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In this paper, we report on the magnetic properties and magnetocaloric effect (MCE) in NaZn13-type LaFe11.2Co0.7Si1.1Cx (x=0.1 and 0.3) close to room temperature. The Landau theory as well as the temperature dependence of magnetization data revealed that LaFe11.2Co0.7Si1.1C0.1 and LaFe11.2Co0.7Si1.1C0.3 exhibit a second-order magnetic transition near their Curie temperature. We have calculated the magnetocaloric effect both in terms of isothermal entropy change and adiabatic temperature change using the magnetization and the direct measurements. Under an external field change from 0 to 5 T, -ΔS is 14.5 J/kg K (TC=290 K) and 8 J/kg K (TC=310 K) for x=0.1 and 0.3, respectively. The calculated refrigerant capacity for a field change in 0-5 T is about 305 and 286 J/kg K, for LaFe11.2Co0.7Si1.1C0.1 and LaFe11.2Co0.7Si1.1C0.3respectively, which is larger than that of some magnetocaloric materials with a first-order phase transition (Gd5Ge2Si2). ΔTad decreases with increasing C content. It was found to be about 1.5 for x=0.1 and 1.2 for x=0.3 under 1.48 T. [ABSTRACT FROM AUTHOR]

Results on both field driven and current induced domain wall motion in Co/Cu/Ni80Fe20 trilayered half-ring in-series wires with different linewidths were presented. The switching behavior depends linearly on the linewidth of Co/Cu/Ni80Fe20 trilayered half-ring structures. A larger bias field (Hb) applied to the samples results in a smaller critical current needed to reverse magnetization. The critical current density was observed to be 3×107 A/cm2 for Ni80Fe20 and 2×108 A/cm2 for Co at zero field. The results of the numbers of giant magnetoresistance jump (digital) versus external magnetic field and current densities (analog) of this design have potential utility as an analog-digital converter. [ABSTRACT FROM AUTHOR]

Nickel/lead multilayered nanowires were prepared using standard three-electrode electrodeposition into anodic aluminum oxide porous templates. The diameters of the nanowires ranged from 50 to 200 nm. By means of electric and magnetic measurements, we found that the superconducting transition temperature, Tc, of the Pb layer persisted down to the smallest diameter without any noticeable dimensional effect. Tc was affected by the relative orientation of magnetizations in neighboring Ni layers. When the superconducting layers were driven normal under a large magnetic field, unusual resistance increase was observed with decreasing temperature, which was consistent with the Kondo effect. [ABSTRACT FROM AUTHOR]

Structural and magnetic properties of Ga0.93Mn0.07As layers grown on (001) and (311)A GaAs substrates by molecular-bean epitaxy are investigated. The as-grown (001) and (311)A Ga0.93Mn0.07As layers exhibit the same Curie temperature (TC) of 80 K. However, upon annealing, the TC’s of the (001) and (311)A Ga0.93Mn0.07As layers are enhanced by 80 and 60 K, respectively. X-ray diffraction studies reveal that the AsGa defects cannot be removed by low-temperature annealing, and a higher concentration of AsGa defects exist in the (311)A layers than in the (100) reference layers. The less enhancement in TC by annealing for the (311)A Ga0.93Mn0.07As layer can be ascribed to the larger amount of AsGa defects in the material. [ABSTRACT FROM AUTHOR]

The microstructure and magnetocaloric effect of the La0.8Ce0.2(Fe0.95Co0.05)11.8Si1.2 strip-cast flakes annealed between 1273K and 1423K for different time have been investigated. For the flakes annealed for 2h from 1273K to 1423K, the shape and distribution of α-Fe, La-rich and NaZn13-type 1:13 phases are quite sensitive to the annealing temperature. Especially, at a high annealing temperature of 1423K, the 1:13 phase began to decompose into macroscopic α-Fe conglomerations and La-rich dendrites. With the increase of annealing time from 0 to 12h at 1323K, the amount of 1:13 phase increased significantly and reached ∼93.50 wt.% at 12h. However, an overlong annealing time also led to 1:13 phase decomposition and influenced the magnetic performance. For the flakes annealed at 1323K for 12h, large magnetic entropy change value of 18.12Jkg-1K-1 at 5T has been obtained. The present results indicate that strip casting method can potentially be used in mass production of high performance magnetocaloric materials. [ABSTRACT FROM AUTHOR]

Objective: The G‐allele of the ‐1019C/G (rs6295) promoter polymorphism of the serotonin receptor 1A (HTR1A) gene has been implicated in anxiety; however, the underlying neurophysiological processes are still not fully understood. Recent evidence indicates that low parasympathetic (vagal) tone is predictive of anxiety. We thus conducted a structural equation model (SEM) to examine whether the HTR1A rs6295 variant can affect anxiety by altering parasympathetic nervous activity. Method: A sample of 1141 drug‐free healthy Han Chinese was recruited for HTR1A genotyping. Autonomic nervous function was assessed by short‐term spectral analysis of heart rate variability (HRV). Anxiety and stress levels were evaluated by the Beck Anxiety Inventory (BAI) and the Perceived Stress Scale (PSS) respectively. Results: The number of the HTR1A G allele was inversely correlated with high‐frequency power (HF), a parasympathetic index of HRV. The HF index was negatively associated with BAI scores. Furthermore, the good‐fitting SEM, adjusting for confounding variables (e.g., age and PSS levels), revealed a significant pathway linking rs6295 variant to BAI scores via HF index modulation. Conclusion: These results are the first to show that HTR1A ‐1019C/G polymorphism influences anxiety levels by modulating parasympathetic tone, providing a neurophysiological insight into the role of HTR1A in human anxiety. [ABSTRACT FROM AUTHOR]

To reveal the causes of unlawful behaviours between special equipment quality supervision institutions and third-party special equipment inspection institutions, an evolutionary game model was developed. Since the expected payoff matrix frequently used in general game model cannot accurately describe the influence of the risk expectations, the prospect value function was proposed to build the revenue perception matrix of the model. Then, the evolutionary characteristics were analysed through replicator dynamics equations. Accordingly, the evolutionary stable strategies were obtained based on the Jacobian matrix. Moreover, the dynamic evolution phase diagrams were formulated to describe the behaviours. Finally, numerical simulation examples were conducted to investigate the evolutionary path and the evolutionarily stable strategies. Results show that the probability of the third-party special equipment inspection institution choosing the passive performance strategy is negatively correlated with the expected risk value. The supervision probability of the quality supervision institution is directly proportional to the social benefits. In addition, the supervision probability is dependent on the penalty risks, and the initial population scale. [ABSTRACT FROM AUTHOR]

A spin transistor consisting of a metallic pseudo-spin-valve emitter, a copper base, and a p-n junction collector was prepared on a Si(100) wafer. This spin transistor can provide high magnetocurrent output, high magnetocurrent variation, and high transfer ratio. The common collector configuration with an emitter bias of 5.12 V at 77 K gives a large magnetocurrent variation of more than 95.5 μA in the collector, and the change is more than 3400% with a transfer ratio of 2.59310-3. At room temperature, these changes go down to 98.3 μA and 55.3%, respectively, and the transfer ratio rises to 5.98310-3. The high performance of this spin-valve transistor is due to the use of a p-n junction as an energy barrier to select spin electrons. [ABSTRACT FROM AUTHOR]

Two novel red phosphors KBaEu(XO4)3 (X = Mo, W) have been synthesized by high-temperature solid-state reactions and the crystal structures were determined for the first time. Single-crystal X-ray diffraction data reveal that their space groups are C2/c. The crystalline structure is constituted of K/BaO8 distorted square antiprisms and distorted EuO8 polyhedra which form chains lying along the c-axis and two kinds of distorted XO4 tetrahedra. This high disorder of K/Ba which might lower the crystal field symmetry around Eu3+ results in the high purity of red emission around 615 nm originating from 5D0→7F2 transition under near-ultraviolet (NUV) excitation. With increasing temperature, the luminescence of KBaEu(XO4)3 (X = Mo, W) phosphors decreases almost linearly with subtle alteration for the CIE coordinate. As the temperature reaches 550 K, the red emission intensity decreases to 37.3% and 50.7% of that at 300 K for KBaEu(MoO4)3 and KBaEu(WO4)3, respectively. The analysis of the decay curves of the 5D0→7F2 emission at variable temperatures indicates the weak cross relaxation and non-radiative energy transfer between Eu3+ ions. These results demonstrate that the investigated phosphors are attractive for application in high power NUV excited white LEDs. [ABSTRACT FROM AUTHOR]

With a large growth potential, manufacturing of microphones with least rejection becomes inevitable. A case study was conducted to investigate the possible causes of microphone rejection. The polarization voltage developed on the microphone diaphragm has a direct effect on the microphone sensitivity. Hence, variation in the polarization voltage was investigated. Initial studies were conducted with an arrangement of fixture plate (bearing holes for holding microphones) that was placed on 2 base (support) plates. The investigations were carried out for 23 microphone positions across 11 readings. The acceptable and non-acceptable polarization voltages were earmarked (designated) and failure percentage was determined. Further, one base plate was removed to increase the distance between top electrode and diaphragm and polarization voltage was measured. The result showed an appreciable reduction in the polarization voltage that indicated a promising reduction in the microphone failure. For a representative electret condenser microphone, a non-linear variation between sensitivity and polarization voltage was established. Statistical analysis revealed that measurement data is symmetric and distributed normally. The proposed modification when implemented on the shop floor reduced rejection from 33% to 16%. [ABSTRACT FROM AUTHOR]