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141.
Diego Rubolini Maria Romano Roberta Martinelli Barbara Leoni Nicola Saino 《Behavioral ecology and sociobiology》2006,59(4):549-560
Mothers may profoundly affect offspring phenotype and performance by adjusting egg components, including steroid hormones.
We studied the effects of elevated prenatal testosterone (T) exposure in the ring-necked pheasant on the expression of a suite
of male and female traits, including perinatal response to stress, immune response, growth, and secondary sexual traits. Prenatal
T levels were increased by injecting the yolk of unincubated eggs with physiological doses of the hormone. Yolk T injection
resulted in a reduced length of male tarsal spurs, a trait which positively predicts male success in intra- and intersexual
selection and viability, whereas no direct effect on male wattle characteristics or plumage traits of either sex was observed.
Female spur length was also negatively affected by T, but to a lesser extent than in males. In addition, the covariation between
male secondary sexual traits, which are reliable quality indicators, differed between T and control males, suggesting that
the manipulation may have altered the assessment of overall male quality by other males and females. In conclusion, the negative
effects of elevated yolk T on spur length, a trait which positively predicts male fitness, coupled with the lack of effects
on growth or other traits in both sexes, provided limited evidence for mothers being subjected to a trade-off between positive
and negative consequences of yolk T deposition on offspring traits and suggest that directional selection for reduced yolk
T levels may occur in the ring-necked pheasant. 相似文献
142.
80·2 Per cent of 111 Down syndrome pregnancies had amniotic fluid (AF) alpha fetoprotein (AFP) levels on or below the median and 10·8 per cent at or below 0·5 MoM compared with 41·9 and 1·4 per cent of controls. These differences were even more striking when the gestational age was < 18 weeks compared with ⩾ 18 weeks. No such association was seen for other chromosome abnormalities including trisomy 18,45,X and mosaics, 47,XXY, 47,XXX, and other structural abnormalities and triploidy, even when high levels due to defects such as omphalocele and cystic hygroma were excluded. All cases of trisomy 13 and 80 per cent with 47,XYY had AF-AFP levels above the median. Selection of cases for karyotyping by a low level of AF-AFP would clearly fail to detect aneuploidies other than Down syndrome and is not recommended. A possible weak association between low maternal serum (MS) and AF-AFPs in Down syndrome was most evident at < 18 weeks, suggesting that MS screening between 16 and 18 weeks may be the most informative time. 相似文献
143.
Risk assessment of amniocentesis between 11 and 15 weeks: Comparison to later amniocentesis controls
We studied 693 consecutive early amniocenteses (prior to 15 weeks) and found a spontaneous abortion rate to 28 weeks' gestation of 1·5 per cent. A control group of women having standard amniocentesis (15–20 weeks) experienced a 0·6 per cent fetal loss in the same period. There were no other apparent differences between the two groups. Early amniocentesis results are generally available 4–6 weeks before standard amniocentesis and 1–3 weeks after chorionic villus sampling (CVS). Alpha-fetoprotein (AFP) can be accurately assayed in 11- to 15-week amniotic fluid samples but additional studies are necessary to determine the accuracy of neural tube defect (NTD) detection. Including the present study, over 5800 early amniocenteses have been reported and the results suggest that this is a relatively safe prenatal diagnostic test and an alternative to CVS and later amniocentesis. 相似文献
144.
145.
Barbara Neumann Michael Lütz Beatrice Schüpbach Erich Szerencsits 《Regional Environmental Change》2009,9(3):197-207
Spatial modelling of environmental indicators has been well established in landscape ecology and in nature conservation on
regional and national scales over the recent past. Yet, using spatial information as a basis for the coordination of environmental
measures on a trans-national European level reveals several shortcomings and hindrances, ranging from data quality issues
and methodological aspects to discussions on how to define ecological indicators across Europe. This paper analyzes the potential
of spatial modelling for the development and implementation of agri-environmental measures as part of rural development policies,
discussing critical aspects of spatial environmental modelling as well as chances, trends and demands. 相似文献
146.
Barbara Ruffino Silvia Fiore Maria Chiara Zanetti 《Environmental science and pollution research international》2013,20(7):4980-4992
Owing to the extensive use of artificial turfs worldwide, over the past 10 years there has been much discussion about the possible health and environmental problems originating from styrene-butadiene recycled rubber. In this paper, the authors performed a Tier 2 environmental–sanitary risk analysis on five artificial turf sports fields located in the city of Turin (Italy) with the aid of RISC4 software. Two receptors (adult player and child player) and three routes of exposure (direct contact with crumb rubber, contact with rainwater soaking the rubber mat, inhalation of dusts and gases from the artificial turf fields) were considered in the conceptual model. For all the fields and for all the routes, the cumulative carcinogenic risk proved to be lower than 10?6 and the cumulative non-carcinogenic risk lower than 1. The outdoor inhalation of dusts and gases was the main route of exposure for both carcinogenic and non-carcinogenic substances. The results given by the inhalation pathway were compared with those of a risk assessment carried out on citizens breathing gases and dusts from traffic emissions every day in Turin. For both classes of substances and for both receptors, the inhalation of atmospheric dusts and gases from vehicular traffic gave risk values of one order of magnitude higher than those due to playing soccer on an artificial field. 相似文献
147.
High-resolution satellite locations were obtained from striped marlin using Argos transmitters attached to the upper lobe
of the caudal fin. Twenty-six striped marlin were tagged off New Zealand (2005–2007) and tracked as far as the central Pacific
Ocean. Caudal fin mounted Argos tags generated 1,524 locations during a total of 659 tracking days [mean 25 (±21.24) days
per fish and 2.3 (±2.30) locations per day]. 38% of locations have an estimated accuracy of ±1 km or better. Displacement
rates from high quality locations ranged from 2.9 to 170.8 km in a 24 h period, with a mode at 20–30 km and a mean of 45 km/day.
The caudal fin attachment methodology and antenna configuration was adjusted each season to improve transmission life and
data quality, with the best results obtained in the last year of deployments (2007). The longest track duration was 102 days,
with a total displacement of 4,959 km and a total track distance from all locations received of 6,850 km. Tag shedding and
antenna failure appear to have limited the duration of tracks from SPOT tags. The high temporal and spatial resolution data
revealed behaviours not previously observed in striped marlin, including associations to subsurface bathymetric features.
High resolution location data such as these are useful inputs for statistical models used to investigate habitat selection
and switching between different behavioural modes. The geolocations calculated using ukfsst estimates from PAT tag data had
RMS errors of 1.01° latitude and 0.59° longitude when compared with SPOT tag Argos locations. 相似文献
148.
Katarzyna H. Kucharzyk Ronald L. Crawford Barbara Cosens Thomas F. Hess 《Journal of environmental management》2009,90(2):303-310
Perchlorate, an anion that originates as a contaminant in ground and surface waters, is both naturally occurring and manmade. Because of its toxicity, there has been increased interest in setting drinking water safety standards and in health effects when perchlorate is present at low (parts per billion (ppb)) levels. In January 2009, the EPA issued a heath advisory to assist state and local officials in addressing local contamination of perchlorate in drinking water. The interim health advisory level of 15 micrograms per liter (μg/L), or ppb, is based on the reference dose recommended by the National Research Council (NRC) of the National Academy of Sciences (NAS). This paper describes scope and extent of contaminant issues and a legal process of setting standards for perchlorate concentration in drinking water in the United States of America. 相似文献
149.
Barbara Fontaine Marios Drosos Pierluigi Mazzei 《Environmental science and pollution research international》2014,21(13):8016-8024
We evaluated the catalytic activity of a water-soluble iron-porphyrin in an oxidative coupling reaction to form covalent bonds between 2,4-dichlorophenol (2,4-DCP) and humic molecules. The biomimetic catalysis in the presence of H2O2 was tested in the dark and in daylight, and changes in reaction products were revealed by high-performance liquid chromatography (HPLC) and nuclear magnetic resonance (NMR) spectroscopy. In all conditions, iron-porphyrin was effective in promoting complete disappearance of 2,4-DCP, although catalyst activity was enhanced in daylight (with a maximum turnover number of 85.13). Further evidence of the occurred covalent coupling between 2,4-DCP and humic molecules was revealed by diffusion-ordered nuclear magnetic resonance (DOSY-NMR) spectroscopy that showed a reduced diffusivity of 2,4-DCP after the catalytic reaction. These findings indicate that iron-porphyrin is an efficient catalyst for the covalent binding of polyhalogenated phenols to humic molecules, thereby suggesting that the copolymerization reactions may become a useful technology to remediate soils and waters contaminated by halogenated phenols and their analogues. 相似文献
150.