... SUPERCONDUCTORS, *ELECTRIC FIELDS, *ALTERNATING CURRENT ... SURFACE PROPERTIES, THINNESS, SCALAR FUNCTIONS, LOSSES ...

... FOR Transportable and Hybrid Transportable AC Systems Submitted 11 July, 2005 BY ... FOR Transportable and Hybrid Transportable AC Systems ...

Interstrand coupling losses are mainly due to currents perpendicular to the strands. A numerical model for calculating the current distribution of a single strand carrying a transverse transport current is presented. Also the effective resistance felt by the transport ...

AC losses in a superconductor strip are numerically evaluated by means of a finite element method formulated with a current vector potential. The expressions of AC losses in an infinite slab that corresponds to a simple model of infinitely stacked strips are also derived theoretically. It is assumed that the ...

The purpose of the study reported here was to examine generic cost differences between direct current (dc) and alternating current (ac) systems and to identify situations in which dc is clearly advantageous for long distance and bulk power transport. The ...

Low-temperature and high-temperature superconductors are used in liquid helium (LHe) as magnets and in other applications. AC transport current loss study is important for the use of these superconductors in alternating current regimes. The measurement of AC transport ...

The frequency-dependent critical current of a superconductor strip and Roebel cable has been studied using a 2D finite element simulation. It is shown that the critical current of the superconductor increases with frequency as f1/n, where n is the exponent of the power law flux creep model. Transport ac loss in a ...

A quasi-steady-state alternating current (ac) plasma operation was achieved successfully on the HT-7 superconducting tokamak. It is found in ac plasmas that the particle confinement time of positive current plasma (?p ~ 17 ms) is lower than that of negative current (?p ~ 31 ms) plasma. ...

In order to predict heat loads in future saturable core fault-current-limiting devices due to ac fringing fields, dynamic resistance in YBCO-coated conductors was measured at 77 K in peak ac fields up to 25 mT at 60 Hz and in dc fields up to 1 T. With the sample orientation set such that the conductor face was either parallel or ...

... low-tem- perature superconductors where crystal ... necessarily true for high-temperature super- conductors. ... temper- ature superconductor in regard ...

Many high-Tc superconducting (HTS) tape manufactures make an effort to improve the transport characteristics of HTS tapes. When AC or DC current flows in the HTS tape, AC or DC magnetic self-fields are induced around the conductor by the current and these self-fields affect on the ...

A.c. losses caused by an a.c. transport current and a transverse a.c. magnetic field during simultaneous action were measured. The loss contributions have been obtained separately. The measurements were performed on a NbTi multifilamentary wire having a CuNi matrix of low conductivity in order ...

This paper reports on the AC losses of internal-tin Nb{sub 3}Sn wires measured by an isothermal calorimetric method in triangular-wave fields at ramp rates up to 1.2 T/sec and in small-amplitude ripple fields biased with dc fields up to 9 T. Measurements were made both with and without transport currents, which were both ...

Although much research has been conducted concerning the losses of high-(Tc) superconductors, very little has concentrated on the self-field losses in an actual magnet arrangement. The coils studied in this work were designed for use as actual magnets in ...

This paper described the application of an AC surface probe, similar to presently used eddy current probes, to the measurement of DC transport critical currents and critical state dissipation in high {Tc} superconductors. It has been shown that the probe can provide quantitative measurement of the full field ...

This paper described the application of an AC surface probe, similar to presently used eddy current probes, to the measurement of DC transport critical currents and critical state dissipation in high [Tc] superconductors. It has been shown that the probe can provide quantitative measurement of the full field ...

Although much research has been conducted concerning the losses of high-{Tc} superconductors, very little has concentrated on the self-field losses in an actual magnet arrangement. The coils studied in this work were designed for use as actual magnets in an industrial application. Self field loss measurements were made upon tape-wound 2223 superconducting helix coils. The self-field losses were ...

Critical currents and AC losses of (Bi, Pb)2Sr2Ca2Cu3Ox superconducting tapes were measured in self-field as a function of temperature. The experimental data of the temperature dependence of critical current were compared with calculated results. An approach to calculating AC losses as a function of temperature was ...

PurposeAs a continuing effort to understand the mechanisms of alternating current (AC) transdermal iontophoresis and the iontophoretic transport pathways in the stratum corneum (SC), the objectives of the present study were to determine the interplay of AC frequency, AC voltage, and ...

Alternative current magnetoresistance (AC MR) method was applied to Si MOSFETs and AlGaN/GaN HEMTs at 4.2 K and 300 K. We show that the AC MR method allows to locally determine the quantum and transport relaxation times under the gate of micrometer and submicometer transistors.

The distribution of the Hall voltage induced by low-frequency AC current is studied theoretically in the incoherent linear transport of quantum Hall systems. It is shown that the Hall-voltage distribution makes a crossover from the uniform distribution to a concentrated-near-edges distribution as the frequency is increased or the ...

/18/05 AIChE/ACS New Haven 12 Paradigm Breaker: Microreaction Mass-Transport Limited Highly Exothermic Volumes, Quenching #12;20 10/18/05 AIChE/ACS New Haven 13 Barriers to Microreaction Philosophical Technical: Portable H2 Generation � Pharmaceutical Manufacturing: Background � Microreaction for Pharmaceutical

A quasi-stationary alternating current (AC) operation assisted by lower hybrid waves (LHW) was achieved recently in HT-7. It is found that the particle confinement time of the positive current plasma is lower than that of the negative current plasma. The particle transport coefficients are ...

The novel effects resulting from the entrainment of low mobility ions during alternating current (ac) electrospray ionization are examined through mass spectrometry and voltage/current measurements. Curious phenomena such as pH modulation at high frequencies (>150 kHz) of an applied ac electric field are ...

The authors measured AC losses of AC multifilamentary wires (NbTi and Nb{sub 3}Sn) and a cable of (6+1) configuration due to transport currents in an AC external magnetic field at 50Hz. They also studied the stabilities of the NbTi and Nb{sub 3}Sn wires and the cable. The Nb{sub 3}Sn ...

This book contains chapters on: the current-carrying mixed state at low and high fields; flux pinning and critical current density; current transport in a longitudinal applied magnetic field; flux in motion under the influence of a transport current; small-coil testing; ...

... 123. Percent Complete by Mode of Transportation (ACS). Overview ... Percent Complete by Mode of Transportation (ACS). -. -. Links on this page: Page ...

This paper presents a model to describe alternating current (AC) conductivity of DNA sequences, in which DNA is considered as a one-dimensional (1D) disordered system, and electrons transport via hopping between localized states. It finds that AC conductivity in DNA sequences increases as the frequency of the ...

The particle transport coefficients were investigated in ac plasmas by density modulation method on HT-7 tokamak. It is observed that the particle diffusion coefficient (D) is almost the same in various cases and varies with the electron density. The convection velocity (V) is equal to the value of inward pinch velocity (V) for low and high density ...

A novel method for AC loss measurement of a long length high Tc superconducting (HTSC) wire has been investigated. An 8 m long (Bi,Pb)2Sr2Ca2Cu3O10+x Ag clad multifilament wire was selected to prepare a special sample in which the inductive voltage induced by AC transport currents can be cancelled. Consequently the ...

This paper describes measured AC losses of NbTi Rutherford type cable when the wide side of the cable is parallel to the field variation. In the case of a Rutherford type cable, the orientation of the cable in the magnetic field is an important factor for the interstrand coupling loss which can be dominant over other AC losses such as hysteresis loss or ...

We propose and study a novel way to produce a dc transport of vortices when applying an ac electrical current to a sample. Specifically, we study superconductors with a graduated random pinning density, which transports interacting vortices as a ratchet system. We show that a ratchet effect appears as a consequence ...

Alternating current (AC) electrokinetic motion of colloidal particles suspended in an aqueous medium and subjected to a spatially nonuniform AC electric field are examined using a simple theoretical model that considers the relative magnitudes of dielectrophoresis, electrophoresis, AC-electroosmosis, and Brownian ...

A previous in vitro constant electrical resistance alternating current (AC) iontophoresis study with human epidermal membrane (HEM) and a model neutral permeant has shown less inter- and intra-sample variability in iontophoretic transport relative to conventional constant direct current (DC) iontophoresis. The ...

We describe a method to determine whether a measured current in a break junction is due to electron tunneling via space or conduction through a molecule bridged between two electrodes. By modulating the electrode separation, we monitor both the DC and the AC components of the current. The AC component indicates if ...

Alternating current (ac) electrokinetic motion of colloidal particles suspended in an aqueous medium and subjected to a spatially nonuniform ac electric field are examined using a simple theoretical model that considers the relative magnitudes of dielectrophoresis, electrophoresis, ac-electroosmosis, and Brownian ...

The vertical transport properties of ac-driven weakly-coupled superlattices have been investigated experimentally in this thesis. These include the frequency-locking phenomena, the ac-induced generation and annihilation of self-sustained current oscillations (SSCOs), and the appearance of ...

... IS BASED ON AN AC METHOD KNOWN IN ... WHEN AC CURRENT FLOWS THROUGH THE SYSTEM, IT ... LAYER AND AN IMPEDANCE OF THE ...

... The primary benefits of a TACS or HTACS system for the Military ... basis for larger scale implementation of with solar powered tactical AC systems. ...

AC loss can be a significant problem for any applications that utilize or produce an AC current or magnetic field, such as an electric machine. The authors investigate the electromagnetic properties of high temperature superconductors with a particular focus on the AC loss in superconducting coils made from YBCO ...

Recent results are reported pertaining to research of ac losses in superconductors with regard to magnet technology. Emphasis is on aspects which are important in demonstrating the technical feasibility and economical advantages of ac superconducting windings. In the domain of hysteresis losses the paper reports the extension of the theory of losses in a ...

... direct current into the ground via two electrodes. Resistivity surveys give an image of the subsurface resistivity distribution. ... particulate transport. enlarge figure Figure 4 (a�c) Resistivity tomogr...

The current distribution and also AC losses, in a multifilamentary superconductor carrying a transport current, are influenced by the self and the external magnetic field. By using the Maxwell equations, a model has been developed in order to calculate the temporal evolution of current ...

Multifilamentary Bi2223 tapes are exposed to the longitudinal magnetic field as well as the transverse one in some electrical power apparatuses such as multilayer power transmission cables. Here, we define the longitudinal and transverse magnetic fields as the field components parallel and perpendicular to the tape axis, respectively. If the filament-bundle is twisted, it can couple to the ...

We obtain exact results for the transport through a resonant level model (noninteracting Anderson impurity model) for rectangular voltage bias as a function of time. We study both the transient behavior after switching on the tunneling at time t = 0 and the ensuing steady state behavior. Explicit expressions are obtained for the ac ...

The scattering-matrix approach to phase-coherent transport is generalized to nonlinear ac transport. In photon-assisted electron transport it is often only the dc component of the current that is of experimental interest. But ac currents at all ...

Hysteretic ac losses in a thin, current-carrying superconductor strip located between two flat magnetic shields of infinite permeability are calculated using Bean's model of the critical state. Exact numerical calculations and approximate analytical forms delineating the penetration of magnetic flux and the energy dissipated during a cycle of the ...

... Title : CURRENT RATING OF AIRCRAFT CABLES FOR AC SYSTEMS,. Corporate Author : NAVAL RESEARCH LAB WASHINGTON DC. ...

In order to research the AC loss characteristics of a multi-layered conductor and a shield in a high temperature superconductor (HTS) cable, we prepared two short cable samples, which are the same as the 22.9 kV/50 MVA HTS-cable installed at Gochang test yard of Korea Electric Power Corporation, and attached voltage-leads to both the conductor and the shield. To investigate ...

We show in simulations that overdamped interacting particles in two dimensions with a randomly disordered substrate can exhibit novel nonequilibrium transport phenomena including a transverse ratchet effect, where a combined dc drive and circular ac drive produce a drift velocity in the direction transverse to the applied dc drive. The random disorder does ...

Calorimetrically determined energy losses for a series of niobium and niobium-25 at.% zirconium samples carrying an ac transport current agreed with those calculated from hysteresis loops determined by dc magnetization measurements. The results of this study showed that the energy losses in ultra-high-purity annealed Nb are less than ...

This paper describes the design of a new test system. It is under construction now and will be used to measure the AC losses of subcable from NET conductors. A special feature of the test arrangement is that the losses will be determined while the sample carries a transport current and is at the same time subjected to changing magnetic ...

Space charge in polyethylene-based insulation materials and its effect on the local electric field under a dc environment have been extensively examined over the last few decades while the behavior of space charge under ac stress has received less attention. Space charge phenomenon under ac electric fields becomes an important issue with increased ...

Driven transport of noninteracting Brownian particles in two-dimensional asymmetric channels is investigated by fully accounting for longitudinal and transverse diffusions. Bona fide two-dimensional rectification effects are reported, which cannot be explained by an approximate Fick-Jacobs kinetics, such as the characteristic curve of the current pumped by ...

Transport AC loss in a short length of 9/2 YBCO Roebel cable (nine 2 mm wide strands) is measured. The AC loss data are compared with those in a 5/2 YBCO Roebel cable (five 2 mm wide strands) as well as that in a single strand. All the strands composing the cables and the single strand are insulated and cut from the same stock ...

We investigate the AC loss of a high-0953-2048/10/8/004/img2 superconducting power-cable conductor with four layers and interlayer insulation. The electric-circuit model is applied for the calculation of the AC loss of the conductor. The result of a calculation for the AC loss shows that the calculated value is nearly equal to the ...

Self-field ac losses were measured by the conventional ac four-probe method in biaxially aligned Y{endash}Ba{endash}Cu{endash}O tapes using polycrystalline Hastelloy tapes with textured yttria-stabilized-zirconia buffer layers. The ac losses increased in proportion to the fourth power of transport ...

In this study the authors examined ac losses in a multifilamentary Bi-2223/Ag superconducting tape carrying ac transport current. The tape consisting of 85 filaments was helically wound to a single-layer coil. The losses were measured at 77 K in the frequency range from 1 Hz up to 250 Hz. ...

Chaotic noisy transport of electron pairs in a superconducting junction device (thermal-inertia ratchets) is investigated. The study shows that when the temperature is low enough, the transport of the electron pairs can be mainly chaotic; when the temperature is high enough, it can be mainly stochastic. By controlling the temperature and the amplitude of ...

The design of a Superconducting Magnetic Energy Storage (SMES) coil wound by coated conductors has been presented. Based on an existing model for coated conductor pancake coils, this paper analysed the magnetic field and current density distribution of the coil at two different operation temperatures, 77K and 22K. A comparison table of the critical ...

So far, pentazocine iontophoresis has never been studied, although pentazocine is widely used in pain management. The purpose of this study was to determine whether pentazocine transportation through a cellophane membrane could be enhanced using square-wave alternating current (AC) iontophoresis with an adjusted duty cycle and ...

In this article, the dependence of the transport ac loss on field and position is investigated for a hard superconducting cylinder, which is consisted of two concentric shells with different critical current density. The Kim model is considered for the critical state in which the critical current density is assumed ...

In this paper I discuss analytic and numerical calculations of the magnetic-field and sheet-current distributions in superconducting strips of width 2a and arbitrary thickness 2b at the center when the cross-section is an ellipse, a rectangle, and a shape intermediate between these limits. Using critical-state theory, I use several methods to determine the functional ...

We report on measurements of the ac losses of YBa{sub 2}Cu{sub 3}O{sub 7-x} conductors on technical substrates. The samples are taken from conductors 1 m long produced with an ion beam assisted deposition step in the manufacturing process yielding 1 cm wide conductors with critical currents approaching 100 A at 77.4 K. The losses due to combinations of ...

In this paper we present a method for computing transport current ac losses in interacting thin superconductors. The method solves the integral equations for the sheet current density distribution and is specifically developed for those configurations where the symmetry of the current density ...

We present a novel, general, semiclassical theory of electron transport in a carbon nanotube exposed to an external electric field. The charge carriers are treated in the framework of the simplified tight-binding model. Simultaneous exposure to rapidly oscillating (ac) and constant (dc) electric fields is considered to exemplify our theory. Nonlinear and ...

Reducing AC loss in a superconducting apparatus is one of the most important issues, and the precise measurement and estimation of AC losses are essential to reduce them. The four-terminal method is universally used as an electric measurement method of AC losses for superconducting tapes and wires. In this method, noise and inductive ...

... Extension to AC Loss Minimisation in High Temperature Superconductors ... The transport AC loss decreases more than 3 times. ...

Samples of heavily worked, cold-drawn niobium wire were heattreated at temperatures between 200 and 700 deg C to produce changes in the magnetization behavior of the material. An investigation was then carried out to determine the influence of these changes on the AC power losses produced in the wires at 4.2 K due to 50 Hz transport ...

A series of Bi-2223 ([Bi, Pb]:Sr:Ca:Cu:O = 2:2:2:3) tapes with 37 superconducting core filaments was investigated in an attempt to correlate critical current and alternating current (AC) losses with twist-pitch. The twist-pitch of these multi-filamentary tapes which were produced by the powder-in-(Ag)tube (PIT) method varies from 8, ...

... ELECTRIC CURRENT, *CARBON NANOTUBES, *FIELD EFFECT TRANSISTORS, *ALTERNATING CURRENT, *DIRECT CURRENT, CHEMICAL ...

Transport AC loss in a short length of 9/2 YBCO Roebel cable, (i.e. with 9 � 2 mm width strands), with 0.25 mm spacers between the strands is measured. The frequency varies from 59 to 354 Hz. The result is compared with the loss for a cable without spacers between the strands. Transport AC loss is decreased by ...

YBCO coated conductor is commercially available now and will be widely used in various practical power applications. In these applications, the conductor will be subjected to different kinds of mechanical stresses and strains. To achieve an optimal design of the devices, the transport characteristics under tensile, bending and torsional strains were investigated at 77 K and ...

... Title : Critical Currents and AC Losses in Model YBCO ... HALL EFFECT, ELECTRIC FIELDS, ALTERNATING CURRENT, OXIDES, COPPER ...

Time-resolved magneto-optical imaging (TRMOI) technique allows dynamic ac transport measurements on superconductors. The high time and spatial resolutions of the measurements also offer good quantitative data analysis of the MO images. YBa2Cu 3O7-delta (YBCO) was discovered as a high-temperature superconductor (HTSC) which has wide applications due to its ...

Dec 8, 2006 ... Peng ============================================ ACs Processing sites vs ITRF2005 and IGS sites Based on AC analysis reports of week 1402 ...

... Final Report, October 2005 Transverse resistivity of YBCO coated conductors for AC use ... with AC current at frequencies up to 1000 Hz ...

... Extension of the NIST AC-DC Difference ... The NIST primary standards of ac-dc difference for current are multijunction thermal converters (MJTCs). ...

motor speed control, consider the use of alternating current (AC) variable frequency drive ... AC variable frequency systems for motor speed control offer ...

... OF AC FLUX LEAKAGE, EDDY CURRENT, EMAT AND ULTRASONIC METHODS OF MEASURING SURFACE CONNECTING FLAWS IN ...

As railroads strive to cut operating and maintenance costs in an increasingly competitive transportation industry, AC propulsion and microprocessors figure prominently in their plans. New generations of locomotives and cars incorporating AC propulsion and microprocessors entered service last year, and the trend is destined to continue. ...

The voltage V(sub ab) measured between two voltage taps a and b during magnetic flux transport in a type-II superconductor carrying current I is the sum of two contributions, the line integral from a to b of the electric field along an arbitrary path C(su...

The directional diagram of the charge transport through a 'clean' and short monolayer graphene junction GJ exposed to an external electromagnetic field had been examined. We find that the photon-assisted resonant chiral tunneling across the monolayer graphene junction (GJ) causes an angular redistribution of the tunneling current density. The directional ...

Roebel cables are a promising concept for high-current coated conductor cables with low ac loss. In order to optimize their design, simulations are necessary. In this paper we compute the field and current distribution and the ac loss due to either a transport current or an ...

We present a brief review to our recent study concerning dynamic spin transport induced by AC-biased gate in low-dimensional semiconductor systems, in which dynamic spin-orbit interaction plays a crucial role. We construct a Boltzmann spin-transport model and a spin-drift-diffusion model to describe the time-dependent spin ...

Since a 100 m, 22.9 kV/50 MVA high temperature superconductor (HTS) cable system was installed at the Gochang test yard of Korea Electric Power Corp. (KEPCO) in 2005, a long-term test has been performed. In this paper, the transport characteristics of the KEPCO HTS cable system were examined by the electrical and calorimetric methods. To analyze the shield ...

Future use of coated conductors in electric power applications like transmission cables, transformers or fault current limiters is sensitive to the amount of dissipation in the AC regime. This paper analyses factors controlling AC loss of coated conductors in typical configurations: the self-field case when ...

This paper investigates the electromagnetic properties of high-temperature superconductors with a particular focus on the AC loss in coils made from YBCO superconductors. The numerical analysis and finite element modelling of the YBCO superconductors used in Cambridge�s superconducting permanent magnet synchronous motor currently in development is ...

A method for contactless measurement of the shielding critical current density and its dependence on the external magnetic field is described and analyzed. The obtained values are compared with those measured resistively on two different samples. It is shown that the shielding critical current density J{sub cs} and the intergranular ...

The voltage V{sub ab} measured between two voltage taps a and b during magnetic flux transport in a type-II superconductor carrying current I is the sum of two contributions, the line integral from a to b of the electric field along an arbitrary path C{sub s} through the superconductor and a term proportional to the time rate of change of magnetic flux ...

The tearing mode stability of the radial profiles of current density resulting from the skin effect accompanying AC modulation is calculated using a computer program. An AC component was superposed on the plasma current and a computer program was designed...

... of Defense (DoD) Issuances (current and cancelled ... OF EDDY CURRENTS UPON THE ... OF AC AND DC CONTROLLED MAGNETIC AMPLIFIERS. ...

We study the quantum version of a tilting and flashing Hamiltonian ratchet, consisting of a periodic potential and a time-periodic driving field. The system dynamics is governed by a Floquet evolution matrix bearing the symmetry of the corresponding Hamiltonian. The dc-current appears due to the desymmetrization of Floquet eigenstates, which become ...

Abstract. We consider electrical transport properties of a molecular wire under the influence of time-dependent electromagnetic fields. A formalism based on Floquet theory is derived which allows one to calculate both the dc current through the molecular wire and the associated noise power. Approximations for the case of a weak wire-lead coupling are ...

Conduction mechanism in ionic glasses is still considered one of the great challenges in physics and chemistry of glasses [A. Bunde, K. Funke, and M. Ingram, Solid State Ionics 105, 1 (1998)]. We show that consequent application of the routine percolation theory leads to the consistent description of most puzzling conduction effects for both direct current (dc) and alternating ...

We have calculated the alternating current (ac) losses of a 114 MVA high-TC superconducting (HTS) transmission cable using an electric-circuit (EC) model. The HTS cable is fabricated by Tokyo Electric Power Company and Sumitomo Electric Industries, Ltd. The EC model is comprised of a resistive part and an inductive part. The resistive part is obtained by ...

... TECHNICAL REPORT NATICK/TR-93/019 AD ALTERNATING CURRENT (AC) IMPEDANCE TESTING OF COATED TRAYCANS By Kurt Lawson ...

... Accession Number : ADA261256. Title : Alternating Current (AC) Impedance Testing of Coated Traycans. Descriptive Note : Final rept. ...

High current low voltage dc to ac conversion - hall effect, superconducting switch, & efficiency

Assembling coated conductors (CC) into flat ROEBEL bars (RACC cable) was introduced in 2005 by the authors as a practicable method of reaching high transport currents in a low AC loss cable, which is a cable design suited for application in windings. The transport current of 1.02 kA in ...

This paper reports on a local electrochemical impedance spectroscopy (LEIS) technique for mapping the ac impedance distribution, as a function of frequency, of an electrode. In LEIS, as in traditional ac impedance methods, a sinusoidal voltage perturbation between the working and reference electrode is maintained by driving an ac ...

Maintaining uniformity of properties over long distances is one of the fabrication problems encountered with the new high {Tc} superconductors. Uniform properties are crucial in long tapes or wires with high critical current since local nonuniformities can limit the current carrying capacity of the whole piece. Transport critical ...

The current rampdown phase followed by nondisruptive current termination is studied for future alternating current (AC) operations in the STOR-M tokamak. The plasma current is smoothly reduced to zero without disruptions with the rampdown rate of around m...

The influence of the geometrical parameters on the behavior of the AC losses in multifilamentary AG-BSCCO(2223) tapes is being more and more evident. Recently, the effects of configurational parameters like the ratio between the overall width and thickness of tapes without barriers as well as their precise arrangements have been put in evidence either theoretically or ...

Since large superconducting magnets are indispensable in fusion reactors or levitation vehicles, requirements for precise evaluation of A.C. losses have increased to optimize superconducting magnet design. On the other hand, direct treatment of superconductors is possible based on the critical state model. Due to limitation of present computational capability, however, it ...

Superconducting tape coils and Roebel cables are often modeled as stacks of parallel superconducting tapes carrying the same transport current. We solved, in the infinitely thin approximation, the transport current and magnetization problems for such stacks using an efficient numerical scheme based on a variational ...

The use of intermittent contact-scanning electrochemical microscopy (IC-SECM) in diffusion-limited amperometric mode to visualize and quantify mass transport through multiporous membranes is described using dentin as a model example. The IC mode of SECM employs the damping of a vertically modulated ultramicroelectrode (UME) to achieve positioning close to the receptor side of ...

We analytically study a system of spinless fermions driven at the boundary with an oscillating chemical potential. The physics is very rich: at zero driving frequency the particle current through the system is independent of the system's length; at the phase-transition frequency, being equal to the bandwidth, the current decays as n^(-alpha) with the chain ...

A photon-assisted resonant chiral tunneling across a graphene junction (GJ) induced by an external a.c. electromagnetic field is examined. We find that the a.c. field impacts the directional diagram of the charge transport across the GJ since it modulates the phase shift ? between the electron and hole wave functions. This results in ...

... the ac-dc difference of a customer's thermal current converter to the ac-dc difference of a ... range from 50 kHz to 100 kHz at currents from 1 mA to 20 A ...

Describes the action of a capacitor when dc is applied and when ac is applied. Describes and illustrates the phase relationship between voltage and current in a capacitor when ac is applied. Compares the voltage and current relationship in an inductive an...

The program describes the action of a capacitor when DC is applied and when AC is applied. It describes and illustrates the phase relationship between voltage and current in a capacitor when AC is applied. It also compares the voltage and current relation...

The voltage V ab measured between two voltage taps a and b during magnetic flux transport in a type-II superconductor carrying current I is the sum of two contributions, the line integral from a to b of the electric field along an arbitrary path C s through the superconductor and a term proportional to the time rate of change of magnetic flux thrugh the ...

Ellipsometric measurements on anodic oxide films grown on niobium in phosphoric acid were found to show behavior characteristic of films consisting of two layers, but films grown in chloride solution showed the behavior typical of uniform films. It was concluded that as with tantalum, phosphate but not chloride ions are taken up in the outer part of the film, which grows by metal ion motion. The ...

With the current high level of security awareness in the transit environment and the considerable proportion of bomb threats that are hoaxes, law-enforcement and transit-security officials need decision-making tools to investigate threats before taking ac...

A Survey of Wireless Sensor Networks Technology I. Khemapech, I. Duncan and A. Miller School,ishbel,alan}@dcs.st-and.ac.uk Abstract-Wireless Sensor Networks were first used in military missions. They are currently deployed and components, reliable transport protocol and congestion control research in wireless sensor networks. Each

wafers after the deposition of under�bump metalization and indium bumps. A number of sensors were for transport and bump bonding. All sensors were bump bonded to PSI30/AC30 readout chips [12] which allow analog substantially after bump�bonding to the readout chips. Although the cause of the increased current is not clear

Particle transport by a planar electric curtain is studied with a discrete element method (DEM). The electric curtain is consists of four sets of parallel stripe electrodes embedded in an insulating material. The electrodes are connected to a four-phase square-wave AC source and produce a traveling wave above the curtain plate. Current ...

It is pointed out that dc drives will be the logical choice for current production electric vehicles

Inductance vs AC current; 0 DC bias; ikHz. 25. A. AC and DC Current Dependence of On-Chip Inductors. C.Ahn', T. Liakopolisa, U. Lienewegb, E. Wesselingb ...

... (PATENT). Descriptors : *PATENTS, *ALTERNATING CURRENT, *PULSES, *CONVERTERS, *ELECTRON BEAMS, *RELATIVITY THEORY ...

This need soon evaporated after Nikola Tesla's discovery of alternating current (AC) for transmitting power

We investigate transport properties of molecular junctions under two types of bias--a short time pulse or an ac bias--by combining a solution for Green's functions in the time domain with electronic structure information coming from ab initio density functional calculations. We find that the short time response depends on lead structure, bias voltage, and ...

We investigate transport properties of molecular junctions under two types of bias-a short time pulse or an ac bias-by combining a solution for Green's functions in the time domain with electronic structure information coming from ab initio density functional calculations. We find that the short time response depends on lead structure, bias voltage, and ...

The voltage V_ab measured between two voltage taps a and b during magnetic flux transport in a type-II superconductor carrying current I is the sum of two contributions, the line integral from a to b of the electric field along an arbitrary path Cs through the superconductor and a term proportional to the time rate of change of magnetic flux through the ...

This paper analyzes the interactions between the ac voltages and the dc current in weak ac/dc interconnections. The response of the voltage is expressed in terms of the basic parameters of the interconnection and the impact of these parameters on the voltage waveshapes is analyzed. Finally, indexes describing the distortion of the ...

The ac characteristics of a double-conversion system are investigated. Using a simple method, the harmonic composition of the alternating currents are determined as a function of the connection type of the ac/dc rectifier and of the parameters characterizing the dc/dc chopper operations. It is shown that the best ...

A system and method for determining stator winding resistance in an AC motor is disclosed. The system includes a circuit having an input connectable to an AC source and an output connectable to an input terminal of an AC motor. The circuit includes at least one contactor and at least one switch to control current ...

The purpose of this study was to determine whether lidocaine can be efficiently transported across a cellophane membrane using a square-wave alternating current (AC) with an adjusted duty cycle. Three voltages at 1 kHz with 6 duty cycles were applied for 60 min to the diffusion cells on both sides of the cellophane membrane. The donor ...

The dynamical conductance of electrically contacted single-walled carbon nanotubes is measured from dc to 10 GHz as a function of source-drain voltage in both the low-field and high-field limits. The ac conductance of the nanotube itself is found to be equal to the dc conductance over the frequency range studied for tubes in both the ballistic and diffusive limit. This clearly ...

The AC magnetic losses at power frequencies (60 Hz) were investigated for mono- and multifilament Ag-sheathed (Bi, Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub y} (BSCCO-2223) tapes with similar transport critical current (I{sub c}) values at 77 K. The multifilament sample exhibited higher losses than the monofilament under the same ...

Between 2000 and 2003 Transportable AC Systems (TACS) and Hybrids (HTACS) were developed and demonstrated to support the electrical requirements of Command Centers in the field. Primary power was provided by unbreakable, lightweight, flexible solar module...