• 제목/요약/키워드: techniques: spectroscopic

검색결과 260건 처리시간 0.03초

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.

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.

극초단 펄스레이저의 분광학 응용 (Spectroscopic Applications of Ultrashort Pulse Lasers)

  • 김동호
    • 한국광학회지
    • /
    • 제1권1호
    • /
    • pp.87-97
    • /
    • 1990
  • With the recent advent of various ultrashort pulse lasers, time-resolved laser spectroscopic techniques have been widely recognized as versatile tools to study ultrafast phenomena in many research areas. These techniques are currently being employed not only to study atomic and molecular physics but to characterize the excited state or the carrier dynamics on surfaces of semiconductors, metals and thin layer materials. Also the sweetching speed measurement of ultrafast electro-optic devices using ultrashort laser pulses becomes important in high-speed electronics. Here, some principles of spectroscopic techniques with ps or fs lasers and their applications are summarized briefly.

  • PDF

탄소의 원료로 일산화탄소를 사용한 다이아몬드 박막 성장 관찰에 대한 분광 Ellipsometry의 응용 (The Spectroscopic Ellipsometry Application to the Diamond Thin Film Growth Using Carbon Monoxide(CO) as a Carbon Source)

  • 홍병유
    • 한국전기전자재료학회논문지
    • /
    • 제11권5호
    • /
    • pp.371-377
    • /
    • 1998
  • The plasma chemical vapor deposition is one of the most utilized techniques for the diamond growth. As the applications of diamond thin films prepared by plasma chemical vapor deposition(CVD) techniques become more demanding, improved fine-tuning and control of the process are required. The important parameters in diamond film deposition include the substrate temperature, $CO/H_2$gas flow ratio, total gas pressure, and gas excitation power. With the spectroscopic ellipsometry, the substrate temperature as well as the various parameters of the film can be determined without the physical contact and the destructiveness under the extreme environment associated with the diamond film deposition. Through this paper, the important parameters during the diamond film growth using $CO+H_2$are determined and it is shown that $sp^2$ C in the diamond film is greatly reduced.

  • PDF

단일벽 탄소나노튜브의 분산도 정량적 평가 (The Quantitative Characterization of the Dispersion State of Single-Walled Carbon Nanotubes)

  • 윤도경;최재붕;김영진;백승현
    • 대한기계학회논문집A
    • /
    • 제31권4호
    • /
    • pp.483-489
    • /
    • 2007
  • We have investigated quantitative measurement techniques of the degree of dispersion of single-walled carbon nanotubes (SWNTs). SWNTs were suspended in aqueous media using a sodium dodecyl sulfate (SDS) surfactant. SWNTs with different dispersion states were prepared by controlling the intensity and time of sonication and centrifugation. The laser spectroscopic techniques were employed to characterize the dispersion state; i.e., raman fluorescence and absorption spectroscopic techniques. Raman spectroscopy has been used to probe the dispersion and aggregation state of SWNTs in solution. Individually suspended SWNTs show increased fluorescence peaks and decreased roping peaks at a raman shift 267 $cm^{-1}$ compared with the samples containing bundles of SWNTs. The ultraviolet-visible-near infrared (UV-vis-NIR) absorption spectrum of decanted supernatant samples show sharp van Hove singularity peaks

화학분석 기반 폭발물 탐지 기술 동향 (Research Trends in Chemical Analysis Based Explosive Detection Techniques)

  • 문상현;이원주;이기영
    • 공업화학
    • /
    • 제33권1호
    • /
    • pp.1-10
    • /
    • 2022
  • 본 논문은 주요 폭발물 탐지 기술에 대한 원리, 장단점 및 향후 필요한 연구 분야에 대한 총설이다. 폭발물 탐지 기술은 분광학적 방법(spectroscopic methods), 감지기 기술(sensor techniques), 후각 감지기(olfactory type sensors)로 분류할 수 있다. 이러한 탐지 기술은 많은 발전이 있었지만 폭발물 탐지를 위한 판별성, 휴대성, 감도에 관한 연구 가능성이 높은 것으로 보인다.

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.

Review of Rice Quality under Various Growth and Storage Conditions and its Evaluation using Spectroscopic Technology

  • Joshi, Ritu;Mo, Changyeun;Lee, Wang-Hee;Lee, Seung Hyun;Cho, Byoung-Kwan
    • Journal of Biosystems Engineering
    • /
    • 제40권2호
    • /
    • pp.124-136
    • /
    • 2015
  • Purpose: Grain quality is a general concept that covers many characteristics, ranging from physical to biochemical and physiochemical properties. Rice aging during storage is currently a challenge in the rice industry, and is a complicated process involving changes in all of the above properties. Spectroscopic techniques can be used to obtain information on the quality of rice samples in a non-destructive manner. Methods: The objective of this review was to highlight the factors that contribute to rice quality and aging, and to describe various spectroscopic modalities, particularly vibrational and hyperspectral imaging, for the assessment of rice quality. Results: Starch and protein are the main components of the rice endosperm, and are therefore key factors contributing to eating and cooking quality. While the overall starch, protein, and lipid content in the rice grain remains essentially unchanged during storage, structural changes do occur. These changes affect pasting and gel properties, and ultimately the flavor of cooked rice. In addition, grain quality is significantly affected by growing and environmental conditions, such as water availability, temperature, fertilizer application, and salinity stress. These properties can be evaluated using spectroscopic techniques, and rice samples can be discriminated by using multivariate statistical analysis methods. Conclusion: Hyperspectral imaging and vibrational spectroscopy techniques have good potential for determining rice quality properties in a non-invasive manner, i.e., not requiring the introduction of instruments into the rice grain.

진동분광실험을 이용한 n-Paraffin혼합물의 결정화에 관한 연구 (Vibrational Spectroscopic Studies of Crystallization in Mixed n-Paraffins)

  • 김도균;임현주;최선남;김성수;송기국
    • 폴리머
    • /
    • 제26권6호
    • /
    • pp.752-758
    • /
    • 2002
  • 사슬길이가 서로 다른 두 종류의 n-paraffin 혼합물이 결정을 형성할 때 사슬의 움직임과 형성된 라멜라의 구조를 조사하기 위하여 FTIR, FT-Raman, XRD 실험방법을 이용하였다. FTIR crystal field splitting, Raman longitudinal acoustic mode, 그리고 SAXS long period 측정 결과들을 비교하여 사슬길이가 다른 두 n-paraffin 사슬이 혼합되어 하나의 라멜라를 형성하거나 분리되어 각각의 라멜라를 형성하는 과정을 연구하였다.