• 제목/요약/키워드: infrared absorption

검색결과 612건 처리시간 0.032초

Synthesis of a Novel Near-Infrared Fluorescent Dye: Applications for Fluorescence Imaging in Living Cells and Animals

  • Chen, Tongbin;Lai, Yijun;Huang, Suisheng
    • Bulletin of the Korean Chemical Society
    • /
    • 제34권10호
    • /
    • pp.2937-2941
    • /
    • 2013
  • Fluorescence imaging is considered as one of the most powerful techniques for monitoring biomolecule activities in living systems. Near-infrared (NIR) light is advantageous for minimum photodamage, deep tissue penetration, and minimum background autofluorescence interference. Herein, we have developed a new NIR fluorescent dye, namely, RB-1, based on the Rhodamine B scaffold. RB-1 exhibits excellent photophysical properties including large absorption extinction coefficients, high fluorescence quantum yields, and high photostability. In particular, RB-1 displays both absorption and emission in the NIR region of the "biological window" (650-900 nm) for imaging in biological samples. RB-1 shows absorption maximum at 614 nm (500-725 nm) and emission maximum at 712 nm (650-825 nm) in ethanol, which is superior to those of traditional rhodamine B in the selected spectral region. Furthermore, applications of RB-1 for fluorescence imaging in living cells and small animals were investigated using confocal fluorescence microscopy and in vivo imaging system with a high signal-to-noise ratio (SNR = 10.1).

Heat-ray Shielding Property of Nanocomposites of Poly(acrylic acid) Doped with Copper Sulfide

  • Gotoh, Yasuo;Shibata, Kazuaki;Fujimori, Yoshie;Ohkoshi, Yutaka;Nagura, Masanobu
    • 한국섬유공학회:학술대회논문집
    • /
    • 한국섬유공학회 2003년도 The Korea-Japan Joint Symposium
    • /
    • pp.71-72
    • /
    • 2003
  • The aim of our study is to prepare nanocomposites consisting polymer/inorganic nanoparticles and investigate their physical properties as a functional material. In this study, a nanocomposite of copper sulfide (CuS) nanoparticles introduced into a poly(acrylic acid) matrix was prepared and the optical absorption property was measured. The composite exhibited strong absorption of both ultraviolet and near-infrared rays, indicating that the composite is applicable to a solar radiation shielding filter. The wavelength of the near infrared absorption was controlled from ca.1000 nm to 1700 nm by heat and acidic solution treatments.

  • PDF

부석사 조사당 벽화조사에 따른 적외선 T.V카메라 이용 (On the Mural Paintings Detectedc by through the Infrared T.V.Camera at Josadang, Busuk Temple)

  • 정광용
    • 보존과학연구
    • /
    • 통권7호
    • /
    • pp.218-236
    • /
    • 1986
  • In the fields of the cultural properties, the Infrared TV camera is being initiated to use instead of the Infrared photo film fo a better means to detect the description of drawings of the paintings. Seeing from the effect of transillumination, the Infrared TV camera with its long wave of visible spectrum that makes less absorption by the pigments and with the reflection rays passing through the base of colour layers makes it able to findbase drawing and letters. The detection range of transillumination by the infrared rays depends on the kinds of pigments, lines of the base drawing and wave length of the infrared rays. In our country, it was the first time to detect by our Conservation Science Dep't of The Research Institute of Cultural Properties by means of using Infrared TV camera to determine the mural paintings on the Josadang, Busuk Temple, resulted in an epoch-making success, that we have come to know the painting technique methods, how to treat for its conservation and making replica, reproduction, etc.

  • PDF

AKARI near Infrared spectroscopy of luminous infrared galaxies

  • 이종철;황호성;이명균
    • 천문학회보
    • /
    • 제37권1호
    • /
    • pp.50.2-50.2
    • /
    • 2012
  • We present the results of near infrared (2.5-5 micron) spectroscopy of nearby luminous infrared galaxies (LIRGs) using AKARI. The LIRG catalog is constructed from the cross-correlation between the Infrared Astronomical Satellite and the Sloan Digital Sky Survey data, and optically non-Seyfert type LIRGs are selected for main targets. We search for optically elusive active galactic nuclei (AGNs), based on the strengths of 3.3 micron polycyclic aromatic hydrocarbon emission and dust absorption features at 3-4 micron. We investigate the hidden AGN fraction as a function of the infrared luminosity and correlation between optical and near infrared star formation indicators.

  • PDF

적외선 센서를 위해 흡수층으로서 rf Magnetron Sputtering에 의해 제조된 NiCr 박막의 특성 (Characteristics of NiCr Thin Films Prepared by rf Magnetron Sputtering as Absorption Layer for Infrared Sensors)

  • 허성기;최은석;윤순길
    • 한국재료학회지
    • /
    • 제13권10호
    • /
    • pp.640-644
    • /
    • 2003
  • NiCr thin films were fabricated by rf magnetron sputtering for applying to both the top electrode and absorption layer on Pb(Zr, Ti)O$_3$(PZT) thin films for infrared sensors. The rms roughness and resistivity of NiCr films prepared with Ni power of 80 W and Cr power of 50 W showed the most stable oxidation resistance after annealing at $600^{\circ}C$ for 5 min in oxygen ambient. The rms roughness and resistivity of NiCr films annealed at $V^{\circ}C$ in oxygen ambient were about 2$0\AA$ and $70 \mu$Ω-cm, respectively. As-deposited Ni/PZT/Pt and NiCr (Ni 80 W, Cr 50 W)/PZT/Pt structures showed well saturated hysteresis loops. However, in case of the samples annealed at $500^{\circ}C$ in oxygen ambient, only NiCr/PZT/Pt showed saturated loops having a remanent polarization of 20$\mu$C/$\textrm{cm}^2$. Ultra-thin NiCr films showed a possibility as a top electrode for infrared sensors.

근적외선 업컨버전 나노입자를 이용한 광촉매 성능 향상 (Improvement of Photocatalytic Performance using Near-Infrared Upconversion Nanoparticles)

  • 박용일
    • 공업화학
    • /
    • 제32권2호
    • /
    • pp.125-131
    • /
    • 2021
  • 일반적인 반도체 기반의 광촉매는 물질 고유의 밴드갭 때문에 자외선이나 가시광선에 의해서만 활성화될 수 있고, 태양광 에너지의 약 50%를 차지하는 근적외선 영역의 에너지는 활용할 수 없다. 따라서 기존의 반도체 광촉매의 성능을 향상시키기 위해서는 자외선에서 근적외선에 이르는 넓은 영역에서 더 많은 태양광 에너지를 활용할 수 있어야 한다. 태양광의 근적외선 영역을 활용하기 위해 기존 반도체 광촉매를 업컨버전 나노입자와 결합하는 연구들이 수행되고 있다. 업컨버전 나노입자는 근적외선 광자를 여러 개 흡수하여 자외선이나 가시광선으로 변환하여 광촉매를 활성화할 수 있다. 그리고 반도체 광촉매와 업컨버전 나노입자에 플라즈모닉 금속 나노입자를 함께 결합시키면 태양광에 의한 광촉매 활성을 더욱 향상시킬 수 있다. 본 총설은 업컨버전 나노입자를 이용하여 근적외선 영역의 태양광 에너지가 광촉매의 성능 향상에 기여할 수 있도록 하는 최근의 연구결과를 바탕으로 서술하였다.

The Near-Infrared Imaging Spectroscopy to Visualize the Distribution of Sugar Content in the Flesh of a Melon

  • Tsuta, Mizuki;Sugiyama, Junichi;Sagara, Yasuyuki
    • 한국근적외분광분석학회:학술대회논문집
    • /
    • 한국근적외분광분석학회 2001년도 NIR-2001
    • /
    • pp.1526-1526
    • /
    • 2001
  • To improve the accuracy of sweetness sensor in automated sorting operations, it is necessary to clarify unevenness of the sugar content distribution within fruits. And it is expected that the technique to evaluate the content distribution in fruits contribute to the development of the near-infrared (NIR) imaging spectroscopy. Sugiyama (1999) had succeeded to visualize the distribution of the sugar content on the surface of a half-cut green fresh melon. However, this method cannot be applied to red flesh melons because it depends on information of the absorption band of chlorophyll (676 nm), which is affected by the color of the fresh. The objective of this study was to develop the universal visualization method depends on the absorption band of sugar, which can be applied to various kinds of melons and other fruits. The relationship between the sugar contents and absorption spectra of both green and red fresh melons were investigated by using a NIR spectrometer to determine the absorption band of sugar. The combination of 2$\^$nd/ derivative absorbances at 902 nm and 874 nm was highly correlated with the sugar contents. The wavelength of 902 nm is attributed to the absorption band of sugar. A cooled charge-coupled device (CCD) imaging camera which has 16 bit (65536 steps) A/D resolution was equipped with rotating band-pass filter wheel and used to capture the spectral absorption images of the flesh of a vertically half-cut red fresh melon. The advantage of the high A/D resolution in this research is that each pixel of the CCD is expected to function as a detector of the NIR spectrometer for quantitative analysis. Images at 846 nm, 874 nm, 902 nm and 930 nm were acquired using this CCD camera. Then the 2$\^$nd/ derivative absorbances at 902 nm and 874 nm at each pixel were calculated using these four images. On the other hand, parts of the same melon were extracted for capturing the images and squeezed for the measurement of sugar content. Then the calibration curve between the combination of 2$\^$nd/ derivative absorbances at 902 nm and 874 nm and sugar content was developed. The calibration method based on NIR spectroscopy techniques was applied to each pixel of the images to convert the 2$\^$nd/ derivative absorbances into the Brix sugar content. Mapping the sugar content value of each pixel with linear color scale, the distribution of the sugar content was visualized. As a result of the visualization, it was quantitatively confirmed that the Brix sugar contents are low at the near of the skin and become higher towards the seeds. This result suggests that the visualization technique by the NIR imaging spectroscopy could become a new useful method fer quality evaluation of melons.

  • PDF

AKARI IRC INFRARED 2.5-5 ㎛ SPECTROSCOPY OF NEARBY LUMINOUS INFRARED GALAXIES

  • Imanishi, Masatoshi;Nakagawa, Takao;Shirahata, Mai;Ohyama, Yoichi;Onaka, Takashi
    • 천문학논총
    • /
    • 제27권4호
    • /
    • pp.271-274
    • /
    • 2012
  • We present the result of systematic AKARI IRC infrared $2.5-5{\mu}m$ spectroscopy of >100 nearby luminous infrared galaxies, to investigate the energetic roles of starbursts and optically-elusive buried AGNs. Based on (1) the equivalent widths of the $3.3{\mu}m$ PAH emission features, (2) the optical depths of absorption features, and (3) continuum slopes, we can disentangle emission from starbursts and AGNs. We find that the energetic importance of buried AGNs increases with increasing galaxy infrared luminosities, suggesting that the AGN-starburst connections (and thereby possible AGN feedback to host galaxies) are luminosity dependent.

感光性 樹脂에 關한 硏究 (第11報). Naphthoquinone-1,2-diazide-5-sulfonyl Esters의 光分解反應 (Studies on Photosentitive Polymers (XI). Studies on Photodegradative Reaction of Naphthoquinone-1,2-diazide-5-sulfonyl Esters)

  • 심정섭;강두환
    • 대한화학회지
    • /
    • 제19권4호
    • /
    • pp.280-285
    • /
    • 1975
  • Polyglyceryl phthalate, bisphenol A-epichlorohydrin 縮重合物 및 polyvinyl alcohol의 naphthoquinone-1,2-diazide-5-sulfonyl esters(PGND, BEND 및 PVAND)에 대해 未增感 및 增感한 경우의 IR 스펙트럼을 측정하여 그들의 光分解機構를 硏究하였다. o-quinonediazide에 기인하는 C=N= 및 C=0의 흡수가 露光에 의해 減少내지는 消失하고있었고 또한 indene carboxylic acid의 C=0 흡수강도가 증가되고 있는 것으로 보아 o-quinonediazide group 이 光에 依하여 分解하여 알카리 수용액에 가용성인 indene carboxylic acid로 분해되는 것으로 추정된다. 한편, 露光時間에 대한 增感 및 未增感試料의 吸收强度의 變化를 측정하므로서 增感劑의 增感效果도 아울러 검토하였다.

  • PDF