General strategy for tuning the Stokes shifts of near infrared cyanine dyes

2020 ◽  
Vol 8 (47) ◽  
pp. 16769-16773
Author(s):  
Jun Zhang ◽  
Mehdi Moemeni ◽  
Chenchen Yang ◽  
Fangchun Liang ◽  
Wei-Tao Peng ◽  
...  
Keyword(s):  
Excited State ◽  
Computational Analysis ◽  
Near Infrared ◽  
Spectral Characteristics ◽  
Cyanine Dyes ◽  
General Strategy ◽  
Stokes Shifts

A series of amine substituted cyanines show spectral characteristics that are dependent on the structure of the substituted amine, with Stokes shifts that range from 24–180 nm. Computational analysis informs on the ground and excited state structures.

Near-Infrared Combination and Overtone Bands of CH in CHX3, CHX2—CHX2, and CHX2—CX2—CHX2

2005 ◽  
Vol 59 (11) ◽  
pp. 1393-1398 ◽  
Author(s):  
Reikichi Iwamoto ◽  
Akishi Nara ◽  
Toshihiko Matsuda
Keyword(s):  
Excited State ◽  
Near Infrared ◽  
Present Report ◽  
Spectral Characteristics ◽  
The Other ◽  
Coupled Modes ◽  
Third Order ◽  
The Third ◽  
Combination Bands ◽  
Deformation Modes

In the present report we studied spectral characteristics of the near-infrared combination and overtone bands of CH vibrations of a CH sequence. The near-infrared bands of the CH in CHX3 (X, halogen), which were interpreted in terms of the CH stretching and CH deformation fundamentals without any ambiguity, typically showed how the frequency and intensity of a combination or an overtone depend on the vibrational excited state. In the CH–C–CH of CHX2CX2CHX2, the vibrations of one CH are isolated from those of the other CH, and the combination and overtone bands were similarly interpreted as those of the CH, although each of the combination bands was split into two because of non-degeneracy of the CH deformation. In the CH–CH of CHX2CHX2, the CH deformations only have coupled modes. The first combination showed four narrowly separate bands, which were reasonably interpreted on the basis of the CH stretching and the coupled CH deformation modes. We demonstrated that the first combination of coupled modes as well as the combination of up to, at least, the third order of isolated modes have the nature of the characteristic bands.

Indolizine-Cyanine Dyes: Near Infrared Emissive Cyanine Dyes with Increased Stokes Shifts

2018 ◽  
Vol 84 (2) ◽  
pp. 687-697 ◽  
Author(s):  
Jacqueline Gayton ◽  
Shane A. Autry ◽  
William Meador ◽  
Sean R. Parkin ◽  
Glake Alton Hill ◽  
...  
Keyword(s):  
Near Infrared ◽  
Cyanine Dyes ◽  
Stokes Shifts

Near-infrared fluorescent dyes with large Stokes shifts: light generation in BODIPYs undergoing excited state intramolecular proton transfer

2017 ◽  
Vol 15 (19) ◽  
pp. 4072-4076 ◽  
Author(s):  
Qiang Fei ◽  
Xianfeng Gu ◽  
Yajing Liu ◽  
Ben Shi ◽  
Hengyan Liu ◽  
...  
Keyword(s):  
Excited State ◽  
Proton Transfer ◽  
Near Infrared ◽  
Fluorescent Dyes ◽  
Stokes Shift ◽  
Intramolecular Proton Transfer ◽  
Large Stokes Shift ◽  
Light Generation ◽  
Stokes Shifts

New ESIPT-based BODIPYs are developed to render the NIR emissions with a large Stokes shift.

A New Method for the Synthesis of Heptamethine Cyanine Dyes:  Synthesis of New Near Infrared Fluorescent Labels

1997 ◽  
Vol 62 (26) ◽  
pp. 9387-9387 ◽  
Author(s):  
Narasimhachari Narayanan ◽  
Lucjan Strekowski ◽  
Malgorzata Lipowska ◽  
Gabor Patonay
Keyword(s):  
Near Infrared ◽  
Cyanine Dyes ◽  
New Method ◽  
Fluorescent Labels

scholarly journals Realizing Near‐Infrared Laser Dyes through a Shift in Excited‐State Absorption

2021 ◽  
pp. 2001947
Author(s):  
Reiko Aoki ◽  
Ryutaro Komatsu ◽  
Kenichi Goushi ◽  
Masashi Mamada ◽  
Soo Young Ko ◽  
...  
Keyword(s):  
Excited State ◽  
Near Infrared ◽  
Excited State Absorption ◽  
Infrared Laser ◽  
Laser Dyes

Spectral characteristics of leafy spurge (Euphorbia esula) leaves and flower bracts

Weed Science ◽  
2004 ◽  
Vol 52 (4) ◽  
pp. 492-497 ◽  
Author(s):  
E. Raymond Hunt ◽  
James E. McMurtrey ◽  
Amy E. Parker Williams ◽  
Lawrence A. Corp
Keyword(s):  
Remote Sensing ◽  
High Performance ◽  
Near Infrared ◽  
Spectral Characteristics ◽  
Leafy Spurge ◽  
Hyperspectral Remote Sensing ◽  
Total Carotenoids ◽  
Physiological Basis ◽  
Infrared Wavelengths ◽  
Pigment Concentrations

Leafy spurge can be detected during flowering with either aerial photography or hyperspectral remote sensing because of the distinctive yellow-green color of the flower bracts. The spectral characteristics of flower bracts and leaves were compared with pigment concentrations to determine the physiological basis of the remote sensing signature. Compared with leaves of leafy spurge, flower bracts had lower reflectance at blue wavelengths (400 to 500 nm), greater reflectance at green, yellow, and orange wavelengths (525 to 650 nm), and approximately equal reflectances at 680 nm (red) and at near-infrared wavelengths (725 to 850 nm). Pigments from leaves and flower bracts were extracted in dimethyl sulfoxide, and the pigment concentrations were determined spectrophotometrically. Carotenoid pigments were identified using high-performance liquid chromatography. Flower bracts had 84% less chlorophylla, 82% less chlorophyllb, and 44% less total carotenoids than leaves, thus absorptance by the flower bracts should be less and the reflectance should be greater at blue and red wavelengths. The carotenoid to chlorophyll ratio of the flower bracts was approximately 1:1, explaining the hue of the flower bracts but not the value of reflectance. The primary carotenoids were lutein, β-carotene, and β-cryptoxanthin in a 3.7:1.5:1 ratio for flower bracts and in a 4.8:1.3:1 ratio for leaves, respectively. There was 10.2 μg g−1fresh weight of colorless phytofluene present in the flower bracts and none in the leaves. The fluorescence spectrum indicated high blue, red, and far-red emission for leaves compared with flower bracts. Fluorescent emissions from leaves may contribute to the higher apparent leaf reflectance in the blue and red wavelength regions. The spectral characteristics of leafy spurge are important for constructing a well-documented spectral library that could be used with hyperspectral remote sensing.

Effects of Metal Stress on Visible/Near-Infrared Reflectance Spectra of Vegetation

2011 ◽  
Vol 347-353 ◽  
pp. 2735-2738 ◽  
Author(s):  
Guang Yu Chi ◽  
Yi Shi ◽  
Xin Chen ◽  
Jian Ma ◽  
Tai Hui Zheng
Keyword(s):  
Heavy Metal ◽  
Structural Changes ◽  
Near Infrared ◽  
Leaf Surface ◽  
Spectral Response ◽  
Spectral Characteristics ◽  
Surface Characteristics ◽  
Heavy Metal Stress ◽  
Metal Stress ◽  
Near Infrared Reflectance

Vegetation which suffers from heavy metal stresses can cause changes of leaf color, shape and structural changes. The spectral characteristics of vegetation leaves is related to leaf thickness, leaf surface characteristics, the content of water, chlorophyll and other pigments. So the eco-physiology changes of plants can be reflected by spectral reflectance. Studies on the spectral response of vegetation to heavy metal stress can provide a theoretical basis for remote sensing monitoring of metal pollution in soils. In recent decades, there are substantial amounts of literature exploring the effects of heavy metals on vegetation spectra.

scholarly journals Hazardous Noxious Substance Detection Based on Ground Experiment and Hyperspectral Remote Sensing

2021 ◽  
Vol 13 (2) ◽  
pp. 318
Author(s):  
Jae-Jin Park ◽  
Kyung-Ae Park ◽  
Pierre-Yves Foucher ◽  
Philippe Deliot ◽  
Stephane Le Floch ◽  
...  
Keyword(s):  
Near Infrared ◽  
Spectral Characteristics ◽  
Chemical Properties ◽  
Principal Component ◽  
Component Analysis ◽  
Noise Removal ◽  
Vertex Component Analysis ◽  
Shortwave Infrared ◽  
Spectral Mixture ◽  
Physical And Chemical

With an increase in the overseas maritime transport of hazardous and noxious substances (HNSs), HNS-related spill accidents are on the rise. Thus, there is a need to completely understand the physical and chemical properties of HNSs. This can be achieved through establishing a library of spectral characteristics with respect to wavelengths from visible and near-infrared (VNIR) bands to shortwave infrared (SWIR) wavelengths. In this study, a ground HNS measurement experiment was conducted for artificially spilled HNS by using two hyperspectral cameras at VNIR and SWIR wavelengths. Representative HNSs such as styrene and toluene were spilled into an outdoor pool and their spectral characteristics were obtained. The relative ratio of HNS to seawater decreased and increased at 550 nm and showed different constant ratios at the SWIR wavelength. Noise removal and dimensional compression procedures were conducted by applying principal component analysis on HNS hyperspectral images. Pure HNS and seawater endmember spectra were extracted using four spectral mixture techniques—N-FINDR, pixel purity index (PPI), independent component analysis (ICA), and vertex component analysis (VCA). The accuracy of detection values of styrene and toluene through the comparison of the abundance fraction were 99.42% and 99.56%, respectively. The results of this study are useful for spectrum-based HNS detection in marine HNS accidents.

Metamaterial Window Glass for Adaptable Energy Efficiency

2013 ◽  
Author(s):  
Alex Heltzel ◽  
Tyler Mann ◽  
John R. Howell
Keyword(s):  
Energy Efficiency ◽  
Computational Analysis ◽  
Near Infrared ◽  
Window Glass ◽  
Sustainable Construction ◽  
Nanometer Scale ◽  
Glass Technology ◽  
Optical Wavelengths ◽  
Window Design ◽  
Difference Time

A computational analysis of a metamaterial (MTM) window design is presented for the purpose of increasing the energy efficiency of buildings in seasonal or cold climates. Commercial low-emissivity windows use nanometer-scale Ag films to reflect infrared energy, while retaining most transmission of optical wavelengths for functionality. An opportunity exists to further increase efficiency through a variable emissivity implementation of Ag thin-film structures. 3-D finite-difference time-domain simulations predict nonlinear absorption of near-infrared energy, providing the means to capture a substantial portion of solar energy during cold periods. The effect of various configuration parameters is quantified, with prediction of the net sustainability advantage. MTM window glass technology can be realized as a modification to current, commercial low-emissivity windows through the application of nanomanufactured films, creating the opportunity for both new and after-market sustainable construction.

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