Effect of the nature of ions on the position of the absorption bands of water OH bonds in diffuse reflection spectra in the near-infrared region

2011 ◽  
Vol 85 (7) ◽  
pp. 1168-1173 ◽  
Author(s):  
E. P. Sobina ◽  
L. K. Neudachina ◽  
S. V. Medvedevskikh ◽  
M. Yu. Medvedevskikh
1994 ◽  
Vol 2 (2) ◽  
pp. 59-65 ◽  
Author(s):  
J. Todd Kuenstner ◽  
Karl H. Norris

Absorbance and first and second derivative absorbance spectra and quarter-millimolar absorptivity coefficients for hemoglobin species including oxy-, deoxy-, carboxy- and methemoglobin in the visible and in the near infrared regions from 620 nm to 2500 nm are presented. At wavelengths longer than 1500 nm, the absorbance and second derivative absorbance spectra of hemoglobin species are similar for all of the species. Absorption bands are present centred at 1690, 1740, 2056, 2170, 2290 and 2350 nm.


2009 ◽  
Vol 1173 ◽  
Author(s):  
Kazuma Tsuboi ◽  
Hidetoshi Matsumoto ◽  
Mie Minagawa ◽  
Akihiko Tanioka

AbstractIn this paper we report new excitation method of surface plasmon polariton (SPP) at air/gold interface with electrospun nanofibers. Nanofibers of polyvinylpirrolidone were electrospun onto the surface of a gold film. The observations by scanning electron microscopy and optical microscopy indicated that the average diameters of the nanofibers were about 300 nm and average sizes of pores were about 30-40 μm. Optical response of the nanofibers on gold surface was investigated by polarized reflection absorption spectroscopy (RAS). The RAS spectrum with p-polarized light showed two absorption bands while the spectrum with s-polarized light only one band. One is a band at about 520 nm that also found in the spectrum with s-polarized light. Another is a broad band in the near-infrared region which found only with p-polarized light. The peak intensity of the latter band increases with increase of incident angle of the polarized light and the peak wavelength of the band shifted to longer wavelength. These responses suggested that SPP at air/gold interface was excited with the scattering light from the electrospun nanofibers. We also found that the peak wavelength of the absorption band in near-infrared region changed with the increase of the amount of the nanofibers. This may be due to the fact that the sizes of the pores on gold surface became smaller than the propagation length of SPP, which resulted in scattering and interference of SPP.


2017 ◽  
Vol 5 (47) ◽  
pp. 12571-12584 ◽  
Author(s):  
Jing Zhou ◽  
Ju-Won Jeon ◽  
James F. Ponder ◽  
Jeffrey A. Geldmeier ◽  
Mahmoud A. Mahmoud ◽  
...  

An electrochemically tunable plasmonic system with narrow visible-NIR absorption bands was designed by synthesizing poly[(3,4-propylenedioxy)pyrrole] nanoshells onto a AuNR core.


1968 ◽  
Vol 21 (7) ◽  
pp. 1775
Author(s):  
DP Graddon ◽  
GM Mockler

Absorption spectra of compounds CoX2B2 and CoX2B4 (X = Cl, Br, I, or NCS; B = a heterocyclic base) have been obtained by reflectance and in solution in the near infrared region between 1000 and 2000 mμ. The spectra are characteristic of the stereochemistry of the metal atom: octahedral compounds have a single absorption band near 1100 mμ, e < 10; tetrahedral compounds have three overlapping absorption bands near 1100,1400, and 1700 mp, 30 < < 150. Comparisons are made with previously observed spectra of octahedral and tetrahedral species of the types CoL2+6 and CoX2-4.


Author(s):  
Rohit Singh

In molecular vibrational infrared spectroscopy, absorption spectra arise from molecular vibration and correspond to transitions between the vibrational energy levels associated with a given electronic state of the molecule. The vibrational transitions, which fall in the near infrared region, are induced through the interaction of the molecular electric dipole with the electric vector of the electromagnetic radiation. The near infrared region extends roughly from 1?m to ?10?^2 ?m. The article explains the pure vibrational absorption spectra of diatomic molecules such as HCl, HBr, HI, CO, … etc. In order to explain the vibrational spectra, diatomic molecules are treated as harmonic oscillator and anharmonic oscillator. In the harmonic oscillator model, we get only one absorption band at the wavenumber value? ?_osc corresponding to frequency of oscillation?_osc while in the actual experimental data, there are many absorption bands corresponding to wave numbers slightly lesser than ? ?_osc, 2? ?_osc, 3? ?_osc, ……..The occurrence of these additional bandsis attributed to the selection rule ?v=±2, ±3, ±4, ……The additional bands are having lesser intensity and are called overtone bands.


RSC Advances ◽  
2018 ◽  
Vol 8 (25) ◽  
pp. 14072-14083 ◽  
Author(s):  
Hidemitsu Uno ◽  
Takayuki Honda ◽  
Manami Kitatsuka ◽  
Shogo Hiraoka ◽  
Shigeki Mori ◽  
...  

Benzene-fused bis(acenaphthoBODIPY)s prepared by retro-Diels–Alder reaction of bicyclo[2.2.2]octadiene-fused precursors showed strong absorption bands in the near-infrared region and very weak absorptions in the visible region.


2012 ◽  
Vol 1407 ◽  
Author(s):  
Yuichi Kato ◽  
Ayaka Inoue ◽  
Naotoshi Nakashima ◽  
Yasuro Niidome

ABSTRACTExchange of solubilizers adsorbed on single-walled carbon nanotubes (CNTs) is probed by analysis of the peak shifts of the absorption bands of CNTs in the near-infrared region. Equilibrium constants and thermodynamic parameters of the exchange of sodium cholate for DNA (15-mers of oligo-DNAs, cytosine) on CNTs of different chirality are determined.


2020 ◽  
Vol 50 (1) ◽  
pp. 159-166
Author(s):  
Vitaly Novikov ◽  
Andrey Baryshnikov ◽  
Kira Rysakova ◽  
Nadezhda Shumskaya ◽  
Olga Uzbekova

Introduction. Near-infrared (NIR) spectroscopy is a modern instrumental method for the quantitative and qualitative analysis of various objects. The method for analyzing the NIR spectra of diffuse reflection was successfully used to identify plant and animal species, drugs, etc. The issue of identifying objects of marine fishery is currently extremely important for modern fisheries, environmental monitoring, and identifying counterfeit products. The research objective was to identify the fish taxa using the discriminant analysis of reflection in the NIR region. Study objects and methods. The research featured 25 dried and defatted muscle tissue samples taken from different species of marine fish caught in the North Fishing Basin. The spectra were measured using a Fourier IR-spectrophotometer Shimadzu IRTracer-100 with a diffuse reflection measuring instrument. Measurements were carried out in the range from 700 to 7,000 cm–1. Mathematical processing of the spectra was performed using the MagicPlot Pro program ver. 2.9 (Magicplot Systems, LLC), while the statistical program IBM SPSS Statistics ver. 25 (IBM Corp., USA) was exploited to perform the linear discriminant analysis. Results and discussion. The spectra of diffuse reflection of NIR radiation were measured for 25 samples of marine fish species of different taxa caught in the North Fishing Basin. The range of 3,700 to 6,700 cm–1 was selected to assess the proximity of spectra in linear discriminant analysis. In this range, the team identified 19 spectral peaks, which made a significant contribution to canonical discriminatory functions. The resulting canonical discriminatory functions made it possible to divide the objects into eight nonoverlapping groups corresponding to each biological group of the fish. The analysis was based on a comparison of Mahalanobis distance between the group centroids and the NIR spectra of each studied fish species. The minimum Mahalanobis distance between the nearest groups was statistically significant. Conclusion. The research proved the possibility of taxonomic identification of marine fish based on measuring the spectral characteristics of their muscle tissue proteins in the range of 3,700 to 6,700 cm–1 of near-infrared region and classification by linear discriminant analysis.


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