Review of Chemical Reactivity of Singlet Oxygen with Organic Fuels and Contaminants

2020 ◽  
Author(s):  
Jomana Al‐Nu'airat ◽  
Ibukun Oluwoye ◽  
Nassim Zeinali ◽  
Mohammednoor Altarawneh ◽  
Bogdan Z. Dlugogorski
Keyword(s):  
Singlet Oxygen ◽  
Chemical Reactivity ◽  
Organic Fuels

scholarly journals Photophysical Detection of Singlet Oxygen

2021 ◽  
Author(s):  
Arnab Maity
Keyword(s):  
Singlet Oxygen ◽  
Indirect Method ◽  
Chemical Reactivity ◽  
Direct Method ◽  
Therapeutic Process ◽  
Fluorescence Emission ◽  
Electronically Excited ◽  
Detection Probe ◽  
Current Research Interest

The chemical reactivity of singlet oxygen (1O2) (SO) derives from its electronically excited state. Being a unique reactive oxygen species SO takes part in many important atmospheric, biological physical, chemical, and therapeutic process and attracted current research interest. To understand the mechanistic pathways in various process the detection and quantification of SO is very important. The direct method of detection is very challenging due to its highly reactive nature. Only direct method of determination of phosphorescence of SO at 1270 nm has been utilised but that also puts some limitation due to very low luminescence quantum yield. Indirect method using UV–Vis spectrophotometric, fluorescent and chemiluminescent probes has been extensively studied for this purpose. Elucidation of various mechanistic processes improvised the use of sophisticated spectroscopic detection probe for SO have been discussed in a simple and lucid manner in this article through citation of literature examples. Four major spectroscopic methods i.e. spectrophotometry, fluorescence, emission and chemiluminescence are elaborately discussed with special emphasis to chemical probes having high selectivity and sensitivity for SO.

Chemical Reactivity of Sigma Singlet Oxygen O2(1Σg+)

1997 ◽  
Vol 101 (31) ◽  
pp. 5672-5677 ◽  
Author(s):  
Marcus Bodesheim ◽  
Reinhard Schmidt
Keyword(s):  
Singlet Oxygen ◽  
Chemical Reactivity

scholarly journals Photochemistry and Spectroscopy of Singlet Oxygen in Solvents. Recent Advances which Support the Old Theory

2016 ◽  
Vol 10 (4s) ◽  
pp. 519-530 ◽  
Author(s):  
Boris Minaev ◽  
Keyword(s):  
Singlet Oxygen ◽  
Chemical Reactivity ◽  
Dye Sensitization ◽  
Medical Treatments ◽  
New Synthesis ◽  
Semiempirical Theory ◽  
Wide Range ◽  
Direct Laser ◽  
Important Intermediate ◽  
Specific Reactions

Molecular oxygen is a paramagnetic gas with the triplet O2( ) ground state which exhibits just sluggish chemical reactivity in the absence of radical sources. In contrast, the excited metastable singlet oxygen O2( ) is highly reactive; it can oxygenate organic molecules in a wide range of specific reactions which differ from those of the usual triplet oxygen of the air. This makes the singlet oxygen an attractive reagent for new synthesis and even for medical treatments in photodynamic therapy. As an important intermediate O2( ) has attracted great attention of chemists during half-century studies of its reactivity and spectroscopy, but unusual properties of singlet oxygen makes it difficult to unravel all mysterious features. The semiempirical theory of spin-orbit coupling in dioxygen and in collision complexes of O2 with diamagnetic molecules proposed in 1982 year has explained and predicted many photochemical and spectral properties of dioxygen produced by the dye sensitization in solvents. Recent experiments with direct laser excitation of O2 in solvents provide a complete support of the old theory. The present review scrutinizes the whole story of development and experimental verification of this theory.

Spatially Resolved Photoelectron Spectroscopy: Recent Progress and Future Plans

1990 ◽  
Vol 48 (2) ◽  
pp. 388-389
Author(s):  
A. M. Bradshaw
Keyword(s):  
Photoelectron Spectroscopy ◽  
Chemical Reactivity ◽  
Target Material ◽  
Orbital Energy ◽  
Light Sources ◽  
Analytical Technique ◽  
Hartree Fock ◽  
Spatially Resolved ◽  
Koopmans Theorem ◽  
Surface Analytical Technique

X-ray photoelectron spectroscopy (XPS or ESCA) was not developed by Siegbahn and co-workers as a surface analytical technique, but rather as a general probe of electronic structure and chemical reactivity. The method is based on the phenomenon of photoionisation: The absorption of monochromatic radiation in the target material (free atoms, molecules, solids or liquids) causes electrons to be injected into the vacuum continuum. Pseudo-monochromatic laboratory light sources (e.g. AlKα) have mostly been used hitherto for this excitation; in recent years synchrotron radiation has become increasingly important. A kinetic energy analysis of the so-called photoelectrons gives rise to a spectrum which consists of a series of lines corresponding to each discrete core and valence level of the system. The measured binding energy, EB, given by EB = hv−EK, where EK is the kineticenergy relative to the vacuum level, may be equated with the orbital energy derived from a Hartree-Fock SCF calculation of the system under consideration (Koopmans theorem).

Cluster analysis for large data sets: applications to individual aerosol particles from the mid-pacific

1992 ◽  
Vol 50 (2) ◽  
pp. 1488-1489
Author(s):  
Thomas W. Shattuck ◽  
James R. Anderson ◽  
Neil W. Tindale ◽  
Peter R. Buseck
Keyword(s):  
Cluster Analysis ◽  
Chemical Reactivity ◽  
Large Data ◽  
Large Data Sets ◽  
Particle Analysis ◽  
Data Sets ◽  
Halogen Chemistry ◽  
Complete Study ◽  
Components Analysis ◽  
Automated Scanning

Individual particle analysis involves the study of tens of thousands of particles using automated scanning electron microscopy and elemental analysis by energy-dispersive, x-ray emission spectroscopy (EDS). EDS produces large data sets that must be analyzed using multi-variate statistical techniques. A complete study uses cluster analysis, discriminant analysis, and factor or principal components analysis (PCA). The three techniques are used in the study of particles sampled during the FeLine cruise to the mid-Pacific ocean in the summer of 1990. The mid-Pacific aerosol provides information on long range particle transport, iron deposition, sea salt ageing, and halogen chemistry.Aerosol particle data sets suffer from a number of difficulties for pattern recognition using cluster analysis. There is a great disparity in the number of observations per cluster and the range of the variables in each cluster. The variables are not normally distributed, they are subject to considerable experimental error, and many values are zero, because of finite detection limits. Many of the clusters show considerable overlap, because of natural variability, agglomeration, and chemical reactivity.

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