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Distributed acoustic sensing (DAS) using existing optical fiber cables facilitates high‐density seismic observation. However, few studies have examined the reliability of the seismic waveform amplitude recorded by DAS. In this study, a DAS network was connected to optical fiber cables installed over a distance of 75 km along a high‐speed train (Shinkansen) railway in the Kumamoto prefecture, Japan. We successfully observed strong motions of the Mj6.6 earthquake (approximately 150 km from the fiber) on 22 January 2022, in Hyuga‐nada, in addition to several small local earthquakes. The observed strong motions from the Mj6.6 earthquake, using DAS, exhibited cycle skipping (clipping) issues due to dynamic range limitations at numerous channels. To address this, we estimated the shaking map, representing maximum strain distributions for Mj6.6, by replacing the clipped data with information from nearby unclipped channels and scaling their RMS amplitudes based on S‐coda (unclipped). Furthermore, we verified the reliability of the amplitude information obtained from DAS by estimating the distance attenuation of seismic waves while correcting for the differences in the structure type and coupling as much as possible. The distance attenuation property of local earthquakes was consistent with that of the peak ground velocities obtained from seismometers, indicating that DAS data acquired using fibers installed on infrastructure (various structures) can also be utilized to assess the spatial distribution of the relative amplitude values along the fiber. Obtaining high‐density seismic motion distributions is important for earthquake early warning and accurate damage estimation of strong motions. In the past decade, the use of distributed acoustic sensing (DAS) for seismological purposes has grown rapidly. By utilizing existing dark fibers, such as telecommunication cables, high‐density seismic observation networks can be established in residential areas. In this study, DAS was applied to an existing optical fiber cable installed along a railway line, which recorded strong ground motions of Mj6.6 originating from a subduction zone, as well as numerous regional earthquakes. Although the technique uses optical phase differences for strain measurements and therefore has a poor response to strong ground motions, we resolve this issue using the correct data from neighboring stations as a reference and estimated the shaking distribution every 5 m along 75 km of the railway line. Additionally, when we analyzed the distance attenuation of small regional earthquakes, we found that the attenuation characteristics were similar to those obtained from permanent seismometers. These findings will significantly impact society in the future, particularly as the fiber cables replace conventional seismic observation networks. As a result, ultra‐high‐density observation networks will be capable of issuing more accurate earthquake early warnings and estimating damage following earthquakes. We successfully observed strong motion from the Mj6.6 earthquake in Hyuga‐nada using Distributed acoustic sensing (DAS) over 75 km along railwayThe shaking map of the Mj6.6 was estimated by replacing the clipped channels with nearby unclipped channels and scaling their RMS amplitudes of S‐codaDistance attenuation property of local earthquakes of DAS consistent with that of peak ground velocities from continuous seismometers We successfully observed strong motion from the Mj6.6 earthquake in Hyuga‐nada using Distributed acoustic sensing (DAS) over 75 km along railway The shaking map of the Mj6.6 was estimated by replacing the clipped channels with nearby unclipped channels and scaling their RMS amplitudes of S‐coda Distance attenuation property of local earthquakes of DAS consistent with that of peak ground velocities from continuous seismometers

We report a measurement of the shape of the source star in microlensing event MOA 2002-BLG-33. The lens for this event was a close binary whose centre-of-mass passed almost directly in front of the source star. At this time, the source star was closely bounded on all sides by a caustic of the lens. This allowed the oblateness of the source star to be constrained. We found that $a/b = 1.02^{+0.04}_{-0.02}$where aand bare its semi-major and semi-minor axes respectively. The angular resolution of this measurement is approximately 0.04 $\mu\rm{arcsec}$. We also report HST images of the event that confirm a previous identification of the source star as an F8-G2 turn-off main-sequence star.

We report a measurement of limb darkening of a solar-like star in the very high magnification microlensing event MOA 2002–BLG–33. A 15 hour deviation from the light curve profile expected for a single lens was monitored intensively in Vand Ipassbands by five telescopes spanning the globe. Our modelling of the light curve showed the lens to be a close binary system whose centre-of-mass passed almost directly in front of the source star. The source star was identified as an F8–G2 main sequence turn-off star. The measured stellar profiles agree with current stellar atmosphere theory to within ~4% in two passbands. The effective angular resolution of the measurements is <1 μas. These are the first limb darkening measurements obtained by microlensing for a Solar-like star.

We detected four outbursts of V359 Cen (possible nova discovered in 1939) between 1999 and 2002. Time-resolved CCD photometry during two outbursts (1999 and 2002) revealed that V359 Cen is actually a long-period SU UMa-type dwarf nova with a mean superhump period of 0.08092(1) d. We identified its supercycle length as 307–397 d. This secure identification of the superhump period precludes the previously supposed possibility that V359 Cen could be related to a WZ Sge-type system with a long persistence of late superhumps. The outburst characteristics of V359 Cen are, however, rather unusual in its low occurrence of normal outbursts.

Prominent excursions in the number of cosmogenic nuclides (e.g., 10Be) around 774 CE/775 document the most severe solar proton event (SPE) throughout the Holocene. Its manifestation in ice cores is valuable for geochronology, but also for solar‐terrestrial physics and climate modeling. Using the ECHAM/MESSy Atmospheric Chemistry (EMAC) climate model in combination with the Warning System for Aviation Exposure to SEP (WASAVIES), we investigate the transport, mixing, and deposition of the cosmogenic nuclide 10Be produced by the 774 CE/775 SPE. By comparing the model results to the reconstructed 10Be time series from four ice core records, we study the atmospheric pathways of 10Be from its stratospheric source to its sink at Earth's surface. The reconstructed post‐SPE evolution of the 10Be surface fluxes at the ice core sites is well captured by the model. The downward transport of the 10Be atoms is controlled by the Brewer‐Dobson circulation in the stratosphere and cross‐tropopause transport via tropopause folds or large‐scale sinking. Clear hemispheric differences in the transport and deposition processes are identified. In both polar regions the 10Be surface fluxes peak in summertime, with a larger influence of wet deposition on the seasonal 10Be surface flux in Greenland than in Antarctica. Differences in the peak 10Be surface flux following the 774 CE/775 SPE at the drilling sites are explained by specific meteorological conditions depending on the geographic locations of the sites. During large solar storms, high energy particles are hurled with enormous force toward Earth by the Sun. As these particles collide with atmospheric constituents (such as oxygen or nitrogen) unique nuclides of cosmogenic origin are formed in the higher atmosphere. From there they are transported downwards and finally precipitate at the surface due to different sink processes. Their imprints can be conserved over thousands of years within natural archives, such as ice cores or tree rings. Analysis of these natural archives around the globe indicates that the strongest solar storm over the last 10.000 years happened around 774 CE/775. This event is estimated to have been up to two orders of magnitude stronger, than the strongest known events documented for the satellite era. In this study, we model and analyze the transport and deposition of the cosmogenic nuclides produced by the extreme 774 CE/775 event, by applying a new experimental setup. Our results might help to interpret the fingerprints of historical extreme events with respect to the prevailing atmospheric conditions. The modeled transport and deposition of the cosmogenic nuclide10Be produced by the 774/775 solar proton event was compared to 10Be ice core recordsHemispheric differences in stratospheric and cross‐tropopause transport, and deposition were identified, with polar summertime maxima of 10Be surface fluxDifferences in reconstructed10Be surface fluxes are explained by the local ratio of wet to dry deposition maximizing inthesummertime The modeled transport and deposition of the cosmogenic nuclide10Be produced by the 774/775 solar proton event was compared to 10Be ice core records Hemispheric differences in stratospheric and cross‐tropopause transport, and deposition were identified, with polar summertime maxima of 10Be surface flux Differences in reconstructed10Be surface fluxes are explained by the local ratio of wet to dry deposition maximizing inthesummertime

As a result of the 2011 off the Pacific Coast of Tohoku Earthquake, five slope failures occurred in a residential area on artificial valley fills in Taiyo New Town, Yamamoto, Miyagi Prefecture. The site was constructed by leveling a hilly area and using the cut materials as fill for the valleys to provide foundation ground for houses. The fill material was sandy and was derived from the weathering of tuffaceous sandstone which had formed the natural ground. Each of the five slope failures was observed to have occurred either at the edge of the artificial valley fills or within the embankment sections that had been widened for road construction. Laboratory tests show that the fill, which had a fines content of Fc=20%, had a very low liquefaction resistance, which further decreased with the application of initial shear stress. A pseudo-static slope stability analysis, using conventional strength parameters, could not explain the slope failure at one of the sites that failed, but it could explain the slope failure when the dynamic strength was used to represent the soil strength at the slip surface. Thus, the slope failures in Taiyo New Town, at least at the one site analyzed in this study, could be attributed to the liquefaction of the fill material induced by the intense shaking.

Modulation of the Purcell effect by controlling both the Q-factor and detuning in a quantum-dot-nanocavity coupled system was investigated. The Q-factor and detunings are controlled independently by using a nanocavity, a waveguide and a reflector formed in a two-dimensional photonic crystal slab, in combination with a newly developed nitrogen adsorption/desorption technique that enables local control of the refractive index. We investigated analytically and experimentally how the density of states of cavity mode is modulated, and we experimentally clarified how the emission of a quantum dot on resonance with a cavity is modulated. We observed that the emission of a quantum dot via a cavity mode was increased by 3.3 times when the Q-factor was changed from 3,500 to 6,900 while keeping the detuning fixed. The dependence of the Purcell effect on the Q-factor was directly observed.

We present a two-dimensional combinatorial investigation of resonant Raman and fluorescence enhancement in silver and gold sandwich structures. Gold and silver, separated by a thin alumina spacer layer, were deposited in two orthogonal gradients, with a thickness from a few hundred to a few nanometers, covering the range from island films through percolation to continuous films. Resonant Raman spectra of Rhodamine 6G adsorbed on the substrate surface were recorded in a 13 × 13 matrix using an automated scanning stage. The most Raman-active substrates were composed of silver (8 nm)-on-alumina (7 nm)-on-gold (5 nm). They consist of both gold and silver discontinuous nanoparticle films separated by alumina, forming a labyrinthine network structure. Gold-on-alumina-on-silver substrates also displayed increased activity compared with that of gold-on-alumina substrates. Maximum fluorescence intensity was observed on silver films nominally 35 nm thick covered by 8 nm of alumina. The efficacy of the combinatorial method to correlate multiple aspects of the measurements and reduce uncertainties is demonstrated.

Utilizing a combinatorial method, we used spectroscopic ellipsometry to determine the dielectric functions of silver island films over a large range of sizes and morphologies from the percolation threshold down to average particle size smaller than 5 nm. We measured films on silicon substrates with 2 and 20 nm oxide layers and compared the surface-enhanced Raman scattering properties of the films. As expected, the films on 20-nm-thick oxide substrates showed increased Raman counts due to reduced damping of the plasmon resonance; however, the optical absorption was greater in the films on 2 nm oxide. The maximum Raman scattering was observed for average particle diameters of 13.6 and 25 nm and interparticle spacings of 3.3 and 4.1 nm for the 2 and 20 nm oxide substrates, respectively. The use of a combinatorial method resulted in significantly reduced uncertainties by avoiding multiple sample preparations and allowed unambiguous identification of optimal film parameters for the different substrates.

Cauliflower‐like protrusions formed in CVD processes under diffusion‐limited conditions have been studied both experimentally and theoretically. Both approaches indicate that the difference in diffusion fluxes to the film and to the protrusions controls the growth of such protrusions. However, direct comparisons of these two approaches have never been done, probably due to the complexity of the theoretical models. To simplify model protrusion growth, we developed a one‐dimensional (1D) analytical model by hypothesizing the diffusion of growth species in the boundary layer above a growing film. Based on this model, we propose a non‐dimensional quantity, ksf/D, as an index of protrusion growth (Dis the diffusion coefficient of the growth species, ksis the surface reaction‐rate coefficient, and fis film thickness). This index represents more directly the protrusion growth than does the previously proposed index, the Damköhler number, Da= ksδ/D, where δ is boundary layer thickness. To obtain smooth, protrusion‐free films, D/ksshould be kept larger than the desired film thickness. By controlling the process conditions to satisfy this index, we successfully fabricated protrusion‐free films with SiC deposition from dichlorodimethylsilane (DDS).

Mechanisms controlling the deposition incubation time of Si on SiO2are studied. Two major mechanisms are considered to affect the incubation time: desorption of adsorbate that is not captured by existing islands, and differing sticking probabilities between islands and substrate. Results indicate that desorption of adsorbate seems to have less contribution and the sticking probability mechanism controls island growth (Figure), and therefore is the main cause for the incubation time in silane CVD processes.

We investigated the mechanism that determines the preferred orientation of polycrystalline silicon carbide (SiC) films prepared by CVD from a mixture of dichlorodimethylsilane (DDS) and He. X-ray diffraction (XRD) measurements indicated that the major growth direction is either the (220) or the (111) plane. We developed a numerical model for predicting the preferred orientation, assuming Langmuir-type adsorption and reaction of the growth species. This model suggests that the (111) plane appears under reaction-limited deposition, while the (220) plane appears under adsorption-limited deposition. Our experimental and numerical results show good qualitative agreement with experimental results for films prepared from methyltrichlorosilane (MTS) and H2.

The deposition of trumpet‐like protrusions during CVD of SiCis reported. The protrusions are deposited at the flow stagnation point of an impinging flow reactor. SEM analysis of the structures (Figure) indicates that they consist of aggregates of 1 μm sized particles surrounded by a smooth and dense film, which suggests a possible growth mechanism that produces preferential thermophoretic deposition on the protrusions rather than on the surface of the films.

There is growing evidence for a role of apoptosis in Alzheimer’s disease (AD). Recent findings suggest an increased susceptibility of lymphocytes to apoptosis in AD. To prove the hypothesis of systemic alterations in the apoptotic balance in AD, serum and cerebrospinal fluid levels of soluble CD95, which is known to mediate apoptosis, were measured. In the serum, AD patients exhibited significantly higher levels of CD95 than the controls (p = 0.017), suggesting an involvement of peripheral markers in AD.

Pb-Ti-Nb-O ferroelectric thin films with various Nb additions are grown on a Pt/Ti/SiO2/Si substrate at 400 °C by metal–organic (MO) CVD. A high density of dome-like surface protrusions is observed by scanning electron microscopy (SEM) in all the as-prepared films. Both the shape and the size of the surface defects are found to be Nb-content-dependent. The internal microstructure of the protrusions is further characterized by cross-section transmission electron microscopy (XTEM). The origins of these surface defects are discussed, based on the substrate hillock as well as the crystallization behavior of the film forming precursors during MOCVD. The development of the observed surface defects is modeled using a two-dimensional vector analysis.

The growth behavior of Pt crystallites vacuum-deposited on flat γ- and α-Al2O3 substrates was investigated by atomic force microscopy (AFM). In this study, we fabricated a thin layer of γ-Al2O3 on a planar sapphire (single crystalline α-Al2O3) substrate by Al⁺- and O⁺- ion implantation and annealing at 900 °C. AFM observation revealed that γ- and α-Al2O3 substrates have a negligible roughness compared with the size of the supported Pt crystallites deposited on them. The crystal structure was identified as a γ(111) plane for the γ-Al2O3 substrate, but an α(0001) plane for the sapphire substrate by Rutherford backscattering spectroscopy-channeling analysis (RBS-C) and X-ray diffraction analysis (XRD). We then observed the surface morphology of Pt crystallites on γ- and α-Al2O3 substrates, which were fabricated by sputtering of a Pt target. The as-deposited Pt thin film changed into Pt crystallites dispersed on the substrate with heat treatment at 800 °C in an oxidative atmosphere. It was found that the growth of Pt crystallites on γ-Al2O3 was less, although the particle growth of Pt on α-Al2O3 was remarkable. The growth process of the Pt crystallites was also discussed along with the surface structure of the Al2O3 substrates. We attribute the inhibition of Pt crystallite growth on the γ-Al2O3 substrate to the defective structure of the γ-Al2O3 compared with the stable structure of α-Al2O3.

Ultrafast modulation of interband-resonant light by intersubband-resonant light in n-doped GaAs/AlGaAs and GaN/AlGaN quantum wells was investigated by femtosecond pump-probe technique. A planar-type AlGaAs/GaAs modulation device shows a modulation speed of ∼1 ps at room temperature. The observed modulation efficiency indicates that 99% modulation can be achieved with a control pulse energy of ∼1 pJ when a waveguide-type device structure is utilized. The feasibility of the all-optical modulation in GaN/AlGaN quantum wells is also investigated. The intersubband carrier relaxation time, which mainly determines the modulation speed, is measured and is found to be extremely fast (130–170 fs). The results indicate that the optical modulation at a bit rate of over 1 Tb/s will be possible by utilizing the intersubband transition in GaN/AlGaN quantum wells. The modulation efficiency in GaN/AlGaN quantum wells is also discussed in comparison with that in GaAs/AlGaAs quantum wells.

We present observations of the microlensing event MACHO 98-BLG-35, which reached a peak magnification factor of almost 80. These observations by the Microlensing Planet Search (MPS) and MOA collaborations place strong constraints on the possible planetary system of the lens star and show intriguing evidence for a low-mass planet with a mass fraction 4 × 10-5? ? 2 × 10-4. A giant planet with = 10-3is excluded from 95% of the region between 0.4 and 2.5 REfrom the lens star, where REis the Einstein ring radius of the lens. This exclusion region is more extensive than the generic "lensing zone," which is 0.6-1.6 RE. For smaller mass planets, we can exclude 57% of the "lensing zone" for = 10-4and 14% of the lensing zone for = 10-5. The mass fraction = 10-5corresponds to an Earth-mass planet for a lensing star of mass ~0.3 M?. A number of similar events will provide statistically significant constraints on the prevalence of Earth-mass planets. In order to put our limits in more familiar terms, we have compared our results to those expected for a solar system clone, averaging over possible lens system distances and orientations. We find that such a system is ruled out at the 90% confidence level. A copy of the solar system with Jupiter replaced by a second Saturn-mass planet can be ruled out at 70% confidence. Our low-mass planetary signal (few Earth masses to Neptune mass) is significant at the 4.5 ? confidence level. If this planetary interpretation is correct, the MACHO 98-BLG-35 lens system constitutes the first detection of a low-mass planet orbiting an ordinary star without gas giant planets.

Recent studies point to glycolipid-enriched membrane (GEM) microdomains as the critical sites for TCR-mediated signal transduction. However, whether the TCR complex is localized in the GEM domain is not well-defined. In the present study, we analyzed localization of the TCR-CD3 complex in the GEM domain by isolating the GEM fraction with sucrose density gradient centrifugation. Although 10% of TCRζ chains was localized in the GEM fraction, most of the TCR complexes were excluded from the GEM before and after T cell activation, and the amount of TCRζ in the GEM was not increased after activation. However, the tyrosine-phosphorylated form of TCRζ was strongly concentrated in the GEM fraction upon TCR engagement. A kinetic study revealed that tyrosine phosphorylation of TCRζ occurred initially in the Triton X-100-soluble membrane fraction followed by the accumulation of phosphorylated TCRζ in the GEM. Thus, these results indicate that phosphorylated TCRζ migrates into the GEM domains on T cell activation. We speculate that the GEM microdomains may function as a reservoir of activation signals from triggered TCR.

Recent studies point to glycolipid-enriched membrane (GEM) microdomains as the critical sites for TCR-mediated signal transduction. However, whether the TCR complex is localized in the GEM domain is not well-defined. In the present study, we analyzed localization of the TCR-CD3 complex in the GEM domain by isolating the GEM fraction with sucrose density gradient centrifugation. Although 10% of TCRzeta chains was localized in the GEM fraction, most of the TCR complexes were excluded from the GEM before and after T cell activation, and the amount of TCRzeta in the GEM was not increased after activation. However, the tyrosine-phosphorylated form of TCRzeta was strongly concentrated in the GEM fraction upon TCR engagement. A kinetic study revealed that tyrosine phosphorylation of TCRzeta occurred initially in the Triton X-100-soluble membrane fraction followed by the accumulation of phosphorylated TCRzeta in the GEM. Thus, these results indicate that phosphorylated TCRzeta migrates into the GEM domains on T cell activation. We speculate that the GEM microdomains may function as a reservoir of activation signals from triggered TCR.

At 5 wk after the intraperitoneal infection of murine cytomegalovirus (MCMV) in adult (C3H/He × BALB/c) F1 (CBF1) mice, MCMV-DNA was noted mainly in the salivary glands (SG). Since graft-versus-host reaction (GVHR) is well known as a major risk factor for CMV reactivation, parental BALB/c spleen cells were then intravenously transferred to these mice to induce GVHR. A high copy number of full-length MCMV-DNA was thus observed in the lungs as well as the hearts and livers at 4 to 6 wk after the cell transfer, whereas the copy numbers in SG after the cell transfer were comparable to those before the transfer. It was therefore suggested that the amount of MCMV-DNA noted in these organs had been increased by GVHR. However, no transcripts of MCMV-DNA could be detected. Since a marked expression of mRNA of inducible nitric oxide synthetase (iNOS) was noted in the lungs and the hearts during the course of GVHR, the role of NO in the increase of MCMV-DNA after the cell transfer was next examined. The administration of L-arginine, a substrate for NO, increased the amount of MCMV-DNA in the lungs and the hearts after the induction of GVHR. In contrast, the material which suppressed iNOS induction inhibited the emergence of MCMV-DNA. Therefore, the NO generated during the course of GVHR increased the amount of the viral DNA in the lungs and the hearts of the mice latently infected with MCMV. If the increase in the amount of viral genome is the initial step of viral reactivation from the latent state, then NO would thus trigger the initial step of the reactivation of the DNA virus. As the lungs are the major organ to produce NO after systemic stimulation, the observations of this study may explain why the lungs are the major site of CMV latency and why GVHR triggers CMV reactivation. These findings are thus considered to demonstrate that NO plays a novel role in viral infection.

Motors with low noise characteristics are increasingly in demand due to environmental considerations. The primary source of noise of these motors, in particular of the most widely produced 4- and 6-pole induction motors, is electromagnetic vibration. To gain a better understanding of this specific kind of vibration, the relationship between magnetic flux and mode of vibration is examined from a study of electromagnetic forces and the motor's mechanical response. The flux distribution of the motor is calculated by a finite element method (FEM), and from the results of this study, flux density over the motor's radial direction is analysed in the space and time domains. Similarly, the electromagnetic force waves are calculated by the Maxwell stress method and FEM analysis in the space and time domains. Using Fourier analysis, harmonics of these forces are obtained, and are subsequently used as applied forces in the study of mechanical vibration. The vibration behaviour of the motor caused by electromagnetic forces is simulated using FEM for structure analysis. The modes and amplitudes of vibration provided by these calculations are then compared with experimental results and the strong influence of the frequencies close to natural frequency on the modes of vibration is confirmed.

Abstract: Vertically stacked layer structure is useful for controlling the size distribution of quantum dots. The dependence of the size distribution of quantum dots on the stacking numbers is theoretically and experimentally investigated. We show that the size distribution of quantum dots decreases with increasing the stacking number, and it occurs drastically when the stacking number is changed from 1 to 2. The quantitative analysis on in-plane strain energy distribution is also performed for the explanation.

The gas-phase hydroxyl (OH) radical emission was observed in the thermal decomposition of lithium hydroxide (LiOH). This phenomenon was investigated in a vacuum flow tube reactor at around 2 Torr by the temperature programmed reaction (TPR) experiments at 500−1300 K. The production of OH and other gaseous products was quantitatively investigated by the laser induced fluorescence method and quadrupole mass spectrometry, respectively. The TPR spectra of OH had a peak at 1100−1200 K, which largely exceeded the gas-phase thermodynamic equilibrium. The origin of OH was supposed to be either the surface OH groups on Li2O or the residual LiOH in the LiOH/Li2O solid solution. OH production exceeding the thermodynamic equilibrium was explained by means of the partial equilibrium in the reaction:  LiOH + ¹/4O2  ¹/2Li2O + OH. This phenomenon can be a new route for the OH production from H2O and O2 in cyclic reactions of lithium compounds.

Sapphire plates, cut parallel to an {0001} plane, have been implanted with 300 keV nickel ions to doses ranging from 5×1012 to 1×1017 Ni cm-2 at specimen temperatures of 100, 300 and 523 K, in order to investigate the effect of implantation temperature on the mechanical property changes in sapphire caused by ion implantation. The measured changes in surface hardness, surface fracture toughness and bulk flexural strength were found to depend strongly on the implantation temperature, and were largely correlated with the residual surface compressive stress measured by using a cantilever beam technique. The surface amorphization that occurred only by the implantation at 100 K and at doses larger than ~2×10s15 Ni cm-2 reduced the hardness to ~0.6 relative to the value of the unimplanted sapphire, and considerably increased the surface plasticity. Furthermore, the amorphization was found to involve a large volume expansion of ~30% and to change drastically the apparent shape and size of a Knoop indentation flaw made prior to implantation. This effect was suggested to reduce stress concentrations at surface flaws and hence to increase the flexural strength.

Abstract: After each process of a chemical etching, heat-cleaning, melt-back, or soaking in HC1, the substrate surface of GaSb was characterized by the Auger electron spectroscopy with a simultaneous Ar sputtering to reveal oxide layer structures. An optimum treatment process of GaSb surfaces for low temperature LPE growth of AlGaSb was established. Uniform growth of epitaxial AlGaSb on GaSb is demonstrated for a wide temperature range(from 500‡C to as low as 250‡C).

The electromagnetic noise of a motor is offensive to the ear. Most electromagnetic acoustic noises are generated when natural frequencies of a stator core coincide with or closely parallel frequencies of the magnetomotive forces. Therefore, to minimize such noise, an accurate estimate on natural frequencies of the stator is necessary. In this paper, the stator of a small induction motor is studied as to various factors such as the stator core shape, including a circumferential cut, and stiffness of varnished random winding in stator slots. Furthermore, the effect of coil ends on natural frequencies of the stator core is newly clarified. As a result, in the 2.2kW motor, an equivalent Young's modulus as stiffness of windings in the slots is obtained as being about 1/100th that of copper. Also, study clarifies that coupling vibration arises from the coil end and the stator core. It is found that this coupling vibration can be estimated briefly from a two free degree system.

To investigate changes in glycosaminoglycan (GAG) profiles in human prostatic tissue.

Hydroxyl radical desorption in the heterogeneous catalytic reactions of water or hydrogen with oxygen was examined by laser-induced fluorescence spectroscopy. The catalytic activities of Pt, Al2O3, and basic metal oxides (MgO, CaO, SrO, BaO) supported on Al2O3 were studied in the pressure range 0.1−10 Torr and the temperature range 1100−1300 K. In the case of OH generation from water, the catalytic activities of Pt and all oxides except Al2O3 were very high and the OH concentration reached the equilibrium value within a residence time of 4 ms. In the case of hydrogen oxidation, differences in the catalytic behavior were clearly observed. The surface reaction mechanisms and the effects of Al2O3 and MgO on gas-phase ignition are discussed.

The growth of Pt−Rh alloy crystallites vacuum-deposited on α-Al2O3 substrates by thermal treatment was investigated by atomic force microscopy (AFM) as a function of Rh concentrations. As-deposited Pt thin film without any Rh concentration changed into Pt crystallites dispersed on the substrate by annealing at 800 °C in oxidative and reductive atmospheres. The oxidative atmosphere remarkably enhanced the growth of Pt crystallites, while it is not the case in the growth of pure Rh crystallites. However, when Rh was added to Pt, the crystallites remained very small and highly dispersed on the substrates even after the annealing at 800 °C in an oxidative atmosphere. We also investigated the surface concentration of Pt and Rh by Rutherford backscattering spectroscopy (RBS) and discussed the effect of wettability of Rh oxide as a key role in inhibiting the growth of Pt−Rh crystallites.

Thermal stability and the effect of water-coordination of a silicoaluminophosphate, SAPO-34, were investigated on the basis of multinuclear NMR studies. Crystalline silicoaluminophosphates (SAPOs) have been found as a new family of synthetic molecular sieves. The expected applications of SAPOs are as adsorbents and catalysts. Thermal stability is one of the crucial factors in applying SAPOs as automotive exhaust catalysts. 27Al-, 29Si-, and 31P-NMR spectra and XRD as a function of temperature showed the microporous structure of SAPO-34 to be stable up to 1000°C. The effect of water-coordination on the 27A1- and 31P-NMR spectra also showed the adsorptive properties of SAPO-34 to be stable up to 1000°C. In this paper. SAPO-34 was found to be promising as an automotive exhaust catalyst with a microporous structure and high heat resistance.Copyright 1993, 1999 Academic Press