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111.
E.?P.?BadásEmail author J.?Martínez J.?Rivero-de Aguilar C.?Ponce M.?Stevens S.?Merino 《Die Naturwissenschaften》2018,105(1-2):17
Carry-over effects refer to processes that occur in one season and influence fitness in the following. In birds, two costly activities, namely reproduction and moult, are restricted to a small time window, and sometimes overlap. Thus, colour in newly moulted feathers is likely to be affected by the costs of reproduction. Using models of bird vision we investigated male colour change in a free-living population of blue tits (Cyanistes caeruleus) in three sampling occasions: spring 1, winter and spring 2. We related crown, tail, breast and cheek feather colouration after the moult (winter) to the intensity of infections by blood parasites during reproduction (spring 1). In the following spring (spring 2), we explored mating patterns with respect to changes in feather colour (springs 1 vs. 2). Males that were less intensely infected by the malaria parasite Plasmodium while breeding showed purer white cheek feathers in winter, which may indicate higher feather quality. Increased brightness in the white cheek was associated with better body condition during reproduction. In the following season, males with brighter cheeks paired with females that had noticeably brighter cheek patches compared to the male’s previous mate. These results suggest that the conditions experienced during reproduction are likely to affect moult and thus feather colouration, at least in the white patch. High quality individuals may allocate resources efficiently during reproduction increasing future reproductive success through variation in mating patterns. Carry-over effects from reproduction might extend not only to the non-breeding phase, but also to the following breeding season. 相似文献
112.
Rien E. van Wijk Michael Schaub Steffen Hahn Natalia Juárez-García-Pelayo Björn Schäfer Lukáš Viktora Manuel Martín-Vivaldi Marko Zischewski Silke Bauer 《Die Naturwissenschaften》2018,105(7-8):42
The annual cycle of migrating birds is shaped by their seasonal movements between breeding and non-breeding sites. Studying how migratory populations are linked throughout the annual cycle—migratory connectivity, is crucial to understanding the population dynamics of migrating bird species. This requires the consideration not only of spatial scales as has been the main focus to date but also of temporal scales: only when both aspects are taken into account, the degree of migratory connectivity can be properly defined. We investigated the migration behaviour of hoopoes (Upupa epops) from four breeding populations across Europe and characterised migration routes to and from the breeding grounds, location of non-breeding sites and the timing of key migration events. Migration behaviour was found to vary both within and amongst populations, and even though the spatial migratory connectivity amongst the populations was weak, temporal connectivity was strong with differences in timing amongst populations, but consistent timing within populations. The combination of diverse migration routes within populations and co-occurrence on the non-breeding grounds between populations might promote exchange between breeding populations. As a result, it might make hoopoes and other migrating bird species with similar strategies more resilient to future habitat or climatic changes and stabilise population trends. 相似文献
113.
Beatriz Fernández-Muñiz José Manuel Montes-Peón Camilo José Vázquez-Ordás 《Safety Science》2009,47(7):980-991
Occupational accidents severely deteriorate human capital, and hence negatively affect the productivity and competitiveness of countries. But despite this, we still observe a scarcity of preventive practices, an unsatisfactory management commitment and an absence of safety culture among Spanish firms. The result is evident in firms’ high accident rates. This situation is a consequence of the general belief among firms that investing in safety is a cost, and hence has negative repercussions for their competitiveness. The current work aims to identify good practices in safety management, and analyse the effect of these practices on a set of indicators of organisational performance. For this, we first carry out an exhaustive literature review, and then formulate a series of hypotheses. We then test the proposed model on a sample of 455 Spanish firms. Our findings show that safety management has a positive influence on safety performance, competitiveness performance, and economic-financial performance. Hence they provide evidence of the compatibility between worker protection and corporate competitiveness. 相似文献
114.
Guiomar Rotllant Francisco Javier Moyano Mireia Andrés Alicia Estévez Manuel Díaz Enric Gisbert 《Marine Biology》2010,157(10):2215-2227
The effect of food deprivation on larval performance of the spider crab Maja brachydactyla was studied in terms of survival, moulting capacity, size, weight and enzymatic activities. Five feeding treatments that
differed in the initial age of first feeding larvae (fed from hatching, 2, 4 and 6 days post-hatching and unfed) were tested
for 20 days. Newly hatched larvae kept without food supply lasted for 10 days and did not moult; with 50% survival observed
at 6 days post-hatching. Larvae (zoea I stage) were only able to tolerate 2 days of food deprivation after the onset of exogenous
feeding without their performance being compromised. Multivariate analyses suggest that digestive enzyme activities may be
good indicators of the nutritional condition of larvae. 相似文献
115.
Wenjun Qin Manuel Dekermenjian 《Journal of the Air & Waste Management Association (1995)》2013,63(8):1177-1183
Abstract Loss of filtration efficiency in a fabric filter baghouse is typically caused by bag failure, in one form or another. The degree of such failure can be as minor as a pinhole leak or as major as a fully involved baghouse fire. In some cases, local air pollution regulations or federal hazardous waste laws may require estimation of the total quantity of particulate matter released to the environment as a result of such failures. In this paper, a technique is presented for computing the dust loading in the baghouse exhaust when one or more bags have failed. The algorithm developed is shown to be an improvement over a previously published result, which requires empirical knowledge of the variation in baghouse pressure differential with bag failures. An example calculation is presented for a bag-house equipped with 200 bags. The prediction shows that a small percentage of failed bags can cause a relatively large proportion of the gas flow to bypass the active bags, which, in turn, leads to high outlet dust loading and low overall collection efficiency from the baghouse. 相似文献
116.
Environmental Chemistry Letters - The increasing bacterial resistance from antibiotic overuse has fostered the search for novel antimicrobial strategies. In particular, bacterial systems involving... 相似文献
117.
Emily A. Botts Genevieve Pence Stephen Holness Kerry Sink Andrew Skowno Amanda Driver Linda R. Harris Philip Desmet Boyd Escott Mervyn Lötter Jeanne Nel Tammy Smith Fahiema Daniels Samuel Sinclair Warrick Stewart Jeffrey Manuel 《Conservation biology》2019,33(6):1235-1246
Systematic conservation planning is intended to inform spatially explicit decision making. Doing so requires that it be integrated into complex regulatory and governance processes, and there are limited instances where this has been achieved effectively. South Africa is a global leader in the application of conservation plans, the outputs of which are widely used for spatial planning and decision making in many spheres of government. We aimed to determine how conservation planning in the country progressed from theory to implementation, and to identify practical actions that enabled this transition, by assessing temporal trends in the characteristics of conservation plans (1990–2017, n = 94). Since 2010 conservation planning has entered an operational period characterized by government leadership of plans, administrative rather than ecological planning domains, decreasing size of planning units, increasing emphasis on end-user products, and scheduled revision of plans. Key actions that enabled this progression include transitioning leadership of plans from scientists to practitioners, building capacity within implementing agencies, creating opportunities to integrate plans in legislative processes, establishing a strong community of practice, adopting implementation-focused methods, and balancing standardization with innovation. Learning from this model will allow other countries, particularly those with a similar megadiverse, developing context, to operationalize conservation planning into spatial planning and decision making. 相似文献
118.
Cristal Fernández-Gómez José Antonio López-López Victor Matamoros Sergi Díez Manuel García-Vargas Carlos Moreno 《Environmental monitoring and assessment》2013,185(4):3209-3218
In the lower Guadalquivir river basin, a system stressed by a wide variety of anthropogenic activities, eight pesticides (four triazines, two chloroacetanilide herbicides, one organochlorine, and one organophosphorus insecticide); and four emerging pollutants (two personal care products, one organophosphorous flame retardant, and one xanthine alkaloid) were analyzed in river water during a 2-year monitoring program, and after rain episodes. Samples were extracted using the solid phase extraction (SPE) technique prior to determination of compounds using gas chromatograph coupled to a mass spectrometer detector. Except for caffeine, recoveries were mostly above 80 %, while limits of detection and quantification were in the low nanograms per liter level (except for dimethoate). Terbuthylazine, simazine (triazine herbicides), and dimethoate (organophosphorus insecticide), present in agrochemicals, were predominant in the river water, although concentrations were below the quality standards established by the EU Water-Framework-Directive. A general trend to increase concentration was observed after rain events, in particular for pesticides, possibly as a consequence of surface runoff. 相似文献
119.
Jose A. Manzanilla-Cano Manuel H. Barcelo-Quintal Tania I. Coral-Martinez 《Journal of environmental science and health. Part. B》2013,48(7):546-552
Photochemical degradation of methylparathion (O,O,-dimethyl O-4 nitrophenylphosphorothioate) in the presence of humic acid between pH 2 and 7 was monitored by differential pulse polarography. Humic acid was not electro-active under the experimental conditions used in this study. Only the pesticide and its main degradation product at pH 2 exhibited polarographic signals. Photolysis of methylparathion in acid media was sensitized by humic acid since the pesticide did not degrade in the absence of this compound. Methylparathion degradation in the presence of humic acid was observed at each of the studied pHs. The reaction was first-order with rate constant values ranging from 2 × 10?3 to 6.3 × 10?3 min?1. 相似文献
120.
Gerald Fischer Tina Frohne Lydia Gerharz Margit Hildebrandt Otto Klemm Katrin Mildenberger Carsten Nording Ingo Rehberger Manuel Schiffer Christos Stephan Voulkoudis 《Environmental Sciences Europe》2006,18(3):155-163