Shape optimization for a link mechanism

This paper presents a numerical solution for shape optimization problems for link mechanisms, such as a piston-crank mechanism. The dynamic behavior of a link mechanism is described by a differential-algebraic equation (DAE) system consisting of motion equations for each single body and constraints of linkages and rigid motions. In a shape optimization problem, the objective function to maximize is constructed from the external work done by a given external force, which agrees with the kinetic energy of the link mechanism, for an assigned time interval, and the total volume of all the links forms the constraint function. The Fréchet derivatives of these cost functions with respect to the domain variation, which we call the shape derivatives of these cost functions, are evaluated theoretically. A scheme to solve the shape optimization problem is presented using the H ¹ gradient method (the traction method) proposed by the authors as a reshaping algorithm, since it retains the smoothness of the boundary. A numerical example shows that reasonable shapes for each link such that mobility of the link mechanism is improved are obtained by this approach.     

Chemical modification of group IV graphene analogs

Mono-elemental two-dimensional (2D) crystals (graphene, silicene, germanene, stanene, and so on), termed 2D-Xenes, have been brought to the forefront of scientific research. The stability and electronic properties of 2D-Xenes are main challenges in developing practical devices. Therefore, in this review, we focus on 2D free-standing group-IV graphene analogs (graphene quantum dots, silicane, and germanane) and the functionalization of these sheets with organic moieties, which could be handled under ambient conditions. We highlight the present results and future opportunities, functions and applications, and novel device concepts.     

New pixel driving circuit using self‐discharging compensation method for high‐resolution OLED micro displays on a silicon backplane

A new 4T2C pixel circuit formed on a silicon substrate is proposed to realize a high‐resolution 7.8‐μm pixel pitch AMOLED microdisplay. In order to achieve high luminance uniformity, the pixel circuit compensates its Vth variation of the MOSFET for the driving transistor internally by using self‐discharging method. Also presented are 0.5‐in Quad‐VGA and 1.25‐in wide Quad‐XGA microdisplays with the proposed pixel circuit.     

A high-resolution transmission electron microscope study of a zinc oxide varistor

Investigations were made of varistor microstructure, the morphology of Bi₂O₃ at multiple ZnO grain junctions, Bi₂O₃/ZnO grain boundaries and ZnO/ZnO grain boundaries (especially whether Bi₂O₃ is present or not at the ZnO/ZnO grain boundary) by means of high-resolution transmission electron microscopy and X-ray microanalysis in the scanning transmission electron microscope. Bi₂O₃ at multiple ZnO grain junctions consists of small particles of 0.1m in diameter, and they are vitrified to some extent. It is suggested that bismuth ions dissolve into ZnO grains over a 30 nm range from a Bi₂O₃/ZnO grain boundary; however, there is no bismuth at ZnO/ZnO grain boundaries.     

Evaluation of Desulphurization Flux in CaO‐Al2O3‐BaO‐CeO2‐MgO System

The flux of the CaO‐Al₂0₃‐BaO‐CeO₂‐MgO system as a desulphurization flux containing no fluorine for the secondary metallurgy process was evaluated in this study. The flux composition was designed using the eutectic compositions of the binary systems. The melting and desulphurization abilities of the fluxes were evaluated by measuring their liquidus temperatures and the distribution ratios of sulphur between the fluxes and the carbon‐saturated iron or stainless steel. The lowest liquidus temperature of 1325°C was obtained by adding 5.7 mass% MgO to the 80mass%A‐20mass%B flux. (A: 12CaO‐7Al₂O₃, B: BaCeO₃+12mass%Al₂O₃). The distribution ratios of sulphur and sulphide capacities of the fluxes in this study were higher than those of the commercial product of calcium aluminate flux. This means that the CaO‐Al₂O₃‐BaO‐CeO₂‐MgO fluxes developed in this study have higher desulphurization and melting abilities compared with the commercial product of calcium aluminate flux.     

Long Preservation of AAV-Transduced Fluorescence by a Modified Organic Solvent-Based Clearing Method

The development of tissue clearing technologies allows 3D imaging of whole tissues and organs, especially in studies of the central nervous system innervated throughout the body. Although the three-dimensional imaging of solvent-cleared organs (3DISCO) method provides a powerful clearing capacity and high transparency, the rapid quenching of endogenous fluorescence and peroxide removal process decreases its practicability. This study provides a modified method named tDISCO to solve these limitations. The tDISCO protocol can preserve AAV-transduced endogenous EGFP fluorescence for months and achieve high transparency in a fast and simple clearing process. In addition to the brain, tDISCO was applied to other organs and even hard bone tissue. tDISCO also enabled us to visualize the long projection neurons and axons with high resolution. This method provides a fast and simple clearing protocol for 3D visualization of the AAV- transduced long projection neurons throughout the brain and spinal cord.     

Changes in lipids and their contribution to the taste of migaki-nishin (dried herring fillet) during drying

This study was conducted to investigate the changes in lipids and their effect on the taste of migaki-nishin during drying. Lipid was extracted from herring fillets following different drying stages to measure the degree of lipid oxidation and changes in lipid composition, and fatty acid profile. Peroxide value, carbonyl value and acid value of the lipids were significantly increased (P < 0.05) during the drying period. Marked increase in free fatty acids, with decreases in triglyceride and phospholipid content were observed in proportion to drying time and this result suggested that hydrolysis was induced by lipases and phospholipases. The decreases in polyunsaturated fatty acids (PUFAs), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), were observed in the total lipids and phospholipid fraction. In addition, significant increase in PUFAs especially DHA was found in the free fatty acid fraction. Sensory evaluation showed that an addition of DHA to mentsuyu significantly (P < 0.05) enhances the intensities of thickness, mouthfulness and continuity. These results suggest that during drying period lipid oxidation was not only occurred but also lipolysis predominantly released DHA, which might have a contribution to kokumi enhancement of migaki-nishin.     

Fabrication of Bulk β-FeSi2 Crystal With ThreeDimensional Alignment by an Oscillating Magnetic Field

It has been reported that an anisotropic magnetic field could produce the three-dimensional alignment of fine single-crystal particles with the orthorhombic crystal structure.However,the three-dimensional alignment was achieved only in suspensions.Fabrication of bulk"single"materials that have the three-dimensional alignment of grains has been desired.This study proposes a procedure for the fabrication,which consists of slip casting under an oscillating magnetic field and sintering.Optimization of casting and sintering conditions achieved the three-dimensionally aligned bulkβ-FeSi₂.