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11.
根据对历史地震震中和山西断陷带内沉降中心的研究,发现该带内的强震震中与沉降中心有很好的对应关系。以现有的资料为基础,统计了各沉降中心内第四系与新生界的比值(Q/Kz)。结果表明,强震的发生与沉降中心的 Q/Kz值有一定的对应规律。根据这一结果,近一步讨论了512年7 1/2级地震的震中位置。  相似文献   
12.
王良玮  廖全荣 《冰川冻土》1993,15(4):590-594
MST-88型多路测温仪采用PC-1500(A)袖珍机作处理机,选用集成电路AD590作温度传感器,对10路温度参数轮流采集,对采集的数据进行了线性校正,以人-机对话的方式,使野外采集温度参数实现了自动巡测,打印,显示,外存及数据处理。  相似文献   
13.
李霓  Nicole  METRICH  樊祺诚 《岩石学报》2006,22(6):1465-1472
长白山天池火山在公元一千年左右曾发生过大规模喷发,其产物为大面积分布的灰白色碱流质浮岩和碎屑流,在其斑晶矿物橄榄石、钙铁辉石和碱性长石中均可见到熔融包裹体。在最主要的斑晶矿物——碱性长石中含有数量众多且个体也较大的熔融包裹体,多数含有一个以上的气泡,其中部分含有子晶,根据形貌特征的不同可分为截然不同的两组包裹体。这些熔融包裹体带有大量喷发前地下岩浆的信息,成为研究地下深部的岩浆在复杂的溢流-爆炸喷发中所发生变化的最好媒介。也是本文的研究对象,通过其中挥发份尤其是水的含量,可以推知天池火山发生大喷发的原因。经Nicolet Magna-IR 550红外光谱仪测定,这些熔融包裹体的含水量较高,达1.6%-3.6%,为当时天池火山发生了巨大规模爆炸喷发的原因提供了强有力的证据。但目前红外光谱仪的应用范围还比较有限,有待今后拓宽其应用领域。  相似文献   
14.
私人日记是重建历史时期高分辨率降水量序列的重要信息源.根据清代姚济所著的<己酉被水纪闻>中记录的上海(松江)1849年6月下旬至7月中旬逐日天气记录,辅以<清代长江流域西南国际河流洪涝档案史料>中的记载,确定了上海在大涝的1849年的入、出梅日期和梅雨期长度以及梅雨量,并重建了上海该年6月下旬、7月上旬、7月中旬以及整...  相似文献   
15.
H.A. Dal  S. Evren 《New Astronomy》2012,17(4):399-410
In this study, we present the unpublished flare data collected from 222 flares detected in the B band observations of five stars and the results derived by statistical analysis and modeling of these data. Six basic properties have been found with a statistical analysis method applied to all models and analyses for the flares detected in the B band observation of UV Ceti type stars. We have also compared the U and B bands with the analysis results. This comparison allowed us to evaluate the methods used in the analyses. The analyses provided the following results. (1) The flares were separated into two types, fast and slow flares. (2) The mean values of the equivalent durations of the slow and the fast flares differ by a factor of 16.2 ± 3.7. (3) Regardless of the total flare duration, the maximum flare energy can reach a different Plateau level for each star. (4) The Plateau values of EV Lac and EQ Peg are higher than the others. (5) The minimum values of the total flare duration increase toward the later spectral types. This value is called the Half-Life value in models. (6) Both the maximum flare rise times and the total flare duration obtained from the observed flares decrease toward the later spectral types.  相似文献   
16.
李凡  叶瑜  万金红 《古地理学报》2017,19(2):373-382
1920年华北五省旱灾被当时的报刊称为“四十年未有之奇荒”。依据《近代中国灾荒纪年续编(1919—1949)》中采用的关于此次大旱的各种原始记录,分3个社会层次6种类型统计分析了这些原始资料灾情记录的特点及差异,并探讨了不同类型史料用于旱灾重建的优势和局限性,得出以下主要结论: (1)记录内容方面,中央重点关注灾情最重县份,地方官方和组织统计更详尽,报刊记录具有非统计、重描述的特点;(2)统计信息数量方面,地方官方最大,中央次之,民间最少;(3)统计时间顺序方面,民间最早(报刊统计在时间上贡献最大),地方官方次之,中央最晚;(4)以《赈务通告》为代表的官方文书等资料的灾情统计信息丰富,有助于旱灾受灾区域重建;《近代中国灾荒纪年续编(1919—1949)》等整编资料多侧重对灾情的整理,关于此次旱灾其他影响和响应的记录还需其他史料的支持。  相似文献   
17.
The Hongtong earthquake occurring on 25 September 1303 in both Linfen Basin (LFB)and Taiyuan Basin (TYB)in Shanxi Graben is the first M8.0 earthquake based on the Chinese literature in China mainland, 392 years later, the Linfen M7.5 earthquake occurred on 18 May 1695 in Linfen Basin with its macro-epicenter distance of only 40km south of the Hongtong earthquake. Due to their close macro-epicenter distance and shortly interval of 392a, it attracted continuous attention to the geoscientists around Southern Shanxi Graben, southeastern Orods Plate. This paper combines the historical documents and interpreting the coseismic triggered disasters in study area. The results show that:1)the number of building damaged in the southern TYB and Lingshi Uplift (LSU)during 1303 Hongtong earthquake is similar to that of the LFB, indicating that the TYB and LSU maybe suffered the same or even worse earthquake disaster losses during the 1303 Hongtong earthquake. While the 1695 Linfen earthquake is confined within the LFB and south of Hongtong County; 2)More than 11 000 loess landslides were triggered by the 1303 Hongtong earthquake event between LFB and TYB, which is consistent with the literature records. We suggested the macro-epicenter of the 1303 Hongtong earthquake should move about 60km northward from the present location (36.3°N, 111.7°E)near Hongtong County to the new location (36.8°N, 111.7°E) between Huozhou City and Lingshi County, the new macro-epicenter location can reasonably explain the large-scale centralized earthquake-triggered landslides during the event. The landslides had aggravated the severity of the loss; 3)Our result helps to understand the spatial distribution of the two strong earthquakes and the relationship between them, especially the distribution map of earthquake-induced loess landslides by 1303 Hongtong earthquake extracted using the Google Earth images, which supports the amendment of the macro-epicenter.  相似文献   
18.
19.
The Eyjafjöll AD 2010 eruption is an extraordinary event in that it led to widespread and unprecedented disruption to air travel over Europe – a region generally considered to be free from the hazards associated with volcanic eruptions. Following the onset of the eruption, satellite imagery demonstrated the rapid transportation of ash by westerly winds over mainland Europe, eventually expanding to large swathes of the North Atlantic Ocean and the eastern seaboard of Canada. This small‐to‐intermediate size eruption and the dispersal pattern observed are not particularly unusual for Icelandic eruptions within a longer‐term perspective. Indeed, the Eyjafjöll eruption is a relatively modest eruption in comparison to some of the 20 most voluminous eruptions that have deposited cryptotephra in sedimentary archives in mainland Europe, such as the mid Younger Dryas Vedde Ash and the mid Holocene Hekla 4 tephra. The 2010 eruption, however, highlights the critical role that weather patterns play in the distribution of a relatively small amount of ash and also highlights the spatially complex dispersal trajectories of tephra in the atmosphere. Whether or not the preservation of the Eyjafjöll 2010 tephra in European proxy archives will correspond to the extensive distributions mapped in the atmosphere remains to be seen. The Eyjafjöll 2010 event highlights our increased vulnerability to natural hazards rather than the unparalleled explosivity of the event. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
20.
十六位模数转换器AD7705及其应用   总被引:12,自引:0,他引:12  
AD7705是AD公司最近推出的十六位模数转换器。我们主要介绍了它的功能和特点,给出了基于AD7705实际应用的硬件、软件设计方法,以及部分程序源代码,总结了实际应用中必须注意的几个技术问题。  相似文献   
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