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361.
Alice A. Han Emily B. Fabyanic Julie V. Miller Maren S. Prediger Nicole Prince Julia A. Mouch Jonathan Boyd 《Environmental monitoring and assessment》2017,189(4):190
Thousands of gallons of industrial chemicals, crude 4-methylcyclohexanemethanol (MCHM) and propylene glycol phenyl ether (PPh), leaked from industrial tanks into the Elk River in Charleston, West Virginia, USA, on January 9, 2014. A considerable number of people were reported to exhibit symptoms of chemical exposure and an estimated 300,000 residents were advised not to use or drink tap water. At the time of the spill, the existing toxicological data of the chemicals were limited for a full evaluation of the health risks, resulting in concern among those in the impacted regions. In this preliminary study, we assessed cell viability and plasma membrane degradation following a 24-h exposure to varying concentrations (0–1000 μM) of the two compounds, alone and in combination. Evaluation of different cell lines, HEK-293 (kidney), HepG2 (liver), H9c2 (heart), and GT1-7 (brain), provided insight regarding altered cellular responses in varying organ systems. Single exposure to MCHM or PPh did not affect cell viability, except at doses much higher than the estimated exposure levels. Certain co-exposures significantly reduced metabolic activity and increased plasma membrane degradation in GT1-7, HepG2, and H9c2 cells. These findings highlight the importance of examining co-exposures to fully understand the potential toxic effects. 相似文献
362.
Spoors JA Winger LA Siew LK Dessi JL Jennens L Self CH 《Journal of environmental monitoring : JEM》2002,4(6):917-921
To date, no ligand binding assay has been described for the carbamate herbicide asulam, although a variety of physical methods, dependent on pre-concentration of water samples, have been documented for its assessment. However, asulam is increasingly used in sensitive agricultural areas, and statutory regulations concerning its monitoring will undoubtedly become more stringent. Antibodies are optimal partners in ligand binding assays, but it is commonly understood by immunological researchers that where no antibody reactive with a particular antigen has yet been described, the immunogenicity of the antigen may be particularly restricted. By the expedient of employing a specialised approach to final immunisation with an asulam-protein conjugate, prior to the immortalisation of a specific anti-asulam antibody-producing cell, we have succeeded in generating a monoclonal antibody reactive specifically with asulam that can be configured in a convenient immunoassay. This antibody may be used flexibly in a number of ways: small sample volumes of 10 microl can be assessed to sensitivities of 4.35 x 10(-7) M (10 microg L(-1)) while avoiding discrepancies contributed by the assay matrix; this antibody-based assay can also be formatted to deliver sensitivities at levels stipulated by regulatory authorities (e.g., 4.35 x 10(-9) M or 0.1 microg L(-1)) directly from a water sample, without prior pre-concentration. 相似文献
363.
Julia Delingat Franz Bairlein Anders Hedenström 《Behavioral ecology and sociobiology》2008,62(7):1069-1078
Behaviour on migration was often suggested to be selected for time-minimising strategies. Current optimality models predict
that optimal fuel loads at departure from stopover sites should increase with increasing fuel deposition rates. We modified
such models for the special case of the east Atlantic crossing of the Northern Wheatear (Oenanthe oenanthe). From optimality theory, we predict that optimal time-minimising behaviour in front of such a barrier should result in a
positive correlation between fuel deposition rates and departure fuel loads only above a certain threshold, which is the minimum
fuel load (f
min) required for the barrier crossing. Using a robust range equation, we calculated the minimum fuel loads for different barrier
crossings and predict that time-minimising wheatears should deposit a minimum of 24% fuel in relation to lean body mass (m
0
) for the sea crossing between Iceland and Scotland. Fuel loads of departing birds in autumn in Iceland reached this value
only marginally but showed positive correlation between fuel deposition rate (FDR) and departure fuel load (DFL). Birds at
Fair Isle (Scotland) in spring, which were heading towards Iceland or Greenland, were significantly heavier and even showed
signs of overloading with fuel loads up to 50% of lean body mass. Departure decisions of Icelandic birds correlated significantly
with favourable wind situations when assuming a migration direction towards Spain; however, the low departure fuel loads contradict
a direct non-stop flight. 相似文献
364.
365.
Kitchen Dawn M. Seyfarth Robert M. Fischer Julia Cheney Dorothy L. 《Behavioral ecology and sociobiology》2003,53(6):374-384
Adult male baboons (Papio cynocephalus) give loud two-syllable 'wahoo' calls during dawn choruses, interactions between groups, when chasing females, and in aggressive interactions with other males. These 'contest' wahoos are acoustically different from 'alarm' wahoos given to predators. In a study of free-ranging baboons in the Okavango Delta, Botswana, we found no significant correlations between the acoustic features of wahoos and adult male size; however, acoustic features were correlated with male dominance rank, age, and calling bout length. Here we show that other measures of calling behavior also appear to function as honest indicators of stamina and competitive ability. High-ranking males were more likely than middle- or low-ranking males to participate in wahoo bouts. They called at significantly higher rates, and their bouts were longer and contained more calls. All males were significantly more likely to participate in wahoo bouts with another male if their opponent's rank was similar to their own. Bouts involving males of similar ranks were longer, contained more wahoos, and involved calling at higher rates, than other bouts. In contests between males of similar ranks, the subordinate and dominant were equally likely to end the bout, whereas in contests involving males of disparate ranks, subordinates were significantly more likely to end the bout. Bouts involving males of similar rank were significantly more likely than others to escalate and result in physical fighting. 相似文献
366.
Kathryn B. McNamara Julia L. McKenzie Mark A. Elgar Therésa M. Jones 《Behavioral ecology and sociobiology》2012,66(8):1141-1147
Male mating status can affect female reproductive output if male ejaculate investment declines over consecutive matings. Accordingly, females are predicted to mate preferentially with virgin males. In mildly polyandrous lepidopterans, female fitness is less affected by reduced male investment than in more polyandrous species, and so the predictions for female mating preferences are less clear. We examined female mating preferences in the mildly polyandrous almond moth, Cadra cautella, in which ejaculate size does not affect female reproductive output. First, we allowed females to mate with virgin or once-mated males, in which the males were presented individually or simultaneously. We recorded the latency to mating and, in the case of the simultaneously presented trials, the identity of the successful, copulating male. We found that females mated more frequently with mated males (when simultaneously presented with both males), yet females did not differ in the time taken to initiate copulation with any male. We further examined if this mated male advantage was due to differential mate detection or locomotory behaviour of the male treatments. We tested the ability of virgin and mated males to locate a receptive female within a wind tunnel using long-distance pheromone cues and recorded their activity budget. We found no difference in the ability of mated or virgin males to locate or approach a receptive female, or in their activity levels. These data suggest a female preference for mated males in this species, a preference that may minimise other potential costs of mating. 相似文献
367.
Graham W. Prescott William J. Sutherland Daniel Aguirre Matthew Baird Vicky Bowman Jake Brunner Grant M. Connette Martin Cosier David Dapice Jose Don T. De Alban Alex Diment Julia Fogerite Jefferson Fox Win Hlaing Saw Htun Jack Hurd Katherine LaJeunesse Connette Felicia Lasmana Cheng Ling Lim Antony Lynam Aye Chan Maung Benjamin McCarron John F. McCarthy William J. McShea Frank Momberg Myat Su Mon Than Myint Robert Oberndorf Thaung Naing Oo Jacob Phelps Madhu Rao Dietrich Schmidt‐Vogt Hugh Speechly Oliver Springate‐Baginski Robert Steinmetz Kirk Talbott Maung Maung Than Tint Lwin Thaung Salai Cung Lian Thawng Kyaw Min Thein Shwe Thein Robert Tizard Tony Whitten Guy Williams Trevor Wilson Kevin Woods Alan D. Ziegler Michal Zrust Edward L. Webb 《Conservation biology》2017,31(6):1257-1270
Political and economic transitions have had substantial impacts on forest conservation. Where transitions are underway or anticipated, historical precedent and methods for systematically assessing future trends should be used to anticipate likely threats to forest conservation and design appropriate and prescient policy measures to counteract them. Myanmar is transitioning from an authoritarian, centralized state with a highly regulated economy to a more decentralized and economically liberal democracy and is working to end a long‐running civil war. With these transitions in mind, we used a horizon‐scanning approach to assess the 40 emerging issues most affecting Myanmar's forests, including internal conflict, land‐tenure insecurity, large‐scale agricultural development, demise of state timber enterprises, shortfalls in government revenue and capacity, and opening of new deforestation frontiers with new roads, mines, and hydroelectric dams. Averting these threats will require, for example, overhauling governance models, building capacity, improving infrastructure‐ and energy‐project planning, and reforming land‐tenure and environmental‐protection laws. Although challenges to conservation in Myanmar are daunting, the political transition offers an opportunity for conservationists and researchers to help shape a future that enhances Myanmar's social, economic, and environmental potential while learning and applying lessons from other countries. Our approach and results are relevant to other countries undergoing similar transitions. 相似文献
368.
Cell proliferation and apoptosis were investigated in tissues of two bivalve species, Arctica islandica from the German Bight (age of bivalves: 33–98 years) and Iceland (7–148 years) and Aequipecten opercularis from the English Channel (2–4 years). High proliferation rates (10% nuclei dividing) and apoptosis in tissues of A. opercularis were in line with high-energy throughput and reduced investment into antioxidant defence mechanisms in the scallop. In contrast,
cell turnover was slow (<1% nuclei dividing) in A. islandica and similar in mantle, gill and adductor muscle between young and old individuals. In the heart, cell turnover rates decreased
with age, which indicates less-efficient removal of damaged cells in ageing A. islandica. Cell turnover rates, mass specific respiration and antioxidant enzyme activities were similar in German Bight and Iceland
ocean quahog. Variable maximum life expectancies in geographically separated A. islandica populations are determined by extrinsic factors rather than by fundamental physiological differences. 相似文献
369.
370.
Community-based urban aquaponics enterprises represent a new model for how to blend local agency with scientific innovation to deliver food sovereignty (FS) in cities, re-engaging and giving urban communities more control over their food production and distribution. Little is known, however, about the factors and outcomes that determine the success or failure of these enterprises. This paper explores stakeholder experiences of building community-based urban aquaponics enterprises to understand the internal and external factors that impact on their success or failure. We draw upon existing FS, social enterprise and aquaponics literature, to identify factors in the related area of community-based urban agriculture. For exploring these factors, we use a comparative case study methodology for two cases in Milwaukee and Melbourne, conducting in-depth interviews with key stakeholders, exploring their relative contexts, objectives and structure. Based on these findings, we highlight the challenges and suggest relevant indicators for establishing an urban aquaponics enterprise. 相似文献