bluuebunny/crossref_metadata_2025 huggingface dataset:
Nonlinear regime shifts in Holocene Asian monsoon variability: potential impacts on cultural change and migratory patterns
Authors: Donges J. F. , Donner R. V. , Marwan N. , Breitenbach S. F. M. , Rehfeld K. , Kurths J.
Published: March 2014

Abstract. The Asian monsoon system has been recognised as an important tipping element in Earth's climate. In this work, we apply recurrence networks, a recently developed technique for nonlinear time series analysis of palaeoclimate data, for detecting episodes with pronounced changes in Asian monsoon dynamics during the last 10 ka in speleothem records from 10 caves covering the major branches of the Asian monsoon system. Our methodology includes multiple archives, explicit consideration of dating uncertainties with the COPRA approach and rigorous significance testing for the coexistence of monsoonal regime shifts at multiple locations to ensure a robust detection of continental-scale changes in monsoonal dynamics. This approach enables us to identify several epochs characterised by nonlinear regime shifts in Asian monsoon variability (8.5–8.0, 5.7–5.4, 4.1–3.6 and 2.8–2.2 ka BP), the timing of which suggests a connection to high-latitude Bond events and other episodes of Holocene rapid climate change (RCC). Interestingly, we also observe a previously unnoticed episode of significantly increased regularity of monsoonal variations around 7.3 ka BP, a timing that is consistent with the typical 1.0–1.5 ka return intervals of Bond events. A possible solar forcing of the detected nonlinear regime shifts in Asian monsoon dynamics is suggested by their co-occurence with pronounced minima and strong variability in solar activity. Drawing on a comprehensive review of the Holocene archeological record in the Asian monsoon realm, we find that these regime shifts partly coincide with known major periods of migration, pronounced cultural changes, and the collapse of ancient human societies. These findings indicate that also future transitions in monsoonal dynamics could induce potentially severe socio-economic impacts of climate change.
Impact of a 30% reduction in Atlantic meridional overturning during 2009–2010
Authors: Bryden H. L. , King B. A. , McCarthy G. D. , McDonagh E. L.
Published: March 2014

Abstract. The Atlantic meridional overturning circulation comprises warm upper waters flowing northward, becoming colder and denser until they form deep water in the Labrador and Nordic Seas that then returns southward through the North and South Atlantic. The ocean heat transport associated with this circulation is 1.3 PW, accounting for 25% of the maximum combined atmosphere–ocean heat transport necessary to balance the earth's radiation budget. We have been monitoring the circulation at 25° N since 2004. A 30% slowdown in the circulation for 15 months during 2009–2010 reduced northward ocean heat transport across 25° N by 0.4 PW and resulted in colder upper ocean waters north of 25° N and warmer waters south of 25° N. The spatial pattern of upper ocean temperature anomalies helped push the wintertime circulation 2010–2011 into record-low negative NAO conditions with accompanying severe winter conditions over northwestern Europe. The warmer temperatures south of 25° N contributed to the high intensity hurricane season in Summer 2010.
In Search of the Origins of theOpłatek
Authors: Anderson Claire M.
Published: March 2014

Prompted by the curiosity that the uniquely Slavic Christmas wafer has a Latin-based name in Polish, "opłatek," the author traces archaeological, etymological, and ethnographic clues in search of the history of the opłatek. An indigenous Slavic custom of sharing hearthcakes at the winter solstice may have facilitated the expansion of the western Christian monastic industry of wafer making. The earliest possible dating of the arrival of the word "opłatek" is the high Middle Ages when the western Church established dioceses and monasteries in Poland. The latest possible dating is the late eighteenth century, just decades before renowned Polish ethnographer Oskar Kolberg documented widespread practice of the custom. Between those dates, the sharing of the Christmas wafer swelled in popularity throughout the noble and peasant classes and over a huge geographic territory. Today it is a tradition kept by 97 percent of first-generation Polish Americans.
Many flaked particles caused by impulsive force of electric field stress and effect of electrostriction stress in mass-production plasma etching equipment
Authors: Kasashima Yuji , Nabeoka Natsuko , Motomura Taisei , Uesugi Fumihiko
Published: March 2014

To investigate the mechanism of instantaneous generation of many flaked particles in plasma etching chambers, we study the relationship between particle generation from deposited films and electric field stress acting on the films under mass-production conditions. The particles are formed by stress working as an impulsive force due to rapid changes in floating potential on the chamber walls. The results indicate that Maxwell’s stress and electrostriction stress both affect particle generation in terms of the impulsive force of electric field stress. Although Maxwell’s stress mainly influences the outbreak of particles, the electrostriction stress also acts with considerable intensity.
Ultrasonic Beam Scanning by Frequency Sweep
Authors: Yashiro Ken'ichiro , Nishihara Yoshihide , Ohkawa Sumio
Published: March 2014

A Fourier integral solution to the problem of compressional waves radiated into a semi-infinite fluid half space from an interdigital transducer at the piezoelectric solid-fluid interface is sketched out. The Fourier integral is evaluated asymptotically by the method of steepest descents. This leads to a clear understanding of the ultrasonic beam scanning by changing the frequency. Numerical results are obtained for a PZT ferroceramic material and compared with experimental ones.
A New Method of Exciting Focused Surface Acoustic Waves Using an Interdigital Transducer
Authors: Nomura Tooru , Yasuda Tsutomu
Published: March 2014

Methods of exciting and focusing surface acoustic waves on a sample material are described. In the field of nondestructive evaluation, it is beneficial to excite and focus a surface acoustic wave to detect small cracks on the sample surface. An interdigital transducer deposited on a piezoelectric substrate can excite surface acoustic waves on a sample surface making it useful as an acoustic wave source in a nondestructive evaluation system. In this paper, we describe a new method of exciting focused surface acoustic waves using a Fresnel-phase-plate type interdigital transducer with a gel couplant.
Investigations on an Ultrasonic Piezoelectric Printer
Authors: Sakurai Kikukazu , Suga Michihisa , Inoue Takeshi , Takahashi Sadayuki
Published: March 2014

An ultrasonic piezoelectric printing technology was proposed and investigated. The printing head is composed of a multilayer piezoelectric actuator, operating in stiffened longitudinal mode, two-stage step horns and printing wire. The resonant frequency for the ultrasonic printing head is 146 kHz. The thermoplastic ink, melted by ultrasonic energy, is transferred onto the surface layer of plain rough paper by ultrasonic vibration. This technology realizes more rapid, lower noise and higher quality printing on a wide range of papers than conventional thermal transfer printing technologies. This unique non-impact printing method is useful for a personal desktop printer.
Piezoelectric and Acoustic Properties of Piezoelectric Flexible Composites
Authors: Banno Hisao , Ogura Kohji , Sobue Hideo , Ohya Kanji
Published: March 2014

Piezoelectric and acoustic properties of piezoelectric flexible composites or Piezo-Rubbers which have been developed at NTK-NGK are reported. The frequency dependences and hydrostatic pressure dependences of underwater receiving sensitivities of hydrophone using the Piezo-Rubber are discussed in terms of the properties of Piezo-Rubber materials. Also single pulse acoustic transmitting/receiving responses of the Piezo-Rubber are compared with those of PZT ceramics, PVDF polymer and PZT/polymer 1-3 type composites.
A Theoretical Study of the Characteristics of Leaky-Surface-Acoustic-Wave Filters with Propagation Loss by an Equivalent Circuit Model
Authors: Shimizu Yasutaka , Ozawa Hidetaka
Published: March 2014

Leaky surface waves are very interesting because their temperature stability is extremely high even though a small value of propagation loss must be considered. In this paper, the characteristics of SAW filters on a substrate with propagation losses are theoretically investigated and compared with the ideal properties without losses. The results show that propagation losses are not always disadvantageous for TTE suppression.
Studies on Ultrasonic Butt Welding of Different Metal Plates
Authors: Tsujino Jiromaru , Ueoka Tetsugi
Published: March 2014

Ultrasonic butt welding to join metal specimens end to end is proposed and studied. Using a new ultrasonic butt welding system and a 27 kHz high power ultrasonic vibration source with 6 bolt-clamped Langevin type BLT transducers, welding specimens aluminum plates, anticorrosive aluminum and copper plates (6 mm thick) are successfully welded end to end. The weldments are measured by a scanning electron microscope, an X-ray microanalyzer and a micro hardness tester, and no significant structural change of weldment is found.
Detection and Application of Acoustic Emission in Laser-Enhanced Chemical Etching
Authors: Shiosaki Tadashi , Masuda Hiroshi , Adachi Masatoshi , Kawabata Akira
Published: March 2014

Automatic laser focus adjustment and nondestructive flaw detection on a ceramic surface, as well as monitoring of the laser machining process have been successfully carried out using a system to detect, process and feed back the photoacoustic (PA) signal emitted from the laser irradiated work point during the laser-induced chemical solution etching of ceramics such as PbTiO3, PZT and Mn–Zn ferrite.
Gelation and Ultrasonic Hysteresis in Egg White
Authors: Choi Pak-Kon , Bae Jon-Rim , Takagi Kenshiro
Published: March 2014

Ultrasonic absorption and velocity were measured at 3 MHz in egg white gel. An increase in absorption and a decrease in velocity were observed with time lapse at several aging temperatures ranging from 60 to 80°C. Hysteresis phenomenon was also observed by varying the aging temperature as a parameter. This phenomenon is associated with the memorizing effect of the network structure of protein of the gel. It is demonstrated that the ultrasonic technique is useful for monitoring the gelation process.
Surface Acoustic Soliton in Superlattices
Authors: Saito Osamu , Sakuma Tetsuro
Published: March 2014

A theory of surface acoustic soliton (SA soliton) in superlattice is presented. Following a procedure similar to that of an isotropic continuum presented earlier, the equation for the classical displacement field at the stress free surface can be reduced to the nonlinear Schrödinger equation with a dissipation term. The dispersion relation of the surface phonons which plays an essential role in the modulational instability is investigated for some typical superlattice structures. The possibility of observing the SA soliton is also discussed both analytically and numerically.
Application of Nonlinear Effect to Ultrasonic Pulse Reflection Method –Modulation Characteristics of Received Pulse–
Authors: Fukukita Hiroshi , Ueno Shin-ichiro , Yano Tsutomu
Published: March 2014

An application of nonlinear effect to ultrasonic pulse reflection method is described. With this method, higher frequency probe pulse wave and lower frequency large pressure amplitude pump pulse wave are transmitted along the axis of a coaxially arranged probe transducer and a pump transducer, and are superposed in the propagation medium by precisely controlling the relative phase of these pulses. Frequency characteristics of a nonlinearly modulated probe pulse wave are analyzed, and center frequency shift and change in group delay are obtained. These experimental values are evaluated by a simple analytical method.
Transmission-Reflection Technique for Measurement of Frequency Characteristics of Ultrasound Attenuation Constant
Authors: Soetanto Kawan , Tanaka Motonao , Ohtsuki Shigeo , Okujima Motoyoshi
Published: March 2014

A technique for obtaining the attenuation constant α and its frequency characteristics from the echo signal of a point reflector is proposed. Experiments were conducted using specimens of fine glass balls dispersed in agar and gelatin as an ultrasonic medium. The experimentally obtained value of α was close to the data obtained by relative attenuation technique.
An Estimation Method of Vertical Sound Speed Profile in Mid-Deep Water Using Multipath Propagation
Authors: Hachiya Hiroyuki , Ohtsuki Shigeo , Okujima Motoyoshi
Published: March 2014

Oceanic current is closely related to such sea water structure as temperature distribution. To observe the change of current in mid-deep water, a method of estimating the vertical sound speed profile using multipath propagation is studied. In mid-deep water, sound is propagated by repeated reflection at both bottom and surface. We estimate the reflection loss of the sea bottom in Sagami Bay from the sound transmission experiment data. Then, using a mid-deep water model, we estimate the vertical sound speed profile from travel times of bottom and/or surface reflected rays. Good results show that estimation of the vertical sound speed profile is valid for mid-deep water monitoring.
Automated Marx's Composite Oscillator Method II
Authors: Tateno Hiroto , Iwashita Youichirou
Published: March 2014

In previous work Marx's composite oscillator method was automated for measuring internal friction and Young's modulus. However, this system did not consider the phase control. We added a phase control circuit which keeps the phase between stress and strain constant, thereby maintaining a resonant condition. This improvement enables wide range measurement of internal friction with no phase deviation, and consequently with stability and precision. The stability of this system was analyzed by the automatic control theory. As application, fast and continuous measurement of strain amplitude dependence in NaCl single crystal is described.
Alignment of Ferroelectric Liquid Crystals on a Ferroelectric Transparent Ceramic Plate
Authors: Seki Hidehiro , Uchida Tatsuo , Masuda Yoichiro
Published: March 2014

An alignment technique of ferroelectric liquid crystals (DOBAMBC) on a ferroelectric ceramic plate is described. In the cell with a ferroelectric transparent ceramic plate and a buffed glass plate, electric interactions between ferroelectric liquid crystals and a ferroelectric ceramic plate are thought to be effective for aligning liquid-crystal molecules. The result shows that the liquid-crystal molecules orient perpendicular to the polar direction of the transparent ceramic plate.
Elastic Anomaly of the Tetragonal PLZT
Authors: Sasaki Yukihiko , Yokosuka Masaru , Marutake Masakazu
Published: March 2014

Elastic properties of lanthanum doped lead zirconate-titanate, PLZT (9.8/55/45), were studied by the ultrasonic pulse-echo-overlap technique over the range from -70°C to 100°C including both the paraelectric and the ferroelectric phase. The measured velocities have pronounced changes at the transition temperature.
Angular Rate Detection Utilizing Phase Shift in a Piezoelectric Vibratory Gyro
Authors: Sugawara Sumio , Hwang C. C. , Konno Masashi
Published: March 2014

This paper deals with a new method for estimation of an angular rate applied to a piezoelectric vibratory gyro. The principle for estimation is based on detecting a phase shift of output signal by the applied angular rate. In this method, a stable output signal in the case of no angular rate must be absolutely present, and its phase should be maintained at ±90° to realize the characteristic desired as an angular rate sensor. Moreover, the sensitivity and linearity depend on the amplitude of output signal under no angular rate. Some experiments and simulations by use of the equivalent circuit are done, and the validity of this method is confirmed.
On the Responsibility of Piezoelectric Actuator
Authors: Fujii Hiromitsu , Ohnishi Yasushi
Published: March 2014

A kind of multilayer piezoelectric actuators were manufactured to be able to respond within 10∼100 µsec for pulse field, and examined the pulse responsibility. The response time might be rather strongly dependent on the sample conditions than both of driving voltage and generated strain.
Ferroelectric Pb(Zr, Ti)O3 Thin Films Prepared by Metal Target Sputtering
Authors: Croteau André , Matsubara Shogo , Miyasaka Yoichi , Shohata Nobuaki
Published: March 2014

Lead zirconate titanate Pb(Zr, Ti)O3 thin films have been deposited by rf magnetron sputtering of a multi-element metal target. The metal target design provided the feasibility for controlling the PZT film composition by adjusting the surface areas of Pb, Zr and Ti at the target. The cubic pyrochlore structure has been obtained on low temperature (100 to 300°C) substrate and a perovskite structure resulted by a post deposition annealing at 600°C. The Pb rich film was found to be a requirement for obtaining the perovskite structure after annealing. The dielectric constants and dielectric losses of perovskite films were from 300 to 500 and from 0.02 to 0.2, respectively. From P–E hysteresis loops, the highest remanent polarization measured was 12.5 µC/cm2 where the corresponding coercive field was 90 kV/cm.
Bending Vibrator Consisting of a LiNbO3 Plate with a Ferroelectric Inversion Layer
Authors: Nakamura Kiyoshi , Ando Haruyasu , Shimizu Hiroshi
Published: March 2014

An anti-polarity ferroelectric laminar domain (inversion layer) can be formed in a LiNbO3 plate without applying any external fields by heat treatment at somewhat lower temperatures than the Curie point. A plate with such an inversion layer can be used as a bending vibrator with no bonding layer. This paper reports the characteristics of the bending vibrators. The 137° rotated Y-cut of LiNbO3 is shown to be the optimum plate orientation for the bending vibrators because it exhibits a high transverse electromechanical coupling factor of about 0.51. It is also demonstrated that a bending vibrator fabricated using 128° rotated Y-cut LiNbO3 has a capacitance ratio as low as 7.82, which is slightly higher than the theoretically predicted value.
A Unidirectional SAW Transducer with Different Finger Pairs between Sending and Reflecting Electrodes
Authors: Yamada Jun , Fujita Yuuji , Shiba Takashi , Toyama Tatsuro
Published: March 2014

An intentionally imperfect unidirectional transducer has been studied for SAW TV IF filter. It is constituted of different finger pairs between sending and reflecting electrodes to extend impedance matching range. And a thin film phase shifter is monolithically fabricated on a substrate. As the result low insertion loss and no matching adjustment can be achieved at the same time, and that without any increase of chip size and electrical parts.
Effect of Li/Nb Ratio on the SAW Velocity of 128°Y–X LiNbO3 Wafers
Authors: Yamada Kazuhiro , Takemura Hirofumi , Inoue Yuuji , Omi Tadao , Matsumura Sadao
Published: March 2014

The effects of the composition on the SAW velocity and the electro-mechanical coupling constant (k
2) of 128°-rotated Y-cut X-propagating (128°Y–X) LiNbO3 wafers have been quantitatively investigated. The composition of the wafer was determined from the Curie temperature detected by DTA measurements and the SAW velocity from the measurements on a 70 MHz band SAW Comb filter. From the experiments, both the SAW velocity and the k
2 obviously depended on the composition of the wafer. Variations of the SAW velocity and the k
2 per 1 Li2O mol% were 43.4 m/sec and 0.43%. At the composition of 48.6 Li2O mol% which was reported as the congruent melt composition by Carruthers et al.,1) the SAW velocity and the k
2 were 3986 m/sec and 5.8%, respectively.
Energetic Oxygen Atoms in RF Sputtering of ZnO
Authors: Tominaga Kikuo , Yuasa Takayuki , Kuroda Kenji , Tada Osamu
Published: March 2014

Energetic particles bombarding the substrate placed in front of the target was observed by time-of-flight method for the film preparation of ZnO by RF planar magnetron sputtering and RF diode sputtering. It was confirmed that energetic oxygen atoms are bombarding the substrate. At the same time, fairly amount of energetic oxygen molecules were also observed. The total energies of the energetic oxygen atoms and molecules were extimated from the analysis of the time-of-flight spectra, and the estimated total energies for RF sputtering were compared with those for DC sputtering. It has been confirmed that the influence of the energetic oxygen atoms and molecules in Rf sputtering on ZnO films is the same order as that of DC sputtering.
Electrical Properties of Rapid Quenched Bi4Ti3O12 Amorphous Ribbons
Authors: Shoji Kazuo , Uehara Yasuo
Published: March 2014

The electrical properties before and after annealing for rapid quenched Bi4Ti3O12 amorphous ribbons have been studied. Before crystallization, its dielectric breakdown strength is very high, while its dielectric constant is rather low since it is non-ferroelectricity. After crystallization, its room temperature dielectric constant becomes higher than that for a sample prepared by ordinary firing method. For instance, the value for the sample annealed at 650°C is 300, which is about two times as large as that for the latter. Similar behaviors on the ferroelectric and breakdown properties of the annealed sample are also observed.
Progress in the Phenomenological Theory of Piezoelectricity in the Ferroelectric Materials
Authors: Marutake Masakazu
Published: March 2014

A history of piezoelectric materials is reviewed in retrospect since the discovery of Rochelle salt, and a phenomenological theory is reviewed of the ferroelectricity on which the piezoelectricity is based. A distinction between the isothermal and the adiabatic process, a pseudoproper ferroelectric transition and an elastic anomaly are described.
It is proposed that (1) the spontaneous polarization is not necesarily restricted to that of the soft mode and (2) the nonlinear terms determining the spontaneous values should be considered, not only for the quantity which is responsible for the ferroelectric transition but also for those that couple with the former in Mueller's theory.
TSC Study on Fe-Doped Barium-Strontium Titanate Ceramics
Authors: Fukami Tatsuo , Kusunoki Makoto , Tsucniya Hidetoshi
Published: March 2014

A Thermally Stimulated Current in paraelectric barium-strontium titanate ceramics doped with iron up to 1% was studied in the range above the room temperature. Two TSC peaks, A and B, was observed: The peak A lied around at 90°C, the activation energy being 0.68 eV, whereas the peak B was found around at 130°C with the activation energy of 0.97 eV and regarded as due to migration of oxygen vacancies. These results suggest that the asymmetric hysteresis property in iron-doped ferroelectric ceramics may be brought about from the same charges.
Electrical Properties and Microstructure of Ca Modified PbTiO3 Ceramics
Authors: Yamamoto Takashi , Saho Munenobu , Okazaki Kiyoshi , Goo Ed.
Published: March 2014

The (Pb1-x
, Ca
x
)TiO3, (x=0.12 to 0.5) ceramics were sintered, and the relationship between dielectric, piezoelectric properties and microstructure were classified as a function of Ca content. There existed no phase boundaries over the range of Ca content of 0.12 to 0.5 mol. However, the ratio of k
t and k
p was drastically changed as a function of Ca content. These changes were related with the appearance of 90° domains and superlattice.
Dielectric Characteristics of Several Complex Oxide Ceramics at Microwave Frequencies
Authors: Maeda Masaki , Yamamura Takashi , Ikeda Takuro
Published: March 2014

Dielectric characteristics of several complex-oxide compounds have been investigated. The materials investigated are those with rutile- or rutile-like crystal structure, and the complex-oxides related to TiO2. Some candidates for microwave resonator materials are shown.
Effect of Measurement Error of Cardiotocograph to Spectral Analysis
Authors: Noguchi Yasuaki , Hataoka Hiroshi , Sugimoto Suguru , Kobayashi Hisaaki , Kobayashi Mitsunao
Published: March 2014

It is reported that the measurement error of the fetal heart rate variability, which is obtained by a cardiotocograph with a Doppler ultrasonics signal, is large even if the auto-correlation technique is used. Simulations are performed to estimate the effect of the measurement error on the spectral analysis. The following two respects are confirmed: (1) when the error is distributed uniformly from -15 msec to +15 msec, the noise level of the spectrum is -12 dB, and (2) the noise level is not greatly different whether the distribution of the measurement error is uniform or Gaussian.
Analysis of SAW Single-Phase Unidirectional Transducer and Its Application to Reflectors and Resonators
Authors: Takeuchi Masao , Yamanouchi Kazuhiko
Published: March 2014

A coupled-mode theory is used to analyze a new type of single-phase unidirectional transducer utilizing the internal reflections of floating electrodes of electrically open and shorted strips (FEUDT). Frequency responses of radiation admittance, insertion loss and reflection coefficient are calculated from simple closed-form solutions of coupled-mode equations. Experimental results are given for test devices fabricated on a 128° YX LiNbO3 substrate, which yield good agreement with present theory. A potential application of FEUDT to reflectors and resonators is also described.
Precise Measurement of Surface Acoustic Wave Velocity Using a Swept Frequency IDT-NDE System
Authors: Nomura Tooru , Yasuda Tsutomu , Shiokawa Showko
Published: March 2014

A method of measuring the surface acoustic wave (SAW) velocity is presented. Three interdigital transducers (IDT's) deposited on a piezoelectric substrate are used to measure SAW velocity of sample materials using a fluid couplant. The output voltage of the IDT is measured as a function of the acoustic wave frequency. A unique curve is obtained by the interference between the two outputs of the close IDT's. The SAW velocity is obtained from the frequency dependence of the curve. Measurements are made for anisotropic materials at frequencies from 20 to 30 MHz. The experimental results obtained in this manner agreed with the theoretical ones.
A Study of Al-Alloy Electrodes for High Power SAW Filters
Authors: Hosaka Norio , Yuhara Akitsuna , Watanabe Hitoshi , Yamada Jun , Kajiyama Morio
Published: March 2014

Durability of aluminum-alloy electrodes for high power SAW filters which are used for antenna duplexers in cellular portable telephones is experimentally investigated. Titanium added aluminum is deposited by DC magnetron sputtering. The new alloy expands the limitation on the driving power of the filters. Temperature, particularly, accelerates the degradation of the high power filters, the film resistance causes an even greater increase in temperature. Thus, optimum value for titanium of 0.4 wt.% can be achieved for high durability filters.
A Model Experiment of Wave Propergation in Acoustic Microscope
Authors: Negishi Katsuo , Li Hyo Ung
Published: March 2014

Using stroboscopic photoelastic method together with schlieren technique, simultaneous visualization of ultrasonic waves in water and glass has been made as a model experiment of wave phenomenon occurring in a scanning acoustic microscope. Evidence of reradiation into water from leaky surface acoustic waves excited by the incident converging ultrasonic pulses of 5.5 and 1.2 MHz is shown.
Acoustic Holography Using Omnidirectional Copolymer Array Transducer
Authors: Koyama Kiyohito , Yamamoto Tadashi , Tamura Yasutaka , Wada Yasuku
Published: March 2014

A new array transducer made of Vinylidene Fluoride-Trifluoroethylene Copolymer was developed for a holographic imaging system. The new array transducer consists of cylindrical elements which have a low electrical impedance and a wide directivity. The array transducer is constructed of 17 elements, 16 of which act as transmitting transducers. An element located at the center of the array acts as a receiving transducer. The holographic image of the target is reconstructed by the square detection using a personal computer.
Calculation of Ultrasonic Attenuation by means of Nonlinear Lattice Model
Authors: Suzuki Tetsuro
Published: March 2014

An attempt has been made to calculate the anomalous ultrasonic attenuation associated with the martensitic transformation from the nonlinear lattice model by use of the fluctuation dissipation formula. Although the qualitative features of the anomalous temperature dependence of the ultrasonic attenuation is reproduced, a reinterpretation of the nonlinear lattce model, i.e. the replacement of an atom by a group of atoms, is found to be required, in order to obtain quantitatively valid results for the ultrasonic attenuation.
Gap State Profiles in Amorphous Selenium Studied by Photoacoustic and Photoconductivity-Quenching Spectroscopy
Authors: Kanemitsu Yoshihiko , Hayano Tomio , Koseki Kazuhiro , Imamura Shunji
Published: March 2014

Gap state profiles in amorphous selenium were studied by photoacoustic spectroscopy. A peak of photoacoustic spectra is located at 1.43 eV. The height of this peak decreases for the samples deposited at high substrate temperatures and for arsenic-doped samples. The near-infrared optical quenching spectra of photoconduction also exhibit a peak at the same energy of 1.43 eV. The experimental results suggest that the level of positively charged defect state D
+ is located at 1.43 eV above the valence band.
Photoacoustic and Photoluminescent Studies on Fe2O3 Semiconductor Electrode
Authors: Takaue Ryoichi , Matsunaga Morio , Hirano Shigeru , Hosokawa Kunisuke
Published: March 2014

The non-radiative and radiative processes of electrons have been investigated by photoacoustics and photoluminescence to elucidate the photoelectrochemical response of ferric oxide electrodes in 0.1 N NaOH electrolyte.
Characteristic Changes of Amorphous Thin Film by Microwave Ultrasonics
Authors: Tokunaga Yoshiaki , Tamuki Jun , Kita Yuji
Published: March 2014

The purpose of this paper is to describe the changes in characteristics of amorphous chalcogenide thin film, As2S3, by microwave ultrasonics. The film was about 3 µ thick and was evaporated on sapphire substrate. It was found that transparency of visible light passing through the film was shifted to longer wavelengths near the absorption edge in the range from 500 nm to 600 nm by application of the ultrasonic flux. This freature seems similar to the photo-darkening which occurs from the irradiation with photon energy such as that used in a laser.
Study on Structural Relaxation of Highly Viscous Liquids by Brillouin Scattering Method
Authors: Hashitani Ryuki , Koda Shinobu , Nomura Hiroyasu
Published: March 2014

The velocities of highly viscous liquids in the gigahertz region were measured in the wide temperature range (about 200–330 K) by Brillouin scattering method. In most cases, the velocity dispersions due to structural relaxation were observed around room temperature. The relaxation spectra for storage modulus could be reproduced by a single relaxation equation. However, they deviated from the relaxation spectrum predicted by the reduced variable method proposed by Lamb et al. toward the high frequency side.
Ultrasonic Measurement of Melittin-Liposome System
Authors: Mitaku Shigeki , Sakka Toshiaki , Hotta Tohgo
Published: March 2014

The lysis of dimyristoyl phosphatidylcholine liposomes by melittin, a bee venom of 26 amino acid residues, was studied by ultrasonic as well as optical measurements. The time course of the lysis indicates that the ultrasonic relaxation reflects the continuous lysis of lipid bilayers, whereas the sharp decrease of the optical absorbance at 350 nm is correlated with the end of the reaction.
Estimation of Waves Diffracted by a Cylinder –Analysis by Diffraction Theory for Solid Obstacles–
Authors: Sato Mitsunobu , Saito Hikaru , Tabei Makoto , Ueda Mitsuhiro
Published: March 2014

Recently we have developed a diffraction theory for solid obstacles. The waves diffracted by a cylinder are estimated by this theory and the results are compared with those obtained by the rigorous relation and the conventional approximation. Comparison shows that our theory is effective if the radius of the cylinder is smaller than the wavelength of sound waves.
An Analysis of Excitation Characteristics of Interdigital Transducers for Surface Acoustic Waves
Authors: Koshiba Masanori , Hasegawa Koji , Inagawa Kiyoshi
Published: March 2014

An equivalent network theory and a coupled mode theory are described for the analysis of excitation characteristics of interdigital transducers (IDT) for surface acoustic waves. Circuit parameters of equivalent circuits and coupling and transduction coefficients of coupled mode equations can be theoretically determined by applying the finite-element method to an infinite array corresponding to an electrically shorted or open IDT. Examples are computed for two types of IDTs fabricated on a 128° Y-X LiNbO3 substrate. One is a uniform type of IDT and the other is a single-phase unidirectional transducer utilizing internal floating electrodes.
Surface Acoustic Wave Transducers with Narrow Gap Interdigital Electrodes and Low Loss Filters
Authors: Yamanouchi K. , Meguro T. , Chen Z. H. , Matsumoto K.
Published: March 2014

A new surface acoustic wave interdigital transducer (IDT) and unidirectional transducer (UDT) are described. Using a lift off-etching method or a lift off-anodic oxidation method, controllable gaps between electrodes with good insulation can be obtained. Experimental results show 7.8 dB insertion loss with small ripples of ±1.2 dB for a conventional IDT, and directivities of 6 dB/transducer at 438 MHz for a floating electrode type unidirectional transducer (FEUDT) and 17 dB/transducer for its second harmonic at 868.5 MHz. Also, minimum insertion loss of 3.6 dB for a low loss FEUDT filter at 440 MHz is obtained. These techniques are applied for the separation between electrodes of VLSI.
The Second-Order Temperature Coefficient of Surface Wave Propagating on Quartz Substrate with Arbitrary Cuts
Authors: Uehara Michihiro , Shimizu Yasutaka
Published: March 2014

The second-order temperature coefficient of Rayleigh wave and leaky surface wave propagating on quartz substrate was theoretically calculated for all cuts and propagation directions by changing Euler's angle. The temperature characteristics were appraised by temperature coefficient of delay (TCD) and the second-order temperature coefficient. Many cuts more stable than the ST-cut were obtained for Rayleigh wave. For leaky surface wave, new cuts with both zero TCD and zero second-order coefficient, which were more stable than the LST-cut, were theoretically obtained.
Multilayered Magneto-Surface-Acoustic-Wave Devices Composed of Highly Magnetostrictive Amorphous Fe–B Films and Thin Insulating Interlayers
Authors: Inoue Mitsuteru , Tsuboi Yoshihiro , Yokokawa Narutoshi , Fujii Toshitaka
Published: March 2014

Magneto-surface-acoustic-wave (MSAW) devices with three-layer structure were constructed by RF-sputtering, where a thin insulating SiO2 interlayer was sandwiched between two magnetostrictive amorphous Fe–B films of equal thickness. This was based on our previous study which predicted that such multilayered devices are useful to improve MSAW properties since they reduce eddy-current losses in alloy films. More than a 12 dB/cm loss reduction was achieved at the operating frequency of 52 MHz in comparision with single layer devices of the same thickness. The total thickness of magnetic films was found to be a significant parameter in determining the MSAW properties in multilayered devices.
An Ultrasonic Motor Using Non-Axisymmetric Vibration Modes of a Piezo-Ceramic Annular Plate
Authors: Tomikawa Yoshiro , Takanon Takehiro , Hirata Hiroshi , Ogasawara Toshiharu
Published: March 2014

This paper deals with an ultrasonic motor which uses non-axisymmetric vibration modes of a piezo-ceramic annular plate. Some forms of construction of the motor are proposed, and analysis of the annular plate, which is necessary for realization of a good ultrasonic motor, is made. Measured characteristics of a trial motor are also presented. The ultrasonic motor dealt with herein shows fairly good characteristics as a thin type form.
Edge Effect on Attenuation Constants of a Steel Plate Floating in Water
Authors: Endoh Nobuyuki , Kawakami Yoshiroh , Higashiyashiki Minoru , Fujimoto Syohji
Published: March 2014

In order to estimate accurately a ship's radiation noise in the sea, we earlier reported on the attenuation constants of a small steel plate. In this paper, the radiation influence from the edge of the plate is described. Experiments were carried out using the reverberation method. The edge effect on attenuation constants was measured by decay times as a function of the ratio R (edge length/surface area of plate). Attenuation constants increased with frequency over the coincidence frequency and with the ratio R. The experimental results show that a small steel plate requires a certain correction in the attenuation constant measurement.
Simultaneous Sensing of Acoustic Wave and Temperature Using a Polarization-Maintaining Fiber
Authors: Takahashi Sumio , Murakami Yasunori , Kikuchi Toshiaki , Yagi Ryohei , Hasegawa Akio
Published: March 2014

Simultaneous sensing of acoustic wave and temperature change using a polarization-maintaining fiber is experimentally investigated. Temperature change is detected by homodyne interference of the X and Y eigenmodes of the fiber, while acoustic wave is detected by heterodyne interference of the X component of the output light from the fiber and the reference beam. Simultaneous sensing was successfully demonstrated.
Use of a Wedge Transducer Array for Linear Scanning of an Angled Shear Ultrasonic Beam
Authors: Kubota Jim , Fujita Akinari , Sonoda Shinji
Published: March 2014

An angled 5 MHz shear wave electronic linear scanning technique was developed for high speed ultrasonic testing of spherical gas storage tanks. An array of wedge transducer elements six wavelengths wide was arranged normal to the weld line of the tank with a 4 mm pitch. The wedge was made so as to form a 70 degree angled shear wave ultrasonic beam, inclined 45 degrees to the weld line. Sensitivity (S/N), and the sound field were investigated by a trial system and verified as able to detect cracks 3 mm long and 1 mm deep.
Photoinduced Effects on Gap State Profiles and Recombination Processes in Amorphous Selenium Studied by Photoacoustic Spectroscopy and Xerographic Discharge Measurements
Authors: Kanemitsu Yoshihiko , Koseki Kazuhiro , Imamura Shunji
Published: March 2014

The effects of prolonged illumination on gap state profiles and recombination processes in amorphous selenium were studied by photoacoustic spectroscopy and xerographic discharge measurements. The photoacoustic signal decreases and the density of charged defect states increases with increasing illumination time. The experimental results show that after prolonged illumination the trapping at charged defects increases and recombination of holes with electrons at neutral defects decreases. We propose a model of photostructural change and recombination processes in amorphous selenium.
Present State of the Art of Ultrasonic Motors
Authors: Ueha Sadayuki
Published: March 2014

To describe the field of ultrasonic motors, the various motors developed to date must be classified. Since the form of ultrasonic motor seems to depend on the way of creating the elliptic motion of the contacting surface of the motor, most motors are classified from this point of view. The principle, features and problems of the ultrasonic motor are also briefly described.
Acoustic Properties of High Tc Superconductor YBa2Cu3O7-x
Authors: Tingzhang Deng , Liangkun Zhang , Huicheng Gu , Zhili Xiao , Liquan Chen
Published: March 2014

Ultrasonic attenuation and velocity measurements down to 4.2 K were performed on high T
c superconductor Y–BaCu–O samples of different sintering procedures. Attenuation peaks appeared at different temperatures, probably being related to the sintering procedure. However, one peak in attenuation obeserved in both samples below T
c may be due to the glass behavior of the samples. The mean sound velocity, which is related to the Debye temperature and specific heat, has been calculated using the experimental data of longitudinal and transverse sound velocity. The slope of mean velocity vs temperature is changed near T
c.
Hole Burning in Piezoelectric Powders
Authors: Tsuruoka Fujio
Published: March 2014

Hole burning was introduced with large amplitude pulsed oscillating strain in the spectrum of electric field energy absorption using piezoelectric powders. The damping coefficient of particle oscillation in the frequency range coincident with the Fourier component of applied pulse became smaller. The stirring treatment that changed the angle between the piezoactive axis of a particle and the electric field direction did not completely eliminate the hole. Experimental results were qualitatively explained by dislocations caused by large amplitude strain.
A Low-Impedance Ultrasonic Probe Using a Multilayer Piezoelectric Ceramic
Authors: Saitoh Shiroh , Izumi Mamoru , Abe Kazuhide
Published: March 2014

An ultrasonic probe employing a multilayer ceramic is proposed for improving the S/N ratio. The S/N ratio is degraded when the probe impedance rises in relation to parallel combined impedances of cable and receiver circuits. The impedance of n layers of ceramic can be reduced to 1/n
2 of a single ceramic layer, thus permitting the S/N ratio to be raised. A co-firing multilayer method is introduced to achieve a multilayer ceramic with large adhesive strength. As a result, the S/N ratio has been improved as much as 8 dB over that of conventional probes under the same drive voltage.
Hydrostatic Pressure Properties of Piezoelectric Flexible Composites
Authors: Ogura Kohji , Ohya Kanji , Banno Hisao
Published: March 2014

Hydrostatic pressure properties of piezoelectric flexible composites are reported as a function of PbTiO3 volume fraction and particle size. These composites, typically referred to as Piezo-Rubber, consist of PbTiO3 and a polymer and were developed at NTK-NGK.
There is a hydrostatic pressure independence region and a hydrostatic pressure dependence region in terms of PbTiO3 volume fraction and its average particle size. The hydrostatic pressure dependence region can be further separated into a linear correlational region and a non-correlational one.
Ceramic Devices for Frequency Control and Selection
Authors: Fujishima Satoru
Published: March 2014

Application of ceramic devices for frequency control and selection is spreading over a wide frequency range. This report introduced many kinds of ceramic materials for frequency control and selection. An oscillator circuit with a piezoelectric ceramic resonator was analyzed and reliability of each package for resonators and filters was reported comparing reliability tests to field data.
Dispersion of Elastic Waves in a Transverse Isotropic Circular Cylinder
Authors: Wang Ning , Ueha Sadayuki
Published: March 2014

An analytical treatment for propagation of elastic waves in a transverse isotropic elastic cylinder is described. The dispersion curves for the phase velocities are computed by varying the parameter of the anisotropy. It is found that two modes with different phase velocities propagate without dispersion in an extreme transverse isotropic circular cylinder.
Transient Analysis of a Piezoelectric Ceramic Thin Plate by Spatial Network Method
Authors: Sato Masahiro , Yosnida Norinobu , Fukai Ichiro
Published: March 2014

The application of a spatial network method to a piezoelectric ceramic thin plate is described. The concept of this method is both the representation of the plate by the electrical lattice network and the formulation in time domain by Bergeron's method. The method has the merit of being applicable to treat any medium conditions by electrical analogy and to analyze numerically an arbitrary shape of the plate in time domain.
Excitation of the Edge Mode Utilizing Piezoelectric Shear Effect
Authors: Watanabe Hiroshi , Shimizu Hiroshi
Published: March 2014

The electrical excitation of the edge mode in a thin piezoelectric ceramic strip is studied on the basis of its strain distribution, and a new excitation method utilizing the piezoelectric shear effect is proposed. Applying this method, miniaturized piezoelectric resonators with high electrical impedance and low capacitance ratio are developed for use in the medium frequency range below several megahertz.
Electrostrictive Materials for Ultrasonic Probes in the Pb(Mg1/3Nb2/3)O3–PbTiO3 System
Authors: Masuzawa Hiroshi , Ito Yukio , Nakaya Chitose , Takeuchi Hiroshi , Jyomura Shigeru
Published: March 2014

Electrostrictive ceramics in the Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) solid solution system are investigated as the transducer material for ultrasonic probes whose electro-acoustic conversion efficiency is controlled by an applied DC bias voltage. Considering the electromechanical coupling factors induced under practical DC bias voltage and the normal using temperature, it is concluded that the most promising composition is 0.09 mole fraction of PbTiO3. A basic pulse-echo measurement confirmed that electro-acoustic conversion efficiency of an ultrasonic probe made of electrostrictive ceramics is controlled by an applied DC bias field.
Crystal Growth and Nonlinear-Optical Properties of Ni and Fe Boracites
Authors: Uesu Yoshiaki , Murase Yusuke , Isnigaki Takeo
Published: March 2014

Single crystals of Ni–Cl, Ni–Br, Ni–I and Fe–I boracites were grown by chemical vapor-transport method. By using a horizontal-type vessel in place of vertical-type one developed by Schmid, the sophisticated process could be simplified. Crystals with maximum edge-length of 6 mm were obtained. Optical second harmonic-generation was measured as a function of temperature on a single crystal of Fe–I boracite, while on powdered crystals of Ni–Br boracite. Second harmonic intensities were found to decreases toward the ferroelectric transition temperature. In temperature range from 293 K to 400 K, there is no indication that the second harmonics from Fe–I boracite satisfies the phase-match condition.
A Piezoelectric Slider Composed of Bimorph Vibrators
Authors: Fukami Tatsuo , Shimoe Kazunobu , Kawaguchi Yoshitaka
Published: March 2014

A new type of linear motor has been proposed by using dual piezoelectric bimorph vibrators whose free ends are coupled to each other with an elastic metal arc. The selection of the driving bimorph makes it possible to determine the moving direction with a velocity, typically, of 30 cm/s. A newly devised piezoelectric slider composed of two sets of the linear motors has been shown having features such as easy controllability by computer and worthy arbitrability of its moving mode.
Temperature Stability of a PBZMT Electrostrictive Ceramic
Authors: Abe Kazuhide
Published: March 2014

Electrostriction was precisely measured at temperatures ranging from 0°C to 40°C for a newly developed (Pb, Ba) [Zn1/3Nb2/3), (Mg1/3Nb2/3), Ti]O3 ceramic material in multilayer configuration. The temperature coefficient of electrostriction was evaluated to estimate the temperature stability of electrostriction. The temperature coefficient of the material was found to be about 1%°C-1. The coefficient also had an applied voltage dependence, in which the coefficient decreased with increasing field strength. The value and manner of the voltage dependence were discussed, considering the temperature dependence of dielectric stiffness coefficients, including higher order nonlinear terms.