全文获取类型
收费全文 | 193篇 |
免费 | 0篇 |
国内免费 | 1篇 |
专业分类
安全科学 | 7篇 |
废物处理 | 12篇 |
环保管理 | 14篇 |
综合类 | 23篇 |
基础理论 | 39篇 |
环境理论 | 1篇 |
污染及防治 | 59篇 |
评价与监测 | 19篇 |
社会与环境 | 18篇 |
灾害及防治 | 2篇 |
出版年
2023年 | 4篇 |
2022年 | 9篇 |
2021年 | 4篇 |
2020年 | 5篇 |
2019年 | 5篇 |
2018年 | 7篇 |
2017年 | 7篇 |
2016年 | 11篇 |
2015年 | 8篇 |
2014年 | 13篇 |
2013年 | 20篇 |
2012年 | 11篇 |
2011年 | 14篇 |
2010年 | 8篇 |
2009年 | 15篇 |
2008年 | 13篇 |
2007年 | 5篇 |
2006年 | 10篇 |
2005年 | 7篇 |
2004年 | 4篇 |
2003年 | 2篇 |
2002年 | 3篇 |
2001年 | 2篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1992年 | 2篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有194条查询结果,搜索用时 15 毫秒
141.
Hemispheric asymmetries and side biases have been studied in humans mostly in laboratory settings, and evidence obtained in
naturalistic settings is scarce. We here report the results of three studies on human ear preference observed during social
interactions in noisy environments, i.e., discotheques. In the first study, a spontaneous right-ear preference was observed
during linguistic exchange between interacting individuals. This lateral bias was confirmed in a quasi-experimental study
in which a confederate experimenter evoked an ear-orienting response in bystanders, under the pretext of approaching them
with a whispered request. In the last study, subjects showed a greater proneness to meet an experimenter’s request when it
was directly addressed to the right rather than the left ear. Our findings are in agreement both with laboratory studies on
hemispheric lateralization for language and approach/avoidance behavior in humans and with animal research. The present work
is one of the few studies demonstrating the natural expression of hemispheric asymmetries, showing their effect in everyday
human behavior. 相似文献
142.
Introduced Pacific oysters (Crassostrea gigas) have shown rapid expansion in the Oosterschelde estuary, while stocks of native bivalves declined slightly or remained stable.
This indicates that they might have an advantage over native bivalve filter feeders. Hence, at the scale of individual bivalves,
we studied whether this advantage occurs in optimizing food intake over native bivalves. We investigated feeding current characteristics,
in which potential differences may ultimately lead to a differential food intake. We compared feeding currents of the invasive
epibenthic non-siphonate Pacific oyster to those of two native bivalve suspension feeders: the epibenthic siphonate blue mussel
Mytilus edulis and the endobenthic siphonate common cockle Cerastoderma edule. Inhalant flow fields were studied empirically using digital particle image velocimetry and particle tracking velocimetry.
Exhalant jet speeds were modelled for a range of exhalant-aperture cross-sectional areas as determined in the laboratory and
a range of filtration rates derived from literature. Significant differences were found in inhalant and exhalant current velocities
and properties of the inhalant flow field (acceleration and distance of influence). At comparable body weight, inhalant current
velocities were lower in C. gigas than in the other species. Modelled exhalant jets were higher in C. gigas, but oriented horizontally instead of vertically as in the other species. Despite these significant differences and apparent
morphological differences between the three species, absolute differences in feeding current characteristics were small and
are not expected to lead to significant differences in feeding efficiency. 相似文献
143.
The structure of male mating signals is often influenced by age. The causes and consequences of age-based signal variation
have been much studied in visual, acoustic, and chemical signaling modalities, but are less explored in species that use vibrational
signals for mate attraction. However, the complex structure of many vibrational signals makes them ideal for investigating
the relationships between age, signal variation, and patterns of female choice. In the thornbug treehopper, Umbonia crassicornis, females mate more often with older males, but the mechanism underlying older male mating success is unknown. Our goals in
this study were to determine whether male vibrational mate advertisement signals vary with age, and, if so, whether females
prefer the signals of older males. We recorded male signals over four consecutive weeks beginning at the onset of signaling
(a period spanning most of the male reproductive lifespan), and measured ten temporal, spectral, and energy-related parameters
from each signal. Several features of male signals changed markedly with age. However, females responded similarly to signals
representing males of different ages, indicating that they do not favor older males on the basis of long distance mate advertisement
signals. Nonetheless, the results reveal that even in short-lived, determinate growth species age can have surprisingly large
effects on mating signals, and we discuss some factors that may contribute to age-related signal variability in U. crassicornis. 相似文献
144.
The carbonate radical (CO 3 ?· ) is a photoinduced transient species occurring in surface waters. The carbonate radical can transform both natural compounds and xenobiotics. For instance, it can react with electron-rich substrates such as anilines, phenols and organic sulfur compounds. Here we used the APEX software to assess photochemical reactions, including the formation rates of transient species, based on water chemistry and depth, under summertime irradiation conditions. We found that the reaction between peroxynitrite and carbon dioxide is a potentially significant source of CO 3 ?· in sunlit surface waters, and could account for up to 10–15 % of the total CO 3 ?· formation. The peroxynitrite pathway to CO 3 ?· would be most significant at pH 7–8 and would be enhanced in waters with elevated nitrate and low alkalinity. Therefore, the proposed process could add to the known photochemical sources of CO 3 ?· in surface-water environments. 相似文献
145.
146.
147.
Nutrient stoichiometry in Sphagnum along a nitrogen deposition gradient in highly polluted region of Central-East Europe 总被引:1,自引:0,他引:1
We investigated the variation of N:P and N:K ratio in ombrotrophic Sphagnum plants along a gradient of atmospheric N deposition from 1 to 2.5 g m−2 year−1 in Central-East Europe. The N:P and N:K ratio in Sphagnum capitula increased significantly along the N deposition gradient. Sphagnum species from the Cuspidata section were characterised by significantly lower ratios at low N deposition. When we compared the observed N:P ratios in Sphagnum plants with the values reported in a previous European-wide study, we found a correspondence in nutrient stoichiometry only for a few bogs: higher P concentration in Sphagnum capitula caused a lower N:P ratio in most of the study bogs so that Sphagnum plants still seem N-limited despite their N saturation. Interaction between summer water table decrease and aerial liming of surrounding forests is proposed as an explanation for this discrepancy. Local forestry practice interacting with climate thus alter N:P stoichiometry of Sphagnum along the N deposition gradient. 相似文献
148.
Villarini M Moretti M Dominici L Fatigoni C Dörr AJ Elia AC Monarca S 《Chemosphere》2011,84(10):1521-1526
A sensitive and rapid method to evaluate toxic and genotoxic properties of drinking water supplied from Lake Trasimeno (Umbria, Central Italy) was worked out analysing bile in Cyprinus carpio exposed for 20 d to lake water treated with 3 different disinfectants, sodium hypochlorite (NaClO), chlorine dioxide (ClO2) and peracetic acid (PAA). Fish were sacrificed at 0, 10 and 20 d in order to investigate the time course of these endpoints. An aliquot of bile samples was fractionated by adsorption on C18 silica cartridges and the genotoxic potential of whole bile and of bile fractions was evaluated by the single-cell microgel-electrophoresis (comet) assay on human colonic adenocarcinoma cells (Caco-2). Bile (both whole and fractionated) from specimens exposed to the three disinfectants always showed a genotoxic activity as compared to the control group. The results of this study provide evidence that all three disinfectants cause an increase in bile genotoxicity of chronically exposed fish. 相似文献
149.
Waste combustion processes are responsible of particles and gaseous emissions. Referring to the particle emission, in the last years specific attention was paid to ultrafine particles (UFPs, diameter less than 0.1 μm), mainly emitted by combustion processes. In fact, recent findings of toxicological and epidemiological studies indicate that fine and ultrafine particles could represent a risk for health and environment. Therefore, it is necessary to quantify particle emissions from incinerators also to perform an exposure assessment for the human populations living in their surrounding areas.To these purposes, in the present work an experimental campaign aimed to monitor UFPs was carried out at the incineration plant in San Vittore del Lazio (Italy). Particle size distributions and total concentrations were measured both at the stack and before the fabric filter inlet in order to evaluate the removal efficiency of the filter in terms of UFPs. A chemical characterization of UFPs in terms of heavy metal concentration was performed through a nuclear method, i.e. Instrumental Neutron Activation Analysis (INAA), as well as a mineralogical investigation was carried out through a Transmission Electron Microscope (TEM) equipped with an Energy Dispersive Spectrometer (EDS) in order to evaluate shape, crystalline state and mineral compound of sampled particles.Maximum values of 2.7 × 107 part. cm−3 and 2.0 × 103 part. cm−3 were found, respectively, for number concentration before and after the fabric filter showing a very high efficiency in particle removing by the fabric filter. With regard to heavy metal concentrations, the elements with higher boiling temperature present higher concentrations at lower diameters showing a not complete evaporation in the combustion section and the consequent condensation of semi-volatile compounds on solid nuclei. In terms of mineralogical and morphological analysis, the most abundant compounds found in samples collected before the fabric filter are Na–K–Pb oxides followed by phyllosilicates, otherwise, different oxides of comparable abundance were detected in the samples collected at the stack. 相似文献
150.
Focardi S Loiselle SA Mazzuoli S Bracchini L Dattilo AM Rossi C 《Journal of environmental management》2008,86(2):383-389
Territorial indicators based on the satellite measured reflected or emitted energy can provide valuable information on the spatial evolution of a territory. Information regarding land use, biomass coverage and radiant temperature were obtained from remotely obtained measurements for each municipality in the Province of Siena. Remotely sensed data were combined into different indices to compare characteristics of land cover between territories and create an information base for continued study. A classification was performed on a municipal level and land use classes were grouped together and a general index of use pressure was created. A vegetation index was used to compare biomass densities. A radiant temperature index was calculated using measure thermal infrared emissions. The results of these analyses allowed researchers to examine the intra and inter-municipal spatial heterogeneity within the Province. A comparison between the results of each index was made and the problems related to the use of such indices were examined. 相似文献