Distinction between critical current effects and intrinsic anomalies in the point-contact Andreev reflection spectra of unconventional superconductors

In this work,we discuss the origin of several anomalies present in the point-contact Andreev reflection spectra of（Li1-xFex）OHFeSe,LiTi2O4,and La2-xCexCuO4.While these features are similar to those stemming from intrinsic superconducting properties,such as Andreev reflection,electron-boson coupling,multigap superconductivity,d-wave and p-wave pairing symmetry,they cannot be accounted for by the modified Blonder–Tinkham–Klapwijk（BTK） model,but require to consider critical current effects arising from the junction geometry.Our results point to the importance of tracking the evolution of the dips and peaks in the differential conductance as a function of the bias voltage,in order to correctly deduce the properties of the superconducting state.

Current perspectives on the antidepressant-like effects of guanosine

Purines have a recognized importance as intercellular mes- sengers. These molecules play an important role in the de- velopment and maintenance of the central nervous system （CNS）, as well as in its response to pathological conditions. Both adenine and guanine-based purines can be released from astrocytes, where they play a relevant role as extracel- lular signaling molecules. Particularly, the nucleoside gua- nosine has been proposed as an extracellular molecule that regulates the response of CNS to damage. Following injury, this nucleoside attains high concentrations in the extracel- lular space, where it activates multiple signaling pathways.

Energetic Ion Effects on the Ion Saturation Current

The ion saturation current is very important in probe theory, which can be used to measure the electron temperature and the floating potential. In this work, the effects of energetic ions on the ion saturation current are studied via particle-in-cell simulations. It is found that the energetic ions and background ions can be treated separately as different species, and they satisfy their individual Bohm criterion at the sheath edge. It is shown that the energetic ions can significantly affect the ion saturation current if their concentration is greater than root T-e/(gamma T-i2(i2)), where T-e is the electron temperature, and gamma(i2) and T-i2 represent the polytropic coefficient and temperature of energetic ions, respectively. As a result, the floating potential and the I-V characteristic profile are strongly influenced by the energetic ions. When the energetic ion current dominates the ion saturation current, an analysis of the ion saturation current will yield the energetic ion temperature rather than the electron temperature.

Effect of Current Density on Al Alloy Microplasma Oxidation

The microplasma oxidation process of LY 12 Al alloy in Na2SiO3-KOH-NaAL2 system has been studied. The voltage-time curve of oxidation process is changed with the variation of current densities. The voltage breakdown and hardness of coating increase with increasing current density. The phase composition, morphologies, element and the distribution of ceramic coating are investigated by XRD, EPMA.

Effect of excitation current intensity on mechanical properties of ZL205A castings solidified under a traveling magnetic field

The effect of excitation current intensity on the mechanical properties of ZL205 A castings solidified under a traveling magnetic field was studied. The results of the experiment indicate that the excitation current intensity of the traveling magnetic field has a great influence on the mechanical properties of the ZL205 A castings. When the excitation current intensity is 15 A, the tensile strength and elongation of ZL205 A alloy castings increase 27.2% and 67.7%, respectively, compared with those of the same alloy solidified under gravity. The improvement of mechanical properties is attributed to the decrease of micro-porosity in the alloy. Under the traveling magnetic field, the feeding pressure in the alloy melt before solidification can be enhanced due to the electromagnetic force. Moreover, the melt flow induced by the traveling magnetic field can decrease the temperature gradient. The feeding resistance will be increased because the temperature gradient decrease. So traveling magnetic field has an optimum effect on feeding.

Axial Shock in a Cylindrical Plasma with Current

Hugoniot relations of a two-dimensional axial shock with current and magnetic field in a cylindrical shock tube were investigated by a numerical method. The radial profiles of the magnetic field, electric current, pressures, flow velocities and temperatures between the up- and down-stream radial force-balanced plasma of the shock were revealed by numerical analysis. It is clearly found that the axial shock can lead to two effects： one is an inverse skin effect （i.e., the current density rises towards the center of the conductor）, the another is a reversed current effect which occurs near the edge and about a half radius. It is also found that the radial gradient of pressure, density and temperature all become very large near the center due to the axial shock.

A complete small-signal HBT model including AC current crowding effect

An improved small-signal equivalent circuit of HBT concerning the AC current crowding effect is proposed in this paper. AC current crowding effect is modeled as a parallel RC circuit composed of Cbi and Rbi, with distributed base-collector junction capacitance also taken into account. The intrinsic portion is taken as a whole and extracted directly from the measured Sparameters in the whole frequency range of operation without any special test structures. An HBT device with a 2 × 20 μm^(2) emitter-area under three different biases were used to demonstrate the extraction and verify the accuracy of the equivalent circuit.

Speed Measurement Feasibility by Eddy Current Effect in the High-Speed MFL Testing

It is known that eddy current effect has a great influence on magnetic flux leakage testing(MFL).Usually,contacttype encoder wheels are used to measure MFL testing speed to evaluate the effect and further compensate testing signals.This speed measurement method is complicated,and inevitable abrasion and occasional slippage will reduce the measurement accuracy.In order to solve this problem,based on eddy current effect due to the relative movement,a speed measurement method is proposed,which is contactless and simple.In the high-speed MFL testing,eddy current induced in the specimen will cause an obvious modification to the applied field.This modified field,which is measured by Hall sensor,can be utilized to reflect the moving speed.Firstly,the measurement principle is illustrated based on Faraday’s law.Then,dynamic finite element simulations are conducted to investigate the modified magnetic field distribution.Finally,laboratory experiments are performed to validate the feasibility of the proposed method.The results show that Bmz(r1)and Bmx(r2)have a linear relation with moving speed,which could be used as an alternative measurement parameter.

Effect of Electric Current on Diffusion of Aluminum in Ti3AlC2 into Zirconium Alloy

The spark plasma sintering（SPS） method was used to study the mechanism of reaction interface between Zr and Ti3AlC2 with electric current going through it. It was found that electric current greatly reduced the bonding temperature of Zr and Ti3AlC2. By the micro-structure analysis of the interface through SEM/EDS, it was found that Al atoms diffused from the Ti3AlC2 substrate into the Zr side and reacted with Zr to form the Zr-Al compounds at the interface, which is the strengthening mechanism of Ti3AlC2-Zr bonding. The thickness of reaction layers（Zr-Al alloy） was from 0.879 to 13.945 mm depending on different sintering condition. Current direction, heating rate, soaking time, pulse patterns all influenced the diffusion of Al atoms which affected the joining quality of Zr and Ti3AlC2.

Effect of pad geometry on current density and temperature distributions in solder bump joints

Three-dimensional thermo-electrical finite element analyses were conducted to simulate the current density and temperature distributions in solder bump joints with different pad geometries.The effects of pad thickness,diameter and shape on current density and temperate distributions were investigated respectively.It was found that pads with larger thickness or/and diameter could reduce current density and temperature in solder bump significantly.Pad shapes affected the current density and temperature distributions in solder bumps.The relatively low current density and temperature didn＇t occur in the bump joint with traditional rounded pad but occurred in bump joints with octagonal and nonagonal pads respectively.Therefore,optimized pad geometry may be designed to alleviate the current crowding effect and reduce the bump temperature,and therefore delay electromigration failure and increase the mean-time-to-failure.

Correlation between current intensity and effective duration in the treatment of botulinus toxin for cerebral palsy by myoelectricity locating

BACKGROUND： Researches prove that the treatment of cerebral palsy by botulinus toxin （BTX-A） can improve effect and prolong effective duration. Current intensity is the important factor during injection. OBJECTIVE： To observe the changes of motor function and muscular intensity of children with spastic cerebral palsy after injecting BTX-A and analyze correlation between current intensity and effective duration. DESIGN： Cases control trial before and after nerves block SETTING： Capital University of Medical Sciences, China Rehabilitation Research Center PARTICIPANTS： From June 2002 to November 2004, 14 children with spastic cerebral palsy were treated by BTX-A block. All children were hospitalized in the Children Rehabilitation Department of China Rehabilitation Research Center. The children included 9 male and 5 female, and ranged from 4 to 13 years old, and average age was （6±2） years. Muscular tension ranged from grade 1 to grade 3. The diagnosis and the tape of cerebral palsy based on standard of the Fist Nationwide Cerebral Palsy Symposium, and all children were diagnosed with electroencephalogram （EEG）, CT and MRI, and permitted by their guardians. METHODS： （1） Locating and calculation： To locate block points by G6805-2A electro-therapeutic apparatus （Shanghai Huayi Electronic Instrument Plant） at the least stimulating current （continuous wave; impulse frequency; 2.667-83.333 Hz; current intensity： 0-6 mA; voltage： 6 V） to touch off muscles contraction. The current intensity of each point was recorded, and the average current intensity of each patient was calculated at the same time. （2） Dose of BTX-A： Basing upon the spastic degree and weight of patients, the dose was made certain： dose （IU）=（scores of Modified Ashworth Scale ＋2.5） xweight （kg）. The number of the block points was in all 4. The dose of injection ranged from 50 IU to 160 IU with the average of （73.6＋25.8） IU. The BTX-A was made by Lanzhou Institute of Biological Products, and each bottle contains 100 IU BTX-A. Muscular tension was evaluated by Modified Ashworth Scale. The scale ranged from grade 0 to grade 4, and the scores were from 0 to 4. The higher the scores were, the higher the muscular tension was. （3） Effect： Changes of muscular tension were evaluated by modified Ashworth Scale before and after block. Motor function was evaluated by Physician Rating Scale （PRS） before and after treatment. It contained Gait pattern, Hindfoot （ankle） position （stance-floor contact）, Hindfoot position （foot strike）, Knee position （degree of recurvation）, Crouch and Speed of gait. The scores ranged from 0 to 14. The higher the points were, the better the motor function was. （4） Effective duration： The duration was definited by the recovering of the Modified Ashworth Scale. （5） Statistic analysis： Firstly, the current intensity and the effect duration were analyzed by One-Sample Kolmogorov-Smirnov Test, the current intensity： Z= 0.456, P= 0.985, the effective duration： Z= 0.557, P= 0.915. Both data were normal distribution. Secondly, both data were analyzed by Linear Regression. The efficiency of the BTX-A block was analyzed by paired-samples t test. MAIN OUTCOME MEASURES： （1） Changes of motor function of muscular tension; （2） correlation between current intensity and effective duration. RESULTS： Fourteen children with spastic cerebral palsy were all involved in the final analysis. （1） Therapeutic effect： The average score of Ashworth scale after block was lower than that before block [（1.02±0.34） points vs. （2.12±0.48） points, t= 3.644, P〈 0.01]. The average score of RPS after block was higherthan that before block [（9.75±2.78） points vs. （6.16±0.58） points, t =13.222, P〈 0.01]. （2） Relation between the current intensity and the effective duration： The current intensity was （0.1857±0.0506） mA, and the effective duration was （26.36±4.48） weeks. The current intensity was negative correlation with effective duration （r = -0.775, P = 0.01 ）. CONCLUSION： （1） BTX-A occlusion can decrease muscular tension and improve motor function of lower limbs of children with spastic cerebral palsy. （2） The lower the current intensity is, the longer the effective duration is.

Charge Exchange Effect on Space-Charge-Limited Current Densities in Ion Diode

The article theoretically studied the charge-exchange effects on space charge limitedelectron and ion current densities of non-relativistic one-dimensional slab ion diode, and comparedwith those of without charge exchange.

Effect of Wave Accessibility on Lower Hybrid Wave Current Drive in Experimental Advanced Superconductor Tokamak with H-Mode Operation

The effect of the wave accessibility condition on the lower hybrid cm＇rent drive in the experimental advanced superconductor Tokamak （EAST） plasma with H-mode operation is studied. Based on a simplified model, a mode conversion layer of the lower hybrid wave between the fast wave branch and the slow wave branch is proved to exist in the plasma periphery for typical EAST H-mode parameters. Under the framework of the lower hybrid wave simulation code （LSC）, the wave ray trajectory and the associated current drive are calculated numerically. The results show that the wave accessibility condition plays an important role on the lower hybrid current drive in EAST plasma. For wave rays with parallel refractive index n｜｜= 2.1 or n｜｜ = 2.5 launched from the outside midplane, the wave rays may penetrate the core plasma due to the toroida] geometry effect, while numerous reflections of the wave ray trajectories in the plasma periphery occur. However, low current drive efficiency is obtained. Meanwhile, the wave accessibility condition is improved if a higher confined magnetic field is applied. The simulation results show that for plasma parameters under present EAST H-mode operation, a significant lower hybrid wave current drive could be obtained for the wave spectrum with peak value n｜｜ = 2.1 if a toroidal magnetic field BT =2.5 T is applied.

EFFECT OF DIFFERENT WAVEFORM'S ALTERNATING CURRENT ON THE INCISION'S SENSITIVITY

Compared with the conventionally used i=iosinωt alternating current, using asymmetric triangular and pulse wave as input signals can greatly enhance the incision's sensitivity of 'dE/dt-E'oscillogram.

A Modified Lattice Model of the Reversible Effect of Axial Strain on the Critical Current of Polycrystalline REBa2Cu3O7-δ Films

The strain effect on the critical current is one of the most important properties for polycrystalline YBa2 Cu3O7-δ （REBCO, RE： rare earth） films, in which the reversible effect is intrinsic in the range of strain 0 and the irreversible strain εirr. By introducing the applied strain, a modified grain boundaries （GBs） in the REBCO film is developed. lattice model combining the strain and misorientation of A good agreement of the calculation on the lattice model with the experimental data shows that the lattice model is able to well describe the reversible effect of axial strain on the critical current of the REBCO film, and provides a good understanding of the mechanism of the reversible effect of the strain. Moreover, the effects of the crystallographic texture of the REBCO film and the residual strain εr on the variation of the critical current with the applied strain are extensively investigated. Furthermore by using the developed lattice model, the irreversible strain εirr of the REBCO film can be theoretically determined by comparing the calculation of the critical current-strain curve with the experimental data.

Abnormality of thermal structure and current in the upper western tropical Pacific Ocean and its effect on subtropical high

-Mainly on the basis of the data obtained during PRC/US bilateral TOGA cruises, abnormal variation occurred during the 1986/1987 El Nino is shown in this paper about the thermal structure and circulation of the upper western tropical Pacific Ocean. The effects of the abmormal variation on the subtropical high over the Northwest Pacific Ocean are discussed. During the El Nino: (1) In the east part of the western tropical Pacific Ocean (the subsurface temperature data on the 165° E section are taken as an example), the water wanner than 29 C in the upper layer spread on the longitudinal section and positive temperature anormalies appeared in a large area of the sea surface. (2) In the west part of the western tropical Pacific Ocean (the subsurface temperature data on the 137°E section are representative ), the cross section occupied by the upper layer warmer water ( T >28 ℃ ) became shrunk, and the sea surface temperature showed negative amomalies. (3) The eastward flows in the upper layer of the 165°E section strengthened. (4)The northward flow volume of warm water from the origin area of Kuroshio, i. e. , the tropical oceanic area south of 18?0' N and from the west of 130?E to the Philippine coast, decreased. When those kinds of abnomal variation occurred, air divergence on the low level (1 000 hPa) over the Northwest Pacific Ocean was intensified, favourable to the strengthening of subtropical high over the Northwest Pacific Ocean.

MHz cut-off frequency and permeability mechanism of iron-based soft magnetic composites

The lack of soft magnetic composites with high power density in MHz frequency range has become an obstacle in the efficient operation of the electrical and electronic equipments.Here,a promising method to increase the cut-off frequency of iron-based soft magnetic composites to hundreds of MHz is reported.The cut-off frequency is increased from 10 MHz to 1 GHz by modulating the height of the ring,the distribution of particles,and the particle size.The mechanism of cut-off frequency and permeability is the coherent rotation of domain modulated by inhomogeneous field due to the eddy current effect.An empirical formula for the cut-off frequency in a magnetic ring composed of iron-based particles is established from experimental data.This work provides an effective approach to fabricate soft magnetic composites with a cut-off frequency in hundreds of MHz.

PREDICTION OF MAXIMUM SCOUR DEPTH AROUND LARGE DIAMETER CYLINDER UNDER THE EFFECTS OF BOTH WAVE AND CURRENT

Physical model tests were counducted to predict local scour and maximum scour depth around the large diameter cylinders located in the (sand) seabed under the action of both wave and current . According to the result of tests, an analysis was made on all the factors influencing the scour. The results shows that for the seabed with relative fine grains in shallow water (0.07<h/L≤0.28),when the relative diameter D/L of the cylinder is within 0.3 0.7,the main effective scour factors around the cylinder in the seabed are diameter D of the cylinder, the wave height H, the wave length L, the velocity V c of the current and the parameters related to the seabed soil texture. The main parameters influecing the maximum scour depth were analyzed, and the test data were syntherized, to obtain the formula predicting the scour depth around the large diameter cylinder under the of both wave and current.

Design and first result of combined Langmuir-magnetic probe on J-TEXT tokamak

In order to measure boundary electrostatic and magnetic fluctuations simultaneously,a combined Langmuir-magnetic probe(CLMP)has been designed and built on joint-Texas experimental tokamak.The probe consists of 8 graphite probe pins and a 3D magnetic probe,driven by a mechanical pneumatic device.By means of simulation,the shielding effect of the graphite sleeve on the magnetic fluctuation signal is explored,and the influence of the eddy current was reduced by cutting the graphite sleeve.In the experiment,it has been verified that the mutual inductance of electromagnetic signals can be ignored,and a 70–90 k Hz electromagnetic mode is observed around the last closed magnetic surface.The establishment of CLMP provides data for the exploration of the coupling of electrostatic and magnetic fluctuations.

Study of Magnetic Force Distribution for Electromagnetic V-shape Bending Forming of Small Size Flat Sheet

Electromagnetic V-shape bending of small size sheet blank is investigated numerically and experimentally. Three-dimensional electromagnetic field models are established to calculate the magnetic force distribution on the sheet by software ANSYS / EMAG. Series of electromagnetic V-shape bending forming experiments are presented,in which small size uniform pressure coil and big size round flat spiral coil are used. The results show that small size uniform pressure coil is not suitable for electromagnetic forming of small size flat sheet,and the coil is susceptible to failure such as bulging,ablation and cracking. When the plane dimension of round flat spiral coil is bigger than sheet blank sizes,the induced current crowding effect will be resulted which seriously influence the magnetic force distribution on the sheet. In this case,magnetic force distribution can be adjusted through the change of the relative position between coil and sheet,the desired deformation can be obtained finally. Therefore,big size round flat spiral coil can be well applied to electromagnetic V-shape bending forming of small size flat sheet.