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11.
Differential developmental toxicity of naphthoic acid isomers in medaka (Oryzias latipes) embryos 总被引:1,自引:0,他引:1
Michael W. Carney Kyle Erwin Ron Hardman Bonny Yuen David C. Volz David E. Hinton Seth W. Kullman 《Marine pollution bulletin》2008,57(6-12):255
Polycyclic aromatic hydrocarbons (PAHs) are widespread persistent pollutants that readily undergo biotic and abiotic conversion to numerous transformation products in rivers, lakes and estuarine sediments. Here we characterize the developmental toxicity of four PAH transformation products each structural isomers of hydroxynaphthoic acid: 1H2NA, 2H1NA, 2H3NA, and 6H2NA. Medaka fish (Oryzias latipes) embryos and eleutheroembryos were used to determine toxicity. A 96-well micro-plate format was used to establish a robust, statistically significant platform for assessment of early life stages. Individual naphthoic acid isomers demonstrated a rank order of toxicity with 1H2NA > 2H1NA > 2H3NA > 6H2NA being more toxic. Abnormalities of circulatory system were most pronounced including pericardial edema and tube heart. To determine if HNA isomers were AhR ligands, spatial-temporal expression and activity of CYP1A was measured via in vivo EROD assessments. qPCR measurement of CYP1A induction proved different between isomers dosed at respective concentrations affecting 50% of exposed individuals (EC50s). In vitro, all ANH isomers transactivated mouse AhR using a medaka CYP1A promoter specific reporter assay. Circulatory abnormalities followed P450 induction and response was consistent with PAH toxicity. A 96-well micro-plates proved suitable as exposure chambers and provided statistically sound evaluations as well as efficient toxicity screens. Our results demonstrate the use of medaka embryos for toxicity analysis thereby achieving REACH objectives for the reduction of adult animal testing in toxicity evaluations. 相似文献
12.
N. Aarab D.M. Pampanin A. Nvdal K.B.
ysd L. Gastaldi R.K. Bechmann 《Marine pollution bulletin》2008,57(6-12):569
Histopathological characteristics of specific organs express condition, and represent time-integrated impacts on the organism stemming from alterations at lower levels of biological organisation. As integrative parameters, histochemical investigations have proved to be sensitive tools to detect effects of chemical compounds.The objective of this study was to determine changes in the tissues of mussels collected at a PAH contaminated site compared to a reference site using histopathological and histochemical parameters: lipofuscin (LF) accumulation in mussel digestive gland, and lysosomal membrane stability (LMS), and using additional information provided by body burden analysis to compare the sensitivity of these parameters.The histochemical measurements for both LF and LMS gave a clear indication of a high level of stress in animals from the PAH contaminated site. This LF accumulation in lysosomes is the result of peroxidation of autophagocytosed proteins associated with protein aggregates and oxidatively damaged organelles. These measurements were able to detect the effects of PAHs, and showed a strong relationship with the body burden results. 相似文献
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Rosario Iturbe Alejandrina Castro Guillermina Perez Carlos Flores Luis G. Torres 《Environmental Geology》2008,55(8):1785-1795
For the year 1996, 366 incidents related with clandestine poaching of oil-products were reported in Mexico, 159 in 1997, and
240 in 1998. For the year 2003 (the most recently reported figure), there were 136 events. Petroleos Mexicanos (PEMEX), very
concerned with the environmental agenda, has developed programs oriented to diminish contamination levels in all of its oil
facilities. This work was aimed at characterizing zones around polyduct segments, pipelines, pumping stations, and right-of-way
pipelines located in the center of Mexico. The TPH contaminated sites were, in decreasing order, polyduct km 39 + 150 > polyduct
km 25 + 020 > Zoquital > Tepetitlan > Catalina > Venta Prieta > Ceiba. Most of the sampled points showed the presence of more than one of the 16 PAHs considered by USEPA as priority pollutants.
Except point TEPE 2A, where no PAHs were detected, all the sampled points showed values from low to medium concentrations;
however, values found at the sites did not exceed the limits according to the Mexican or the American legislation. The place
with the largest contaminated area corresponded to the polyduct km 39 + 150, with 130 m2 and 260 m3 to be treated. The least contaminated area was that around the JUAN 4 point at Juandho station, with 20 m2 and 22 m3 of contaminated soil. The total area to be treated is about 230 m2 and 497 m3. 相似文献
16.
The degree and the contribution of each point source to the pollution were determined in the Izmit Bay during the period 1999–2000.
During 8 campaigns, samples from 11 points in the channels and water samples from 5 points in the coastal sea were collected
for chemical analysis. The important pollutant parameters taken into account are inflow of total organic carbon (TOC), total
suspended solids (TSS), total phosphorus (TP), total nitrogen (TN), nitrate, ortho-phosphate, ammonia and total polycyclic aromatic hydrocarbons (t-PAHs) in the discharge channels, and TOC, TSS, nitrate,
ortho-phosphate, chlorophyll-a, temperature, dissolved oxygen (DO), and salinity in the coastal stations of the Bay. It should
be pointed out that the industrial wastewaters entering the bay are partially treated but domestic wastes are discharged directly
into the surface waters without any treatment. Of the pollution parameters measured in the channels, the highest concentrations,
except TP, were observed in the Dil River and in the Eastern Channel. Concentrations of TOC, TSS, TN, TP, ammonia, nitrate
and o-phosphate were found at concentrations of 231, 290, 152, 3.8, 16, 79, and 3.07 mg/L, respectively. Annual inflows of TOC
were 21,301, 580, and 775 t/year and for TSS were 26,742, 585, and 1505 t/year in the western, central and eastern parts,
respectively. The results show that the water quality of the bay has been deteriorated and 80% of the pollution was caused
by Dil River for all parameters measured. 相似文献
17.
Offset of prograde hydrothermal alterations by retrograde reactions is evident in sediments from a piston core (PC6, 8 m long) from the Guaymas Basin, Gulf of California. Geochemical and mineralogical analyses of sediments and pore fluids show superimposed geochemical signals that indicate currently active reactions are modifying previously formed secondary solids. Hydrothermal barite was formed in a previously active flow channel between 150 and 250 cm depth. Hydrothermal gypsum is presently dissolving at depths > 780 cm, below which hydrothermal fluid flow is channeled by a secondary dolomite layer. Thermal stress of organic matter generates hydrothermal gas and petroleum having wide ranges of compositions and maturities. A significant amount of hydrothermally generated oil has been transported laterally through a porous debris flow (approx. 240 cm subbottom), overwhelming the indigenous bituminous matter. Water soluble petroleum constituents have disseminated throughout the cored sediments. From 400 to 700 cm depth the immature organic matter continues to experience thermally-enhanced diagenesis, and an even higher thermal stress has occurred at the bottom of the core. Enhanced bacterial degradation of organic matter has led to depletion of pore water sulfate and enrichment of ammonium (NH4+) in both pore fluid and sediment, resulting in formation of NH4+ bearing secondary clay minerals at depths below 780 cm. 相似文献
18.
Bioavailable contaminant concentrations are an important component in assessing environmental effects as they directly affect ecosystem health. Shellfish contaminant monitoring programmes have traditionally filled this requirement but are being phased out in some jurisdictions. Passive sampling devices (PSDs) have the potential to replace shellfish monitoring; however, there are still knowledge gaps to address before this can occur. This study assessed the suitability of three different PSDs in providing the required information to replace shellfish monitoring. PSDs were deployed at three historic mussel monitoring sites with different levels of urban influence in the Waitemata Harbour, Auckland, New Zealand. Contaminants of interest were urban heavy metals, plus current and emerging organic contaminants. PSDs provided extremely low detection limits and, for some contaminants, very strong correlations to shellfish. PSDs can currently complement shellfish in monitoring, but it is premature to make conclusions as to the suitability of PSDs in replacing shellfish monitoring until more information is available. 相似文献
19.
A simple sequential extraction technique is presented for the examination of PAH speciation in aquatic sediments. This method is discussed with special emphasis on the sorption of PAH to humic substances and coal-like particles. Sorption experiments were carried out with sediments after treatment with H2O2 or after lipid removal by organic solvent extraction. The results show that lipids exert only a minor influence on PAH sorption. Furthermore, deviations from simple partition behaviour are discussed. 相似文献
20.
Lake-Sediment Evidence for Local and Remote Sources of Atmospherically Deposited Pollutants on Svalbard 总被引:4,自引:4,他引:4
Twenty-one lakes along the west coast of Svalbard were cored between 28 July and 14 August 1995. Five cores were 210Pb dated and analysed for spheroidal carbonaceous particles (SCPs), indicators of deposition from fossil-fuel combustion sources, and trace metals. Surface and pre-industrial levels of five cores were analysed for 10 polychlorinated biphenyl (PCB) isomers and 16 polycyclic aromatic hydrocarbon (PAH) compounds, whilst all 21 surface sediments were analysed for SCPs. Temporal and spatial trends in the atmospheric deposition of pollutants were identified. Whilst temporal patterns of deposited pollutants may have been truncated due to concentrations falling below the limits of detection, spatial patterns showed elevated levels of SCP, PAH, PCB, and possibly Pb within 60–70 km of Isfjord. Tenndammen (U), the closest site to Longyearbyen, showed the highest levels of contamination for all pollutants. Differences in the deposition patterns of PAH and PCB are thought to be due to local sources of PAH from coal combustion whilst PCB sources are remote. It is concluded that the impact from atmospheric deposition on Svalbard is due to a combination of spatially limited local sources superimposed on a broad-scale, long-range pattern. 相似文献