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1.
In this study, households’ decisions on reconstruction of damaged houses were modeled, using questionnaire data in Japan. Characteristics of households’ decisions were investigated using parameter estimation results. The effects of subsidizing policy were evaluated as follows. First, subsidy for rebuilding may be effective for the households whose houses were heavily damaged. Second, there is a possibility that subsidy accelerated rebuilding of houses by the households having children. Third, subsidy for rebuilding may not be effective for elderly people’s households and households in depopulated areas.  相似文献   
2.
 The Middle Miocene Tobe hornfels in the Sanbagawa metamorphic belt, western Shikoku, southwest Japan, is characterized by an abnormally steep metamorphic gradient compared with other hornfelses associated with intrusive bodies. The basic hornfels, originally Sanbagawa greenschist rocks, is divided into the following three metamorphic zones: plagioclase, hornblende, and orthopyroxene. The plagioclase zone is defined by the appearance of calcic plagioclase, the hornblende zone by the assemblage of hornblende+calcic plagioclase+quartz, and the orthopyroxene zone is characterized by the assemblage of orthopyroxene + clinopyroxene + plagioclase + quartz. Calcic amphibole compositions change from actinolite to hornblende as a result of the continuous reactions during prograde metamorphism. Petrographical and thermometric studies indicate a metamorphic temperature range of 300–475°C for the plagioclase zone, 475–680°C for the hornblende zone, and 680–730°C for the orthopyroxene zone. The temperature gradient based on petrological studies is approximately 5°C/m, which is unusually high. Geological and petrological studies demonstrate that the hornfelses were formed by the focusing of high-temperature fluids through zones of relatively high fracture permeability. The steep thermal gradient in the Tobe hornfels body is consistent with a large fluid flux, greater than 8.3 × 10–7 m3 m–2S–1, over the relatively short duration of metamorphism, approximately 100 years. Received: 10 October 1995 / Accepted: 28 May 1996  相似文献   
3.
In association with the large solar flare of April 15, 2001, the Chacaltaya neutron monitor observed a 3.6σ enhancement of the counting rate between 13:51 and 14:15 UT. Since the enhancement was observed beginning 11 min before the GLE, solar neutrons must be involved in this enhancement. The integral energy spectrum of solar neutrons can be expressed by a simple power law in energy with the index γ=-3.0±1.0. On the other hand, an integral energy spectrum of solar protons has been obtained in the energy range between 650 MeV and 12 GeV. The spectrum can also be expressed by a power law with the power index γ=-2.75±0.15. The flux of solar protons observed at Chacaltaya (at 12 GeV) was already one order less than the flux of the galactic cosmic rays. It may be the first simultaneous observation of the energy spectra of both high-energy protons and neutrons. Comparing the Yohkoh soft X-ray telescope images with the observed particle time profiles, an interesting picture of the particle acceleration mechanism has been deduced.  相似文献   
4.
Pyrite framboid in sedimentary rocks could be concerned with arsenic contamination in groundwater of acidic environment and has been studied for the formation process of its unique morphology. However, not much has been discussed about the formation process based on the heavy-metal distribution in pyrite framboids and their aggregates. To reveal the formation process of pyrite framboids and their aggregates, mudstone from the Late Cretaceous Hakobuchi Group, central Hokkaido, Japan, are investigated for mode, petrographical, mineralogical, and micro-PIXE (particle-induced X-ray emission) analysis in this study. Spherical and sub-spherical pyrite framboids observed in polyframboids can be divided into two types based on the diameter of framboids (D) and the average diameter of microcrystals (d) within framboids: type 1, ranging from 2 to 9 μm and from 0.4 to 0.9 μm, respectively, and type 2, ranging from 8 to 50 μm and from 0.5 to 1.8 μm, respectively. Based on the quantitative traverse analyses and 2-D elemental mapping results by micro-PIXE, heterogeneities in the concentrations of heavy metals within the analyzed aggregations of pyrite are exhibited. On the basis of the As and Pb zoning patterns, the time range and chronological stages of pyrite-aggregation growth are revealed.  相似文献   
5.
Phytoremediation, a plant‐based and cost‐effective technology for the cleanup of contaminated soil and water, is receiving increasing attention. In this study, the aquatic macrophyte Eleocharis acicularis was examined for its ability to take up multiple heavy metals and its potential application for phytoremediation at an abandoned mining area in Hokkaido, Japan. Elemental concentrations were measured in samples of E. acicularis, water, and soil collected from areas of mine tailing and drainage. The results reveal that Pb, Fe, Cr, Cu, Ni, and Mn accumulation in the plants increased over the course of the experiment, exceeding their initial concentrations by factors of 930, 430, 60, 25, 10, and 6, respectively. The highest concentrations of Fe, Pb, Zn, Mn, Cr, Cu, and Ni within the plants were 59500, 1120, 964, 388, 265, 235, and 47.4 mg/kg dry wt., respectively, for plants growing in mine drainage after 11 months of the experiment. These results indicate that E. acicularis is a hyperaccumulator of Pb. We also found high Si concentrations in E. acicularis (2.08%). It is likely that heavy metals exist in opal‐A within cells of the plant. The bioconcentration factors (BCF: ratio of metal concentration in the plant shoots to that in the soil) obtained for Cr, Cu, Zn, Ni, Mn, and Pb were 3.27, 1.65, 1.29, 1.26, 1.11, and 0.82, respectively. The existence of heavy metals as sulphides is thought to have restricted the metal‐uptake efficiency of E. acicularis at the mine site. The results of this study indicate that E. acicularis shows great potential in the phytoremediation of mine tailing and drainage rich in heavy metals.  相似文献   
6.
Ship berthing and mooring monitoring system by using pneumatic-type fenders has been proposed. This system consists of present berth monitoring system including a mooring line load monitoring system, and a fender load monitoring system. The fender loads such as fender deflection and reaction force are calculated by measuring inner air pressure of the pneumatic fenders, which have unique characteristics in performance. Furthermore both loads for the mooring lines and the fenders can be used to estimate moored ship motions simultaneously. Total ship monitoring system at jetty can be achieved and contributes safe ship berthing and mooring.  相似文献   
7.
Temperature dependencies of magnetic rotation were measured in micron-sized silicates dispersed in ethanol for two different samples of kaolinite. Magnetic rotation proceeded by balance between thermal agitation energy and magnetic anisotropy energy. Measurements were performed between 195 and 343 K. The field intensity required to achieve magnetic alignment of microcrystals increases with temperature, because of the temperature dependence of paramagnetic anisotropy, and the temperature dependence of thermal agitation energy. The results indicate that the values of magnetic anisotropy of nonmagnetic materials might partially derive from the paramagnetic moments, which derive from paramagnetic impurity ions. The present experiment provides a technical basis for determining the precise values of diamagnetic anisotropy ()DIA from minerals which have a concentration of paramagnetic ions and do not form a single crystal large enough to allow bulk measurements. The values of ()DIA can be obtained by extrapolating the –T relations, which follow the Curie law, to the temperature limits.  相似文献   
8.
Phytoremediation is an environmental remediation technique that takes advantage of plant physiology and metabolism. The unique property of heavy metal hyperaccumulation by the macrophyte Eleocharis acicularis is of great significance in the phytoremediation of water and sediments contaminated by heavy metals at mine sites. In this study, a field cultivation experiment was performed to examine the applicability of E. acicularis to the remediation of water contaminated by heavy metals. The highest concentrations of heavy metals in the shoots of E. acicularis were 20 200 mg Cu/kg, 14 200 mg Zn/kg, 1740 mg As/kg, 894 mg Pb/kg, and 239 mg Cd/kg. The concentrations of Cu, Zn, As, Cd, and Pb in the shoots correlate with their concentrations in the soil in a log‐linear fashion. The bioconcentration factor for these elements decreases log‐linearly with increasing concentration in the soil. The results indicate the ability of E. acicularis to hyperaccumulate Cu, Zn, As, and Cd under natural conditions, making it a good candidate species for the phytoremediation of water contaminated by heavy metals.  相似文献   
9.
Abstract A deep section of accretionary complex, the metamorphosed Susunai Complex, is observed on Sakhalin Is., Russia. High pressure part of pumpellyite-actinolite facies metavolcanics, metacherts and metapelites are well exposed and constitute a tectonic pile preserving primary structures related to underplating of the oceanic crust. Three stages of deformation, D1 through D3, suggest successive deformation during subduction, underplating and exhumation of the complex. Oceanic material in the complex is more abundant than other well documented ancient accretionary complexes (e.g. the Shimanto Belt in southwest Japan and the Ghost Rocks Formation in Alaska), which were shallowly underplated. At Susunai, deep down-stepping of a décollément has scraped off the upper part of the oceanic crust, primarily the pillowed basalt horizon. This down-stepping results from crustal weakening as overpressured water is released from the fractured oceanic crust during metamorphism.  相似文献   
10.
Summary Fe and Mn distribution in the pumpellyite group minerals (W 8 X 4 Y 8 Z 12056-n (OH) n ) has been studied by using57Fe Mössbauer spectroscopy. The studied Fe-pumpellyites, belonging to the pumpellyite-julgoldite series, were collected from two localities; metabasites in the Tokoro belt, Hokkaido, and gabbroic sills in the Shimane Peninsula, Japan. Okhotskite, an Mn3+-dominant pumpellyite group mineral, was separated from the ores of metamorphosed manganiferous iron ore deposits in the Tokoro belt.57Fe Mössbauer spectrum of Tokoro Fe-pumpellyite is composed of two Fe2+- and two Fe3+-doublets. On the basis of the single crystal structure refinements of Al-pumpellyites published so far, doublets were assigned to Fe W 2+ (IS= 1.01 andQS = 2.73 mm/s), Fe X 2+ (IS = 0.97 andQS = 3.18 mm/s), Fe X 3+ (IS = 0.29 andQS =1.37 mm/s) and Fe Y 3+ (IS = 0.36 andQS = 2.09 mm/s), whereIS is isomer shift relative to a metallic iron absorber andQS is quadrupole splitting. The Mössbauer spectrum of the Mitsu Fepumpellyite is composed of three doublets assigned to Fe X 2+ (IS= 1.14 andQS = 3.20 mm/s), Fe X 3+ (IS = 0.36 andQS =1.13 mm/s) and Fe Y 3+ (IS = 0.37 andQS= 1.93 mm/s). These assignments show strong preference of Fe3+ in the X-site. The Mössbauer spectrum of the okhotskite is composed of two doublets by Fe X 3+ (IS= 0.37 andQS = 1.13 mm/s) and Fe Y 3+ (IS = 0.42 andQS = 2.18 mm/s). The area ratio shows that Fe X 3+ :Fe Y 3+ ratio is 94:6. On the basis of chemical and Mössbauer analyses, Mn X 3+ :Mn Y 3+ ratio is given as 19:81, indicating stronger Y-site preference of Mn3+ than Fe3+, what is consistent with Jahn-Teller theory. Al, Mn3+ and Fe3+ prefer the Y-site in this order.
Eine57Fe Mössbauer-Studie von Mineralen der Pumpellyit-Okhotskit-Julgoldit-Serie
Zusammenfassung Die Fe- und Mn-Verteilung in Mineralen der Pumpellyit-Gruppe (W 8 X 4 Y 8 Z 12O56-n (OH)n) wurde mittels Mössbauer-Spektroskopie studiert. Die untersuchten Fe-Pumpellyite der Pumpellyit-Julgoldit-Serie stammen von zwei verschiedenen japanischen Lokalitäten: von Metabasiten des Tokoro-Gürtels, Hokkaido, und von Gabbro-Sills der Shimane Halbinsel. Okhotskit, ein Mn3+-dominiertes Mineral der Pumpellyit-Gruppe, wurde aus Erzen einer Mn-führenden Eisenerzlagerstätte des Tokoro-Gürtels separiert. Das57Fe Mössbauer-Spektrum der Tokoro Fe-Pumpellyite zeigt zwei Fe2+- und zwei Fe3+-Doubletten. Auf Grund bisher publizierter verfeinerter Einkristall-Strukturuntersuchungen von Al-Pumpellyiten werden diese Doubletten folgendermaßen zugeordnet: Fe W 2+ (IS = 1.01 undQS = 2.73 mm/s), Fe X 2+ (IS = 0.97 undQS = 3.18 mm/s), Fe X 3+ (IS = 0.29 undQS =1.37 mm/s) und Fe Y 3+ (IS = 0.36 undQS = 2.09 mm/s).IS bezeichnet dabei die Isomer-Shift relativ zu einem metallischen Eisenabsorbenten,QS das Quadrupole-Splitting. Diese Zuordnungen belegen den bevorzugten Einbau von Fe3+ in die X-Position. Das Mössbauer-Spektrum von Okhotskit zeigt zwei Doubletten bei Fe X 3+ (IS = 0.37 undQS = 1.13 mm/s) und Fe Y 3+ (IS = 0.42 undQS = 2.18 mm/s). Das Flächenverhältnis zeigt, daß das Verhältnis Fe X 3+ :Fe Y 3+ 94:6 ist. Auf Grund der chemischen und der Mössbauer-Analysen wird das Mn X 3+ :Mn Y 3+ Verhältnis mit 19:81 angegeben. Mn3+ zeigt somit eine stärkere Präferenz für die Y-Position als Fe3+, ein Resultat, das mit der Jahn-Teller-Theorie konsistent ist. Der bevorzugte Einbau in die Y-Position ist, in dieser Reihenfolge, Al>Mn3+>Fe3+.


With 4 Figures  相似文献   
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