Evaluation of Reactive Species Produced in Water by GlidArc Plasma

Microplastics (MPs) are distributed in a wide range of aquatic and terrestrial ecosystems throughout the planet. They are known to adsorb hazardous substances and can transfer them across the trophic web. To eliminate MPs pollution in an environmentally friendly process, we propose using a photocatalytic process that can easily be implemented in wastewater treatment plants (WWTPs). As photocatalysis involves the formation of reactive species such as holes (h+), electrons (e−), hydroxyl (OH●), and superoxide ion (O2●−) radicals, it is imperative to determine the role of those species in the degradation process to design an effective photocatalytic system. However, for MPs, this information is limited in the literature. Therefore, we present such reactive species’ role in the degradation of high-density polyethylene (HDPE) MPs using C,N-TiO2. Tert-butanol, isopropyl alcohol (IPA), Tiron, and Cu(NO3)2 were confirmed as adequate OH●, h+, O2●− and e− scavengers. These results revealed for the first time that the formation of free OH● through the pathways involving the photogenerated e− plays an essential role in the MPs’ degradation. Furthermore, the degradation behaviors observed when h+ and O2●− were removed from the reaction system suggest that these species can also perform the initiating step of degradation.

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Relevance of mitochondrial dysfunction during Sorafenib-induced cell death in liver cancer cells. Role of oxidative and nitrogen reactive species

Free Radical Biology and Medicine ◽

10.1016/j.freeradbiomed.2020.12.418 ◽

2021 ◽

Vol 165 ◽

pp. 54

Author(s):

Patricia de la Cruz-Ojeda ◽

M. Ángeles Rodríguez-Hernández ◽

Elena Navarro-Villarán ◽

Paloma Gallego ◽

Pavla Staňková ◽

...

Keyword(s):

Cell Death ◽

Liver Cancer ◽

Mitochondrial Dysfunction ◽

Cancer Cells ◽

Reactive Species ◽

Liver Cancer Cells ◽

Nitrogen Reactive Species

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Non-thermal pulsed plasma activated water: environmentally friendly way for efficient surface modification of semiconductor nanoparticles

Green Chemistry ◽

10.1039/d0gc02619k ◽

2021 ◽

Author(s):

Pavel Galář ◽

Josef Khun ◽

Anna Fučíková ◽

Kateřina Dohnalová ◽

Tomáš Popelář ◽

...

Keyword(s):

Surface Modification ◽

Free Surface ◽

Thermal Plasma ◽

Environmentally Friendly ◽

Semiconductor Nanoparticles ◽

Reactive Species ◽

Pulsed Plasma ◽

Non Thermal Plasma ◽

Plasma Activated Water

Non-thermal plasma activated water can be used for cheap, easy and chemicals-free surface modification of nanoparticles, with all the reactive species originating solely in air and water.

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Ketoprofen degradation by surface reactive species on TiO2, AgxOy/MoxOy/catalysts

Materials Letters ◽

10.1016/j.matlet.2021.129687 ◽

2021 ◽

pp. 129687

Author(s):

Andrés Suárez-Escobar ◽

Vicente Rodríguez-González ◽

Carlos Gallardo-Vega ◽

Edwin Sarria ◽

Lorena Clavijo

Keyword(s):

Reactive Species

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Structire, Properties, and Process Characteristics of Low-K Materials Prepared by PECVD

MRS Proceedings ◽

10.1557/proc-565-255 ◽

1999 ◽

Vol 565 ◽

Author(s):

Y. Shimogaki ◽

S. W. Lim ◽

E. G. Loh ◽

Y. Nakano ◽

K. Tada ◽

...

Keyword(s):

Growth Rate ◽

Dielectric Constant ◽

Gas Flow ◽

Structural Changes ◽

Silicon Oxide ◽

Reactive Species ◽

Low Dielectric Constant ◽

Low Dielectric ◽

Step Coverage ◽

Low K

AbstractLow dielectric constant F-doped silicon oxide films (SiO:F) can be prepared by adding fluorine source, like as CF4 to the conventional PECVD processes. We could obtain SiO:F films with dielectric constant as low as 2.6 from the reaction mixture of SiH4/N2 O/CF4. The structural changes of the oxides were sensitively detected by Raman spectroscopy. The three-fold ring and network structure of the silicon oxides were selectively decreased by adding fluorine into the film. These structural changes contribute to the decrease ionic polarization of the film, but it was not the major factor for the low dielectric constant. The addition of fluorine was very effective to eliminate the Si-OH in the film and the disappearance of the Si-OH was the key factor to obtain low dielectric constant. A kinetic analysis of the process was also performed to investigate the reaction mechanism. We focused on the effect of gas flow rate, i.e. the residence time of the precursors in the reactor, on growth rate and step coverage of SiO:F films. It revealed that there exists two species to form SiO:F films. One is the reactive species which contributes to increase the growth rate and the other one is the less reactive species which contributes to have uniform step coverage. The same approach was made on the PECVD process to produce low-k C:F films from C2F4, and we found ionic species is the main precursor to form C:F films.

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Reactive species driven oxidative modifications of peptides—Tracing physical plasma liquid chemistry

Journal of Applied Physics ◽

10.1063/5.0046685 ◽

2021 ◽

Vol 129 (19) ◽

pp. 193305

Author(s):

Sebastian Wenske ◽

Jan-Wilm Lackmann ◽

Larissa Milena Busch ◽

Sander Bekeschus ◽

Thomas von Woedtke ◽

...

Keyword(s):

Reactive Species ◽

Oxidative Modifications ◽

Physical Plasma

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Zn(ferulate)-LSH Systems as Multifunctional Filters

Molecules ◽

10.3390/molecules26082349 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2349

Author(s):

Gustavo Pereira Saito ◽

Ana Carolina Lanfredi Matsumoto ◽

Renata Pires Assis ◽

Iguatemy Lourenço Brunetti ◽

Marco Aurélio Cebim ◽

...

Keyword(s):

Structural Changes ◽

Reactive Species ◽

Layered Compounds ◽

Human Organism ◽

Metal Hydroxides ◽

Spectroscopic Analyses ◽

Carboxylate Groups ◽

Constant Ph ◽

Solar Radiation Exposure

Excessive UV solar radiation exposure causes human health risks; therefore, the study of multifunctional filters is important to skin UV protective ability and also to other beneficial activities to the human organism, such as reduction of reactive oxygen species (ROS) responsible for cellular damages. Potential multifunctional filters were obtained by intercalating of ferulate anions into layered simple metal hydroxides (LSH) through anion exchange and precipitation at constant pH methods. Ultrasound treatment was used in order to investigate the structural changes in LSH-ferulate materials. Structural and spectroscopic analyses show the formation of layered materials composed by a mixture of LSH intercalated with ferulate anions, where carboxylate groups of ferulate species interact with LSH layers. UV-VIS absorption spectra and in vitro SPF measurements indicate that LSH-ferulate systems have UV shielding capacity, mainly UVB protection. The results of reactive species assays show the ability of layered compounds in capture DPPH•, ABTS•+, ROO•, and HOCl/OCl− reactive species. LSH-ferulate materials exhibit antioxidant activity and singular optical properties that enable their use as multifunctional filters.

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Hydrogenation of CO2 Promoted by Silicon-Activated H2S: Origin and Implications

Molecules ◽

10.3390/molecules26010050 ◽

2020 ◽

Vol 26 (1) ◽

pp. 50

Author(s):

Xing Liu

Keyword(s):

Low Temperatures ◽

Underlying Mechanism ◽

Reactive Species ◽

Co2 Hydrogenation ◽

Usual Method ◽

Title Reaction ◽

Hydrogenation Of Co2 ◽

Hydrogenation Reactions

Unlike the usual method of COx (x = 1, 2) hydrogenation using H2 directly, H2S and HSiSH (silicon-activated H2S) were selected as alternative hydrogen sources in this study for the COx hydrogenation reactions. Our results suggest that it is kinetically infeasible for hydrogen in the form of H2S to transfer to COx at low temperatures. However, when HSiSH is employed instead, the title reaction can be achieved. For this approach, the activation of CO2 is initiated by its interaction with the HSiSH molecule, a reactive species with both a hydridic Hδ− and protonic Hδ+. These active hydrogens are responsible for the successive C-end and O-end activations of CO2 and hence the final product (HCOOH). This finding represents a good example of an indirect hydrogen source used in CO2 hydrogenation through reactivity tuned by silicon incorporation, and thus the underlying mechanism will be valuable for the design of similar reactions.

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