• 제목/요약/키워드: functional near infrared spectroscopy

검색결과 39건 처리시간 0.026초

In-situ rf treatment of multiwall carbon nanotube with various post techniques for enhanced field emission

  • Ahn, Kyoung-Soo;Kim, Jun-Sik;Kim, Ji-Hoon;Kim, Chae-Ok;Hong, Jin-Pyo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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    • pp.859-862
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    • 2003
  • Well-aligned multiwall carbon nanotubes (MWCNTs) were prepared at low temperature of 400 $^{\circ}C$ by utilizing a radio frequency plasma-enhanced chemical vapor deposition (rf-PECVD) system. The MWCNTs were treated by an external rf plasma source and an ultra-violet laser in order to modify structural defect of carbon nanotube and to ablate possible contamination on carbon nanotube surface. Structural properties of carbon nanotubes were investigated by using a scanning electron microscopy (SEM), Raman spectroscopy, Fourier transformer Infrared spectroscopy (FTIR) and transmission electron microscope (TEM). In addition, the emission properties of the MWNTs were measured for the application of field emission display (FED) in near future. Various post treatments were found to improve the field emission property of carbon nanotubes.

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음향광학 파장선택 필터 기반 파장훑음 레이저를 이용한 시간-인코딩 된 근적외선 흡광도 측정 비교 연구 (Time-encoded Near-infrared (NIR) Spectroscopic Comparison of Absorbance Measurement Using an Acousto-optic NIR Swept Laser Source)

  • 장한솔;김경훈;한가희;조재두;김창석
    • 한국광학회지
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    • 제28권1호
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    • pp.22-27
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    • 2017
  • 본 논문에서는 음향광학 파장선택 필터(acousto-optic tunable filter) 기반의 파장훑음 레이저(wavelength swept laser)를 이용한 시간-인코딩 근적외선 분광 기술(time-encoded near-infrared spectroscopy)을 제안하였다. 파장훑음 레이저는 800 nm 근처 영역에서 이득 스펙트럼을 가지는 반도체 광 증폭기(semiconductor optical amplifier)를 기반으로 제작되었으며, 음향광학 파장선택 필터를 공진기 내부에 삽입함으로써 음향광학 파장선택 필터에 인가되는 전기적 라디오주파수에 따라 출력 파장을 선택할 수 있도록 하였다. 본 연구에서는 종래의 기술인 백색광 분광기 기반의 검출부 분광 근적외선 분광 기술과 제안된 파장훑음 레이저 기반의 광원부 분광 근적외선 분광 기술을 각각 이용하여 근적외선 흡수 염료 샘플의 흡광도를 각기 측정하여 실험적으로 비교함으로써 본 연구에서 제안하는 음향광학 파장선택 필터 기반 파장훑음 레이저를 이용한 근적외선 분광 기술의 특성을 증명하였다.

NIR - a Tool for Evaluation of Milling Procedure

  • Gergely, Sziveszter;Handzel, Lidia;Zoltan, Andrea;Salgo, Andras
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1125-1125
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    • 2001
  • Micro-scale test methods are producing small-sample size where the conventional physical and chemical tests can not be used (high standard deviation, uncertain sampling conditions, low repeatability). Different small-scale test methods were developed recently for determination of physico-chemical, functional, rheological properties of wheat or wheat dough using miniaturized instruments with sophisticated sample preparation/handling and mechanics (RVA, 2 g mixograph, micro-Z-arm mixer, small-scale noodle maker, micro-baking method etc.). The small-scale methodologies can be used as basic research tools or as technology supported measurements and can be also essential in the early selection for quality traits in breeding programs. The milling as a sample preparation step is essential procedure providing good quality flour or semolina samples from small amount of grain (5-10 g) in a reproducible and reliable way. The aim of present study was to use NIR as quality control tool, and to evaluate the recently developed and manufactured micro-scale lab mill (FQC-2000) produced by Inter-Labor Co. Ltd., Hungary. The milling characteristics of the new instrument were compared to other laboratory mills and the effects of milling action on the chemical composition of fractions were analysed. The fractions were tested with both chemical and near infrared spectroscopic methods. The micro-scale milling resulted significantly different yields, particle size distributions and different fractions from compositional point of view. The near infrared spectra were sensitive enough to distinguish the fractions obtained by different milling procedures. Quantitative NIR calibration equations were developed and tested in order to measure the chemical composition of characteristic milling fractions. Special qualification procedure the PQS (Polar Qualification System) method was used for detecting the differences between fractions obtained by macro and micro-milling procedures. The results and the limitations of PQS method in this application will be discussed.

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Evaluation of Millet (Panicum miliaceum subsp. miliaceum) Germplasm For Seed Fatty Acids Using Near-Infrared Reflectance Spectroscopy

  • Lee, Young-Yi;Kim, Jung-Bong;Lee, Ho-Sun;Jeon, Young-A;Lee, Sok-Young;Kim, Chung-Kon
    • 한국작물학회지
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    • 제57권1호
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    • pp.29-34
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    • 2012
  • The objective of this study was to rapidly evaluate fatty acids in a collection of millet (Panicum miliaceum subsp. miliaceum) of different origins so that this information could be disseminated to breeders to advance germplasm use and breeding. To develop the calibration equations for rapid and nondestructive evaluation of fatty acid content, near-infrared reflectance spectroscopy (NIRs) spectra (1104-2494 nm) of samples ground into flour ($n$=100) were obtained using a dispersive spectrometer. A modified partial least-squares model was developed to predict each component. For foxtail millet germplasm, our models returned coefficients of determination ($R^2$) of 0.89, 0.89, 0.89, and 0.92 for palmitic acid, oleic acid, linoleic acid, and total fatty acids, respectively. The prediction of the external validation set (n=10) showed significant correlation between references values and NIRs values ($r^2$=0.64, 0.90, 0.79, and 0.89 for palmitic acid, oleic acid, linoleic acid, and total fatty acids, respectively). Standard deviation/standard errors of cross-validation (SD/SECV) values were close to 3 (2.62, 2.40, 1.85, and 2.23 for palmitic acid, oleic acid, linoleic acid, and total fatty acids, respectively). These results indicate that these NIRs equations are functional for the mass screening and rapid quantification of the oleic and total fatty acids characterizing millet germplasm. Among the samples, IT153514 showed an especially high content of fatty acids ($48.14mg\;g^{-1}$), whereas IT123909 had a very low content ($34.44mg\;g^{-1}$).

Application of Near-Infrared Reflectance Spectroscopy to Rapid Determination of Seed Fatty Acids in Foxtail Millet (Setaria italica (L.) P. Beauv) Germplasm

  • Lee, Young Yi;Kim, Jung Bong;Lee, Sok Young;Lee, Ho Sun;Gwag, Jae Gyun;Kim, Chung Kon;Lee, Yong Beom
    • 한국육종학회지
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    • 제42권5호
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    • pp.448-454
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    • 2010
  • The objective of this study was to rapidly evaluate fatty acids in a collection of foxtail millet (Setaria italica (L.) P. Beauv) of different origins so that this information could be disseminated to breeders to advance germplasm use and breeding. To develop the calibration equations for rapid and nondestructive evaluation of fatty acid content, near-infrared reflectance spectroscopy (NIRs) spectra (1104-2494 nm) of samples ground into flour (n=100) were obtained using a dispersive spectrometer. A modified partial least-squares model was developed to predict each component. For foxtail millet germplasm, our models returned coefficients of determination ($R^2$) of 0.91, 0.89, 0.98 and 0.98 for strearic acid, oleic acid, linoleic acid, and total fatty acids, respectively. The prediction of the external validation set (n=10) showed significant correlation between references values and NIRs values ($r^2=0.97$, 0.91, 0.99 for oleic, linoleic, and total fatty acids, respectively). Standard deviation/standard error of cross-validation (SD/SECV) values were greater than 3 (3.11, 5.45, and 7.50 for oleic, linoleic, and total fatty acids, respectively). These results indicate that these NIRs equations are functional for the mass screening and rapid quantification of the oleic, linolenic, and total fatty acids characterizing foxtail millet germplasm. Among the samples, IT153491 showed an especially high content of fatty acids ($84.06mg\;g^{-1}$), whereas IT188096 had a very low content ($29.92mg\;g^{-1}$).

NIR Colorant용 Quaterrylene Bisimide의 합성 및 특성 연구 (Synthesis and Characterization of Quaterrylene Bisimide as NIR Colorant)

  • 박근수;정연태
    • 한국전기전자재료학회논문지
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    • 제24권5호
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    • pp.398-403
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    • 2011
  • Recently, Near-infrared (NIR)colorant is intriguing and attractive but full of challenges. Although some cyanine colorant have been commercialized, near-infrared colorant with intensive NIR absorption, good chemical and photo-stability, and high solubility still remain as target compound. Certain polycyclic aromatic compounds such as quaterrylene represent a key class of NIR colorant and also give rise to outstanding physical and chemical properties after appropriate chemical modification. In this study, We have tried to introduceimide functional group to quaterrylene in order to give chemical and thermal stability. Finally, N,N'-bis (2,6-diisopropylphenyl)-quarterrylene-3,4:13,14-tetracarboximide was synthesized and evaluated its properties using $^1H$ NMR, Maldi-tof, TGA, and UV/VIS/NIR spectroscopy as NIR colorant. The quaterrylene bisimide compound exhibit a excellent thermal stability and chemical stability.

기능적 근적외선 분광법(fNIRS)을 이용한 우세손에 따른 뇌 활성화도에 대한 융합 연구 (Convergence Study of Brain Activity by Dominant Hand Using functional near-infrared spectroscopy(fNIRS))

  • 김미경;박선하;박혜연
    • 한국융합학회논문지
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    • 제12권12호
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    • pp.323-330
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    • 2021
  • 본 연구에서는 10명의 건강한 성인을 대상으로 기능적 근적외선 분광법(fNIRS)을 이용하여 우세손과 비우세손에 따른 뇌 활성화도의 차이를 알아보고자 하였다. 우세손, 비우세손 총 2가지 조건에서 상자와 나무토막검사(BBT)를 실시하였다. 실험을 진행하는 동안 fNIRS을 이용하여 뇌 활성도를 측정하였으며, 실험이 종료된 후 nirsLAB v2019.04 소프트웨어를 사용하여 신호를 분석하였다. 그 결과 우세손을 사용한 경우 10명 중 6명이 우세손과 관련 있는 대뇌반구의 활성화를 보였고, 비우세손을 사용한 경우는 10명 중 3명만이 비우세손과 관련 있는 대뇌반구의 활성화를 보였다. 즉, 우세손, 비우세손 모두 우세손과 관련 있는 대뇌반구가 좀 더 활성화되었음을 확인하였다. 따라서 우세손을 알기 어려운 감각처리장애를 가진 아동들에게 fNIRS을 적용할 수 있는 기초적 자료로 사용될 수 있으리라 사료된다.

Information obtainable from transmission measurements of carbohydrates in the range from 200 to 1700 nm using water, heavy water ($D_20$) or dimethylsulfoxide (DMSO) as solvents

  • Bernhard Tauscher;Robert B.Jordan;Peter Butz;Carola Merkel
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1518-1518
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    • 2001
  • In the area of the destruction-free NIR analysis of fruit and vegetables development has not yet progressed as far as in grain and similar products. One reason for that is, that in contrast to grains, in fruit and vegetables water appears as the outstanding main-component making up typically 80% by weight of the fruit. Of the M absorption spectrum of pure water the bands at 1450, 970 and 760 nm are the first, second and third overtones respectively of O-H stretch while those at 1940 and 1190 are combination bands involving O-H stretch and O-H bend. The choice of band for spectrometry is governed by considerations of sensitivity and selectivity. The overtone bands are satisfactory for use in moisture measurements from 0 to 4 % depending on path length. Measurements in fruits and vegetables at wavelength areas that are also important for the determination of carbohydrates (sucrose, glucose, fructose) often lead to total absorption in the presence of significant water even if short path lengths are possible. In this work model systems are used containing different carbohydrates in solvents like heavy water (D$_2$O) or dimethylsulfoxide (DMSO) that do not contain O-H functional groups.

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Prefrontal Cortex Activation during Diaphragmatic Breathing in Women with Fibromyalgia: An fNIRS Case Report

  • Hyunjoong Kim;Jihye Jung;Seungwon Lee
    • Physical Therapy Rehabilitation Science
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    • 제12권3호
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    • pp.334-339
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    • 2023
  • Objective: The present study is designed to delve deeper into the realm of fibromyalgia (FM) symptom management by investigating the effects of diaphragmatic breathing on the prefrontal cortex (PFC) in women diagnosed with FM. Using functional near-infrared spectroscopy (fNIRS), the study aims to capture real-time PFC activation patterns during the practice of diaphragmatic breathing. The overarching objective is to identify and understand the underlying neural mechanisms that may contribute to the observed clinical benefits of this relaxation technique. Design: A case report Methods: To achieve this, a twofold approach was adopted: First, the patient's breathing patterns were meticulously examined to detect any aberrations. Following this, fNIRS was employed, focusing on the activation dynamics within the PFC. Results: Our examination unveiled a notable breathing pattern disorder inherent to the FM patient. More intriguingly, the fNIRS analysis offered compelling insights: the ventrolateral prefrontal cortex (VLPFC) displayed increased activation. In stark contrast, regions of the anterior prefrontal cortex (aPFC) and orbitofrontal cortex (OFC) manifested decreased activity, especially when benchmarked against typical activations seen in healthy adults. Conclusions: These findings, derived from a nuanced examination of FM, underscore the condition's multifaceted nature. They highlight the imperative to look beyond conventional symptomatology and appreciate the profound neurological and physiological intricacies that define FM.

뇌성마비 소아에 대한 중추신경계재활치료 및 피내침 병용치료에 관한 연구 - 기능성 적외선 분광법(fNIRS)를 이용한 예비 연구 - (Integrative medicine rehabilitation of simultaneous intra-dermal acupuncture (IDA) and neurodevelopmental treatment (NDT) for children with cerebral palsy: Pilot Study of Functional Near-Infrared Spectroscopy)

  • 장석주;남연교;김지현;고문정;권범선;임지연;민상연
    • 대한한방소아과학회지
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    • 제35권1호
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    • pp.139-147
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    • 2021
  • Objectives The purpose of this study is to investigate differences in brain activities when Neurodevelopmental treatment (NDT) is used alone compare to NDT is combined with intradermal acupuncture (IDA) treatment, using functional infrared spectroscopy (fNIRS) Methods Three children less than 7 year-old with cerebral palsy were participated. On their first visit, only NDT was used. After a week, they were treated with both NDT and IDA. During the treatment, fNIRS was used to measure any changes in their brain activities. Results In first patient with NDT, oxyhemoglobin level was increased during Standing exercise and Gait training compared to resting state. When the patient was treated with NDT and IDA, oxyhemoglobin level was decreased during Standing exercise and Gait training compared to resting state, and the result was significant (p<0.05). In second patient, oxyhemoglobin level was decreased in Gait training compared to resting state when NDT was used, but the level was increased when NDT and IDA were used in Gait training compared to resting state (p<0.05). In third patient, the difference in oxyhemoglobin levels between Gait training and resting state was significant (p<0.05). Conclusions Treatment involving both NDT and IDA has more potential to improve brain activities compared to that of NDT alone, and no adverse effect was reported. In order to confirm the finding, larger scale randomized controlled trials are needed.