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91.
使用移动式亚毫米波望远镜(POST)在位于青藏高原海拔3200米的紫金山天文台德令哈射电天文观测站址测量地球大气492GHz频率处天顶方向的不透明度(τ0)的结果.在1999—2000年冬季和2000—2001年冬季的两个观测季节内累计共进行了约870个小时的测量,取得了25842组τ0的有效数据.对数据的统计表明,观测季节内τ0值主要分布在1.5—3.0之间.观测时段内大气不透明度τ0≤1.0的时间比例约占3%.在给出实测资料的基础上,将所测量的亚毫米波不透明度与国际现有亚毫米波台址的不透明度进行了初步比较.  相似文献   
92.
The primary motivation for the vehicle replacement schemes that were implemented in many countries was to encourage the purchase of new cars. The basic assumption of these schemes was that these acquisitions would benefit both the economy and the environment as older and less fuel-efficient cars were scrapped and replaced with more fuel-efficient models. In this article, we present a new environmental impact assessment method for assessing the effectiveness of scrappage schemes for reducing CO2 emissions taking into account the rebound effect, driving behavior for older versus new cars and entire lifecycle emissions for during the manufacturing processes of new cars. The assessment of the Japanese scrappage scheme shows that CO2 emissions would only decrease if users of the scheme retained their new gasoline passenger vehicles for at least 4.7 years. When vehicle replacements were restricted to hybrid cars, the reduction in CO2 achieved by the scheme would be 6–8.5 times higher than the emissions resulting from a scheme involving standard, gasoline passenger vehicles. Cost–benefit analysis, based on the emission reduction potential, showed that the scheme was very costly. Sensitivity analysis showed that the Japanese government failed to determine the optimum, or target, car age for scrapping old cars in the scheme. Specifically, scrapping cars aged 13 years and over did not maximize the environmental benefits of the scheme. Consequently, modifying this policy to include a reduction in new car subsidies, focused funding for fuel-efficient cars, and modifying the target car age, would increase environmental benefits.  相似文献   
93.
The study area is located in Kawakami-cho, Okayama Prefecture, which is occupied by Lower Carboniferous to Middle Permian Ko-yama Limestone Group (Yokoyama et al., 1979), Permian Yoshii Group (Sano et al., 1987) and Triassic Nariwa Group (Tera-oka, 1959). The Nariwa Group unconformably covers the Paleozoic successions (Otoh, 1985). These succes-sions belong to the Akiyoshi Belt. The Ko-yama Limestone Group is composed mainly of massive limestone, with basic volcanic rocks, acidic tuff and chert. The group was dated by foraminifer and fusu-linid as Lower Carboniferous to Middle Permian (Yo-koyama et al., 1979).  相似文献   
94.
The Carboniferous conodont faunal succession of the lower part of Ko-yama Limestone Group was studied. The confirmed upper Visean–lower Moscovian lithostratigraphy of the group is characterized by the clastic carbonates with common association of the basaltic pyroclastics and some intercalation of spicular chert beds. The faunal succession of Gnathodus semiglaber (upper Visean), Gnathodus praebilineatus – Lochriea multinodosa (upper Visean), Lochriea ziegleri – Gnathodus girtyi girtyi s.l. (lower Serpukhovian), Neoganthodus symmetricus – Idiognathodus primulus (middle – upper Bashkirian), and Idiognathoides convexus – Gondolella clarki (lower Moscovian) faunas, appears in concordance with the lithostratigraphic order. The faunas are correlative with those from the conodont zones of the Hina, Atetsu, Akiyoshi and Omi limestone groups in the Akiyoshi Belt. The Visean/Serpukhovian boundary of the section was recognized by the FAD of Lochriea ziegleri.  相似文献   
95.
Quantitative determination of the degree of chemical weathering of rocks is a fundamental task in environmental and engineering geology, and many weathering indices based on whole-rock chemistry have been proposed. However, most classical indices are of limited application to granitoids in a wide area, because these lithotypes generally exhibit wide chemical variation arising from their petrogenesis. The chemical evolution produced during rock weathering, therefore, overprints pre-existing magmatic chemical variation. This problem can cause many classical weathering indices to yield misleading results. This study proposes a method that compensates for the influence of petrogenesis on calculation of the weathering index. The method is based on a bivariate plot of the magmatic chemical variation (MCV) in granitoids, and the degree of chemical weathering (DCW). The MCV axis must be based on an element that reflects magmatic processes and is also relatively immobile during rock weathering. In this study TiO2 contents are utilized for the MCV. The DCW axis is fundamentally defined by the ratios of more-mobile to less-mobile elements during weathering, and hence many classical indices can be applied. The improved value of the degree of chemical weathering (DCWi) for a weathered rock is derived by:
DCWi=s×(MCVCV-MCV1)+DCW1DCWi=s×(MCVCV-MCV1)+DCW1
where MCV1 is the measured composition (e.g. TiO2 content) of the weathered rock. DCW1 denotes the ratios of more-mobile to less-mobile elements of the weathered rock. The “s” parameter is the slope of the least square linear regression for fresh granitoids in the MCV–DCW relationship. MCVCV is a correction factor which is given by the average point on the MCV axis (e.g. average TiO2) of the fresh rocks. This method is useful for evaluating the degree of weathering of various granitoids, and enhances the practical application of many weathering indices.  相似文献   
96.
It is shown that the recently obtained Jordan-Brans-Dicke solutions by Chauvet and Guzmán (1986) are either inconsistent, or only special power-law solutions derived previously by Lorenz-Petzold in various papers.  相似文献   
97.
YASUO  IKEDA  KEISUKE  NAGAO  ROBERT J.  STERN  MAKOTO  YUASA & SALLY  NEWMAN 《Island Arc》1998,7(3):471-478
Noble gas concentrations and isotopic compositions have been measured in eight samples of pillow basalt glasses collected from seven different localities along 250 km of the Mariana Trough spreading and rifting axis. The samples have uniform and mid-ocean ridge basalt (MORB)-like 3He/4He values of 9–12 × 10–6 (6.4–8.6 times atmospheric) despite large variations in 4He. Concentrations of the noble gases Ne, Ar, Kr, and Xe show much smaller variations between samples, but larger variations in isotopic compositions of Ne, Ar, and Xe. Excess radiogenic 21Ne is observed in some samples. 40Ar/36Ar varies widely (atmospheric to 1880). Kr is atmospheric in composition for all samples. Some samples show a clear excess 129Xe, which is a well-known MORB signature. Isotopic compositions of the heavier noble gases (Ar, Kr, and Xe) in some samples, however, show more atmospheric components. These data reflect the interaction of a MORB-like magma with an atmospheric component such as seawater or of a depleted mantle source with a water-rich component that was probably derived from the subducting slab.  相似文献   
98.
99.
A surface buoy was moored from 20 April to 2 November 1988 at 28°48 N and 135°01 E where the water depth was 4900 m to measure temperature and velocity in the upper 150 m. The Typhoon 8824 passed at 0300 (JST) on 8 October about 50 km north to the mooring station with a maximum wind speed of 43.5 m s–1. The buoy was shifted about 30 km to southwest, and the instruments were damaged. The records of temperature at 0.5 m and velocity at 50 m were obtained. The inertial oscillation caused by the typhoon is described using the current record. The oscillation endured for about 20 days. Deep mixing and vertical, heart transport by the typhoon are discussed based on the data from the Ocean Data Buoy of the Japan Meteorological Agency moored at 29°N and 135°E.  相似文献   
100.
Radii and angular velocities in the motions of drifting buoys deployed in the Kuroshio are estimated by fitting circles to the trajectories of two drifting buoys, one with a drogue at 300 m depth and the other at 800 m depth. The buoys were deployed in the Kuroshio where it was flowing counter-clockwise around the large cold water mass south of Honshu. The same technique was applied to two drifting buoys with drogues at 300 m depth placed in the Kuroshio where it flowed clockwise around Oshima Island in Sagami Bay. The centrifugal forces were 7% and 6% as large as the Coriolis forces in the Kuroshio around the cold water mass, and they were –56% and –42% as large as the Coriolis forces in the current around the Oshima Island. The temperature gradient observed in the Oshima-West Channel suggested that the pressure gradient there was smaller due to the centrifugal force acting against the Coriolis force than the pressure gradient to be balanced with the Coriolis force.  相似文献   
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