New oxide phosphors for FEDs: Ruddlesden—Popper phases synthesized with IIIB‐group elements

Abstract— A red‐emitting phosphor, SrTiO³:Pr³⁺, for low‐voltage‐type FEDs and VFDs was developed by Futaba Corporation in 1996. The addition of Al or Ga is essential in the preparation of this phosphor because it improves the luminescence efficiency dramatically. For this impurity effect, Futaba Corporation proposed a charge‐compensation mechanism, which was supported by a recent observation of emission lines due to Al³⁺‐Pr³⁺ pairs. In addition, it was found that Al also works as a scavenger of planar defects, presumably SrO thin layers interleaved in the SrTiO³ lattice, by forming strontium aluminates. The latter mechanism suggests the possibility that a similar impurity effect can be found in materials with crystal structures, including alkaline‐earth oxide layers (Ruddlesden‐Popper phases).     

Effect of cold rolling on the superconducting and electronic properties of two amorphous alloys; Nb50Zr35Si15 and Nb70Zr15Si15

The effect of cold rolling on the superconducting properties was examined for amorphous Nb₅₀Zr₃₅Si₁₅ and Nb₇₀Zr₁₅Si₁₅ superconductors. Cold rolling to 10 to 20% reduction in thickness results in a rise of superconducting transition temperature (T _c) and a decrease in transition width (T _c), upper critical field gradient near , critical current density [J _c(H)] and normal electrical resistivity (_n). Changes of about 7% forT _c 33% for T _c, 12% for and 70% forJ _c(H) are found. The rise ofT _c upon cold rolling was considered to originate from the increase in the electron-phonon coupling constant () due to an increase in the electronic density of states at the Fermi level [N(E _f)] and a decrease in the phonon frequency (), while the decreases in T_c,J _c(H) and _n were attributed to the decrease in fluxoid pinning force due to an increase in homogeneity in the amorphous structure. From the results described above, the following two conclusions were derived: (a) cold rolling causes changes in electronic and phonon-states in the quenched amorphous phase, and (b) deformation upon cold rolling occurs not only in the coarse deformation bands observable by optical microscopy, but also on a much finer scale comparable to the coherence length (7.7 nm).     

Development of an Autonomous Robot for Gas Storage Spheres Inspection

Inspection for corrosion of gas storage spheres at the welding seam lines must be done periodically. Until now this inspection is being done manually and has a high cost associated to it and a high risk of inspection personel injuries. The Brazilian Petroleum Company, Petrobras, is seeking cost reduction and personel safety by the use of autonomous robot technology. This paper presents the development of a robot capable of autonomously follow a welding line and transporting corrosion measurement sensors. The robot uses a pair of sensors each composed of a laser source and a video camera that allows the estimation of the center of the welding line. The mechanical robot uses four magnetic wheels to adhere to the sphere’s surface and was constructed in a way that always three wheels are in contact with the sphere’s metallic surface which guarantees enough magnetic atraction to hold the robot in the sphere’s surface all the time. Additionally, an independently actuated table for attaching the corrosion inspection sensors was included for small position corrections. Tests were conducted at the laboratory and in a real sphere showing the validity of the proposed approach and implementation.     

Surface degradation of polyamide nanocomposites caused by partial discharges using IEC (b) electrodes

Partial discharge (PD) degradation of polyamide both without nanoscale fillers (nanofillers) and with 2,4 and 5 wt% additions of nanofillers was investigated. Such materials were subjected to PDs using the IEC (b) electrodes for evaluation. Comparisons were made as to the surface roughness observed by scanning electron microscopy and atomic force microscopy. It was found that the change in the surface roughness is far smaller in specimens with nanofillers than those without nanofillers, and that the 2 wt% addition is sufficient for improvement of the surface roughness. Furthermore, it was elucidated that the difference of surface roughness of the degraded area due to PDs among the specimens originates from the difference in their crystalline structures. These results indicate that polyamide nanocomposite is more resistance to PDs than polyamide without nanofillers.     

Clinically applicable bulk isolation of blood CD34+ cells for autografting in children

The quality of population-based cancer registries has been measured by the indices of the proportion of total incident cases (DCO%) registered by death certificate only (DCO), and the ratio of incidence to mortality (I/D ratio). Recently it has been recommended that DCO% should be used as an index for the reliability of diagnosing cancers and that the proportion of cases first notified via death certificate (DCN, DCN%) be used as an index for the completeness of registration. Parkin introduced a method to estimate the registration rate, the estimated proportion of the "true incidence" that are registered in population-based registries. We recommend a modified method for estimating the registration rate for cancer registries where DCN% is relatively high, as it is in Japan, as Parkin's method may overestimate the registration rate. The method is as follows: the registration rate = (1-DCN% x 1/D ratio)/(1-DCN%). The registration rates at the Osaka Cancer Registry between 1966 and 1992 were estimated using our method. During this period, the yearly registration rate was 74.6-78.4% for males and 69.1-73.3% for females. When the cancer cases were looked at according to site, the yearly registration rate was 74.2-81.6% for stomach cancer, 81.2-89.3% for lung cancer, and 71.3-76.9% for uterine cancer. These results show that the registration rate is high for cancers that have an unfavorable prognosis and low for cancers that have a favorable prognosis. We recommend that all cancer registries in Japan calculate the completeness of registration by utilizing DCN defined as the sum of DCO plus cases not reported as cancer but with supportive clinical information of such obtained through survey of the registry for DCN.     

Blind source extraction of long-term physiological signals from facial thermal images

The amount of mental work using information equipment has been increasing because of a rapid growth of an information society. Accumulation of short-term mental work can cause various stresses and a disturbance of circadian rhythm and lead to fatigue, anxiety, and distraction. Estimation and understanding the physiopsychological states is desired for decreasing or controlling stresses to maintain health. There have been several investigations on the assessment of short-term physiopsychological states using infrared thermography. However, the method has been used rarely for assessing long-term physiopsychological states. In the present study, extraction of independent components related to long-term physiological signals is attempted by applying independent component analysis to facial thermal images obtained over 6 months (July–December). Furthermore, multiple regression analysis is attempted to create psychological model by facial thermal images. As the result, extracted independent components are shown to represent the strong features in nasal, mouth, cheek, eyebrow, and forehead regions. Attempting multiple regression analysis, features in nasal and mouth regions contributed to depression or dejection mood, features in cheek, eyebrow and forehead regions contributed to fatigue and features in tip of nasal, eyebrow and mouth regions contributed to state anxiety.     

MOCVD preparation of SBTN thin films from two organometallic sources bottles

Abstract

SrBi₂(Ta_0.7Nb_0.3)₂O₉ (SBTN) films were first prepared on (111)Pt/Ti/SiO₂/Si substrates by MOCVD from only two organometallic source bottles. Bi(CH₃)₃ and the mixture of Sr[Ta(O°C₂H₅)₆]₂ and Sr[Nb(O°C₂H₅)₆]₂ were used as source materials. High compositional reproducibility was obtained; the Nb/(Ta+Nb) ratio was the same as the mixing ratio of the source. Sr/(Ta+Nb) and Bi/(Ta+Nb) ratios can be controlled by the reactor pressure and the input gas flow rate ratio of the source gases. Almost single phase of SBTN was obtained for the film deposited at 500°C and the following heat-treated at 800°C in O₂ atmosphere. Pr and Ec values of 330 nm-thick SBTN film were 8.5 μC/cm² and 91 kV/cm, respectively and were larger than those of SrBi₂Ta₂O₉ film. There was no degradation after 5x10¹⁰ cycles polarization switching.