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161.
162.
A landfill disposal site can be described as “an artificial vessel” and must satisfy the following three demands (1) storage and disposal of waste; (2) protection of the environment; and (3) benefit for nearby residents by taking advantage of consequential effects. The concept of risk was effectively considered to emphasize the importance of monitoring systems in landfill disposal sites, especially to protect the environment. Because a part of the R&D was involved in creating a monitoring system for a landfill disposal site, the present development and future potential of a system which can detect the leakage of watershield sheets, was discussed. 相似文献
163.
164.
This letter presents the possibility of detecting earthquakes (EQs) from microwaves emitted when rock fractures. The method is based on an experiment in which microwave emission was detected from rock fracturing in a laboratory for the first time in the world. First, the method of calibrating emitted microwave power from experimental data is presented. A model of microwave emission and propagation to a satellite is then proposed. An advantage of microwaves is that they penetrate the Earth's ionosphere, unlike radiowaves of frequencies lower than several tens of megahertz. The power received by a satelliteborne receiver is estimated by assuming parameters of a radiometer currently operating in orbit. The result indicates that a satelliteborne receiver can detect microwave signals generated by an EQ. Based on this result, we attempted to detect some features associated with an actual EQ from the data of the Advanced Microwave Scanning Radiometer for Earth Observation System aboard the remote sensing satellite Aqua. 相似文献
165.
Duplex of metamorphic units including ultramafic rocks in the central region of Tokunoshima,Southwest Japan 下载免费PDF全文
Geological observations in the central part of Tokunoshima in the Amami Islands, Southwest Japan, reveal that discrete layers of serpentinite, dioritic gneiss, and amphibolite are intercalated into pelitic schist and these rock bodies form a northwest‐dipping tectonic stack. A subhorizontal psammitic schist layer overlies them. These rocks underwent ductile deformation that is denoted by penetrative foliation and mineral lineation. Microstructures of the sheared metamorphic rocks and serpentinite indicate top‐to‐the‐east, ‐southeast or ‐south (hanging‐wall up) displacements. The en echelon array of rock bodies is interpreted as a duplex with the psammitic schist layer on its top and the pelitic schist layer on its bottom. It is inferred that the serpentinite‐bearing duplex was formed due to the tectonic erosion and the subsequent accretionary growth operated in a Cretaceous or older subduction zone. Tokunoshima has been considered to belong to the Shimanto Belt. However, regional low‐pressure and high‐temperature type amphibolite‐facies metamorphism and related ductile deformation have not been recognized in the other areas of the Shimanto Belt. There is no metamorphic rock occurrence comparable to that of Tokunoshima in the neighboring islands. The metamorphic rocks in Tokunoshima can be correlated to any of low‐pressure/temperature type metamorphic regions in Kyushu. 相似文献
166.
Elastomeric isolation bearings consist of multiple rubber layers with their top and bottom surfaces bonded to steel plates to restrict compressive deformation. Deformation constraints result in a variation of elastic modulus over the cross section of the rubber layers. In this paper, we describe a normalized compression modulus distribution on a circular rubber pad. The compressive and bending moduli of the rubber pad can be reproduced by applying the distribution to a series of axial springs. We also present a mechanical model for predicting the behavior of elastomeric seismic isolation bearings subject to large shear deformation and high compressive load. The mechanical model consists of a series of multiple shear springs at midheight and a series of axial springs at the top and bottom interfaces of the bearing. Simulation analyses of bearing tests were conducted to validate the proposed model. The analyses demonstrated that a model for circular lead-rubber bearings can successfully capture the influence of the axial load magnitude on the bearing shear behavior. The new model can simulate much more realistic behavior than prior models based on a uniform modulus assumption. 相似文献
167.
Yuri D. Zakharov Nataliya G. Boriskina Alexander V. Ignatyev Kazushige Tanabe Yasunari Shigeta Alexander M. Popov Tamara B. Afanasyeva Haruyoshi Maeda 《Cretaceous Research》1999,20(6):685
In the northwestern circum-Pacific, two main trends in Late Cretaceous temperatures can be recognized. (1) In general, a recurrent warming trend is thought to have begun in the Turonian–Campanian, reaching temperature maxima in the early Late Santonian and early Late Campanian, and temperature minima in the earliest Santonian and perhaps early Campanian. (2) During the Maastrichtian, temperatures dropped sharply, with only a slight warming in the early Late Maastrichtian. The existence of a thermal maximum at the Coniacian–Santonian transition has previously been expected, but is not confirmed by new isotopic results. 相似文献
168.
169.
Surface electronic structures of metal oxides such as MgO, TiO2, SrTiO3, ReO3 and transition-metal monoxides are discussed based on the first-principles DV-Xα cluster and slab methods. Particular attention is paid to the origin and properties of intrinsic and extrinsic surface states. A close correlation between the surface structure and electronic states is confirmed. Some exotic properties of polar oxide surfaces, for example the formation of a two-dimensional metallic band, are predicted. 相似文献
170.
Alexander Chakhmakhchev Masaru Suzuki Amane Waseda Kuniaki Takayama 《Organic Geochemistry》1997,27(7-8)
Siliceous sourced Tertiary oils from the Circum-Pacific area of Japan, Russia and the U.S.A. have a heavy carbon isotope composition, monomodal n-alkane distributions, and nearly identical regular sterane compositions with a predominance of C27 homologues. These are consistent with open marine depositional environments dominated by diatomaceous organic matter. However, a number of alkane and biomarker parameters such as Pr/Ph, CPI, relative concentration of 28,30-bisnorhopane, and the C35/C34 homohopane ratio indicate more oxic depositional environments for the source rocks of Japan and Russia. In contrast to the California Monterey Formation sourced oils, petroleums with low maturity levels from the North Sakhalin basin, Russia and the Akita basin, Japan have lower concentrations of asphaltenes and sulphur and are characterized by higher API gravities. A correlation of extractable organic matter from source rocks vs the least matured petroleums demonstrates that oil expulsion in siliceous shales of the Akita basin occurs at a maturity level corresponding to Ro≥0.65%, which is in the range of the conventional oil window (Ro = 0.6−1.1%). 相似文献