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Seasonal variations of water-balance components at an experimental watershed
were measured for three hydrologic years. Snowfall accounts for 47% of the
annual precipitation, and snowmelt runoff comprises 45% of the total runoff.
Evaporation changed markedly during the season; it increased during May to
August, decreased in September and October, and was negligibly small during
the period of snow cover in winter. Losses due to evaporation reached half
of the precipitation during summer, and total loss is about 26 % of the
The Munich Dust Counter (MDC) is a scientific experiment on board the MUSES-A mission of Japan measuring cosmic dust. The satellite HITEN of this mission has been launched on January 24th, 1990 from Kagoshima Space Center. Here the present status of the MDC experiment is summarized. The number of dust particles measured so far is presented together with first and preliminary results of flux calculations and spatial as well as directional distributions of cosmic dust particles measured until July 25, 1990. A clear evidence of particles coming from the inner solar system (beta-meteoroids) already has been found. These are compared to particles coming from the apex direction.
The Munich Dust Counter (MDC) is a scientific experiment on board of the MUSES-A mission of Japan. It is the result of a cooperation between the Institute of Space and Astronautical Science (ISAS) of Japan and the Chair of Astronautics of the Technische Universität München (TUM) of Germany. The MDC is an impact ionization detector designed to determine mass and velocity of cosmic dust. Here a short overview over the MUSES-A mission is given to show the measurement situation of the MDC experiment. The measurement principle of the instrument together with a discussion of the scientific objectives and the design of the experiment is summarized.
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.
It is difficult to get a real scale image of the solar system through lecture. A scale model is a classical and one of good solutions (e.g. Handa et al.2003, Handa et al.2008). Through this model, people living in or visiting to the city can physically understand the scale of the solar system. This scale gives 1 cm for Earth's diameter and 115 m for 1 AU. However, some gadget is required to make it attractive for public citizens.
For appropriate safety assessment of TRU waste disposal, the dominant chemical species of 14C-gas was studied. [1,2-14C] sodium acetate was added to flooded paddy soil samples, and the content of 14C in the soil, solution, and the emitted CO2 gas during incubation period was determined. Recovery ratios of the total 14C activity to the initial 14C activity were 97.9% at day 1, 86.4% at day 3, and 83.5% at day 7 of incubation. The result of the day 1 means that the emitted 14C-gas was almost 14CO2. At day 7 of incubation, about 16.5% of 14C was failed to recover. Even if the unknown 14C was gases other than 14CO2, the dominant chemical species of the emitted 14C-gas will be 14CO2, because the recovery ratio of the 14CO2 was 48.9% (¿16.5%). Sodium 2-bromoethane-sulfonate was used to ensure the emission of CH4, but there was no effect of the regent to the recovery ratio of 14CO2. Methane emission may be little under our experimental conditions. These results suggest that the dominant chemical species of the emitted 14C-gas from the flooded paddy soil samples was 14CO2.
Metal deposition on a p-sexiphenyl (6P) film was studied by ultraviolet photoelectron spectroscopy (UPS), metastable atom electron spectroscopy (MAES), and X-ray photoelectron spectroscopy (XPS). The deposited metals were Au, Mg, and several alkali metals (K, Na, Rb, and Cs). No chemical reaction between 6P and Au or Mg was observed in the measured spectra, while additional gap states appeared in the UPS and MAES spectra by deposition of the alkali metals. The diffusion of Au and Mg atoms into the 6P film was observed in the MAES spectra. We found the trend of the vacuum level shift is different between the systems of the 6P on the Au and its reversed systems (Au on the 6P film), suggesting the different formation of the interface depending on the deposition sequence.
The fundamental problems of applying high-Tc superconductors to power transmission lines were studied, and prototypes of multilayer-wound conductors were fabricated and evaluated.
Multifilamentary silver sheathed wires have good anti-strain. properties. A 61-filament bismuth(2223) wire proved to maintain 90% of initial transport current property after 150 cycles of bending (bent-straightened-bent reversely-straightened) with 0.18% strain. A 61-filament wire of 114m unit-length was produced and proved to have a Jc of 9,700 A/cm2 with an Ic of 9.34A for the whole length at 77.3K.
Using these multifilamentary wires, prototypes of multilayer-wound conductors were produced by the react-and-wind technique. A 1.4m long three layer-wound conductor could carry 590A (Jc=7.020A/cm2) in liquid nitrogen.
These results indicate that the basic problems of high-Tc superconductor application to power transmission lines will be overcome using this technology.
One of the most important subjects for semiconductor packages is preventing cracks which occur when the entire package is exposed to a soldering temperature of 215 to 260°C in the surface mounting technology. Cracking, as seen during temperature cycling tests is also a problem to be addressed. This paper reports the design of epoxy encapsulating compounds for highly reliable semiconductor devices which require the following properties: (1) toughness of matrix resin, (2) low moisture absorption, (3) high adhesion to insertions, and (4) reduction of thermal stress. The moisture absorption was lowered and the toughness was improved by using hydrophobic epoxy resins and high filler loading. The latter reduced the thermal stress, and it was effective for lowering the moisture absorption and increasing the fracture toughness of molding compounds. The reliability tests results were also considered in terms of physical properties of molding compounds.
The localized density of states (LDOS) at interfaces between intrinsic silicon and silicon nitride (Si3N4 films are studied using transient voltage spectroscopy (TVS). In the TVS technique, the transient of the voltage across a MIS-diode after a trap filling voltage pulse is measured using a high-impedance voltage probe. This allows us to make a precise measurement of the LDOS at undoped Si/insulator interfaces. The LDOS in a-Si:H/Si3N4systems has a broad peak around the energy of 0.9 eV below the conduction-band edge. A modification of the LDOS at a-Si:H/Si3N4 interfaces by bias-annealing is clearly observed using this technique. The results are consistent with the defect pool model. The LDOS in laser annealed poly-Si/Si3N4 systems has a peak centered 0.6eV below the conduction-band edge, which seems to be the Si dangling bond states in the poly-Si films.
The low cycle fatigue behavior at 25°C and 825°C of three advanced nickel-base eutectics is described. Fatigue lives are shown to obey a linear relation with plastic strain range (Coffin-Manson relation) but lives are much lower than are observed for conventional metals and alloys. Cyclic hardening and softening were observed in each alloy at 25 °C; however, this behavior differs from the classical saturation behavior observed with isotropic materials.
This paper presents the current advances in the development of materials in the field of telecommunication wiring together with the background which created the need for the new technologies. The background is somewhat unique to the current socio-economical situation of Japan. The key technical areas, which are addressed in this paper, are; (1) fibers for transmission of over 1 Tbps by utilizing WDM (wavelength division multiplexing), (2) fibers for fiber amplifiers to replace repeaters within trunk lines, (3) high density cables with over 1000 fiber counts, (4) ABF (air blown fiber) for access system, (5) plastic optical fibers wiring in premises or offices operating at the transmission speed of over 200 Mbps.
The vacuum level shift A was determined by Kelvin probe method for TPD/metal systems prepared in ultrahigh vacuum (TPD: N, N'-bis(3-methylphenyl)-N, N'-diphenyl-[1, 1'-biphenyl]-4,4'-diamine). The energy of the vacuum level sharply changed at the initial stage of depositing TPD on the metal substrates, and further bending was not observed up to 100 nm thickness of TPD. This result is consistent with our previous studies of ultraviolet photoelectron spectroscopy. These results indicate the invalidity of traditional model with a common vacuum level at organic/metal interface. We discussed the dependence of the vacuum level shift on the work function Φm of the metal substrate (Au, Cu, Ag, Mg, and Ca). A liner correlation between Δ and Φm was observed only in the region of 3.8 eV < Φm < 4.5 eV, indicating that Fermi level alignment is not achieved at least for some interfaces. We found that Δ for TPD film on the air-exposed metal substrate is smaller than that of TPD on clean metals and was observed a liner relation between Φm and Δ except for the Cu substrate.
Structural relaxation around free volume in Zr50Cu40Al10 bulk metallic glass (BMG) during isothermal annealing at 473, 573 and 673 K which are below glass transition temperature Tg =675 K have been investigated by positron annihilation lifetime (PAL) and coincidence Doppler broadening (CDB) measurements. The trends of change in positron lifetime, which correspond to the size of free volume at each annealing temperature, have a good correlation with their density change. These annealing processes obey a stretched exponential relaxation function (KWW: Kohlrausch-Williams-Watts law). Fitting parameters of KWW function, with relaxation time t0 and β, in each temperature were determined. These relaxation parameters depend on the annealing temperature, suggesting the distribution of activation energy for structural relaxation. Moreover, the profile of electron momentum distribution around free volume derived by CDB spectrum during annealing showed no appreciable change at each temperature. These facts suggest that long range chemical ordering, particularly around the free volume, dose not take place essentially.
In various organic electronic devices, interfaces formed by organic layers can play important roles. We have been studying various organic interfaces for clarifying their structure and electronic structure. In this talk, we will report our recent study of the effect of various types of doping for a variety of dopants – residual impurity, atmospheric gases, and metallic and organic intentional dopants. In particular, detailed and quantitative information about the effect of oxygen from the viewpoint of electronic structure was obtained for titanyl phthalocyanine (TiOPc), and the results corresponded well with the recent report of atmospheric effect on orga nic field effect transistor.
Mango (Mangifera indica L.) is an important fruit crop with a long cultivation history in Myanmar. This study evaluated the genetic variation within two economically important traditional varieties, ‘Yin Kwe’ and ‘Sein Ta Lone’, and the relationship between genetic variation and propagation practices. Genetic variation was estimated by genotyping 94 individuals with 12 single sequence repeat markers. ‘Yin Kwe’ (n = 53) showed higher levels of observed heterozygosity (Ho = 0.59) and average genetic distance among individuals (Da = 0.29) than did ‘Sein Ta Lone’ (n = 41; Ho = 0.45; Da = 0.09). The differences between the two varieties at the DNA level were significant (Fst = 0.44). The broader genetic background in ‘Yin Kwe’ compared with ‘Sein Ta Lone’ was also demonstrated by neighbour-joining and principal coordinates analyses. Differences in variety uses and propagation practices were determined by interviewing local specialists in Lower Myanmar (southern Myanmar). ‘Yin Kwe’ was often used as a rootstock for ‘Sein Ta Lone’. Clonal propagation by grafting was observed frequently for ‘Sein Ta Lone’ but never for ‘Yin Kwe’. The differences in genetic variation between these two varieties might have been caused by the propagation practices for each variety, which result from their respective uses.
This paper summarizes research activities in National Institute of Radiological Sciences (NIRS) for evaluation of the radiation effects on selected terrestrial and aquatic organisms as well as the ecosystems. Seven organisms, conifers, fungi, earthworms, springtails, algae, daphnia and Medaka are presently selected to study. For the estimation of possible radiation dose, transfers of radionuclides and related elements from medium to organisms are evaluated. Dose-effect relationships of acute gamma radiation on the survival, growth, and reproduction of selected organisms have been studied. Studies on the effect of chronic gamma radiation at low dose rate were also started. In order to understand the mechanism of radiation effects and to find possible indicators of the effects, information of genome- and metagenome-wide gene expression has been collected. Evaluation of ecological effects of radiation is more challenging task. Study methods by using three-species microcosm were established, and an index for the holistic evaluation of effects on various ecological parameters was proposed. The microcosm has been simulated as a computer simulation code. Developments of more complicated and practical model ecosystems have been started. The Denaturant Gradient Gel Electrophoresis (DGGE) has been applied on soil bacterial community in order to evaluate the radiation effects on soil ecosystems.
For appropriate safety assessment of TRU waste disposal, gasification ratios and distribution coefficients (Kd) of 14C labeled [1, 2-14C] sodium acetate were determined by batch experiments for a Japanese paddy soil sample. Approximately 60% of the total added C-14 was released from the flooded paddy soil into the air as gas forms during 7 days shake-incubation periods. In the present study, the paddy soil was contacted with deionized water and well water, and the lower gasification ratio was found for the well water sample. The similar result was observed for the Kd values. Values of Kd varied from 51 to 138 mL g-1. The lower values were observed when the soil was contacted with well water. When the microorganisms in the samples were killed by glutaraldehyde, both gasification ratios and Kd values were nearly zero. These results suggested that microorganisms responsible for the behavior of C-14 in biosphere. In addition, water characteristics such as dissolved ions, pH and electrical conductivity would affect the gasification ratio and the Kd values.
Mathematical computer model is developed to simulate the population dynamics and dynamic mass budgets of the microbial community realized as a self sustainable aquatic ecological system in the tube. Autotroph algae, heterotroph protozoa and saprotroph bacteria live symbiotically with interspecies' interactions as predator-prey relationship, competition for the common resource, autolysis of detritus and detritus-grazing food chain, etc. The simulation model is the individual-based parallel model, built in the demographic stochasticity, environmental stochasticity by dividing the aquatic environment into patches.
Validity of the model is checked by the multifaceted data of the microcosm experiments. In the analysis, intrinsic parameters of umbrella endpoint regarding to lethality are manipulated at the individual level, and tried to find the population level, community level especially focused on predator-prey relationship, and revealed the indirect effect of chronic exposure of radiation on the probability of Tetrahymena's extinction.