HH24–26: structure,dynamics and chemistry     

A. G. Gibb  L. T. Little 《Astrophysics and Space Science》1995,224(1-2):467-468

New J=1-0 HCO⁺ and J=2-1 C¹⁸O observations of HH24–26 reveal striking differences between these and previous maps of higher-J transitions of HCO⁺ and CS. The high-J HCO⁺ and CS emission traces the densest portions of the cloud, while C¹⁸O traces the more tenuous envelope. This is also evident in the velocity structure. HCO⁺ and C¹⁸O appear to be depleted from the gas phase by amounts which vary with position.  相似文献   

中国东部第三系陆相沉积中的甲藻甾烷：海侵指相的标志物？   总被引：12，自引：0，他引：12  

侯读杰  张林晔 《地质论评》1997,43(5):524-528

通过对我国东部盆地洪泽凹陷和临清坳限德州凹陷第三系相沉积泥岩中生物标志物分析，检测到了丰富的甲藻甾烷异构体和２４－正丙基胆甾烷。结合它们的分布特征与产出的地层微体古生物资料，笔者推断它们可能是海侵作用的产物。  相似文献   

Luna24月岩样品中火成岩碎屑的岩石学及其成因探讨     

路凤香 Tayl.  LA 《地球科学》1990,15(6):617-627

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24位地震数据采集器中的数据处理     

王翠芳  邵玉平  宋澄 《国际地震动态》2007,(5):34-37

24位地震数据采集器中的数据处理过程是:地震计将感应到的地面运动信号转换成电压值输出给采集器,采集器将模拟电压信号进行滤波放大,再进行A/D转换成512KSPS的1位数据码流,该码流经DSP的两段滤波后得到COUNT值,DSP从RAM中取出COUNT值归一化后打包输出。  相似文献   

24位真彩色图像色彩的反转处理     

丛文卓刘刚  饶欣平 《测绘学院学报》2004,21(2):134-135

通过对24位真彩色BMP图像格式的分析，介绍一种图像线性变换函数，并提供了图像反转处理的方法及实例分析。  相似文献   

Geology and age model of the Lower Pleistocene Nojima,Ofuna, and Koshiba Formations of the middle Kazusa Group,a forearc basin‐fill sequence on the Miura Peninsula,the Pacific side of central Japan     

Atsushi Nozaki  Ryuichi Majima  Koji Kameo  Saburo Sakai  Atsuro Kouda  Shungo Kawagata  Hideki Wada  Hiroshi Kitazato 《Island Arc》2014,23(2):157-179

We present field and core observations, nannofossil biostratigraphy, and stable oxygen isotope fluctuations in foraminiferal tests to describe the geology and to construct an age model of the Lower Pleistocene Nojima, Ofuna, and Koshiba Formations (in ascending order) of the middle Kazusa Group, a forearc basin‐fill succession, exposed on the northern Miura Peninsula on the Pacific side of central Japan. In the study area, the Nojima Formation is composed of sandy mudstone and alternating sandy mudstone and mudstone, the Ofuna Formation of massive mudstone, and the Koshiba Formation of sandy mudstone, muddy sandstone, and sandstone. The Kazusa Group contains many tuff beds that are characteristic of forearc deposits. Thirty‐six of those tuff beds have characteristic lithologies and stratigraphic positions that allow them to be traced over considerable distances. Examination of calcareous nannofossils revealed three nannofossil datum planes in the sequences: datum 10 (first appearance of large Gephyrocapsa), datum 11 (first appearance of Gephyrocapsa oceanica), and datum 12 (first appearance of Gephyrocapsa caribbeanica). Stable oxygen isotope data from the tests of the planktonic foraminifer Globorotalia inflata extracted from cores were measured to identify the stratigraphic fluctuations of oxygen isotope ratios that are controlled by glacial–interglacial cycles. The observed fluctuations were assigned to marine isotope stages (MISs) 49–61 on the basis of correlations of the fluctuations with nannofossil datum planes. Using the age model obtained, we estimated the ages of 24 tuff beds. Among these, the SKT‐11 and SKT‐12 tuff beds have been correlated with the Kd25 and Kd24 tuff beds, respectively, of the Kiwada Formation on the Boso Peninsula. The Kd25 and Kd24 tuff beds are widely recognized in Pleistocene strata in Japan. We used our age model to date SKT‐11 at 1573 ka and SKT‐12 at 1543 ka.  相似文献   

Seasonal along-isobath geostrophic flows on the west Florida shelf with application to Karenia brevis red tide blooms in Florida's Big Bend     

Daniel F. Carlson  Allan J. Clarke 《Continental Shelf Research》2009

TOPEX/Poseidon/Jason1 (T/P/J) sea surface height (SSH) measurements along tracks 91 and 15, crossing the wide West Florida continental shelf (WFS), were used to estimate seasonal across-shelf SSH gradients. SSH gradients and the knowledge that geostrophic flow approximately follows the isobaths enable estimation of the seasonal along-isobath geostrophic flows. The calculated along-isobath geostrophic flows are southeastward from December to March and northwestward in June, August, and September. The along-isobath geostrophic component of the flow is most likely small during the remaining months and, thus, not discernable in T/P/J SSH measurements. In agreement with previous theoretical, modeling, and observational work, the mid-shelf seasonal surface flow appears to be driven largely by the seasonal along-shore wind stress. Theory for flow driven by seasonal heat flux suggests negligible flow near the surface and on the bulk of the shelf away from the shelf break.  相似文献   

高分辨低漂移的数据采集技术研究     

张俊  邹镇宇  薛兵 《地震地磁观测与研究》2011,32(5):104-108

对于测震观测,大动态和宽频带是当代最主要的技术特征,其关键设备是反馈地震计和24位数据采集器.通过引入调制解调技术来克服由于半导体器件低频噪声和环境温度变化引起的长周期漂移,提高长周期频段数据采集的技术水平.  相似文献   

Storms Generator Method That Preserves Their Historical Statistical Characteristics. Application To Mexico City Basin Daily Rainfall Fields     

R. Domínguez-Mora  M.L. Arganis-Juárez  A. Mendoza-Reséndiz  E. Carrizosa-Elizondo  B. EchavarrÍa-Soto 《Atmósfera》2013,26(1):27-43

A first procedure to generate synthetic storms, which preserves the statistical characteristics of the historical daily precipitation events registered in 49 stations located within the basin of Mexico City is presented. This procedure (a variation of the Svanidze method) implicitly supposes that the correlation between the maximum rainfall and its spatial distribution is meaningless. However, the obtained results did not validate that hypothesis. For this reason a second procedure was developed, which allows to consider the correlation between maximum rainfall and spatial distribution. This second procedure allowed reproducing the statistical characteristics of the daily rainfall for each station and also its spatial distribution, as shown in this work.  相似文献   

XMM–Newton observations of the ultra-compact binary RX J1914+24     

Gavin Ramsay  Pasi Hakala  Kinwah Wu  Mark Cropper  K. O. Mason  F. A. Córdova  W. Priedhorsky 《Monthly notices of the Royal Astronomical Society》2005,357(1):49-55

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