Scattering angle dependence of signal/background ratio of inner-shell electron excitation loss in eels

Scattering angle dependence of the signal/background ratio of Si K-shell and A1 K-shell electron excitation losses has been measured for single crystals and evaporated films. The ratio changed periodically with the scattering angle, and maxima were found to be located between Bragg reflections including the center beam. Thus the ratio is improved between the Bragg reflections and just outside the incident beam, which is very important as a practical technique for elemental analysis in the higher energy loss region in EELS.     

Oxygen Configuration in the Superconductor (Hg0.7Mo0.3)Sr2(Ca1?xRx)Cu2Oz (R = Nd and Pr)

Two series of Hg-based oxides (Hg_0.7Mo_0.3)Sr₂(Ca_1–x R _x )Cu₂O _z (R = Nd and Pr, 0.2 x 0.7) have been synthesized. Electrical-resistivity measurements show that these compounds are superconductors with maximum onset T _c of 107 and 102 K for Nd- and Pr-containing samples, respectively. The neutron powder diffraction experiments on both as-prepared and O₂-annealed samples of R = Nd revealed that the O(3) site at the HgO sheets are fully occupied and shifted towards the Hg/Mo site to form Mo–O bonds.     

Self-organized one-axis-oriented PZT films with nano-domain structure

{100} One-axis-oriented PZT films with a thickness of 2 μm were obtained on (111)Pt/TiO₂/SiO₂/(100)Si substrates by metal organic chemical vapor deposition (MOCVD). These were obtained irrespective of the film thickness up to 2 mm and with a Zr/(Zr + Ti) ratio from 0.20 to 0.75. This was found to be due to the higher growth rate of these orientation grains than {110} and {111)} orientation grains. These films had columnar grains 50–100 nm in width. Moreover, they were found to include 908 nano-domains 10–20 nm in width. Dielectric constant, ε_r and the field induced-strain were maximum around a Zr/(Zr + Ti) ratio of 0.5, which was in good agreement with previous reports on sintered bodies with 100 times larger domains. This means that the domain size had any effect on ε_r or field-induced strain.     

Fabrication of size-controlled polyimide nanoparticles

Polyimide particles were fabricated through the two-steps imidization of poly(amic acid) particles prepared by using reprecipitation method. PAA and PI nanoparticles were all spherical, and the changes of particle size, its distribution, and morphology were not observed before and after the imidization. The preparation of PI nanoparticles size-controlled between ca. 20-500 nm was also achieved by changing the experimental conditions, temperature of the poor solvent, the composition of two kind of poor solvent, and PAA-NMP solution concentration.     

Structural classification and similarity measurement of malware

This paper proposes a new lightweight method that utilizes the growing hierarchical self‐organizing map (GHSOM) for malware detection and structural classification. It also shows a new method for measuring the structural similarity between classes. A dynamic link library (DLL) file is an executable file used in the Windows operating system that allows applications to share codes and other resources to perform particular tasks. In this paper, we classify different malware by the data mining of the DLL files used by the malware. Since the malware families are evolving quickly, they present many new problems, such as how to link them to other existing malware families. The experiment shows that our GHSOM‐based structural classification can solve these issues and generate a malware classification tree according to the similarity of malware families. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Thermochromism in an organic crystal based on the coexistence of sigma- and pi-dimers

Transition-metal complexes and organic radical molecules can be used to make electric conductors and ferromagnets, the optical properties of which can be controlled by changing temperature and are used as molecular switches and sensors. Whereas a number of organic radicals in solution show temperature-dependent optical properties, such behaviour in crystalline forms is more rare. Here, we show a fully reversible continuous thermochromism with a unique mechanism in purely organic crystals of diazaphenalenyl radical. This behaviour is based on changes in the diazaphenalenyl dimers coexisting in the crystal. From the X-ray crystal structure analyses and temperature-dependent visible spectra, we conclude the presence of a thermal equilibrium between sigma-bonded and pi-bonded dimers, which are separated by 2.62(6) kcal mol(-1). This conclusion is supported by room-temperature electron spin resonance spectra of the solid, which showed signals that are attributable to a thermally accessible triplet state of the pi-dimer structure. This proves the coexistence of two dimers of different bonding natures in the crystal, causing it to demonstrate thermometer-like behaviour.     

Automatic detection and visualization system for coronary artery calcification using optical frequency domain imaging

Artificial Life and Robotics - Percutaneous coronary intervention (PCI) is mainly used in the treatment of stenosis of the coronary arteries of the heart characteristic of coronary artery disease,...