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To address its temperature and density we made observations of the galactic plane in CO (2-1) line with VST1 and VST2. Using a kinetic model we estimate the volume emissivities and the line intensity ratio as a function of galactocentric radius. Using data in the first and 4th quadrants separately we got shallow gradient in the both quadrants; at the smaller radius is the higher in ratio. The gradient is contributed by less bright pixels in the l-v diagram, suggesting molecular gas in interarm is different along the galactocentric radius but in arm is not.
Physical conditions of molecular gas are key parameters to the formation rate and initial mass function of stars formed in molecular clouds. The ongoing Tokyo-NRO survey has been observing the Galactic CO (J=2–1) emission with a beamsize matched to the Columbia CO (J=1–0) survey. Intensities of the two lines should reflect physical conditions of the CO-emitting gas. An out-of-plane survey of the inner Galaxy which covers from 20° to 60° in galactic longitude and from −1° to +1° in galactic latitude with grid spacings of 0.25° has already been made (Sakamoto et al. 1994). Its coverage is large enough to draw conclusions on global properties of molecular gas in the inner Galaxy.
Numerical modeling of the interstellar gas in galaxies is an effective approach to infer galactic gravitational structure. This is because the dynamical behavior of gas is very sensitive to the background gravitational potential. Since the dynamical resonances depend closely on the mass distribution and the pattern speed of the non-axisymmetric component, it is possible to determine these dynamical parameters by comparison of numerical simulations and gas observations.
The combination of X-ray and Sunyaev-Zel'dovich (S-Z) effect observations toward cluster of galaxies gives the independent estimation of Hubble constant (Sunyaev and Zel'dovich 1970). The measurement of S-Z effect is one of the most difficult observations in radioastronomy because of the weakness of the effect, ΔT = 0.1 × 1 mK (e.g. Rephaeli 1995). Because the field of view of the exist interferometers is smaller than the extended distribution of S-Z effect of low redshifted clusters, single-dish telescopes gain an advantage over interferometers. In addition, to reduce the contaminations from Galaxy and galaxies in the cluster, the mm-wave observation is preferable. Thus, we have started the project of S-Z effect observation with the Nobeyama 45-m telescope, which is the largest mm-wave telescope in the world. Our scientific goal is reliable measurement of S-Z effect of many clusters. To realize this we have made a multi-feed PCTJ-SIS mixer receiver at 40 GHz as a sophisticated tool for the observation of S-Z effect (Noguchi et al. 1995, Kasuga et al. 1995, Tsuboi et al. 1997).
We report Hα imaging observations of nearby galaxies with the Kiso Schmidt telescope. For spiral galaxy NGC 628, we found no clear correlation between Hα and CO intensities, and we discuss the star formation efficiency of this galaxy. No nuclear Hα emission in this galaxy was detected. This is consistent with spectroscopic observations which indicate that the nuclear region is in the post starburst phase. We also describe the Hα image of Hickson's compact group 92 in which diffuse emission is detected extending within the group system.
Zizina emelina (de l'Orza) is listed on Japan's Red Data List as an endangered species because of loss of its principal food plant and habitat. We compared parts of the mitochondrial and nuclear genes of this species to investigate the level of genetic differentiation among the 14 extant populations. We also examined infection of the butterfly with the bacterium Wolbachia to clarify the bacterium's effects on the host population's genetic structure. Mitochondrial and nuclear DNA analyses revealed that haplotype composition differed significantly among most of the populations, and the fixation index FST was positively correlated with geographic distance. In addition, we found three strains of Wolbachia, one of which was a male killer; these strains were prevalent in several populations. There was linkage between some host mitochondrial haplotypes and the three Wolbachia strains, although no significant differences were found in a comparison of host mitochondrial genetic diversity with nuclear genetic diversity in Wolbachia-infected or -uninfected populations. These genetic analyses and Wolbachia infection findings show that Z. emelina has little migratory activity and that little gene flow occurs among the current populations.
Monitor of All-sky X-ray Image (MAXI) on board International Space Station is capable of
observing gamma-ray bursts (GRBs) and sending notices of GRBs or other transient events,
using real time connection to the ground. MAXI observed 32 GRBs or short X-ray transients
as of the end of September 2012. Among them, eleven events were simultaneously detected by
other satellites. The observed rate of the MAXI GRBs is about one event per month. This
rate is comparable to a past observation with larger effective area and larger field of
view. The fact indicates that MAXI has better sensitivity to observe GRBs because of low
background. The distribution of the spectral hardness of MAXI GRBs is similar to the
results of a past instrument, which is sensitive to similar energy range.
This study examined surface modification of solder resist and dry film resist using 60 Hz nonequilibrium atmospheric pressure plasma with O2/N2 mixing gas. Results show that the plasma discharge condition at O2/N2 mixing ratio of 0.1% was the best for surface modification for both materials, and the surfaces were modified sufficiently at 0.45 m/min package substrate transportation speed. From the plasma diagnostics by Vacuum Ultraviolet Absorption Spectroscopy (VUVAS) and Optical Emission Spectroscopy (OES), it was found that the behaviors of the oxygen radical density and NO-γ emission intensity correlate strongly with surface modification. The extremely high oxygen radical density around 4.7 × 1013 cm-3 was obtained at O2/N2 mixing ratio of 0.1%. The electron density was 2.5 × 1015 cm-3 that is two digits more than that of the conventional atmospheric pressure plasma such as Dielectric Barrier Discharge (DBD). The solder resist surface with the plasma treatment was analyzed by X-ray Photoelectron Spectroscopy (XPS), and it was clarified that material surface was modified by hydrophilic group generation owing polymer chain oxidation with oxygen radical.
Disaster preparedness is one of the national priorities. In Japan, disaster medicine is defined as a part of the national medical plan initiated by Ministry of Health, Welfare and Labor. The Japan Medical Association is the largest professional physicians' group in Japan, and has contributed to all kinds of disaster relief work regionally and nation-wide for years. Based on past successes, the Japan Medical Association proposes a new disaster action plan named Japan Medical Association Team (JMAT). The primary mission of JMAT is to deploy to the disaster scene requested and work for disaster relief. JMAT covers the acute to sub-acute phase of disaster response, and also collaborate with other agencies. In the preparation and mitigation phases, the Japan Medical Association work for establishing mutual disaster aid partnerships, disaster plans, networks with other agencies, team building, disaster medicine training and education, etc. In Japan, the Disaster Medical Assistant Team (DMAT) has been established based on the experience of the 1995 Kobe Earthquake, when lots of preventable trauma deaths occurred because of delayed medical response. The mission of DMAT is to deploy to the scene immediately and triage/transfer the most serious disaster victims outside the scene for advanced medical care. DMAT covers the first 48 hours of disaster response phase, and then JMAT takes charge of the work. JMAT will also respond to chemical, biological, radiological and nuclear disasters, and international humanitarian work. The present issues of establishing JMAT are 1.training and education for Japan Medical Association members, 2.establising cooperation with other agencies, and 3.having presence at the Central Disaster Committee, Cabinet Office, Government of Japan.
A “0-0 type” multiferroic BaTiO3-NiFe2O4 (BT-NF) composite thin film was prepared on SrRuO3/(La,Sr)MnO3/CeO2/YSZ/Si(001) substrate using pulsed laser deposition (PLD). Epitaxial growth of the film was confirmed using x-ray pole figure measurements. Cross-sectional TEM observations revealed that the crystal structure and morphology of the BT-NF composite thin film depends on the oxygen pressure during deposition. The film deposited at 1.0×10-2 Torr has smaller grains than that deposited at 1.0×10-1 Torr. The magnetic and ferroelectric properties of BT-NF composite thin film were correlated with the microstructure that was controlled by oxygen pressure during deposition. The film deposited at 1.0×10-2 Torr had paramagnetic properties with less polarization than the film deposited at 1.0×10-1 Torr.
Bending tests of Diamond-Like Carbon (DLC) nanopillars fabricated by Focused Ion-Beam assisted Chemical Vapor Deposition (FIB-CVD) were carried out in a scanning electron microscope (SEM) to investigate their mechanical behavior. Special attention was paid on the effect of the specimen size. The nanopillars with nano-sized diameter and micro-sized length were grown using spot irradiation without scanning FIB. The diameter of the nanopillars was changed in the range of 100 ~ 1000 nm by changing the magnitude of defocusing FIB.
In the bending tests, brittle fracture was observed for the nanopillars with diameter of 1000 nm. On the contrary, large deformation without brittle fracture was confirmed in the specimens with diameter of 300 nm. In addition, the pillar recovered its original shape after unloading without any permanent deformation even after the large deformation.
Transmission electron microscope (TEM) analysis revealed that the pillars had uniform amorphous structures regardless of the diameters if the FIB was defocused during processing. In addition, similar gallium (Ga) content and sp2/sp3 fraction were observed in both specimens. These results indicate that difference in microstructures cannot be the reason for that in mechanical behavior. In other words, it must be caused by the intrinsic size effect on the mechanical properties of DLC fabricated by FIB-CVD process.
Influence of processing condition on mechanical and structural properties of diamond-like carbon (DLC) by focused ion-beam chemical vapor deposition (FIB-CVD) method was investigated. The DLC specimens were produced under conditions of varying supplied amount of material gas and probe current of FIB. Volume determination results of DLC structures indicated that a deposition rate was increased with both the amount of gas and the probe current. To evaluation of mechanical property, indentation hardness was measured by a nano-indentation tester. From evaluation of mechanical property, it was found that the indentation hardness was sensitive to the processing condition, showing in the range of 8-13 GPa. The hardness of DLC structures was seemed to be lower when etching process higher contributed for formation process. Crystallographic structure of DLC remained amorphous even though the mechanical properties varied widely. Results of hydrogen concentration measurement indicated that increase of hydrogen concentration might lead to decrease of hardness.
The influence of lateral critical current density (Jc) distributions on AC transport losses in self-fields at 77 K have been investigated on the Ag-sheathed (Bi, Pb)-2223 multifilamentary tapes with different filament arrangements. The trapped magnetic field distributions in a remanent state on the tape surface measured by a scanning Hall sensor depend on the filament arrangements and gradually deviate from the calculation results of magnetic profile without any Jc variations in their cross sections. The transport loss values are strongly influenced from the filament arrangements in each tape, although the main contribution to the losses comes by the hysteresis loss in the superconductor. These results are explained by the calculation results of the shape of field-free core and flux-penetration-regions, varying with filament arrangements and local Jc distributions along a width direction.
We evaluated structural and electrical characteristics of undoped poly-Si oxide films. Poly-Si films made by solid phase crystallization at 600-900°C from undoped amorphous Si films were oxidized to form oxide layers of 140nm thickness. We observed protuberances on the surface of poly-Si layers after oxidation. Poly-Si oxide layers also generated protuberances above the protuberances of poly-Si films. The number of protuberances per unit area is larger in the case of high temperature crystallization. The measurement of current through the poly-Si oxide films shows that the conductivity of poly-Si oxide films depends on crystallization temperature of poly-Si films in the case of positive gate bias. When the gate is biased negatively, current through the poly-Si oxide films remained almost constant regardless of crystallization temperature. We find that poly-Si crystallized at lower temperatures offers poly-Si oxide films of lower leakage current in the case of electron injection from undoped poly-Si layers. The lower leakage current is due to highness of energy barrier for electron at undoped poly-Si/poly-Si oxide interface.
The preparation and properties of hydrogenated amorphous silicon thin film transistor arrays for active matrix liquid crystal displays are reported. The effect of amorphous silicon film preparation conditions on the field effect mobility of thin film transistors was investigated. The dry etching rate of silicon nitride film was studied.The thin film transistor arrays have 408 ˜ 640 transistors on the first version and 450 ˜ 640 ˜ 3 transistors on the second version. The liquid crystal panel fabricated using the first version arrays showed good characteristics.
Photoemission spectra (XPS and UPS) of As-covered Si (001) surfaces prepared at high (>600ºC) and low (<450ºC) temperatures and GaAs epilayers subsequently grown on them were measured without exposing to air. It was found that the surface electronic structures of As/Si prepared at the low temperature are different from those of the high temperature sample, the spectra of which can be interpreted as a symmetric dimer model. Differences were also observed between the GaAs epilayers on the As—covered Si surfaces prepared at the high and low temperatures. The temperature dependence of the surface and interface structures are discussed.
We have employed a 2.45 GHz electron cyclotron resonance (ECR) plasma source to deposit single-crystal thin films of titanium nitride onto MgO substrates of (100) orientation. During deposition the ECR plasma beam delivering a mixture of excited species of molecular and atomic nitrogen ions, strikes a substrate while an electron beam deposits on the same substrate species of titanium. We have studied the formation of films at substrate temperatures of 200, 400, and 600°C, as well as at room temperature. X-Ray diffraction (XRD) revealed that a cubic Bl phase of titanium nitride forms predominantly at all the temperatures explored. Both channeling and Rutherford backscattering spectroscopy (RBS) showed epitaxial layers forming at the temperature as low as 400°C. The minimum relative backscattering yield, χmin decreased as the temperature increased, with the best result of 7.3% obtained for the film deposited at 600°C. Biasing the substrates with either negative or positive voltage at room temperature directly affects film crystallography.
Titanium silicide (TiSix), used as polycide gate consists of TiSi1.1 and amorphous silicon (a—Si), was deposited by Plasma Enhanced Chemical Vapor Deposition method (PE—CVD). The effect of a—Si layer in PE—CVD Ti polycide gate dielectrics has been studied. In order to evaluate the a—Si layer effect, three types of samples were prepared on gate SiO2 film with following structures: a) a—Si / TiSil.1 / a—Si / phosphorus (P) doped poly—Si, b) a—Si / TiSi1.1 / non—doped poly—Si / P doped poly—Si and c) a—Si / TiSi1.1 / P doped poly—Si, respectively. Furthermore, in order to avoid the influence of native oxide existence at the interface, the pre—cleaning treatment was performed in—situ on the poly—Si film surface before TiSi1.1 film deposition. The gate dielectric strengths of these samples indicate that the gate dielectric degradation in PE—CVD Ti polycide gate is greatly dependent on Si under layer crystallization. It is effective using a—Si film as the under layer in decreasing the gate dielectric degradation. This is due to the Ti oxide interlayer, formed at the interface of TiSi2.0 and poly—Si films, whichrestrains the TiSix local penetration.