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Parametric pumping is a nonlinear wave phenomenon and a promising technique for electronic devices based on spin waves, so-called “magnonics”. For parametric excitation, a magnetic nanowire system that has a built-in dc current line to produce an Oersted field is designed, and for spin wave detection, a micro-Brillouin light scattering (μ-BLS) system is used. A spin wave with a frequency of fsw = 5.6 GHz is observed when a pumping microwave with a frequency of fmw = 11.2 GHz is applied. The wave is found to be of the n = 1 width mode (n is the antinode number), and its mode changes to an edge-localized (or possibly n > 1) mode when the Oersted field (or current) varies. Joule heating effects are not observed in the pumping process. Thus, spin wave mode control by the built-in current would be a convenient and useful method to enhance the efficiency and compatibility in applications of spin-based electronics.

In the development of spin-based electronic devices, a particular challenge is the manipulation of the magnetic state with high speed and low power consumption. Although research has focused on the current-induced spin-orbit torque based on strong spin-orbit coupling, the charge-based and the torque-driven devices have fundamental limitations: Joule heating, phase mismatching and overshooting. In this work, we investigate numerically and theoretically alternative switching scenario of antiferromagnetic insulator in one-dimensional confined nanowire sandwiched with two electrodes. As the electric field could break inversion symmetry and induce Dzyaloshinskii-Moriya interaction and pseudo-dipole anisotropy, the resulting spiral texture takes symmetric or antisymmetric configuration due to additional coupling with the crystalline anisotropy. Therefore, by competing two spiral states, we show that the magnetization reversal of antiferromagnets is realized, which is valid in ferromagnetic counterpart. Our finding provides promising opportunities to realize the rapid and energy-efficient electrical manipulation of magnetization for future spin-based electronic devices., Comment: 19 pages, 5 figures

The effects of the reduction ratio (RR) on the low-cycle fatigue (LCF) properties of the Zn-22 wt.% Al (Zn-22Al) alloy were investigated. Various grain sizes from 0.68 to 1.13 μm were obtained by controlled RRs. Tensile and LCF tests were carried out at room temperature. Superplasticity and cyclic softening were observed. Strength and ductility of the rolled Zn-22Al alloy increased with the RR, owing to the decrease in its grain size. The RR did not affect the cyclic softening behavior of the alloy. The fatigue life of the alloy decreased with increasing strain amplitude, while the fatigue life first decreased and then increased with increasing RR. The longest fatigue life was observed for the alloy rolled at a RR of 60%. A bilinear Coffin-Manson relationship was observed to hold true for this alloy.

A GSK3/shaggy-like kinase (AtGSK1) has been implicated in the regulation of drought and salt tolerance. We transferred AtGSK1 from Arabidopsis thaliana to a hybrid poplar (Populus alba × P. tremula var. grandulosa) to determine the effect of the transgene expression in the transgenic trees. The results from northern blot and RT-PCR analyses showed that the expression level varied among the transgenic lines. During their culture on tissue culture media, the transgenic poplars formed vigorous growing roots even in the presence of 125 mM NaCl and callus in the presence of 150 mM NaCl. When the transgenic poplars were growing in pots and provided with NaCl solution, they stayed much healthier than did nontransgenic poplars, showing higher rates of photosynthetic rates, stomatal conductance, and evaporation rates under the stress. Whereas the total level of leaf Na+ level increased dramatically in transgenic poplars under severe saline conditions (150 mM NaCl), that of leaf K+ decreased in the same plants under the same conditions. Total root Na+ level increased in nontransgenic poplars under severe saline conditions. In contrast, total root K+ level decreased in the same plants under the same conditions. The chloride content and relative electrical conductivity of the transgenic poplars after salt stress treatment were lower than those of nontransgenic poplars. The transgenic poplars were also tolerant to up to 20 % PEG remaining significantly healthy when compared with nontransgenic poplars with necrosis and chlorosis symptoms. Another dramatic feature of the transgenic poplars was wilting tolerance for prolonged drought treatment up to 2 weeks. The results provide evidence that the expression of AtGSK1 gene conferred drought and salt tolerance in the transgenic poplars.

Spectroscopic ellipsometry measurements are performed on thin pentacene films grown on glass, SiO2, and n-Si substrates. The Gauss–Lorentz oscillator model is shown to be effective in modeling the π–π∗ transitions found in organic compounds. The effective medium approximation that considers the surface roughness of the films, which can be significant in case of pentacene, is also shown to be a key factor in precisely determining their dielectric functions. The proposed method reveals that there are some quantitative differences in the optical properties of the pentacene films prepared on different substrates.

New aromatic diamine containing preformed amide, ether, and methylene; bis-[(4′-aminobenzyl)-4-benzamide] ether (BABE), was synthesized and characterized by FT-IR, NMR, and mass spectrometry. Aromatic–aliphatic polyamides were prepared from BABE with aliphatic/aromatic diacids via Yamazaki’s polymerization. The polyamides were characterized by FT-IR, 1H NMR, inherent viscosity [ηinh], solubility tests, differential scanning calorimetry [DSC], thermogravimetric analysis [TGA], and X-ray diffraction [XRD]. Polyamides had inherent viscosities 0.35–0.84 dL/g, soluble in aprotic polar solvents like N-methyl-2-pyrrolidone, N, N-dimethyl acetamide and dimethyl sulphoxide containing LiCl due to an amorphous to partially crystalline morphology; as XRD patterns indicated. DSC analysis of polyamides showed glass transition temperatures 166–268 °C. Polyamides showed high thermal stability as they did not degrade below 300 °C, had 10% weight loss temperature higher than 375 °C, and the char yields at 900 °C were 22–55%; indicating potential applications as engineering materials.

The manufacture of rheology materials from wrought and casting aluminum alloys using controlling solid fraction and crystal grain is demonstrated in this paper. The equipment to form the rheology material was designed so that shear force and applied pressure could be carefully and simultaneously applied using a mechanical stirrer. The problems caused by using this method with the thixo forging process were studied by investigating the mechanical properties of a sample that had a controlled solid fraction of 45-50 %.

Up to now, the value of the dynamic critical exponent z is still an open question. We have studied this exponent in the intermediate (XY) critical regime in zero field for a set of high quality Bi2Sr2CaCu2O8+delta single crystals both by previously obtained critical exponents of the de critical conductivity fluctuations [1] and in terms of Fisher-Fisher-Huse (FFH) dynamic scaling [2]. In this regime (i.e. the absence of Coulomb interactions), one would expect model-E dynamics (z = 1.5) to apply with the conserved charge-density conjugate to the phase fluctuations. However, we find the dynamic critical exponent to be z = 2, which is in agreement with the suggestion of FFH that due to the plasma fluctuation, fully relaxational dynamics, model A (z = 2), should be appropriate.

to C1v by the photo-isomerization process, with the azobenzene conformation retained as trans-isomer.

A previous study on the minimum cost design of multispan partially prestressed concrete (PPC) beams using DCOC is extended to multispan T-beams. The cost of construction which includes the costs of concrete, prestressing steel, nonprestressing steel and formwork is minimized. The design constraints include limits on the maximum deflection, flexural and shear strengths, in addition to ductility requirements, and upper and lower bounds on design variables as stipulated by the Australian Code AS 3600. Based on Kuhn-Tucker necessary conditions, the optimality criteria are explicitly derived in terms of the design variables-effective depth, eccentricity of prestressing steel and non-prestressing steel ratio. The prestressing profile is prescribed by parabolic functions. The self-weight of the structure is included in the equilibrium equation of the real system, as is the secondary effect resulting from the prestressing force. An iterative procedure for updating the design variables is outlined. Two numerical examples of multispan PPC beams with T crosssection are solved to show the applicability and efficiency of the DCOC-based technique.

The electrical activity of phosphorus in Si80Ge20alloys prepared by two nonconventional doping processes has been investigated over the temperature range 25–1250 °C. Both a solid state (mechanical alloying) and gaseous phase doping processes were found to extend the electrical activity of phosphorus in Si80Ge20alloys beyond the reported maximum equilibrium value (2.1 × 1020/cm3) to 2.5–2.9 × 1020/cm3within the temperature range 900 1200 °C. It is likely that this extended electrical activity of phosphorous is associated with a high density of defects. The enhanced electrical activity of phosphorus enabled Si80Ge20alloys to have 300 to 1000 °C integrated average electrical power factors in the range 30.1–35.7 μW/cm-°C2.

Various spots in GaAs, In-diffused with the 1.064 μm line of pulsed Nd:YAG laser with several energy densities, have been characterized and compared with samples prepared by the conventional rapid thermal annealing method. Of the energy densities used, the spot processed with an energy density of 7 J/cm2 shows InxGa1−xAs phases with an indium concentration of 60% and below. An abrupt boundary in the indium concentration is observed at the edge of the laser-annealed spot. The diffusion depth is found to be less than 1000 A. The spot processed with an energy density of 14 J/cm2 shows considerable damage from the irradiation resulting in strain in the lattice. The samples prepared by the thermal annealing method show similar results to the laser-diffused samples. However, these thermally annealed samples suffer from arsenic loss unlike the laser-processed samples. It can be concluded that laser-induced alloying of indium into GaAs can be achieved with less arsenic loss than the thermal annealing method.

Investigations of Y1−x M x Ba2Cu3O7−δ (M=Ce, Th)c-axis oriented thin film specimens show that the rate of depression ofT c withx is larger for M=Th, than for M=Ce and Pr, and suggest that Ce, like Th, is tetravalent in this compound. Hall effect measurements on Y1−x Pr x Ba2Cu3O7−δ single crystals reveal aT 2 dependence of the cotangent of the Hall angle in the normal state and a “negative Hall anomaly” belowT c in the superconducting state, in agreement with recent reports. Our research shows that the depth, Δ, of the negative Hall signal scales withT/T c and that the maximum value of Δ decreases linearly withx and vanishes atx≈0.24. Magnetoresistance measurements on Y1−x Pr x Ba2Cu3O7−δ single crystals indicate that the irreversibility lineH(T *) obeys a universal scaling relation characterized by anm=3/2 power law nearT c, with a crossover to a more rapid temperature dependence of belowT/T c ≈0.6, similar to that observed for polycrystalline specimens.

The objective of this paper is to provide a method of optimizing areas of the members as well as the shape of both two-hinged and fixed arches. The design process includes satisfaction of combined stress constraints under the assumption that the arch ribs can be approximated by a finite number of straight members. In order to reduce the number of detailed finite element analyses, the Force Approximization Method is used. A finite element analysis of the initial structure is performed and the gradients of the member end forces (axial, bending moment) are calculated with respect to the areas and nodal coordinates. The gradients are used to form an approximate structural analysis based on first order Taylor series expansions of the member end forces. Using move limits, a numerical optimizer minimizes the volume of the arch with information from the approximate structural analysis. Numerical examples are presented to demonstrate the efficiency and reliablity of the proposed method for shape optimization. It is shown that the number of finite element analysis is minimal and the procedure provides a highly efficient method of arch shape optimization.

Anomalies of the carotid artery are rare in clinical experience. To our knowledge a tortuous common carotid artery with an abnormal course encountered during neck dissection has never been reported in the available world literature. During dissection of the lower neck in a 60-year-old Korean man, a tortuous right common carotid artery was found to cross over the lower cervical trachea anteriorly and then was positioned in its usual site in the carotid sheath in the mid-neck.

We report on the systematic study of the evolution of the in-plane (ρab) and out-of-plane (ρc) resistivities of fully oxygenatedY1−xPrxBa2Cu3O7−δ single crystals. ρc(x) exhibits a non-monotonic behavior: at low to moderatex, ρc(x) and the anisotropy ρc(x) increase, reaching a maximum at x≈0.42; for higherx,x, ρc and ρc/ρcab decrease, while ρab continues to increase monotonically. These results, along with the coexistence of metallic ρab(T) and semiconducting ρc(T), are consistent with the presence of a gap in the energy spectrum of the chains, leading to tunneling through both valence and conduction bands of theCuO chains.

We observed the development of a resistive anomaly in the magnetic fieldH and temperatureT dependences of the electrical resistivity ρ of polycrystalline CeRu2. The transition into this resistive region, which is observed in the superconducting state well below the upper critical fieldH c2(T), is hysteretic in bothT andH. The intermediate field interval where ρ=0 corresponds to the field region in which an irreversible anomaly is observed in the magnetization curvesM(H). In some regions of theH-T plane, the resistivity exhibits transient behavior that could be due to flux jumps. The anomaly is very sensitive to the transport current density and appears to be due to a decrease and subsequent increase of fluxoid pinning asH c2(T) is approached from within the mixed state.

Cubitermes fungifaber, a humus-feeding termite from the forest of the Ivory Coast, builds an earthen nest by successive additions. When the nest is experimentally damaged, the surviving colony frequently migrates some distance away, by a subterranean route, and builds a new nest. This relocation sometimes occurs without any noticeable previous disturbance. We present evidence of the frequent occurrence of such relocations, which could be normal events during the development of the society.

The influence of the reproductives on soldier production was studied in two species of higher termites,Nasutitermes lujae (Nasutitermitinae) andCubitermes fungifaber (Termitinae). In both species, the royal pair has a stimulatory influence on soldier production. The soldier molts are two to three times more numerous when workers are reared with the reproductives. InN. lujae, the king and the queen have an apparently equal stimulatory influence. The reproductives act on both induction and orientation of the molts toward the soldier type. It can be now claimed that inN. lujae, in which the existence of an inhibitory soldier pheromone was recently evidenced, the proportion of soldiers results from the balance between the stimulatory influences of the reproductives and the inhibitory influences of the soldiers. The hypothetical nature of the royal stimulatory influence is discussed.