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In search of an optimal gene electrotransfer (GET) protocol, an electroporation-based (EP) tumor treatment with great potential as a non-viral gene-delivery system, the concept of the dose-response relationship is introduced. It is shown that a reliable dose parameter is the pulse dosage and reliable response parameters are the reversibly electroporated tissue area as well as the unwanted damaged tissue area and plasmid damage due to pH. The standard stationary EP model consists in computing the reversibly electroporated tissue area in the first pulse as the region of tissue subjected to an electric field distribution higher than an electric field threshold for EP, where the electric field threshold comes from an experimental measurement and the electric field distribution from the solution of the nonlinear stationary Laplace equation for the electrostatic potential. The extended standard EP model introduced here consists in replicating for n consecutive pulses the standard EP model, via the experimental measurement in time of the successive thresholds. Because experimental data of this threshold variation is lacking, an exponential time decay function is assumed based on experimental measurements. The damage induced by pH fronts is defined as the tissue area subjected to pH abrupt changes above a basic threshold or below an acid threshold, where these changes come from numerical solutions via the electrolytic ablation (EA) model for EP-based protocols and the basic and acid thresholds from experiments. An optimal dose-response relationship in a GET protocol, for the range of pulse intensities with fixed pulse length and frequency, tested here, is predicted as the critical pulse dosage yielding maximum reversibly electroporated tissue area with minimal tissue area damage induced by pH fronts. Moreover, since damage induced by pH changes is proportional to the Coulomb dosage, damage induced by pH fronts is negligible in typical EP-based tumor protocols such as in electrochemotherapy (ECT) and irreversible electroporation (IRE) but not in GET, due to the most often longer pulses applied/used, i.e. higher dosage applied. Image 1 • Pulse dosage is a reliable dose parameter in a GET protocol. • Reversibly electroporated tissue, and damaged tissue induced by pH fronts are reliable response parameters in a GET protocol. • Optimal dose-response in GET protocols is the critical pulse dose yielding maximum electroporated tissue with minimum damage. • pH damage is negligible in ECT and IRE, but not in GET, due to the most often higher dosage applied. [ABSTRACT FROM AUTHOR]

This paper deals with Potential Induced Degradation (PID) of p -type monocrystalline PV modules (Evergreen) from a photovoltaic power plant that has been in operation mode for 7 years. Within the PV module affected by the PID degradation, the effect of the electric field on individual PV cells is studied. The distribution of the electric field was simulated by SolidWorks software. The results show a random distribution of affected PV cells not related to the size and distribution of the electric field intensity. Furthermore, the dependencies of negative voltage potential on the range of PID degradation of individual PV modules located in the negative pole of the PV string is made. From measured current voltage characteristics (measured at STC), it is evident that the value of negative voltage potential is not directly proportional to the PID occurrence. These results are supplemented by electroluminescence images which confirm this finding. [ABSTRACT FROM AUTHOR]

A pole mounted 'field mill' type electrostatic fieldmeter provides a simple and practical way for measurement, and for long term continuous monitoring, of ground level atmospheric electric fields. The paper describes a number of studies of this measurement method. These show how atmospheric electric field values are derived from the response of the fieldmeter when earth bonded and its height above ground level. The response of the fieldmeter is calibrated via the linear variation of its response to voltage applied during the set up procedure. The studies confirm a linearity of fieldmeter response with height above ground. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present a numerical algorithm for investigating the dynamic characteristics of a simple model of the dielectric barrier discharge in air. The proposed algorithm is based on the finite element method and is capable of determining the distribution of electric field intensity and space charge density in the point-plane geometry, when the plane is covered with a thin dielectric layer and the needle is energized with a sinusoidal voltage. The simulation results show the behavior of corona current and space charge density for a few values of the input voltage and frequency. The aim of this parametric study is to investigate the effect of voltage, and frequency on the time variation of the discharge. [ABSTRACT FROM AUTHOR]

Highlights: [•] New method for charge mobility measurement in organic semiconductor thin films. [•] Measuring mobility as function of electric field and charge carrier density μ(F, n). [•] Direct measurement – no fitting to a mobility model required. [•] Based on space-charge limited current in single carrier devices of varying thickness. [•] Applicable to neat and blend layers. [Copyright &y& Elsevier]

Abstract: A calculation has been performed for the interaction force and the field strength in a system consisting of two charged conducting balls in three cases: 1) the balls are maintained at the preset potentials; 2) the balls are insulated and have fixed charges; 3) one of the balls has the preset potential, and the second one has the preset charge. Experimental measurements of forces in the first and third cases were performed and fair agreement with calculations was confirmed. A calculation method has been suggested, and the electric field strength on the nearest poles of the balls has been calculated for the three mentioned cases. A good agreement with the other authors' calculation results has been demonstrated. [Copyright &y& Elsevier]

The response of field mill type electrostatic fieldmeters to alternating electric fields is limited by the chopping frequency. Measurements reported here show that alternating frequencies at the chopping frequency, and related harmonics, can create confusing low frequency outputs. Hence care is needed for interpreting observations where such alternating electric fields may be present. [ABSTRACT FROM AUTHOR]

This communication uncovers missing fundamental elements and an expanded model of gas phase electrodeposition; a relatively new and in large parts unexplored process, which combines particle generation, transport zone and deposition zone in an interacting setup. The process enables selected area deposition of charged nanoparticles that are dispersed and transported by a carrier gas at atmospheric pressure conditions. Two key parameters have been identified: carrier gas flow rate and spark discharge power. Both parameters affect electrical current carried by charged species, nanoparticle mass, particle size and film morphology. In combination, these values enable to provide an estimate of the gas flow dependent Debye length. Together with Langmuir probe measurements of electric potential and field distribution, the transport can be described and understood. First, the transport of the charged species is dominated by the carrier gas flow. In close proximity, the transport is electric field driven. The transition region is not fixed and correlates with the electric potential profile, which is strongly dependent on the deposition rate. Considering the film morphology, the power of the discharge turns out to be the most relevant parameter. Low spark power combined with low gas flow leads to dendritic film growth. In contrast, higher spark power combined with higher gas flow produces compact layers. This contribution describes an extended model of the gas phase electrodeposition. For the first time correlations between the transport gas flow, the spark discharge power, the nanoparticle flow, the nanoparticle mass and the film morphology are shown. The transport properties in the gas phase are strongly dependent on the transport gas flow, which represents the biggest difference in the description of the transport equation compared to classic electroplating. Image 1 • This article reports materials, methods and technology to increase the understanding of the in large parts unexplored gas phase electrodeposition process. • To understand the expanded model, two key parameters have been identified; the carrier gas flow rate and the spark discharge plasma power. • Both parameters affect measurable quantities such as the electrical current carried by the charged nanoparticles and gas ions, the nanoparticle mass, particle size and film morphology. • Particle generation rate, ratio between charged gas ions and charged nanoparticles are subsequently derived. • Together with Langmuir probe measurements of the electric potential and field distribution the transport can be described and understood. [ABSTRACT FROM AUTHOR]

Electrical dispersion of a water-in-oil emulsion under an electric field has an inhibitory effect on the eletrocoalescence. To clarify the mechanism of droplet breakup at the microscopic level, molecular dynamics simulation was performed to study the deformation and breakup characteristics of a moving droplet at different field strengths. The results showed that interparticle spacings increased with the growth of the field strength, leading to significantly higher values of the electrostatic potential and van der Waals potential, and hence an increase of the deformation degree. There was a substantial rise in the non-bonded potential energy with a sharp fall in the overall velocity of the droplet when the electric field was higher than 2.1 V nm−1, causing the development of droplet breakup. Through hydrogen bond and hydration analysis, it was found that the hydrogen bond lifetime and ion distribution were responsible for the formation of different breakup patterns. These results demonstrated that droplet break-up is highly dependent on weak intermolecular interactions such as strong attraction. • Weak interactions are used to explain droplet breakup mechanism. • Strong attraction has a significant impact on droplet breakup. • Three different droplet breakup modes are investigated. • Ion distribution and hydrogen bond lifetime can influence the breakup modes. [ABSTRACT FROM AUTHOR]

The economy of transporting large amount of power over long distance makes high voltage transmission line an important component of the power system. Outdoor insulators provide electrical insulation as well as mechanical support between energized conductor and grounded parts of the tower. Its performance is closely related to the reliability of power delivery. Various parameters affect the insulator flashover performance, but the measurement and analysis of all those parameters would be a challenging and complex task during online inspection. The performance of the insulators is directly dependent on the electric field distribution inside and surrounding them. The aim of this work is to obtain the relationship between flashover voltage and electric field distribution. Accordingly, a novel electric field measurement technology, which was recently commercially available, was utilized in this paper to measure the electric field distribution around six different varieties of composite and ceramic insulators. The relationship between conductivity of the contamination layer and the environmental relative humidity was initially evaluated. Further, the patterns of the electric field distribution for clean, uniform and non-uniform contamination cases were studied and its relationship with the flashover voltages was explored. Electric field calculation with commercially available package was performed to validate the experimental results and extend the conclusion to higher voltage levels. [ABSTRACT FROM AUTHOR]

• Study on the electromagnetic field onboard to evaluate EMI in critical points. • The onboard acquisition systems are potentially affect by electromagnetic noise. • A preliminary electromagnetic screening is advisable to optimize the ship cabling. When performing oceanography measurements, it is critical to assess the presence of the noise sources that could affect the measured data and lead to wrong interpretation of the results. This paper report the result of an oceanography survey conducted by ISMAR-CNR, Naples, in the north-eastern marine sector of the Ischia Island and assess the influence of EMI on the measured results. The analyzed measurements of the Electric and Magnetic fields showed values of the E up to 0.82 V/m and of B up to 85 μT. By assuming a standard conductor, an inductance L up to 47 Ω on the cable corresponding to an induced electromotive force of 1184 mV was calculated. Also the experimental data show the EMI increase in site where the Pearson index correlation is higher. The results demonstrate that in an oceanographic survey planning, a preliminary electromagnetic screening is advisable to optimize the measurement setup. [ABSTRACT FROM AUTHOR]