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81.
In order to compare the acute toxicity of tributyltin (TBT) between sexes, five species of caprellid amphipods were exposed to seven levels (0, 0.001, 0.01, 0.1, 1, 10 and 100 microg l(-1)) of TBT for 48 h at 20 degrees C. The 48-h LC50 values in male and female were 1.3-6.4 microg TBTCl l(-1) and 1.2-8.6 microg TBTCl l(-1), respectively. No sex-specific differences of the acute toxicity of TBT were observed in the caprellids. These findings suggest that the risk of survival in response to exposure to TBT between sexes is similar in the caprellids.  相似文献   
82.
The present study proposes an atmospheric correction scheme for Advanced Earth Observation Satellite II (ADEOS-II)/Global Imager (GLI) ocean color retrieval that corrects for the atmospheric absorptive aerosol effect. Radiative transfer simulations were conducted assuming a non-absorptive model aerosol with a soot-type aerosol at various mixture ratios. The results indicate that while the spectral dependency of aerosol reflectance does not change in the longer (>550 nm) wavelength region, the reflectance at shorter wavelengths is highly variable and depends on the mixture ratio. The influence of aerosol absorption was also investigated using GLI data from ocean areas adjacent to Japan in the presence of absorptive Siberian fire smoke aerosol in the spring of 2003. The spectral curvature of the aerosol was estimated from the data obtained. An empirical, iterative scheme that detects and evaluates the influence of absorptive aerosols was developed by comparing 380 nm GLI-observed aerosol reflectance with predicted reflectances derived using an in-water optical model. To evaluate the performance of this scheme, satellite-derived normalized water-leaving radiances were compared with those measured from a ferry servicing Nagasaki and Fukue. The results of data acquired on March 20, 2003, indicate that this absorption correction scheme improved root mean square estimation error for normalized water-leaving radiance by approximately 40% in the 380, 400, and 412 nm bands. This atmospheric correction algorithm was used as a part of the second version of the GLI standard ocean color data process system at Japan Aerospace Exploration Agency (JAXA).  相似文献   
83.
We developed a procedure solving Gauss' form of Kepler's equation, which is suitable for determining position in the nearly parabolic orbits. The procedure is based on the combination of asymptotic solutions, the method of bisection, and the Newton method of succesive correction. It runs 3–4 times faster than the original Gauss' method. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
84.
The 17 August 1999 Kocaeli earthquake in Turkey produced a majorsurface rupture. We traced this surface rupture from Gölcük toDüzce and located it accurately by using GPS. The closest distancefrom the surface rupture to the strong motion observation sites weredetermined. Then the attenuation characteristics of the observed peakground acceleration were compared with the attenuation relation given byFukushima and Tanaka (1992), which is suitable for the near-fault zone inJapan and gives results that closely match data recorded during the 1995Hyogo-ken Nanbu earthquake in Japan. Although this attenuation relationwas developed for Japan, we found that it agreed well with the KOCAELIearthquake. Furthermore, the observed spectral acceleration of 5%damping was compared with the building design code of Turkey and theobserved level was lower than the code.  相似文献   
85.
The nitrogen-doped TiO2 nanotube (N-TNT) thin films were synthesized using ZnO nanorods as the template and doped with urea at 623 K. Under ultraviolet (UV) and visible light irradiation, the efficiencies for photocatalytic degradation of methylene blue is as high as 30%. About 10% of toluene (representing aromatics in the spill oils) in sea water can be photocatalytically degraded under visible light radiation for 120 min. The aliphatic model compound (1-hexadecene) has, on the contrary, a less efficiency (8%) on the N-TNT photocatalyst. On the average, under visible light radiation, the effectnesses of the N-TNT for photocatalytic degradation of model compounds in the spill oils in sea water are 0.38 mg toluene/gN-TNT h and 0.25 mg 1-hexadecene/gN-TNT h. It is expected that spill oils in the harbors or seashores can be adsorbed and photocatalytically degraded on the N-TNT thin films that are coated onto levee at the sea water surface level.  相似文献   
86.
87.
A new canonical transformation of freedom two was found. By using this, we derived three new sets of canonical variables for the orbital motion and two for the rotational motion. New canonical variables have clear physical meanings and remain well-defined in the case when the classical sets become ill-defined, for example, when the eccentricity and/or the inclination is small for the elliptic orbital motion.  相似文献   
88.
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