scholarly journals Synthesis of Fluorogenic Arylureas and Amides and Their Interaction with Amines: A Competition between Turn-on Fluorescence and Organic Radicals on the Way to a Smart Label for Fish Freshness

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1404
Author(s):  
Javier García-Tojal ◽  
José V. Cuevas ◽  
María-Josefa Rojo ◽  
Borja Díaz de Greñu ◽  
Carla Hernando-Muñoz ◽  
...  
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Quantum Mechanics ◽  
Organic Radicals ◽  
Secondary Amines ◽  
Aqueous Mixtures ◽  
Paramagnetic Resonance ◽  
New Class ◽  
Turn On ◽  
Smart Label ◽  
Electron Paramagnetic

We describe the synthesis of fluorogenic arylureas and amides and their interaction with primary or secondary amines under air and light in organic-aqueous mixtures to give rise to a new class of persistent organic radicals, described on the basis of their electron paramagnetic resonance (EPR), as well as UV–vis, fluorescence, NMR, and quantum mechanics calculations, and their prospective use as multi-signal reporters in a smart label for fish freshness.

scholarly journals Distinguishing electron paramagnetic resonance signature of molecular hydrino

2021 ◽  
Author(s):  
Wilfred Hagen ◽  
Randell Mills
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Quantum Mechanics ◽  
Ground State ◽  
Experimental Testing ◽  
Power Level ◽  
Green Energy ◽  
Average Error ◽  
Paramagnetic Resonance ◽  
Continuous Power ◽  
Electron Paramagnetic

Abstract Quantum mechanics postulates that the hydrogen atom has a stable ground state from which it can be promoted to excited states by capture of electromagnetic radiation, with the energy of all possible states given by En = -13.598/n2 eV, in which n ≥ 1 is a positive integer. By contrast, it has been proposed that the n = 1 state is not the true ground state, and that so-called ‘hydrino’ states of lower energy can exist, which are characterized by fractional quantum numbers n = 1/p, in which 1 < p ≤ 137 is a limited integer1,2. Electron transition to a hydrino state, H(1/p) is non-radiative and requires a quantized amount of energy, 2mE1 (m is an integer), to be transferred to a catalyst3,4. Since its inception5 the hydrino hypothesis has remained highly controversial6-17 and laboratory verification studies by its proponents have been criticised18,19. Remarkably, no experimental testing by independent researchers has been described in the literature over the past 31 years. Here, we give an account of an independent electron paramagnetic resonance (EPR) study of molecular hydrino H2(1/4) that was produced by a plasma reaction of atomic hydrogen with non-hydrogen bonded water as the catalyst. A sharp, complex, multi-line EPR spectrum is found, whose detailed properties prove to be semi-quantitatively consistent with predictions20 from hydrino theory with an average error less than 0.09 G (0.2%) over a 39 G span of 37 lines. We have sought but failed to find reasonable alternative, ‘conventional’ interpretations for the detected paramagnetism. Fundamental relevance of the hydrino hypothesis lies in its challenging some of the foundations of the theory of quantum mechanics1. Very high net energy release during hydrino formation signifies technological relevance as a novel method of green energy production with recent validation at the 100 kW continuous power level by measurement of steam production20-27.

Rapid‐Scan Electron Paramagnetic Resonance of Highly Resolved Hyperfine Lines in Organic Radicals.

ChemPhysChem ◽  
2020 ◽  
Vol 21 (22) ◽  
pp. 2564-2570
Author(s):  
Joseph E. McPeak ◽  
Peter Höfer ◽  
Sylwia Kacprzak ◽  
Patrick Carl ◽  
Ralph Weber ◽  
...  
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Organic Radicals ◽  
Paramagnetic Resonance ◽  
Rapid Scan ◽  
Electron Paramagnetic

Applications of EPR Spectrometer in Environmental Samples

2015 ◽  
Vol 1092-1093 ◽  
pp. 589-592
Author(s):  
Shao Hua Liao ◽  
Fang Yang ◽  
Fang Fang Li ◽  
Jing Yang ◽  
Min Wu
Keyword(s):  
Carbon Nanotubes ◽  
Electron Paramagnetic Resonance ◽  
Free Radicals ◽  
Transition Metals ◽  
Environmental Samples ◽  
High Sensitivity ◽  
Organic Radicals ◽  
Paramagnetic Resonance ◽  
Potential Risks ◽  
Electron Paramagnetic

Electron paramagnetic resonance (EPR) spectrometer was widely applied to physics, chemistry and biomedicine. This research provided possible electron and valence information of environmental samples interaction through high sensitivity. The EPR signals of transition metals and organic radicals were distinguished well. Three kinds of carbon nanotubes (CNTs) (MW50, MW30 and MWG) had strong EPR signals. Addition of transition metals may be a suitable way to decrease environmentally persistent free radicals (EPFRs). The potential risks of EPFRs in BC and the reactive free electron in transition metals must be addressed to ensure their safe and scientific absorption application.

Electron Paramagnetic Resonance and Mass Spectroscopy Study of Spin-Trapped Radicals: Styrene—Amine Photoreactions

1997 ◽  
Vol 51 (6) ◽  
pp. 874-879 ◽  
Author(s):  
Chiou-Rong Lin ◽  
Kai Pan ◽  
Tong-Ing Ho
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Resolution Enhancement ◽  
Secondary Amines ◽  
Spectroscopy Study ◽  
Paramagnetic Resonance ◽  
Mass Spectral ◽  
Radical Intermediates ◽  
Substituent Constants ◽  
Electron Paramagnetic ◽  
Aminoxyl Radicals

The free radical intermediates from the photolysis of eleven substituted styrenes (1–11) with both tertiary and secondary amines were studied by spin trapping and the high-pressure liquid chromatography electron paramagnetic resonance (HPLC-EPR) technique. Eleven α-methylbenzyl radicals were trapped by 2-methyl-2-nitro-sopropane (MNP) and separated by HPLC. Resolution enhancement was applied to obtain long-range hyperfine splitting constants (hfsc). The nitrogen hfsc are linearly correlated with the Hammett substituent constants. The major mass spectral fragments for the trapped aminoxyl radicals (12–22) include [M+1]+, [M–1]+, [M– tBu]+, [M– tBuOH]+, [M– tBuNO]+, and [(CH3)3C]+. The structures of 12–22 were also confirmed by chemical synthesis by adding Grignard reagent to α-phenyl- N- tert-butylnitrone (PBN) and its derivatives.

scholarly journals Simulation of nitrogen nuclear spin magnetization of liquid solved nitroxides

2021 ◽  
Author(s):  
Andriy Marko ◽  
Antonín Sojka ◽  
Oleksii Laguta ◽  
Petr Neugebauer
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Unpaired Electron ◽  
Nuclear Spin ◽  
Organic Radicals ◽  
Nuclear Spins ◽  
Nitroxide Radicals ◽  
Paramagnetic Resonance ◽  
Spin Magnetization ◽  
Electron Paramagnetic

Nitroxide radicals are widely used in Electron Paramagnetic Resonance (EPR) applications. Nitroxides are stable organic radicals containing ${\rm N-O}^\bullet$ group with hyperfine coupled unpaired electron and nitrogen nuclear spins. In...

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