Path Integral Treatment of Proton Transport Processes in BaZrO3

Nuclear quantum effects on proton transfer and reorientation in BaZrO3 is investigated theoretically using the ab initio path-integral molecular-dynamics simulation technique. The result demonstrates that adding quantum fluctuations has a large effect on, in particular, the transfer barrier. The corresponding rates and diffusion coefficient are evaluated using the path-centroid transition state theory. In contrast with what is found assuming classical mechanics for the nuclear motion, the reorientation step becomes rate limiting below 600 K

Structural Basis of the Association of HIV-1 Matrix Protein with DNA

HIV-1 matrix (MA) is a multifunctional protein that is synthesized as a polyprotein that is cleaved by protease during viral maturation. MA contains a cluster of basic residues whose role is controversial. Proposed functions include membrane anchoring, facilitating viral assembly, and directing nuclear import of the viral DNA. Since MA has been reported to be a component of the preintegration complex (PIC), we have used NMR to probe its interaction with other PIC components. We show that MA interacts with DNA and this is likely sufficient to account for its association with the PIC

Electronic and Structural Properties of a 4d-Perovskite: Cubic Phase of SrZrO3_3

First-principles density functional calculations are performed within the local density approximation to study the electronic properties of SrZrO$_3$, an insulating 4d-perovskite, in its high-temperature cubic phase, above 1400 K, as well as the generic 3d-perovskite SrTiO$_3$, which is also a d^0-insulator and cubic above 105 K, for comparison reasons. The energy bands, density of states and charge density distributions are obtained and a detailed comparison between their band structures is presented. The results are discussed also in terms of the existing data in the literature for both oxides.Comment: 5 pages, 2 figure

Introduction of a Base-Model for Eddy Current Testing of Printed Circuits Boards

In this paper we propose a model to reproduce printed circuit board (PCB) pattern eddy current testing signals based on 3D finiteelement method (FEM) package and scanning simulation. In this method we consider some common PCB elements as test pieces while a simple Meander-type coil is utilized as excitation coil above the elements. Numerical solution to the above problem with the help of a 3D FEM provides the magnetic flux density in the region above the PCB test elements. Shifting the test element\u27s position step by step and repeating the numerical calculation for each of the test elements new positions, the scanning process of a PCB test piece is simulated. Analysing and smoothing the magnetic field data from all of the aforementioned steps provide the final PCB pattern signal. Image processing technique was applied to obtain the PCB part image

Conductive micro-bead array detection by high-frequency eddy-current testing technique with SV-GMR sensor

岩原, 正

Application of ECT Technique for Inspection of Bare PCB

The detection of imperfections (such as disconnections, chipping cracks, nonuniformity in thickness and short-circuit, etc.) on the traces of bare printed circuit board (PCB) using a new high-sensitive eddy-current testing (ECT) probe has been reported in this paper. The ECT technique is composed of planar meander type exciting coil and a new multiple solenoid sensing coil. The image processing method is used to analyze the results. This paper has discussed the structure of the new probe, the characteristics of the measurement technique to inspect high-density PCB with narrow conductor-width. And the possibility of detecting micro-metal ball has been explored.A new application of eddy current testing techniques for investigating trace defects on printed circuit boards is proposed, A test probe consisting of a meander type exciting coil is used to induce eddy currents. The following three experiments are conducted: measuring the induced signal when a circuit trace is cut; measuring the induced signal for a number of traces placed in parallel and with a cut in the centre trace; measuring the induced signal for two back to back right angle traces. The experimental results reveal that it is possible to clearly detect defects and that the signal response obtained is strongly associated with a particular defect pattern. The signals obtained from a high density patterned board have a complicated signal signature and are therefore difficult to interpret. This complexity can be avoided by comparing the signal signature of a known good board with a defective board. The difference signal gives a clear indication of a trace defect

Application of Eddy-current testing technique for high-density double-layer printed circuit board inspection

金沢大学環日本海域環境研究センター生体機能計測研究部

Application of Eddy-Current Testing Technique for High-Density Double-Layer Printed circuit Board Inspection

High-density double-layer printed circuit board (PCB) inspection based on the eddy-current testing (ECT) technique is proposed in this paper. The ECT probe, which consisted of a planar meander exciting coil and spin-valve giant magnetoresistance (SV-GMR) sensor array, is used for this propose. Defects on both the top- and bottom-layer of the high-density double-layer PCB are examined by the ECT technique with scanning over either the top or bottom layer. The characteristics of the proposed ECT probe for high-density double-layer PCB inspection are studied. The inspection results of the high-density double-layer PCB model verify that applying the ECT technique enables identification of the defects of both the top and bottom layer with one-side scanning