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161.
本文主要介绍模拟碰带记录地震仪MCD—3及其解调器CBY—2系列的一种行之有效的改进法。该方案配以IBM—PC/XT计算机硬软件,能实现宽频多道数字采集与处理。改装结果在工程地震方面获得广泛的应用,取得明显的经济效果。  相似文献   
162.
内蒙红花沟金矿床同位素地质特征及矿床成因探讨   总被引:4,自引:0,他引:4  
通过对红花沟金矿床主要岩类及金矿石的氧、氢、铅、钾-氩和铷锶同位素的测定,研究了该矿的同位素地球化学特征,探讨了成矿物质来源、成矿时代、成矿温度等矿床成因问题。认为成矿物质来自建平群变质岩,元古宙钾长花岗岩的成岩作用使金活化迁出而成矿。成矿热液以岩浆水为主,并有部分大气降水混入,成矿温度为250~350℃。  相似文献   
163.
天气概率预报的科学性及其应用前景   总被引:4,自引:0,他引:4       下载免费PDF全文
陆如华  裘国庆 《气象》1995,21(11):3-6
介绍了天气概率预报的科学性、对象、方法及应用前景,指出天然概率预报是我国天气预报技术的发展,它是适应社会需求,提高天气预报效益的重要手段。  相似文献   
164.
通过新建立的BiPO4转化法,笔者分析了白云鄂博矿区部分磷灰石的氧同位素组成,其变化范围为6.3‰~9.4‰,并通过与各种产状磷灰石及不同时代磷酸盐沉积的氧同位素对比、磷灰石形成温度的计算,以及磷灰石Sr-Pb同位素数据的分析,推断矿区磷灰石的形成可能与热水沉积作用有关。  相似文献   
165.
近年来湖南省在地勘行业管理上开展了法规法制建设、规划计划编制、勘查秩序维护、勘查成果管理、勘查外部环境改善等方面的工作,“八五”后3年继续开展法制建设、勘查登记管理、勘查成果管理、建立行业统计系统、做好服务协调工作,推广改革经验等。  相似文献   
166.
In situ measurements of stratospheric H2SO4 and HSO3vapors using passive chemical ionization mass spectrometry were made in October 1982 after the eruption of volcano El Chichon. Data were obtained between about 20 and 41 km showing [H2SO4 + HSO3] sum concentrations between about 104 and 2 × 105 cm?3 below 29 km and a steep rise above this altitude. Maximum [H2SO4 + HSO3] values of about 3 × 106 cm?3 are reached above 35 km.Partial [HSO3] concentrations increase above 34 km reaching about 4 × 105cm?3 around 40 km. From the measurements it is concluded that H2SO4 and probably HSO3photolysis have an important influence above 34 km leading to the observed increase of [HSO3] and a depletion of H2SO4vapor.It also seems that the data support the view of heterogeneous HSO3 removal. If correct, this would imply that stratospheric aerosols are formed primarily from HSO3 rather than H2SO4vapor.  相似文献   
167.
Radium-226 (226Ra) activities were measured in the surface water samples collected from the Arctic Ocean and the Bering Sea during the First Chinese National Arctic Research Expedition. The results showed that 226Ra concentrations in the surface water ranged from 0.28 to 1.56 Bq/m3 with an average of 0.76 Bq/m3 in the Arctic Ocean, and from 0.25 to 1.26 Bq/m3 with an average of 0.71 Bq/m3 in the Bering Sea. The values were obviously lower than those from open oceans in middle and low latitudes, indicating that the study area may be partly influenced by sea ice meltwater. In the Bering Sea, 226Ra in the surface water decreased northward, probably as a result of the exchange between the 226Ra-deficient sea ice meltwater and the 226Ra-rich Pacific water. In the Arctic Ocean, 226Ra in the surface water increased northward and eastward. This spatial distribution of 226Ra reflected the variation of the 226Ra-enriched river component in the water mass of the Arctic Ocean. The vertical profiles of 226Ra in the Canadian Basin showed a concentration maximum at 200 m, which could be attributed to the inputs of the Pacific water or/and the bottom shelf water with high 226Ra concentration. This conclusion was consistent with the results from 2H, 18O tracers.  相似文献   
168.
Ji  H.S.  Wang  H.  Spirock  T.J.  Qiu  J.  Yang  G.  Goode  P.R. 《Solar physics》2002,211(1-2):221-229
Using data obtained with the 20-cm H full-disk telescope at Big Bear Solar Observatory and Fexii 195 Å EIT on SOHO, we analyze a sudden disappearance event of a quiescent filament in detail. The filament was located along the common boundary of the active regions NOAA 9672 (S19 E13) and NOAA 9673 (N03 E18). The filament disappeared during a time interval between 17:59 UT and 19:47 UT on 22 October 2001 immediately after the onset of a major flare, which occurred in the active region NOAA 9672. At about 23:23 UT of the same day, the filament began to reappear in H and, after about 15 hours, the filament recovered to its steady state with its size being slightly smaller than that before its disappearance. This filament disappearance event belongs to the thermal type of sudden filament disappearances, which is caused by an input of additional heat. The heating mechanism that leads to sudden thermal disappearances of quiescent filaments is still not well understood. This simple event, due to the explicit cause and effect relationship between the flare and the disappearance of the filament, shows us that the flare triggered some kind of heating mechanism which continued several hours. The heat may come from the flare via heat conduction from its ribbon or from the excitation of dissipating Alfvén waves. However, from the data analysis, we conclude that the flare triggered an in-situ heating, which is likely caused by magnetic reconnection.  相似文献   
169.
提出一种以气象站点观测资料为基础,用G IS技术建立山地平均气温分布模型的方法。通过数字高程模型(DEM),获取地形数据,建立山地天文辐射模型。考虑海拔高度、地形等影响气温空间分布因子,建立山地气温分布模型。  相似文献   
170.
本文根据夏热冬暖地区的气候特点,针对目前建筑节能设计存在的薄弱环节,分析了建筑围护结构的构造措施及其热工性能,提出在节能设计中应注意的问题。  相似文献   
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