Frenkel pair accumulation induced crystallization of amorphous MgAl2O4

The epitaxial and homogeneous irradiation induced re-crystallization of amorphous MgAl₂O₄ was studied by means of continuous Frenkel pair accumulation in the molecular dynamics framework. Present results point out that the re-crystallization induced by Frenkel pair accumulation appears in both cases to be thermally enhanced but non diffusive. It is governed by a local rearrangement of each point defect in the homogeneous case, while spontaneous Frenkel pair recombination process in the crystalline part or at the interface drives the re-crystallization in the epitaxial case.     

Smoking and small, dense low-density lipoprotein particles: cross-sectional study

All forms of tobacco cause cardiovascular disease, and tobacco-related disease is a leading cause of death worldwide. Smoking oxidizes low-density lipoprotein (LDL) particles, and oxidized LDL particles are thought to play an early and critical role in atherosclerogenesis. Hyper-low-density lipoproteinemia is one of the risk factors for cardiovascular disease, but small, dense LDL particles have been associated with an increased risk for cardiovascular disease. Small, dense LDL correlates with some cardiovascular risk factors such as diabetes mellitus, hypertriglyceridemia, hypo-high-density lipoproteinemia, and hypertension. Although smoking is also a major risk factor for cardiovascular disease, the relationship between smoking and small, dense LDL particles has not been described previously. Our cross-sectional study examined this relationship in a population of 18 healthy young adult men (9 smokers and 9 never-smokers, aged 21-24 years) from the same college. Concentrations of blood lipids and the LDL migration index (LDL-MI) were examined. Although concentrations of blood lipids did not differ between smokers and never-smokers, the LDL-MI had a strong tendency to be lower in smokers. The LDL-MI is larger in the presence of a greater proportion of small, dense LDL particles. These results indicate that tobacco smoking is associated with a decrease in the proportion of small, dense LDL particles. Regardless of these surprising results, we do not recommend smoking, given that it is a major cause of cardiovascular disease.     

Orbit systematics in anisotropic Kepler problem

We revisit the Anisotropic Kepler Problem (AKP), which concerns with trajectories of an electron with anisotropic mass term in a Coulomb field. This is one of the most fundamental fields in Quantum Chaos. Nowadays various quantum systems are challenging us. Classical theories of these may have chaos. Quantum mechanics have developed from integrable cases and may have to be reformulated for such cases. AKP then serves as a suitable testing ground for quantum chaos. We first review a pioneering work by Martin Gutzwiller (J Math Phys (1977) 18:106). We shall show the systematics of the trajectories using ample figures from an extensive numerical analysis. Then we focus on the rolê of hyperbolic singularities and we comment on the approximations in an analytic formulation. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Lagrangian method for deriving electrically dual power converters applicable to nonplanar circuit topologies

This paper proposes a novel method for deriving dual converters, namely deriving current‐source converters from voltage‐source counterparts, and vice versa. The conventional derivation method is based on the transformation of circuit topology, in which series connections are converted into parallel connections, and vice versa. However, this method cannot be directly applied to nonplanar circuits because they do not allow perfect topological transformation, although many of them are known to have duals. Lagrangian dynamics does not depend on the topological relation to transform a system into another equivalent system; therefore, it possibly avoids problems related to topological transformation and may provide a universal and systematic method that can be consistently applied to nonplanar circuits. This paper discusses the derivation of duals using Lagrangian dynamics. Along with the theory, this paper presents two examples of Lagrangian derivation of duals. One derives a dual of a planar circuit, to which the topological transformation is applicable. The other derives two duals of a nonplanar circuit. Consequently, these examples suggest that the proposed method is a prospective candidate for universal and systematic derivation of duals. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

工艺参数及稳定剂抗坏血酸对电沉积NiFeW合金的影响

为获得性能良好的镍铁钨合金镀层,研究了镀液pH 值、温度、电流密度、稳定剂抗坏血酸浓度对镍铁钨合金镀层成分和镀层沉积速率、显微硬度的影响。结果表明: 镀液pH 值对镀层W含量和镀层沉积速率影响较大;镀液温度对镀层沉积速率、镀层成分和镀层硬度影响均较大;随抗坏血酸浓度增加,镀层沉积速率逐渐降低,镀层表面形貌更加粗糙。在镀液pH = 4,温度60 ℃,电流密度4 A/dm2,抗坏血酸浓度3 g /L 时,镀层沉积速率和镀层的显微硬度较高,表面光亮致密,耐蚀性好。     

采用无偏振片反射式LCD及超低功耗驱动技术制造移动显示器件

我们通过对材料和制备条件的精细化处理,生产出一种在低刷新频率下无闪烁和图像迟滞现象的反射式显示器。该显示器的功耗非常低,且可在宽温度范围内工作,是未来移动显示器件的潜力平台。     

RETRACTED ARTICLE: Single-Phase <Emphasis Type="Italic">β</Emphasis>-Zn<Subscript>4</Subscript>Sb<Subscript>3</Subscript> Prepared by a Mechanical Grinding Method

Single-phase β-Zn₄Sb₃ materials were prepared by mechanical grinding (MG). Source materials for the Zn₄Sb₃ ingots were prepared using three different processes after the direct melting of constituent elements. In process 1, the ingot was obtained by quenching the melt in water within an evacuated quartz ampoule. In process 2, the ingot was heat-treated for 100 h at 723 K after process 1. In process 3, the ingot was heat-treated for a total of 200 h in two stages at 723 K and 673 K after process 1. The resultant ingots were mechanically ground and sintered at 623 K by hot pressing. The sintered materials were characterized by x-ray diffraction, differential thermal analysis (DTA), and thermoelectric property measurements. The thermal conductivity of the sintered materials was 0.88 W m⁻¹ K⁻¹ at room temperature, being slightly lower than that reported for the materials prepared by a conventional method. Results indicate that the dimensionless figure of merit of the single-phase β-Zn₄Sb₃ ranged from 1.06 to 1.31 at 573 K.     

Application of microalgae hydrolysate as a fermentation medium for microbial production of 2-pyrone 4,6-dicarboxylic acid

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The effect of the N-linked glycans on structural features and physicochemical functions of soybean β-conglycinin homotrimers

β-Conglycinin is a trimeric protein consisting of three subunits, α,α′,and β, which are N-glycosylated. The α and α′ subunits contain extension regions in addition to core regions common to all subunits. We purified homogeneous trimers consisting of only α, α′, or β from mutant soybean cultivars containing β-conglycinin lacking one or two subunits: α homotrimers from an α′-lacking mutant, α′ homotrimers from an α-lacking mutant, and β homotrimers from an α-and α′-lacking mutant. Structural features and physicochemical functions of the three homotrimers were examined and compared with those of recombinant homotrimers having no N-linked glycans. The native homotrimers have secondary structures very similar to those of the recombinant ones. In analogy with the recombinant homotrimers, the native ones exhibit different thermal stabilities from one another (β>α′>α), and the native α and α′ homotrimers exhibit better solubility, emulsifying ability, and heat-induced association than the native β homotrimer. Further, the N-linked glycans contribute to solubilities of the three subunits at low ionic strength (μ=0.08) and to the emulsifying ability of the native β homotrimer. N-Linked glycans also prevent heat-induced associations of the native α and α′ homotrimers but do not contribute to the secondary structure and the thermal stability of β-conglycinin.     

Influence of temperature on the fatigue strength of compressed-hydrogen tanks for vehicles

The influence of environmental temperatures on the fatigue strength of compressed-hydrogen tanks for vehicles was investigated. The fatigue strength of Type-3 tanks was found to decrease in a low-temperature environment and increase in a high-temperature environment. The Type-3 tank has been subjected to autofrettage to improve fatigue strength. The investigation clarified that the effect of autofrettage changes according to the environmental temperature due to the difference between the coefficients of thermal expansion of carbon fiber reinforced plastic and aluminum alloy. This causes fatigue strength to change with changes in temperature. The Type-4 tank has a very long fatigue life and did not break after 45,000 cycles in a room-temperature or low-temperature environment. In a high-temperature environment, however, the tank broke in fewer than 45,000 cycles. The fatigue of carbon fiber reinforced plastic was promoted in the high-temperature environment, resulting in breakage of the tank. These results indicate that the fatigue strength of the tanks is influenced by the environmental temperature.