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Cadmium sulfide thin films were prepared by chemical bath on glass substrates at 80 °C. CdS was Er-doped during the growth process by adding water-diluted Er(NO3)33·H2O to the CdS aqueous growing solution. The relative volume of the doping solution was varied in order to obtain different doping levels. The crystalline structure of CdS:Er films was cubic zinc blende for all the doped layers prepared. The (111) interplanar distance has an irregular variation with the Er doping level. Consequently, the band gap energy (Eg) firstly increases and afterward diminishes becoming, at last, approximately constant at around Eg=2.37 eV. For higher doping levels, in the as-grown films, dark electrical conductivity (σ) values reach 1.8×10-2 Ω-1 cm-1 at room temperature. The logarithm of σ vs 1/kT plot, where k is Boltzmann’s constant and T the absolute temperature, indicates an effective doping of CdS as a result of the Er introduction into the lattice of the material. Hall effect measurements reveal a n-type doping with 2.8×1019 cm-3 as maximum carrier density. [ABSTRACT FROM AUTHOR]

We report on the results of electrical characterization experiments on metal/pentacene contacts. The metals explored were gold, silver, and platinum. Two kinds of devices were fabricated and tested: symmetric metal/pentacene/metal structures and nonsymmetric metal/pentacene/indium-tin-oxide structures. The rectification ratio of the latter devices was found to depend strongly on the metal and ranged between 2 and 103 for applied voltages of ±1 V. Schottky barrier heights were extracted from the reverse current activation energy measurements over the temperature range of ∼240–340 K. Numerical device modeling using the experimentally determined Schottky barrier heights yielded results that are consistent with the experimental current-voltage characteristics, and indicated the presence of a non-negligible (trapped) positive space charge in the pentacene films. [ABSTRACT FROM AUTHOR]

Studies the electrical switching properties of a polymer current limiter device as a function of applied voltage. Material and device configuration; High power switching results; Discussion.

Studies the reversible nonvolatile effects of electrical measurements of nitrogen doped tetrahedral amorphous carbon thin films. Methodology used in the experiment; Results and discussion; Conclusions.

This paper evaluates a needle-free injector using electrically induced bubbles. For a minimally invasive injector, the configuration of the bubble reservoir, which is at the tip space of the bubble injector, must be optimized because the invasiveness depends on the breakdown distance of the electrically induced bubble. [2017–0121] [ABSTRACT FROM PUBLISHER]

The measurement of the force acting between two parallel, current-carrying wires is known as Ampère’s experiment. A mechanical balance was historically employed to measure that force. We report a simple experiment based on an electronic precision balance that is useful in clearly showing students the existence of this interaction and how to measure it. The ampere (A) is one of the fundamental quantities of the international system of units, defined only on the basis of the force acting between a pair of parallel wires through which current is flowing. [ABSTRACT FROM AUTHOR]

I suggest in this article that Benjamin Franklin's electrical experiments were naturalistic and reactive towards providential theories of natural harmony and electricity provided by the English experimentalists Stephen Hales, William Watson and Benjamin Wilson. Conceptualizing nature as a divine balance, Franklin rejected English arguments for God's conservation of nature's harmony, suggesting instead that nature had within itself the ability to re-equilibrate when rendered unbalanced. Whilst Franklin's work reveals an experimentally defined fissure between providential and naturalistic views of matter and motion in the mid-eighteenth century, his subsequent reflections on the use of natural philosophy sheds light on the divergent trajectory of utility implicit in these differing views. Hales and Watson in particular believed that insight into nature's providential manifestations gave the natural philosopher a medically restorative role, aligning the power of nature with God's benevolent purpose to heal the infirm. For Franklin, humanity behaved like nature, moving only when necessary. Natural philosophy existed to help these needs, making new worlds that had no dependence on God. [ABSTRACT FROM PUBLISHER]

'Nudges' are being widely promoted to encourage energy conservation. We show that the popular electricity conservation 'nudge' of providing feedback to households on own and peers' home electricity usage in a home electricity report is two to four times more effective with political liberals than with conservatives. Political conservatives are more likely than liberals to opt out of receiving the home electricity report and to report disliking the report. Our results suggest that energy conservation nudges need to be targeted to be most effective. [ABSTRACT FROM AUTHOR]

Microbial Fuel Cell (MFC) based on the process of microbial dissimilatory sulfate-reduction, provides the possibility of generating electricity while removing sulfates from the electrolytic solution. A MFC was constructed using Cation Exchange Membrane type CMI-7000S and graphite electrodes without addition of any toxic mediators as electron acceptors in the anode chamber, partially filled with natural zeolite. In a series of investigations the influence of basic technological parameters on the generated voltage was established in open circuit (OCV) - temperature, pH, ratio COD/SO4 and aeration intensity in the cathodic zone. A multifactorial regression analysis based on the experimentally obtained data was made as the importance of each of the investigated factors was established. [ABSTRACT FROM AUTHOR]

In this research paper we are reporting how experiments on Rectifier are performed using the concept of virtual Intelligent SoftLab (VIS). Rectification is the conversion of alternating current (AC) to direct current (DC). This model explains you with the fundamentals of AC (alternating current) and DC (direct current) voltages using VIS model. The process of converting bi-directional AC Voltage into unidirectional DC is show graphically. Software for conducting the experimentations in Rectifier has been developed which helps students to perform and practice the experiments. A Rectifier experiments provides a pictorial method of design and evaluating experiments. A Rectifier constructed using the Virtual SoftLab and observed actual outputs. This will help students in understanding working of rectifiers. This model performs half wave and full wave rectification successfully. [ABSTRACT FROM AUTHOR]

The article focuses on the life and discoveries of philosopher Benjamin Franklin who made an impact on the natural and political world through science. It says that when Franklin was in his forties, he and three members of the Library Co. of Philadelphia took up their experimentation with electricity. Furthermore, it mentions that science gave Franklin the political power, in which he appointed to different positions in the government.

Abstract: In recent decades piezo- and pyroelectricity found application in yet another important field of research. A number of methods have been developed which employ these properties to investigate the micro- and macroscopic polarization of materials. Advances in piezo- and pyroelectric imaging enabled researchers to examine the polarization distribution of a sample with unprecedented detail. This review attempts to inform the general reader about some of those experimental techniques and their findings. [ABSTRACT FROM AUTHOR]

Abstract: An experimental study of kerosene–water upward two-phase flow in a vertical pipe was carried out using hot-film, dual optical and Pitot tube probes to measure the water, kerosene drops and mixture velocities. Experiments were conducted in a vertical pipe of 77.8 mm inner diameter at 4.2 m from the inlet (L/D=54). The tests were carried out for constant superficial water velocities of 0.29, 0.59 and 0.77 m/s (flow rates = 83, 167 and 220 l/min) and volume fractions of 4.2%, 9.2%, 18.6% and 28.2%. The Fluent 6.3.26 was used to model the single and two-phase flow and to reproduce the results for the experimental study. Two methods were used to evaluate the accuracy of the probes for the measurement of the velocities of water, drops and mixture for two-phase flow: (i) comparison of measured local velocities with predictions from the CFD simulation; (ii) comparison between the area-averaged velocities calculated from the integration of the local measurements of water, drops and mixture velocities and velocities calculated from flow meters’ measurements. The results for single phase flow measured using Pitot tube and hot-film probe agree well with CFD predictions. In the case of two-phase flow, the water and drops velocities were measured by hot-film and dual optical probes respectively. The latter was also used to measure the volume fraction. These three measured parameters were used to calculate the mixture velocity. The Pitot tube was also used to measure the mixture velocity by applying the same principle used for single phase flow velocity. Overall the mixture local velocity measured by Pitot tube and that calculated from hot-film and dual optical probe measurements agreed well with Fluent predictions. The discrepancy between the mixture area-averaged velocity and velocity calculated from flow meters was less than 10% except for one test case. It is concluded that the combined hot-film and optical approach can be used for water and drop velocity measurements with good accuracy for the flow conditions considered in this study. The Pitot tube can also be used for the measurement of mixture velocities for conditions of mixture velocities greater than 0.4 m/s. The small discrepancy between the predictions and experimental data from the present study and literature demonstrated that both instrumentation and CFD simulations have the potential for two-phase flow investigation and industrial applications. [Copyright &y& Elsevier]

Abstract: A method for air–water two-phase flow measurement is proposed using a Venturi meter combined with an Electrical Resistance Tomography (ERT) sensor. Firstly, the real-time flow pattern of the two-phase flow is identified using the ERT sensor. Secondly, the void fraction of the two-phase flow is calculated from the conductance values through a void fraction measurement model, developed using the LS-SVM regression method. Thirdly, the mass quality is determined from the void fraction through void fraction-quality correlation. And finally, the mass flowrate of the two-phase flow is calculated from the mass quality and the differential pressure across the Venturi meter. Experimental results demonstrate that the proposed method is effective for the measurement of the mass flowrate of air–water flow. The proposed method introduces the flow pattern information in the measurement process, which minimizes the influence of flow pattern on the conventional differential pressure based methods. In addition, the mass quality is calculated from the void fraction, so the difficulty to obtain the mass quality in conventional methods is also overcome. Meanwhile, the new method is capable for providing concurrent measurements of multiple parameters of the two-phase flow including void fraction, mass quality and mass flowrate as well as an indication of the flow pattern. [ABSTRACT FROM AUTHOR]

Abstract: Radial variation of the gas hold-ups and mean hold-ups are investigated in a 90 mm outer loop bubble column using electrical resistance tomography (ERT) with two axial locations (Plane 1 and Plane 2). In all the experiments, air is used as the gas phase, tap water as liquid phase, and polypropylene particles as solid phase where the superficial gas velocity is varied from 0.02 to 0.25 m/s. The effect of operating conditions, solid concentration on mean hold-ups and radial gas hold-ups distribution is discussed. Gas hold-ups and solid hold-ups results using ERT are in very good agreement with conventional estimation and correlations obtained using pressure transmitter methods. Meanwhile, the results show that the gas hold-ups in the centre region increase constantly with an increase in the superficial gas velocity, namely there is a maximum hold-up at the centre of cross-section. But, solid hold-ups distribution is very homogeneous for high gas velocity. According to the visible image, the gas–liquid flow behaviours are obtained for gas–liquid–solid outer loop bubble column. Furthermore, the results also indicate that ERT is a very powerful tool for diagnosing the ‘inside’ flow behaviour of gas–liquid–solid three phase bubble column. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, a combined model of computational fluid dynamics and the discrete element method (CFD–DEM) was used to simulate the particle distributions in a down-flow fluidized bed (DFB) with a newly designed particle–air distributor. In the simulation model, particle motion is calculated by solving Newton’s equations and the flow field of air is predicted by the Navier–Stokes equations. The calculation was made for the same geometric and operating conditions as the experiment which was carried out for comparison with the simulation using electrical capacitance tomography (ECT). The numerical predictions for the axial and radial profiles of the particle distribution agreed well with the experimental results. [ABSTRACT FROM AUTHOR]

Abstract: This paper covers the results of tests with the slender cylindrical silo emptied both gravitationally and in a controlled manner. The measurement technique chosen as an examination tool is the Electrical Capacitance Tomography (ECT). The major aim of this paper is to demonstrate the measurement capabilities of ECT system dedicated to detect oscillations in non-cohesive sand during silo flow. The actual experimental measurements were preceded by analysis of signal noise for static and dynamic tests. The influence of the initial density, wall roughness, elevation and velocity on the emptying process and vibrations is examined, as well. Results are presented in the form of continuous, concentration vs. time, graphs. Graphs are plotted on the basis of the raw measurement data and values of chosen reconstructed image pixels. [ABSTRACT FROM AUTHOR]

The article2 presents an introduction to research experiment carried out in the Science Teaching Methods course part of a Masters Degree program emphasizing teacher-researcher education. The experiment used a qualitative methodological approach, applied to Elementary and High Schools where participant observation technique was used during the experimental activities in the field of electricity. The results show how the education through research was experienced, which comprised activities in research project elaboration, data analyses and interpretation, and culminating with the collective elaboration of the present paper. The relevance given to this kind of education is noticeable, with promising consequences on teaching and research activities. In this process the importance of the pupils' background knowledge was taken into account, having in mind the improvement of the teacher/researcher pedagogical practice as well as pupil learning possibilities. [ABSTRACT FROM AUTHOR]

Alexander Garden (1730-1791) was born in Scotland, where he trained in medicine before settling in South Carolina in 1752. With a passion for collecting and a love of nature, he sent specimens to Linnaeus and his associates in Europe. In 1774, Garden observed and conducted electrical experiments on some "eels" that had survived the trip from Surinam to Charleston. His detailed observations and reasons for believing they emit electricity were read before the Royal Society of London and subsequently published. He also advised the sea captain who owned the eels on how to preserve them and where to deliver their bodies if they died en route to London. Although they did die en route, John Hunter of the Royal Society was able to provide excellent descriptions of their electric organs because they were so well preserved. The sequence of events that followed led to other live eels surviving the voyage to London, where they were observed to spark in darkness in 1776. This was a critical piece of evidence in favor of fish electricity and eventually for the more revolutionary idea that even human nerves and muscles might function electrically. [ABSTRACT FROM AUTHOR]

The ITER Organization (10) and the Institute of Plasma Physics at the Chinese Academy of Sciences (ASIPP) are jointly developing the 68 kA current leads using High Temperature Superconductors for the superconducting Toroidal Field (TF) magnet system of the International Thermonuclear Experimental Reactor, ITER. The proposed design consists of a conventional helium cooled heat exchanger operating between 65 K and 320 K and an HTS module covering the low temperature end using Bi-2223 tapes. The first HTS current lead prototypes will be tested in the EAST tokamak facility at ASIPP. This paper discusses the design of the first, 68 kA, TF HTS lead, which is the main emphasis of this first stage of the ITER current lead development program. [ABSTRACT FROM AUTHOR]

The production of electricity from ammonium was examined using a rotating-cathode microbial fuel cell (MFC). The addition of ammonium chloride, ammonium sulfate, or ammonium phosphate (monobasic) resulted in electricity generation, while adding sodium chloride, nitrate, or nitrite did not cause any increase in current production. The peak current increased with increasing amount of ammonium addition up to 62.3 mM of ammonium chloride, suggesting that ammonium was involved in electricity generation either directly as the anodic fuel or indirectly as substrates for nitrifiers to produce organic compounds for heterotrophs. Adding nitrate or nitrite with ammonium increased current production compared to solely ammonium addition. Using 16S rRNA-linked molecular analyses, we found ammonium-oxidizing bacteria and denitrifying bacteria on both the anode and cathode electrodes, whereas no anammox bacteria were detected. The dominant ammonium-oxidizing bacteria were closely related to Nitrosomonas europaea. The present MFC achieved an ammonium removal efficiency of 49.2 ± 5.9 or 69.1 ± 3.6%, depending on hydraulic retention time, but exhibited a very low Coulombic efficiency. [ABSTRACT FROM AUTHOR]

Synchronous Machine tests, such as no load, short circuit and zero power factor, are achieved to trace Zero Power-factor, Regulation and External Load characteristics, in addition to Voltage Regulation for any given state. To carry out this results we are familiarized with graphical methods, which are cumbersome and imprecise. This is a new cuasi analytic approach to this problem by means of a MATLAB software. Algorithm is similar to that followed by someone who is carrying out solutions by traditional way. It was implemented Magneto Motriz Force method. Saturation was approached to an inverse tangent curve in a least means square sense. To compute the interception point between curves it was used numerical methods which achieved a precision higher than experiments offer. This software is intended to be used either in Indutry or in universities with academic purpose. [ABSTRACT FROM AUTHOR]

The article offers information on the effect of embedded steel on electrical resistivity of concrete structures. It is mentioned that the electrical resistivity of the concrete is an important factor in determining the rate of corrosion. A test was conducted to determine the impact of embedded steel on electrical resistivity on concrete structures. The test was conducted in relation to four electrode testing of the electrical resistivity. Details related to the effects of cover thickness and curing conditions on the resistivity were also examined.

The decay time of residual DC charge in 500-kV transmission line was measured during five fine and dry days of winter. The results showed a large scattering not dependent on the simultaneously observed weather conditions, such as temperature or relative humidity. The authors performed an additional experiment in a laboratory to discuss the factors that affect the residual DC charge leakage in dry conditions focusing on the moisture in the air and the dust floating in the atmosphere. It is shown that absolute humidity alone decides the decay time without scattering under clean and calm condition. The floating dust blown up by the wind, however, reduces the decay time and brings a large scattering. The dust should be a charge carrier moving freely in the atmosphere. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(2): 45–52, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20417 [ABSTRACT FROM AUTHOR]

This paper presents experimental data that illustrates the intrinsic sensitivity of the thermoelectric contact technique based on the Seebeck effect, in order to detect the presence of anisotropy due to plastic deformation produced by the manufacturing process of cold working at different degrees of reduction in thickness, namely 40, 60 and 80% in Ti-6Al-4V. In addition to the morphological anisotropy, the Ti-6Al-4V alloy also exhibits a substantial thermoelectric anisotropy due to the preferred alignment of the predominantly hexagonal grain structure. The results describe the behaviour of the thermoelectric power (TEP) coefficient with respect to the anisotropy and microstructure in a highly textured material, that presents both morphological and crystallographic texture. Ultrasonic measurements of shear wave velocity were also conducted in order to obtain a direct correlation between the presence of a significant anisotropy in the cold-rolled Ti-6Al-4V samples and the TEP measurements, before and after heat treatment (annealing). TEP measurements offer a means to assess the evolution of the level of plastic deformation, which allows for a better correlation between texture-induced anisotropy and the material's microstructural and properties. Of course, the TEP values depend on the physical nature and degree of the imperfection that is to be characterized. [ABSTRACT FROM AUTHOR]

A study of the electrical losses of thin‐film modules is presented. Using the electrical circuit simulator PSpice, the influence of the distributed series resistance of the top and the bottom contact of the active area and the influence of the monolithic contact area on the module performance was revealed and demonstrated. A large impact of the distributed series resistance of transparent conducting oxide layer on the module performance was analysed. Study of the monolithic contact area shows a crucial impact of the back‐contact separation cut on the module performance. All other regions that form the monolithic contact contribute significantly to the width of the dead area region in a module. An application of the CIGS‐based study of the monolithic contact on an a‐Si/μc‐Si module is presented. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A low‐cost, non‐contact sensor that provides endpoint detectionfor each stage in a three‐stage CuInxGa1−xSe2 (CIGS( deposition is described. CIGS and precursoremissivity data providing the fundamental basis for the sensor's operation are presented. In situ operation of the sensor is outlined and sensor‐predicted film thickness, maximum Cu ratio during growth, as well as final Cu ratio are compared with those derived by other methods. Characteristics of the sensor relevant to automated and continuous processing are discussed. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Provides information on a study which focused on the influence of electrical coupling on early afterdepolarizations (EAD) propagation to normal neighboring tissue as ectopic beats. How the study was conducted; Effects of electrical coupling on EAD's formation; Influence of electrical coupling on EAD propagation; Conditions of simulations used in the study.

Studies the operation of the multipole single-phase switched reluctance generator (SRG) under faults. Characteristics of SRG; Description of output power under coil faults with constant currents; Investigation of the SRG under the faults.

Discusses the high-resistance power grounding of low-voltage (LV) systems used in petroleum and chemical industries. History of LV grounding; Observations from the review of ground-fault protection equipment; Design of a high-resistance grounded system; Applications for higher harmonic currents.

Describes an active gate drive circuit for series-connected insulated gate bipolar transistors (IGBT) with voltage balancing in high-voltage applications. Control for voltage balancing; Experimental framework of the study; Description of the experiments on voltage imbalances.

Deals with a study which presented a multi-agent model in conjunction with game theory to resolve the coalition formation for multilateral trades. Description of the coalition formation; Negotiation preference list; Introduction of the agent modelling techniques to simulate the dialogues and negotiation among market participants; Profit allocation.

Discusses the nineteenth century discoveries of the relationship between electricity and life. Details on speculations about the links between the forces of electricity, heat, light and magnetism; Information on experiments which seeks to prove the relationship; What was revealed.

History has not been kind to the Abbe Nollet. Greatly esteemed in his lifetime as the master of French experimental physics, and especially of the then new science of electricity, he is remembered today--when he is remembered at all--simply as a remarkably successful vulgarizer of science. Nollet, we recall, was the man who carried electrical demonstrating to the very pinnacle of French society, the court of Louis XV himself, and amused the King by causing a long line of monks to leap as one into the air when a battery of Leyden jars was discharged through them. But we tend to dismiss with, at best, a shrug and a knowing smile, his more serious efforts at constructing a theory of electricity adequate to account for the then known phenomena. His theory was from the outset, such gestures imply, both impossibly complex and hopelessly wrong, and it was a fortunate chance indeed that saw it overwhelmed within a few years of its first, being made public by Benjamin Franklin's vastly better alternative. [ABSTRACT FROM AUTHOR]

Focuses on the work of physicist Benjamin Franklin with electricity. Reputation that he derived; Examples of electrical demonstrations in the 1740s; Details of his experiment on the Leyden jar.

Part I. Proposes a model to describe all experimental results on electrical aging of cables. Discussion on predictions made by the model; Experiments done; Results of the experiments.

Presents information as it relates to the formulations in calculating electric fields. Method used in the formulation; Differences in solving a floating potential to one in single dielectric cases; Formula for a solid dielectric.

The article presents information on American inventor and statesmen Benjamin Franklin's experiments with electricity and lightning. The article explores letters written by Franklin in an effort to gain insight on the development of his ideas about the electrical nature of lightning. The letters include correspondences with other scientists including one that discusses his experiment conducted with the kite. The author discusses the date of this experiment and how scholars have written about this event when writing Franklin biographies.

The article looks at a study which examined the characteristics of pre-pain sensation in human teeth using electrical stimulation. The study also considered the reaction time and fusion time of pre-pain sensation, which the author describes as the weakest sensation elicited by electrical stimulation.

The author discusses a classroom science experiment for elementary children that asks them to light a light bulb using only wire and a battery, and describes students' frustrations with the formative assessment probe for studying electric circuits. The use of scientific equipment in classrooms is discussed, and the author suggests that teachers' observe students to gauge how the materials affect their conceptual learning.

Planar 4 H-SiC p-n junctions with floating guard rings have been fabricated. The main junction and the rings were formed by room temperature boron implantation followed by high temperature annealing. The breakdown voltage of the p-n junctions is 1800 V, which twice exceeds that of similar junctions without guard rings and reaches 72% of the calculated breakdown voltage of a plane-parallel p-n junction with the same epitaxial layer parameters [ABSTRACT FROM AUTHOR]

We discuss the new CLEO-c EventStore: a pluggable system that scales from personal needs up to collaboration-wide managed data. Its indexing and versioning features allow physicists to quickly access raw, reconstructed and MC data. It does simple bookkeeping of desired datasets and guarantees the reproducibility of various details of physics analysis. A wide range of physics queries and a variety of file formats are supported. [ABSTRACT FROM AUTHOR]

Describes an extension of the Capacitor-Aided System for Teaching and Learning Electricity (CASTLE) project curriculum materials by introducing hand generators. Inclusion of the analysis of electrical work and the effects of the magnetic fields in the CASTLE project; Experiments with the hand generators.