidized the nitride surface, but diffused through the nitride. The results of ONO film analysis exhibits that it is made up of SiO$_2$(blocking oxide)/O-rich SiON(interface/N-rich SiON(nitride)/-rich SiON(interface)/N-rich SiON(nitride)/O-rich SiON(tunneling oxide).

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Modern Pretreatment methods in NIR Spectroscopy

  • Yukiteru Katsumoto;Jian Hui Jiang R.;James Berry;Yukihiro Ozaki
    • Near Infrared Analysis
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    • v.2 no.1
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    • pp.29-36
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    • 2001
  • This review paper outlines modern pretreatment methods used in NIR spectroscopy. The pretreatment methods can be divided into four categories. One method in is noise reduction. Smoothing is a representative method for the noise reduction. Another is baseline correction. The second derivative and multiplicative scatter correction (MSC) are most frequently employed for baseline correction. The third is centering and normalization and the last is resolution enhancement. Difference spectra, mean centering and second derivative are used in NIR spectroscopy as resolution enhancement methods. In this paper advantages and drawbacks of pretreatment methods currently used in NIR spectroscopy are discussed with many examples of NIR spectra.

Effect of Acetylation on Conformation of Glycinin (아세틸화가 Glycinin의 구조에 미치는 영향)

  • Kim, Kang-Sung;Rhee, Joon-Shick
    • Korean Journal of Food Science and Technology
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    • v.21 no.5
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    • pp.714-720
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    • 1989
  • Effects of acetylation on conformational changes of glycinin was studied using solvent perturbation, second derivative spectroscopy, near uv circular dichroism spectra and viscosity. Glycinin with purity of more than 93% was used for the experiment. Modification was carried out with acetic anhydride and glycinin with lysine residue modification of 0%, 28%, 65%, 85%, and 95% were used for the experiment. The result of solvent perturbation using some selected perturbants, such as glycerol, ethylene glycol, and dimethyl sulfoxide revealed that acetylation has caused increase In solvent accessibility of tyrosine residues from less than 40% in native protein to more than 70% for 95% acetylated glycinin. This was confirmed by second derivative spectroscopy. Near ultraviolet circular dichroism revealed that the spectra of native and acetylated glycinin were almost identical differing only in intensity and no other useful information could be derived from it. However, in the case of 95% acetylated glycinin the influence of tryptophan on the spectrum was more pronounced Specific viscosity of glycinin also increased by modification, the extent of which depended upon the degree of acetylation. These results supported that acetylation had caused globular conformation of glycinin to be expanded and denatured.

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PRELIMINARY STUDY ON NIR SPECTRA OF RETROGRADED STARCH

  • Terazawa, Yoko;Maekawa, Takaaki;Kawano, Sumio
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1515-1515
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    • 2001
  • Retrogradation of starch is one of important quality indexes for food based on starch such as rice. Therefore, in this research, possibility of near infrared spectroscopy to determine the degree of the retrogradation was examined. The degree of the retrogradation was indicated as the degree of geratinization analyzed by BAP(-amylase-pullulanase) method. 20 samples which have a wide range of the degree of the retrogradation were prepared and the NIR spectra of the samples were measured in reflectance mode with the NIR Systems 6500. In the correlation plots calculated from the 2nd derivative values of the MSC treated spectra and the degree of the geratinization, the major negative peaks of 1544 nm and 2258 nm, and the major positive peaks of 1460 nm, 1602 nm, 1766 nm and 2136 nm could be observed, indicating that NIR absorption at the positive peak wavelengths became strong while the absorption at the negative peak wavelengths became weak as the degree of the retrogradation increased. Because there is negative correlation between the degree of the retrogradation and the degree of the geratinization. As a result of MLR using the 2nd derivative values of the MSC treated spectra and the degree of the geratinization, good calibration equation which include 2258 nm as the first wavelength and 1764 nm as the second one could be obtained, indicating that NIR spectroscopy has a possibility to detect the retrogradation of starch. In order to find the assignment of the bands observed in the correlation plots, further study may be needed.

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Comparison of Performance of Models to Predict Hardness of Tomato using Spectroscopic Data of Reflectance and Transmittance (토마토 반사광과 투과광 스펙트럼 분석에 의한 경도 예측 성능 비교)

  • Kim, Young-Tae;Suh, Sang-Ryong
    • Journal of Biosystems Engineering
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    • v.33 no.1
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    • pp.63-68
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    • 2008
  • This study was carried out to find a useful method to predict hardness of tomato using optical spectrum data. Optical spectrum of reflectance and transmittance data were collected processed by 9 kind of preprocessing methods-normalizations of mean, maximum and range, SNV (standard normal variate), MSC (multiplicative scatter correction), the first derivative and second derivative of Savitzky-Golay and Norris-Gap. With the preprocessed and non-processed original spectrum data, prediction models of hardness of tomato were developed using analytical tools of PLS (partial least squares) and MLR (multiple linear regression) and tested for their validation. The test of validation resulted that the analytical tools of PLS and MLR output similar performances while the transmittance spectra showed much better result than the reflectance spectra.

한국산 참기름의 진위성 판별을 위한 NIR 분석

  • Kim, Yeong-Su
    • Bulletin of Food Technology
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    • v.9 no.4
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    • pp.87-93
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    • 1996
  • NIR(근적외) 분광분석법이 참기름의 원산국 판별에 이용 가능 한지를 알아보기 위하여 32종의 시료에 대하여 NIR 분석을 실시한 후, 그 분광 데이터에 대하여 principal component analysis(주성분 분석)와 canonical variate analysis(정준판별분석)을 실시하였다. 10개의 주성분과 400-2500nm에서 second derivative log(1/R) 데이터를 이용할 경우, 제1 및 제2 정준판별함수는 3개 참기름 그룹(한국산 참깨로 제조한 13종의 참기름 그룹, 외국산 참깨로 제조한 10종의 국산 참기름 그룹 및 미지의 참깨로 제조한 9종의 참기름 그룹)을 판별하는데 가장 효과적이었다. 사용된 canonical variate analysis는 참기름 시료를 100%의 정확도로 그 지리적 출처를 분류하였다. 한편 second derivative log(1/R) spectra상의 파장범위 498-500, 668, 1698-1724, 2242-2256, 2302-2306, 2328 및 2348~2352nm에서 3개 그룹간에 현저한 차이가 발견되었다.

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POLYNOMIALLY DEMICOMPACT OPERATORS AND SPECTRAL THEORY FOR OPERATOR MATRICES INVOLVING DEMICOMPACTNESS CLASSES

  • Brahim, Fatma Ben;Jeribi, Aref;Krichen, Bilel
    • Bulletin of the Korean Mathematical Society
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    • v.55 no.5
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    • pp.1351-1370
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    • 2018
  • In the first part of this paper we show that, under some conditions, a polynomially demicompact operator can be demicompact. An example involving the Caputo fractional derivative of order ${\alpha}$ is provided. Furthermore, we give a refinement of the left and the right Weyl essential spectra of a closed linear operator involving the class of demicompact ones. In the second part of this work we provide some sufficient conditions on the inputs of a closable block operator matrix, with domain consisting of vectors which satisfy certain conditions, to ensure the demicompactness of its closure. Moreover, we apply the obtained results to determine the essential spectra of this operator.

Fundamental Investigation of Non-invasive Determination of Alcohol in Blood by Near Infrared Spectrophotometry (근적외선 분광분석법을 이용한 음주측정기술 개발에 관한 연구)

  • Chang, Soo-Hyun;Cho, Chang-Hee;Woo, Young-Ah;Kim, Hyo-Jin;Kim, Young-Man;Lee, Kang-Boong;Kim, Young-Woon;Park, Sung-Woo
    • Analytical Science and Technology
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    • v.12 no.5
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    • pp.375-381
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    • 1999
  • Near infrared spectrophotometry(NIR) was developed as a non-invasive determination of blood alcohol. The first pure alcohol/water samples were prepared with ethanol concentration from 0.01 to 0.1%(w/w). Analysis of the second-derivative data was accomplished with multilinear regression(MLR). The standard error of calibration(SEC) of ethanol in ethanol/water solutions was approximately 0.0039%. The calibration models were established from the blood alcohol spectra by MLR and PLSR analysis. The best calibration was built with the second-derivative spectra of 2266 and 2326 nm by MLR. Second-derivative spectra in the spectral ranges of 1100~1340, 1500~1796 and 2064~2300 nm with four PLSR factors provided the standard error of prediction(SEP) of 0.030%(w/w). These results indicate that NIR may be applied for a fast non-invasive determination of alcohol in the blood.

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