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131.
During the 1982 and 1983 Balloon Intercomparison Campaigns, the vertical profile of stratospheric NO2 was measured remotely by nine instruments and that of NO by two. Total overhead columns were measured by two more instruments. Between 30 and 35km, where measurements overlapped, agreement between NO profiles was within ±30%, which is better than the accuracies claimed by the experimenters. Between 35 and 40km there was similarly good agreement between NO2 profiles, but below 30km, differences of greater than a factor three were found. In the second Campaign, NO2 values from most instruments agreed within their quoted errors, except that the Oxford radiometer gave much lower values; but the first Campaign and the column measurements show a more uniform spread of results.These differences below 30km could not be resolved, but new laboratory measurements are planned which should do so.  相似文献   
132.
Nine submersible dives were made in three trenches off central Japan, between 2990 and 5900 m of water depth. Our observations confirm the interpretation that Daiichi-Kashima Seamount is a Cretaceous guyot formed on the Pacific plate that has traveled into the Japan Trench. We also confirmed the previous interpretation of a large normal fault that splits the seamount in two halves, the lower one being now subducting beneath the Japan margin. Compressional deformation was identified within the lower part of the inner slope in front of the seamount. The pattern of deformation that affects Quaternary sediments is in agreement with the present kinematics of the convergence between the Pacific plate and Japan. Deep-water (5700 m) clam colonies are associated with advection of fluids, driven by the subduction-related overpressures. In the northern slope of the Boso Canyon, along the Sagami Trough system (Philippine Sea plate-Japan boundary), the deformation affecting a thick upper Miocene to lower Pliocene sequence indicates two directions of shortening: a N175°E direction which is consistent with the present relative motion along the Sagami Trough (N285–N300°E) and a N30°E direction which could be related to a more northerly direction of convergence that occured during the early Quaternary and earlier.  相似文献   
133.
134.
The integrated equations of deep sea mooring lines in static equilibrium under consideration of gravity force and line elongation are obtained. The most useful forms of the equations for designing deep sea mooring system are those in which horizontal displacement and horizontal and vertical components of tension are obtained as functions of line length, water depth, critical tension and unit weight of line.When the dynamic simulation of a buoy system is carried out, line tensions acting on the buoy should be represented as a linear function of displacement. Therefore the linearisation method is introduced by use of linearisation coefficient matrix. Translation formulae for the matrix from two to three dimensions is also presented.The influence of line elongation on the horizontal component of tension in a taut mooring condition is important, therefore the elongation of stretched deep sea mooring line must be considered carefully. Also, the scaling law under consideration of line elongation in static equilibrium, which is necessary in estimation from a small sized experiment, is discussed.  相似文献   
135.
136.
High-temperature and high-pressure recovery experiments were made on experimentally deformed olivines at temperatures of 1613–1788 K and pressures of 0.1 MPa to 2.0 GPa. In the high-pressure experiments, a piston cylinder apparatus was used with BN and NaCl powder as the pressure medium, and the hydrostatic condition of the pressure was checked by test runs with low dislocation density samples. No dislocation multiplication was observed. The kinetics of the dislocation annihilation process were examined by different initial dislocation density runs and shown to be of second order, i.e.
dρdt= ?p2K0exp[?(E1+PV1RT]
where ρ is the dislocation density, k0 is a constant, E1and V1 are the activation energy and volume respectively, and P, R and T are pressure, gas constant and temperature, respectively. Activation energy and volume were estimated from the temperature and pressure dependence of the dislocation annihilation rate as E1=389±59 kJ mol?1 and V1=14±2 cm3mol?1, respectively.The diffusion constants relevant to the dislocation annihilation process were estimated from a theoretical relation k=αD where k=k0 exp[?(E1 + PV1)/RT], D is the diffusion constant and α is a non-dimensional constant of ca. 300. The results agree well with the self-diffusion constant of oxygen in olivine. This suggests that the dislocation annihilation is rate-controlled by the (oxygen) diffusion-controlled dislocation climb.The mechanisms of creep in olivine and dry dunite are examined by using the experimental data of static recovery. It is suggested that the creep of dry dunite is rate-controlled by recovery at cell walls or at grain boundaries which is rate-controlled by oxygen diffusion. Creep activation volume is estimated to be 16±3 cm3 mol?1.  相似文献   
137.
The hydroxyl column abundance in the middle atmosphere is measured for 3 years in Tokyo by ground-based uv absorption spectroscopy utilizing the Doppler shift of the solar spectrum due to the solar rotation. The diurnal and seasonal variations of the measured column abundance are found to be reproduced qualitatively by a one-dimensional photochemical-diffusive model; however, the measured column abundances are smaller than the calculated by 20 to 30% systematically.  相似文献   
138.
1 INTRODUCTIONSolar ultraviolet radiation on the earth's surfaceincreases with the depletion of stratospheric ozone(Crutzen, 1992; Kerr and McElroy, 1993; Mad-ronich et al., 1998). Ultraviolet radiation is a highlyactive component of solar spectrum. The excessiveUV radiation has deleterious effects on all plant,animal and microbial groups exposed to solar radia-tion, including the destruction of DNA, proteins andother molecules (Harm, 1980), inhibition of photo-synthesis and growth (W…  相似文献   
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