1999年海城-岫岩地震序列的精准定位   总被引：1，自引：0，他引：1       下载免费PDF全文

杨智娴  Brian W Stump  陈运泰  Rongmao Zhou  Chris T Hayward 《地震学报》2011,33(3):271-278

1999年11月29日,北京时间12点10分39秒(04:10:39 UTC)在我国辽宁海城-岫岩地区发生了一次Ms5.4地震.这次地震是继1975年2月4日海城Ms7.3地震之后该地区发生的震级最大的一次地震.区域性的辽宁数字地震台网记录了这一序列的前震、主震与 余震.本文运用该台网的记录资料,用双差法对海城-岫岩地...  相似文献   

Surflan and oryzalin impair reproduction in the teleost medaka (Oryzias latipes)     

Hall LC  Okihiro M  Johnson ML  Teh SJ 《Marine environmental research》2007,63(2):115-131

We conducted studies to determine if the xenoestrogens Surflan and its active ingredient oryzalin, affect indices of reproductive fitness in medaka (Oryzias latipes). Oryzalin (0.5, 0.25mg/l) or Surflan (2.0 microl/l) and oryzalin (0.5mg/l) significantly increased the mean number of non-fertilized eggs produced by treated females paired with untreated males, or by untreated females paired with treated males. Oryzalin (1.0, 0.5, 0.25mg/l) and Surflan (3.8, 2.0, 1.0 microl/l) significantly affected the time to hatch of eggs from treated females paired with untreated males, and from untreated females paired with treated males. Surflan (3.8, 2.0, 1.0 microl/l) induced intersex lesions in 80-100% of males. Oryzalin-exposed males exhibited a significant increase in the incidence of necrotic spermatids and necrotic spermatogonia, while oryzalin-exposed females had significantly fewer immature oocytes and an increase in the occurrence of hyperplastic ovaries. Our results indicate that Surflan and oryzalin affect both reproduction and gonadal histology in male and female medaka.  相似文献   

岩石压入硬度与声发射参数关系的研究     

吴光琳 Jung  SJ 《成都地质学院学报》1993,20(1):81-86

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Whaling: will the Phoenix rise again?     

Holt SJ 《Marine pollution bulletin》2007,54(8):1081-1086

It is argued that Japan’s authorities and entrepreneurs involved in whaling and the whale-meat trade have a long-term goal of rebuilding a large and profitable industry of pelagic whaling, particularly in the Southern Hemisphere, in the next 20 years or so. They have made large investments in this enterprise since the so-called moratorium on commercial whaling was adopted by the International Whaling Commission in 1982. These include, but are not confined to, state subsidizing of an expanding and diversifying 20-year programme of commercial whaling under provisions in all relevant international agreements since 1937 that permit unlimited and unilaterally decreed whaling, supposedly for scientific purposes, provided that the commodities from the whales killed are fully utilized. The context of this is the monopoly of technical knowledge, special skills and the market for valuable whale-meat that Japanese enterprises acquired in the post-world war II period, having broken - in 1937 - the strongly defended de facto Anglo-Norwegian monopoly of technology, skills, access to Antarctic whaling grounds and the market for whale-oil that had existed until then. The attraction of ‘scientific whaling’ is not only that it by-passes any internationally agreed catch-limits but that it also circumvents all other rules - many dating fr/om the League of Nations whaling convention of 1931 - regarding protected species, closed areas, killing of juveniles, less inhumane killing methods, etc. The groundwork is being laid to justify that resumed whaling on partially recovered whale stocks will be at the unsustainable levels that will be profitable again. This justification is based on spurious assertions that numerous and hungry whales threaten the world’s fisheries, and that the abundance and possible increase in some whale species is impeding the recovery of other, severely depleted, and potentially more valuable species such as the blue whale. If the scenario presented here is correct it has important implications for attempts by the international community either to bring a negotiated end to commercial whaling or to bring all whaling back under international control, as the international law of the sea requires, and to ensure that any permitted exploitation of recovered whale populations will be sustainable, under a precautionary regime.  相似文献   

Contemporary 14C radiocarbon levels of oxygenated polybrominated diphenyl ethers (O-PBDEs) isolated in sponge-cyanobacteria associations     

Guitart C  Slattery M  Ankisetty S  Radwan M  Ross SJ  Letcher RJ  Reddy CM 《Marine pollution bulletin》2011,62(3):631-636

Considerable debate surrounds the sources of oxygenated polybrominated diphenyl ethers (O-PBDEs) in wildlife as to whether they are naturally produced or result from anthropogenic industrial activities. Natural radiocarbon (¹⁴C) abundance has proven to be a powerful tool to address this problem as recently biosynthesized compounds contain contemporary (i.e. modern) amounts of atmospheric radiocarbon; whereas industrial chemicals, mostly produced from fossil fuels, contain no detectable ¹⁴C. However, few compounds isolated from organisms have been analyzed for their radiocarbon content. To provide a baseline, we analyzed the ¹⁴C content of four O-PBDEs. These compounds, 6-OH-BDE47, 2′-OH-BDE68, 2′,6-diOH-BDE159, and a recently identified compound, 2′-MeO-6-OH-BDE120, were isolated from the tropical marine sponges Dysidea granulosa and Lendenfeldia dendyi. The modern radiocarbon content of their chemical structures (i.e. diphenyl ethers, C₁₂H₂₂O) indicates that they are naturally produced. This adds to a growing baseline on, at least, the sources of these unusual compounds.  相似文献   

Cetaceans and military sonar: a need for better management     

Dolman SJ  Parsons EC  Wright AJ 《Marine pollution bulletin》2011,63(1-4):1-4

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Ecological significance of alkaline phosphatase activity and phosphatase-hydrolyzed phosphorus in the northern part of Gamak Bay, Korea   总被引：1，自引：0，他引：1  

Kwon HK  Oh SJ  Yang HS 《Marine pollution bulletin》2011,62(11):2476-2482

We investigated the ecological significance of alkaline phsophatase (APase) and alkaline phosphatase-hydrolyzable phosphorus (APHP) in the northern part of Gamak Bay, Korea. APase activity was detectable throughout the year, and dissolved inorganic phosphorus (DIP) concentration and APase activity are highly correlated and can be regarded as an indicator of DIP-limiting conditions. Also, a strong linear positive correlation between APase activity and Chl a concentration indicated that the major part of APase activity may have been induced by phytoplanktons. The APHP proportion in dissolved organic phosphorus (DOP) was above ca. 30% from winter to spring and below ca. 15% from summer to autumn due to freshwater discharge and uptake by phytoplankton. APHP may play an important role in species competition in coastal area such as northern part of Gamak Bay where DIP is limiting. Thus, APase induction by phytoplanktons may be ecologically significant, allowing dominance by these organisms under DIP-limiting conditions.  相似文献   

Tracing sewage pollution in the Pearl River Delta and its adjacent coastal area of South China Sea using linear alkylbenzenes (LABs)   总被引：4，自引：1，他引：3  

Luo XJ  Chen SJ  Ni HG  Yu M  Mai BX 《Marine pollution bulletin》2008,56(1):158-162

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Biomarker responses in caged rockfish (Sebastes schlegeli) from Masan Bay and Haegeumgang, South Korea     

Jung JH  Kim SJ  Lee TK  Shim WJ  Woo S  Kim DJ  Han CH 《Marine pollution bulletin》2008,57(6-12):599-606

The purpose of this study was to compare enzymatic biomarker activities in fish caged at two sites, Masan Bay (contaminated) and Haeguemgang (reference). In the present study, ethoxyresorufin O-deethylase (EROD), brain acetyl cholinesterase (bAChE), muscle acetyl cholinesterase (mAChE) and butyryl cholinesterase (mBChE) in caged rockfish (Sebastes schlegeli) were measured 0, 1, 3, 7, 14, 21 and 30 days after caging. The level of CYP1A mRNA and Protein expression was induced higher in Masan Bay at 1, 3, 7, 14 and 30 days after caging. EROD activity in the caged fish was significantly higher in Masan Bay than in Haeguemgang 3 and 7 days after caging, but not at 14 and 30 days after caging. bAChE activity was significantly inhibited at 7 and 14 days after caging in Masan Bay. However, mBChE activity was not significantly inhibited during the experiment. Taken together, the data suggest that the caged fish were exposed, at least transiently, to CYP1A inducers and ChE inhibitors, which is consistent with our previous observations.  相似文献   

"A stream depletion field experiment," by Bruce Hunt,Julian Weir,and Bente Clausen,March-April 2001 issue,v. 39, no.2: 283-289     

Kollet SJ  Zlotnik VA 《Ground water》2002,40(4):448-449

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