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Page DS Boehm PD Brown JS Neff JM Burns WA Bence AE 《Marine environmental research》2005,60(4):422-436
Polycyclic aromatic hydrocarbons (PAH) were measured in mussels (Mytilus trossulus) collected between 1990 and 2002 from 11 sites on the shores of Prince William Sound (PWS), Alaska, that were heavily oiled by the 1989 Exxon Valdez oil spill (EVOS). This study, utilizing the methods of the NOAA Status and Trends Mussel Watch Program, found that concentrations of PAH released from spill remnants have decreased dramatically with time and by 2002 were at or near the range of total PAH (TPAH) of 3-355 ng/g dry weight obtained for mussels from unoiled reference sites in PWS. Time-series TPAH data indicate a mean TPAH half-life in mussel tissues of 2.4 years with a range from 1.4 to 5.3, yielding an annual mean loss of bioaccumulated TPAH of 25%. The petroleum-derived TPAH fraction in mussel tissues has decreased with time, reflecting the decreasing release of EVOS residues in shoreline sediments. These results show that PAH from EVOS residues that remain buried in shoreline sediments after the early 1990s are in a form and at locations that have a low accessibility to mussels living in the intertidal zone. 相似文献
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笔者在研究现代沉积时,在我国舟山群岛的现代海滨沙滩上发现了一种前人未曾报道的新波痕类型,实录了其形态,分析了其成因,取名为涡流波痕。涡流波痕形态奇特,若干列波痕呈放射状排列;单列波痕中段呈弧形前凸。将沉积构造与水动力相联系是国际上尚处于研究早期的沉积动力学的主要内容。流体动力学中有一种水质点绕轴作旋转 相似文献
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波痕是沉积岩最常见的特征之一，在现代和古代沉积物中均常见。水流波痕的形态取决于环境和水动力
因素。艾伦（1968，1969）和赖内克（1971，1973，1980）分别作过研究。笔者于 1987年发现了涡流波痕，①这不仅
增添了新的波痕类型，而且对波痕成因有新的认识。 相似文献
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世界海岸分类自李希霍芬(F．V．Richihofen,1886)的分类问世至今,经历了一个多世纪,出现过许多分类,但因对象的复杂、影响因素繁多、研究程度不够等原因,尚无一公认的海岸分 相似文献
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Melchiorri A Ade PA de Bernardis P Bock JJ Borrill J Boscaleri A Crill BP De Troia G Farese P Ferreira PG Ganga K de Gasperis G Giacometti M Hristov VV Jaffe AH Lange AE Masi S Mauskopf PD Miglio L Netterfield CB Pascale E Piacentini F Romeo G Ruhl JE Vittorio N 《The Astrophysical journal》2000,536(2):L63-L66
We use the angular power spectrum of the cosmic microwave background, measured during the North American test flight of the Boomerang experiment, to constrain the geometry of the universe. Within the class of cold dark matter models, we find that the overall fractional energy density of the universe Omega is constrained to be 0.85相似文献
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