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231.
Robyn E. Shaw Peter B. Spencer Lesley A. Gibson Judy A. Dunlop Janine E. Kinloch Karel Mokany Margaret Byrne Craig Moritz Harriet Davie Kenny J. Travouillon Kym M. Ottewell 《Conservation biology》2023,37(1):e13989
Landscape-scale conservation that considers metapopulation dynamics will be essential for preventing declines of species facing multiple threats to their survival. Toward this end, we developed a novel approach that combines occurrence records, spatial–environmental data, and genetic information to model habitat, connectivity, and patterns of genetic structure and link spatial attributes to underlying ecological mechanisms. Using the threatened northern quoll (Dasyurus hallucatus) as a case study, we applied this approach to address the need for conservation decision-making tools that promote resilient metapopulations of this threatened species in the Pilbara, Western Australia, a multiuse landscape that is a hotspot for biodiversity and mining. Habitat and connectivity were predicted by different landscape characteristics. Whereas habitat suitability was overwhelmingly driven by terrain ruggedness, dispersal was facilitated by proximity to watercourses. Although there is limited evidence for major physical barriers in the Pilbara, areas with high silt and clay content (i.e., alluvial and hardpan plains) showed high resistance to dispersal. Climate subtlety shaped distributions and patterns of genetic turnover, suggesting the potential for local adaptation. By understanding these spatial–environmental associations and linking them to life-history and metapopulation dynamics, we highlight opportunities to provide targeted species management. To support this, we have created habitat, connectivity, and genetic uniqueness maps for conservation decision-making in the region. These tools have the potential to provide a more holistic approach to conservation in multiuse landscapes globally. 相似文献
232.
Chloé Schmidt Sean Hoban Margaret Hunter Ivan Paz-Vinas Colin J. Garroway 《Conservation biology》2023,37(4):e14064
The International Union for Conservation of Nature (IUCN) Red List is an important and widely used tool for conservation assessment. The IUCN uses information about a species’ range, population size, habitat quality and fragmentation levels, and trends in abundance to assess extinction risk. Genetic diversity is not considered, although it affects extinction risk. Declining populations are more strongly affected by genetic drift and higher rates of inbreeding, which can reduce the efficiency of selection, lead to fitness declines, and hinder species’ capacities to adapt to environmental change. Given the importance of conserving genetic diversity, attempts have been made to find relationships between red-list status and genetic diversity. Yet, there is still no consensus on whether genetic diversity is captured by the current IUCN Red List categories in a way that is informative for conservation. To assess the predictive power of correlations between genetic diversity and IUCN Red List status in vertebrates, we synthesized previous work and reanalyzed data sets based on 3 types of genetic data: mitochondrial DNA, microsatellites, and whole genomes. Consistent with previous work, species with higher extinction risk status tended to have lower genetic diversity for all marker types, but these relationships were weak and varied across taxa. Regardless of marker type, genetic diversity did not accurately identify threatened species for any taxonomic group. Our results indicate that red-list status is not a useful metric for informing species-specific decisions about the protection of genetic diversity and that genetic data cannot be used to identify threat status in the absence of demographic data. Thus, there is a need to develop and assess metrics specifically designed to assess genetic diversity and inform conservation policy, including policies recently adopted by the UN's Convention on Biological Diversity Kunming-Montreal Global Biodiversity Framework. 相似文献
233.
Antecedents of organizational and community embeddedness: The roles of support,psychological safety,and need to belong 下载免费PDF全文
Defining embeddedness as a psychological construct that influences individuals to stay, we draw on conservation of resources theory to develop and test a model of the influence of contextual social support resources on both organizational and community forms of embeddedness. In addition to the direct relationship between support and embeddedness, we also assess the mediating influence of organizational and community psychological safety and the moderating impact of need to belong. Using a multisource sample of employees and coworkers (N = 165), we found support for most of the hypotheses. Social support resources emanating from the organization and the community were positively associated with embeddedness in each domain, and psychological safety mediated these relationships. We also found that need to belong was an important boundary condition in the determination of organizational embeddedness. We discuss the theoretical contributions and practical implications of our findings. 相似文献
234.
Nitrates in concentrated brines can be electrochemically reduced in the cathodic chamber of a split-cell electrochemical reactor
with formation of ammonium (and small amounts of nitrite). Fortunately, ammonium may be electrochemically oxidized to nitrogen
gas in the anodic reaction chamber if a coupled sequential process is used. The presence of chloride in the brine waste is
an important consideration in oxidative electrochemical processes, however, because it cycles through oxidized and reduced
states at the electrode surfaces and in the bulk solution. Electrochemical oxidation converts chloride ions to “active chlorine”
species with additional oxidizing capability (chlorine, hypochlorous acid and hypochlorite – essentially bleach), as well
as to chlorates, depending on the reaction conditions. The production of these active species improves treatment performance
in the ammonium oxidation phase since oxidation is no longer limited to the electrode surface. However, the process must be
engineered to minimize loss of process efficiency due to parasitic side reactions (chloramines and chlorate). In this study,
two-stage batch electrolysis was conducted using a three-electrode (copper anode, platinum-coated titanium cathode, silver/silver
chloride reference) electrochemical cell, with the anodic and cathodic chambers separated by a Nafion 117 membrane. Treatment
of nitrate and ammonium was tested with and without the presence of chloride in the waste. No significant difference was observed
in cathodic nitrate reduction with chloride present or absent. However, the presence of chloride in the solution favored overall
soluble nitrogen elimination upon oxidation. Increasing applied current increased production of undesirable byproducts (especially
chlorate). 相似文献
235.
236.
Margaret B. Williams Rebecca R.H. Michelsen Jessica L. Axson Laura T. Iraci 《Atmospheric environment (Oxford, England : 1994)》2010,44(9):1145-1151
The solubilities of acetone, ethanol and acetaldehyde in cold ternary solutions composed of 38.4–75.0 wt% sulfuric acid in water with additional dissolved organic material have been measured over the temperature range 214.4–238.5 K using a Knudsen cell reactor. The solubility of acetaldehyde in H2SO4/H2O is enhanced by an order of magnitude by the presence of ethanol or acetone. The reactive uptake of acetaldehyde is enhanced by the presence of formaldehyde in acid solution. No significant formation of acetals from ethanol with carbonyl partners was observed. The solubility of acetone is unaffected by the presence of ethanol in solution and vice versa. Only polymerization of small aldehydes offers a potentially significant route to the accretion of organic material into acidic particles in the upper troposphere. The acid-catalyzed polymerization of aldehydes, RC(H)O + R′C(H)O, proceeds through the hydrated forms of the aldehydes, is optimized at acidities around 40 wt% H2SO4, and can potentially accumulate significant amounts (>20%) of organic material by mass in upper tropospheric particles. 相似文献
237.
238.
Monitoring of ambient air PCDD/F levels in Portugal 总被引:3,自引:0,他引:3
As part of a monitoring program conducted by IDAD--Institute for Environment and Development and supported by regional municipal solid waste (MSW) management authorities, dioxin concentrations in ambient air were measured in three regions of Portugal: Porto, Lisbon and Madeira. These independent studies were performed with the intention of providing data as a basis for the evaluation of potential impacts of the operation of recently built MSW incinerators. Thus, 170 samples were collected in nine different sites from January 1999 till present. The measured levels revealed an extremely variable content of PCDDs/PCDFs depending both on the area and the season of the year. Samples taken in Porto and Lisbon reveal a similar homologue structure even if concentrations measured in the Porto region are significantly greater. Data from Madeira is characteristic of a remote site with some of the congeners concentrations below the detection limit. 相似文献
239.
Breast milk samples from 40 first-time mothers from the Pacific Northwest of the US and Canada were analyzed for polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs). Total PBDEs (summation operator PBDEs), calculated by summing values for the 12 PBDEs congeners analyzed, ranged from 6 to 321 ppb (lipid weight) (mean=96 ppb; median=50 ppb). In approximately 40% of the women (15/40), summation operator PBDEs>100 ppb lw in their milk, and four samples had levels >250 ppb lw. PBDE 47 was the dominant congener in most samples, whereas PBDE 153 was predominant in a few (3/40). summation operator PCBs were calculated by summing values for the 82 PCB congeners analyzed, and ranged from 49 to 415 ppb (lipid weight) (mean=147 ppb; median=126 ppb). approximately 30% of the mothers (13/40) have summation operator PBDEs> summation operator PCBs in their milk samples, and approximately 65% (25/40) have BDE 47>PCB 153 in breast milk samples, with BDE 47 averaging 3-fold greater levels than PCB 153. Clearly, the lower brominated PBDEs are surpassing PCBs as a major environmental concern in North America, and are likely affecting significant portions of the populations in these regions. PBDEs have become a major persistent organic pollutant. However, there are no positive correlations between levels of summation operator PBDEs and summation operator PCBs, or between levels of PBDE 47 and PCB 153, suggesting there may be some differences in exposure pathways for PBDEs and PCBs in humans. 相似文献
240.
Bassett Imogen E. McNaughton Ellery J. Plank Gemma D. Stanley Margaret C. 《Environmental management》2020,66(1):30-41
Environmental Management - Cat ownership is increasing globally, representing a growing threat to urban wildlife. Although some cities have policies and strategies for managing owned cats, the... 相似文献