scholarly journals The Peculiarities of Charge Motion in the Molecular Polynucleotide Chains of Finite Length. The Rapid Formation of a Moving Polaron State

2018 ◽  
Vol 13 (2) ◽  
pp. 534-550 ◽  
Author(s):  
A.N. Korshunova ◽  
V.D. Lakhno
Keyword(s):  
Charge Transfer ◽  
Electric Field ◽  
Finite Length ◽  
Numerical Experiments ◽  
Initial Conditions ◽  
Initial Time ◽  
Initial Moment ◽  
Polaron State ◽  
Rapid Formation ◽  
Dna Chain

The numerical experiments which demonstrate the possibility of charge transfer in a homogeneous G/C DNA chain in the absence of an electric field have been carried out. As a model, which describes the dynamics of a DNA molecule, was considered the nonlinear Peyrard-Bishop-Dauxois-Holstein model. It is commonly supposed that the main electric current carrier in homogeneous synthetic polynucleotide chains is the polaron. We have previously studied the peculiarities of polaron motion in molecular polynucleotide chains of finite length. It was shown that a polaron placed at the initial moment of time not in the center of the chain acquires the ability to move in the absence of an electric field and in the absence of any additional excitations in the chain. The numerical experiments which demonstrate the possibility of polaron charge transfer in a homogeneous finite unclosed G/C DNA chain due to the interaction with localized excitations have been carried out in the absence of an electric field. In this study, at the initial moment of time, a polaron is not added to the chain, but a charge localized in the region of a certain number of neighboring sites displaced from the equilibrium positions. The motion of the charge in the chain is caused by choice of these specified initial conditions, which ensure the rapid formation of the polaron state and, as a consequence, charge transfer along the chain. For the assignment of the external nonlinear excitations, we used nonzero values of the displacements of particles and/or their velocities at the initial instant of time. Non-zero values of chain sites velocities at the initial time were used to stimulate the motion of the charge. It is shown that for the rapid formation of the polaron state, the initial conditions must correspond to the parameters of the polaron, which is formed in the chain under the chosen parameters. It is shown that, depending on the parameters of the chain and on the parameters of the selected initial conditions, the charge can be transferred along the chain over long distances.

The Peculiarities of Polaron Motion in the Molecular Polynucleotide Chains of Finite Length

2016 ◽  
Vol 11 (2) ◽  
pp. 141-158 ◽  
Author(s):  
А.Н. Коршунова ◽  
A.N. Korshunova
Keyword(s):  
Charge Transfer ◽  
Electric Field ◽  
Finite Length ◽  
Numerical Experiments ◽  
Initial Moment ◽  
Initial Form ◽  
Dna Molecule ◽  
Holstein Model ◽  
Dna Chain

The numerical experiments which demonstrate the possibility of polaron charge transfer in a homogeneous finite unclosed G/C DNA chain in the absence of an electric field and additional excitations have been carried out. As a model, which describes the dynamics of a DNA molecule, was considered the Peyrard-Bishop-Holstein model. It is shown that the polaron placed at the initial moment of time not in the center of the chain, acquires the ability to move. It is also shown that the velocity of the polaron movement in the chain depends on its initial form.

scholarly journals The Peculiarities of Polaron Motion in the Molecular Polynucleotide Chains of Finite Length In The Presence Of Localized Excitations in the Chain

2017 ◽  
Vol 12 (1) ◽  
pp. 204-223 ◽  
Author(s):  
А.Н. Коршунова ◽  
A.N. Korshunova
Keyword(s):  
Charge Transfer ◽  
Electric Field ◽  
Finite Length ◽  
Numerical Experiments ◽  
Dna Molecule ◽  
Holstein Model ◽  
Localized Excitations ◽  
Dna Chain

The numerical experiments which demonstrate the possibility of polaron charge transfer in a homogeneous finite unclosed G/C DNA chain due to the interaction with localized excitations have been carried out in the absence of an electric field. As a model, which describes the dynamics of a DNA molecule, was considered the Peyrard-Bishop-Holstein model. It is shown that, depending on the parameters of the selected initial excitations and on the parameters of the chain, the polaron can move over long distances (about a thousand sites). It is also shown that the ability of a polaron to move and the character of this movement significantly depend on the relative positions of the polaron and the selected localized excitations.

scholarly journals The VIT Transform Approach to Discrete-Time Signals and Linear Time-Varying Systems

Eng ◽  
2021 ◽  
Vol 2 (1) ◽  
pp. 99-125
Author(s):  
Edward W. Kamen
Keyword(s):  
Discrete Time ◽  
Initial Conditions ◽  
Linear Time ◽  
Order Term ◽  
Initial Time ◽  
Time Varying ◽  
Varying Coefficients ◽  
Time Signals ◽  
Time Varying Systems ◽  
Time Varying Coefficients

A transform approach based on a variable initial time (VIT) formulation is developed for discrete-time signals and linear time-varying discrete-time systems or digital filters. The VIT transform is a formal power series in z−1, which converts functions given by linear time-varying difference equations into left polynomial fractions with variable coefficients, and with initial conditions incorporated into the framework. It is shown that the transform satisfies a number of properties that are analogous to those of the ordinary z-transform, and that it is possible to do scaling of z−i by time functions, which results in left-fraction forms for the transform of a large class of functions including sinusoids with general time-varying amplitudes and frequencies. Using the extended right Euclidean algorithm in a skew polynomial ring with time-varying coefficients, it is shown that a sum of left polynomial fractions can be written as a single fraction, which results in linear time-varying recursions for the inverse transform of the combined fraction. The extraction of a first-order term from a given polynomial fraction is carried out in terms of the evaluation of zi at time functions. In the application to linear time-varying systems, it is proved that the VIT transform of the system output is equal to the product of the VIT transform of the input and the VIT transform of the unit-pulse response function. For systems given by a time-varying moving average or an autoregressive model, the transform framework is used to determine the steady-state output response resulting from various signal inputs such as the step and cosine functions.

scholarly journals An In-Situ Reaction Route to Molecular Level Dispersed Bisimide and ZnO Nanorod Hybrids with Efficient Photo-Induced Charge Transfer

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Chunzheng Lv ◽  
Lirong He ◽  
Jiahong Tang ◽  
Feng Yang ◽  
Chuhong Zhang
Keyword(s):  
Charge Transfer ◽  
Electric Field ◽  
Self Assembly ◽  
Molecular Level ◽  
Surface Photovoltage ◽  
Zno Nanorod ◽  
In Situ Reaction ◽  
Perylene Bisimide ◽  
Induced Charge

AbstractAs an important photoconductive hybrid material, perylene/ZnO has attracted tremendous attention for photovoltaic-related applications, but generally faces a great challenge to design molecular level dispersed perylenes/ZnO nanohybrids due to easy phase separation between perylenes and ZnO nanocrystals. In this work, we reported an in-situ reaction method to prepare molecular level dispersed H-aggregates of perylene bisimide/ZnO nanorod hybrids. Surface photovoltage and electric field-induced surface photovoltage spectrum show that the photovoltage intensities of nanorod hybrids increased dramatically for 100 times compared with that of pristine perylene bisimide. The enhancement of photovoltage intensities resulting from two aspects: (1) the photo-generated electrons transfer from perylene bisimide to ZnO nanorod due to the electric field formed on the interface of perylene bisimide/ZnO; (2) the H-aggregates of perylene bisimide in ZnO nanorod composites, which is beneficial for photo-generated charge separation and transportation. The introduction of ordered self-assembly thiol-functionalized perylene-3,4,9,10-tetracarboxylic diimide (T-PTCDI)/ ZnO nanorod composites induces a significant improvement in incident photo-to-electron conversion efficiency. This work provides a novel mentality to boost photo-induced charge transfer efficiency, which brings new inspiration for the preparation of the highly efficient solar cell.

scholarly journals Interfacial chemical bond and internal electric field modulated Z-scheme Sv-ZnIn2S4/MoSe2 photocatalyst for efficient hydrogen evolution

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Xuehua Wang ◽  
Xianghu Wang ◽  
Jianfeng Huang ◽  
Shaoxiang Li ◽  
Alan Meng ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Electric Field ◽  
Hydrogen Evolution ◽  
Density Functional ◽  
Monochromatic Light ◽  
Density Functional Theory Calculations ◽  
Internal Electric Field ◽  
Apparent Quantum Yield ◽  
Paramagnetic Resonance ◽  
High Hydrogen

AbstractConstruction of Z-scheme heterostructure is of great significance for realizing efficient photocatalytic water splitting. However, the conscious modulation of Z-scheme charge transfer is still a great challenge. Herein, interfacial Mo-S bond and internal electric field modulated Z-scheme heterostructure composed by sulfur vacancies-rich ZnIn2S4 and MoSe2 was rationally fabricated for efficient photocatalytic hydrogen evolution. Systematic investigations reveal that Mo-S bond and internal electric field induce the Z-scheme charge transfer mechanism as confirmed by the surface photovoltage spectra, DMPO spin-trapping electron paramagnetic resonance spectra and density functional theory calculations. Under the intense synergy among the Mo-S bond, internal electric field and S-vacancies, the optimized photocatalyst exhibits high hydrogen evolution rate of 63.21 mmol∙g−1·h−1 with an apparent quantum yield of 76.48% at 420 nm monochromatic light, which is about 18.8-fold of the pristine ZIS. This work affords a useful inspiration on consciously modulating Z-scheme charge transfer by atomic-level interface control and internal electric field to signally promote the photocatalytic performance.

scholarly journals Restraining Surface Charge Accumulation and Enhancing Surface Flashover Voltage through Dielectric Coating

Coatings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 750
Author(s):  
Jixing Sun ◽  
Sibo Song ◽  
Xiyu Li ◽  
Yunlong Lv ◽  
Jiayi Ren ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Electric Field ◽  
Electric Fields ◽  
Transition Process ◽  
Metallic Particle ◽  
Particle Charging ◽  
Insulating Surfaces ◽  
Surface Flashover ◽  
Charging Time ◽  
The Impact

A conductive metallic particle in a gas-insulated metal-enclosed system can charge through conduction or induction and move between electrodes or on insulating surfaces, which may lead to breakdown and flashover. The charge on the metallic particle and the charging time vary depending on the spatial electric field intensity, the particle shape, and the electrode surface coating. The charged metallic particle can move between the electrodes under the influence of the spatial electric field, and it can discharge and become electrically conductive when colliding with the electrodes, thus changing its charge. This process and its factors are mainly affected by the coating condition of the colliding electrode. In addition, the interface characteristics affect the particle when it is near the insulator. The charge transition process also changes due to the electric field strength and the particle charging state. This paper explores the impact of the coating material on particle charging characteristics, movement, and discharge. Particle charging, movement, and charge transfer in DC, AC, and superimposed electric fields are summarized. Furthermore, the effects of conductive particles on discharge characteristics are compared between coated and bare electrodes. The reviewed studies demonstrate that the coating can effectively reduce particle charge and thus the probability of discharge. The presented research results can provide theoretical support and data for studying charge transfer theory and design optimization in a gas-insulated system.

scholarly journals Toward an Understanding of Tropical Cyclone Formation with a Nonhydrostatic, Mesoscale-Convection-Resolving Model§

2013 ◽  
Vol 7 (1) ◽  
pp. 37-50
Author(s):  
Masanori Yamasaki
Keyword(s):  
Tropical Cyclone ◽  
Numerical Experiments ◽  
Vertical Shear ◽  
Initial Time ◽  
Convective System ◽  
Vortex Center ◽  
Moist Convection ◽  
Mesoscale Convection ◽  
Tropical Cyclone Formation ◽  
Convective Systems

This paper describes results from numerical experiments which have been made toward a better understanding of tropical cyclone formation. This study uses a nonhydrostatic version of the author’s mesoscale-convection-resolving model that was developed in the 1980s to improve paramerization schemes of moist convection. In this study the horizontal grid size is taken to be 20 km in an area of 6,000 km x 3,000 km, and a non-uniform coarse grid is used in two areas to its north and south. Results from two numerical experiments are presented; one (case 1) without any environmental flow, and the other (case 2) with an easterly flow without low-level vertical shear. Three circular buoyancy perturbations are placed in the west-east direction at the initial time. Convection is initiated in the imposed latently unstable (positive CAPE) area. In both cases, a vortex with a pressure low is formed, and two band-shaped convective systems are formed to the north and the south of the vortex center. The vortex and two convective systems are oriented in the westsouthwest – eastnortheast direction, and their horizontal scales are nearly 2,000 km. In case 1, the band-shaped convective system on the southern side is stronger, and winds are stronger just to its south. In contrast, in case 2, the northern convective system is stronger, and winds are stronger just to its north. Therefore, the distributions of the equivalent potential temperature in the boundary layer and latent instability (positive buoyancy of the rising air) are also quite different between cases 1 and 2. The TC formation processes in these different cases are discussed, with an emphasis on the importance of examining the time change of latent instability field.

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