地球物理勘探用高精度隔离放大器

地球物理勘探在野外进行,测量的电信号振幅范围为n×100 uV～ n×1 V, 对电信号测量精度要求优于0.1%.这就要求相应的隔离放大器增益范围大,档差小, 温漂小.为了满足上述要求,设计的精密隔离放大器由高线性度高精度器件-隔离放大芯片AD202-组成隔离级,3个零漂移运放LT1250组成3级9档放大级,档差为10 dB,增益从0～ 90 dB可控.实际电路的测试结果表明: 基于AD202和LT1250设计的隔离放大器的最大非线性误差为0.23%,19小时内的漂移为27 uV,达到了设计要求.     

长白山火山公元1199～1201年喷发的历史记录

长白山天池火山是世界著名的火山之一,是我国规模最大、最具有潜在喷发危险的一座近代活动火山。目前,国内外许多火山学者为了研究天池火山最近一次大喷发年代问题,做了大量工作,并取得了一些年代资料,但一直没取得有关这次大喷发历史记载的证实。笔者等再次收集和查阅了一亿七千万字的文史古籍资料,通过整理、筛选、考证、对比和分析处理, 发现了长白山天池火山,于公元1199～1201年一次大喷发的历史记录。这对于长白山天池火山未来喷发危险性的研究具有重要的意义。     

山西历史强震震中和沉降中心的关系

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。     

Along-Channel Winds in Howe Sound: Climatological Analysis and Case Studies

This paper examines along-channel winds within Howe Sound, British Columbia, Canada, that occur from both the interior plateau out toward the coast as outflows and from the coast inland as inflows. First, the relationships between along-channel winds and pressure, temperature, and humidity are explored in Howe Sound–Cheakamus Valley. The pressure gradients between Pam Rocks and Squamish and Pam Rocks and Pemberton have the strongest correlations with outflow strength and that between Pam Rocks and Squamish has the strongest correlation with inflow strength. Outflows (inflows) have lower (higher) temperatures and dew point temperatures, except for the inflows in summer, which have lower dewpoint temperatures than the overall mean. Second, two case studies of outflow events are presented and described during the period of intensive observations prior to and during the Vancouver 2010 Winter Olympics. The January 2010 outflow event is caused by a zone of strong across-barrier mean sea level pressure gradient. The pressure gradient is formed behind an Arctic front that moved southward across Howe Sound. The February 2010 outflow event is caused by an approaching sea level low pressure centre from the Pacific that formed a northeast–southwest mean sea level pressure gradient across southern British Columbia. In the January case, the outflow layer is about 1.5?km deep, while it is shallower in the February case. Only the January outflow case exhibits hydraulic behaviour.     

珠江三角洲地区SO2浓度卫星遥感长时间序列监测

利用卫星OMI(Ozone Monitoring Instrument)数据获得的长时间序列SO₂浓度,分析广州亚运会从申办到成功举办期间珠江三角洲地区近地面SO₂浓度的变化过程,以及亚运会举办期间珠江三角洲SO₂浓度分布状况。结果表明OMI能够反映近地表的SO₂浓度变化趋势,广州亚运会从申办到成功举办期间珠江三角洲地区近地面SO₂浓度表现出明显的季节变化,且亚运会期间该地区近地面SO₂浓度比以往年同期要低,说明珠江三角洲地区联动的空气质量保障措施明显降低了该地区近地面的SO₂浓度。     

MST—88型多路测温仪

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。     

长白山天池火山千年大喷发岩浆含水量研究——熔融包裹体含水量的红外光谱测试

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。     

NEW EVIDENCES FOR AMENDMENT OF MACRO-EPICENTER LOCATION OF 1303AD HONGTONG EARTHQUAKE

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.     

基于《己酉被水纪闻》重建1849年上海梅雨期及其降水量

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...     

西南地区冬季气温和降水的时空变化

In recent years,the socio-economic impacts of winter extreme climate events have underscored the importance of winter climate anomalies in Southwest China (SWC).The spatio-temporal variability of surface air temperature (SAT) and precipitation in SWC and their possible causes have been investigated in this paper based on observational data from 1961 to 2010.The results indicate that SAT anomalies in SWC have two dominate modes,one is homogenous,and the other a zonal dipole.The former is caused by the anomalies of East Asian winter monsoon;the latter arises from the anomalies of both subtropical west Pacific high and regional cold air in lower troposphere.The most dominant mode of precipitation anomalies in SWC is homogenous and it has a high correlation with northern hemisphere annular mode (NAM,AO).Neither NAM nor ENSO has significant impacts on SAT in SWC.The anomalies of NAM are associated with the anomalies of tropical circulations,and there-fore precipitation over the SWC.When NAM is in positive (negative) phase,the winter pre-cipitation is more (less) than normal in SWC.Winter precipitation increase over the whole SWC is associated with the El Nino.However,during La Nina winter,the pattern is not uni-form.There is an increase in precipitation over the central parts and a decrease in western and eastern parts of SWC.The severe drought in SWC in winter 2010 is more likely caused by anomalies of NAM,not El Nino.