Geometrical structures and fundamental characteristics of microwavestepped-impedance resonators

λ_g/4-,λ_g/2-, and λ_g-type transmission-line stepped-impedance resonators (SIRs) have been proposed and various practical applications have been reported on the basis of the analysis related to each resonator. This paper standardizes these three types of SIRs and systematically summarizes their fundamental characteristics, such as resonance conditions, resonator length, spurious (higher order) responses, and equivalent circuits. Practical applications which employ features of three types of SIRs are investigated with demonstrations of specific structures. Original design formulas with respect to λ_g-type dual-mode resonators are analytically derived. Advanced SIR's using composite material and multisteps are also introduced and their availability is discussed     

Development of glutamate-induced intracellular Ca2+ rise in the embryonic chick retina

Plasmids derived from bacteriophage lambda are known as lambda plasmids. These plasmids contain the ori lambda region and lambda replication genes O and P. Typical lambda plasmids also contain the cro gene, the product of which is a repressor of the pR promoter when present at relatively high concentrations. These genes stably maintain the plasmid in Escherichia coli at copy numbers of 20 to 50 per cell. According to a generally accepted model, stable maintenance of lambda plasmids is possible due to the Cro repressor autoregulatory loop (the cro gene is under control of pR). Here we demonstrate that lambda plasmids devoid of the Cro autoregulatory loop can also be stably maintained in E. coli strains. We present data for two such plasmids: pTC lambda 1 in which the pR-cro region has been replaced by the ptetA promoter and the tetR gene (coding for the TetR repressor), and a standard lambda plasmid with inactivated cro gene (lambda cro-null plasmid). Thus, the presence of the Cro repressor autoregulatory loop does not appear to be essential to the maintenance of lambda plasmids in vivo.     

Transmission line aspects of the design of broad-band electrooptic traveling-wave modulators

This paper proposes a two-layer traveling-wave type electrooptic modulator structure to maximize modulation bandwidth from transmission line aspects. This structure can be designed to satisfy the velocity matching and impedance matching condition simultaneously. A design method for this structure is discussed.     

In-situ cathodoluminescence spectroscopy of silicon oxide thin film under uniaxial tensile loading

In this paper, in-situ cathodoluminescence (CL) stress analysis of a silicon oxide (SiO(x)) thin film prepared by wet thermal oxidation is described. The specially-developed uniaxial tensile loading jig was used to apply tensile displacement to the SiO(x) film specimen. CL spectra of the specimen during tensile loading were obtained, and the peak position of around 1.85 eV emission band was monitored for tensile stress analysis. The peak position gradually shifted towards higher/lower energy side when tensile displacement increased/decreased. The tensile stress-to-emission energy ratio of 6.21-8.97 x 10(2) GPa/eV was estimated on the basis of linear elastic theory, which demonstrated that CL is able to provide information on stress induced in the film. Scanning electron microscopy (SEM) revealed that the fracture of SiO(x) and SCS laminated structure occurred at the vicinity of SiO(x) film surface.     

Discussion on optimisation below dose limit for public using background-cancer-risk-based approach

To improve a radiological protection system, the lower bound of optimisation was discussed using a newly proposed background-cancer-risk-based approach. This approach provides a new finding that the standard deviation of the background cancer risk in Japan is 7.4 × 10(-5) y(-1). If this risk level corresponding to 1σ can be regarded as a non-concern level, it would be possible that the lower bound of optimisation of radiological protection could be set at 1 mSv y(-1), since the assumed risk of 1 mSv y(-1) is equivalent to ~5 × 10(-5) y(-1) obtained using the overall fatal risk coefficient of 5 % Sv(-1), which is lower than the non-concern level.     

A size controlled synthesis of CuS nano-particles in the protein cage,apoferritin

CuS compound semiconductor nanoparticles (NPs) were prepared in the 7 nm inner cavity of apoferritin, a cage-shaped protein composed of 24 subunits forming a cage-like structure, 12 nm in diameter. The average core diameter of the NPs synthesized in the apoferritin cavity was 5 nm with narrow size distribution. The synthesized NP cores were analyzed and confirmed by EDS, XRD and HR-TEM as hexagonal poly crystalline. The CuS NP core synthesis took 3 h and the synthesis manner was all-or-nothing core formation. This water-soluble and homogeneous CuS semiconductor NP has the potential to be used in the construction of nanostructures.     

Sterically controlled docking of gold nanoparticles on ferritin surface by DNA hybridization

Novel assemblies of DNA-functionalized gold nanoparticles (DNA-GNPs) have received considerable interest due to their fascinating properties which are desired for various detection applications. In this study, we present innovative GNP assemblies which have a cage-shaped protein ferritin in the center, and discrete GNPs sterically surrounding the central ferritin. These assemblies were constructed by hybridizing DNA-GNP to chemically DNA-modified ferritin, which has a hollow cavity or an iron NP core. Subsequent gel electrophoresis purification and transmission electron microscopy observation showed that ferritin/DNA/GNP assemblies were successfully constructed and can be isolated as independent functional units, which can be used to investigate not only the interaction between the GNPs of complicated GNP clusters but also the interaction between the GNPs and the internalized NP.     

Grain boundary engineering of austenitic steel PNC316 for use in nuclear reactors

Austenitic stainless steel PNC316 was subjected to grain boundary engineering (GBE). It was found that the grain boundary engineered PNC316 (PNC316-GBEM) had a coincidence site lattice (CSL) fraction of 86% and that the network of random grain boundaries was perfectly divided by the CSL boundaries. The thermal stability and the void swelling behavior of PNC316-GBEM were investigated by means of SEM and TEM analyses. After thermal aging at 973 K for 100 h, structural changes were observed neither in the grain boundary networks of PNC316-GBEM nor in another sample of PNC316-GBEM subjected to 20% additional cold rolling, PNC316-GBEM20%CW. PNC316-GBEM showed a higher void swelling rate than as-received PNC316 (PNC316-AS). However, with additional 20% cold rolling after GBE, the void swelling rate decreased to as low as that of PNC316-AS.     

Modeling of eddy characteristic time in LES for calculating turbulent diffusion flame

We have constructed an eddy characteristic time derived from large-scale motion to calculate the combustion reaction rate using a new eddy dissipation concept (EDC) model, and estimated combustion characteristics in the combustor. The calculated temperature and CH₄ mole fraction distribution are in fairly good agreement with the experimental data. However, the calculated CO mole fraction distribution does not agree well with the measured result of CO mole fraction because of using a simple CO reaction mechanism. This study shows that the combustion simulation using LES with EDC model is effective for calculating the characteristics of turbulent diffusion flame.