bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrasonic Image Processing Using a Three-Dimensional Median Filter
Authors: Mochizuki Takashi , Ito Masayasu , Tachikawa Kenkichi
Published: March 2014

This paper describes the advantages of image processing using a three-dimensional (3-D) filter. The filter algorithm is proposed and then the effects of the filter are shown by way of a numeric simulation and experimental results. The results show that the filter reduces ultrasonic noise echoes, while preserving echo information of 3-D structures in the human body.
A Mechanical Scanning Probe Magnified Steering Angle with an Acoustic Lens
Authors: Kondo Toshio , Kishimoto Shinji , Sato Yutaka
Published: March 2014

A mechanical sector scanning probe magnified steering angle with an acoustic lens is proposed. Chlorotrifluoroethylene oils of moderate molecular weight are used as medium for the lens. The propagation velocity of the medium can be reduced to 0.58 that of the human body with the same acoustic impedance as the body. Steering angle of the acoustic beam to the transducer motion has been magnified over 1.5 times and thus a probe with a small acoustic window achieved.
Pressure Measurement Using Ultrasonic Resonance of Microcapsules
Authors: Watanabe Mikio , Chihara Kunihiro , Shirae Kimisuke , Ishihara Ken , Kitabatake Akira
Published: March 2014

This paper describes non-invasive pressure measurement using ultrasonics. We used the method to examine the acoustic characteristics of elastic microcapsules which are dependent on the surrounding pressure with the following results: 1) The frequency characteristics of a transmission wave passing through elastic microcapsules are linearly related to the pressure. 2) The resonance frequency of elastic microcapsules depends on the material. We are therefore able to obtain the pressure by measuring certain acoustic parameters.
Ultrasonic Absorption in a Binary Mixture of Nitrobenzene/n-Hexane over the Frequency Range of 0.2 MHz–3 MHz
Authors: Inoue Naoki , Takaoka Hajime , Kato Masahiko , Hasegawa Takahi , Matsuzawa Kiichiro
Published: March 2014

The ultrasonic absorption coefficient α has been measured in a critical binary mixture of nitrobenzene/n-hexane over the ultrasonic frequency f of 0.2–3 MHz. The temperature dependence of α/f
2 in a binary mixture is remarkably larger at low frequency than that at high frequency. Frequency dependence of critical absorption at critical temperature T
c has been measured and discussed by the theory of Ferrell and Bhattacharjee (FB).
The absorption relative to critical absorption at T
c has been plotted as a function of the reduced frequency and also compared with the scaling function by the theory of FB.
Nondestructive Profiling of Transistor-Chip under Bias Application by Electron-Acoustic Microscopy
Authors: Takenoshita Hiroshi
Published: March 2014

In electron-acoustic microscopy (EAM), the electron acoustic signal was amplified with a two-phase lock-in amplifier and the phase signal was calculated from the two-output (in-phase and out-phase) signals of the amplifier using a personal computer. Nondestructive profiling of an Si transistor-chip (Tr-chip) under bias application was attempted by EAM using the phase images (PhIs) obtained. It was found that (a) dislocation lines were presented in the base layer which underlay the surface Al electrode (3 µm thick) of the specimen, and (b) PhI changed with bias conditions. The distribution of dislocation lines was investigated.
Relationship between Regularity of Scatterers' Distribution and Speckle Appearing on Ultrasonic Echograms
Authors: Ohya Akihisa , Kashioka Junji , Nakajima Masato
Published: March 2014

The relationship between the regularity of the scatterers' distribution and the statistics of interference patterns such as the speckle appearing on ultrasonic 2-dimensional echograms is examined. Assuming that the phantoms are constructed from the point scatterers whose distribution is both regular and random, computer simulation is performed in which the degree of randomness is a parameter. It is found that the degree of the regularity of the scatterers' distribution can be estimated from the signal to noise ratio of the echogram when the density of the scatterers is known.
Separate Estimation of Mean Spacings and Irregularities of Point Scatterers
Authors: Kikuchi Tuneo , Kiryu Shogo , Sato Sojun
Published: March 2014

Some random media can be expressed by an aggregation of point scatterers. This paper describes the separate estimation of mean spacings and irregularities of these point scatterers by a combination of two methods. The first method estimates the mean spacing of point scatterers by measuring the power of the scattered waves, while the second method estimates the mean spacings and irregularities together by analyzing the power spectrum shape with fractal theory. The estimation methods are then confirmed by experimental results.
Computer Simulation of Laser-Generated Ultrasonic Wave by Finite Element Method
Authors: Nakayuki Toshiyasu , Takahashi Kunikazu
Published: March 2014

We have developed computer programs which are able to clarify the mechanical generating process and propagative process of thermoelastic ultrasonic waves in a solid using pulsed lasers. This paper presents numerical results for elastic wave stresses versus parameters of the laser pulse exciting them. A comparison of the longitudinal waveform is given by analytical solution and finite element solution in a one dimensional problem, and the properties of wave propagation are described for longitudinal and transverse waves in a two dimensional problem.
Photoacoustic Measurements of Phase Transitions in Sn–Bi Alloys
Authors: Kojima Seiji
Published: March 2014

In pure Sn specimens, the temperature dependence of photoacoustic signals shows remarkable change only in the immediate vicinity of the melting point, whereas in Sn–Bi alloys, such remarkable change occurs in the wide temperature range between the solidus and the liquidus. The frequency dependences of photoacoustic signals have also been measured in the frequency range from 1 Hz to 200 kHz. It is found that the dispersion of the photoacuostic anomaly at the melting of Sn changes remarkably by the addition of Bi. This result strongly suggests that the interface becomes irregular as the composition of Bi increases.
Crosstalk in Integrated-Optic Matrix-Vector Processor Using Acoustooptic Effect
Authors: Goto Nobuo , Miyazaki Yasumitsu
Published: March 2014

Crosstalk in an integrated optic matrix-vector multiplier using collinear acoustooptic interaction is discussed. An acoustic crosstalk between adjacent acoustic waveguides is measured to be ∼-3 and \lesssim-20 dB for the waveguide separation of 125 and 250 µm, respectively, at 214 MHz. Theoretically, the crosstalk can be suppressed to less than -25 dB for frequencies \gtrsim150 MHz with the separation of 200 µm. Optical crosstalk caused by the mode conversion along branches is also investigated.
Ultrasonic Behavior of Salol during Melting and Solidification Processes
Authors: Kamioka Hiroaki
Published: March 2014

A new ultrasonic cell was developed for measuring the ultrasonic velocity and attenuation of a sample while observing the condition of the sample from outside the cell. This cell was used in the measurement and observation of Salol in the range between the room temperature and 80 °C, including the melting temperature. Elastic and anelastic data near the melting point are reported and some of the obtained results are discussed.
Ultrasonic Attenuation in Single Crystals of Titanomagnetite
Authors: Kawai Yoriyoshi
Published: March 2014

The acoustic losses in single crystals of titanomagnetite (Fe3-x
Ti
x
O4 in the composition range 0.2≤x≤1) have been studied in the temperature range of 130–520 K by applying longitudinal vibrations of 130, 150 and 200 kHz. Loss peaks were observed in the vicinity of 140, 190 and 480 K with activation energies of 0.08, 0.16 and 0.83 eV, respectively. Two peaks at 140 and 190 K are regarded as stress-induced relaxations of electrons between iron ions on octahedral sites: the first one by hopping between Fe ions and the second one by hopping between Fe2+ and Fe3+ ions with a Ti4+ ion as nearest neighbor. The peak at 480 K is ascribed to the exchange motion of Fe and/or Ti ions and their vacancies on octahedral sites.
Computer Simulation of Conduction and Propagation of Phonons
Authors: Ozawa Satoru , Hiki Yosio
Published: March 2014

Simulations based on the molecular dynamics method have been applied to the transport of a wave packet (acoustic phonons) and a random packet (thermal phonons) along one-dimensional homogeneous and layer-stacked mass-spring chains. Propagation of acoustic phonons (sound) and thermal phonons (heat pulse) accompanying the phonon dispersion can be seen in the homogeneous chain. In the stacked chain, localized phonons within a layer exist together with travelling phonons. The former gradually diffuse out from the layer as time elapses, and the latter propagate with the speed of sound.
Paul Langevin and the Birth of Ultrasonics
Authors: Lewiner Jacques
Published: March 2014

Nature has given some examples of ultrasonic applications for instance with bats or other animals. The first developments of human ultrasonic techniques appeared between 1910 and 1925. The fast progresses which could then be observed were the result of a combination of three factors: the need for underwater detection, the perception of principles which could be used and the availability of new materials and products. Paul Langevin the man who understood these elements, who produced the first systems and who made many discoveries in this field, was then a young physicist. He had been open to the new concepts, subject of many discussions at that time, on matter and electromagnetism. He had been taught in Paris by Poincaré, Brillouin, Perrin and Mr. and Mme Curie. He had visited Cambridge where he had worked with Rutherford, Wilson and Townsend. In 1915 Paul Langevin demonstrated in a famous sink used as a water tank at Ecole Supérieure de Physique et de Chimie Industrielles of the City of Paris, that it was possible to produce and detect ultrasonic waves in water. The emitter was a condenser and the detector a torsion pendulum. One year later, in 1916, experiments were carried in the river Seine and in 1917 he used piezoelectric quartz as emitter, then as receiver. Experiments were made in the South of France in Toulon where the French Navy started to install experimental ultrasonic detection systems on ships. In this paper we will recall Paul Langevin's environment which led to this discovery and describe the various steps between the first experiment in Paris and the tests by the Navy. We will also present a rather unknown aspect of Paul Langevin's personality in relation with the various procedures that he followed to protect, patent and defend his inventions.
Stable Parametric Amplification Using Elastic Microcapsules Placed in Silicone Rubber
Authors: Asada Takaaki , Watanabe Yoshiaki
Published: March 2014

To realize a stable parametric amplification, elastic polymer microcapsules are applied instead of microscopic gas bubbles. Small quantities of the microcapsules are compounded with the silicone rubber, and the mixture is formed into a cylindrical shape as a sample of a nonlinear device. The device is located on the sound-field where the finite amplitude sounds of two near frequencies are trasmitting. It is experimentally observed that the strong nonlinear vibration of the spatially fixed microcapsules generates a stable difference-frequency sound with high efficiency and wide frequency range.
Measurement of Charge Distributions in Coaxial Cable Using the Pulsed Electroacoustic Method
Authors: Yasuda Masataka , Ito Masanori , Takada Tatsuo
Published: March 2014

The accumulated space charge distribution in the insulating material of coaxial cable was measured by the pulsed electroacoustic method. PVDF film was used for detecting the acoustic signal which has the information of space charge distribution. PVDF was bent easily for the coaxial surface of the cylindrical sample. We will discuss the transfer function of the measurement system in the frequency domain to obtain the resolution of this measurement system.
Measurement of Sludge Inside a Fuel Tank by Ultrasonic Pulse in a Heat Engine Plant
Authors: Ogata Masaki , Koizumi Syouzi , Nii Ken-iti , Mitani Sigeki
Published: March 2014

We developed a system to measure shape and amount of sludge sedimentation in a tank using an ultrasonic pulse scanned in the oil tank. Measurement of the amount of oil sludge by ultrasonic pulse requires basic parameters such as sound velocity and surface scattering strength; we therefore measured these parameters. Two experimental formulae of the sound velocity for LPP (low-viscosity oil) and HPP (high-viscosity oil) were obtained. V(LPP)=1483.4-3.48T and V(HPP)=1580.4-4.20T, where T is temperature of the oil in the tank. Characteristics of surface scattering strength depending on incident angle were also measured.
Radiation of Whispering Gallery Mode from Smooth Concave-to-Convex Boundary
Authors: Ohta Seigoh , Ishihara Toyohiko
Published: March 2014

We examine propagation phenomena of whispering gallery mode along the smooth concave-to-convex boundary. A theory is developed which smoothly patches a parabolic equation for the transitional region near the inflection point onto confined whispering gallery mode on the concave side and onto creeping wave on the convex side. Numerical results for the dominant mode confirm the analytical features of the theory, and reveal clearly the radiation of beam-like wave and the excitation of creeping wave on the convex side.
Radiation of an Asymmetric Ultrasonic Pulse in Water by Wave Synthesis Method
Authors: Mogi Ryuta , Endoh Nobuyuki , Hashizume Yoshiyuki , Aoki Takayuki
Published: March 2014

Fragmentation calculus techniques using shock waves are now being used in the medical field. Any of these methods is preferable to abdominal surgery for a human being. Large negative sound amplitude pulses, however, can potentially cause problems such as internal hemorrhage or pain in a human body. The goal of this study was the development of a means to project a unipolar pulse without negative sound pressure which can suppress cavitation. We improved a waveform synthesis method using an inverse filtering method so that an asymmetric pulse whose P+ to P- amplitude ratio was very high was projected in water.
Reconstruction of Acoustic Impedance Distribution of Functionally Gradient Materials by Using Reflection Impulse Response
Authors: Kuwahara Osamu , Wang Ning , Ueha Sadayuki
Published: March 2014

The acoustic impedance distribution of functionally gradient materials (FGM) in which the impedance change gradually along a certain direction is to be reconstructed. Based on the formulation by Howard, the impedance of Al–SiC structured FGM is successfully reconstructed by measuring the acoustic reflection impulse response, and compared with the SAW velocity, show a good correspondence between the two quantities. Ni–ZrO2 structured FGM is also examined as a direct scattering problem.
Experimental Studies on Ultrasonic Measurements of Scattering Media by Using Wavelet Transform
Authors: Kikuchi Tsuneo , Sato Sojun
Published: March 2014

This paper describes the application of wavelet transform for a high resolution ultrasonic measurement. Wavelet transform is one of the methods of time-frequency analysis and is suitable for finding abrupt changes in the wave form. We have been trying to apply this method for detecting positions of point scatterers in random media, and it was found by calculations and experiments that this method can be used for characterization of random media.
Ultrasonic Measurement of Cylindrical Objects Making Use of Ray Tracing
Authors: Nagai Keinosuke , Aoki Fumio
Published: March 2014

This paper discusses an improvement of the time-of-flight method to measure the acoustic velocity in bone. As the first step we consider the thighbone and assume it to be isotropic coaxial cylinder. The measurement of the outer and inner radii of the cylinder as well as the acoustic velocity are studied. These parameters are obtained by finding the ray-path which fulfills the time-of-flight measured. In the experiment we examined two acrylic cylinders first and then a thighbone of cattle. The results seem to be reasonable, though there are some problems left.
Detection of Compressed Pulse Signals by Processing Energy Distribution Ratio
Authors: Shinohara Genta , Sasakura Toyoki
Published: March 2014

A compressed pulse signal obtained when a linear FM signal has gone through a matched filter has a typical waveform of a sampling function. This means that energy of a compressed pulse signal is concentrated near its center peak as is the case with the sampling function. Taking into account this characteristic, we estimated energy distribution of a compressed pulse signal from energy distribution of the sampling function. It has been confirmed that, compared with the conventional method which detects amplitude components, this new method of compressed pulse signal detection provides an improved detecting ability even when the compressed pulse signal is in a status expressed by a cross-correlation function due to underwater propagation loss or phase distortion caused by multipath propagation.
Multiple Scattering and Acoustic Shielding Effect of Parallel Pipes in Water
Authors: Ohbayashi Kazuhiro , Kikuchi Toshiaki , Hasegawa Akio , Nakanishi Toshiyuki
Published: March 2014

The sound pressure scattered by a water-filled pipe, which does not require a special device to protect it from hydrostatic pressure, is calculated theoretically. Transmission loss (TL) of a line array of parallel water-filled pipes is measured to experimentally determine the acoustic shielding effect for 6–100 kHz in water. The peak frequency of the measured TL is similar to that of pressure scattered by a water-filled pipe. TL increases by multiple scattering effect as the space between the pipes narrows. This finding is considered useful in the designing of an acoustic shielding device under high hydrostatic pressure in water.
Detection and Imaging of Subsurface Microcracks in Silicon Wafers Using Photoacoustic Microscope
Authors: Nakata Toshihiko , Kembo Yukio , Kitamori Takehiko , Sawada Tsuguo
Published: March 2014

Photoacoustic imaging of subsurface microcracks in silicon wafers and modulation frequency response of photoacoustic signals detected at the cracks are described. 30 nm wide cracks 12 µm below the surface of a wafer have been successfully detected. The results indicate that amplitude images obtained from different frequencies represent the distribution of the thermal impedance which is increased by cracks at a depth corresponding to the thermal diffusion length. Cracks can be clearly detected by a phase image which represents the distribution of the phase delay sensitive to the thermal discontinuity at the cracks.
Acoustic Properties of Plastics for Applications to Probes of an Ultrasonic Diagnostic Instrument
Authors: Kondo Toshio , Kishimoto Shinji , Sato Yutaka
Published: March 2014

The sound velocity of 78 commercial plastics have been measured at a frequency of 2 MHz in the room temperature for evaluation of transducer window materials. The acoustic impedance of these materials are derived from the measured values of the sound velocity in addition to the density. The results obtained suggest that some types of polymethyl pentene, ethylene-vinyl acetate and polyetherblockamide are similar to human body in acoustic impedance. By using these materials an excellent acoustic transducer window in an ultrasonic diagnostic instrument is indicated.
A Simulation Model for B-Mode Imaging
Authors: Hashimoto Masahiko , Ueno Shin-ichiro , Yano Tsutomu , Sato Jun-ichi , Kawabuchi Masami
Published: March 2014

Ultrasonic B-mode images, as the output of diagnostic ultrasonic imaging systems, are the results caused by acoustic properties inside the human body and a number of acoustic or electrical processings by equipment. In order to estimate a B-mode image and extract useful information for diagnosis, research in the new methods is necessary so that B-mode images can be analyzed quantitatively. For the first step in the development of such new techniques, a simulation model for B-mode imaging was developed. This paper describes the structure of the simulation model studied, and presents some calculated B-mode images.
Elastic Constants of a Cubic Crystal Grown in a High-Pressure Diamond Anvil Cell
Authors: Sasaki Shigeo , Katoh Satoru , Shimizu Hiroyasu
Published: March 2014

The acoustic velocities of a pressure-induced crystalline hydrogen sulfide (plastic phase, fcc) in a diamond anvil cell (DAC) were measured as a function of rotation angle φ by means of Brillouin spectroscopy. The best fitting of the angular dependence of the acoustic velocities between the experimental values and the calculations by the modified Every's expression for elastic waves of arbitrary direction, yields the evaluation for the orientation of the cubic crystal grown in the DAC, and the determinations of the refractive index, the density and the elastic constants under high-pressure.
Load Resistance Characteristics of LiNbO3 Piezoelectric Transformers
Authors: Sato Masuji , Ueda Masanori , Hasegawa Hiroshi , Wakatsuki Noboru
Published: March 2014

We studied a single crystal LiNbO3 piezoelectric transformer composed of 140° rotated Y plate that uses the piezoelectric transverse effect and longitudinal vibration. When driven with a constant voltage, the dependence of the voltage transformation ratio depends remarkably on load resistance. When the load resistance is above about 10 kΩ, the voltage ratio increases in proportion to load resistance in an ideal case.
The transmission characteristics we measured closely match the calculated value when the elastic loss at the support and the floating capacitance of the electrodes are considered.
A Design Method for Micro-Mechanical Filters with Quarter Wavelength Elements
Authors: Satoh Hiroaki
Published: March 2014

Length expander type and thickness expander type micro-mechanical filters are proposed in this paper as attractive elements for an on-chip structure forming. The design principles have been theoretically studied by using a distributed constant circuit design theory. As the result, it is clarified that the method of inserting additional step elements in the middle of the filter is valid for solving the actualization problem of a large impedance step and a filter with the fractional bandwidth of less than 3% is realizable in a VHF and UHF band.
Control of Second Order Temperature Coefficient of SAW Propagating in Thin Film Layers
Authors: Nakagawa Yasuhiko , Yoneda Toshimaro , Hasegawa Kazuhiko , Hosaka Keiko
Published: March 2014

This study proposes the control method of the 1st- and 2nd-order temperature coefficients of two-layer substrate composed of ZnO and Ta2O5 thin films which have the 2nd-order temperature coefficients of delay time with the signs opposite to each other. As a result, a stable SAW substrate of [Ta2O5/ZnO/Fused quartz] showing the 3rd-order characteristics was developed.
Near Infrared Photoacoustic Spectra of Deep Levels in GaAs Grown by Liquid Encapsulated Czochralski Method
Authors: Fukuyama A. , Ikari T. , Miyazaki K. , Maeda K. , Futagami K.
Published: March 2014

Piezoelectric photoacoustic measurements on semi-insulating (SI) and n-type GaAs were carried out at 90 K. A distinctive peak at 0.92 eV and a hump near 1.2 eV have been observed for the SI samples. By comparing with the optical absorption and the electron photoionization cross section spectra, it is considered that these features are due to the electron transition involving deep EL2 defect levels. The present experimental results show that the PA spectroscopic technique is a novel and a useful tool to characterize the deep levels in semiconductors.
Development of Diagnosis System for SAW Devices Based upon Spectrogramme Analysis
Authors: Koike Masakazu , Shiokawa Jun-ichi , Hashimoto Ken-ya , Yamaguchi Masatsune
Published: March 2014

The paper describes the development of a simple but effective diagnosis system for SAW devices based on one of the time-frequency distributions, spectrogramme analysis. The system is realised by employing a personal computer, auxiliary memories and some input/output devices, by which SAW device response measured by a vector network analyser is data-processed, and the result is visualised to be displayed on a CRT. The system was applied to the analysis and identification of the second-order effects in SAW devices, and some visualised results were demonstrated.
IIDT Type Low-Loss SAW Filters Using Withdrawal-Weighted Transducers
Authors: Yatsuda Hiromi , Takeuchi Yoshihiko , Horishima Taira , Yamashita Kazuo
Published: March 2014

This paper describes a method of designing IIDT SAW filters with suppressed sidelobes and reduced insertion loss. The method employs withdrawal-weighted transducers which have almost the same frequency response in pass band and different trap-frequencies in stop bands.
An 880 MHz filter was designed and fabricated according to the proposed method. The sidelobe suppression of 25 to 35 dB, the minimum insertion loss of 1.6 dB, and the 0.5 dB bandwidth of more than 20 MHz were realized.
WDM Optical Switching Characteristics in Collinear Acousto-Optic Module for Photonic Switching System
Authors: Goto Nobuo , Miyazaki Yasumitsu
Published: March 2014

Integrated-optic collinear acousto-optic (AO) switches for WDM photonic switching are discussed. Architectures of wavelength-selective matrix switches for photonic switching and issues on integration of switches are discussed. Optimum switch structures on LiNbO3 substrates are studied from a view point of the AO coupling efficiency. To increase the WDM density, a method to suppress the sidelobes in wavelength filtering characteristics is proposed. The sidelobe is decreased to -26.5 dB from -9.3 dB by this method.
Revolution Speed Characteristics of an Ultrasonic Motor Estimated from the Pressure Distribution of the Rotor
Authors: Hirata Hiroshi , Ueha Sadayuki
Published: March 2014

Using a two-dimensional elastic contact theory, the pressure distribution on the area of contact between the rotor and the stator vibrator of an ultrasonic motor is calculated. In this calculation, the stator vibrator and the rotor are assumed to be a rigid body and an elastic half-space, respectively. The no-load revolution speed of the motor using the calculated pressure distribution is estimated, and is compared with the measured speed. As a result, it is proved that the revolution speed can be estimated by using the calculated pressure distribution if the assumption is satisfied.
Piezoelectric Actuator and Step-Up Voltage Circuit for an Optical Switch
Authors: Ueda Masanori , Sawada Hisashi , Hasegawa Hiroshi , Wakatsuki Noboru
Published: March 2014

A compact, multimode-fiber optical switch has been developed using a piezoelectric actuator to achieve fiber movement with less loss variation. The actuator is constructed of a bending displacement piezoelectric plate using a LiNbO3 (LN) with a polarized inversion layer, as developed by Shimizu, Nakamura, et al.
1) The optical coupling support is formed from a material similar to the actuator to improve temperature dependent loss-characteristics. The optical switch contains a step-up voltage circuit which drives the actuator allowing for smaller device geometory so that the switch can be mounted on a PC board.
Development of Powerful Airborne Ultrasonic Transmitter for Robot Metrology
Authors: Aoyagi Seiji , Kamiya Yoshitsugu , Okabe Sakiichi
Published: March 2014

An airborne ultrasonic transmitter which uses an electric spark discharge was developed for robot metrology. By inserting a condenser of a few hundred picofarads to the secondary side of an ignition coil in the electric circuit of the transmitter, the sound pressure of the radiated ultrasonic pulse becomes about ten times as strong as the case in which the condenser is not inserted. An ultrasonic ranging system which uses this transmitter was also developed.
Frequency Response of a Piezoelectric Polymer Film Hydrophone and an Elastic Wave Induced on the Backing Surface
Authors: Nakamura Yasuhiro , Otani Takahiko
Published: March 2014

The Frequency response of hydrophones using a thin film of piezoelectric polymer of P(VDF-TrFE) as an active element is investigated. An irregularity in the response for which can not be theoretically accounted is always observed. We have verified by means of optical visualization or schlieren method, that the Rayleigh type wave excited on the backing surface of the hydrophone brings a radial resonance and shows a phenomenon of irregularity on the frequency response.
Ultrasonic Vibration Press of Powder Using 20 kHz Upper and Lower Vibration Punches and a Vacuum Compacting Die
Authors: Tsujino Jiromaru , Suzuki Haruo
Published: March 2014

Ultrasonic vibration press of metal and piezoelectric ceramic (PZT) powder under vacuum condition is studied. Longitudinal vibration punches of 20 kHz vibrating in anti-phase or in-phase mode and a vacuum compacting die are used. Using an upper and a lower vibration punch and a vacuum die simultaneously, the increment of compact density becomes larger than that of density using only vibration punches or a vacuum compacting die. The hardness of the copper and piezoelectric ceramic (PZT) compacts obtained by this method was about double that of the compacts obtained by only static compacting pressure under 147 MPa static pressure.
Tunneling Acoustic Microscopy
Authors: Takata Keiji
Published: March 2014

This paper describes tunneling acoustic microscopy (TAM), which is based upon a scanning tunneling microscopy (STM) and a technique for detecting an acoustic wave. The principle of TAM is to detect fine strains generated in the STM sample. It enhances the features of STM without reducing its ability, and enables us to image nonconducting materials.
Simulated Heat Conduction in Toda Lattices with Inhomogeneous Mass Distribution
Authors: Nishiguchi Norihiko , Takahashi Naoki , Sakuma Tetsuro
Published: March 2014

The validity of Fourier's law is investigated by taking account of the temperature dependence of the thermal conductivity for the one- and two-dimensional Toda lattices with inhomogeneous mass distribution. The thermal conductivity is found to be proportional to the inverse of local temperature for both the one- and two-dimensional lattices. Fourier's law is confirmed by excluding the non-diffusive energy flow from the total energy current.
Thermal Diffusivity of Semiconductors Evaluated by Differential PPE Method
Authors: Morimoto Jun , Okamoto Yoichi , Miyakawa Toru
Published: March 2014

Differential PPE (photopyroelectric) method is proposed to measure local thermal diffusivity of semiconductors. In stead of signal amplitude vs distance relation, the phase difference vs modulation frequency characteristics are measured. Differential PPE method reflects the local thermal property irrespective to the generated heat by absorbed light. The thermal diffusivity of polycrystalline CdS detected by PVF2 transducer was found slightly lower compared with that of single crystalline CdS.
Velocity of Sound in and Elastic Properties of Rb2O–B2O3 Glasses
Authors: Kodama Masao
Published: March 2014

Ultrasonic velocity in rubidium borate glasses is measured as a function of composition at a frequency of 10 MHz and at a temperature of 298 K, which is found to exhibit a maximum, a minimum, and another maximum in succession as the rubidium oxide content increases. Elastic properties of these glasses expressed by elastic constants such as longitudinal modulus, shear modulus, bulk modulus, and Young's modulus, are discussed in terms of the three dimensional covalent bond in the glass network.
Critical Acoustic Anomaly of a Binary Mixture of Nitroethane and Cyclohexane with Acetone Impurity in the Frequency Range of 0.3–3 MHz
Authors: Inoue Naoki , Murakami Yuichiro , Kato Masahiko , Hasegawa Takahi , Matsuzawa Kiichiro
Published: March 2014

The ultrasonic absorption coefficient a has been measured in a critical binary mixture of nitroethane and cyclohexane (NE/CH) with acetone impurity in the frequency range of 0.3–3 MHz.
The critical anomaly of the ultrasonic absorption in the binary mixture with impurity has been analyzed on the basis of the dynamic scaling function proposed by Ferrell and Bhattacharjee (FB). From this procedure, we have succeeded in estimating the characteristic angular frequency of concentration fluctuation and its impurity effect.
Liquid Sensor Using Two-Port Surface Acoustic Wave Resonator
Authors: Nomura Tooru , Yasuda Tsutomu , Furukawa Shoji
Published: March 2014

A two-port SAW resonator has been designed for a stabilizing element of an SAW liquid sensor. There is increasing use of SAWs for sensors, and most of the works reported on sensors to date are concerning delay lines. In this paper, SAW resonators have been studied in order to reduce an acoustic loss and a distortion of the delay lines. SH type SAWs are excited on a 36° YX LiTaO3 substrate by using IDTs. The two port SH-SAW resonators have been used for sensing the liquid. The sensitivity of the SAW resonance frequency and Q value for the viscosity of liquids have been measured.
Excitation of Hypersonic Waves at Metal/Liquid Interfaces Using Transient Reflecting Gratings
Authors: Harata Akira , Sawada Tsuguo
Published: March 2014

Optical generation of coherent hypersonic waves are first demonstrated at metal/liquid interfaces using the transient reflecting grating technique. Two important acoustic modes are identified: One is the Scholte (or pseudo-Stoneley) mode localized at the interfaces, and its velocity relates to the liquid elasticity within some hundreds of nanometers from the interface; and the other is a longitudinal acoustic mode propagating parallel to the interfaces in the liquids, and its intensity relates to heat conduction from the solid to the liquid.
Studies on Material Evaluation of Metals by Ultrasonic Spectrum Method
Authors: Honjoh Katsuhiko , Masuda Jun-ichi , Sudoh Yoshikazu
Published: March 2014

This paper describes a technique for evaluating structural variations in metal properties by analyzing spectrum distributions of ultrasonic pulse echo wave forms through FFT processing. We have clarified the relationship between spectrum peak frequency and tensile elongation for austenitic stainless steel as well as that between spectrum peak frequency and graphite nodularity for ductile cast iron.
Comparison of EXAFS Spectra at the L Edges
Authors: Chaboy J. , Garcia J. , Marcelli A.
Published: March 2014

In this paper we discuss a new method for direct comparison between L2,3 and L1 EXAFS spectra. A detailed analysis of the basic EXAFS formula leads to a simple relationship between the EXAFS signals at the L3 and L1 edges that includes the total phase-shift difference for the two absorption processes. This relation has been successfully used to perform the comparison of theoretical and experimental data of barium in the cubic BaF2 system.
Charge-Transfer Satellites in Ti 2p XAS and XPS of Ti Compounds
Authors: Okada Kozo , Uozumi Takayuki , Kotani Akio
Published: March 2014

Ti 2p X-ray photoabsorption (XAS) and photoemission (XPS) spectra in formally tetravalent Ti compounds, such as TiO2 and SrTiO3, are analyzed by means of a TiO6 cluster model, where the Ti 3d-O 2p covalency mixing and the multiplet coupling between the Ti 3d and 2p electrons are taken into account. The satellite peaks observed in the Ti 2p XPS and XAS are interpreted as charge-transfer satellites, although they have been ascribed to the exciton satellite due to the excitation from the O 2p to O 3s states so far.
Maximum Entropy Method Analysis of EXAFS Data Using a Specific Criterion to Derive the Prediction Error Filter
Authors: Matsubayashi Nobuyuki , Shimada Hiromichi , Imamura Motoyasu , Yoshimura Yuji , Sato Toshio , Nishijima Akio
Published: March 2014

A new analytical method of EXAFS is proposed by modifying the Maximum Entropy Method (MEM). The appropriate term number (m) of the prediction error filter is derived according to a specific criterion in this work. This newly developed MEM showed a great improvement in both resolution and reliability of the spectra for EXAFS.
Simultaneous Multiple File EXAFS Analysis: Methodology and Application to Buried Ge–Si Interfaces
Authors: Tyliszczak T. , Aebi P. , Hitchcock A. P. , Jackman T. E. , Baribeau J-M. , Lockwood D. J.
Published: March 2014

Procedures for constrained simultaneous non-linear least squares curve fits of multiple EXAFS spectra are described and their advantages discussed. The techniques are illustrated by polarisation-dependent GeK EXAFS studies of buried Ge-Si interfaces in strained layer [(Si)m(Ge)n]p/Si(100) superlattices grown by molecular beam epitaxy (MBE).
Constrained and Restrained Refinement in EXAFS Data Analysis with Curved Wave Theory
Authors: Binsted Norman , Strange Richard W. , Hasnain S. Samar
Published: March 2014

This paper describes methods of constrained and restrained refinement of EXAFS data which provide a means of substantially reducing the number of independent parameters compared to conventional least squares methods commonly used. Constrained refinement allows a major reduction in the number of free parameters for a refinement of a structural model. In restrained refinement, additional structural information from well characterised small molecules is used to provide additional observations in the data analysis.
Quantitative Fluorescence EXAFS Analysis of Concentrated Samples–Correction of the Self-Absorption Effect
Authors: Tröger Larc , Zschech Ehrenfried , Arvanitis Dimitri , Baberschke Klaus
Published: March 2014

The EXAFS amplitudes of concentrated samples measured in the fluorescence mode strongly depend on the detection geometry through the self-absorption effect. Knowing the stoichiometry of the sample, we can fully correct for the self-absorption effect using a simple theory and obtain the true EXAFS. The correction procedure presented here for the Oxygen K-edge EXAFS of NiO is generally applicable and should be the first step in the quantitative analysis of fluorescence EXAFS data of concentrated samples.
The Correction of the Dead Time Loss of the Ge Detector in X-ray Absorption Spectroscopy
Authors: Zhang K. , Rosenbaum G. , Bunker G.
Published: March 2014

The effects of dead time loss of the 13 element Ge detector (Canberra, GL0110), which result from the associated electronics, were studied. Distortions and noise attributable to dead-time losses are found to be substantial even for dilute metalloprotein samples and modest count rates. The dead time loss can introduce two types of non-linear problems into the X-ray Absorption Fine Structure (XAFS) data collection. First, the I0 fluctuation cannot be fully divided out; second, XAFS spectra for concentrated samples can be substantially reduced. The dead time loss calibration showed that the response of the system can be better approximated by the first order approximation of the paralysable and the non-paralysable models rather than the two models themselves. The dead time correction using this algorithm produces satisfactory results with the correction error generally within the statistical error of photon counting. This will permit reliable XAFS data collection at high Incident Count Rate greatly improving the counting efficiency. The dependences of the dead time and the energy resolution on the shaping time of the shaping amplifier were also examined.
EXAFS Studies of Rare Earths and Their Oxides
Authors: Shah Galav , Upadhyaya G. K. , Gupta S. N.
Published: March 2014

An analytical approach for locating the absorption edges based on Fourier transformation of EXAFS data is presented. The chemical shifts of the absorption edges between RE metals and their Oxides calculated using this approach give more accurate results as it eliminates the uncertainty in the location of absorption edges.
Recent Advances in Soft-X-Ray Absorption Spectroscopy
Authors: Chen C. T.
Published: March 2014

X-ray absorption Spectroscopy in the “soft” region has achieved major progress recently. High resolution soft-x-rays with a high degree of linear or circular polarization can now be routinely produced, and high sensitivity soft-x-ray fluorescence detectors are available. Soft-x-ray absorption experiments, recently conducted at the Dragon beamline, are utilized to demonstrate the information that can be obtained on the electronic and magnetic structure of matter, emphasizing the new scientific opportunities offered by these spectroscopic advances.
ELNES Measurement for the Adsorption of Oxygen on Ni(100)
Authors: Hayashi Toshinori , Araki Kiyoaki , Takatoh Shuji , Enokijima Toru , Yikegaki Tetsurou , Tsukajima Jun'ichi , Fujikawa Takashi , Usami Seiji
Published: March 2014

The oxygen K-edge electron energy -loss near-edge structure (ELNES) spectra for NiO and O/Ni(100) system have been measured by using the reflection mode of small-angle scattering. Through comparison between the ELNES and the XANES for NiO, we find that this experimental mode is governed by dipoleallowed transitions. It is demonstrated that the ELNES spectra of O/Ni(100) system depend on oxygen exposure and on the orientation of momentum transfer of a probe electron.
Quick Fluorescence XAFS: A Technique for Recording Fluorescence X-ray Absorption Spectra during Chemical/Biochemical Reactions
Authors: Dobson Barry R. , Hasnain S. Samar , Neu Margarete , Ramsdale Christine A. , Murphy Lorretta M.
Published: March 2014

The Quick EXAFS (QuEXAFS) technique (1,2) provides an alternative way of recording X-ray absorption fine structure (XAFS) data where scan time is minimised by continuous scanning of the monochromator. In contrast to the dispersive technique, QuEXAFS is capable of obtaining data in fluorescence mode as well as in transmission and is therefore suitable for dilute samples. The reduction in data collection time makes it feasible to follow some biochemical or chemical reactions at room temperature with the XAFS technique. We have recently commissioned a QuEXAFS experimental set up on station 9.3 on the 5T wiggler at Daresbury SRS. This station is equipped with a vertically focussing mirror, which in addition to providing extra flux also performs harmonic rejection due to the critical angle cutoff off the mirror reflectivity. The use of the mirror for some harmonic rejection is complemented by the use of a very stable two crystal water cooled monochromator. This provides additional harmonic rejection yet is stable enough to be used without a dynamic harmonic rejection servo, an important consideration for QuEXAFS scans. The monochromator Bragg angle is driven by a dc motor system encoded by a 0.1mdeg encoder. This system can be optimised for constant angular velocity scans and thus is well suited for QuEXAFS and avoids vibrations associated with stepper motors driven at speed. The high flux on the sample together with the use of a high count rate 13 element solid state fluorescence detector (3) have allowed us to obtain quality data on a 5mM solution in less than a minute. Studies have also been carried out on a dilute solution of a transferrin intermediate. We note that this is the first fluorescence QuEXAFS reported and is the lowest concentration for which a XAFS spectrum has been collected in less than a minute. Improvements iii the sample geometry and in the scanning protocol will allow faster data collection on more dilute systems.
Diffraction Anomalous Fine Structure: XAFS with Virtual Photoelectrons
Authors: Bouldin C. E. , Woicik J. C. , Stragier H. , Cross J. O. , Rehr J. J. , Sorensen Larry B.
Published: March 2014

This paper discusses a new x-ray structural technique, Diffraction Anomalous Fine Structure (DAFS) , which combines the long-range order sensitivity of diffraction with the short-range order sensitivity and chemical selectivity of x-ray absorption (XAFS). Because absorption and scattering are related by causality, the absorption information available from XAFS is also accessible from DAFS measurements of the elastic, fixed momentum transfer, Bragg reflection intensities. These DAFS measurements exhibit a fine structure versus photon energy analogous to XAFS. DAFS provides all of the usual information of XAFS: the near neighbor bond lengths, numbers, types and disorders around the specifically excited atoms. In addition, because DAFS unifies all of the capabilities of diffraction and XAFS into a single technique, it provides advantages that neither technique possesses separately: (1) Spatial selectivity. DAFS provides short-range order information about the specific subset of long-range ordered atoms selected by the diffraction condition. (2) Site selectivity. DAFS provides site specific short-range order information for inequivalent sites of a single element. (3) Valence sensitivity. DAFS provides valence specific features in the near edge region.
Optical Luminescence Yield Spectra of CaF2 through X-ray Excitation
Authors: Murata Takatoshi , Harada Katsuyuki , Emura Shuichi , Nomura Masaharu , Bauchspiess Karl Rudolf , Maeda Hironobu
Published: March 2014

Optical luminescence yield spectra of CaF2 through x-ray excitation in the energy region of the Ca K edge (4.0 keV) are reported. Experiments with samples prepared differently – a powder layer, a pellet, and single crystal – at 90 K and 30 K were performed. It is found in the measurements at 90 K that the yield spectrum is similar to the absorption spectrum, but for the pellet and the single crystal the edge jump is inverted. With lowering the temperature to 30 K, the edge jumps become positive for all the samples. Recent results of theoretical simulations of the yield spectra are discussed.
X-ray Excited Luminescence Yield Spectra of NaBr and NaBr:Cu Single Crystals
Authors: Murata Takatoshi , Harada Katsuyuki , Emura Shuichi , Nomura Masaharu , Bauchspiess Karl Rudolf , Maeda Hironobu , Hiraya Atsunari , Watanabe Makoto
Published: March 2014

X-ray excited optical luminescence yield spectra of single crystals of pure NaBr and Cu-activated NaBr are reported. X-rays are scanned at the energy regions of K edges of Br and Na. The yield spectra for the intrinsic luminescence emission band of NaBr at 4.5 eV for both samples and those for the Cu impurity luminescence band at 3.4 eV are compared. The results show that in the NaBr:Cu, both positive and negative edge jumps are observed depending on the monitored emission band. The yield spectra are reproduced with the calculation following our recent phenomenological theory.
Optical Luminescence Yield X-ray Absorption Fine Structures at the Sulphur and Silicon K-edge
Authors: Sham T. K. , Feng X.-H. , Jiang D.-T. , Tan K. H. , Frigo S. P. , Rosenberg R. A. , Houghton D. C. , Bryskiewicz B.
Published: March 2014

Optical luminescence induced by soft x-ray excitation in the vicinity of the S K-edge (∼2472 eV) and Si K-edge (∼1839 eV) in P-31 (ZnS:Cu phosphor) and porous silicon has been studied with an optical spectrometer. The luminescence yield was in turn used, together with total electron yield, to record x-ray absorption fine structures in the near edge region of the corresponding S and Si K-edge. It is found that although the luminescence spectrum of soft x-ray excited P-31 above and below the S K-edge is identical, a small shift is noted in porous silicon at photon energies below and above the Si K-edge and that the luminescence yield (optical photon/soft x-ray photon absorbed) varies significantly depending on experimental conditions and/or the nature of the exciting channel.