The first ESR observation of radical species generated under pulsed electric fields processing

Zhang, Sha; Yang, Ruijin; Zhao, Wei; Liang, Qi; Zhong, Zhijun

doi:10.1016/j.lwt.2010.11.016

Cited by 40 publications

(20 citation statements)

References 13 publications

(14 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…4b). In addition, the hyperfine coupling constants (hfcc) for nitrogen (a N ) and hydrogen (a H ) atoms are shown in Table 1, and the hfcc values are well consistent with reported values, further confirming the formation of •H radical 54,55 . Moreover, the •H radical signal strengths of the samples were also compared (the peak area in Table 1).…”

Section: Mechanism Investigation Of Molecular Hydrogen Generationsupporting

confidence: 84%

Proton-assisted electron transfer and hydrogen-atom diffusion in a model system for photocatalytic hydrogen production

Zhang

Dai

et al. 2020

Commun Mater

View full text Add to dashboard Cite

Solar energy can be converted into chemical energy by photocatalytic water splitting to produce molecular hydrogen. Details of the photo-induced reaction mechanism occurring on the surface of a semiconductor are not fully understood, however. Herein, we employ a model photocatalytic system consisting of single atoms deposited on quantum dots that are anchored on to a primary photocatalyst to explore fundamental aspects of photolytic hydrogen generation. Single platinum atoms (Pt1) are anchored onto carbon nitride quantum dots (CNQDs), which are loaded onto graphitic carbon nitride nanosheets (CNS), forming a Pt1@CNQDs/CNS composite. Pt1@CNQDs/CNS provides a well-defined photocatalytic system in which the electron and proton transfer processes that lead to the formation of hydrogen gas can be investigated. Results suggest that hydrogen bonding between hydrophilic surface groups of the CNQDs and interfacial water molecules facilitates both proton-assisted electron transfer and sorption/desorption pathways. Surface bound hydrogen atoms appear to diffuse from CNQDs surface sites to the deposited Pt1 catalytic sites leading to higher hydrogen-atom fugacity surrounding each isolated Pt1 site. We identify a pathway that allows for hydrogen-atom recombination into molecular hydrogen and eventually to hydrogen bubble evolution.

show abstract

Section: Mechanism Investigation Of Molecular Hydrogen Generationsupporting

confidence: 84%

Proton-assisted electron transfer and hydrogen-atom diffusion in a model system for photocatalytic hydrogen production

Zhang

Dai

et al. 2020

Commun Mater

View full text Add to dashboard Cite

show abstract

“…The presence of polar groups can react with the interior macromolecules or active ingredients. Zhang et al [ 30 ] reported that the PEF processing generated hydrogen radicals in phosphate buffer and oleic acid emulsion, they also illustrated that the electric field strength had a significant effect on H 2 O 2 concentrations ( p < 0.5) when estimated using electron spin resonance (ESR) techniques. Thus, it was believed that the free radicals generated by PEF treatment attacked the hydroxyl, which belonged to the VIT-C second carbon atom to complete the conversion of configuration.…”

Section: Resultsmentioning

confidence: 99%

Effects of Pulsed Electric Fields (PEF) on Vitamin C and Its Antioxidant Properties

Zhang

Zeng

Brennan

et al. 2015

IJMS

View full text Add to dashboard Cite

In this study, pulsed electric fields (PEF) treatments and their effects on the structure of vitamin C (VIT-C) were estimated by fluorescence and Fourier transform infrared (FT-IR) spectroscopy, the relative content of VIT-C was measured by HPLC and the antioxidant properties of treated VIT-C by DPPH radical scavenging as well as reducing power tests. The fluorescence intensity of treated VIT-C increased slightly compared to the untreated VIT-C. Moreover, the effect of PEF on the structure of VIT-C was observed using the FT-IR spectra. These phenomena indicated that the PEF affected the conformation of VIT-C, which promoted the VIT-C isomer transformed enol-form into keto-form. In addition, the PEF treatments did not suffer the damage to VIT-C and could slow down the oxidation process in involving of experimental conditions by HPLC. The antioxidant properties of the treated VIT-C were enhanced, which was proved by radical scavenging and also the reducing power tests.

show abstract

“…The concentration of 2, 5-DHBA was greater after PEF processing with 0.2 μs-PRT, suggesting more free OH• radicals were generated by treatment with shorter PRT. The formation of free OH• radicals in PEF processing was previously reported (Raso & Heinz, 2006;Sun et al, 2011;Zhang, Yang, Zhao, Liang, & Zhang, 2011). The formation might be caused by severe electrochemical reactions that occurred at the electrodes in PEF system, which dissolution of metal ion, and the formation of highly reactive oxygen species (ROS), such as free OH• radicals and H 2 O 2 (Raso & Heinz, 2006).…”

Section: The Formation Of Free Oh• Radicals In Pef Processingmentioning

confidence: 86%

Effects of electric field strength and pulse rise time on physicochemical and sensory properties of apple juice by pulsed electric field

Liu

Rao

et al. 2013

Innovative Food Science & Emerging Technologies

View full text Add to dashboard Cite

The first ESR observation of radical species generated under pulsed electric fields processing

Cited by 40 publications

References 13 publications

Proton-assisted electron transfer and hydrogen-atom diffusion in a model system for photocatalytic hydrogen production

Proton-assisted electron transfer and hydrogen-atom diffusion in a model system for photocatalytic hydrogen production

Effects of Pulsed Electric Fields (PEF) on Vitamin C and Its Antioxidant Properties

Effects of electric field strength and pulse rise time on physicochemical and sensory properties of apple juice by pulsed electric field

Contact Info

Product

Resources

About