Sensitivity and Evaluation of Explosive Substances

Explosion sensitivity involves many complex factors. A theory for evaluating and a method for testing have to be established. We have proposed an explosion sensitivity theory for explosive substances and have also tested the evaluating method. The results of our research reveal a satisfactory mutual relation between both theoretical and experimental values.     

HNF1A Mutations and Beta Cell Dysfunction in Diabetes

Understanding the genetic factors of diabetes is essential for addressing the global increase in type 2 diabetes. HNF1A mutations cause a monogenic form of diabetes called maturity-onset diabetes of the young (MODY), and HNF1A single-nucleotide polymorphisms are associated with the development of type 2 diabetes. Numerous studies have been conducted, mainly using genetically modified mice, to explore the molecular basis for the development of diabetes caused by HNF1A mutations, and to reveal the roles of HNF1A in multiple organs, including insulin secretion from pancreatic beta cells, lipid metabolism and protein synthesis in the liver, and urinary glucose reabsorption in the kidneys. Recent studies using human stem cells that mimic MODY have provided new insights into beta cell dysfunction. In this article, we discuss the involvement of HNF1A in beta cell dysfunction by reviewing previous studies using genetically modified mice and recent findings in human stem cell-derived beta cells.     

High-performance carbon counter electrode for dye-sensitized solar cells

Here, we reported that a new carbon electrode prepared with an activated carbon was superior to a Pt sputtered electrode as the counter electrode of dye-sensitized solar cells. The photovoltaic performance was largely influenced by the roughness factor of carbon electrode. The open-circuit voltage increased by about 60 mV using the carbon counter electrode compared to the Pt counter electrode because of positive shift of the formal potential for I₃⁻/I⁻ couple.     

Alignment control of liquid crystals in a 1.0‐μm‐pitch spatial light modulator by lattice‐shaped dielectric wall structure

We achieved uniform liquid crystal (LC) alignment in lattice‐shaped dielectric walls 1 μm in pitch; this is a prerequisite when driving the individual pixels of spatial light modulators, facilitating the development of practical electronic holographic displays with a wide field of view. In lattice‐shaped dielectric walls, LC alignment becomes unstable, particularly on the bottom and the walls; the LC directors tend to align parallel to the walls. To overcome this problem, we created lattice‐shaped walls featuring partition plates that allow uniform LC alignment. When the plates confine LCs to small regions exhibiting spatial anisotropy, the LC elastic effect and wall anchoring forces align the LC directors parallel to the long anisotropic axis. We found that pixels 0.5 μm × 1.0 μm in pitch formed if the partition plates were sufficiently thick to allow shielding of electric field leakage.     

Synthesis of zirconia sphere particles based on gelation of sodium alginate

Zirconia sphere particles were synthesized through the gelation process of Na-alginate, and cermet (ZrO₂-Mo) pellets were fabricated under several conditions. In this process, a zirconia slurry was prepared by mixing oxide powders (ZrO₂, Y₂O₃, Er₂O₃, CeO₂), distilled water and Na-alginate, and subsequently dropped into CaCl₂ solution. As a result, zirconia sphere particles coated with a gelled film were synthesized. The slurry density (zirconia content in slurry) of 30-64 wt.% and Na-alginate concentration of a few% were good for gelation for up to 10 wt.% CaCl₂ solution. Sphere particles with smaller diameter were obtained by dropping slurry with a mechanical vibration. The prolongation of the ball milling time for mixture of oxide powders was effective to increase the sintered density of zirconia sphere particles, especially for higher CeO₂ concentration. The dense cermet pellets were fabricated for max. 50% volume ratio of zirconia phase for Mo matrix using zirconia particles covered with Mo powder by a rotating granulation method.     

野外试验场黄土的理化分析

本实验为低,中水平放射性废物浅地层处置安全评价提供现场土壤的物理化学参数。采样深度在０．５－９．１ｍ范围内,每个样品进行１０项测定;矿物组成,粒度分布、密度、总孔隙度、有效孔隙度、给水度、持水度、渗透系数、阳离子交换容量、含水量。     

Propagation Path Visibility Estimation for Radio Local Distribution Systems in Built-Up Areas

For the design of radio local distribution systems in densely built-up areas, estimating how many subscribers are in sight from a nodal station is important. This paper proposes a method for estimating probability of success of line-of-sight paths termed visibility. Method validity is confirmed bypractical field examinations.     

Frequency stabilization of GaAlAs laser using a Doppler-free spectrum of the Cs-D2line

Experimental results are shown on the frequency stabilization of a GaAlAs laser using a Doppler-free spectrum in the saturated absorption of the Cs-D2line at 852.1 nm. The frequency stability (Allan variance) between3.0 times 10^{-12}and1.0 times 10^{11}was obtained at the averaging time between 0.1 and 1000 s.