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11.
Sadao Matsuo 《Bulletin of Volcanology》1962,24(1):59-71
The establishment of gaseous chemical equilibrium in gases obtained from Kilauea lava lake was studied. Using Shepherd’s elaborate analytical data, we examined six chemical reactions in the gas phase and concluded that they were in equilibrium. The gases reflected the « quenched » equilibrium conditions of temperature within a range from 1,000° C to 1,200° C under 1 atmosphere. The gas samples had been collected over a period of three years in different localities of the same lava lake. Although the analytical result was varied considerably for each sample, the establishment of chemical equilibrium was confirmed in five of the six reactions, the exception being due to sulfur trioxide in the sixth. 相似文献
12.
Since August 1974 the authors have been carrying out an experiment on creep by bending three small granite beams and three gabbro beams. While making measurements, an optical flat is set to produce interference fringes of Na-D light upon the upper polished surface of the beam, which was previously bent convex upward. By analyzing the fringes the profile of the surface is determined with in an accuracy of one-tenth of a wavelength. The routine determination of profiles gives a change in the amount of bending with time.A similar experiment on two large beams of granite was carried out for 21 years by Kumagai and Itô. It took 10 years in order to find out the secondary creep of granite. However, in this three-year experiment it has been found that the secondary creep of the granite specimens gives a viscosity of about 1 · 1020 poise, which is comparable to that obtained over 20 years in the previous experiment (Kumagai and Itô). As for the gabbro specimens, the present authors cannot yet definitely recognize the secondary creep, because gabbro creeps much more slowly than granite.Both this and the previous experiments have revealed that the creep of rocks does not show a steady and monotonous progress, but a repeated “turn back” with various periods, some of which are longer than one year. In order to explain the creep accompanied by the “turn back” phenomenon, the authors venture to hypothesize that the elastic constants of a test-piece slightly vary with time during the advance of creep. 相似文献
13.
Relationship between the increase temperature and variation of ozone level over the Antarctica and Tibetan plateau in spring 总被引：1，自引：0，他引：1
Based on the ozone and aerological sounding data at Syowa Station (69o 00'S, 39o35'E), Antarctica during 1966－1979 and Lhasa Station (39o40'N, 91o08'E), Tibetan Plateau during 1979－1983, the processes of temperature increase in spring over the Tibetan Plateau and the Antarctica are compared in this paper, and the relationship between the increase of air temperature and variation of total ozone and ozone partial pressure is analyzed. It is found that: (1) The process of temperature increase over the Tibetan Plateau is quite different from that over the Antarctica in spring. This is a proof that the heating effects of their ground surface on the atmosphere are of great difference; (2) Sudden increase of total ozone is always associated with sudden warming in the stratosphere over the Antarctica, but sudden decrease of total ozone is associated with sudden warming in the troposphere over the Tibetan Plateau in spring; and (3) There is a good positive correlation, with a correlation coefficient of about 0.85, between the temperature increase and variation of ozone partial pressure in the stratosphere over the Antarctica in spring. 相似文献
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We examined change in areal extent of mountain meadows and fields of deciduous shrubs and conifer saplings in the central western Cascade Range of Oregon, based on analysis of aerial photographs taken in 1946 and 2000. These nonforest vegetation patches are distinctive habitats in dominantly forested landscapes, such as the Cascades, and change in extent of these habitats is of interest to scientists and land managers. We mapped and dated even-aged forest stands of probable postfire origin around the nonforest patches, using tree-ring analysis and interpretation of aerial photographs. We used these and archival data to interpret possible influences of past wildfire and sheep grazing on the extent of nonforest patches. The total area of nonforest vegetation patches decreased from 5.5 percent of the study area in 1946 to 2.5 percent in 2000. Significantly more cases of contracted patches were observed for mesic and xeric meadows which have adjacent forest established after wildfire in the approximately 150 years preceding 1946. A higher proportion of mesic (47 percent, n = 47) than xeric (17 percent, n= 115) meadows contracted between 1946 and 2000. Broad-leaved shrub fields were unchanged, probably because of topo-edaphic controls, dense cover of shrubs, and snow effects; but all fields of conifer saplings underwent succession to forest. We observed no strong influences of sheep grazing on the extent of meadows. 相似文献
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The hydrogen isotopic fractionation factor between brucite and water has been determined in the temperature range of 100°–510° C. Brucite is always depleted in deuterium relative to the coexisting water, and the degree of depletion becomes larger with decreasing temperature. The fractionation factor changes smoothly in the temperature range of 144°–510° C and its temperature dependence was obtained by the method of least square fit in the following form: 103In=8.72×106
T
–2–3.86×104
T
–1+14.5However, a marked decrease of about 5 was observed at 100°–144° C. The D/H fractionation factor for the brucite-water system is not similar to that for serpentine-water system presented by Sakai and Tsutsumi (1978), though all the hydroxyl ions coordinate to magnesium ion in both minerals. This discrepancy cannot be attributed to hydrogen bonding but to distortion of Mg-octahedron of serpentine, in which the Mg-OH bonding length is shorter than the sum of ionic radius of Mg2+ and O2– and there is no distortion in brucite. It is indicated that aside from hydrogen bonding, the structure effect also controls the D/H fractionation between hydrous mineral and water. 相似文献
18.
Yo-ichiro Otofuji Sadao Sasajima Susumu Nishimura Agus Dharma Fred Hehuwat 《Earth and Planetary Science Letters》1981,54(2):272-280
Paleomagnetic results from the northern arm of Sulawesi show that the arm has been subjected to a clockwise rotation of more than 90° and that its rotational motion began no later than the middle Miocene. The mean direction showing a normal polarity at the Eocene to the early Miocene isD = 98.0° andI = 6.9°. A declination value ofD = 50.1° obtained from Miocene rocks indicates a transition stage of the rotational motion. The datum from Plio-Pleistocene volcanics isD = ?4.6° andI = ?9.3°. This suggests that the rotational motion terminated before the initiation of volcanic activity during the Plio-Pleistocene. 相似文献
19.
Koichi Ara Koh Yamaki Keisuke Wada Satoshi Fukuyama Takeshi Okutsu Sadao Nagasaka Akihiro Shiomoto Juro Hiromi 《Journal of Oceanography》2011,67(1):87-111
Seasonal and interannual variations in physicochemical properties (i.e., temperature, salinity, dissolved oxygen and dissolved
inorganic nutrients), chlorophyll a (Chl-a), particulate carbon and nitrogen (PC and PN, respectively), and primary production were investigated in the neritic area
of Sagami Bay, Kanagawa, Japan, from January 2002 to December 2008. These abiotic/biotic variables, except for NH4
+–N, repeated similar seasonal variations for all 7 years. On the basis of the analysis of data obtained on 167 sampling dates,
depth-integrated primary production in this water can be easily estimated from Chl-a at the surface using the regression equations obtained in the present study. Intermittently high values of dissolved inorganic
nutrients, Chl-a, PC, PN and primary productivity at the surface during the summer stratified period were induced by high freshwater discharge
from the rivers after rainfalls and by the expansion of nutrient-rich Tokyo Bay Water. Temperature, salinity and dissolved
inorganic nutrients showed drastic variations within a scale of a few days and/or weeks, and these variations were related
to sea levels that represent the intrusion of the Kuroshio Water, Intermediate Oyashio Water or deep water from the continental
slope. However, there was no consistent trend in the variations in Chl-a, PC, PN and primary production due to the complex effects of these waters. 相似文献
20.
LIU Chen Kuninori OTSUBO WANG Qinxue Toshiaki ICHINOSE Sadao ISHIMURA 《中国地理科学(英文版)》2007,17(2):99-109
By studying the county-level census data of 1990 and 2000, we analyzed the spatial and temporal changes in the floating population in China between 1990 and 2000. The results of the analysis revealed the following characteris- tics. First, the spatial distribution of the migrants (referred to as 'floaters' in this paper) became increasingly concentrated in the cities during the 1990s. Second, the number of floaters increased rapidly during this period, and the area in which the floaters settled expanded quickly into four population explosion belts: the coast, the Changjiang River Delta, the Beijing-Guangzhou Railway and national border belts. Third, the number of inter-province floaters increased rapidly and exceeded that of intra-province floaters in the 1990s. In addition, to obtain a quantitative relationship between the number of floaters and 10 socio-economic variables by using statistical methods and also to find the chiefly important pulling factors of the migration destination, the authors selected approximately 100 cities with the largest population of floaters. Consequently, we found that four factors-GDP, passenger trips per 10,000 persons, per capita GDP and foreign direct investment-could provide an explanation for 83.7% of the number of floaters in 2000. The GDP showed the highest correlation with the number of floaters, suggesting that a highly developed economy is the most important factor that attracts floaters. Furthermore, a fairly close relationship between the number of floaters and the GDP was also found in 2000 for all the counties. 相似文献