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41.
Aimed at promoting regional coalitions and expanding the approach to economic links, this paper puts forward some new concepts such as link intensity and receiving coefficient, expounds the indexes of quantitative analysis of economic links and establishes the quantitative-analysis model of economic links. With help of the model, this paper calculates the values of the link intensities between Su-Xi-Chang (Suzhou-Wuxi-Changzhou) region and Shanghai, and analyzes the regional difference of the economic links.  相似文献   
42.
Based on the Germany Koldwey Station's 1994-2003 conventional observation hourly data, this paper conducts a statistical analysis on the short-term climate characteristics for an arctic tundra region (Ny-(A)lesund island) where our first arctic expedition station (Huanghe Station) was located. Affected by the North Atlantic warming current, this area has a humid temperate climate, and the air temperature at Ny-(A)lesund rose above 0 ℃ even during deep winter season during our research period. The wind speed in this area was low and appeared most at southeast direction. We find that the temperature at Ny-(A)lesund rose in the faster rate (0.68 ℃/10 a) than those at the whole Arctic area. Compared with the floating ices where our expedition conducted in the Arctic, Ny-(A)lesund was warmer and more humid and had lower wind speed. Comparison of the near surface air temperature derived by NCEP/NCAR reanalysis to the conventional measurements conducted at the Koldwey site in Ny-(A)lesund area shows a good agreement for winter season and a significant difference for summer season.  相似文献   
43.
44.
Urban heat environmental quality(UHEQ) is affected by the interacting of weather condition and underlying surface framework of urban area .In the last two decades,many researchers from domestic and overseas have studied many problems at the aspect of urban heat environment such as urban heat islands ,urban air temperature and their rela-tion with urban land cover,city population,air pollution etc,In the recent years,Hangzhou,acting as a center city of Zhejiang Province in China,its urbanization quantum and quantity have both changed greatly,in particular ,representing as business affairs building,resident real property and all kins of specialty market having arisen in built-up zone,Based on Landsat TM images data in 1991 and 1999,urban underlying surface temperature value and Normalized Difference Vegetation Index (NDVI) were calculated using image interpreting and supervised classification technique by remote sensing software ERDAS image 8.4,The relation model between urban underlying surface temperature (UUST )and urban air temperature was setup according to the certain correlation patten .Reference to the relational standard of assessing human comfort and other meteorology data of Hangzhou City in summer,the spatial distribution characteristic and the spatial varia-tion degree of human comfort of heat environmental quality are estimated and mapped on a middle scale,that is ,in six districts of Hangzhou City .Then the paper reveals the main characteristic of spatial variation from 1991 to 1999.Lastly,the change mechanism is analyzed and discussed from the viewpoint of city planning,construction and environmental protec-tion.  相似文献   
45.
46.
We report observations by the Large Angle Spectrometric Coronagraph (LASCO) on the SOHO spacecraft of three coronal green-line transients that could be clearly associated with coronal mass ejections (CMEs) detected in Thomson-scattered white light. Two of these events, with speeds >25 km s-1, may be classified as ‘whip-like’ transients. They are associated with the core of the white-light CMEs, identified with erupting prominence material, rather than with the leading edge of the CMEs. The third green-line transient has a markedly different appearance and is more gradual than the other two, with a projected outward speed <10 km s-1. This event corresponds to the leading edge of a ‘streamer blowout’ type of CME. A dark void is left behind in the emission-line corona following each of the fast eruptions. Both fast emission-line transients start off as a loop structure rising up from close to the solar surface. We suggest that the driving mechanism for these events may be the emergence of new bipolar magnetic regions on the surface of the Sun, which destabilize the ambient corona and cause an eruption. The possible relationship of these events to recent X-ray observations of CMEs is briefly discussed. Supplementary material to this paper is available in electronic form at http://dx.doi.org/10.1023/A:1004981125702  相似文献   
47.
H. Wang  H. Zirin 《Solar physics》1987,110(2):281-293
We have measured the contrast of solar faculae near the limb on direct digital video images made with the 65 cm vacuum reflector at the Big Bear Solar Observatory. We used six broad band filters with different wavelengths from red to violet. The range of heliocentric angle covered in our measurements is 0.05 < = cos < 0.4 ( = 87°–66°). About 300 images were measured from observations made during the summers of 1983 and 1985. Over 20000 faculae were measured.By averaging the contrasts of faculae and plotting them vs heliocentric angle, we found that contrast increases monotonically towards the limb for the shorter wavelengths; for longer wavelengths, contrast has a tendency to peak around = 0.15, and then decrease towards the extreme limb. The contrast increases as wavelength decreases.  相似文献   
48.
In this paper, the neutrino mass has been determined from SN1987a observation in a manner that the simultaneity of neutrino emission is not regarded as the starting point, but is itself defined through the analysis by Monte-Carlo simulation. The result is that the neutrino mass lies in 3–4 eV, possiblym v 3.6 eV. Neutrino luminosity variation and neutrino spectrum are also obtained. Comparison with theories gives further support to the mass determination, and also predicts the mass of progenitor star of SN1987a to be in the range of 12–25M .The project supported by the National Natural Science Foundation of China.  相似文献   
49.
渭河盆地北缘断裂带活动特征的初步研究   总被引:8,自引:1,他引:7       下载免费PDF全文
本文从渭河盆地北缘断裂的形成和活动时代,活动特征等资料出发,结合北缘断裂带及整个盆地历史地震活动和新生界地层发育特征的综合分析,对北缘断裂带的活动期次,主要断层的运动幅度和滑动速率及其时空演变规律和机制等问题进行了探讨。文章指出,北缘断裂带的形成是一个由盆地中心向北逐渐扩展的过程,自上新世起,断层活动明显有东强西弱的变化特征,而且扩展方向也发生了偏转。这一转变及活动强度的东西差异与山西剪切带对渭河盆地的影响密切相关  相似文献   
50.
Trace and RE element geochemistry and genesis have been studied with respect to ferromanganese nodules from the sediments of the Pacific, Atlantic and Indian oceans.  相似文献   
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