Syntheses of Spinon Thermal Conductivity Materials in Sr–Cu–O System by Glass‐Ceramics Technique

We have synthesized spinon thermal conductivity materials in Sr–Cu–O system by glass‐ceramics technique. The materials are promising for active control of thermal energy in microelectronic devices because of high and anisotropic thermal conduction, its controllability, and electric insulation. Nevertheless, research on these materials has been limited to that concerning theoretical perspectives and investigation of physical properties using large single crystals. In this study, we adopt glass‐ceramics technique to synthesize these materials: We prepared melt‐quenched multicomponent oxides including SrO and CuO, and checked its glass‐forming ability and crystallization behaviors by heating. As a result, we have found that SrCuO₂ and Sr₁₄Cu₂₄O₄₁, known as the spinon thermal conductivity materials, are synthesized using SrO–CuO–?Li₂O–?Al₂O₃?–Ga₂O₃ system. This synthesis process for the system will provide practical application of the spinon thermal conductivity materials.     

Lateral Inhomogeneity in the Electronic Structure of a Conjugated Poly(3‐hexylthiophene) Thin Film

How annealing influences the morphology of a highly regioregular poly(3‐hexylthiophene) (RR‐P3HT) film at the substrate interface as well as the lateral inhomogeneity in the electronic structure of the film are elucidated. Whereas previous studies have reported that high‐molecular‐weight (MW) RR‐P3HT films tend to show low crystallinity even after annealing, it is found that high‐MW RR‐P3HT does show high crystallinity after annealing at high temperature for a long time. Photoemission electron microscopy (PEEM), X‐ray photoemission spectroscopy, and ultraviolet photoemission spectroscopy results clearly resolve a considerable lateral inhomogeneity in the morphology of RR‐P3HT film, which results in a variation of the electronic structure depending on the local crystallinity. The PEEM results show how annealing facilitates crystal growth in a high‐MW RR‐P3HT film.     

Using two ray multipath model for microwave link budget analysis

A two-ray ground multipath deterministic model for worst-case fading-depth prediction in microwave link budget analysis is presented. Simple formulas, providing insight into fading depth as a function of geometrical and electrical parameters, are derived. A detailed analysis shows that, in many cases, the fading depth depends mainly on the path-clearance angle. Comparison with the Olsen-Segal model shows that both models have roughly the same path-clearance-angle factor. To the best of the authors' knowledge, this can be considered the first theoretical justification of the path elevation factor in the Olsen-Segal model     

On the linearity and efficiency of outphasing microwave amplifiers

A new approach for the analysis of the efficiency and linearity of Chireix-outphasing combiners is presented. The approach takes into account, in an explicit manner, the effect of impedance mismatch between the amplifiers and the lossless combining structure. It is shown that the impedance mismatch leads to new expressions for the output voltages from both branches of the amplifier. These expressions explain the origin of the lack of linearity reported in the literature for the Chireix architecture and lead to a new expression for the instantaneous efficiency of a Chireix combiner. Various simulations using a commercial simulator are performed and their results are compared to those predicted by the derived equations. A quasi-exact agreement between the simulator and derived equations is found for all simulations conducted, including voltage expressions, linearity analysis, and instantaneous and average efficiency calculations for a code-division multiple-access signal. The impact of combiner parameters on its linearity and efficiency is also studied.     

A CAD-suitable approach for the analysis of nonuniform MMIC andMHMIC transmission lines

A new method of moment-based formulation for the solution of the telegraphist's equations in nonuniform transmission lines is presented. Entire domain basis functions that build in a frequency variation are used to cover wider frequency and physical dimension ranges. The results obtained using the proposed formulation are validated by comparison to those obtained by a CAD package and to measured data. Different nonuniform lines in microstrip and coplanar technologies on monolithic microwave/millimeter wave integrated circuit (MMIC) and miniaturized hybrid microwave integrated circuit (MHMIC) substrates are investigated with an application to the design a matched taper transition in a MMIC coplanar line     

Induction of platelet-activating factor in mice by intravenous administration of a neutral fraction of bakers' yeast mannan

A neutral subfraction of mannan of bakers' yeast (WNM) was found to show a lethal effect in mice when administered intravenously. Symptoms caused by intravenous (i.v.) administration of WNM resembled those resulting from the administration of platelet-activating factor (PAF). CV-3988 and ONO-6240, selective PAF antagonists, prevented hypotension and death caused by the administration of WNM or PAF. A β-adrenoceptor agonist was shown to prevent death caused by WNM, whereas propranolol increased the lethal activity of WNM. Intravenous administration of WNM into mice produced PAF in gall bladder fluid which was determined by platelet aggregation assay. The findings indicate that WNM is able to induce PAF in mice and that the resultant PAF may participate in the WNM-induced lethal activity observed in mice.     

Sensorless Vector Control of Parallel-Connected Multiple Induction Motors Fed by a Single Inverter

KoukiMatsuse:Sensorlessvectorcontrolofparallel connectedmultipleinductionmotorsFedbyasingleinverter　　　InEq.(12) Φerand iesaredividedintode qeaxiscomponent,thenEq.(12)isexpressedby: T′=p M′{ ieqsedr- iedseqr Δ ieqsΔeqr-Δ iedsΔeqr}(17)     

Bending fracture rule for 3D-printed curved continuous-fiber composite

Three-dimensional (3D) printing is an attractive technology to produce complex structures without the need for expensive tools and molds. Additives are usually incorporated with the plastic materials used in 3D printing to increase their strength and rigidity. In particular, carbon fiber-reinforced plastic (CFRP) shows promise as a material for use in 3D printing. However, the strength of CFRP after printing is still unclear, although it is known that its strength is affected by the plastic melting during printing. In this study, we analyzed the fracture behavior of CFRP specimens before and after bending to different curvature radii. From the experimental results, a fracture criterion that described the behavior of the materials by considering tensile and compressive loads was developed. The fracture mechanism was the same for CFRP specimens with different curvature radii. These results increase our understanding of the mechanical properties of CFRP materials used in 3D printing.