The dissolved inorganic carbon and total alkalinity in the surface brackish waters of Lake Hamana were investigated monthly from October 2017 to September 2019 at 14 stations. The partial pressure of carbon dioxide (pCO2) in the surface water ranged from 29 to 1476 μatm and was undersaturated for atmospheric CO2 during the observation periods, although most coastal waters were net source areas because of the large amount of terrestrial organic and inorganic carbon input. Since there was a strong negative correlation between pCO2 and the dissolved oxygen, seasonal and temporal variations in pCO2 were mainly derived from phytoplankton activity. The high phytoplankton activity induced by the effluents from sewage treatment plants, which was low in carbon and high in nitrogen. Therefore, in urbanized coastal waters with sewage treatment plants, such as the coastal waters of Japan, there is a possibility of shifting from weaker carbon dioxide source areas to sink areas. However, pCO2 was oversaturated at the polluted river mouth, especially after high precipitation events due to the large carbon supply.
The Solar Optical Telescope (SOT) aboard the Solar-B satellite (Hinode) is designed to perform high-precision photometric and polarimetric observations of the Sun in visible light spectra (388 – 668 nm)
with a spatial resolution of 0.2 – 0.3 arcsec. The SOT consists of two optically separable components: the Optical Telescope
Assembly (OTA), consisting of a 50-cm aperture Gregorian with a collimating lens unit and an active tip-tilt mirror, and an
accompanying Focal Plane Package (FPP), housing two filtergraphs and a spectro-polarimeter. The optomechanical and optothermal
performance of the OTA is crucial to attain unprecedented high-quality solar observations. We describe in detail the instrument
design and expected stable diffraction-limited on-orbit performance of the OTA, the largest state-of-the-art solar telescope
yet flown in space. 相似文献
—We examine the possibility of seismic anisotropy in the asthenosphere due to present plate motion using SKS splitting results. The fast directions of anisotropy correlate weakly with the directions of the absolute plate motion (APM) for all APM models. Weak correlation indicates the possibility of asthenospheric anisotropy as well as frozen anisotropy in the lithosphere. Detection of strain rate dependence of anisotropy is helpful to further conclusion of the problem. The selection of reference frame is important to describe shear deformation in the asthenosphere beneath continent due to plate motion. The behavior of hot spots to the mesosphere, fixed or drifted by mantle return flow, is a key of the selection of the reference frame. For the NNR-NUVEL1 model, APM correlated anisotropy appears only at plate velocity faster than 1.4 cm/yr. It suggests the new possibility of the formation of asthenospheric anisotropy in addition to frozen anisotropy in the lithosphere. A critical plate velocity for the formation of anisotropy can be caused by the dislocation-diffusion transition as a function of strain rate on a deformation mechanism map of the upper mantle olivine. 相似文献
Spectroscopic observation of solar flares in the hard X-ray energy range, particularly the 20 ∼ 100 keV region, is an invaluable
tool for investigating the flare mechanism. This paper describes the design and performance of a balloon-borne hard X-ray
spectrometer using CdTe detectors developed for solar flare observation. The instrument is a small balloon payload (gondola
weight 70 kg) with sixteen 10×10×0.5 mm CdTe detectors, designed for a 1-day flight at 41 km altitude. It observes in an energy
range of 20−120 keV and has an energy resolution of 3 keV at 60 keV. The second flight on 24 May 2002 succeeded in observing
a class M1.1 flare. 相似文献
Perturbations in the motion of the Moon are computed for the effect by the oblateness of the Earth and for the indirect effect of planets. Based on Delaunay's analytical solution of the main problem, the computations are performed by a method of Fourier series operation. The effect of the oblateness of the Earth is obtained to the second order, partly adopting an analytical evaluation. Both in longitude and latitude are found a few terms whose coefficient differs from the current lunar ephemeris based on Brown's theory by about 0.01. While, concerning the indirect effect of planets, several periodic terms in the current ephemeris seem to have errors reaching 0.05.As for the secular variations of
and due to the figure of the Earth and the indirect effect of planets, the newly-computed values agree within 1/cy with Brown's results reduced to the same values of the parameters. Further, the accelerations in the mean longitude,
and caused by the secular changes in the eccentricity of the Earth's orbite and in the obliquity of the ecliptic are obtained. The comparison with Brown shows an agreement within 0.3/cy2 for the former cause and 0.02/cy2 for the latter. An error is found in the argument of the principal term for the perturbations due to the ecliptic motion in the current ephemeris.Proceedings of the Conference on Analytical Methods and Ephemerides: Theory and Observations of the Moon and Planets. Facultés universitaires Notre Dame de la Paix, Namur, Belgium, 28–31 July, 1980. 相似文献
An orthogonal set of principal axes is defined for earthquake ground motions. These principal axes are obtained such that the corresponding variances of motion have maximum, minimum and intermediate values and the covariances equal zero. This indicates that the corresponding components of motion along the principal axes are uncorrelated with respect to each other. Since real earthquake accelerograms are assumed to be reasonably well represented by Gaussian random processes, the three components of motion along the principal axes are statistically independent of each other. Using these principal axes and applying the moving-window technique to the ground accelerograms recorded during the San Fernando earthquake of 9 February 1971, time-dependent characteristics of three-dimensional ground motions along principal axes are determined. Results of the analysis indicate significant correlation between directions of principal axes and directions from the recording stations to the fault slip zone. It is concluded that three components of ground motion can be generated stochastically with statistical independence being maintained, provided they are assumed to be directed along principal axes. 相似文献
In this paper, we propose a numerical simulation procedure of moored ship motions due to initial attack of large-scaled tsunamis and investigate the effects on the motions and mooring loads. The effect of methodology on selection of tsunami wave components and of the drag forces are then considered by using the numerical simulation method, applying to several case studies for LNG-carrier. Large ship motions and excessive mooring loads beyond the safe working loads are induced by the resonant tsunami wave components in the sway and surge motions and drag forces. 相似文献
Transportation is one of the most important and urgent tasks in a disaster, e.g., earthquake or flood. Trains, trucks and cars are very restricted by destruction of rail and road, bridges and buildings fall down, flood waters and thick mud, landslides, cracks, level differences, severe traffic jam etc. Sunken objects in the water and damages of quays prevent ships from reaching harbors. The situation remains days, weeks and even months.Hovercraft can run on almost every surface: ground, water surface, mud, sands, grits, weeds etc. The performance is very favorable in the first-aid transportation in a disaster.A middle size hovercraft with payload of 2–3 tons is suitable for first-aid work in a disaster. The amount of load is appropriate for loading and unloading by manpower without using a special loading machine. Small loads with frequent return trip are desirable to fulfill needs that are changing from time to time. A system of first-aid transportation by a number of hovercraft of middle size is proposed in this paper as an additional system of transportation to existing ones. The system is very useful for first-aid transportation in a disaster.A simulation of hovercraft transportation was carried out after the Kobe Earthquake in 1995 as an example. We assume that 20 hovercraft of middle size are operated from 6 bases just outside of the disaster area to 12 destinations in the area. The result shows that they can transport up to 1,200 tons goods in a day in addition to those of conventional transportation means without disturbing them. 相似文献