Effect of a side reaction with small heat liberation on the critical thermal-explosion condition of the main self-catalyzed reaction

Avoiding faradaic side reactions during the operation of electrochemical devices is important to enhance the device stability, to achieve low power consumption, and to prevent the formation of reactive side‑products. This is particularly important for bioelectronic devices which are designed to operate in biological systems. While redox‑active materials based on conducting and semiconducting polymers represent an exciting class of materials for bioelectronic devices, they are susceptible to electrochemical side‑reactions with molecular oxygen during device operation. We show that this electrochemical side reaction yields hydrogen peroxide (H2O2), a reactive side‑product, which may be harmful to the local biological environment and may also accelerate device degradation. We report a design strategy for the development of redox-active organic semiconductors based on donor-acceptor copolymers that prevent the formation of H2O2 during device operation. This study elucidates the previously overlooked side-reactions between redox-active conjugated polymers and molecular oxygen in electrochemical devices for bioelectronics, which is critical for the operation of electrolyte‑gated devices in application-relevant environments.

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Oxidation scheme of symmetrically disulphonated naphthidines with cerium(IV) sulphate

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19810561 ◽

1981 ◽

Vol 46 (3) ◽

pp. 561-572 ◽

Cited By ~ 3

Author(s):

Karel Komers

Keyword(s):

Sulphuric Acid ◽

Rate Constants ◽

Oxidation Product ◽

Side Reaction ◽

Reaction Scheme ◽

Second Order ◽

Intermediate Products ◽

Stable Intermediate ◽

Starting Compound ◽

Oxidation Agent

The author derived theoretical dependences of preasymptotic slopes of the currentless E-t curves (potential of an indicator redox electrode against time) on the number of equivalents, n, of added oxidation agent, assuming a reaction scheme of two consecutive concurrent second-order reactions involving the formation of intermediate products ( a side reaction of the starting compound with the final oxidation product leading to an adduct, which undergoes consecutive bimolecular oxidations leading again to the final product). The dependences enable to determine the type of the relatively stable intermediate products and the ratios of the rate constants. The theory was applied to the oxidation of four symmetrically disulphonated naphthidines with cerium(IV) sulphate in aqueous sulphuric acid and the results were substantiated spectrophotometrically

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N,N-Bis(Hexyl α-d-Acetylmannosyl) Acrylamide

Molbank ◽

10.3390/m1255 ◽

2021 ◽

Vol 2021 (3) ◽

pp. M1255

Author(s):

Atsushi Miyagawa ◽

Shinya Ohno ◽

Hatsuo Yamamura

Keyword(s):

Mass Spectrometry ◽

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Magnetic Resonance Spectroscopy ◽

Nuclear Magnetic Resonance Spectroscopy ◽

Side Reaction ◽

Resonance Spectroscopy ◽

Biological Functions ◽

Unknown Compound ◽

Acrylamide Monomer

Glycosyl monomers for the assembly of multivalent ligands are typically synthesized using carbohydrates with biological functions and polymerizable functional groups such as acrylamide or styrene introduced into the carbohydrate aglycon, and monomers polymerized using a radical initiator. Herein, we report the acryloylation of 6-aminohexyl α-mannoside and its conversion into the glycosyl monomer bearing an acrylamide group. The general acryloylation procedure afforded the desired N-hexyl acetylmannosyl acrylamide monomer as well as an unexpected compound with a close Rf value. The compounds were separated and analyzed by nuclear magnetic resonance spectroscopy and mass spectrometry, which revealed the unknown compound to be the bivalent N,N-bis(hexyl α-d-acetylmannosyl) acrylamide monomer, which contains two hexyl mannose units and one acrylamide group. To the best of our knowledge, this side reaction has not previously been disclosed, and may be useful for the construction of multivalent sugar ligands.

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Experimental and Computational Analyses of the Oxidation Mechanism of the Poly(arylsilane) Family as the Side Reaction during the Baking Process

The Journal of Physical Chemistry C ◽

10.1021/acs.jpcc.0c02416 ◽

2020 ◽

Vol 124 (29) ◽

pp. 16149-16158

Author(s):

Osamu Kobayashi ◽

Kunihiro Noda ◽

Naohiko Ikuma ◽

Dai Shiota ◽

Takayoshi Ishimoto ◽

...

Keyword(s):

Oxidation Mechanism ◽

Side Reaction ◽

Baking Process ◽

Computational Analyses

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Improvement of long-term cycling performance of high-nickel cathode materials by ZnO coating

Nanotechnology Reviews ◽

10.1515/ntrev-2021-0020 ◽

2021 ◽

Vol 10 (1) ◽

pp. 210-220

Author(s):

Fangfang Wang ◽

Ruoyu Hong ◽

Xuesong Lu ◽

Huiyong Liu ◽

Yuan Zhu ◽

...

Keyword(s):

Electrochemical Performance ◽

Lithium Ion Batteries ◽

Solid Phase ◽

Low Cost ◽

Specific Capacity ◽

High Capacity ◽

Lithium Ion ◽

Side Reaction ◽

Chemical Route ◽

High Nickel

Abstract The high-nickel cathode material of LiNi0.8Co0.15Al0.05O2 (LNCA) has a prospective application for lithium-ion batteries due to the high capacity and low cost. However, the side reaction between the electrolyte and the electrode seriously affects the cycling stability of lithium-ion batteries. In this work, Ni2+ preoxidation and the optimization of calcination temperature were carried out to reduce the cation mixing of LNCA, and solid-phase Al-doping improved the uniformity of element distribution and the orderliness of the layered structure. In addition, the surface of LNCA was homogeneously modified with ZnO coating by a facile wet-chemical route. Compared to the pristine LNCA, the optimized ZnO-coated LNCA showed excellent electrochemical performance with the first discharge-specific capacity of 187.5 mA h g−1, and the capacity retention of 91.3% at 0.2C after 100 cycles. The experiment demonstrated that the improved electrochemical performance of ZnO-coated LNCA is assigned to the surface coating of ZnO which protects LNCA from being corroded by the electrolyte during cycling.

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A Novel Stoichio-Kinetic Model for the DPPH• Assay: The Importance of the Side Reaction and Application to Complex Mixtures

Antioxidants ◽

10.3390/antiox10071019 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1019

Author(s):

Lucrezia Angeli ◽

Sebastian Imperiale ◽

Yubin Ding ◽

Matteo Scampicchio ◽

Ksenia Morozova

Keyword(s):

Antioxidant Activity ◽

Kinetic Model ◽

Rate Constant ◽

High Resolution Mass Spectrometry ◽

Sinapic Acid ◽

Side Reaction ◽

Main Reaction ◽

Dpph Assay ◽

Best Fitting ◽

The Common

The 2,2-diphenyl-1-picrylhydrazyl (DPPH•) assay is widely used to determine the antioxidant activity of food products and extracts. However, the common DPPH• protocol uses a two-point measurement and does not give information about the kinetics of the reaction. A novel stoichio-kinetic model applied in this study monitors the consumption of DPPH• by common antioxidants following the second order reaction. The fitting of such decay yields the rate constant k1, which describes the main reaction between antioxidants and DPPH•, and the rate constant k2, which is attributed to a slower side reaction considering the products generated between the transient radicals (AO•) and another molecule of DPPH•. The model was first applied to antioxidant standards. Sinapic acid, Trolox and ascorbic and chlorogenic acids did not show any side reaction. Instead gallic, ferulic and caffeic acids achieved the best fitting with k2. The products of the side reaction for these compounds were confirmed and identified with high-resolution mass spectrometry. Finally, the kinetic model was applied to evaluate the antioxidant activity of eight herbal extracts. This study suggests a new kinetic approach to standardize the common DPPH• assay for the determination of antioxidant activity.

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Modeling and Analysis of Compressive Properties of Porous NiTi Shape Memory Alloy Using Artificial Neural Network

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.41-42.135 ◽

2008 ◽

Vol 41-42 ◽

pp. 135-140 ◽

Cited By ~ 1

Author(s):

Qiang Li ◽

Xu Dong Sun ◽

Jing Yuan Yu ◽

Zhi Gang Liu ◽

Kai Duan

Keyword(s):

Neural Network ◽

Artificial Neural Network ◽

Shape Memory Alloy ◽

Shape Memory ◽

Thermal Explosion ◽

Process Parameters ◽

Niti Shape Memory Alloy ◽

Compressive Properties ◽

Porous Niti ◽

Bp Model

Artificial neural network (ANN) is an intriguing data processing technique. Over the last decade, it was applied widely in the chemistry field, but there were few applications in the porous NiTi shape memory alloy (SMA). In this paper, 32 sets of samples from thermal explosion experiments were used to build a three-layer BP (back propagation) neural network model. According to the registered BP model, the effect of process parameters including heating rate ( ), green density ( ) and particle size of Ti ( d ) on compressive properties of reacted products including ultimate compressive strength ( v D σ ) and ultimate compressive strain (ε ) was analyzed. The predicted results agree with the actual data within reasonable experimental error, which shows that the BP model is a practically very useful tool in the properties analysis and process parameters design of the porous NiTi SMA prepared by thermal explosion method.

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