Characterization of carbonaceous films deposited on metal substrates by liquid-phase electrodeposition in methanol

In this study, we report the characterization of carbonaceous films deposited on metal substrates by liquid-phase electrodeposition in methanol. The characterization of carbonaceous films by electrodeposition was examined by means of Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), electron energy loss spectroscopy (EELS), secondary ion mass spectrometry (SIMS), atom probe (AP) and high resolution-elastic recoil detection analysis (HR-ERDA). From these results, it was found that the films deposited on the metal substrates were composed of the sp² and sp³ carbon contents, of which the ratio was about 7:3. Furthermore, the films by electrodeposition contained much hydrogen. The hydrogen contents in the surface were about 60 at.% and those in the subsurface were a few 10 at.%.     

Guided-mode resonant grating filter with an antireflection structured surface

We describe a new structure of guided-mode resonant grating (GMRG) filters with low sideband reflectance. This GMRG filter consists of a high-index thin film on an antireflective structured surface called "moth-eye structure." Since the high-index film undulates along the surface structure, the film acts as a modulated optical waveguide. An incident light wave satisfying a resonant condition is reflected by the GMRG filter, and nonresonant light waves pass through the filter. This GMRG filter is valid for reducing reflection of nonresonant light waves in a wide spectral range. The resonant reflection of this new filter was investigated by numerical calculation based on an electromagnetic grating analysis. In the case of a triangular antireflective surface structure whose thickness is 2x greater than its period, the sideband reflectance for nonresonant light waves was lower than 0.5% for TM-polarized light in a wide range of wavelengths.     

Simulation of a zero-dispersion filter monochromator for image-spectroscopic measurements

I propose a novel filter monochromator for image spectroscopic measurements. An aberration-corrected double monochromator that I reported on previously [Appl. Opt. 36, 7114-7118 (1997)] is modified for use in a zero-dispersion mode. An incident image on the entrance aperture is focused onto an imaging detector attached on the exit focal plane with a spectral bandwidth determined by the width of the intermediate slit. Unlike a conventional interference filter, the spectral bandwidth and its center wavelength are determined arbitrarily while both a low stray-light level and the sharp cutoff characteristics of the wavelength are maintained. To demonstrate the real capabilities, ray-tracing simulations are carried out. I also discuss the problem of wavelength purity in the spectroscopic image.     

Small polypoid lesions of the gallbladder: differential diagnosis and surgical indications by helical computed tomography

We report the case of a 16-year-old girl who experienced sudden cardiac arrest from ventricular fibrillation, complicating an arrhythmogenic right ventricular dysplasia, a rare heart muscle disorder, occurring typically in young adults, characterized by a fibrofatty replacement of the right ventricular myocardium. Symptomatic ventricular arrhythmias are frequent, and sudden death has been reported. In our case, diagnosis of arrhythmogenic dysplasia was based on the association of one major criterion and two minor criteria as suggested by the relevant task force. In contrast with most other reports, the chest ECG did not display the typical features. An automatic transvenous pectoral cardioverter-defibrillator was implanted. The authors emphasise that juvenile forms are more exposed to ventricular fibrillation and sudden cardiac death, and consequently require the early detection of the disease. Family cases have been described and the occurrence in one individual must lead to investigations in the relatives.     

Input system for part model in CAD from coloured hand-written illustration with use of ITV

An input system for CAD is developed to construct a part model within a computer from a hand-written sketch. The sketch is drawn based on the technical illustration method. The shape of the input part is constructed by the combination of cuboids and cylinders at present. A coloured illustration is adopted for the ease of the shape recognition and for the input of the technological information.

The illustration is fed into the computer via a black and white ITV. Colours are identified referring to the brightness of the input image. The constitutive bodies, the geometric element with the technological information and the content of the technological information are recognized through image processing such as noise filtering, thinning of the contours, detection of lines and so on. The input system outputs a set of commands to the modelling system. The integrated part model which includes not only the geometrical information but also the technological information of the part is constructed by the connected modelling system CIMS/MODE.

The combination of the input system and the modelling system can support the designer to construct the detailed part model within the computer effectively. It is expected to extend the ability of the input system to identify general hand-written illustrations so that the input method will be more practical and useful.     

Printed Low Velocity Delay Lines for Cathode Readout of Proportional Chambers

A new type of flat delay line was developed which has a low propagation velocity and very good delay to rise time ratio. It can be constructed by printed circuit techniques without crossovers. The magnetic loops of a shifted periodic structure yield high inductance per unit length. Geometric scaling factors are shown. This line, forming the cathode plane of a proportional chamber, allows simultaneously, a satisfactory induced signal and the readout of the second coordinate by time delay without disturbing the electric field configuration around the anode. Optimization of position resolution vs. noise is discussed. Experimental results are shown. Other properties of such delay lines are discussed.     

Measured resonance characteristics of a 2-ghz-fundamental quartz resonator

I fabricated an inverted-mesa AT-cut quartz resonator in which the thickness of the vibrating area was adjusted to 0.6 /spl mu/m by wet etching, and I demonstrated the excitation of a fundamental thickness vibration of 2.074 GHz. This main mode was inductive, and Q was 1037. However, all inharmonic modes were capacitive.     

Purification and characterization of rice alpha-glucosidase, a key enzyme for alcohol fermentation of rice polish

Alpha-glucosidase, a key enzyme for nuka-sake brewing, was purified from Oryza sativa cv. Yamadanishiki, which is widely used for sake brewing. The molecular weight of the purified enzyme was 95 kDa. The optimum pH and temperature were 4.5 and 55 degrees C, respectively. The substrate specificity differed from that of Oryza sativa cv. Shinsetsu, which is a variety of rice consumed as a cereal. The extraction of alpha-glucosidase from the rice was stimulated by lactic acid, which suggests that lactic acid plays an important role not only in preventing bacterial contamination, but also in stimulating the parallel fermentation that occurs in nuka-sake brewing.     

High-Speed X-Cut Thin-Sheet LiNbO3 Optical Modulator With Folded Structure

We propose a small-footprint X-cut thin-sheet lithium niobate optical modulator with high-speed and low-driving-voltage characteristics. Since an optical waveguide is folded by a mirror placed at one edge of the modulation chip, the chip can be shortened by about half. In addition, a wide modulation bandwidth can be achieved, because the path-length difference between the optical waveguide and the coplanar-waveguide (CPW) electrode is decreased to as short as possible by placing the CPW electrode as far as possible along the optical waveguide in the folded portion, and the microwave effective index is set to realize effective velocity matching between the lightwave and the microwave. A small footprint of 1.78 times 29 mm, a low half-wave voltage of 2.0 V at dc, and a 3-dBe modulation bandwidth of 20 GHz were obtained.     

Preparation and properties of carbon dental implant with fine rahmen surface layer

Blade- and tooth-root-form carbon dental implants were prepared by fixing fine Rahmen surface (FRS) layers of carbon fabric on a carbon fiber-reinforced carbon (CFRC) core. The fixing was successfully performed through the low-temperature deposition of pyrolytic carbon using cis-1,2-dichloroethylene as the raw material. The resultant implants showed flexural and compressive strength more than 150 and 100 MPa, respectively. The outer part of this FRS layer contained many pores ranging from 30 to 300 μm in diameter and 40–75% in volume fraction.New bone was generated in the open pores after being embedded in the femur of a monkey for 6 months. The shear strength of the embedded implant vs bone interface was 15 MPa. On the other hand, the blade-form FRS implant in the mandible of a monkey gave a locking system consisting of “bone-collagen fiber-calcified layer” after two years under a masticating pressure. The latter is very similar to the natural tooth system.