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421.
我国突发公共事件应急管理宣传教育工作日益受到重视,但目前仍处于相对落后的水平,比如地震。主要表现为:应急管理的宣传教育流于宣传,教育基本空白;应急管理的宣传教育体系尚不完善、制度尚不健全;高质量的应急宣传教育门户网站尚未建立等。针对存在的这些问题,以浙江省为例,提出今后改进地震应急管理宣传教育工作的一些建议和对策。 相似文献
422.
“十五”网络项目中测震台站CDMA数据传输方式浅析 总被引:1,自引:1,他引:0
中国数字地震观测网络项目建设的一个重要特点是"网络到台站,IP到仪器",从台站数据的采集到数据传输,台网中心数据的接收与实时处理,全部建立在网络化的平台上.因此,保证数据传输的连续性是一个重要的前提,本文从CDMA数据传输方式的特点出发,详细分析了数字地震项目建设过程中测震台网试运行的数据特点,研究表明:测震台站CDMA数据传输模式的连续率较低,在条件许可的情况下,地震数据的传输应尽量采用专用信道. 相似文献
423.
粤北存在早侏罗世的岩浆活动——来自霞岚杂岩SHRIMP锆石U-Pb年代学的证据 总被引:7,自引:0,他引:7
报道了粤北梅州地区霞岚杂岩的SHRIMP锆石U-Pb年龄,花岗岩(196±2)Ma,辉长岩(195±1)Ma,为中国东南部缺少200~180Ma期间的岩浆岩报道增添了新资料,又表明了滨太平洋构造域至少在195Ma左右已经开始作用于中国东南部.野外揭露的新鲜露头上,辉长岩与花岗岩之间有岩浆部分混合作用现象.辉长岩局部发育20~30cm的细粒边,从辉长岩往花岗岩方向逐渐变细;花岗岩中发育大量暗色细粒-微粒闪长质岩浆包体,形态多样、大小不一,边部有暗色矿物集中现象,部分界线呈截然、模糊或过渡关系;包体中出现针状磷灰石;辉长岩类与花岗质岩石的稀土配分模式基本一致,其微量元素特征也具有明显的一致性;二者年龄十分接近,且基性岩略晚于花岗岩形成.这些特征均表明,早侏罗世基性岩浆注入引起了深部陆壳物质的熔融,并形成了酸性岩浆,然后二者发生混合产生了霞岚杂岩. 相似文献
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425.
Mauro A. Di Vito Elena Zanella Lucia Gurioli Roberto Lanza Roberto Sulpizio Jim Bishop Evdokia Tema Giuliana Boenzi Elena Laforgia 《Earth and Planetary Science Letters》2009,277(3-4):408-421
Public works in progress in the Campanian plain north of Somma-Vesuvius recently encountered the remains of a prehistoric settlement close to the town of Afragola. Rescue excavations brought to light a Bronze Age village partially destroyed and buried by pyroclastic density currents (PDCs) of the Vesuvian Pomici di Avellino eruption (3.8 14C ka BP) and subsequently sealed by alluvial deposits. Volcanological and rock-magnetic investigations supplemented the excavations.Careful comparison between volcanological and archaeological stratigraphies led to an understanding of the timing of the damage the buildings suffered when they were struck by a series of PDCs. The first engulfed the village, located some 14 km to the north of the inferred vent, and penetrated into the dwellings without causing major damage. The buildings were able to withstand the weak dynamic pressure of the currents and deviate their path, as shown by the magnetic fabric analyses. Some later collapsed under the load of the deposits piled up by successive currents. Stepwise demagnetization of the thermal remanent magnetization (TRM) carried by potsherds embedded in the deposits yields deposition temperatures in the order of 260–320 °C, fully consistent with those derived from pottery and lithic fragments from other distal and proximal sites. The fairly uniform temperature of the deposits is here ascribed to the lack of pervasive air entrainment into the currents. This, in turn, resulted from the lack of major topographical obstacles along the flat plain.The coupling of structural damage and sedimentological analyses indicates that the currents were not destructive in the Afragola area, but TRM data indicate they were still hot enough to cause death or severe injury to humans and animals. The successful escape of the entire population is apparent from the lack of human remains and from thousands of human footprints on the surface of the deposits left by the first PDCs. People were thus able to walk barefoot across the already emplaced deposits and escape the subsequent PDCs. The rapid cooling of the deposits was probably due to both their thinness and heat dissipation due to condensation of water vapour released in the mixture by magma–water interaction. 相似文献
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428.
任何无线电通信设备都是通过天线发射电波来传送信息的,因而,它在无线电通信 中占有极其重要的地位.笔者在本文中结合实际工作中的体会讨论了短波天线的类型和基本 特性,并提出了地震通信中常用短波天线的设计方法和架设要求. 相似文献
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430.
Tissue distribution of metals in striped dolphins (Stenella coeruleoalba) from the Apulian coasts, southern Italy. 总被引:4,自引:0,他引:4
Tissue distributions of metals (mercury, lead, cadmium, zinc, copper, iron, manganese) were determined in six specimens of striped dolphins (Stenella coeruleoalba, Meyen) stranded on the Apulian coasts (Southern Italy) between February and June 1987. Methyl mercury and selenium were also determined in the liver samples. The liver accumulated the highest concentrations of metals, except for cadmium and chromium. Metal levels were higher than those found in dolphins living in the Atlantic, but lower than those recorded in the same species from the French Mediterranean coasts. Necroscopic surveys found that all specimens were affected by haemorrhagic gastritis, but the cause was not clear. While it was not possible to related the death of dolphins to a specific cause, or to contaminants, the accumulation of metals is likely to contribute to the health of the organism and represents a risk factor for dolphins. 相似文献