scholarly journals Intensity Revival of Weak Symmetric Infrared Band is Possible in Ubiquinone Molecules through the Asymmetric Site-specific Isotope Labeling

2015 ◽  
Vol 5 ◽  
pp. 39-46
Author(s):  
Hari Prasad Lamichhane
Keyword(s):  
Spectral Region ◽  
Isotope Labeling ◽  
Spectral Band ◽  
Polarizable Continuum Model ◽  
Infrared Band ◽  
Site Specific ◽  
13C Labeling ◽  
Spectral Bands ◽  
Weak Intensity ◽  
Ir Bands

Modifications of Infrared (IR) spectral bands of ubiquinone molecule (UQ1) upon site-specific 13C labeling at the C5 or C6 position are studied in CCl4 using Gaussian 03. Polarizable continuum model (PCM) has been used to optimize the UQ1 molecule in solvent. The unlabeled neutral ubiquinone molecule consists of three intense IR bands in the frequency region between 1700 cm-1 to 1550 cm-1. The symmetric fourth band in this spectral region does not appear in the spectrum because of very weak intensity. However, site-specific 13C labeling at C5 or C6 position removes the molecular symmetry and hence there appear four equivalent IR bands in the spectral region thus considered. This observation explains why there appears an extra spectral band in the experimental spectra observed by Brudler, R. et al [1].The Himalayan Physics Year 5, Vol. 5, Kartik 2071 (Nov 2014)Page: 39-46

scholarly journals TOPOGRAPHIC EFFECT ON SPECTRAL VEGETATION INDICES FROM LANDSAT TM DATA: IS TOPOGRAPHIC CORRECTION NECESSARY?

2016 ◽  
Vol 22 (1) ◽  
pp. 95-107 ◽  
Author(s):  
Eder Paulo Moreira* ◽  
Márcio de Morisson Valeriano ◽  
Ieda Del Arco Sanches ◽  
Antonio Roberto Formaggio
Keyword(s):  
Near Infrared ◽  
Incidence Angle ◽  
Spectral Band ◽  
Vegetation Indices ◽  
Topographic Effect ◽  
Topographic Correction ◽  
Spectral Bands ◽  
Spectral Vegetation Indices ◽  
Current Availability ◽  
Elevation Model

The full potentiality of spectral vegetation indices (VIs) can only be evaluated after removing topographic, atmospheric and soil background effects from radiometric data. Concerning the former effect, the topographic effect was barely investigated in the context of VIs, despite the current availability correction methods and Digital elevation Model (DEM). In this study, we performed topographic correction on Landsat 5 TM spectral bands and evaluated the topographic effect on four VIs: NDVI, RVI, EVI and SAVI. The evaluation was based on analyses of mean and standard deviation of VIs and TM band 4 (near-infrared), and on linear regression analyses between these variables and the cosine of the solar incidence angle on terrain surface (cos i). The results indicated that VIs are less sensitive to topographic effect than the uncorrected spectral band. Among VIs, NDVI and RVI were less sensitive to topographic effect than EVI and SAVI. All VIs showed to be fully independent of topographic effect only after correction. It can be concluded that the topographic correction is required for a consistent reduction of the topographic effect on the VIs from rugged terrain.

Differential Isotope Labeling of Glycopeptides for Accurate Determination of Differences in Site-Specific Glycosylation

2015 ◽  
Vol 15 (1) ◽  
pp. 326-331 ◽  
Author(s):  
Martin Pabst ◽  
Iva Benešová ◽  
Stephan R. Fagerer ◽  
Mathias Jacobsen ◽  
Klaus Eyer ◽  
...  
Keyword(s):  
Isotope Labeling ◽  
Accurate Determination ◽  
Site Specific

scholarly journals Radiative Properties and Numerical Modeling of C4F7N-CO2-O2 Thermal Plasma

2019 ◽  
Vol 6 (2) ◽  
pp. 144-147
Author(s):  
M. Gnybida ◽  
Ch. Ruempler ◽  
V. R. T. Narayanan
Keyword(s):  
Thermal Plasma ◽  
Spectral Band ◽  
Optimization Procedure ◽  
Optimal Number ◽  
Radiative Properties ◽  
Absorption Coefficients ◽  
Medium Voltage ◽  
Spectral Bands ◽  
Computational Fluid Dynamics Cfd ◽  
Low Global Warming Potential

C<sub>4</sub>F<sub>7</sub>N and C<sub>4</sub>F<sub>7</sub>N-CO<sub>2</sub> mixtures are considered as alternatives to SF<sub>6</sub> for use in medium voltage gas insulated switchgear applications (GIS), due to the low global warming potential and good dielectric properties of C<sub>4</sub>F<sub>7</sub>N. Current work is focused on the calculation of radiative properties (absorption coefficients) of C<sub>4</sub>F<sub>7</sub>N-CO<sub>2</sub> thermal plasma and computational fluid dynamics (CFD) simulations of free burning C<sub>4</sub>F<sub>7</sub>N-CO<sub>2</sub> arcs that are stabilized by natural convection. Absorption coefficients of C<sub>4</sub>F<sub>7</sub>N-CO<sub>2</sub> plasma used in the CFD model are derived from spectral absorption coefficients by Planck averaging. An optimization procedure has been applied to find the optimal number of spectral bands as well as spectral band interval boundaries. Radiation and flow model results for C<sub>4</sub>F<sub>7</sub>N-CO<sub>2</sub> in comparison to SF<sub>6</sub> and air are provided and discussed.

scholarly journals Radiometric Calibration of UAV Remote Sensing Image with Spectral Angle Constraint

2019 ◽  
Vol 11 (11) ◽  
pp. 1291 ◽  
Author(s):  
Kaiqiu Xu ◽  
Yan Gong ◽  
Shenghui Fang ◽  
Ke Wang ◽  
Zhiheng Lin ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Near Infrared ◽  
Linear Method ◽  
Radiometric Calibration ◽  
Constraint Condition ◽  
Infrared Band ◽  
Spectral Bands ◽  
Quantitative Remote Sensing ◽  
Spectral Channels ◽  
Spectral Angle

In recent years, the acquisition of high-resolution multi-spectral images by unmanned aerial vehicles (UAV) for quantitative remote sensing research has attracted more and more attention, and radiometric calibration is the premise and key to the quantification of remote sensing information. The traditional empirical linear method independently calibrates each channel, ignoring the correlation between spectral bands. However, the correlation between spectral bands is very valuable information, which becomes more prominent as the number of spectral channels increases. Based on the empirical linear method, this paper introduces the constraint condition of spectral angle, and makes full use of the information of each band for radiometric calibration. The results show that, compared with the empirical linear method, the proposed method can effectively improve the accuracy of radiometric calibration, with the improvement range of Mean Relative Percent Error (MRPE) being more than 3% in the range of visible band and within 1% in the range of near-infrared band. Besides, the method has great advantages in agricultural remote sensing quantitative inversion.

scholarly journals Improved strategy for isoleucine 1H/13C methyl labeling in Pichia pastoris

2019 ◽  
Vol 73 (12) ◽  
pp. 687-697 ◽  
Author(s):  
Rustam Ali ◽  
Lindsay D. Clark ◽  
Jacob A. Zahm ◽  
Andrew Lemoff ◽  
Karthik Ramesh ◽  
...  
Keyword(s):  
Pichia Pastoris ◽  
Isotope Labeling ◽  
Protein Complexes ◽  
Cost Effective ◽  
Specific Protein ◽  
Site Specific ◽  
Methyl Labeling ◽  
Structure And Dynamics ◽  
Eukaryotic Proteins ◽  
The Cost

Abstract Site specific methyl labeling combined with methyl TROSY offers a powerful NMR approach to study structure and dynamics of proteins and protein complexes of high molecular weight. Robust and cost-effective methods have been developed for site specific protein 1H/13C methyl labeling in an otherwise deuterated background in bacteria. However, bacterial systems are not suitable for expression and isotope labeling of many eukaryotic and membrane proteins. The yeast Pichia pastoris (P. pastoris) is a commonly used host for expression of eukaryotic proteins, and site-specific methyl labeling of perdeuterated eukaryotic proteins has recently been achieved with this system. However, the practical utility of methyl labeling and deuteration in P. pastoris is limited by high costs. Here, we describe an improved method for 1H/13C-labeling of the δ-methyl group of isoleucine residues in a perdeuterated background, which reduces the cost by ≥ 50% without compromising the efficiency of isotope enrichment. We have successfully implemented this method to label actin and a G-protein coupled receptor. Our approach will facilitate studies of the structure and dynamics of eukaryotic proteins by NMR spectroscopy.

scholarly journals Covering Graphs, Magnetic Spectral Gaps and Applications to Polymers and Nanoribbons

Symmetry ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1163 ◽  
Author(s):  
John Stewart Fabila-Carrasco ◽  
Fernando Lledó
Keyword(s):  
Magnetic Field ◽  
Control Parameter ◽  
Spectral Band ◽  
Sufficient Conditions ◽  
Magnetic Potential ◽  
Spectral Gaps ◽  
Spectral Bands ◽  
Covering Graph ◽  
Abelian Lattice ◽  
Band Gap Structure

In this article, we analyze the spectrum of discrete magnetic Laplacians (DML) on an infinite covering graph G ˜ → G = G ˜ / Γ with (Abelian) lattice group Γ and periodic magnetic potential β ˜ . We give sufficient conditions for the existence of spectral gaps in the spectrum of the DML and study how these depend on β ˜ . The magnetic potential can be interpreted as a control parameter for the spectral bands and gaps. We apply these results to describe the spectral band/gap structure of polymers (polyacetylene) and nanoribbons in the presence of a constant magnetic field.

scholarly journals Hypertemporal Imaging Capability of UAS Improves Photogrammetric Tree Canopy Models

2020 ◽  
Vol 12 (8) ◽  
pp. 1238 ◽  
Author(s):  
Andrew Fletcher ◽  
Richard Mather
Keyword(s):  
Forest Canopy ◽  
Near Infrared ◽  
Spectral Band ◽  
Point Clouds ◽  
Tree Canopy ◽  
Solar Elevation ◽  
Spectral Bands ◽  
Eucalyptus Forest ◽  
Dense Point ◽  
Solar Noon

Small uncrewed aerial systems (UASs) generate imagery that can provide detailed information regarding condition and change if the products are reproducible through time. Densified point clouds form the basic information for digital surface models and orthorectified mosaics, so variable dense point reconstruction will introduce uncertainty. Eucalyptus trees typically have sparse and discontinuous canopies with pendulous leaves that present a difficult target for photogrammetry software. We examine how spectral band, season, solar azimuth, elevation, and some processing settings impact completeness and reproducibility of dense point clouds for shrub swamp and Eucalyptus forest canopy. At the study site near solar noon, selecting near infrared camera increased projected tree canopy fourfold, and dense point features more than 2 m above ground were increased sixfold compared to red spectral bands. Near infrared (NIR) imagery improved projected and total dense features two- and threefold, respectively, compared to default green band imagery. The lowest solar elevation captured (25°) consistently improved canopy feature reconstruction in all spectral bands. Although low solar elevations are typically avoided for radiometric reasons, we demonstrate that these conditions improve the detection and reconstruction of complex tree canopy features in natural Eucalyptus forests. Combining imagery sets captured at different solar elevations improved the reproducibility of dense point clouds between seasons. Total dense point cloud features reconstructed were increased by almost 10 million points (20%) when imagery used was NIR combining solar noon and low solar elevation imagery. It is possible to use agricultural multispectral camera rigs to reconstruct Eucalyptus tree canopy and shrub swamp by combining imagery and selecting appropriate spectral bands for processing.

Gradual H/D substitution in synthetic germanium bearing talcs: a method for infrared band assignment

Clay Minerals ◽  
1999 ◽  
Vol 34 (2) ◽  
pp. 365-374 ◽  
Author(s):  
F. Martin ◽  
S. Petit ◽  
O. Grauby ◽  
M. P. Lavie
Keyword(s):  
Ir Spectra ◽  
Spectral Shift ◽  
Hydroxyl Groups ◽  
Ir Absorption ◽  
Infrared Band ◽  
Absorption Bands ◽  
Band Assignment ◽  
Ir Bands

AbstractThe deuteration technique was used to assign unknown infrared (IR) bands of Ge-bearing talcs. Procedures to achieve partial or complete H/D replacement in synthetic Ge-bearing (Mg, Ni and Co)-talcs have been investigated. From the spectral shift of IR absorption bands in the 4000–300 cm-1 region resulting from the H-D substitution, the IR bands of vibrations of Ge-bearing talcs could be identified and synthetic Ge-bearing talcs showed significantly different IR spectra from those for Si-talcs. After deuteration of synthetic Ge-bearing talcs, the unknown bands were attributed either to hydroxyl groups or to Ge–O vibrations of the clay skeleton, and the spectra were interpreted fully.

scholarly journals Dissection of Hydrogen Bond Interaction Network around an Iron–Sulfur Cluster by Site-Specific Isotope Labeling of Hyperthermophilic Archaeal Rieske-Type Ferredoxin

2012 ◽  
Vol 134 (48) ◽  
pp. 19731-19738 ◽  
Author(s):  
Toshio Iwasaki ◽  
Risako Fukazawa ◽  
Yoshiharu Miyajima-Nakano ◽  
Amgalanbaatar Baldansuren ◽  
Shinichi Matsushita ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Isotope Labeling ◽  
Interaction Network ◽  
Hydrogen Bond Interaction ◽  
Iron Sulfur Cluster ◽  
Site Specific ◽  
Sulfur Cluster ◽  
Iron Sulfur ◽  
Bond Interaction

scholarly journals Infrared spectrum of HDO in water and in NaCl solution

1970 ◽  
Vol 48 (4) ◽  
pp. 607-614 ◽  
Author(s):  
Hans R. Wyss ◽  
Michael Falk
Keyword(s):  
Raman Spectrum ◽  
Infrared Spectrum ◽  
Spectral Region ◽  
High Frequency ◽  
Molecular Geometry ◽  
Wide Distribution ◽  
Molar Absorptivity ◽  
Nacl Solution ◽  
Salt Solutions ◽  
Infrared Band

The molar absorptivity of dilute HDO in water and in aqueous NaCl solutions was determined at temperatures between 10 and 85° in the spectral region from 4000 to 2000 cm−1.The infrared band profiles for the OH and OD stretching fundamentals are single-peaked and devoid of shoulders, in contrast to the high-frequency shoulders recently observed in the Raman spectrum. It is shown that such shoulders do not contradict a single-peaked distribution of OH oscillators with respect to inter-molecular geometry. Absence of resolvable sub-bands in the spectrum of HDO in concentrated salt solutions indicates a wide distribution of ion–H2O interactions, akin to the distribution of H2O–H2O interactions in water.

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