Porphyrazines with annulated diazepine rings. 5. Near-IR-absorbing tetrakis(6,7-dihydro-1H-1,4-diazepino)porphyrazines and effects of acid solvation on their spectral properties

2020 ◽  
Vol 44 (42) ◽  
pp. 18362-18371
Author(s):  
Ivan A. Skvortsov ◽  
Alina M. Fazlyeva ◽  
Ilya A. Khodov ◽  
Pavel A. Stuzhin
Keyword(s):  
Spectral Properties ◽  
Spectral Response ◽  
Near Ir ◽  
Medium Acidity

Novel porphyrazines bearing fused 6,7-dihydro-1H-1,4-diazepine rings were synthesized and their spectral response on the change of medium acidity was demonstrated.

Spectral properties of the tubuloglomerular feedback system

1997 ◽  
Vol 273 (4) ◽  
pp. F635-F649 ◽  
Author(s):  
H. E. Layton ◽  
E. Bruce Pitman ◽  
Leon C. Moore
Keyword(s):  
Transit Time ◽  
Spectral Properties ◽  
Response Curve ◽  
Feedback Loop ◽  
Spectral Response ◽  
Power Spectra ◽  
Tubuloglomerular Feedback ◽  
Feedback Gain ◽  
Thick Ascending Limb ◽  
Closed Feedback Loop

A simple mathematical model was used to investigate the spectral properties of the tubuloglomerular feedback (TGF) system. A perturbation, consisting of small-amplitude broad-band forcing, was applied to simulated thick ascending limb (TAL) flow, and the resulting spectral response of the TGF pathway was assessed by computing a power spectrum from resulting TGF-regulated TAL flow. Power spectra were computed for both open- and closed-feedback-loop cases. Open-feedback-loop power spectra are consistent with a mathematical analysis that predicts a nodal pattern in TAL frequency response, with nodes corresponding to frequencies where oscillatory flow has a TAL transit time that equals the steady-state fluid transit time. Closed-feedback-loop spectra are dominated by the open-loop spectral response, provided that γ, the magnitude of feedback gain, is less than the critical value γc required for emergence of a sustained TGF-mediated oscillation. For γ exceeding γc, closed-loop spectra have peaks corresponding to the fundamental frequency of the TGF-mediated oscillation and its harmonics. The harmonics, expressed in a nonsinusoidal waveform for tubular flow, are introduced by nonlinear elements of the TGF pathway, notably TAL transit time and the TGF response curve. The effect of transit time on the flow waveform leads to crests that are broader than troughs and to an asymmetry in the magnitudes of increasing and decreasing slopes. For feedback gain magnitude that is sufficiently large, the TGF response curve tends to give a square waveshape to the waveform. Published waveforms and power spectra of in vivo TGF oscillations have features consistent with the predictions of this analysis.

Near IR Sensitization of Organic Bulk Heterojunction Solar Cells: Towards Optimization of the Spectral Response of Organic Solar Cells

2010 ◽  
Vol 20 (2) ◽  
pp. 338-346 ◽  
Author(s):  
Markus Koppe ◽  
Hans-Joachim Egelhaaf ◽  
Gilles Dennler ◽  
Markus C. Scharber ◽  
Christoph J. Brabec ◽  
...  
Keyword(s):  
Solar Cells ◽  
Organic Solar Cells ◽  
Bulk Heterojunction ◽  
Spectral Response ◽  
Heterojunction Solar Cells ◽  
Bulk Heterojunction Solar Cells ◽  
Near Ir

scholarly journals Implications of temperature-dependent near-IR spectral properties of common minerals and meteorites for remote sensing of asteroids

1999 ◽  
Vol 26 (12) ◽  
pp. 1661-1664 ◽  
Author(s):  
J. L. Hinrichs ◽  
P. G. Lucey ◽  
M. S. Robinson ◽  
A. Meibom ◽  
A. N. Krot
Keyword(s):  
Remote Sensing ◽  
Spectral Properties ◽  
Temperature Dependent ◽  
Near Ir

scholarly journals SPECTRAL PROPERTIES OF ZINC AND COBALT MESO-TETRAPHENYLPORPHYRINS IN POLYMER FILMS

2020 ◽  
Vol 63 (10) ◽  
pp. 110-116
Author(s):  
Maria Е. Glazkova ◽  
Maria V. Petrova ◽  
Yuliya S. Rodina ◽  
Sofia S. Rodina ◽  
Тatiana А. Аgeeva
Keyword(s):  
Benzoyl Peroxide ◽  
Polymer Matrix ◽  
Spectral Properties ◽  
Electronic Absorption Spectra ◽  
Bathochromic Shift ◽  
Fluorescent Properties ◽  
Absorption Bands ◽  
Near Ir ◽  
Residual Amount ◽  
First Time

The results of studying the spectral properties of zinc and cobalt meso-tetraphenyl-porphyrins included as the modifiers in polymethylmethacrylate, polystyrene and polyvinylchloride films are presented in this article for the first time. It was established that an inert polymer matrix of polyvinylchloride, block polystyrene and polymethylmethacrylate does not affect the spectral properties of tetrapyrrole macroheterocycles, which are included in it. In this case, insignificant bathochromic shift of the absorption bands of the metal complexes in the modified films is recorded, which is probably due to the presence of intermolecular interaction of the metalloporphyrin with the polymer matrix. The method of polymer producing is important for modification of polystyrene or polymethyl methacrylate films. The ignificant changes are observed in the electronic spectra of metalloporphyrins due to the interaction between the modifier and the residual amount of the radical polymerization initiator (benzoyl peroxide) used in the preparation of polymers. Earlier studies showed that the interaction of benzoyl peroxide with zinc and cobalt meso-tetraphenylporphyrinates in solution leads to the formation of the corresponding metalloisoporphyrinates. In this work, the possibility of such structures formation in a polymer matrix is shown for the first time. In this case, in the electronic absorption spectra of the modified films, as in solutions, bands appear in the near IR region. The fluorescent properties of modified films have been studied. It was shown that in the absence of interaction between the components in the film, metalloporphyrins introduced into the polymer matrix retain their ability to fluorescence.

Molten salt synthesis, visible and near-IR region spectral properties of europium or neodymium doped CoNb2O6 columbite niobate

2015 ◽  
Vol 44 (12) ◽  
pp. 5379-5385 ◽  
Author(s):  
Mete Kaan Ekmekçi ◽  
Murat Erdem ◽  
Ali Sadi Başak
Keyword(s):  
Molten Salt ◽  
Spectral Properties ◽  
Emission Spectra ◽  
Molten Salt Synthesis ◽  
Near Ir

Emission spectra of the phosphor powders for the 5D0→7F2 transition in CoNb2O6 powders doped with Eu3+ at 300 K.

Near-Infrared Heptamethine Cyanine Dyes: A New Tracer for Solid-Phase Immunoassays

1997 ◽  
Vol 51 (6) ◽  
pp. 836-843 ◽  
Author(s):  
Richard J. Williams ◽  
Jose Mauro Peralta ◽  
Victor C. W. Tsang ◽  
Narasimhachari Narayanan ◽  
Guillermo A. Casay ◽  
...  
Keyword(s):  
Spectral Properties ◽  
Near Infrared ◽  
Solid Phase ◽  
Human Immunoglobulin ◽  
Minimal Amount ◽  
Human Antibody ◽  
Near Ir ◽  
Solid Phase Immunoassay ◽  
Bioanalytical Applications ◽  
Aqueous Conditions

Near-infrared (near-IR) fluorescence has been used to develop a solid-phase immunoassay that detects trace amounts of human immunoglobulin (HuIgG). Various concentrations of HuIgG bound to a nitrocellulose surface were determined from the fluorescence generated by near-IR labeled goat anti-human antibody (GAHG) bound to the HuIgG. The GAHG was labeled with a heptamethine cyanine fluorophore that has spectral properties in the near-IR region (above 780 nm). These fluorophores are versatile because they can be modified for several bioanalytical applications. Fluorescence was detected with a near-IR fluorescence instrument previously developed in the laboratory. Two cyanine fluorophore labels were evaluated for the ability to selectively bind to GAHG on a nitrocellulose matrix with a minimal amount of background interference. After the most appropriate near-IR fluorophore was selected, the labeling of GAHG was optimized under aqueous conditions. The most effective GAHG–dye conjugates were used to develop an immunoassay to detect various concentrations of HuIgG. The results are presented, here. Solutions of HuIgG with concentrations as low as 10−10 molar have been detected with a minimum of interference.

Heteroleptic naphthalo-phthalocyaninates of lutetium: synthesis and spectral and conductivity properties

2015 ◽  
Vol 44 (17) ◽  
pp. 7973-7981 ◽  
Author(s):  
Tatiana V. Dubinina ◽  
Anton D. Kosov ◽  
Elizaveta F. Petrusevich ◽  
Sergey S. Maklakov ◽  
Nataliya E. Borisova ◽  
...  
Keyword(s):  
Spectral Properties ◽  
Near Ir ◽  
Heteroleptic Complexes ◽  
High Yields

A series of novel near-IR absorbing heteroleptic complexes were obtained with high yields. The correlation between the nature of the substituents and spectral properties of the target complexes was determined.

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