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851.
Linda Westman James Patterson Rachel Macrorie Christopher J. Orr Catherine M. Ashcraft Vanesa Castn Broto Dana Dolan Mukesh Gupta Jeroen van der Heijden Thomas Hickmann Robert Hobbins Marielle Papin Enora Robin Christina Rosan Jonas Torrens Robert Webb 《Ambio》2022,51(6):1402
The crises that cities face—such as climate change, pandemics, economic downturn, and racism—are tightly interlinked and cannot be addressed in isolation. This paper addresses compound urban crises as a unique type of problem, in which discrete solutions that tackle each crisis independently are insufficient. Few scholarly debates address compound urban crises and there is, to date, a lack of interdisciplinary insights to inform urban governance responses. Combining ideas from complex adaptive systems and critical urban studies, we develop a set of boundary concepts (unsettlement, unevenness, and unbounding) to understand the complexities of compound urban crises from an interdisciplinary perspective. We employ these concepts to set a research agenda on compound urban crises, highlighting multiple interconnections between urban politics and global dynamics. We conclude by suggesting how these entry points provide a theoretical anchor to develop practical insights to inform and reform urban governance. 相似文献
852.
Christopher J. Hoard Ralph J. Haefner William D. Shuster Rachel L. Pieschek Stephanie Beeler 《Journal of the American Water Resources Association》2020,56(1):82-99
A goal in urban water management is to reduce the volume of stormwater runoff in urban systems and the effect of combined sewer overflows into receiving waters. Effective management of stormwater runoff in urban systems requires an accounting of various components of the urban water balance. To that end, precipitation, evapotranspiration (ET), sewer flow, and groundwater in a 3.40‐hectare sewershed in Detroit, Michigan were monitored to capture the response of the sewershed to stormwater flow prior to implementation of stormwater control measures. Monitoring results indicate that stormflow in sewers was not initiated unless rain depth was 3.6 mm or greater. ET removed more than 40% of the precipitation in the sewershed, whereas pipe flow accounted for 19%–85% of the losses. Flows within the sewer that could not be associated with direct precipitation indicate an unexpected exchange of water between the leaky sewer and the groundwater system, pathways through abandoned or failing residential infrastructure, or a combination of both. Groundwater data indicate that groundwater flows into the leaky combined sewer rather than out. This research demonstrates that urban hydrologic fluxes can modulate the local water cycle in complex ways which affect the efficiency of the wastewater system, effectiveness of stormwater management, and, ultimately, public health. 相似文献
853.
Many conservation conflicts are scientifically complex yet are rooted in value conflicts, which result in an impasse. Additional biological information alone is insufficient to resolve this type of conflict. Conceptual models that articulate the material aspects of a system are increasingly used to identify areas where parties disagree. Yet, modeling processes typically follow the conveners’ rules for discussing and assessing the topic, which can exacerbate conflict. Researchers have identified a need for processes that require participants to reflect on the limits of their own philosophical assumptions and acknowledge other perspectives. Cultural models are a promising tool for this purpose because they include nonmaterial beliefs, morals, and values that guide people's understanding of how to interact with an issue, sometimes subconsciously. We explored how cultural models used with conceptual models can improve understanding of value conflicts and used outdoor cat management as a case study. We conducted interviews and focus group discussions with wildlife conservation and cat welfare professionals involved in outdoor cat policy discussions in Hawaii and Washington, D.C. From these conversations, we developed a conceptual model of the outdoor cat management system and cultural models that led stakeholders to weigh elements of the conceptual model differently. Although wildlife conservation professionals generally spoke about outdoor cats as invasive species, cat welfare professionals spoke about them as homeless pets. These conflicting conceptualizations of what an outdoor cat is may help explain the root of many long-standing disagreements. Examining how and when stakeholders invoke different cultural models allowed us to identify management actions that work with, rather than challenge, those models. Dialogue that embraces conflicting cultural models can be difficult and uncomfortable, but has great potential to overcome conservation impasse and achieve lasting conservation results. 相似文献
854.
H. Christopher Frey Alper Unal Nagui M. Rouphail James D. Colyar 《Journal of the Air & Waste Management Association (1995)》2013,63(8):992-1002
Abstract A study design procedure was developed and demonstrated for the deployment of portable onboard tailpipe emissions measurement systems for selected highway vehicles fueled by gasoline and E85 (a blend of 85% ethanol and 15% gasoline). Data collection, screening, processing, and analysis protocols were developed to assure data quality and to provide insights regarding quantification of real-world intravehicle variability in hot-stabilized emissions. Onboard systems provide representative real-world emissions measurements; however, onboard field studies are challenged by the observable but uncontrollable nature of traffic flow and ambient conditions. By characterizing intravehicle variability based on repeated data collection runs with the same driver/vehicle/route combinations, this study establishes the ability to develop stable modal emissions rates for idle, acceleration, cruise, and deceleration even in the face of uncontrollable external factors. For example, a consistent finding is that average emissions during acceleration are typically 5 times greater than during idle for hydrocarbons and carbon dioxide and 10 times greater for nitric oxide and carbon monoxide. A statistical method for comparing on-road emissions of different drivers is presented. Onboard data demonstrate the importance of accounting for the episodic nature of real-world emissions to help develop appropriate traffic and air quality management strategies. 相似文献
855.
Christopher M. Beck Alison Geyh Arjun Srinivasan Patrick N. Breysse Peyton A. Eggleston 《Journal of the Air & Waste Management Association (1995)》2013,63(10):1256-1264
Abstract In response to community concerns, the air quality impact of imploding a 22-story building in east Baltimore, MD, was studied. Time- and space-resolved concentrations of indoor and outdoor particulate matter (PM) (nominally 0.5–10 µm) were measured using a portable nephelometer at seven and four locations, respectively. PM10 levels varied in time and space; there was no measurable effect observed upwind of the implosion. The downwind peak PM10 levels varied with distance (54,000–589 µg/m3) exceeding pre-implosion levels for sites 100 and 1130 m 3000- and 20-fold, respectively. Estimated outdoor 24-hr integrated mass concentrations varied from 15 to 72 µg/m3. The implosion did not result in the U.S. Environmental Protection Agency (EPA) National Ambient Air Quality Standard (NAAQS) for PM10 being exceeded. X-ray fluorescence analysis indicated that the elemental composition was dominated by crustal elements: calcium (57%), silicon (23%), aluminum (7.6%), and iron (6.1%). Lead was above background but at a low level (0.17 µg/m3). Peak PM10 concentrations were short-lived; most sites returned to background within 15 min. No increase in indoor PM10 was observed even at the most proximate 250 m location. These results demonstrate that a building implosion can have a severe but short-lived impact on community air quality. Effective protection is offered by being indoors or upwind. 相似文献
856.
Global warming is breeding social conflict: The subtle impact of climate change threat on authoritarian tendencies 总被引:1,自引:0,他引:1
Immo Fritsche J. Christopher CohrsThomas Kessler Judith Bauer 《Journal of environmental psychology》2012,32(1):1-10
Climate change can increase societies’ propensity to conflict by changes in socio-structural conditions (e.g., resource scarcity, migration). We propose an additional, subtle, and general effect of climate change threat via increases in authoritarian attitudes. Three studies in Germany and the UK support this suggestion. Reminding participants of the adverse consequences climate change may have for their country increased the derogation of societal groups that may threaten the collective (e.g., criminals) as well as general authoritarian attitudes. Salient climate change threats also led to system justification and approval of system supporting groups (e.g., judges) in those people who were highly identified with their nation. We discuss the implications of these findings for the explanation of authoritarian attitudes and the question of how societies may cope with the subtle social psychological effects of climate change. 相似文献
857.
Christopher E. Barthel Jr. 《Journal of the Air & Waste Management Association (1995)》2013,63(12):950-954
In today's world of misunderstanding, confusion, and conflict man is sadly in need of some force for pulling together and unifying his efforts for peace, progress, safety, and health upon his native Planet. During the latter days of the Conference, when delegates from large nations and small nations and rich nations and poor nations were working tirelessly to reach agreement on a Declaration on the Human Environment, and during the closing hours of the Conference when the Declaration was approved by unanimous vote, it appeared to many persons that the environment might well be such a unifying force for mankind. Throughout the early days of the Stockholm sessions, the conflict of ideologies and political Dr. Barthel is the Director of the Institute of Environmental Sciences, Miami University, Oxford, Ohio 45056. He attended the Stockholm Conference as an accredited representative of the International Union of Air Pollution Associations. principles and severe disagreement on specific issues relating to the environment were all too apparent, but through pertinacity and splendid Conference leadership, differences were resolved and wide-scale agreements reached. 相似文献
858.
Trails created by off-road vehicles (ORV) in boreal lowlands are known to cause local impacts, such as denuded vegetation,
soil erosion, and permafrost thaw, but impacts on stream and watershed processes are less certain. In Wrangell-St. Elias National
Park and Preserve (WRST), Alaska, ORV trails have caused local resource damage in intermountain lowlands with permafrost soils
and abundant wetlands and there is a need to know whether these impacts are more extensive. Comparison of aerial photography
from 1957, 1981, and 2004 coupled with ground surveys in 2009 reveal an increase in trail length and number and show an upslope
expansion of a trail system around points of stream channel initiation. We hypothesized that these impacts could also cause
premature initiation and headward expansion of channels because of lowered soil resistance and greater runoff accumulation
as trails migrate upslope. Soil monitoring showed earlier and deeper thaw of the active layer in and adjacent to trails compared
to reference sites. Several rainfall-runoff events during the summer of 2009 showed increased and sustained flow accumulation
below trail crossings and channel shear forces sufficient to cause headward erosion of silt and peat soils. These observations
of trail evolution relative to stream and wetland crossings together with process studies suggest that ORV trails are altering
watershed processes. These changes in watershed processes appear to result in increasing drainage density and may also alter
downstream flow regimes, water quality, and aquatic habitat. Addressing local land-use disturbances in boreal and arctic parklands
with permafrost soils, such as WRST, where responses to climate change may be causing concurrent shifts in watershed processes,
represents an important challenge facing resource managers. 相似文献
859.
Koffi L. Dagnon Christopher Thellen Jo Ann Ratto Nandika A. D’Souza 《Journal of Polymers and the Environment》2010,18(4):510-522
The degradation of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P(3HB-co-4HB)) coated brown Kraft paper and its components in a constructed soil environment was investigated. Soil burial tests were
carried out over 8 weeks. Weight loss measurements, photographic analysis, environmental scanning electron microscopy (ESEM),
dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC) were conducted to assess the physical, structural,
mechanical and thermal behavior before and after the soil burial test. Paper showed the highest physical degradation and weight
loss. With respect to the control samples, the stiffness of the partially degraded samples decreased. The overall crystallinity
of the biopolymer and the coated paper was affected significantly by burial. The pure biopolymer’s weight loss was substantially
enhanced when coated on paper. This result reveals a possible increased microbial population in the coated paper relative
to the pure biopolymer. 相似文献
860.
Kevin A. Schug Theodore R. Skingel Sandra E. Spencer Carlos A. Serrano Cuong Q. Le Christopher A. Schug Theodore W. Valenti Jr. Bryan W. Brooks Laura D. Mydlarz James P. Grover 《Journal of the American Water Resources Association》2010,46(1):33-44
Schug, Kevin A., Theodore R. Skingel, Sandra E. Spencer, Carlos A. Serrano, Cuong Q. Le, Christopher A. Schug, Theodore W. Valenti, Jr., Bryan W. Brooks, Laura D. Mydlarz, and James P. Grover, 2010. Hemolysis, Fish Mortality, and LC-ESI-MS of Cultured Crude and Fractionated Golden Alga (Prymnesium parvum). Journal of the American Water Resources Association (JAWRA) 46(1):33-44. DOI: 10.1111/j.1752-1688.2009.00389.x Abstract: Erythrocyte lysis and fish mortality assays, in combination with high performance liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) analysis, were investigated for bioassay-guided fractionation of cultured golden alga (Prymnesium parvum). Intracellular constituents from isolated cell pellets and extracellular supernatant growth medium were fractionated by a variety of common separation modes, including reversed phase and normal phase solid phase extraction step fractionation procedures. For reversed phase fractionation of extracellular growth medium, one fraction was obtained that displayed hemolytic activity and adversely affected fish survival. Effective dose concentrations for this sample were similar in both assays and the LC-ESI-MS analysis of the fraction showed a number of mass spectral signals which were distinct to this fraction. Fractions obtained from separation of an ethanol extract of the lyophilized cell pellet provided one sample that was highly hemolytic, but not toxic to fish. Discrepancies such as this, along with notable fish behavioral responses from other nonhemolytic cell pellet fractions, problems with the use of unbonded silica gel for fractionation, and misleading mass spectral signatures are interesting in the context of our current understanding of P. parvum toxicity and remain to be investigated further. This work provides an account of ongoing research aimed toward comprehensive elucidation of toxic constituents produced by golden alga for the purpose of providing a better understanding and means to potentially remediate the ecological impact of this harmful bloom organism. 相似文献