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991.
William?Zonta Axel?Mauroy Frederic?Farnir Etienne?ThiryEmail author 《Food and environmental virology》2016,8(4):275-282
Human noroviruses (HuNoV) are amongst the leading causes of acute non-bacterial gastroenteritis in humans and can be transmitted via person-to-person contact, via contact with contaminated surfaces or by consumption of contaminated food. Contaminated surfaces in healthcare settings contribute to the transmission of viruses. No-touch automated room disinfection systems might prevent such a spread of contamination and thus their virucidal effect needs to be evaluated. The aim of this study was to assess the efficacy of a nebulization system spraying hydrogen peroxide on two main surrogates of HuNoV, namely murine norovirus (MNV) and feline calicivirus (FCV). The viruses were dried on cover glasses and on stainless steel discs and exposed to nebulization. The number of infectious viral particles and genomic copies before and after the nebulization was compared. The efficacy in reducing infectivity of both surrogates was demonstrated. For the infectious viral titre of MNV and FCV, a log10 reduction factor ≥4.84 and 4.85 was observed after nebulization, respectively, for tests on cover glasses and ≥3.90 and 5.30, respectively, for tests on stainless steel discs. Only low reductions in genomic copy numbers were observed for both surrogates. The nebulization of hydrogen peroxide showed a clear virucidal effect on both HuNoV surrogates, MNV and FCV, on two different carriers and the use of nebulization should be promoted in complementarity with conventional disinfection methods in healthcare settings and food processing facilities to reduce viral load and spread of contamination. 相似文献
992.
Thomas?WinklerEmail author Wilfried?Winiwarter 《Mitigation and Adaptation Strategies for Global Change》2016,21(8):1181-1196
In the present paper, national and externally organized projections of greenhouse gas emissions for Austria were compared to gain insight on the underlying scenario data assumptions. National greenhouse gas emission trends extend until 2030, an assessment of European Union (EU) countries to 2050. In addition, data for 2000–2100 was extracted from the global emission database described by the Representative Concentration Pathways (RCP). By identifying trends in these projections, it was possible to produce (a) a long-term assessment of national scenarios until 2100, (b) an assessment of the ambition level toward national climate strategies, and (c) a standardized method to compare trends across countries. By extracting RCP data, Austrian’s methane, nitrous oxide, and carbon dioxide emissions up to 2100 could be projected for all sources as well as specific sectors. With respect to the RCP scenario emission data, national projections did not seem to employ the mitigation potentials available for the most stringent RCP scenario, RCP2.6. Comparing projections that supported the EU Climate Strategy 2030 with national projections revealed similar trends. Because RCP2.6 is the only scenario consistent with a 2 °C global warming target, and it is much more ambitious than any of the national or European projections, further measures will be required if Austria is to adequately contribute to this widely accepted policy goal. 相似文献
993.
Maria João Cruz Elisabeth Maria Rogier Robert Tiago Costa David Avelar Rui Rebelo Mário Pulquério 《Regional Environmental Change》2016,16(5):1293-1304
Assessing biodiversity vulnerability to future climate change is essential for developing robust adaptation strategies. A number of vulnerability assessment methodologies have been developed, from bioclimatic envelop models to more complex approaches that also consider biological traits and population status. However, the lack of comparative studies leaves the user to choose among the different methodologies without much guidance. This study applied three vulnerability assessment approaches to the Portuguese herpetofauna: (I) impact assessment approach based on bioclimatic models; (II) integrated vulnerability assessment approach, adding the evaluation of adaptive capacity to approach I; and (III) integrated vulnerability assessment and validation based on expert consultation. Results showed disagreement between the different approaches for 19 % of the species studied. Most differences were found between approach III and the two other approaches. All approaches showed advantages and limitations, the choice of a methodology being ultimately dependent on the study goals. Approach I has proven efficient to capture general vulnerability patterns. Approach II, although presenting results similar to approach I, allows for the identification of key factors affecting the species adaptive capacity and may be useful in tailoring adaptation measures. Approach III further allows us to identify knowledge gaps and to evaluate vulnerability when data availability or quality is reduced. Further, because this approach is based on an expert workshop, it has proven a perfect means to build on the vulnerability assessment results to identify indicator species and prioritize specific adaptation options. 相似文献
994.
995.
Rui Galhano dos Santos Patrícia Ventura João C. Bordado Maria M. Mateus 《Environmental Chemistry Letters》2017,15(3):453-458
The world has become dependent on petroleum as a feedstock for most products that we use in our daily lives. As an alternative, bio-refineries that transform biomass into biofuels and primary chemicals are emerging. Actually, many wastes are not fully recycled. For instance, potato peel is a cheap residue available from the potato industry. Up to now, potato peel has been used mostly for livestock feeding. Here, potato peel waste was subjected to direct acid liquefaction at 160 °C in 2-ethylhexanol and diethylene glycol using p-toluene sulfonic acid as catalyst. The product was characterized by infrared spectroscopy, chemical analysis, hydroxyl number and acid value. Results show that liquefaction was achieved in yields higher than 80%. The reactional profile shows two time zones, one comprising the process of liquefaction and one corresponding to the process of decomposition. Kinetics indicate that the liquefaction process occurs 1.9 times faster than the decomposition process. Overall, our findings show for the first time that, despite the water content, potato peel waste can be used to produce bio-oil. The products can be further used as fuels or refined chemicals such as levulinic acid, furfural, 5-hydroxyfurfural, dimethyl furfural and sugars in fermentation processes. 相似文献
996.
997.
Dariusz Piesik Kevin J. Delaney Anna Wenda-Piesik Sebastian Sendel Piotr Tabaka Bogusław Buszewski 《Chemoecology》2013,23(4):241-250
Insect pollination and pollen feeding can reduce plant volatile emissions and future insect floral attraction, with oviposition having different effects. Meligethes aeneus F. (Coleoptera: Nitidulidae), is a pollen-feeding pest beetle of oilseed rape, Brassica napus L. (Brassicaceae). We measured plant VOC emission over 72 h from two types of 24 h M. aeneus exposure to B. napus: pollen feeding vs. flower bud injury and oviposition. The most abundant constitutive volatile organic compounds (VOCs), lilac aldehydes A (LA A) & B (LA B) and veratrole (VER), had 30–40 % reductions from M. aeneus pollen-feeding exposure at 24 h and 50–90 % reductions by 72 h, with greater reductions after bud injury and oviposition. Linalool (LIN), a common herbivore-induced plant volatile (HIPV), emission did not change at 24 h, but was induced six- to sevenfold 48 h after both exposure treatments. By 72 h, LIN had even greater (tenfold) induction after bud injury and oviposition, but no induction from pollen feeding. Three common HIPVs (β-caryophyllene, = βCAR (E)-β-farnesene = EβFAR, and (Z)-β-ocimene = ZβOCI) were progressively induced up to 2.5-fold 72 h after floral bud injury and oviposition. We assayed M. aeneus adult behavioral responses to LA A and B, and VER. Both M. aeneus sexes were attracted to higher concentrations than single plant constitutive emission for these VOCs, but avoided much higher doses. Progressive LA A and B, and VER, emission reductions might help plants (e.g., B. napus) to avoid future interactions with pollen-feeding pest herbivores (e.g., M. aeneus). After bud injury and oviposition, HIPV induction could help plants deter future oviposition and/or attract natural enemies to deposited eggs. 相似文献
998.
999.
Queen conch, Strombus gigas, is a commercially important gastropod that has been exploited throughout the Caribbean islands for thousands of years. Shell
middens in the region are the physical record of a long-term fishery and their study can provide valuable information on selectivity
patterns followed by fishermen and on resulting morphological shifts reflected by shells. In this study, we surveyed 27 middens
located at Los Roques, Venezuela, to assess pre-Columbian and modern fisheries and measure their impact on local populations
of queen conch. Pre-Columbian middens, covering a period of approximately 350 years of exploitation (1160–1540 A.D.), were
mostly composed of adult shells (89%) and mean length of catch was estimated at 22.4 ± 0.2 cm (mean ± SE). A decrease in mean
length of catch was observed throughout the modern fishery regime, estimated at 22.2 ± 0.3 cm in 1950–1971 and 20.0 ± 0.3 cm
in 1990–1995. Higher proportions of immature individuals ranging from 48 to 67% were found in modern middens. Additionally,
a decrease in mean length of mature individuals was detected throughout the modern fishery regime. The appearance of younger
and smaller specimens is considered as a sign of heavy exploitation of local populations of queen conch during modern fisheries.
Pre-Columbian middens in contrast, permitted to establish a relative baseline from which to compare values registered throughout
modern times. 相似文献
1000.
Rui Lourenço Vincenzo Penteriani Maria del Mar Delgado Michela Marchi-Bartolozzi João Eduardo Rabaça 《Behavioral ecology and sociobiology》2011,65(9):1709-1714
Intraguild predation (IGP) has been explained in terms of competitor-removal, food-stress and predator-removal hypotheses.
Only the first two hypotheses have been fairly well studied. To test the predator-removal hypothesis as a force determining
IGP in avian predators, we performed a field experiment to simulate the presence of an IG predator (eagle owl Bubo bubo dummy) in the surrounding of the nests of four potential IG prey (black kite Milvus migrans, red kite Milvus milvus, booted eagle Aquila pennata and common buzzard Buteo buteo). To discard the possibility that an aggressive reaction towards the eagle owl was not related to the presence of the IG
predator, we also presented a stuffed tawny owl Strix aluco, which is a potential competitor but cannot be considered an IG predator of the studied diurnal raptors considered in the
experiment. While almost always ignoring the tawny owl, raptors chiefly showed an interspecific aggressive behaviour towards
their IG predator. Our results seem to support the predator-removal hypothesis, as the IG prey may take advantage of the diurnal
inactivity of the IG predator to remove it from their territory. However, the recorded behaviour may be also considered as
a special variety of mobbing (i.e. a prey’s counter-strategy against its predator), where the mobber is sufficiently powerful
to escalate predator harassment into deliberate killing attempts. In their turn, eagle owls can respond with an IG predatory
behaviour aimed at removing IG prey species which are highly aggressive mobbers. 相似文献