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71.
煤矸石堆放对水环境的影响——以山东省一些煤矸石堆为例   总被引:25,自引:0,他引:25  
采集山东省一些煤矿煤矸石及其堆放区水体的样品进行研究 ,可知煤矸石中硫 (主要赋存在黄铁矿中 )的质量分数为 0 2 8%~ 2 9% ,是重要的水质污染源。大量的Si,Al,Fe ,Ca ,Mg等常量元素及含量较高的As,Pb ,Cr,Mn等微量元素都能对水体产生污染 ;煤矸石堆放区水体的pH值为 4 43~7 93,总硬度高 ,SO2 -4 浓度高 (平均为 12 0 1 0 2mg/L ,最高为 2 6 37 6 9mg/L ,超标 10倍多 ) ,微量有毒、有害组分 (Be ,V ,Mn ,Sr ,Mo ,Ni,F等 )均存在超标或浓度过高现象。对风化的与新鲜的煤矸石分别进行浸泡和淋滤实验发现 :黄铁矿的氧化导致了煤矸石堆放区相邻水体的SO2 -4 ,Fe ,Al的浓度增大 ,黄铁矿氧化生成的酸及其与钙镁盐岩的反应致使pH值变化范围大 ,水体的硬度升高 ;煤矸石风化生成的大量酸使淋滤液pH值降低 ,在酸的作用下水中Ca2 + 和Mg2 + 的浓度增大并维持在一定的水平 ,风化使煤矸石中的黄铁矿发生氧化并以可溶性Fe和硫酸盐形式迁移至淋滤液中 ,煤矸石中赋含的多种多环芳烃能迁移到附近的水体中 ,对环境造成大量的有机物污染 ,这一污染应引起有关方面的高度重视。  相似文献   
72.
The fate of polycyclic aromatic hydrocarbon (PAH) contamination in a mangrove swamp (Yi O) in Hong Kong after an oil spill accident was investigated. The concentrations and profiles of PAHs in surface sediments collected from five quadrats (each of 10 m×10 m) covering different degrees of oil contamination and the most contaminated mangrove leaves were examined in December 2000 (30 days after the accident) and March 2001 (126 days later). The concentrations of total PAHs in surface sediments ranged from 138 to 2135 ng g−1, and PAHs concentrations decreased with time. In the most contaminated sediments, total PAHs dropped from 2135 (30 days) to 1196 ng g−1 (120 days), and the decrease was smaller in less contaminated sediments. The percentage reduction in sediment PAHs over three months (44%) was less significant than that in contaminated leaves (85%), indicating PAH in or on leaves disappeared more rapidly. The PAH profiles were very similar in sediments collected from quadrats Q1 and Q2 with benzo[a]anthracene and pyrene being the most abundant PAH compounds, but were different in the other three quadrats. The proportion of the light molecular weight PAHs to total PAHs increased after three months, especially phenanthrene. Results suggest that physical and photo-chemical weathering (tidal washing and photo-oxidation) of crude oil in surface sediments and on plant leaves were important processes in the first few months after the oil spill. The PAH contamination in Yi O swamp came from both petrogenic and pyrolytic sources. The petrogenic characteristic in the most contaminated sediment was confirmed with high values of phenanthrene to anthracene ratio (>10) and low values of fluoranthene to pyrene ratio (0.3–0.4).  相似文献   
73.
The concentrations of n-alkanes and polycyclic aromatic hydrocarbons (PAHs) are determined in atmospheric aerosol samples collected at a rural sampling site in Hungary. For the n-alkanes the chromatographic profiles are established and the average carbon number and carbon preference index (CPI) are calculated. An attempt is made to obtain the origin of n-alkanes found in atmospheric aerosol samples. Based on the results of the measurements the probable importance of a round-the-year biogenic source for the n-alkanes with CPIs close to unity is emphasized.  相似文献   
74.
Norwegian coastal waters are subject to PAH contamination from electrochemical industries such as aluminium smelters. Evidence of PAH exposure has been established in fish and bivalves. The present study tests the applicability of a novel crustacean PAH exposure biomarker to a PAH contamination gradient in the field (Karmsund Strait, SW Norway). Fluorescence analysis of urine samples collected from crabs at each site revealed 1-OH pyrene "equivalent" levels (indicative of pyrogenic PAH contamination) decreased with increasing distance from a point source of pyrogenic PAH (a large aluminium works). The assay was shown to be suitable for the detection of PAH exposure in wild crustacean populations, for discriminating between contaminated and clean sites and is also sufficiently sensitive to detect gradients of PAH contamination. The method provides a rapid, inexpensive and non-destructive measure of biologically available PAH in crustaceans.  相似文献   
75.
The uptake of polycyclic aromatic hydrocarbons (PAHs) by marine deposit-feeding invertebrates can be determined by screening for PAH-derived metabolites. We identified 1-hydroxypyrene as the only intermediate metabolite in tissue of four species of deposit-feeding polychaetes, Nereis diversicolor, Nereis virens, Arenicola marina, and Capitella sp. I exposed to pyrene spiked sediment. Synchronous fluorescence spectroscopy (SFS) provides a fast and simple method for both qualitative and quantitative analysis of 1-hydroxypyrene in all four species. The SFS assay was validated using HPLC with ultraviolet detection. A good correlation between 1-hydroxypyrene concentrations determined by the two methods was observed. We used HPLC with fluorescence detection combined with enzymatic hydrolysis of conjugated metabolites to investigate species specific metabolite patterns. A tentative aqueous metabolite identification scheme indicates that Nereid polychaetes predominately make use of glucuronide conjugation whereas Capitella sp. I. and Arenicola marina appear to utilize predominantly sulfate and/or glucoside conjugation. The usefulness of 1-hydroxypyrene as a biomarker for PAH exposure in deposit-feeding invertebrates is discussed.  相似文献   
76.
A new scheme of radiation transfer for understanding the infrared spectra of HII regions, has been developed. This scheme considers non-equilibrium processes (e.g. transient heating of the very small grains, VSG; and the polycyclic aromatic hydrocarbon, PAH) also, in addition to the equilibrium thermal emission from normal dust grains (BG). The spherically symmetric interstellar dust cloud is segmented into a large number of “onion skin” shells in order to implement the non-equilibrium processes. The scheme attempts to fit the observed SED originating from the dust component, by exploring the following parameters: (i) geometrical details of the dust cloud, (ii) PAH size and abundance, (iii) composition of normal grains (BG), (iv) radial distribution of all dust (BG, VSG & PAH). The scheme has been applied to a set of five compact H II regions (IRAS 18116 − 1646, 18162 − 2048, 19442 + 2427, 22308 + 5812, and 18434 - 0242) whose spectra are available with adequate spectral resolution. The best fit models and inferences about the parameters for these sources are presented.  相似文献   
77.
Measurements of chemical contaminants in caged (transplanted) and resident mussel populations have become a routine tool for monitoring and assessing the status and trends of coastal water quality. However, few long-term data sets are available to assess the comparability and efficacy of these two monitoring approaches. Three long-term independent data sets exist for Boston Harbor: the National Mussel Watch program has analyzed resident blue mussels (Mytilus edulis) from the Boston Harbor/Massachusetts Bay region for over twenty years, the Massachusetts Water Resources Authority has annually deployed caged (transplanted) mussels (M. edulis) to assess bioaccumulation potential of sewage effluent discharged under its NPDES permit for over fourteen years, and the GulfWatch program has analyzed resident blue mussel populations for over twelve years. Together, these data provide consistent and comparable information on temporal and spatial changes in chemical contamination in Boston Harbor as steps were taken to reduce contaminant loading. The data also demonstrate the complementary nature of resident and caged (transplanted) mussels for assessing contaminant trends even when the basic approaches and sampling frequency differ. These fifteen-year data sets demonstrate contaminant concentrations in mussels from Boston Harbor are similar and with few exceptions have significantly decreased since the early 1990s. The observed trends also demonstrate broad scale improvements to the quality of Boston Harbor and expand understanding of the response of coastal systems to interventions that reduce the load of chemicals to the ocean.  相似文献   
78.
In presence of disinfectants, PAH are remobilized from the coal tar lining of water distribution mains. Reactions of the PAH with chlorine and chlorine dioxide can lead to chlorinated PAH that might show higher mutagenic effects than the parent PAH. The application of the solid-phase microextraction as a sampling preparation method in combination with a gas chromatographic mass spectrometric device is a reliable and useful method to achieve detection limits in the lower nanogramme-per-liter level for PAH and chlorinated PAH. Thus, the reactions of four PAH (anthracene, fluoranthene, fluorene, and phenanthrene) with chlorine and chlorine dioxide under conditions prevalent in drinking water distribution systems could be investigated. In batch experiments with demineralized and drinking water at pH 7, the concentrations of fluoranthene, fluorene, and phenanthrene remained constant, whereas anthracene reacted quantitatively with both disinfectants. In these reactions, no chlorinated products could be detected, only mono-hydroxyanthracene and anthraquinone were formed. A reaction mechanism for both reaction products is proposed. The results suggest that oxidation is the major pathway of the reaction of PAH with disinfectants in the systems under investigation.  相似文献   
79.
Polycyclic aromatic hydrocarbon (PAH) bioaccumulation by the polychaete worm Streblospio benedicti (Webster) was measured under exposure to PAH-contaminated sediments in the field and for 28 d in the laboratory. Streblospio benedicti collected from field sediments contaminated at 2.94, 1.07, and l.52 μg g−1 fluoranthene (FLU), benz[a]anthracene (BAA), and benzo[a]pyrene (BAP), bioaccumulated those PAHs at 1.53, 0.215, and 0.332 μg g−1, while worms isolated from less contaminated field sediments (0.399, 0.228, 0.288 μg g−1 FLU, BAA, and BAP) had FLU, BAA, and BAP body burdens of 0.543, 0.236, and 0.083 μg g−1. Worms incubated for 28 d in PAH-spiked sediments (1.52, 0.991, 0.504 μg g−1 FLU, BAA, and BAP) bioaccumulated those PAHs at 0.382, 0.966, and 0.602 μg g−1, respectively. Data normalization to organism lipid and sediment organic carbon (biota-sediment accumulation factors [BSAFs] strongly suggest that Streblospio PAH bioaccumulation was directly related to percent sediment organic carbon, but BSAFs were substantially lower than predicted by equilibrium partitioning theory. BSAFs decreased with increasing PAH log Kow, in worms collected from field sediments, but in spiked sediments BSAFs increased with increasing PAH hydrophobicity. This disparity may have been caused by insufficient spiked-sediment equilibration time (1.5h) in the case of the laboratory test sediments.  相似文献   
80.
This study compared species identity, microplastics, chemical and microbial contamination between consumption mussels and wild type mussels, collected at Belgian department stores and Belgian groynes and quaysides, respectively. Species identification based on genetic analysis showed a high number of Mytilus (M.) edulis compared to M. galloprovincialis and M. edulis/galloprovincialis hybrid mussels. The number of total microplastics varied from 2.6 to 5.1 fibres/10 g of mussel. A higher prevalence of orange fibres at quaysides is related to fisheries activities. Chemical contamination of polycyclic aromatic hydrocarbons and polychlorobiphenyls could be related to industrial activities and water turbidity, with maximum concentrations at the quayside of port Zeebrugge. The inverse was noted for Escherichia coli contamination, which was relatively low at Zeebrugge quayside with a total count of 3.9 × 102 CFU/100 g tissue, due to limited agricultural effluents. Results of this complementary analysis stress the importance of integrated monitoring and quality assessment.  相似文献   
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