Surface energy partitioning and evapotranspiration over a double‐cropping paddy field in Bangladesh     

Md. Shahadat Hossen  Masayoshi Mano  Akira Miyata  Md. Abdul Baten  Tetsuya Hiyama 《水文研究》2012,26(9):1311-1320

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Light scattering calculations by the Fredholm integral equation method     

Masafumi Matsumura  Munezo Seki 《Astrophysics and Space Science》1991,176(2):283-295

The Fredholm integral equation method (FIM), originally introduced by Holtet al. to solve the light scattering problem for ellipsoidal particles, is reinvestigated by taking into account a recent great progress in numerical computers. A numerical code optimized for vector-processing computers is developed, and is applied to the light scattering by spherical and spheroidal particles. The results for these particles are compared with those by the Mie theory and by Asano and Yamamoto, respectively, and it is confirmed that the agreement with both of them is satisfactory. Sample calculations are also performed for the oblique incidence, in which the direction of incidence is not parallel nor perpendicular to the symmetry axis of the particle. No difficulties in the computation are found compared with the calculations for the parallel or perpendicular incidence. We study the efficiency factor for polarization (Q _pol) in general direction of incidence for spheroidal particles, and discuss the deviation from the Rayleigh approximation.  相似文献   

A simple fractionation method for determination of phosphorus components in phytoplankton: Application to natural populations of phytoplankton in summer surface waters of Tokyo Bay   总被引：1，自引：0，他引：1  

Kazuyasu Miyata  Akihiko Hattori 《Journal of Oceanography》1986,42(4):255-265

A simple procedure for fractionation of phosphorus components in natural populations of phytoplankton has been developed. By a combination of a trichloroacetic acid (TCA) extraction, a hot dilute acid treatment, a charcoal treatment and an organic solvent extraction, cellular phosphorus was divided into orthophosphate, nucleotide phosphorus, sugar phosphates, acid-soluble polyphosphates, lipid phosphorus, nucleic acid phosphorus, acid-insoluble polyphosphates, and residual phosphorus. The recovery of phosphorus was 94±5%. This technique was applied to natural populations of phytoplankton in summer surface waters of Tokyo Bay. Nucleic acid phosphorus and orthophosphate were most abundant, and accounted for 30 to 50% of total phytoplankton phosphorus. The nucleic acid phosphorus was proportional to the biomass of phytoplankton, irrespective of ambient nutrient concentrations. The orthophosphate showed the largest change in association with the change in cellular phosphorus content as well as in ambient phosphate. The orthophosphate serves as a phosphorus reserve in the natural populations of phytoplankton in summer surface waters of Tokyo Bay whereSkeletonema costatum was dominant. Acid-insoluble polyphosphates tended to increase when ambient concentration of phosphate was high, but their amounts were almost one order of magnitude lower than that of orthophosphate.  相似文献   

Phylogeny of transfer RNA and origins of organelles     

Masami Hasegawa  Taka-Aki Yano  Takashi Miyata 《Precambrian Research》1981,14(1):81-98

By using nucleotide sequences of transfer RNA's, the endosymbiotic model for the origin of chloroplasts and mitochondria is examined. The endosymbiotic origin of the chloroplasts is confirmed, but concerning the origin of the mitochondria no conclusion can be drawn. Phyletic relations of euglenoids to higher plants and to animals are also discussed. Finally, phylogeny of fungi is discussed in terms of tRNA sequences and it is proposed that the classical taxonomy of fungi should be reconsidered in terms of molecular taxonomy or molecular paleontology.  相似文献   

New <Superscript>40</Superscript>Ar/<Superscript>39</Superscript>Ar age constraints on cooling and unroofing history of the metamorphic host rocks (and igneous intrusion associates) from the Bulfat Complex (Bulfat area), NE-Iraq     

Nihad M. Karo  Roland Oberhänsli  Ahmed M. Aqrawi  Elias M. Elias  Khalid J. Aswad  Masafumi Sudo 《Arabian Journal of Geosciences》2018,11(10):234

The Northern Zagros Suture Zone (NZSZ), formed as a result of the collision between Arabian and Sanandaj-Sirjan microplate, is considered as part of the Zagros orogenic belt. NZSZ is marked by two allochthonous thrust sheets in upward stacking order: lower and upper allochthon. The Bulfat complex is a part of the upper allochthon or “Ophiolite-bearing terrane” of Albian-Cenomenion age (97–105 Ma). Voluminous highly sheared serpentinites associated with ophiolites occur within this upper allochthon. In addition, the Gemo-Qandil Group is characterized by gabbroic to dioritic Bulfat intrusion with a crystallization age spanning from ~45 to ~?40 Ma, as well as extensive metapelites with contact to the Walash-Naupurdam metavolcanic rocks. Due to the deformation in the Sanandaj-Sirjan Zone along the eastern side of the Iraqi segment of NZSZ, the Gemo-Qandil Group was regionally metamorphosed during late Cretaceous (~?80 Ma). This tectono-compressional dynamics ultimately caused an oscillatory deformation against Arabian continental margin deposits as well. During these events, gabbro-diorite intrusion with high-grade contact metamorphic aureoles occurred near Bulfat. Thus, there is an overlap between regional and contact metamorphic conditions in the area. The earlier metamorphic characteristic can be seen only in places where the latter contact influence was insignificant. Generally, this can only observed at a distance of more than 2.5 km from the contact. According to petrographic details and field observations, the thermally metamorphosed metapelitic units of the metasediment have been completely assimilated, with only some streaks of biotite and relicts of initial foliation. They strongly resemble amphibolite-grade slices from the regional metamorphic rocks in the region. Metapelitic samples far from the intrusion give similar biotite cooling ages as the intrusive rocks. Thus, they may be affected by the same thermal event. ⁴⁰Ar/³⁹Ar dating of biotite in metapelite rocks of Bulfat by step-wise heating with laser gave average weighted isotopic ages of 34.78?±?0.06 Ma. This is interpreted as crystallization/recrystallization age of biotite possibly representing the time of cooling and uplift history of the Bulfat intrusion. Cooling and exhumation rates for the Bulfat gabbro-diorite rocks were estimated as ~?400 °C/Ma and ~?3.3 mm/year respectively. According to petrographic details, field observations and Ar/Ar dating concerning the contact metamorphism near Bulfat due to the gabbro-diorite intrusion, no significant deformation is visible during exhumation processes after the Paleogene tectono-thermal event, indicating that isotopic ages of 34.78?±?0.06 Ma could mark the timing of termination of the island arc activity in the Ophiolite-bearing terrane (upper allochthon).  相似文献   

Salinity in Soils and Tsunami Deposits in Areas Affected by the 2010 Chile and 2011 Japan Tsunamis   总被引：1，自引：0，他引：1  

Takumi Yoshii  Masahiro Imamura  Masafumi Matsuyama  Syunichi Koshimura  Masashi Matsuoka  Erick Mas  Cesar Jimenez 《Pure and Applied Geophysics》2013,170(6-8):1047-1066

The accumulation of data sets of past tsunamis is the most basic but reliable way to prepare for future tsunamis because the frequency of tsunami occurrence and their magnitude can be estimated by historical records of tsunamis. Investigation of tsunami deposits preserved in geological layers is an effective measure to understand ancient tsunamis that occurred before historical records began. However, the areas containing tsunami deposits can be narrower than the area of tsunami inundation, thus resulting in underestimation of the magnitude of past tsunamis. A field survey was conducted after the 2010 Chile tsunami and 2011 Japan tsunami to investigate the chemical properties of the tsunami-inundated soil to examine the applicability of tsunami inundation surveys considering water-soluble salts in soil. The soil and tsunami deposits collected in the tsunami-inundated areas are rich in water-soluble ions (Na⁺, Mg²⁺, Cl^?, Br^? and SO ₄ ^2? ) compared with the samples collected in the non-inundated areas. The analytical result that the ratios of Na⁺, Mg²⁺, Br^? and SO ₄ ^2? to Cl^? are nearly the same in the tsunami deposits and in the tsunami-inundated soil suggests that the deposition of these ions resulting from the tsunami inundation does not depend on whether or not tsunami deposits exist. Discriminant analysis of the tsunami-inundated areas using the ion contents shows the high applicability of these ions to the detection of tsunami inundation during periods when the amount of rainfall is limited. To examine the applicability of this method to palaeotsunamis, the continuous monitoring of water-soluble ions in tsunami-inundated soil is needed as a future study.  相似文献   

Strike–slip origin of Cretaceous Mazhan Basin, Tan-Lu Fault Zone, Shandong, east China     

Jingpeng Hong  & Takao Miyata 《Island Arc》1999,8(1):80-91

The Mazhan Basin, Shandong Province, China, is located between the main faults, F₃ and F₄, of the Tan-Lu Fault Zone. It is an elongated basin more than 60 km in length and 8 km in width and contains a series of typical continental sediments (the Upper Cretaceous Wangshi Group). This series was divided into three sedimentary facies associations: conglomerate facies association; sandstone facies association of alluvial fan to lake margin environment; and siltstone facies association of lacustrine origins. Their zonal distribution pattern may represent a contemporaneous heterotopic facies due to a lateral facies change from margins to axis of the basin. Their stratigraphic sequence becomes younger northward along the boundary faults. This suggests that the depocenter of the fan–lake system tends to migrate northward along F₃. From the asymmetric features (i.e. basin shape, lithofacies distribution, facies change) the Mazhan Basin can be explained by progressive subsidence at the Tangwu releasing bend of F₃ with sinistral strike–slip movement. Judging from the fission track (FT) ages from the Wangshi Group, it was concluded that a sinistral strike–slip movement along the main fault, F₃ of the Tan-Lu Fault in Shandong, has lasted until the Late Cretaceous. Its displacement is estimated to be larger than the migrated distance, 60 km, of the depocenter of the Mazhan Basin.  相似文献   

Paleomagnetism of Cretaceous Red beds from Eastern Part of South China Block     

Hayao Morinaga  Hiroyuki Kashimura 《中国地质大学学报(英文版)》1999,10(3)

INTRODUCTIONCollisionofIndiawithAsiaappearstohavebroughtaboutlargetectonicdeformationofAsia,especiallyEastAsia(Tapponnieretal.,1986).Post-Cretaceousdeformation(translationand/orrotation)ofSimaoandIndochinablocks,whicharelocatedatthesouthernsideofRedRiverfault(RRF),hasbeenreportedfromCretaceouspaleomagneticin-vestigations(Yangetal.,l995;HuangandOpdyke,l993IYangandBesse,1993).AlsoinSouthChinablock(SCB)locatedatnorthsideoftheRRF,localdeformationofsomeregionsneartheRRFhasbeendocum…  相似文献   

Development of new sensor systems for continuous bedload monitoring using a submerged load‐cell system (SLS)          下载免费PDF全文

Takahiro Itoh  Takahiko Nagayama  Rei Utsunomiya  Masaharu Fujita  Daizo Tsutsumi  Shusuke Miyata  Takahisa Mizuyama 《地球表面变化过程与地形》2018,43(8):1689-1700

It is important to evaluate bedload discharge and temporal changes of the bed surface, and bed deformation can be estimated during floods if the bedload discharge is properly evaluated in an arbitrary cross‐section. With the exception of grain size and its distribution within the bedload, bedload discharge has been measured using both direct and indirect methods. Bedload slot is a direct method but cannot be used to measure bedload during a flood because of volume limitations. Indirect methods require correlation between the signals and sediment volume measured using another method. In the present study, a small, automatically recording bedload sensor with an iron plate and a pair of load cells is developed in order to evaluate not only large particles but also sand particles as bedload. Bedload mass is calculated by integrating with respect to both the velocity of sediment particles and the averaged particle weight as measured by a pair of load cells, and, as an example, the velocity is estimated by the cross‐correlation function of weights measured by load cells. The applicability of the proposed sensor is discussed based on the results of flume tests in the laboratory (2014) and the observation flume of the Hodaka Sedimentation Observatory of Kyoto University in Japan (2015). The system was installed in the observation flume in November of 2012, and flume data were obtained using natural sediment particles. In particular, it was difficult to estimate the velocity of averaged bedload particles, and it was better to apply a cross‐correlation function in the laboratory tests. However, it appears that the previous estimation can estimate these velocities in the observation flume using a connecting tube and submerged load‐cell systems. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献