排序方式: 共有12条查询结果,搜索用时 15 毫秒
1.
For ABO 4 type ternary oxides, high pressure phase transformations known up to the present are reviewed, and an attempt is made to explain and predict crystal structures of their high pressure phases. When ABO 4 type compounds are plotted based on the two variables, k=r A /r B and t=(r A +r B )/2r O, where r A , r B , and r O are the ionic radii of A and B cations and divalent oxygen, they can be classified into the major structure types. It is found empirically that a compound basically transforms to the structure type isostructural with a compound lying in a classified area with the same k and larger t values in the diagram. 相似文献
2.
Philip Lah Jayaram N. Chengalur Frank H. Briggs Matthew Colless Roberto De Propris Michael B. Pracy W. J. G. de Blok Shinobu S. Fujita Masaru Ajiki Yasuhiro Shioya Tohru Nagao Takashi Murayama Yoshiaki Taniguchi Masafumi Yagi Sadanori Okamura 《Monthly notices of the Royal Astronomical Society》2007,376(3):1357-1366
3.
Tsutsumi S Yamaguchi Y Nishida I Akiyama K Zakaria MP Takada H 《Marine pollution bulletin》2002,45(1-12):325-331
Alkylbenzenes, molecular markers of sewage, were measured in 34 green mussels collected from India, Indonesia, Malaysia, Thailand, Cambodia, Vietnam, and the Philippines together with blue mussels collected from Tokyo Bay, Japan. Linear alkylbenzene (LAB) concentrations in South and South East Asian countries ranged from 10 to 1640 ng-∑LAB/g-dry tissue. In some populous cities, LAB concentrations were similar or higher than those found in northern Tokyo Bay which is heavily impacted by sewage effluents. I/E ratios (a ratio of internal to external isomers of LABs) in the South and South East Asian countries (1–3) were much lower than those in Tokyo Bay (3–8), indicating sewage discharged in the coastal zone is poorly treated (e.g., raw sewage and/or primary effluents). Alkylbenzenes with branched alkyl chains, tetrapropylene-based alkylbenzenes, were also detected in mussels from Indonesia and Philippines. This “tell-tale” sign indicates that poorly degradable detergents are still in use in this area, although they have long been phased-out in many industrialized countries. 相似文献
4.
Yuto Kurumada Shogo Aoki Kazumasa Aoki Daichi Kato Mototaka Saneyoshi Khishigjav Tsogtbaatar Brian F. Windley Shinobu Ishigaki 《地学学报》2020,32(4):246-252
To verify the usefulness of calcite U–Pb measurement for vertebrate‐bearing strata in the Eastern Gobi, Mongolia, we performed laser ablation‐inductively coupled plasma‐mass spectrometry calcite U–Pb and trace element analyses of three caliche (calcrete) of the Bayn Shire Formation. The trace element analysis demonstrates high concentration of U in the calcites. Two meaningful calcite U–Pb ages were obtained; 95.9 ± 6.0 and 89.6 ± 4.0 Ma, which are consistent with published ages from the Bayn Shire Formation. Our results demonstrate that the calcite U–Pb method can be powerful tool for age determination of vertebrate‐bearing strata in the Gobi that do not contain index fossils or beds, but do contain caliches. This would make it possible for a comparison of biostratigraphy between the Gobi and other areas yielding abundant vertebrate fossils in Asia, North America and Europe, based on chronological data. 相似文献
5.
Distribution of plant species and species-soil relationship in the east central Gurbantunggut Desert,China 总被引:1,自引:0,他引:1
AN Ping LI Xiangjun ZHENG Yuanrun ENEJI A. Egrinya QIMAN Yunus ZHENG Mingqing INANAGA Shinobu 《地理学报》2015,25(1):101-112
The distribution of plant species and relationships between species and soil factors in the east central part of Gurbantunggut Desert was studied to provide more insight into the flora and determine differences in vegetation across various parts of the desert. Two-way Cluster Analysis showed that the vegetation in the area could be divided into three groups, the first group was dominated by the shrub species, Ephedra przewalskii and the grass species, Carex physodes mainly in areas of flat grounds and gentle slopes; the second group was dominated by C. physodes, Artemisia songorica and A. xerophytica mainly on the slope of sand dunes and the third group was dominated by the shrub species, Haloxylon persicum mainly on the top of sand dunes. There was no difference in plant density between Groups 1 and 2 but there was a significant decrease in Group 3. Soil water under vegetation Group 3 was much lower than that in the other two groups at all soil depths. The EC, organic matter, total P and soluble Na, Ca and Mg varied very similarly with soil water. Canonical correspondence analysis (CCA) satisfactorily assessed the species-soil relations in the area. The distribution of plant species was strongly correlated with the soil factors of water content, organic matter, EC and nutrients. The variations in species occurrence explained by the three CCA axes were about 70%, indicating that some explanatory site variables may exist outside our studied parameters. Soil texture is suggested to be included in future studies to improve the explanation of CCA. 相似文献
6.
We present earth rotation results from the ultra-rapid operations during the continuous VLBI campaigns CONT11 and CONT14. The baseline Onsala–Tsukuba, i.e., using two out of the 13 and 17 stations contributing to CONT11 and CONT14, respectively, was used to derive UT1-UTC in ultra-rapid mode during the ongoing campaigns. The latency between a new observation and a new UT1-UTC result was less than 10 min for more than 95% of the observations. The accuracy of the derived ultra-rapid UT1-UTC results is approximately a factor of three worse than results from optimized one-baseline sessions and/or complete analysis of large VLBI networks. This is, however, due to that the one-baseline picked from the CONT campaigns is not optimized for earth rotation determination. Our results prove that the 24/7 operation mode planned for VGOS, the next-generation VLBI system, is possible already today. However, further improvements in data connectivity of stations and correlators as well in the automated analysis are necessary to realize the ambitious VGOS plans. 相似文献
7.
Kurtulus Atasever Shogo Inanaga Toru Takeuchi Yuki Terazawa Oguz C. Celik 《地震工程与结构动力学》2020,49(15):1640-1661
There has been an increasing interest in using residual deformation as a seismic performance indicator for earthquake resistant building design. Self-centering braced structural systems are viable candidates for minimizing residual deformations following a major earthquake. Hence, this study proposes an alternative type of buckling restrained brace (BRB) with externally attached posttensioned (PT-BRB) carbon fiber composite cables (CFCCs). The steel core of the brace is used as an energy dissipator, whereas the CFCCs provide the self-centering force for minimizing residual story drifts. Three proof-of-concept specimens are designed, fabricated, and cyclically tested at different posttensioning force levels. The CFCC behavior to obtain cyclic response, including the anchorage system, is examined closely. A parametric study is also conducted to show the effect of the different configurations of PT-BRBs on the inelastic response. Furthermore, optimal brace parameters are discussed to realize design recommendations. The results indicated that the implementation of partially self-centering BRBs in building frames can lead to the target residual displacements. A stable behavior is obtained for the proposed PT-BRBs when subjected to the loading protocol specified in the American Institute of Steel Construction (AISC) 2016 Seismic Provisions. 相似文献
8.
XIONGYan KanakoMuramatsu MasahiroHirata KazatoOishi IchirowKaihotsu TamioTakamura ShinobuFurumi NoboruFujiwara 《地球空间信息科学学报》2004,7(2):117-122
We plan to estimate global net primary production (NPP) of vegetation using the Advanced Earth Observing Satellite-Ⅱ (ADEOS-Ⅱ) Global Imager (GLI) multi-spectral data. We derive an NPP estimation algorithm from ground measurement data on temperate plants in Japan. By the algorithm, we estimate NPP using a vegetation index based on pattern decomposition (VIPD) for the Mongolian Plateau. The VIPD is derived from Landsat ETM multi-spectral data, and the resulting NPP estimation is compared with ground data measured in a semi-arid area of Mongolia. The NPP estimation derived from satellite remote sensing data agrees with the ground measurement data within the error range of 15% when all above-ground vegetation NPP is calculated for different vegetation classifications. 相似文献
9.
Hassan M. Fadul Ahmed A. Salih Imad-eldin A. Ali Shinobu Inanaga 《International Journal of Applied Earth Observation and Geoinformation》1999,1(3-4)
The problems and impact of gully erosion along the Atbara River (Sudan), situated in semi-arid and arid environments, were investigated. The total gross area of gullied land and the loss of arable land by gully erosion were estimated. Multi-date sets of panchromatic aerial photographs and Landsat images (TM) were selected to represent two sites in the arid (New Halfa) and semi-arid (Showak town) zones along the Atbara River. Photo interpretation was conducted using physiographic and element methods. The interpretations detected the effects of water action in different climatic zones on geology, lithology, vegetation and land use. The results showed that the traditional rainfed agriculture has accelerated gully erosion in the semi-arid rather than in the arid zone. The progressive rate of gully erosion in the semi-arid zone resulted in loss of arable land at about 13.4 km2 yr-1 and 9.8 km2 yr-1 in the periods 1985–1987 and 1987–1990, respectively. The study provided data on the monitoring and mapping of gully erosion along the Atbara River and its tributaries. 相似文献
10.