Electrode stimulation: Redox reactions induced by modulating the electrostatic potential in solution

2019 ◽  
Vol 325 ◽  
pp. 134957
Author(s):  
Qi Han ◽  
Nicholas S. Georgescu ◽  
John Gibbons ◽  
Daniel Scherson
1997 ◽  
Vol 161 ◽  
pp. 437-442
Author(s):  
Salvatore Di Bernardo ◽  
Romana Fato ◽  
Giorgio Lenaz

AbstractOne of the peculiar aspects of living systems is the production and conservation of energy. This aspect is provided by specialized organelles, such as the mitochondria and chloroplasts, in developed living organisms. In primordial systems lacking specialized enzymatic complexes the energy supply was probably bound to the generation and maintenance of an asymmetric distribution of charged molecules in compartmentalized systems. On the basis of experimental evidence, we suggest that lipophilic quinones were involved in the generation of this asymmetrical distribution of charges through vectorial redox reactions across lipid membranes.


2012 ◽  
Vol 132 (1) ◽  
pp. 95-100
Author(s):  
Hiroshi Morita ◽  
Ayumu Hatanaka ◽  
Toshiyuki Yokosuka ◽  
Yoshitaka Seki ◽  
Yoshiaki Tsumuraya ◽  
...  

2014 ◽  
Vol 5 (2) ◽  
pp. 778-789
Author(s):  
Hassan Nouri Al-Obaidi ◽  
Ali A. Rashead Al-Azawy

Current research presents a visual-computational tool to design and investigate round electrostatic lenses in sense of analysis procedure. The finite elements methods is adopted to find the electrostatic potential in the lens region. Laplace’s equation is first replaced by a certain functional which physically represent the electric energy stored in the electric field. This functional is then minimized at each mesh point with respect to the nearest eight ones. This minimization process is proved to be entirely equivalent to solving Laplace’s equation. The requirement that the functional being minimized is then yields a set of nine point equations which inter relate the potentials at adjacent mesh points. Finally this set of equations is solved to find the electrostatic potential at each mesh point in the region of the lens under consideration. The procedure steps mention above are coded to program written in visual basic. Hence an interface tool for analyzing and designing electrostatic lenses has been built up. Designing results proved that the introduced tools has an excellent outputs in comparison with the others written in not visual programming languages. Furthermore it easier for researchers and designer to use such a tool over their counterpart ones.


2018 ◽  
Author(s):  
Timothy Duignan ◽  
Marcel Baer ◽  
Christopher Mundy

<div> <p> </p><div> <div> <div> <p>The surface tension of dilute salt water is a fundamental property that is crucial to understanding the complexity of many aqueous phase processes. Small ions are known to be repelled from the air-water surface leading to an increase in the surface tension in accordance with the Gibbs adsorption isotherm. The Jones-Ray effect refers to the observation that at extremely low salt concentration the surface tension decreases in apparent contradiction with thermodynamics. Determining the mechanism that is responsible for this Jones-Ray effect is important for theoretically predicting the distribution of ions near surfaces. Here we show that this surface tension decrease can be explained by surfactant impurities in water that create a substantial negative electrostatic potential at the air-water interface. This potential strongly attracts positive cations in water to the interface lowering the surface tension and thus explaining the signature of the Jones-Ray effect. At higher salt concentrations, this electrostatic potential is screened by the added salt reducing the magnitude of this effect. The effect of surface curvature on this behavior is also examined and the implications for unexplained bubble phenomena is discussed. This work suggests that the purity standards for water may be inadequate and that the interactions between ions with background impurities are important to incorporate into our understanding of the driving forces that give rise to the speciation of ions at interfaces. </p> </div> </div> </div> </div>


Author(s):  
Jungil Mok ◽  
Byungki Kang ◽  
Daesun Kim ◽  
Hongsun Hwang ◽  
Sangjae Rhee ◽  
...  

Abstract Systematic retention failure related on the adjacent electrostatic potential is studied with sub 20nm DRAM. Unlike traditional retention failures which are caused by gate induced drain leakage or junction leakage, this failure is influenced by the combination of adjacent signal line and adjacent contact node voltage. As the critical dimension between adjacent active and the adjacent signal line and contact node is scaled down, the effect of electric field caused by adjacent node on storage node is increased gradually. In this paper, we will show that the relationship between the combination electric field of adjacent nodes and the data retention characteristics and we will demonstrate the mechanism based on the electrical analysis and 3D TCAD simulation simultaneously.


2021 ◽  
Vol 17 ◽  
Author(s):  
Nasrin Masnabadi

Abstract: Conformational behaviors of 2,5-dimethoxy-2,5-dimethyl-1,4-dithiane (compound 1) and 2,5-dimethyl-2,5-bis (methylthio)-1,4-dithiane (compound 2) investigated by computational methods including B3LYP/6-311+G** and M06-2X/6-311+G** levels of theory and NBO analysis. The stereoelectronic effect of axial, axial (ax, ax) and equatorial, equa-torial (eq, eq) conformations were studied using NBO analysis. Using NBO analysis, the values of the stereoelectronic effects were calculated through the energy of stability associated with the electron transfers of compounds 1 and 2. The results showed that the eq, eq conformations of the studied compounds were more stable than their corresponding ax, ax conformations, and LP2X→σS1-C2 and LP2S→σ*C2-X electron transfers play important roles in the conformational be-havior of the studied compounds. The main purpose of the present work was to study the effects of stereoelectronic inter-actions and steric on the conformational superiority of the di-methoxy (compound 1) and di-thiomethyl compounds (com-pound 2). Thus, the values of resonance stability energy, non-diagonal elements, and orbital populations were investigated. Also, active electrophilic and nucleophilic centers were identified using fronting orbitals analysis obtained by DFT methods. The electrostatic potential maps of the title compounds were investigated at the B3LYP/6-311+G* level of theory. All of the NMR parameters and geometrical properties of both compounds were determined in this study.


2020 ◽  
Vol 16 (3) ◽  
pp. 265-283
Author(s):  
Kyriaki Hatziagapiou ◽  
George I. Lambrou

Background: Reactive oxygen species and reactive nitrogen species, which are collectively called reactive oxygen nitrogen species, are inevitable by-products of cellular metabolic redox reactions, such as oxidative phosphorylation in the mitochondrial respiratory chain, phagocytosis, reactions of biotransformation of exogenous and endogenous substrata in endoplasmic reticulum, eicosanoid synthesis, and redox reactions in the presence of metal with variable valence. Among medicinal plants there is a growing interest in Crocus sativus L. It is a perennial, stemless herb, belonging to Iridaceae family, cultivated in various countries such as Greece, Italy, Spain, Israel, Morocco, Turkey, Iran, India, China, Egypt and Mexico. Objective: The present study aims to address the anti-toxicant role of Crocus sativus L. in the cases of toxin and drug toxification. Materials and Methods: An electronic literature search was conducted by the two authors from 1993 to August 2017. Original articles and systematic reviews (with or without meta-analysis), as well as case reports were selected. Titles and abstracts of papers were screened by a third reviewer to determine whether they met the eligibility criteria, and full texts of the selected articles were retrieved. Results: The authors focused on literature concerning the role of Crocus Sativus L. as an anti-toxicant agent. Literature review showed that Saffron is a potent anti-toxicant agent with a plethora of applications ranging from anti-oxidant properties, to chemotherapy protective effects. Conclusion: Literature findings represented in current review herald promising results for using Crocus Sativus L. and/or its active constituents as anti-toxicant, chemotherapy-induced protection and toxin protection.


Sign in / Sign up

Export Citation Format

Share Document