• 제목/요약/키워드: spectroscopy techniques

검색결과 594건 처리시간 0.023초

단열 코팅재료의 비파괴 평가기법 (Non-Destructive Evaluation for Material of Thermal Barrier Coatings)

  • 이철구;김태형
    • 한국공작기계학회논문집
    • /
    • 제14권1호
    • /
    • pp.44-51
    • /
    • 2005
  • Material degradation is a multibillion-dollar problem which affects all the industries amongst others. The last decades have seen the development of newer and more effective techniques such as Focused-ion beam(FIB), Transmission electron microscopy(TEM), Secondary-ion mass spectroscopy(SIMS), auger electron spectroscopy(AES), X-ray Photoelectron spectroscopy(XPS) , Electrochemical impedance spectroscopy(EIS), Photo- stimulated luminescence spectroscopy(PSLS), etc. to study various forms of material degradation. These techniques are now used routinely to obtain information on the chemical state, depth profiling, composition, stress state, etc. to understand the degradation behavior. This paper describes the use of these techniques specifically applied to materials degradation and failure analysis.

Spectroscopic Techniques for Nondestructive Quality Inspection of Pharmaceutical Products: A Review

  • Kandpal, Lalit Mohan;Park, Eunsoo;Tewari, Jagdish;Cho, Byoung-Kwan
    • Journal of Biosystems Engineering
    • /
    • 제40권4호
    • /
    • pp.394-408
    • /
    • 2015
  • Spectroscopy is an emerging technology for the quality assessment of pharmaceutical samples, from tablet manufacturing to final quality assurance. The traditional methods for the quality management of pharmaceutical tablets are time consuming and destructive, while spectroscopic techniques allow rapid analysis in a non-destructive manner. The advantage of spectroscopy is that it collects both spatial and spectral information (called hyperspectral imaging), which is useful for the chemical imaging of pharmaceutical samples. These chemical images provide both qualitative and quantitative information on tablet samples. In the pharmaceutics, spectroscopic techniques are used for a variety of applications, such as analysis of the homogeneity of powder samples as well as determination of particle size, product composition, and the concentration, uniformity, and distribution of the active pharmaceutical ingredient in solid tablets. This review paper presents an introduction to the applications of various spectroscopic techniques such as hyperspectroscopy and vibrational spectroscopies (Raman spectroscopy, FT-NIR, and IR spectroscopy) for the quality and safety assessment of pharmaceutical solid dosage forms. In addition, various chemometric techniques that are highly essential for analyzing the spectroscopic data of pharmaceutical samples are also reviewed.

Raman Chemical Imaging Technology for Food and Agricultural Applications

  • Qin, Jianwei;Kim, Moon S.;Chao, Kuanglin;Cho, Byoung-Kwan
    • Journal of Biosystems Engineering
    • /
    • 제42권3호
    • /
    • pp.170-189
    • /
    • 2017
  • Purpose: This paper presents Raman chemical imaging technology for inspecting food and agricultural products. Methods The paper puts emphasis on introducing and demonstrating Raman imaging techniques for practical uses in food analysis. Results & Conclusions: The main topics include Raman scattering principles, Raman spectroscopy measurement techniques (e.g., backscattering Raman spectroscopy, transmission Raman spectroscopy, and spatially offset Raman spectroscopy), Raman image acquisition methods (i.e., point-scan, line-scan, and area-scan methods), Raman imaging instruments (e.g., excitation sources, wavelength separation devices, detectors, imaging systems, and calibration methods), and Raman image processing and analysis techniques (e.g., fluorescence correction, mixture analysis, target identification, spatial mapping, and quantitative analysis). Raman chemical imaging applications for food safety and quality evaluation are also reviewed.

Synthesis and spectroscopic characterization of zinc ferrite nanoparticles

  • Arora, Shefali;Nandy, Subhajit;Latwal, Mamta;Pandey, Ganesh;Singh, Jitendra P.;Chae, Keun H.
    • Advances in nano research
    • /
    • 제13권5호
    • /
    • pp.437-451
    • /
    • 2022
  • Synthesis approaches usually affect the physical and chemical properties of ferrites. This helps ferrite materials to design them for desired applications. Some of these methods are mechanical milling, ultrasonic method, micro-emulsion, co-precipitation, thermal decomposition, hydrothermal, microwave-assisted, sol-gel, etc. These methods are extensively reviewed by taking example of ZnFe2O4. These methods also affect the microstructure and local structure of ferrite which ultimately affect the physical and chemical properties of ferrites. Various spectroscopic techniques such as Raman spectroscopy, Fourier Transform Infrared spectroscopy, Ultra Violet-Visible spectroscopy, Mossbauer spectroscopy, extended x-ray absorption fine structure, and electron paramagnetic resonance are found helpful to reveal this information. Hence, the basic principle and the usefulness of these techniques to find out appropriate information in ZnFe2O4 nanoparticles is elaborated in this review.

The Application of NMR Techniques to the Structural Confirmation of O-Substituted 3,4-Dihydroxyphenylacetic Acid Derivatives

  • Lee, Sueg-Geun;Choi, Joong-Kwon;Park, No-Sang;Hong, Mi-Sook;Ha, Deok-Chan
    • Bulletin of the Korean Chemical Society
    • /
    • 제13권1호
    • /
    • pp.87-91
    • /
    • 1992
  • The structures of the compounds, 1, 2, 3, and 4, which were precursors of analgesics, were confirmed by modern NMR techniques. The complete $^{13}C-NMR$ assignments of these systems were established by applying COLOC (COrrelated spectroscopy for LOng range Couplings), HETCOR (HETeronuclear CORrelated spectroscopy), RCT (Relay Coherence Transfer), and NOE difference spectroscopy. The limitation of COLOC approach which has been widely used recently is discussed.

SPATIO-SPECTRAL MAXIMUM ENTROPY METHOD: II. SOLAR MICROWAVE IMAGING SPECTROSCOPY

  • Bong, Su-Chan;Lee, Jeong-Woo;Gary Dale E.;Yun Hong-Sik;Chae Jong-Chul
    • 천문학회지
    • /
    • 제38권4호
    • /
    • pp.445-462
    • /
    • 2005
  • In a companion paper, we have presented so-called Spatio-Spectral Maximum Entropy Method (SSMEM) particularly designed for Fourier-Transform imaging over a wide spectral range. The SSMEM allows simultaneous acquisition of both spectral and spatial information and we consider it most suitable for imaging spectroscopy of solar microwave emission. In this paper, we run the SSMEM for a realistic model of solar microwave radiation and a model array resembling the Owens Valley Solar Array in order to identify and resolve possible issues in the application of the SSMEM to solar microwave imaging spectroscopy. We mainly concern ourselves with issues as to how the frequency dependent noise in the data and frequency-dependent variations of source size and background flux will affect the result of imaging spectroscopy under the SSMEM. We also test the capability of the SSMEM against other conventional techniques, CLEAN and MEM.

Spectroscopic Techniques for Nondestructive Detection of Fungi and Mycotoxins in Agricultural Materials: A Review

  • Min, Hyunjung;Cho, Byoung-Kwan
    • Journal of Biosystems Engineering
    • /
    • 제40권1호
    • /
    • pp.67-77
    • /
    • 2015
  • Purpose: Fungal secondary metabolite (mycotoxin) contamination in foods can pose a serious threat to humans and animals. Spectroscopic techniques have proven to be potential alternative tools for early detection of mycotoxins. Thus, the aim of this review is to provide an overview of the current developments in nondestructive food safety testing techniques, particularly regarding fungal contamination testing in grains, focusing on the application of spectroscopic techniques to this problem. Methods: This review focuses on the use of spectroscopic techniques for the detection of fungi and mycotoxins in agricultural products as reported in the literature. It provides an overview of the characteristics of the main spectroscopic methods and reviews their applications in grain analysis. Results: It was found that spectroscopy has advantages over conventional methods used for fungal contamination detection, particularly when combined with chemometrics. These advantages include the rapidness and nondestructive nature of this approach. Conclusions: While spectroscopy offers many benefits for the detection of mycotoxins in agricultural products, a number of limitations exist, which must be overcome prior to widespread adoption of these techniques.

Velocity measurements in complex flows of non-Newtonian fluids

  • Muller, Susan J.
    • Korea-Australia Rheology Journal
    • /
    • 제14권3호
    • /
    • pp.93-105
    • /
    • 2002
  • Experimental methods for making quantitative measurements of velocity fields in non-Newtonian fluids are reviewed. Techniques based on light scattering spectroscopy - laser Doppler velocimetry and homodyne light scattering spectroscopy, techniques based on imaging the displacement of markers - including particle image velocimetry and molecular tagging velocimetry, and techniques based on nuclear magnetic resonance imaging are discussed. The special advantages and disadvantages of each method are summarized, and their applications to non-Newtonian flows are briefly reviewed. Example data from each technique are also included.

무채혈 혈당 측정기의 혈당 측정 원리: 혈당 검출방법 중심으로 (Blood Glucose Measurement Principles of Non-invasive Blood Glucose Meter: Focused on the Detection Methods of Blood Glucose)

  • 안원식;김진태
    • 대한의용생체공학회:의공학회지
    • /
    • 제33권3호
    • /
    • pp.114-127
    • /
    • 2012
  • Recent technical advancement allows noninvasive measurement of blood glucose. In this literature, we reviewed various noninvasive techniques for measuring glucose concentration. Optical or electrical methods have been investigated. Optical techniques include near-infrared spectroscopy, Raman spectroscopy, optical coherence technique, polarization, fluorescence, occlusion spectroscopy, and photoacoustic spectroscopy. Electrical methods include reverse iontophoresis, impedance spectroscopy, and electromagnetic sensing. Ultrasound, detection from breath, or fluid harvesting technique can be used to measure blood glucose level. Combination of various methods is also promising. Although there are many interesting and promising technologies and devices, there need further researches until a commercially available non-invasive glucometer is popular.

VIBRATIONAL SPECTROSCOPY IN INDUSTRIAL CHEMICAL QUALITY CONTROL

  • Siesler, H.W.
    • 한국근적외분광분석학회:학술대회논문집
    • /
    • 한국근적외분광분석학회 2001년도 NIR-2001
    • /
    • pp.1081-1081
    • /
    • 2001
  • The constant need for quality improvement and production rationalization in the chemical and related industries has led to the increasing replacement of conservative control procedures by more specific and environmentally compatible analytical techniques. In this respect, vibrational spectroscopy has developed over the last yews - in combination with new instrumental accessories and statistical evaluation procedures - to one of the most important analytical tools for industrial chemical quality control and process monitoring in a wide field of applications. In the present communication this potential is demonstrated in order to further support the implementation of mid-infrared (MIR), near-infrared (NIR) and Raman spectroscopy Primarily as industrial on-line tools. To this end the data of selected feasibility studies will be discussed in terms of the individual strengths of the different techniques for the respective application.

  • PDF