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51.
Functions of the major cheliped in pagurid hermit crabs have been studied in fights for shells. The major cheliped often shows
sexual size dimorphism, suggesting that sexual selection favors the development of the male major cheliped. The function of
the major cheliped in male–male competition was examined in Pagurus nigrofascia collected from April to June 2009 on the intertidal rocky shore in southern Hokkaido, Japan (41°N, 140°E). Sexual size dimorphism
of the major cheliped was observed, and precopulatory guarding males had larger major chelipeds than solitary ones. Guarding
males used the major cheliped to deter intruders during competitive interactions. Males without a major cheliped were disadvantaged
even if they were larger than opponents and had ownership. Cheliped size affected the outcomes of contests between similar
sized males. This suggests that the male major cheliped in P. nigrofascia protects mates from competitors and, consequently, enhances male mating success. Sexual selection may favor the development
of the major cheliped in male pagurids. 相似文献
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Saito-Kokubu Y Yasuda K Magara M Miyamoto Y Sakurai S Usuda S Yamazaki H Yoshikawa S Nagaoka S Mitamura M Inoue J Murakami A 《Journal of environmental radioactivity》2008,99(1):211-217
In a sediment core of Nishiyama reservoir at Nagasaki city, depth profiles of (240)Pu/(239)Pu isotopic ratio, (239+240)Pu and (137)Cs activities were determined. Sediments containing plutonium and (137)Cs, which were deposited immediately after a detonation of Nagasaki atomic bomb, were identified in the core. Observed below the sediments were macroscopic charcoals, providing evidence for initial deposit of the fallout of the Nagasaki atomic bomb. This is the first entire depositional records of plutonium and (137)Cs released from the Nagasaki atomic bomb together with those from atmospheric nuclear tests. 相似文献
54.
Ide J Chiwa M Higashi N Maruno R Mori Y Otsuki K 《Environmental monitoring and assessment》2012,184(8):4747-4762
This study sought to determine the lowest number of storm events required for adequate estimation of annual nutrient loads from a forested watershed using the regression equation between cumulative load (∑L) and cumulative stream discharge (∑Q). Hydrological surveys were conducted for 4 years, and stream water was sampled sequentially at 15-60-min intervals during 24 h in 20 events, as well as weekly in a small forested watershed. The bootstrap sampling technique was used to determine the regression (∑L-∑Q) equations of dissolved nitrogen (DN) and phosphorus (DP), particulate nitrogen (PN) and phosphorus (PP), dissolved inorganic nitrogen (DIN), and suspended solid (SS) for each dataset of ∑L and ∑Q. For dissolved nutrients (DN, DP, DIN), the coefficient of variance (CV) in 100 replicates of 4-year average annual load estimates was below 20% with datasets composed of five storm events. For particulate nutrients (PN, PP, SS), the CV exceeded 20%, even with datasets composed of more than ten storm events. The differences in the number of storm events required for precise load estimates between dissolved and particulate nutrients were attributed to the goodness of fit of the ∑L-∑Q equations. Bootstrap simulation based on flow-stratified sampling resulted in fewer storm events than the simulation based on random sampling and showed that only three storm events were required to give a CV below 20% for dissolved nutrients. These results indicate that a sampling design considering discharge levels reduces the frequency of laborious chemical analyses of water samples required throughout the year. 相似文献
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Tohru Kamo Beili Wu Yuriko Egami Hajime Yasuda Hideki Nakagome 《Journal of Material Cycles and Waste Management》2011,13(1):50-55
Steam gasification in the presence of carbonate compounds is an effective method to recover useful materials from electronic
waste streams by converting plastics into gaseous products that can be used for energy production and avoiding the expensive
manual disassembly process. We investigated steam gasification of activated carbon in the presence of various mixtures of
lithium carbonate, sodium carbonate, and potassium carbonate. The activated carbon was almost completely converted into hydrogen
and carbon dioxide at 700°C under 0.1 MPa pressure in the presence of carbonate mixtures. Carbon dioxide was also derived
from partial decomposition of lithium carbonate. Steam gasification was accelerated in the presence of various carbonate mixtures
and at increasing steam partial pressures. These experimental results show that fluidity of carbonates, the potassium content
of the carbonate, and the steam partial pressure are important factors in accelerating steam gasification. 相似文献
56.
Tsutomu Aoshima Mitsuharu Kajita Yoshitaka Sekido Shunji Mimura Atsuo Itakura Izumi Yasuda Takeyori Saheki Kazuyoshi Watanabe Kaoru Shimokata Toshimitsu Niwa 《黑龙江环境通报》2001,21(8):634-637
We report a Japanese boy who died at Day 28 of life because of severe carbamoyl phosphate synthetase I (CPS1) deficiency that was proven by enzyme assay. By analysis of cDNA and genomic DNA, he was shown to be a compound heterozygote with two point mutations of the CPS1 gene, 840G>C leading to an aberrant splicing and 1123C>T (predicting Q375X). The 840G>C was a mutation described in another Japanese family. Since his parents carried each mutation heterozygously, we performed prenatal diagnosis at 16 weeks of his mother's next gestation by multiplex PCR and melting curve analysis in a single capillary containing two-color fluorescent (LC-Red 640 and LC-Red 705) probes on LightCycler. We analyzed genomic DNA extracted from amniotic cells and found that the fetus was homozygous for the wild-type alleles. At term a healthy girl was born without hyperammonemia. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
57.
Naoko Seino Hidetaka Sasaki Junji Sato Masaru Chiba 《Atmospheric environment (Oxford, England : 1994)》2004,38(40):7073
After severe eruptions of the volcano at Miyake Island in August 2000, a large amount of volcanic gas was released into the atmosphere. To simulate flows and dispersion of sulfur dioxide (SO2) over Miyake Island, a set of numerical models was developed. The multi-nesting method was adopted to reflect a realistic meteorological field and to sufficiently resolve the flow over the island with a diameter of 8 km. The outermost model was the Regional Spectral Model (RSM) of the Japan Meteorological Agency (JMA) with a horizontal grid size of 10 km. Finer atmospheric structure was simulated with the nonhydrostatic model jointly developed by the Meteorological Research Institute and the Numerical Prediction Division of JMA (MRI/NPD-NHM) with grid intervals of 2 km, 400 m and 100 m. Realistic topography of the island was represented in the innermost model. The Lagrangian particle method was applied to the dispersion model, which is driven by the meteorological field of the 100 m grid MRI/NPD-NHM. The random walk procedure was used to represent the turbulent diffusion. The model was verified in four cases. Simulated SO2 concentrations agreed well with observed concentrations at a monitoring station including temporal variation. Under a large synoptic change, however, accurate prediction became difficult. Further numerical experiments have been done to investigate characteristics of the flow and the distribution of SO2. Steady inflows, classified according to the surface wind speed and direction, were assumed. Simulated SO2 distribution on the ground apparently depends on the surface wind. Under relatively weak inflow, there is a large diurnal change in SO2 distribution, affected by the thermally induced flow. SO2 gas is widely spread downstream in the nighttime but hardly reaches the coastal area in the daytime. On the other hand, SO2 gas steadily reached the downstream coast with little diurnal variation under the stronger inflow. Ground temperature, as well as the static stability of the inflow, also influences downstream wind, turbulent diffusivity and SO2 distribution. 相似文献
58.
Kisei Kinoshita Wang Ning Zhang Gang Andrew Tupper Naoko Iino Satoshi Hamada Satoshi Tsuchida 《Water, Air, & Soil Pollution: Focus》2005,5(3-6):89-100
Monitoring of Asian dust at two stations in Changchun, Jilin Province in northeast China, and Kagoshima, southwest Japan,
is discussed. In Changchun, interval records were made with digital and video cameras from 18 March 2003. In Kagoshima, a
web camera system to monitor volcanic clouds has been working since December 2000, which also provides data for studies of
dust. A heavy dust episode on 11 November 2002, affecting both stations, was detected using 11 and 12 μm channels of NOAA/AVHRR.
We observed dust in Changchun on 26 March, 7, 14–16 April, 1–2, 8, 10, 19 May, 8, 23 June, and 12 July in 2003. The observed
images corresponded well to NOAA/AVHRR imagery and with 8.6, 11 and 12 μm Terra/MODIS results, although conditions were too
cloudy for satellite verification in some cases. 相似文献
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电子产品的生产者责任延伸制和设计革新--来自日本和欧洲的例子 总被引:2,自引:0,他引:2
电子产品(EEE)包括了从大型和小型家用电器(冰箱、微波炉、空调、烤面包机和剃须刀等).信息与通信技术(ICT)设备(电话、电脑等)到玩具、照明设备和医疗设备等各种产品。由于电子产品数量越来越多,并且含有有害物质.所以这些产品不能够进行掩埋和焚烧处理。随着技术的高速发展,电子产品的种类也越来越多.这使普通的地方回收站疲于应付。而且回收处理站点不能够从生产商方面得到足够的产品信息.这使得形势更加严峻。而且对于废弃产品不恰当的处理更会导致有用资源的浪费。 相似文献