河西走廊东部冬季沙尘暴的典型个例及气候特征分析

应用1971—2016年河西走廊东部代表站的地面观测资料、NCEP 2.5°×2.5°月均地面至300 hPa高空资料,2006—2016年民勤逐日07和19时每隔10 m加密高空资料,分析了近45年河西走廊东部冬季沙尘暴天气的年际变化特征。同时选取2016年11月两次沙尘暴天气过程从天气学成因、物理量场及近地面边界层特征等方面进行了诊断分析。结果表明:近45年河西走廊东部冬季沙尘暴日数呈减少趋势,产生大风沙尘天气的主要原因不仅与大型冷暖空气强度及环流形势有关,还与冷锋过境时间、日变化、近地层风速和干湿程度关系密切。夜间至早晨近地面逆温厚且强,大气层结稳定,削弱沙暴强度,而午后到傍晚,逆温薄而弱,大气层结不稳定性强,加强了动量下传和风速,增强沙暴强度。近地层越干,风速越大,沙暴越强。     

Variations in annual winter mean temperature in South China since 1736

Modern meteorological observations in South China from 1960 to 2009 show a strong correlation between winter temperatures and two snowfall parameters, the southern boundary of the snow and the number of snowy days. Based on this relationship, the variation in annual winter mean temperature in South China from 1736 to 2009 was reconstructed using data acquired from Chinese historical documents dating from the Qing dynasty, such as memos and local gazettes. The reconstructed time series were used to analyse variations in winter temperature in South China. Significant interannual and interdecadal changes were found. The maximum temperature difference between neighbouring years was 3.1 °C for 1958–2009 and 3.0 °C for 1736–1957, whereas the maximum temperature difference between adjacent decades was 0.8 °C for the 1960s–2000s and 0.6 °C for the 1740s–1950s. The 2000s was the warmest decade; the mean temperature was 1.6 °C higher than that of the 1870s, which was the coldest decade between the 1740s and the 2000s. The mean winter temperature was warmer in the 18th and 20th centuries and coldest in the 19th century.     

Lateral dynamic response of a pipe pile in saturated soil layer

This paper presents an analytical solution for the lateral dynamic response of a pipe pile in a saturated soil layer. The wave propagations in the saturated soil and the pipe pile are simulated by Biot's three‐dimensional poroelastic theory and one‐dimensional elastic theory, respectively. The governing equations of soil are solved directly without introducing potential functions. The displacement response and dynamic impedances of the pipe pile are obtained based on the continuous conditions between the pipe pile and both the outer and inner soil. A comparison with an existing solution is performed to verify the proposed solution. Selected numerical results for the lateral dynamic responses and impedances of the pipe pile are presented to reveal the lateral vibration characteristics of the pile‐soil system. Copyright © 2015 John Wiley & Sons, Ltd.     

钴—5—Br—PADNm络合物的光度性质研究及其应用

本文研究了钴(Ⅱ)-5-Br-PADNm络合物的光度性质。在pH5.0缓冲溶液中,有TritonX-100存在时,Co~(2 )与5-Br-PADNm形成1:2红色络合物,λ_(max)为547nm,ε为1.35×10~5l·mol~(-1)·cm~(-1)。所提出的方法用于矿石及茶叶中Co的测定,得到满意结果。     

中国主要河流年径流序列随机变化基本规律的初步研究

本文以中国主要河流(100多条河流,177个站)年径流资料为基础,采用近代随机水文学方法,并结合年径流的成因分析,探讨了中国主要河流年径流序列的趋势性、近似周期性、相依性和持续性特点。还研究了它们的分区变化规律。     

Climatic study on the summer tropical easterly jet at 200 hPa

The low latitude easterlies at 200 hPa in summer (May-October) is analysed climatically during the 13-year period from 1968 to 1980, with a special emphasis on the relationship between the anomalous tropical easterly jet stream over South Asia and the low latitude atmospheric circulation, and also the summer monsoon precipitation in India. The compositing analysis shows that the tropical easterly jet stream over South Asia has five anomalous patterns at 200 hPa i.e. the western pattern, middle pattern, eastern pattern, two-branch pattern and multi-core pattern. Evidence has shown that the precipitaion in India anomalously increased during the anomalous period of the western pattern and the middle pattern, but reverse case is true in the eastern pattern. Some different anomalies of the precipitation in different area of India were found during the other two anomalous pattern.     

Medium-range oscillations in the summer tropical easterlies at 200 hPa

By the use of space-time spectral analysis and band-pass filter, some of the features of the medium-range Oscillations in the summer tropical easterlies (10oS-20o) at 200 hPa are investigated based on a two-year (1980 and 1982) wind (u, v) data set for the period from May to September. Space-time power spectral analysis shows that the total energy of the westward moving waves was the largest and that of the standing waves and eastward moving waves was relatively small in the 200 hPa easterlies; the total energy of the eastward moving waves was at minimum at 10oN. Three kind of the medium-range oscillations with about 50 day, 25 day and quasi-biweekly periods were found in the easterlies, which all show a remarkable interannual variation and latitudinal differences in these two years. The wave energy of zonal wind is mainly associated with the planetary waves (1-3), which all may make important contributions to the 50 day and 25 day oscillations in different years or different latitudes. The quasi-biweekly oscillation is mainly related to the synoptic waves (4-6). In equatorial region, the 50 day oscillation was dominant with a eastward phase propagation in 1982 while the dominant oscillation in 1980 was of 25day period with a westward phase propagations in 1980. Both of them are of the mode of zonal wavenumber 1. Strong westward 50 day oscillation was found in 10oN-20oN in these two years. Regular propagations of the meridional wind 50 day oscillation were also found in the easterlies.The 50 day and 25 day oscillation of zonal wind all demonstrate southward phase propagation over the region of the South Asia monsoon and northward phase propagation near interational date line, where are the climatic mean position of the tropical upper-tropospheric easterly jet and the tropical upper tropospheric trough (TUTT), respectively.     

微型活性碳柱富集比色法测定金

本文探讨了用微型活性碳柱富集痕量金的方法。研究了富集金和TMK—Au—Twee 85显色反应的条件,用本法测定了地质试样中痕量金,其测定限为2 ppbAu,本法操作简便、快速,灵敏度高,结果较为满意。     

5—10月全球热带和副热带200hPa多年平均环流的研究(一)——行星尺度环流系统

本文用近13年200hPa高空风资料得到了夏半年(5—10月)逐月平均全球热带风场,发现如下一些主要结果: (1)在亚洲地区对流层上部反气旋存在两个中心;一个在青藏高原上空;一个在伊朗和阿富汗地区。两者的演变不同。伊朗高压的北推和撤退都比青藏高原上的早。北美墨西哥高压的变化在时间上与伊朗高压很相似。 (2)北太平洋中部高空槽(TUTT)出现在5—10月,8月份最强,位置最北;北大西洋中部高空槽出现在5—9月,7—8月最强。 (3)南半球冬季有三个主要的长波脊和长波槽,分别位于大陆以西和以东海区。     

新疆特克斯-昭苏地震断层的发现及有关问题的讨论

1986年作者在特克斯-昭苏盆地首次发现长70公里、最大垂直和水平位移均达8米的地震断裂带和地震形变现象,并认为是1716年地震时形成的。地震断裂带的展布和运动方式,与科博河-昭管处断裂相一致。特克斯断裂带是一条复杂的断裂带,它由多条断裂组成。1716年地震表明该断裂带具有新的活动性