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901.
Assessment of an index of biological integrity (IBI) to quantify the quality of two tributaries of river Chenab,Sialkot, Pakistan 总被引:3,自引:0,他引:3
Nullah Aik and Nullah Palkhu, two tributaries of river Chenab, were investigated for the assessment of fish habitat degradation
as indicator of stream health. Fish abundance data were collected from 18 sites from September 2004 to April 2006 to develop
multimetric indices for fish assemblage integrity and to detect the intensity of habitat degradation. A total of 12 metrics
were calculated on the basis of taxonomic richness, habitat preference, trophic guild, stress tolerance and origin of species
to develop stepped and continuous index of biological integrity (IBI) criteria. Cluster analysis (CA) classified sites based
on species composition into three groups, viz., reference, moderately impaired and impaired groups. Non-metric multidimensional
scaling (NMDS) was applied to identify underlying ecological gradient to highlight the habitat degradation. NMDS segregated
two sites as less impaired, five sites as moderately impaired and eleven sites as impaired groups. Axes 1 and 2 explained
a total variation of 53.3%. First axis explained the level of habitat impairment, whereas axis 2 indicated species richness
along longitudinal gradient of streams. Sites located upstream of Nullah Aik showed higher IBI scores which dropped to its
lowest in downstream sites near Sialkot city. Lowest values of IBI of sites in close proximity of city indicated the role
of anthropogenic activities in catchment areas. The results indicated that variability in water chemistry can be related as
a function of stream sites impairments (i.e., unimpaired, moderately impaired, and severely impaired). Water quality parameters
showed strong correlation with IBI scores. Significantly negative correlation of IBI scores with COD, TDS, turbidity, Fe,
Cr, Zn and positive correlation with DO and pH was found. The results can be used for restoration and future management of
small streams passing through urban areas of Pakistan.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Handling editor: J. A. Cambray 相似文献
902.
C. Pinto-Cruz J. A. Molina M. Barbour V. Silva M. D. Espírito-Santo 《Hydrobiologia》2009,634(1):11-24
Temporary ponds are seasonal wetlands annually subjected to extreme and unstable ecological conditions, neither truly aquatic
nor truly terrestrial. This habitat and its flora have been poorly studied and documented because of the ephemeral character
of the flora, the changeable annual weather that has a great effect on the small, herbaceous taxa and the declining abundance
of temporary ponds. The objectives of this study are: (a) to define plant community diversity in terms of floristic composition
of ephemeral wetlands in SW Portugal, (b) to identify temporary pond types according to their vegetation composition and (c)
to identify those ponds that configure the European community priority habitat (3170* – Mediterranean temporary ponds).
Vegetation sampling was conducted in 29 ponds, identifying 168 species grouped among 15 plant communities. Soil texture, pH,
organic C and N content were measured, but only N and percent of clay appear to be related with the distribution of each community
type. The results showed that ephemeral wetlands could be classified into four type: vernal pools, marshlands, deep ponds
and disturbed wetlands. Vernal pools correspond to the Mediterranean temporary ponds (3170*), protected as priority habitat
under the EU Habitats Directive. Submersed Isoetes species (Isoetes setaceum and Isoetes velatum) represents, together with Eryngium corniculatum, the indicator species for vernal pools. We identify also indicator plant communities of this priority habitat, namely I. setaceum and E. corniculatum–Baldellia ranunculoides plant communities. In this region, the conservation of temporary ponds has so far been compatible with traditional agricultural
activities, but today these ponds are endangered by the intensification of agriculture and the loss of traditional land use
practices and by the development of tourism.
Guest editors: B. Oertli, R. Cereghino, A. Hull & R. Miracle
Pond Conservation: From Science to Practice. 3rd Conference of the European Pond Conservation Network, Valencia, Spain, 14–16
May 2008 相似文献
903.
S. Matthew Drenner Stanley I. Dodson Ray W. Drenner John E. Pinder III 《Hydrobiologia》2009,632(1):225-233
Lentic community structure varies across a size gradient of ponds and lakes with physical factors, such as pond drying, and
biotic factors, such as fish predation, determining the species assemblage. We studied the effects of pond drying and fish
absence on crustacean zooplankton across a gradient of pond sizes in a Texas grassland. We determined the species compositions
and size distributions of crustacean zooplankton in 20 temporary and 18 permanent ponds in April after March rains had refilled
the ponds. The surface areas of temporary and permanent ponds ranged from <0.01 to 0.21 ha and 0.04 to 13.8 ha, respectively,
and temporary ponds were significantly smaller, on average, than permanent ponds. Fish were absent from all temporary ponds
and present in all permanent ponds. We detected a difference in the zooplankton species assemblages of the temporary and permanent
ponds. Out of 14 total zooplankton taxa that occurred in eight or more ponds, seven taxa were significantly more prevalent
in temporary ponds and four taxa were significantly more prevalent in permanent ponds. The sizes of zooplankton in the temporary
fishless ponds were greater than those in the permanent ponds with fish present. We concluded that pond size mediated susceptibility
to pond drying, and pond drying determined the presence and absence of fish and their secondary trophic-level effect on zooplankton
community structure.
Handling editor: Steven Declerck 相似文献
904.
Aims: 3-Methylindole (3-MI) is a degradation product of l -tryptophan and is both an animal waste malodorant and threat to ruminant health. Culture conditions influencing 3-MI production in Clostridium scatologenes ATCC 25775 were investigated.
Methods and Results: Extracellular 3-MI levels in cells cultured in brain heart infusion (BHI) medium (pH 7·0) at 33°C and 37°C for 72 h were 907 ± 38 and 834 ± 121 μ mol l−1 , respectively. Cells cultured in tryptone-yeast (TY) extract medium at 37°C for 48 h produced 104 ± 86 μ mol l−1 3-MI; however, addition of 1 mmol l−1 l -tryptophan failed to increase extracellular levels (113 ± 50 μ mol l−1 3-MI). Specific activity of indole acetic acid decarboxylase measured in BHI, TY and TY plus 1 mmol l−1 tryptophan-grown cells displayed 35-, 33- and 76-fold higher levels than in semi-defined medium-grown cells.
Conclusions: When cultured in rich medium, at 33°C or 37°C and pH 7·0, Cl. scatologenes ATCC 25775 optimally produced 3-MI. Addition of l- tryptophan to medium did not lead to significant increases in extracellular 3-MI levels. Whole cell assays indicate growth in rich medium significantly up-regulated 3-MI production.
Significance and Impact of the Study: Information presented here may prove useful in understanding what factors influence 3-MI production in malodorous animal wastes. 相似文献
Methods and Results: Extracellular 3-MI levels in cells cultured in brain heart infusion (BHI) medium (pH 7·0) at 33°C and 37°C for 72 h were 907 ± 38 and 834 ± 121 μ mol l
Conclusions: When cultured in rich medium, at 33°C or 37°C and pH 7·0, Cl. scatologenes ATCC 25775 optimally produced 3-MI. Addition of l- tryptophan to medium did not lead to significant increases in extracellular 3-MI levels. Whole cell assays indicate growth in rich medium significantly up-regulated 3-MI production.
Significance and Impact of the Study: Information presented here may prove useful in understanding what factors influence 3-MI production in malodorous animal wastes. 相似文献
905.
The concentrations of As, Be, Cd, Cr, Hg, Mn, Ni, Pb, Sn, Tl, and V were determined in hair of 96 school children and in blood
of 144 adults living in the vicinity of a hazardous waste incinerator (HWI) (Constantí, Tarragona County, Catalonia, NE Spain).
The results were compared with those obtained in previous (1998 and 2002) surveys performed in the same area. Data were analyzed
in terms of age, sex, and specific place of residence. Current mean concentrations in hair ranged between not detected (ND)
(As, Be, and Tl) and 1.31 μg/g for Cr. In blood, Be, Hg, Mn, Sn, and Tl levels were under the respective detection limits.
The mean blood concentrations of the remaining elements ranged from 0.34 μg/dL for Cd, to 2.40 μg/dL for Pb. Significant differences
in hair and blood in relation to gender were only noted for Pb in blood. In general terms, metal concentrations in hair and
blood from subjects living in Tarragona County are lower than most levels reported for other countries in recent years. 相似文献
906.
β-Turmerin from turmeric (Curcuma longa) waste grits obtained after extraction of curcumin was purified by successive gel permeation chromatography. Homogeneity of β-turmerin was confirmed by its movement as single band both in SDS-PAGE and as well as in native (basic) PAGE. The apparent molecular mass is 34 kDa by SDS-PAGE. It is more hydrophobic protein and showed sharp single peak in RP-HPLC with retention time of 62.17 min. It is a glycoprotein as it shows the presence of amino sugars up to 0.021 gm%. In three different model systems i.e., linolenic acid micelles, erythrocyte membrane systems and liposomes, β-turmerin at 0.125 μM offered 70%, 64%, and 60% inhibition of lipid peroxidation, which is 3200 times more efficient than the standard antioxidants BHA (400 μM) and α-tocopherol (400 μM). β-turmerin inhibited diene–triene and tetraene conjugation up to 54%, 72% and 47%, respectively. β-turmerin also effectively scavenges hydroxyl radicals when compared to BHA and α-tocopherol. β-turmerin (2.5 μM) further inhibited the activation of PMNL mediated by fMLP up to the extent of 75%, where as standards BHA (400 μM) and mannitol (10 μM) inhibited the same to 65% and 55%, respectively. At 0.125 μM dose β-turmerin prevented t-BOOH induced cell death at all time intervals. In addition to the above properties, it is non-toxic to lymphocytes as it did not affect the viability of cells. The mechanism of antioxidant action of β-turmerin could probably be by counteracting/quenching of reactive oxygen species (ROS). We report the purification and characterization of β-turmerin (34 kDa), a potent antioxidant protein from turmeric waste grits. 相似文献
907.
Tea waste (TW) was investigated as a new supplement for substrate mixtures in Ganoderma lucidum cultivation. The effects of sawdust (S) based substrates supplemented with TW at the various levels (75S:25TW, 80S:20TW,
85S:15TW, and 90S:10TW) and Ganoderma lucidum strains on yield, biological efficiency (BE) and the chemical composition of fruiting bodies were determined in solid-state
fermentation. Significant differences were found among substrates regarding yield and BE, while yield and BE of the strains
were not different. The substrate formulations producing highest yield and BE were 80S:20TW (87.98 g/kg substrate and 34.90%)
and 75S:25TW (82.30 g/kg substrate and 31%). Yield and BE of substrates containing TW were generally higher than that of the
control (80sawdust:18wheat bran:1sucrose:1 CaCO3). Nitrogen, potassium, iron, and manganese contents and C:N ratios of substrates were strongly correlated with yield. BE
showed positive and significant correlations with potassium, iron and manganese. Moisture content, potassium, magnesium, calcium,
iron, and zinc contents of the fruiting bodies were affected by both strain and substrate. It was concluded that TW can be
used as a supplement for substrate preparation in G. lucidum cultivation. 相似文献
908.
Municipal solid waste is a significant contributor to greenhouse gas emissions through decomposition and life-cycle activities processes. The majority of these emissions are a result of landfilling, which remains the primary waste disposal strategy internationally. As a result, countries have been incorporating alternative forms of waste management strategies such as energy recovery from landfill gas capture, aerobic landfilling (aerox landfills), pre-composting of waste prior to landfilling, landfill capping and composting of the organic fraction of municipal solid waste. As the changing global climate has been one of the major environmental challenges facing the world today, there is an increasing need to understand the impact of waste management on greenhouse gas emissions. This review paper serves to provide an overview on the impact of landfilling (and its various alternatives) and composting on greenhouse gas emissions taking into account streamlined life cycle activities and the decomposition process. The review suggests greenhouse gas emissions from waste decomposition are considerably higher for landfills than composting. However, mixed results were found for greenhouse gas emissions for landfill and composting operational activities. Nonetheless, in general, net greenhouse gas emissions for landfills tend to be higher than that for composting facilities. 相似文献
909.
Nana O.K. Mainoo Suzelle Barrington Joann K. Whalen Luis Sampedro 《Bioresource technology》2009,100(23):5872-5875
Pineapple wastes, an abundant organic waste in Accra, Ghana, were vermicomposted using native earthworms (Eudrilus eugeniae Kinberg) collected from the banks of streams and around bath houses of this city. Triplicate pilot-scale vermidigesters containing about 90 earthworms and three other control boxes with no earthworms were fed pineapple pulp or peels, and the loss of wet mass was monitored over 20 weeks. In a second experiment, a 1:1 mixture of pineapple peels and pulp (w/w) was fed to triplicate pilot-scale vermicomposters and control boxes during a 20 week period. One month after feeding ended, the vermicompost and composted (control) waste was air dried and analyzed. During the first experiment, the vermicomposted pineapple pulp and peels lost 99% and 87% of their wet mass, respectively, indicating the potential for vermicomposting. Fresh pineapple waste exhibited an initial pH of 4.4, but after 24 weeks, the vermicompost and compost had acquired a neutral to alkaline pH of 7.2–9.2. The vermicompost contained as much as 0.4% total N, 0.4% total P and 0.9% total K, and had a C:N ratio of 9–10. A reduction of 31–70% in the Escherichia coli plus Salmonella loads and 78–88% in the Aspergillus load was observed during vermicomposting. The rapid breakdown of pineapple wastes by E. eugeniae demonstrated the viability of vermicomposting as a simple and low cost technology recycling this waste into a soil amendment that could be used by the 2500 vegetable producers of Accra and its surrounding areas. 相似文献
910.
Ariel Shabtay Yitzhak Hadar Harel Eitam Arieh Brosh Alla Orlov Yaakov Tadmor Ido Izhaki Zohar Kerem 《Bioresource technology》2009,100(24):6457-6464
The aims of the current study were to follow: (1) the capability of the edible mushroom Pleurotus ostreatus to degrade cell wall components and soluble phenols of the olive mill solid waste (OMSW), and improve it for ruminant nutrition (2) the fate of oil and the lipid-soluble compounds tocopherols, squalene and β-sitosterol in the fermented OMSW. A significant decrease in oil and lipid-soluble compounds with a concomitant shift in the fatty acid profile and degradation of soluble phenols took place already after 14 d. The utilization of lipids by the fungus shifted the degradation of the structural carbohydrates to a later stage, and significantly reduced the metabolizable energy of the OMSW. We propose that edible fungi with reduced lipase activity would preserve the energy and health promoting ingredients of the oil, and force the fungus to degrade structural carbohydrates, thus improving its digestibility. 相似文献