In situ observation of nucleation and growth of iron whiskers from supersaturated wüstite

Iron whiskers have been found to form from iron-supersaturated wüstite by cooling without any chemical reaction. In situ observation of the nucleation and growth was successfully achieved by scanning electron microscopy and recorded by 16-mm films. Much knowledge regarding the predominant nucleation site, shape and thickness, elongation rate, effect of dopants, etc., has been obtained.     

Hybrid Planar Wiggler with a Period of 2 cm for Higher Harmonic FEL Lasing

A hybrid planar wiggler with a period of 20 mm has been studied as the simplest one which gives the strong field including some higher harmonic components by selecting proper sizes of the ferromagnetic and the permanent magnet. Small gap length of the wiggler and small width of permendur satisfy these conditions to a certain degree. Gain analysis of FEL suggests that for high wiggler field of K>1 ～ 1.6, higher harmonic gains are improved primarily due to its strong field, and for low wiggler field of K< 1 ～ 1.6, they are mainly due to the modification of the wiggler field distribution.     

Spontaneous resolution of pulmonary cryptococcosis--report of 2 cases

YUA001 is a novel aldose reductase inhibitor produced from alkalophilic Corynebacterium sp. YUA25 isolated from soil. YUA001 was purified from the supernatant of culture broth by successive silica gel column chromatography, Sephadex LH20-100 gel column chromatography, and HPLC. From instrumental analysis, molecular formula of YUA001 is C13H19NO2 and its molecular weight is 221. It exhibits potent aldose reductase inhibition activity and has no antimicrobial activity against some gram-positive or gram-negative bacteria, fungi and yeast.     

Image similarity based on Discrete Wavelet Transform for robots with low-computational resources

This paper describes a similarity measure for images which can be used in image-based topological localization and topological SLAM problems by autonomous robots with low computational resources. Instead of storing the images in the robot’s memory, we propose a compact signature to be extracted from the images. The signature is based on the calculation of the 2D Haar Wavelet Transform of the gray-level image and its size is only 170 bytes. We called this signature the DWT-signature. We exploit the frequency and space localization property of the wavelet transform to match the images grabbed by the perspective camera mounted on board the robot and the reference panoramic images built using an automatic image stitching procedure. The proposed signature allows, at the same time, memory saving and fast and efficient similarity calculation. For the topological SLAM problem we also present a simple implementation of a loop-closure detection based on the proposed signature.We report experiments showing the effectiveness of the proposed image similarity measure using two kinds of small robots: an AIBO ERS-7 robot of the RoboCup Araibo Team of the University of Tokyo and a Kondo KHR-1HV humanoid robot of the IAS-Lab of the University of Padua.     

3D IMAGING OF INVERTED DOMAIN STRUCTURES BY CONFOCAL SHG INTERFERENCE MICROSCOPE

ABSTRACT

A novel nonlinear optical interference microscope which enables us to take 3D images of ferroelectric domain structures is developed. This microscope is of a transmission type equipped with the confocal optical system, and exploits, as a probe, second harmonic waves generated in a sample by an incident laser beam. We apply the microscope to the observation of periodically poled domain structure in a LiTaO₃ quasi-phase matching device.     

Effect of aluminum and titanium additions to Fe-21%Cr-32%Ni on the oxidation behavior in an impure helium atmosphere at high temperatures

The effects of aluminum and titanium additions on the oxidation and carburization behavior of Fe-21%Cr-32%Ni in an HTGR-simulated impure helium environment at high temperatures were studied. Intragranular and intergranular oxidation were the principal forms of degradation, with the effect of aluminum being major and that of titanium relatively minor. As the aluminum content in the alloy increased, the mode of degradation changed from both uniform intragranular and intergranular oxidation, to one involving only uniform intragranular oxidation. This transition in the degradation mode was explained by the volume changes in the alloy resulting from a combination of both a volume increase due to internal-oxide precipitation and shrinkage due to the condensation of vacancies formed as a result of selective removal of alloying elements to the external scale. Intergranular oxidation was observed only when the resultant volume change was due to shrinkage. When the resultant volume change was positive, only uniform intragranular oxidation occurred and at the same time, extensive carburization was observed probably due to the deterioration of the surface scale caused by the deformation of the alloy substrate. A small amount of titanium, ca. 0.4%, appeared to modify the phenomena caused by aluminum additions, e.g., causing increased intergranular penetration for the 0.4% Al alloy and internal-to-external transition for the 2.1% Al alloy. External scale formation without any internal oxidation was observed for alloys containing more than 1.9% Al at 973 and 1023 K and for an alloy containing 2.1% Al and 0.4% Ti at 1073 and 1123 K. In these cases, carburization was almost completely eliminated.     

Knowledge engineering and CAD

The technology of Computer Aided Design (CAD) has rapidly been changing the processes of machine design, especially in detail and production design. Conventional CAD systems are necessary in production design where precise geometrical data are indispensable, but we can point out some problems of those systems from a point of view of the total machine design process. Though the main aim of introducing CAD systems is to increase designers' creativities, it is doubtful whether designers are really supported by such CAD systems. We think that knowledge engineering is useful to improve such situations. In this paper, we discuss these problems and we study the feasibilities of future CAD systems that can really help designers very intelligently and efficiently. We also show some results of our experimental systems applying knowledge engineering.     

A natural soil and mechanism of removal: Part II

Based on the findings of interaction between dodecyl benzene sulfonate (DBS) and high molecular weight nitrogen compounds in natural soil in the first report of this series, artificially soiled clothes containing protein were prepared and a washing test was carried out with a use of DBS or nonyl phenol-polyoxyethylene adduct (NPEO). Cattle serum globulin, cod sperm protamine and feather keratin of wild duck were used as protein. The built DBS detergent showed better detergency on the artificially soiled clothes than the built NPEO detergent at a same surfactant concentration of 0.05%, although no difference was observed in the redeposition test between these detergents. A significant dissolving action of DBS was observed. Results indicate that when discussing the mechanism of dissolution of natural soil or in the course of modifying the artificially soiled clothes, a chemical reaction between DBS and protein had to be considered in addition to the well known physico-chemical surface activity of the surfactant for removal of soil.