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Small scale hydropower energy goes a long way to fire up community development. Until 1920-30s, Japanese hydropower techniques had been established on a global level in each local area. However, after the second World War, the main energy resource was changed. This has resulted in a local decline in micro-hydro technical expertise and fewer waterwheel makers throughout Japan. At the present, we are going to work to re-make small scale hydropower technologies and markets. In this paper, we discuss and propose improvements to the “Japanese” small scale hydropower technology and production techniques, especially Pelton type wheel. The Pelton wheel technology of Nepal was freely available in the public domain so we decided to design a system based on that. We decided to designed by 3D-CAD and to make our Pelton buckets using a 3D printer. We compared the power generation capacity of our waterwheel with one purchased from New Zealand to investigate its effectiveness and efficiency. In our results of the experiment, the power generation curves for each turbine are approximately equal. The power increases continuously with increases in the flow rate. The maximum power generated by each turbine is approximately the same. This shows that it is possible to design a Pelton bucket that has a power generation efficiency comparable to a purchased bucket. The next step, the Pelton turbine designed in this study was chosen to be included in the Itoshima micro-hydro power generation system. So we scaled up and redesigned the Pelton turbine. In addition, we conducted a survey involving waterwheel makers regarding connecting to cost reduction. Using a 3D printer has the following advantages: 1.) Design deficiencies and failed designs can be identified at an early stage. 2.) Different forms of waterwheel can be made at low cost and in a short amount of time, which can then be used to run water experiments.

Phytoliths and charcoal preserved in two soil sections in northern part of Aso Caldera, central Kyusyu, Japan revealed grassland and fire history since the late-glacial. The phytolith assemblages were divided into two significant zones, respectively. Phytolith assemblages show that the grassland vegetation, composed mainly of Sasa species, has continued since the late-glacial. The grassland compositions changed from Sasa type to Pleioblastus type around 7.5 cal ka. Charcoal records indicate that fire occurred at least in the early Holocene and continued to the present. Judging from the phytolith and charcoal records, the establishment of grassland may have been affected by not only climate changes and volcanic activities, but also fire since the early Holocene. Around the Aso Caldera, numerous prehistoric archaeological sites since the late-glacial have been discovered. Therefore, the occurrence of fire during the Holocene was possibly caused by human activities, and fire influenced the establishment of grassland. The results are important for understanding the relation between the fire and grassland vegetation in the regions where human activity has continued.

Soft X-ray emission and absorption spectra in the C K region of amorphous carbon films systematically deposited by RF, ion-beam, and ECR sputtering under various deposition conditions were measured using highly brilliant synchrotron radiation. A broad main peak and a high-energy shoulder were observed in the emission spectra, and a fine structure consisting of at least five peaks was observed in the absorption spectra. By analogy to the occupied/unoccupied C2p-DOS obtained by DV-Xα molecular orbital calculations of simple cluster models composed of sp 2 and sp 3 carbon atoms, we approximately explained the spectral features in the measured X-ray emission spectra by σ and π bonds and estimated the fine structures in the absorption spectra by the hybridized unoccupied molecular orbitals formed by the local-structures composed of sp 2 and sp 3 carbon atoms.

Coloration reactions between nitrogen dioxides (NO2) and diazo-coupling reagents have been shown to occur in the nano-pores of porous glass. We introduced sulfanilamide and N,N-dimethyl-1-naphthylamine as diazo-coupling reagents into porous glass. This organically doped porous glass sensor had one specific peak near 525 nm in the visible region and showed large changes in absorbance after exposure to NO2. We investigated the humidity dependence of its sensitivity during exposure to NO2 in an artificial environment. The sensitivity was almost constant from 35% to 70% RH. Thus, our simple NO2 detection system using the porous glass sensor, a light-emitting diode, and a photodiode was able to determine the hourly variations in NO2 concentration at the ppb level in an actual environment without being seriously affected by humidity in the range between 35% and 70% RH.

High-resolution soft X-ray emission and absorption spectra in the C K region of hydrofullerene, which probably consists mainly of C 60 H 36 , were measured using highly brilliant synchrotron radiation to identify its molecular structure and electronic structure. Comparison with the C2p-DOS spectra, calculated by discrete variational (DV) Xα molecular orbital calculations, of three possible C 60 H 36 isomers, showed that the measured X-ray spectra approximately agreed with the calculated C2p-DOS spectra of the T-symmetry isomer. The X-ray spectral features were explained by the electronic structure hybridized between the sp 2 and sp 3 carbon atoms of the T-symmetry C 60 H 36 .

We have investigated the relationship between solar wind speeds and the energetic proton intensity associated with corotating interaction regions (CIR) observed at 1 AU during 1973 – 1995 using NSSDC Data. The speed-difference between the high-speed solar wind and the slow-speed solar wind, which forms CIR at outer heliosphere, shows a good correlation with the peak intensity of 1 – 2 MeV protons during the solar quiet periods. The speed-difference is probably related to the shock strength of the reverse shock of the CIR formed beyond ∼ 1 AU. We have also found the solar activity dependence of the correlation between these quantities in CIR events during the period between 1973 and 1995. The intensity of CIR particles during the solar active periods is higher than that during the quiet periods, suggesting that the density of seed particles in CIR events during the solar active periods is larger than that during the solar quiet period.

A new type of real-time radiation monitoring device, RRMD-III, consisting of three double-sided silicon strip detectors (DSSDs), has been developed and tested on-board the Space Shuttle mission STS-84. The test succeeded in measuring the linear energy transfer (LET) distribution over the range of 0.2 keV/micrometer to 600 keV/micrometer for 178 h. The Shuttle cruised at an altitude of 300 to 400 km and an inclination angle of 51.6 degrees for 221.3 h, which is equivalent to the International Space Station orbit. The LET distribution obtained for particles was investigated by separating it into galactic cosmic ray (GCR) particles and trapped particles in the South Atlantic Anomaly (SAA) region. The result shows that the contribution in dose-equivalent due to GCR particles is almost equal to that from trapped particles. The total absorbed dose rate during the mission was 0.611 mGy/day; the effective quality factor, 1.64; and the dose equivalent rate, 0.998 mSv/day. The average absorbed dose rates are 0.158 mGy/min for GCR particles and 3.67 mGy/min for trapped particles. The effective quality factors are 2.48 for GCR particles and 1.19 for trapped particles. The absorbed doses obtained by the RRMD-III and a conventional method using TLD (Mg(2)SiO(4)), which was placed around the RRMD-III were compared. It was found that the TLDs showed a lower efficiency, just 58% of absorbed dose registered by the RRMD-III.

A new type of Real-time Radiation Monitoring Device, RRMD-III, consisting of three double-sided silicon strip detectors (DSSDs) has been constructed and used onboard the Space Shuttle mission STS-84. The Space Shuttle cruised at an altitude of 300–400 km and an inclination angle of 51.6° for 221.3 h. RRMD-III succeeded in measuring the linear energy transfer (LET) distribution over the range of 0.2– 600 keV / μ m for 178 h . The obtained LET distribution of particles was investigated in detail by classifying it into galactic cosmic ray (GCR) particles and trapped protons in the South Atlantic Anomaly (SAA) region. The result shows that GCR particles contribute 60% to the total dose equivalent. The total absorbed dose rate during the mission was 0.516 mGy / day , the effective quality factor was 1.81 by ICRP-Pub.26, and the dose equivalent rate was 0.935 mSv / day . The average absorbed dose rates are 0.120 μGy / min for GCR particles and 4.80 μGy / min for trapped protons. The effective quality factors are 3.16 for GCR particles and 1.19 for trapped protons. RRMD-III data were also compared with the data of the tissue equivalent proportional counter (TEPC), proving that RRMD-III is a reliable device for deriving the true-LET distribution in real time for evaluating space radiation.

To develop an NO2 sensor that can measure the NO2 concentration in the atmosphere, we studied changes in fluorescence intensities of dyes impregnated in porous glass when exposed to NO2 in N2 as the first step. The NO2 sensing materials were Squarylium dye 1, Squarylium dye 2, and Rhodamine B. We found that fluorescence quenching by NO2 occurred even in porous glass. The fluorescence quenching (F0/F) increased as the NO2 concentration increased in the range of 0.2–12.3 ppm, with an almost linear relationship. The minimum detectable concentration of NO2 was 0.2 ppm.

Coloration reactions have been found between nitrogen dioxide (NO 2 ) and organic compounds, such as aromatic amine derivatives, impregnated in porous glass. A single absorption peak in the visible region was detected after the reactions for all compounds. Linear relationships were obtained between environmental NO 2 concentrations and absorbance changes at peak wavelength for some compounds. A system is proposed for detecting low-levels of NO 2 using these coloration reaction in porous glass. Our designed system is composed of an organically-impregnated porous glass sensor and a simple absorbance meter having a single-wavelength light source. It was clarified that environmental ppb-levels of NO 2 could be detected using our system and that values for hourly average concentrations of NO 2 obtained by our system agreed well with those obtained using commercial analytical instruments. A coloration reaction mechanisms are also proposed based on the experimental results obtained.

Theoretical C K and N K X-ray emission/absorption spectra of fullerene-like-structured carbon nitride (C 24 N 36 ) clusters were obtained using discrete-variational (DV)-Xα molecular orbital calculations. These calculations predicted that the energy widths of the C K and N K X-ray emission peaks would be about 8 and 6 eV, respectively; three low-energy satellites would appear in each emission spectrum; and there would be a narrow HOMO-LUMO energy gap of 0.38 eV. These theoretically predicted X-ray emission/absorption spectra will be useful in the synthesis and characterisation of fullerene-like carbon nitrides.

Coloration reactions for NO 2 detection were demonstrated to occur in the pores of porous glass. Porous glass chips impregnated with a new combination of coupling reagents (sulfanilamide as a diazotizing reagent and N , N -dimethyl-1-naphthylamine as a coupling reagent) showed large absorbance changes after exposure to NO 2 in both artificial and actual environments, indicating their applicability to ppb-level NO 2 detection. A simple sensor device, consisting of this doped porous glass, a light-emitting diode as a light source, and a photodiode as a detector, can detect hourly changes in ppb-level NO 2 concentrations, which has previously been possible only by using large analytical instruments.

The energy spectra (40 to 300 MeV/n) of galactic cosmic ray particles (C, N, O, Ne, Mg, Si, and Fe) observed by the HEP-HI silicon detector telescope onboard the GEOTAIL satellite were investigated over the period from January 1993 to May 1996, from the viewpoint of solar modulation. From the GEOTAIL data and those of relativistic heavy particles observed by HEAO-3, the modulation potential φ was obtained by using a solution of the Fokker-Plank equation with the “force-field” approximation. In the equation the diffusion coefficient was used as adjustable parameter, under the assumptions of a fixed velocity of solar wind (400km/sec) and the radius of the heliosphere of 50AU. The time variation of the modulation potential thus obtained is compared with that obtained from the CLIMAX neutron monitor. A reasonable correlation between both time variations is found when five months delay is applied to the results obtained by the HEP-HI telescope.

We formed thin films of vanadylphthalocyanine (VOPc), vanadyldibenzophthalocyanine (VODBPc), and vanadylnaphthalocyanine (VONc) on sapphire substrates and measured their third-harmonic generation (THG) at 1.6 and 1.9 μm. The χ (3) values of amorphous and crystalline films were in the order VOPc>VODBPc>VONc. The third-order hyperpolarizabilities estimated at 1.6 μm from the χ (3) values of amorphous films were also in the same order.

The initial domain structure of GaAs films grown on several Si(001) surfaces is investigated using X-ray standing waves. GaAs/Si(001) samples, 4 ML thick, grown on three different Si substrates were used: an epitaxial Si surface (ESS), a mechanochemically polished surface (MCP), and a mechanochemically polished surface with plasma cleaning (plasma MCP). The domain ratio ambiguousness due to the film thickness is avoided by observing independent Bragg reflections of Si substrates. The results of X-ray standing wave measurement reveal that all GaAs films have double domain structures at the initial stage, even though final domain structures are single. The ratio of the two domains was almost 1 : 1 on the MCP surface, 6:4 on the ESS surface, and 4.5:5.5 on the plasma MCP surface. The dominant GaAs domains on the ESS and plasma MCP surfaces were the same as those obtained on thicker GaAs films. This suggests there is a rapid decrease in the GaAs domain during the early stages of growth on an ESS and plasma MCP surfaces.

Recently, space radiation dosimetry measurements were made by passive and active detectors inside the Spacelab [STS-47 (FMPT): 300km, 57°, STS-65 (IML-2 mission): 300km, 28.5°]. The LET distributions obtained by antioxidant doped CR-39 inside the Spacelab were compared with those measured by the tissue equivalent proportional counter (TEPC) and the real time radiation monitoring device (RRMD) consisting of eight silicon detectors. While both distributions by CR-39 are in good agreement with those obtained by active detectors over the region of LET of several tens to 200 keV/μm, a significant difference in the LET region of smaller than several tens keV/μm is seen. It is considered to be caused by the dip angle dependence of track formation sensitivity in CR-39. The track formation sensitivity for different dip angle were measured for several high heavy energy ions. Using these results, the correction for the dip angle was made for the LET distribution. The corrected result is consistent with the results obtained by active detectors.

The composition and energy spectra of anomalous cosmic-rays (ACRs) in the energies 6 – 200 MeV/n have been measured during the period from September 1992 to August 1995 using the High Energy Particle instrument onboard the GEOTAIL satellite orbiting at 1 AU. A remarkable enhancement of ACR N, O, Ne and Ar is observed during the period. A flux enhancement of anomalous argon at 1 AU is confirmed by the GEOTAIL satellite. The first possible evidence for the emergence of a measurable sulfur component in ACR below about 20 MeV/n is found. The flux increase of anomalous sulfur with 10.4 eV FIP is smaller than that of ACR carbon with 11.3 eV FIP, and much smaller than those of high FIP elements, which suggests that the fraction of neutral carbon and sulfur atoms is significantly lower in the very local interstellar medium.

Space radiation dosimetry measurements have been made on board the Space Shuttle STS-65 in the Second International Microgravity Laboratory (IML-2). In these measurements, three kinds of detectors were used; one is a newly developed active detector telescope called "Real-time Radiation Monitoring Device (RRMD)" utilizing silicon semi-conductor detectors and others are conventional detectors of thermoluminescence dosimeters (TLDs) and CR-39 plastic track detectors. Using the RRMD detector, the first attempt of real-time monitoring of space radiation has been achieved successfully for a continuous period of 251.3 h, giving the temporal variations of LET distribution, particle count rates, and rates of absorbed dose and dose equivalent. The RRMD results indicate that a clear enhancement of the number of trapped particles is seen at the South Atlantic Anomaly (SAA) without clear enhancement of dose equivalent, while some daily periodic enhancements of dose equivalent due to high LET particles are seen at the lower geomagnetic cutoff regions for galactic cosmic ray particles (GCRs). Therefore, the main contribution to dose equivalent is seen to be due to GCRs in this low altitude mission (300 km). Also, the dose equivalent rates obtained by TLDs and CR-39 ranged from 146.9 to 165.2 microSv/day and the average quality factors from 1.45 to 1.57 depending on the locations and directions of detectors inside the Space-lab at this highly protected orbit for space radiation with a small inclination (28.5 degrees) and a low altitude (300 km). The LET distributions obtained by two different detectors, RRMD and CR-39, are in good agreement in the region of 15-200 keV/mm and difference of these distributions in the regions of LET15 keV/mm and LET200 keV/mm can be explained by considering characteristics of CR-39 etched track formation especially for the low LET tracks.

Although methods of fabricating multilayers for soft x-ray mirrors have recently been developed, problems such as roughness and density errors still need serious consideration. The traditional way to characterize the properties of multilayer mirrors has been by small angle x-ray scattering, TEM, and optical methods. However, even with these techniques, the dependence of reflectivity on interface roughness and the desity of each layer has not been understood clearly, owing to the high sensitivity of reflectivity to several parameters.

The real time monitoring of environmental radiation in the Space-Lab of STS-65 (IML-2: inclination 28.5°, mitude 300 km) has been achieved successfully through the flight by a new silicon detector telescope called “Real time Radiation Monitoring Device” (RRMD). It consists of two 2-dimensional position sensitive silicon detectors and six diode type silicon detectors. In this monitoring, the temporal variation of rates of particle flux, together with the dose equivalent and the LET distribution at three locations in the Space-Lab, were reasonably given in real time. The LET distribution obtained by the RRMD and CR-39 track detectors measured at the same location is in good agreement except at the highest LET region >200 keV/μm and the lowest LET region

A new allene-doped liquid argon homogeneous calorimeter has been constructed for measurement of energies of relativistic heavy ions. Its electrode system consists of thin multi-parallel plates and it has been tested for relativistic Au ions from Bevalac at LBL. The results are compared with those obtained by simulation, including “quenching factor”, “positive ion effect” and “electron attachment to electronegative impurities”. The pattern shown in ΔE − E scatter plots, obtained from the multi-parallel plate electrode calorimeter, is in good agreement with those obtained by simulation, but the energy resolution for Au ions is three times or more worse than that of the simulation. At present the reason for the difference is not clear. By simulation, it is shown that the identification of adjacent charges or isotopes is possible for relativistic Na, Fe and La ions stopped in the calorimeter, using signals both from the cell in which ions stopped and from the preceding cell.

Single-wall (SW) tubes were produced by co-evaporation of carbon and lanthanum in helium gas and examined by transmission electron microscopy (TEM). TEM samples were collected directly from a space near the arc evaporation source during evaporation. SW tubes growing radially from compound particles were observed 4 cm above the source, but not 2 cm. The ‘sea urchin’-like morphology of these tubes were similar to those observed for soot deposited on the inner walls of the reaction chamber, suggesting that soot particles were formed first in the gas phase and SW tubes grew from them before deposition on the chamber wall. The temperature distribution and flow velocity of convection around the source are used for discussion of the growth mechanism of the SW tubes.

Using the LET distribution obtained by CR-39 plastic track detectors and the total absorbed dose obtained by TLDs, whose response for relativistic heavy ions is proportional to the absorbed dose, the dose equivalents at various locations inside the Space Shuttle (STS-47) have been estimated. The results show a large difference in the effective quality factor compared with the results obtained from a tissue equivalent proportional counter. The reason for this discrepancy is discussed.

Graphite tubules and polyhedral particles grown on an electrode surface of arc-discharge have been studied by electron microscopy. The observations of their structures and morphologies lead to a growth model in which ion bombardment and high electric field at the tip of a tubule play crucial roles for the tube growth.

Using 5-in.-diameter Si(Li) detectors with a detector thickness of 1, 2 and 3 mm combined with 62 mm × 62 mm position-sensitive Si detectors, an excellent isotope telescope has been constructed for the Geotail mission. The performance of the telescope and the individual detectors has been investigated using 56Fe beams with energies between 430 and 696 MeV/n. The nonuniformity of the detector thickness as measured by exposing the detectors to a monochromatic Fe beam is 0.44% for 1 mm thick detectors, 0.54% for 2 mm thick detectors and 0.15% for 3 mm thick detectors. The secondary isotopes of Al through Fe produced by 430 MeV/n 56Fe in a polyethylene target were clearly resolved by the telescope. The measured mass resolution for Si, Ca and Mn were 0.36 amu, 0.42 amu and 0.44 amu in FWHM, respectively. The telescope has the following two key features: an excellent resolution (better than 0.5 amu) and an exceptionally high sensitivity ( SΩ = 43 cm 2 sr ) for a broad range of species from He through Ni with energies between 2.4 and 210 MeV/n.

The crystal structure and the electronic structure of crystalline C 60 grown from a benzene solution have been studied by transmission electron microscopy and energy loss spectroscopy. Electron diffraction patterns and high-resolution images reveal an hcp structure ( a = 1.01±0.01 nm , c = 1.65±0.02 nm ) with stacking disorders. Electron energy loss spectra in a low-loss region revealed not only two collective excitations at 6.5 and 26 eV but also several single-electron excitations. From carbon K-shell excitation, spectral information on unoccupied π ∗ and σ ∗ bands has been obtained.

In order to investigate its mass resolution, a stack of sheets of the plastic CR-39 was exposed to a beam of 600 MeV n 56 Fe ions. From this exposure, a total of 74 iron events were analyzed. The mass resolution for 56 Fe was obtained as 0.34 ± 0.14 amu.

A “pure” liquid argon calorimeter has been constructed with the aim of approaching the ideal high energy resolution. The electrode system of the calorimeter consists of 192 G-10 plates of 1.2 mm thickness placed at intervals of 9mm. The sensitive volume of the calorimeter is 0.93 m2 × 2.0 m. An energy resolution of (2.4±0.2)% (m.m.s.) was achieved of these formulas is discussed. compared to the values predicted by Waseda's and Serpukhov's formulas. The validity of these formulas is discussed.

A new CR-39 plastic containing a small amount of antioxidants (Naugard-445) has been developed for use in a search for massive magnetic monopoles. Its characteristics have been investigated from the standpoint of the “heavy etching method”, which was proposed several years ago. The results are compared with those of pure CR-39 plastics measured under the same conditions.

A stack of the plastic CR-39 and nuclear emulsions was exposed at a vertical cut-off rigidity of 10.3 GV and an atmospheric depth of 7 g/cm2 for 30 h in May, 1979. Characteristics of shapes of etched cones produced by relativistic cosmic ray heavy nuclei in CR-39 are investigated and it is found that the surface ellipse of the etched track with large dip angle becomes more deformed. The detection threshold value is obtained to be Z/β ≅ 6 and the charge resolution (root mean square) to be ΔZ ≅ 0.4 charge units for relativistic iron nuclei in CR-39.

Characteristics of CR-39 plastic containing chlorinated compounds such as HCB and DCD have been studied using relativistic heavy ions from the LBL Bevalac. These results are compared with those of pure CR-39, focusing in particular on etching properties and on whether a penetrating etch hole is produced along each particle path by a long duration etch. The relation between the reduced track etch rate and the etchant concentration for CR-39 containing HCB is quite different from that of pure CR-39. Dilute etchants gives much higher track sensitivities than do more concentrated solutions in a wide range of REL. Since type HCB/DCD CR-39 loss its sensitivity in the interior of the bulk material for low REL produced by 2.1 GeV/ n Ne ions, penetrating etch holes are not produced along the particle paths after a heavy etching.

We have conducted an underground search for supermassive relic particles by an 80 m 2 array consisting of three layers of track detector CR-39. The non-observation of penetrating tracks places the velocity-dependent flux upper limits down to 2 × 10 −14 cm −2 s −1 sr −1 for various electrically or magnetically charged particles under assumptions on their energy losses in the low- velocity region. Assuming that the nuclear recoils are effective to the track formation of CR-39, this experiment sets the best flux limits for such relic particles in the velocity region 4 × 10 −5 β −4 .

A search for massive magnetic monopoles, predicted by the grand unified theories, has been performed using plastic nuclear track detectors (cellulose nitrate) with a total area of about 100 m 2 , which were exposed at ground level for 3.3 yr. The effective solid angle for detection of monopoles is estimated over the velocity range 0.03 c v c . An upper limit of 5.2 × 10 −15 cm −2 s −1 sr −1 at 90% CL is obtained for the flux of unit magnetic monopoles with velocities higher than 0.04 c .

We are setting up a large scale (1000 m2) monopole search experiment using a highly sensitive plastic track detector CR-39. By applying a heavy etching method, this detector will perform a background-free search for GUT monopoles down to a flux of 10-16 cm-2 sec-1 sr-1 in the velocity range 10-3 < β < 1. To realize such an experiment, we have made some effort for improving the sensitivity of CR-39 plastic and the uniformity of thickness, and for reducing the number of background holes. These results will be reported as well as our experimental plan.

The measurement of the registration-temperature effect on track response of CR-39 plastic has been made in vacuum over a wide temperature range. The result is almost the same as that of Thompson and co-workers (1982), which was obtained in dry-air environment. Also, it is found that the fractional change of track response for alpha-particles per unit registration temperature is smaller than that for higher LET particles.

A stack of CR-39 sheets has been exposed to 96 MeV/n and 2.1 GeV/n Ar beams in order to study uniformity of response and the response curve. Variation in response of the area of about 50 cm × 50 cm for one sheet was within 1.5 %. Roughness of the surface after 27 hr etching and the charge resolution were improved by changing temperature-time curing cycles. Steeper response curve at high REL region was observed and it was confirmed that our CR-39 has higher sensitivity in the recording of nuclear tracks down to Z/β ≃ 6 for vertical incidence.