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101.
Based on the Monte Carlo simulations we have studied the performance of the HEGRA system of imaging air erenkov telescopes (IACTs) in its present configuration of 4 IACTs as well as in its future final configuration of 5 IACTs. Here we present the results on the basic characteristics of the IACT system which are used in the standard data analysis procedure, i.e., the collection areas, the detection rates, the angular resolution, the energy resolution, and the γ/hadron-separation efficiency. By comparing several key Monte Carlo predictions with experimental results it is possible to check the accuracy of the simulations. The Monte Carlo results concerning hadron-nuclear showers are tested with the recorded cosmic ray events and the results concerning photon-induced showers are tested with a large data sample of γ-rays observed from BL Lac object Mkn 501 during its high flaring activity in 1997. Summarizing the simulations and current observations we give the basic recommendations of using the instrument and the major values of its sensitivity.  相似文献   
102.
处于印度大陆与亚洲大陆主碰撞带北东侧的兰坪盆地西缘的金满铜矿床,产于中生代陆相沉积砂岩、泥岩中,以其属新类型陆相喷流铜矿床而引起人们的关注。关于其成矿时代至今仍然存在争论。采用常规^40Ar/^39Ar阶段升温测年法对金满铜矿床主矿体旁侧的含铜热液蚀变矿物绢云母进行了测试,获得3组视平均年龄分别为88Ma、67Ma、37Ma。结合兰坪盆地区域地质成矿背景,认为金满铜矿成矿经历了早期67Ma的成矿作用和晚期37Ma的成矿叠加作用,后者代表了金满铜矿的主要形成年龄。金满铜矿床的2期成矿年龄可能是印~藏碰撞(古新世)和走滑~拉分(始新世)等重大地质构造事件在矿床中留下的同位素年龄信息.暗示着古新世时期的构造作用和始新世时期的构造-岩浆-成矿活动对兰坪盆地的作用。  相似文献   
103.
This study investigates the origin and regional tectonic implications of high-altitude Plio (?)–Quaternary fluvial deposits developed over the Bozdağ horst which is an important structural element within the horst–graben system of western Anatolia, Turkey.A total of 23 deposits occur near the modern drainage divide comprising fluvial to occasionally lacustrine deposits. The deposits are all elongated in N–S direction with a width / length ratio of 1 / 10. The largest of them is of 13 km in length with a maximum observable thickness of about 100–110 m. Morphological, lithological, deformational characteristics of these deposits and the drainage system of the area all suggest that the deposits were formed due to uplift and southward tilting of the Bozdağ horst. This tilting which is estimated as 1.2° to 2.2° caused accumulation of the stream load along channels flowing from south to north. All the deposits were later dissected by the same streams with the exception of one deposit which still preserves its original lake form. These deposits are of Quaternary age, which corresponds to the latest N–S directed extensional tectonic phase in the region.  相似文献   
104.
随着国土资源信息化建设的快速发展,各地积累了大量的土地利用数据及其变更数据,对这些海量数据的管理和使用,使得多源异构土地利用数据的集成成为当务之急。本文结合建库工作实际,简要介绍了多源异构土地利用数据存在的问题、整合建库的技术方案以及质量控制方案。  相似文献   
105.
本文着重介绍了成都市的地震监测工作状况。在“九五”、“十五”期间,成都市加大了对地震监测基础设施建设的投入,先后建成了成都市数字遥测地震台网(含一期工程、二期工程)和成都市数字电磁波观测台网,改造了成都市地震监测中心。根据成都市现有地震监(观)测能力,“十一五”期间,将继续加强成都市的地震监(观)测工作,从防震减灾的角度提升成都市的综合竞争力。  相似文献   
106.
最近国际上土动力学和岩土地震工程方面召开了两次重大学术会议,即2004年1月在美国Berkeley召开的第11届国际土动力学和地震工程学术会议(11thSDEE)以及和2004年8月在加拿大温哥华召开的第13届世界地震工程大会(13thWCEE),对这两次会议中有关砂土液化方面的研究进行综述,力求反映液化研究方面的最新研究进展和发展趋势。  相似文献   
107.
第29届IASPEI大会于1997年8月18~28日在希腊塞萨洛尼基举行,来自世界各地的约1000名科学家出席了本届大会。该文较详细地介绍了本届大会中有关“岩石圈结构、动力学过程和各向异性”专题(S11)的学术交流情况及各国学者在该专题的研究方面所取得的进展。  相似文献   
108.
Neogene Yamadağı volcanic rocks consist of basaltic trachyandesite, trachyandesite, andesite, and dacite. The major- and trace-element chemistry indicates that the lavas are dominantly calc-alkaline and mildly alkaline in character, sodic in nature, and intermediate to acidic in composition. REE and trace-element patterns of volcanic rocks are similar to those typical of within plate magmatics. Volcanic rocks have low 87Sr/86Sr (0.70389–0.70633) and high 143Nd/144Nd ratios (0.51267–0.51276) and mostly plot within the mantle array of the isotope ratio diagram. The linear correlations among 87Sr/86Sr143Nd/144Nd, SiO287Sr/86Sr and SiO2143Nd/144Nd isotope ratios in the volcanics suggest that fractional crystallization combined with minor assimilation was an important process within the collision zone.  相似文献   
109.
混合表面活性剂存在下锰的高灵敏显色反应研究   总被引:2,自引:0,他引:2  
尹家元  杨光宇 《岩矿测试》1998,17(4):282-284
研究了碱性介质中,Mn(Ⅱ)被空气氧化生成H2MnO3,然后在H3PO4介质中,Cu(Ⅱ)和阳离子型有机相/水相微乳液(CTMAB/戊醇/正庚烷/水)的存在下,Mn(Ⅳ)与二安替比林对乙氧基苯基甲烷(DApEM)生成橙色产物,λmax为450nm,ε=1.95×105L·mol-1·cm-1。Mn(Ⅱ)的质量浓度在0~320μg/L内符合比尔定律。方法用于合金中锰的测定,结果与标准值符合,5次测定结果的RSD<3%。  相似文献   
110.
The Netherlands is one of the most secularized countries in the western world. The aim of this paper is to put the secularization process in both historical and geographical perspective. As a mass process secularization started in the last quarter of the nineteenth century and accelerated from the sixties of this century onwards. The first concentrations of non-denominationalism could be found in the (Protestant) countryside of Friesland and Groningen as a consequence of profound social cleavages. Then, the big cities in the west took part in the process and more recently even the Catholic areas were affected due to the cultural revolution of the sixties and early seventies. Two counterforces were analysed: a religious revival within the Protestant community and the increasing proportion of Muslims and Hindus as a consequence of immigration and high fertility levels. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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