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281.
282.
Summary Despite of decades of successful worldwide use of magnetic/electromagnetic field therapy, the answer to the question of possible
mechanisms of action is still lacking. Scientific reports of successful therapeutic use of magnetic/electromagnetic fields
are worldwide; however, our understanding of the underlying mechanism is limited. This paper presents a new hypothesis that
therapeutic benefit of magnetic fields might result from effects that originated on the level of important systems in human
body. It is known now that the life is an electromagnetic event in aqueous medium. Therefore, an appropriate choice of magnetic
and/or electromagnetic field may be expected to initiate systemic changes that result in efficacious effects distant from
the point of application. Observations of this phenomenon have been reported in at least two forms: (1) neutralization of
the pain experience distant to the point of magnetic field exposure; and, (2) various alterations of T-lymphocytes in response
to pain and to magnetic fields. Extrapolating these observations to the level of blood-vessel system, one might hypothesize
that a “healthy” cell does not respond as readily to the applied fields as do abnormal cells (which are in a disease or injury
state). 相似文献
283.
McFarland MJ Nelson TM Rasmussen SL Palmer GR Olivas AC 《Journal of the Air & Waste Management Association (1995)》2005,55(3):302-308
All U.S. Department of Defense (DoD) facilities are required under Executive Order (EO) 13148, "Greening the Government through Leadership in Environmental Management," to establish quality-based environmental management systems (EMSs) that support environmental decision-making and verification of continuous environmental improvement by December 31, 2005. Compliance with EO 13148 as well as other federal, state, and local environmental regulations places a significant information management burden on DoD facilities. Cost-effective management of environmental data compels DoD facilities to establish robust database systems that not only address the complex and multifaceted environmental monitoring, record-keeping, and reporting requirements demanded by these rules but enable environmental management decision-makers to gauge improvements in environmental performance. The Enterprise Environmental Safety and Occupational Health Management Information System (EESOH-MIS) is a new electronic database developed by the U.S. Air Force to manage both the data needs associated with regulatory compliance programs across its facilities as well as the non-regulatory environmental information that supports installation business practices. The U.S. Air Force, which has adopted the Plan-Do-Check-Act methodology as the EMS standard that it will employ to address EO 13148 requirements. 相似文献
284.
Global maps of natural hazard occurrence and risk are useful tools for policy makers and international development organizations. The ranking of countries or regions by relative exposure provides a metric for prioritizing strategies for natural hazard mitigation and risk management, and for planning for response and recovery. However, the calculations underlying global natural hazard risk mapping depend on the availability and quality of geophysical and socio-economic data, which are highly variable from region to region, and may impede the application of global rankings to regional decision making. This paper summarizes a recent synthesis of natural hazard occurrence, exposure and loss data—the World Bank's “Hotspots” project—and describes the advantages and difficulties in such an approach. Several suggestions for more highly resolved, regional and sub-national analyses are made. 相似文献
285.
Susan K. Rope W. John Arthur III Timothy H. Craig Erica H. Craig 《Environmental monitoring and assessment》1988,10(1):1-24
Concentrations of thirty elements were measured in strong-acid extracts of soil, sagebrush (Artemisia tridentata spp.) leaves and perennial grass from the Idaho National Engineering Laboratory (INEL) and two reference sites in southern Idaho. A bicarbonate-chelating extract of soil was used to estimate plant-available concentrations. The results provide baseline data prior to start-up of a coal-fired steam generation facility on the INEL and other developments in the region. In addition, existing impact from effluents from thirty years of a nuclear fuel reprocessing facility on the INEL was evaluated. Based on the spatial distribution of element concentrations, as well as comparison with references sites, we conclude that concentrations of Zn, and perhaps Ni, Cd, and V, are currently elevated around the fuel reprocessing facility. The spatial distribution of these elements is similar to that of 137Cs in soil, a radionuclide which is emitted by the facility. Sagebrush and soil appear more responsive than perennial grass for long-term monitoring of element concentrations in this semi-arid environment. 相似文献
286.
Shishan Hu Scott Fruin Kathleen Kozawa Steve Mara Suzanne E. Paulson Arthur M. Winer 《Atmospheric environment (Oxford, England : 1994)》2009,43(16):2541-2549
We have observed a wide area of air pollutant impact downwind of a freeway during pre-sunrise hours in both winter and summer seasons. In contrast, previous studies have shown much sharper air pollutant gradients downwind of freeways, with levels above background concentrations extending only 300 m downwind of roadways during the day and up to 500 m at night. In this study, real-time air pollutant concentrations were measured along a 3600 m transect normal to an elevated freeway 1–2 h before sunrise using an electric vehicle mobile platform equipped with fast-response instruments. In winter pre-sunrise hours, the peak ultrafine particle (UFP) concentration (~95 000 cm?3) occurred immediately downwind of the freeway. However, downwind UFP concentrations as high as ~40 000 cm?3 extended at least 1200 m from the freeway, and did not reach background levels (~15 000 cm?3) until a distance of about 2600 m. UFP concentrations were also elevated over background levels up to 600 m upwind of the freeway. Other pollutants, such as NO and particle-bound polycyclic aromatic hydrocarbons, exhibited similar long-distance downwind concentration gradients. In contrast, air pollutant concentrations measured on the same route after sunrise, in the morning and afternoon, exhibited the typical daytime downwind decrease to background levels within ~300 m as found in earlier studies. Although pre-sunrise traffic volumes on the freeway were much lower than daytime congestion peaks, downwind UFP concentrations were significantly higher during pre-sunrise hours than during the daytime. UFP and NO concentrations were also strongly correlated with traffic counts on the freeway. We associate these elevated pre-sunrise concentrations over a wide area with a nocturnal surface temperature inversion, low wind speeds, and high relative humidity. Observation of such wide air pollutant impact area downwind of a major roadway prior to sunrise has important exposure assessment implications since it demonstrates extensive roadway impacts on residential areas during pre-sunrise hours, when most people are at home. 相似文献
287.
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289.
The study examined the relationships between four career concerns (Personal Success, Organizational Involvement, Skill Development and Autonomy) and two categories of political tactics in organizations (Hierarchical Tactics and Networking Tactics) in a sample of management school alumni. Career concerns were not related to the employment of hierarchical tactics but were strongly related to the use of networking tactics. ‘External’ career concerns of personal success and organizational involvement were more strongly related to political behavior than ‘internal’ career concerns of skill development and autonomy. Organization size was significantly related to the use of hierarchical tactics but not to the use of networking tactics. Type of organization structure (mechanistic versus organic) did not have a direct effect on political behavior but moderated the relationships between career concerns and political tactics. These relationships were stronger in organic than in mechanistic organizations. 相似文献
290.