Mechanism Study of Transport and Distributions of Trace Metals in the Bohai Bay,China     

Li  Yuan-yi  Feng  Huan  Yuan  De-kui  Guo  Lei  Mu  Di 《中国海洋工程》2019,33(1):73-85

This study shows that there are two regions with high trace metal concentrations in the Bohai Bay, China. The numerical hydrodynamic model coupled with geochemical analysis was applied to understand the mass transport and sedimentation in the bay. The modeling results show that the two regions are located within the residual current vortexes. Results from the particle-tracking model indicate that the trace metals released from the land sources enter the regions and take a relatively long residence time in the vortexes. The sediment radionuclide data indicates that the two regions experienced continuous and high sedimentation, and trace metals are prone to deposit in the regions. The correlations among trace metals, residual currents and radionuclides data suggest that the tides are the governing factor controlling the distributions of the trace metals in the bay. The consistence among these results also supports the reliabilities of the numerical simulation results of water and trace metal transport in this study.  相似文献   

日本南海海槽地震海啸对我国东海沿岸影响     

闪迪  王培涛  任智源  孙立宁  赵联大  范婷婷 《海洋与湖沼》2018,49(6):1151-1158

本文利用数值模拟技术重现了1707年宝永地震海啸的传播过程,定量分析了我国东海沿岸海啸时空分布特征。计算结果表明,地震发生2.5小时后海啸波传至东海陆架,震后6小时浙江沿海地区遭到海啸的袭击,沿岸最大海啸波高为0.8米。通过海啸波在东海大陆架传播时海底地形与波幅的关系,研究分析了东海陆架缓变地形下海啸放大效应,为及时判断沿海可能的海啸强度和受灾程度提供了便捷的估算方法。此外,本文还评估了南海海槽发生极端地震时,中国东海沿岸的海啸危险性,为东海区域针对日本南海海槽进行海啸预警和减灾评估提供定量科学的参考。  相似文献   

The macrozoobenthos of the Karavasta lagoon system (Albania): local assemblages and geographical comparisons     

Carlotta Nonnis Marzano  Maria Flavia Gravina  Alessandra Fianchini  Giuseppe Portacci  Myriam Gherardi  Angelo Tursi  Giuseppe Corriero 《Marine Ecology》2010,31(4):622-632

The macrozoobenthic assemblage from the Karavasta lagoon system, the main wetland of Albania, was studied on soft bottoms and artificial hard substrates. Three different communities were identified: the typical ‘brackish‐water community’, an ‘outlet community’ dominated by filter‐feeders, and a typical ‘marine community’, inhabiting fine sandy bottoms, where polychaetes are dominant, together with a few species of tunicates and bivalves, which colonize hard substrates. The occurrence of build‐ups of the bryozoan Conopeum seurati, settled on the upper portion of long submerged wooden poles, was the main feature of faunistic interest. The faunistic affinity between the zoobenthic assemblage recorded in the hyperhaline lagoon of Karavasta and the assemblages from two Italian lagoons, the brackish Lake of Lesina and the euhaline Lake of Fogliano, was considered according to the different hydrological conditions and the geographical location. Hydrological confinement and salinity were likely to be the leading factors influencing the benthic community composition in the Karavasta wetland area. Therefore, on a vaster spatial scale, the isolation and geographical proximity of the ecosystems and colonizing ability and dispersal changes of the species appear to be the main factors liable to produce faunal variations.  相似文献   

The ARIEL Instrument Control Unit design     

M. Focardi  E. Pace  M. Farina  A. M. Di Giorgio  J. Colomé Ferrer  I. Ribas  C. Sierra Roig  L. Gesa Bote  J. C. Morales  J. Amiaux  C. Cara  J. L. Augurés  E. Pascale  G. Morgante  V. Da Deppo  M. Pancrazzi  V. Noce  S. Pezzuto  M. Frericks  F. Zwart  G. Bishop  K. Middleton  P. Eccleston  G. Micela  G. Tinetti 《Experimental Astronomy》2018,45(1):1-20

In this paper we present the electromagnetic modeling and beam pattern measurements of a 16-elements ultra wideband sparse random test array for the low frequency instrument of the Square Kilometer Array telescope. We discuss the importance of a small array test platform for the development of technologies and techniques towards the final telescope, highlighting the most relevant aspects of its design. We also describe the electromagnetic simulations and modeling work as well as the embedded-element and array pattern measurements using an Unmanned Aerial Vehicle system. The latter are helpful both for the validation of the models and the design as well as for the future instrumental calibration of the telescope thanks to the stable, accurate and strong radio frequency signal transmitted by the UAV. At this stage of the design, these measurements have shown a general agreement between experimental results and numerical data and have revealed the localized effect of un-calibrated cable lengths in the inner side-lobes of the array pattern.  相似文献   

Assessment of Planetary Boundary-Layer Schemes in the Weather Research and Forecasting Mesoscale Model Using MATERHORN Field Data   总被引：1，自引：0，他引：1  

Reneta Dimitrova  Zachariah Silver  Tamas Zsedrovits  Christopher M. Hocut  Laura S. Leo  Silvana Di Sabatino  Harindra J. S. Fernando 《Boundary-Layer Meteorology》2016,159(3):589-609

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Exceptional floods on a developed river: case study for the Bistrita River from the Eastern Carpathians (Romania)     

Gianina Maria Cojoc  Gheorghe Romanescu  Alina Tirnovan 《Natural Hazards》2015,77(3):1421-1451

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Severity and exposure associated with tsunami actions in urban waterfronts: the case of Lisbon,Portugal     

Daniel A. S. Conde  Maria J. Telhado  Maria A. Viana Baptista  Rui M. L. Ferreira 《Natural Hazards》2015,79(3):2125-2144

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Reply to comment on ‘Insights from the Mw 6.3 2009 L’Aquila earthquake (Central Apennines) – unveiling new seismogenic sources through their surface signatures: the adjacent San Pio Fault’     

Daniela Di Bucci  Paola Vannoli  Pierfrancesco Burrato  Umberto Fracassi  Gianluca Valensise 《地学学报》2011,23(6):421-423

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Analytical solution for 1D consolidation under haversine cyclic loading     

Sabah S. Razouki  Paul Bonnier  Maria Datcheva  Tom Schanz 《国际地质力学数值与分析法杂志》2013,37(14):2367-2372

Presented and discussed in this paper is an exact analytical solution of the nonhomogeneous partial differential equation governing the conventional one‐dimensional consolidation under haversine repeated loading. The derived analytical solution to the 1D consolidation equation is compared with the numerical solution of the same consolidation problem via FEM. The series solution takes into account the frequency of repeated loading through a dimensionless time factor T₀. The paper reveals that an increase in the frequency of imposed repeated haversine loading (a decrease in period of repeated loading) causes an increase in the number of cycles required to achieve the steady state, whereas the effect of frequency on the maximum excess pore water pressure at the bottom of a clay layer with permeable top and impermeable bottom for the range of frequencies studied is generally insignificant. The effective stress at the bottom of the clay deposit with permeable top and impermeable bottom increases with time but with some fluctuations without changing the sign. These fluctuations become more pronounced for increasing values of T₀. An increase in T₀ also causes an increase in maximum effective stress. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

Search for radio pulsations in four anomalous X-ray pulsars and discovery of two new pulsars     

Marta Burgay  Nanda Rea  GianLuca Israel  Andrea Possenti  Luciano Burderi  Tiziana Di Salvo  Nichi D’Amico  Luigi Stella  Elisa Nichelli 《Astrophysics and Space Science》2007,308(1-4):531-534

We have performed deep searches for radio pulsations from four southern anomalous X-ray pulsars (AXPs) to investigate their physical nature in comparison with the rotation powered pulsars. The data were acquired using the Parkes radio telescope with the 1.4 GHz multibeam receiver. No pulsed emission with periodicity matching the X-ray ephemeris have been found in the observed targets down to a limit of ∼0.1 mJy. A blind search has also been performed on all the 13 beams of the multibeam receiver (the central beam being pointed on the target AXP), leading to the serendipitous discovery of two new radio pulsars and to the further detection of 18 pulsars. Also a search for single dispersed pulses has been performed in the aim to detect signals similar to those of the recently discovered rotating radio transients.   相似文献