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In 137 females (F) and 94 males (M) aged 21-35 years from organochlorines (OCs) polluted area (POLL) increased thyroid volume (ThV), prevalence of antibodies to thyroperoxidase (TPOab), thyrotropin receptor (TRab) and of impaired fasting glucose (IFG) was found compared to 116 F and 107 M from background pollution area (BCGR). In F and M from POLL also strikingly increased level of PCBs, DDE and HCB was found. Such findings were compared to the generation of their parents aged 41-55 years consisting of 320F/213M from POLL and 406F/231M from BCGR. However, in spite of strikingly lower level of those OCs in young adults from POLL, they showed about the same prevalence of adverse health signs as the old generation. From such reason 44 young F and 40 young M with lowest PCBs level from POLL were selected to obtain nearly the same PCB level as found in all young F and M from BCGR. In such PCB adjusted groups the prevalence of TPOab, TRab, IFG and increased ThV was still significantly higher than that in all young subjects from BCGR. At the same time, also the level of DDE and HCB in such PCBs adjusted groups was considerably lower. It was concluded that such adverse effects in young adults from POLL possibly did not result from their actual OCs levels, but very likely from their exposure to high OCs levels of their mothers during their prenatal and perinatal life. Thus, the data may be compatible with present views on transgenerational transmission of endocrine disruptors action.  相似文献   
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The decline in the supply of natural resources is a cause for concern, especially given continued worldwide population growth. New habits and attitudes toward resource use are slowly being introduced into the everyday lives of persons residing in a number of countries. The term “ecological behavior” refers to acting in favor of the environment, whether these actions are voluntarily or not, or learned or not (Pato & Tamayo, 2006 ). The general objective of this study is to identify the environmental behavior—one of several terms used interchangeably with ecological behavior—of graduate students from a Brazilian federal institution of higher education. We chose this particular group because many of them already act, or will act, as professors. Thus, by virtue of their positions, they will function as opinion leaders who will influence the education of future professionals, establishing a chain through which shared values can gradually change the environmental behavior of society.  相似文献   
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In this work the variation in the elimination capacity of a biofilter as a function of the gas flow and toluene concentration was studied. A bioreactor 0.75 m high x 14.5 cm diameter was used, divided into three equal stages, using compost to support the microorganisms, and sea shells to control the pH. The biofiltration of toluene was evaluated for flows between 0.12 and 0.73 m(3)h(-1) in a concentration range of 1-3.2 gm(-3). It was observed that on increasing the toluene inlet load by 90% (from 37 to 70 gm(3)h(-1)), the conversion by the biofilter varied by only 5% (from 98% to 93%). The biofiltration system used achieved elimination capacities of up to 82 gm(-3)h(-1) for a toluene load of 100 gm(-3)h(-1).  相似文献   
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The aim of this study was to evaluate the DDT, DDE, and 1-hydroxypyrene exposure levels of children living in communities located in southeastern Mexico. The study communities were Lacanja and Victoria in Chiapas state and Ventanilla in Oaxaca state. Children living in Lacanja had total blood DDT levels (mean?±?SD, 29,039.6?±?11,261.4 ng/g lipid) that were significantly higher than those of children in Victoria (10,220.5?±?7,893.1 ng/g lipid) and Ventanilla (11,659.7?±?6,683.7 ng/g lipid). With respect to the 1-hydroxypyrene levels in urine samples, the levels in Lacanja (4.8?±?4.1 μg/L or 4.5?±?3.9 μmol/mol creatinine) and Victoria (4.6?±?3.8 μg/L or 3.9?±?3.0 μmol/mol Cr) were significantly higher than levels found in Ventanilla (3.6?±?1.4 μg/L or 2.5?±?0.5 μmol/mol Cr). In conclusion, our data indicate high levels of exposure in children living in the communities studied in this work. The evidence found in this study could be further used as a trigger to revisit local policies on environmental exposures.  相似文献   
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The aim of these trials was to study the distribution of dieldrin in soil and its translocation to roots and the aerial parts of vegetable crops grown in greenhouses and fields. The main objectives were to characterize dieldrin accumulation in plant tissues in relation to the levels of soil contamination; uptake capability among plants belonging to different species, varieties and cultivars. The presence of the contaminant was quantified by gas chromatography-electron capture detector (GC-ECD) and confirmed by gas chromatography-mass spectrometer (GC-MS). The results showed a translocation of residues in cucurbitaceous fruits and flowers confirming that zucchini, cucumber and melon are crops with high uptake capability. The maximum level of dieldrin residue at 0.01 mg/kg was found to be a threshold value to safeguard the quality production of cucurbits. Tomato, lettuce and celery were identified as substitute crops to grow in contaminated fields.  相似文献   
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Randomly amplified polymorphic DNA (RAPD) banding patterns were compared between samples of the netted dogwhelk Nassarius reticulatus from 11 locations along the NW Iberian Peninsula coast. To detect if rias (estuaries formed by drowned river valleys) might promote genetic differentiation, five sampling sites were located within a ria (ria of Muros) and the remaining six were scattered along open-coast areas at increasing distances from the ria mouth. Population differentiation statistics (Φ-values) were estimated using a hierarchical analysis of molecular variance (AMOVA) with samples sorted into two groups: open-coast and ria populations. Despite a high potential to disperse, AMOVA demonstrated a modest, statistically significant genetic heterogeneity among N. reticulatus populations. Most of the genetic structure resided in differences among open-coast populations; ria populations were genetically homogeneous. No obvious geographical pattern was detected for the pairwise genetic distances (non-metric multidimensional scaling; UPGMA tree; Mantel test). Unlike previous studies with other species at a variety of estuarine systems other than rias, there was no evidence that the ria of Muros may enhance the genetic divergence of N. reticulatus populations. This discrepancy is discussed in relation to the biological features of the species (high dispersal potential and a preference for mid-low estuarine habitat) and the strong hydrographic connectivity between ria and neighbouring off-shore waters.  相似文献   
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Orientation experiments were carried out on Talitrus saltator (Crustacea Amphipoda) at four points along 3 km on a dynamic sandy beach inside the Maremma Regional Park (Grosseto, Italy) to highlight behavioural variation related to distance from a river mouth, to erosion or accretion of shoreline, and to human trampling on the beach. Tests were performed using circular transparent Plexiglas arenas, contemporaneously at the four points. Replicates were made in 2 different months (September 2002 and May 2003), on 2–3 successive days, in the morning and afternoon. The distributions of the angles of orientation were compared for the different points and seasons, and multiple regression analysis was performed to test the effects of environmental and intrinsic variables on orientation. Sandhoppers showed the highest scatter at the eroded shoreline, intermediate scatter at the accreting beach most distant from the river mouth, and consistent orientation seaward at the least disturbed point. Orientation of sandhoppers was significantly affected by season, global radiation, time of day, distance from the river mouth, and human trampling. Sex and air humidity were of minor significance in the multiple regression model. The results, on the one hand, confirm plasticity in orientation of sandhoppers living on a dynamic shoreline, and on the other hand, show that variation in orientation could potentially be used as a bioindicator of shoreline changes.Communicated by R. Cattanevo-Vietti, Genova  相似文献   
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