... Abstract : Results are presented on the AC and DC characteristics of Wausau granite which show that excess AC losses at low temperatures are ...
DTIC Science & Technology
In order to apply widely the superconductivity technology to electric power equipments, the development and evaluation on the AC superconducting cables have been conducted in the Central Research Institute of Electric Power Industry. The superconducting c...
National Technical Information Service (NTIS)
It is demonstrated for the first time that a relatively large cryostable superconducting coil can be pulsed with relatively low ac losses at high ramping rates. The low ac losses with limited current sharing have been achieved by insulating the surface of...
We have manufactured a small circular superconducting coil impregnated with epoxy fibreglass. The coil was wound from a Bi-2223/Ag superconducting wire and it was tested in liquid nitrogen at 77 K. Current-voltage characteristic and the AC losses of the coil were measured and compared with the measurements on the original tape. The ...
NASA Astrophysics Data System (ADS)
We present here results of our study of the 5-m-long AC transmission tine model with 1 kA current capability at 77 K. Primary attention was paid to the current characteristics and AC losses in individual tapes and in the core of the cable. The losses were...
... AC Loss Minimisation in High Temperature Superconductors ... Extension to AC Loss Minimisation in High Temperature Superconductors ...
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 ...
Theoretical and experimental studies of the ac losses in continuous fine filament superconductors and in situ Nb3Sn superconductors are reported. The results indicate that surface currents may play a major role in determining the loss and critical current characteristics of fine filament superconductors. In situ ...
Energy Citations Database
It is demonstrated for the first time that a relatively large cryostable superconducting coil can be pulsed with relatively low ac losses at high ramping rates. The low ac losses with limited current sharing have been achieved by insulating the surface of the basic cable with thin organic film. The ...
We present here results of our study of the 5-m-long AC transmission tine model with 1 kA current capability at 77 K. Primary attention was paid to the current characteristics and AC losses in individual tapes and in the core of the cable. The losses were measured as a function of ...
DOE Information Bridge
High temperature superconducting (HTS) cables with RE-123 coated conductors are expected to lower AC loss compared to that with BSCCO cable. Sumitomo Electric Industries, Ltd. (SEI) has been developing not only BSCCO wires but also RE-123 coated conductors. Recently, SEI has developed a RE-123 coated conductor with a new type of textured metal substrate ...
This report discusses the AC losses in the MICE channel magnets during magnet charging and discharging. This report talks about the three types of AC losses in the MICE magnets; the hysteretic AC loss in the superconductor, the coupling AC ...
The magnetization loss density in stacked GdBa2Cu3O7?? coated conductor was measured using a SQUID magnetometer in a magnetic field normal to the tape surface to investigate the effect of stack on the magnetization loss. The AC loss characteristics are successfully collapsed to a single curve ...
The AC loss characteristics of a magnet-superconductor system were studied with the magnet fixed to the free end of an oscillating cantilever located near a stationary melt-textured YBCO pellet. Below a threshold AC field amplitude {approx}2Oe, the dissipation of the oscillator is amplitude-independent, ...
... YBCO Coated Conductors with Reduced AC Losses ... YBCO Coated Conductor, AC losses, RABiTS, Superconductor, Maganetic Properties ...
... Extension to AC Loss Minimisation in High Temperature Superconductors ... The transport AC loss decreases more than 3 times. ...
AFRL-PR-WP-TP-2006-208 AC LOSS REDUCTION OF YBCO ... SUBJECT TERMS AC losses, coated conductors, YBCO, multifilamentary 16. ...
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 ...
This paper proposes a new magnetic levitation scheme which is able to generate levitation force for all speeds including a standstill. Auxiliary wheels which are needed in EDS MAGLEV vehicle can be eliminated. This scheme uses AC superconducting magnets to generate levitation force. In this paper, magnetic fields, forces and power dissipations generated by ...
The frequency characteristic of ac losses in aluminum-stabilized superconducting conductors are investigated in order to elucidate their loss mechanism under a changing transverse magnetic field. AC loss measurement is carried out for the short and straight sample conductor ...
The electrical characteristics of a piezoelectric vibrator in the open-circuit transient state and its applications are investigated. The characteristics include peak voltages, time constants and oscillation frequency of a voltage transient response induced at the input terminals of the vibrator. These time constants can also be adopted to estimate the ...
... Accession Number : ADA461815. Title : AC Loss Reduction of YBCO Coated Conductors by Multifilamentary Structure. Descriptive ...
... Title : AC LOSSES OF SUPERCONDUCTING COMPOSITES WITH 8 MU-M NBTI FILAMENTS IN A DC MAGNETIC FIELD WITH A ...
(>1000 m). Species characteristic of the montane for- est belt include Podocarpus, Weinmannia, Symplocos
E-print Network
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 resistive voltage of ...
A two-dimensional numerical diffusion model which estimates self-field ac losses in High-Tc Superconducting (HTS) tapes is developed. The HTS tape is simulated as a nonlinear conductor whose equivalent resistivity is derived from a power law E-J characteristic. Results of various field quantities and ac ...
Measurements of 50-Hz ac losses were performed using three characteristic NbTi coil samples with ultrafine filaments and a Cu--CuNi mixed matrix at fields up to 1 T and at 4.2 K. Critical current and quenching current densities were measured under dc and ac conditions as well as the losses with ...
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 ...
A simple model gave utilized for calculation of magnetization effects on ac loss and sextupole for Energy Doubler dipole magnets. The calculation in the simple model gave an underestimation of ac loss by about 30%. Results of computation on ac harmonics were also described.
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 ...
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 AC loss and ...
A study has been made of ac loss characteristics of type-II superconductors due to hysteresis losses in the superconducting material and eddy current losses in the normal matrix in the absence of an applied field. Losses were measured for Nb$sub 3$Sn tapes, a Nb ...
Lead monoxide filled isophthalate resin particulate polymer composites were prepared with different filler concentrations and investigated for physical, thermal, mechanical and gamma radiation shielding characteristics. This paper discusses about the dielectric properties of the composites. The present study showed that the dielectric constant (?'), dielectric ...
AC superconducting composite wires for 50-60 Hz application are very susceptible to disturbances due to wire motions, because matrices of the wires are highly resistive CuNi. Instability of the wires is one of the most serious problems in developing AC wires of large current capacity. An effective technique to reduce the wire motions is to impregnate the ...
The ac loss characteristics of coated conductors are dominated by the magnetic field component normal to their superconductor layer. Multilayer cables as well as monolayer cables consisting of 4 mm-wide coated conductors (named 4 mm cables) and those consisting of 2 mm-wide coated conductors (named 2 mm cables) were designed, and ...
VLF (very low frequency) mode instability with parallel AC electric field was studied for generalized loss-cone distribution with an index j, which is reducible to bi-Maxwellian, loss-cone and delta function for j = 0,1 and ?. The particle trajectories and dispersion relation are obtained through a kinetic approach and method of ...
Researches and developments on a superconducting fault current limiting (SFCL) system have been done for several decades. The SFCL system, which is using a high temperature superconducting (HTS) conductor such as Bi-2212 bulk and YBCO film, has recently become technically available. In this work, we are developing a 22.9 kV/25 MVA SFCL system for a power distribution network. A Bi-2212 bulk SFCL ...
Low AC loss and high current density NbTi/Cu/CuNi double stage cabling superconductor for quick response superconducting generator (SCG) has been developed. Its characteristics were measured by short sample and several coil models. The critical current of 14kA at 6T and the AC loss of ...
This paper reports on Super-GM which is conducting basic designs of 70 MVA superconducting generators and developing superconductors, for establishing the application technology of superconducting generators. For generators, it is intended to develop a slow response excitation type generator with emphasis placed on stability, higher current density for enhancement of ...
This report discusses the AC losses in the MICE channelmagnets during magnet charging and discharging. This report talks aboutthe three types of AC losses in the MICE magnets; the hysteretic AC lossin the superconductor, the coupling AC loss in the ...
Ac loss measurements have been performed in samples of a prototype conductor being developed for application in the central solenoid of NET. Two types of losses have been measured: hysteresis losses in the strand, and coupling losses in the strand, subcab...
The theory and calculation of a.c. losses in type II superconducting materials and superconducting coils are presented. The calculated losses are compared to loss-measurements in solenoids performed by several laboratories. Methods of loss measurements are described. (author)
Page 1. AFRL-PR-WP-TP-2006-210 LOW AC LOSS STRUCTURES IN ... 2, JUNE 2005 2827 Low AC Loss Structures in YBCO Coated Conductors ...
This paper discusses the physics of ac losses in type-II superconductors and in multifilamentary superconducting-normal composite conductors. As an introduction, the ac eddy-current losses in a homogeneous normal conducting cylindrical specimen subjected ...
This lecture discusses the physics of ac losses in type-II superconductors and in multifilamentary superconducting-normal composite conductors. As an introduction, the ac eddy-current losses in a homogeneous normal conducting cylindrical specimen subjecte...
The winding technology with high current capacity is one of the important factors in power application of 20 MVA/66 kV-class superconducting power transformers. High-current power transformer is achieved by transposed conductors made of Rare Earth-based superconducting coated conductors. By transpositions, the improvement of uniformity of strand current distribution makes it possible to reduce the ...
This paper investigates electrical transient characteristics of a Rosen-type piezoelectric transformer (PT), including maximum voltages, time constants, energy losses and average powers, and their improvements immediately after turning OFF. A parallel resistor connected to both input terminals of the PT is needed to improve the transient ...
PubMed
The purpose of this paper is to experimentally verify the current limiting characteristics of a two material magnetic device consisting of a ferrite and permanent magnet material. A resonant pulsed excitation source and a 60 Hz ac source are used to test the characteristics of the device. The experiments confirm that there is a ...
... Accession Number : ADA481255. Title : YBCO Coated Conductors with Reduced AC Losses. Descriptive Note : Final technical rept. ...
... Accession Number : ADA346511. Title : Program to Study AC Loss in High-Tc Superconductors. Descriptive Note : Final technical rept. ...
... Accession Number : ADA038393. Title : Measurements of AC Losses in Superconductors below Hc1. Descriptive Note : Final rept. Jan 74-Jun 76,. ...
... Title : Low AC Loss Structures in YBCO Coated Conductors With Filamentary ... Personal Author(s) : Barnes, Paul N. ; Levin, George A. ; Varanasi ...
... Abstract : This report results from a contract tasking University of Cambridge as follows: The contractor will investigate: 1) AC losses of appropriate ...
... report results from a contract tasking University of Cambridge as follows: The contractor will investigate: (a) Measure the AC losses of appropriate ...
... Title : Critical Currents and AC Losses in Model YBCO ... HALL EFFECT, ELECTRIC FIELDS, ALTERNATING CURRENT, OXIDES, COPPER ...
... Using the two-dimensional FEM model for electromagnetic field analysis of coated conductors, the AC losses at various conditions were calculated ...
... Title : AC LOSSES IN A MULTIFILAMENTARY NB3AL/CU COMPOSITE SUPERCONDUCTOR MADE BY A JELLY ROLL PROCESS. ...
0953-2048/9/3/015/img7 multifilamentary superconducting wires for a.c. use were developed by the bronze method using Cu diffusion barrier techniques. To reduce a.c. losses, the filament diameter was designed to be less than 0953-2048/9/3/015/img8 and the final resistivity of the bronze matrix was increased using a Cu alloy diffusion ...
The current distribution in a superconducting transformer will be concentrated in the main windings under steady-state conditions, and when a fault causes the current to exceed the critical current in the main windings, the current shifts to auxiliary windings. This design approach leads to extremely low transformer losses provided that advanced superconductors are utilized. ...
We investigate the flux penetration into the system of two (super- or normal conducting) regions when some of the regions are 'shielded' by the other one. The shield material may also consist of a normal conductor or superconductor. For simplicity, we consider this system in the slab geometry. The results indicate that shielding a superconducting cable by normal metal can decrease the total ...
A large amount of power (5 GW or more) can be transmitted through a dc superconducting power transmission line (SPTL) which has the highest power density and efficiency of any known transmission line. Although the SPTL has zero resistance to pure dc, it experiences hysteresis and resistive losses under ac and ripple. Under faults, the current may be driven ...
... Accession Number : AD0131786. Title : STUDY ON AC GENERATING MACHINE CHARACTERISTICS FOR AIRCRAFT ELECTRIC SYSTEMS. ...
The possibility of employing superconductors for the field windings of large AC generators, providing essentially unlimited field capability and eliminating field ohmic losses is discussed. Some of the benefits and challenges in reducing this exctting new technology to practice in large AC generators are outlined. The ...
The effects of magnetic annealing on the magnetic characteristics and magnetic losses of amorphous ribbons Fe78Si10B12 were studied. The annealing temperature was chosen at 400�C, being lower than the Curie temperature 440�C. A magnetic field of 30 Oe was applied during the heat treatment, in a direction at an angle ? to the length of the ribbon, with ...
... TERMS magnetization losses, superconductor, YBCO coated ... of coated super- conductors in demanding ac ... Theory of Superconductors Tay- lor and ...
... ALTERNATING CURRENT, CRITICAL TEMPERATURE, LOSSES, HYSTERESIS, UNITED KINGDOM, YTTRIUM BARIUM COPPER OXIDES. ...
... SUPERCONDUCTORS, *ELECTRIC FIELDS, *ALTERNATING CURRENT ... SURFACE PROPERTIES, THINNESS, SCALAR FUNCTIONS, LOSSES ...
... The main obstacle to the use of superconductors in electrical machines in ... superconducting cylinder (ie the losses in the superconductor plus the ...
... MATHEMATICAL MODELS, ALTERNATING CURRENT, LOSSES, MAGNETIZATION, COPPER OXIDES, YTTRIUM OXIDES, BARIUM OXIDES ...
The dc hysteresis behavior of the magnetization and the 60-Hz ac loss characteristics were both measured at 4.2 K as a function of applied field to 2000 Oe on YBa{sub 2}Cu{sub 3}O{sub 7} and on iron-substituted YBa{sub 2}(Cu{sub 1}{sub {minus}{ital x}}Fe{sub {ital x}}){sub 3}O{sub 7} samples with {ital x}=0.04 and 0.10. From the dc ...
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 ...
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 current in this ...
The objective of the program was to study the feasibility of Nb3Ge being used as an AC superconducting power transmission cable material. Specifically, the program was to measure AC losses in available samples of Nb3Ge and find under what conditions the l...
... are superconducting. The design of such a machine is dominated by the AC losses which occur in the armature. Most superconducting ...
The guidance force of the YBCO bulk over a NdFdB guideway used in the high-temperature superconducting maglev vehicle system was decayed by the application of the AC external magnetic field. In our previous work, we explained that the decay was due to the temperature rise of the HTS bulk caused by AC losses. In this paper, we adopted ...
In the present study, we fabricated magnesium doped apatite cement (md-AC) with rapid self-setting characteristic by adding the mixed powders of magnesium oxide and calcium dihydrogen phosphate (MO-CDP) into hydroxyapatite cement (HAC). The results revealed that the md-AC with 50 wt% MO-CDP could set within 6 min and the compression ...
AC losses must be considered in SMES during discharging of the coil. This is especially true for very fast discharges. In particular, the SMES/Engineering Test Model (ETM) should be able to demonstrate the capability to discharge at 400 MW for 100 seconds. It is important to quantify AC losses to ascertain its ...
The dielectric constant and the dielectric loss of thin films of metal-free phthalocyanine dispersed in polycarbonate using ohmic gold electrodes are investigated in the frequency range 20-105 Hz and within the temperature range 300-388 K. The frequency dependence of the impedance spectra plotted in the complex plane shows semicircles. The Cole-Cole diagrams have been used to ...
... Accession Number : AD0666432. Title : CHARACTERISTICS OF A HIGH PRESSURE AC ARC HEATER SYSTEM. Descriptive Note : Rept. no. ...
Important key technologies of a high-temperature superconducting (HTS) transformer may include the HTS wire technology, cooling, AC loss reduction, large current technology, and cryogenic temperature insulation. Among them, the cryogenic temperature insulation technology will be specifically a core technology for ensuring reliability for the smaller size, ...
The 138 kV Forced Cooling Test Facility at Waltz Mill is described in detail. Design information for system components as well as operational and maintenance procedures are given. Of significant interest is the design and construction of the cable itself which represents a major stride forward in the ability to instrument high voltage cables. Results of preliminary testing characterizing ...
The feasibility of superconductors for alternating current use depends on successful reduction of losses. Moreover, the demand for large field amplitudes is a stimulation for investigating the nature of a.c. losses (e.g. in the set of poloidal coils in a ...
The Low Energy Demonstration Accelerator (LEDA) facility located at Los Alamos National Laboratory (LANL) accelerates protons to an energy of 6.7 MeV and current of 100 mA operating in either a pulsed or cw mode. Two types of current measurements are used. The first is an AC or pulsed-current measurement which uses three LANL built toroids. They are placed in the beamline in ...
Four groups of superconducting power transmission cables composed of coated conductors with 4.0 mm width and 2 �m superconductor thickness have been designed, including mono-layer, two-layer, four-layer and six-layer cables. In each group, three types of cables have been constructed with gaps of different size between adjacent coated conductors, which are classified into small gap, medium gap ...
An empirical relation is presented which allows simple computation of volume-averaged winding fields from central fields for coils of small rectangular cross sections. This relation suggests that, in certain applications, ac-loss minimization can be accomplished by use of low winding densities, provided that hysteresis losses are independent of winding ...
Initial operational characteristics of a wind tunnel electromagnetic balance utilizing superconducting coils are reported. Both dc and ac superconducting coils are used for balancing and measuring 3-component aerodynamic forces on simple models in Mach 3, room temperature flow. Liquid helium boil-off measurements, corresponding to a wide range of ...
Commercial calcium silicate bearing Portland cement type III (PC III), in the form of agglomerated cement sorbent (ACS) pellets, is being investigated for in-situ desulfurization of fuel gases and for improved coal gasification. The preparation procedure and conditions for pelletizing agglomerated cement sorbent (ACS) by a low energy, low cost ...
Reduction of ac losses in applied ac fields can be accomplished through either the creation of filaments and bridging in YBCO coated conductors or an assembly of narrow width YBCO tapes. The ac losses for each of these geometries were measured at 77 K in perpendicular ac ...
AC loss is one of the main issues in the design of the CICC used for PF and TF coils of superconducting tokamak. A preliminary calculation of AC loss for the designed HT-7U CICCs used for TF magnets is given in this paper. We only consider the hysteresis and coupling losses related to ...
Magnetization AC losses in striated YBCO conductors in a perpendicular applied AC magnetic field were investigated with special regard to the coupling current AC loss (CCAC). The AC loss of YBCO samples of different length L was measured by using ...
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MedlinePLUS
... motion compensation will be assumed to avoid any target signal loss incurred in integration. ... the DC part &(v) and the AC spectrum pAc(v) due to ...
Development of the superconducting transformer is arguably the most difficult of the ac power applications of superconductivity - this is because of the need for very low ac losses, adequate fault and surge performance, and the rigors of the application e...
AC losses increased rapidly with frequency and quadratically with AC amplitude. Above about 2 hz, the effective resistance of the control coils exceeds that ...
NASA Website
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 ...
Persimmon (Diospyros kaki Thunb.) fruit are usually classified as climacteric fruit; however, unlike typical climacteric fruits, persimmon fruit exhibit a unique characteristic in that the younger the stage of fruit detached, the greater the level of ethylene produced. To investigate ethylene induction mechanisms in detached young persimmon fruit, we cloned three cDNAs ...
PubMed Central
Trapped field characteristics are one of the key factors in the application of high-temperature superconducting bulk, such as magnetic levitation systems, motors, bulk magnets and so on. The immutable trapped field is required in superconducting bulk applications as a quasi-permanent magnet, however, the trapped field is influenced and changed by a time-varying external ...
It is necessary to develop HTS conductors with a large current capacity and low AC loss characteristics for practical use of HTS power devices. For large capacity power applications, HTS tapes such as Bi-2223 tapes and YBCO coated conductors are assembled. So, it is important to evaluate the characteristics of ...
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 ...
In this paper a description is given of a method to measure calorimetrically ac losses in superconducting samples. The boil-off gas is stored below the liquid helium level in a measuring tube. Losses in the range of 1 mW up to 100 mW can be measured with an accuracy of 3%. Results of measurements of ac ...
... ZN ALLOY MATERIAL INTO AN AC ARC DISCHARGE AND CONCENTRATION DEPENDENCE OF THE INTENSITY OF ALUMINIUM AND ZINC ...
Language: English ...
NBII National Biological Information Infrastructure
AcNPV (Autographa californica nuclear polyhedrosis virus) and BmNPV(Bombyx mori nuclear polyhedrosis virus) are two principal insect-baculovirus expression systems, each having different characteristics. AcNPV has a wider host range and can infect a series of cell lines thus making it suitable for cell suspension culture expression, ...
... Title : ANODIC CHARACTERISTICS OF Ni RICH ALLOYS MEASURED BY THE AC IMPEDANCE METHOD,. Corporate Author : ...
A model 5 m cable prototype was constructed using American Superconductor second generation (2G) high temperature superconductor (HTS) wires - 344 superconductors, produced with the MOD/RABiTSTM process. The model cable consists of two helically counterwound layers of brass-laminated tapes. Twist pitches were calculated to provide uniform current distribution between the two cable layers. The NiW ...
Low work function is a vital life-determining characteristic of fluorescent lamp electrodes. The work function of a fluorescent lamp electrode increases due to the loss of Ba atom from the electrode. Hence the rate of Ba atom loss controls the lifetime of the lamp. However the loss mechanism and the optimum ...
High-temperature-superconductor (HTS) current leads are suitable for AC applications because of lower AC loss during operation as well as their lower thermal conductivity. The authors have designed, fabricated and tested a 2 kA HTS current lead system. It is composed of copper leads for the higher temperature region and HTS elements ...
We have tried to determine the effects of 60Co gamma irradiation on properties of Au/SnO2/n-Si (MOS) structures such as dielectric constant (??), dielectric loss (??), tangent loss (tan ?) and ac conductivity (?ac). Three samples were fabricated with different deposition time. The samples were irradiated using a ...
This lecture discusses the physics of ac losses in type-II superconductors and in multifilamentary superconducting-normal composite conductors. As an introduction, the ac eddy-current losses in a homogeneous normal conducting cylindrical specimen subjected to an alternating applied magnetic field are briefly ...
ac losses of superconducting solenoidal coils were investigated with a calorimetric method while applying a current or uniform magnetic field of 50 Hz with a sinusoidal wave form. The peak value of the ac current was varied from 0 to 15 rms A and that of the ac magnetic field from 0 to 0.02 T. These experimental ...
A report is given of calorimetric measurements of the ac losses of a small superconducting coil wound from a filament superconductor designed for low ac losses (filament phi = 8 $mu$, number of filaments 1045, CuNi barriers). The coil was pulsed with a maximum dB/dt = 480 kG/s. Further the ...
This study investigated the combined function of the Autographa californica multiple nucleopolyhedrovirus overlapping genes ac16 (BV/ODV-E26, DA26) and ac17. Ac17 is a late gene and the promoter is within the ac16 open reading frame. A double ac16-ac17 knockout virus was ...
The final goal of the program is to establish standard measurement practices and a standard reference material for calibration of apparatus. In this paper the authors discuss a comparison of several techniques for measuring ac losses in superconductors. The techniques are divided into either a calorimetric or electronic type.
The objective of the study is to estimate the probability of failure of the battery system of a nuclear power plant due to loss of ventilation in the battery room during AC blackout. This is part of the more general problem of the interaction between non-...
Nov 24, 2008 ... In a NASA SBIR Phase I and Phase II program we want to develop low AC loss MgB2 superconductors for the stators of synchronous motors or ...
An improved electronic method for measuring ac losses in superconducting cables of lengths from 1m to 10m has been developed and is described. This method compensates for phase shifts in the measuring circuit elements and for imbalance of the difference a...
Energy dissipation, which is also called AC loss, of a composite multifilamentary superconducting wire is one of the most fundamental concerns in building a stable superconducting magnet. Characterization and reduction of AC losses are especially importan...
The measurement of ac losses in superconducting cables by calorimetric means is necessary as a verification of electronic measurements on short high-current models and because the present method of electronic measurement is not applicable to longer cables...
A calorimeter has been developed to measure the total core loss in small samples of magnetic materials which are not suited to conventional measurement techniques. The method is similar to the helium boil-off calorimeter used in some cases to measure ac l...
AC losses in full length and 1.5 m model SSC collider dipoles were successfully measured by the direct observation of energy flow into and out of magnets during a ramp cycle. The measurement was performed by using two double-integrating type digital volt ...
Since 1995 Southwire Company and Oak Ridge National Laboratory (ORNL) have jointly designed, built, and tested nine, l-m long, high temperature superconducting (HTS) transmission cable prototypes. This paper summarizes the AC loss measurements of five of ...
A new cryostat cooled by a closed-cycle Cryomech GB-37 cryocooler for superconductor measurements at temperatures down to 20 K is described. The sample is conductively coupled to the cold stage so as to minimize vibration and thermal stresses. AC losses h...
Age-related bone loss is associated with changes in bone cellularity with characteristically low levels of osteoblastogenesis. The mechanisms that explain these changes remain unclear. Although recent in vitro evidence has suggested a new role for proteins of the nuclear envelope in osteoblastogenesis, the role of these proteins in bone cells ...
The nitrate removal process was evaluated using a fixed-bed column packed with amine-crosslinked wheat straw (AC-WS). Column sorption and desorption characteristics of nitrate were studied extensively. Solid-state (13)C NMR and zeta potential analysis validated the existence of crosslinked amine groups in AC-WS. Raman shift of the ...
From the time constant and the hysteresis loss measurements of the subcables, it is estimated that approximately 60% of the ac losses of the ANL 3.3 MJ coil at 6 T/s of the central field are due to the losses within the 19-strand subcable itself. The remaining 40% of the losses seem to come ...
... For D6AC the use of such inhibitors gives promise of being able to avoid hydrogen ebrittlement. ... 2 1. Crevice Corrosion Characteristics of D6AC .. ...
... Abstract : The theory of magnetohydrodynamic power generators is presented. ... sectional area flows; end losses; AC generation; cycle efficiencies ...
A superconducting tape having reduced AC losses. The tape has a high temperature superconductor layer that is segmented. Disruptive strips, formed in one of the tape substrate, a buffer layer, and the superconducting layer create parallel discontinuities in the superconducting layer that separate the current-carrying elements of the superconducting layer ...
DOEpatents
