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151.
Phillip Williamson Douglas W.R. Wallace Cliff S. Law Philip W. Boyd Yves Collos Peter Croot Ken Denman Ulf Riebesell Shigenobu Takeda Chris Vivian 《Process Safety and Environmental Protection》2012,90(6):475-488
Dangerous climate change is best avoided by drastically and rapidly reducing greenhouse gas emissions. Nevertheless, geoengineering options are receiving attention on the basis that additional approaches may also be necessary. Here we review the state of knowledge on large-scale ocean fertilization by adding iron or other nutrients, either from external sources or via enhanced ocean mixing. On the basis of small-scale field experiments carried out to date and associated modelling, the maximum benefits of ocean fertilization as a negative emissions technique are likely to be modest in relation to anthropogenic climate forcing. Furthermore, it would be extremely challenging to quantify with acceptable accuracy the carbon removed from circulation on a long term basis, and to adequately monitor unintended impacts over large space and time-scales. These and other technical issues are particularly problematic for the region with greatest theoretical potential for the application of ocean fertilization, the Southern Ocean. Arrangements for the international governance of further field-based research on ocean fertilization are currently being developed, primarily under the London Convention/London Protocol. 相似文献
152.
Keiichi Honda Hiroshi Minematsu Ken’ichiro Muta Hisashi ?mura Wataru Nishii 《Chemoecology》2012,22(1):55-63
The sulfur butterfly, Colias erate, utilizes various legumes as host plants. We examined the chemical constituents of its primary host plant, Trifolium repens (white clover), to identify phytochemicals inducing oviposition by C. erate females. Since one of the four aqueous subfractions prepared from a methanolic extract of the plant has previously been shown
to be the most responsible for the oviposition-stimulatory activity exerted by the plant, chemical analyses were conducted
of the fraction concerned. Activity-directed fractionation of the subfraction by ion-exchange chromatography revealed that
the key substance(s) resided in the neutral fraction. Preparative TLC of the neutral fraction and subsequent spectral analyses
identified d-(+)-pinitol, glycerin, methyl β-d-glucoside, and myo-inositol as characteristic components together with ubiquitous sugars (e.g., sucrose and glucose). Of these, only pinitol
singly evoked significant oviposition responses at concentrations over 0.05%. In dual-choice bioassays, however, females laid
significantly more eggs on pinitol solutions admixed with glycerin or methyl β-d-glucoside than on pinitol alone. Two cyanoglucosides, linamarin, and lotaustralin, occurring in the other aqueous subfractions,
also synergistically increased the oviposition response in combination with pinitol. The results clearly indicated that pinitol
is a crucial oviposition stimulant involved in host recognition, while glycerin, methyl β-d-glucoside, linamarin, and lotaustralin function as synergists. We further examined the oviposition responses of C. erate females to aqueous fractions, along with their chemical compositions, that had been prepared from five other host plants
and a non-host plant, Aristolochia debilis (Aristolochiaceae), on which oviposition occasionally took place in an outdoor cage during the experiments.
The plant species accepted by ovipositing females were all found to contain pinitol in amounts enough to induce egg laying
by the butterfly, thus leading to the conclusion that pinitol serves as the essential mediator in recognizing and accepting
potential host plants. 相似文献
153.
Ken Tan Tanya Latty Zongwenu Hu Zhengwei Wang Shuang Yang Weiweng Chen Benjamin P. Oldroyd 《Behavioral ecology and sociobiology》2014,68(1):13-20
Honey bee foragers need to asses and make trade-offs between a number of potentially conflicting floral attributes. Here, we investigate multi-attribute decision making in the eastern honey bee, Apis cerana, when foraging on food sources that varied in warmth and sucrose concentration. We show that foragers prefer warm (30 °C) sucrose solution over cool (10 °C) sucrose solution and concentrated (30 % w/w) sucrose solution over dilute (15 % w/w) sucrose solution. When we offered the preferred sucrose concentration (30 % w/w) at the less-preferred temperature (10 °C), and the less-preferred sucrose concentration (15 % w/w) at the preferred temperature (30 °C), foragers prioritized warmth by choosing the warmer, but lower concentration solution. When the temperature difference was less extreme, bees preferred more concentrated cooler syrup (30 % ww at 15 °C over 15 % 30 °C). However, the addition of a decoy item to the choice set had a significant effect on the bees' preferences. Our results highlight the critical importance of considering context effects when measuring the foraging preferences of animals. 相似文献
154.
155.
Murayama H Moriyama N Mitobe H Mukai H Takase Y Shimizu Ki Kitayama Y 《Chemosphere》2003,52(5):825-833
A simple method for quantitative analyses of organic chlorine pesticides (OCPs) in environmental water samples such as rainwater, river water and seawater using activated carbon fiber filters (ACFF) is described. ACFF was used as adsorbent to collect the chemicals in water samples. The collection of OCPs was completed almost for one day by stirring the mixture of the sample and the ACFF chips at room temperature. The adsorbed OCPs on the ACFF could be extracted easily with toluene-ethanol (4:1) mixed solvent. The purified extract by a florisil column chromatograph was followed by the analysis using high-resolution gas chromatograph/high-resolution mass spectrometer. Recoveries of OCPs spiked to actual samples such as rainwater, river water and seawater samples were approximately more than 80%, and the coefficients of variations were within 10%. This method was applied to the actual samples and was confirmed to be applicable for monitoring sub-ng/l level OCPs in environmental water samples. 相似文献
156.
Elwood L. Shafer Robert Carline Richard W. Guldin H. Ken Cordell 《Environmental management》1993,17(5):669-682
The travel clost method (TCM) and contingent valuation method (CVM) were used to evaluate the economic value of six different
ecotourism activities involving observation of wildlife in Pennsylvania. The six activities were: catch-and-release trout
fishing; catch-and-release trout fishing with fly-fishing equipment; viewing waterfowl; watching elk; observing migration
flights of raptors; and seeing live wildlife in an environmental education setting. TCM results provided significant statistical
relationships between level of use and travel costs for the two types of trout fishing activities. CVM provided estimates
of consumer surplus for the other four sites. The consumers' surplus value (1988 dollars) of all six activities to participants
amounted to a total of more than $1.28 million annually—twice the total out-of-pocket expenditures of approximately $640,000
spent to visit the sites. The economic amenity values of the six activities compare favorably with similarly derived values
in other studies for hunting, fishing, hiking, and backpacking in dispersed recreation environments and wilderness areas in
western states. 相似文献
157.
The diversion of biodegradable waste from landfill is of key importance in developing a sustainable waste strategy for the next decade and beyond. The proliferation of waste treatment technologies such as Mechanical Biological Treatment, Anaerobic Digestion and Composting will be paramount in achieving this strategic goal. This paper evaluates the scientific information needed to undertake an effective assessment of the potential public health risks from exposure to bioaerosols in the vicinity of commercial composting activities. Knowledge gaps currently exist in the scientific and regulatory community that limit our ability to effectively characterise source-term emissions, develop reliable dose–response data and accurately model the dispersion of bioaerosols. Consequently reliable risk estimates cannot be developed to inform the management of these potential risks. This uncertainty may prove a barrier to progress in achieving waste diversion and composting targets in Wales and the rest of the UK. A robust and extensive evidence base is required to inform the risk assessment process. This paper advocates the need for further, more focussed research into hazard characterisation of viable and non-viable organisms, improved dose–response data, exposure assessment techniques and an evaluation of the existing risk control and mitigation measures currently adopted. It is hoped that his will enable effective, timely and proportional risk management and mitigation measures to be developed that will foster the confidence required in composting technologies to achieve waste diversion targets and develop sustainable waste strategies. 相似文献
158.
159.
The fossil record of late Campanian tyrannosauroids of western North America has a geographic gap between the Northern Rocky
Mountain Region (Montana, Alberta) and the Southwest (New Mexico, Utah). Until recently, diagnostic tyrannosauroids from the
Southwest were unknown until the discovery of Bistahieversor sealeyi from the late Campanian of New Mexico. Here we describe an incomplete skull and postcranial skeleton of an unusual tyrannosaurid
from the Kaiparowits Formation (Late Cretaceous) of Utah that represents a new genus and species, Teratophoneus curriei. Teratophoneus differs from other tyrannosauroids in having a short skull, as indicated by a short and steep maxilla, abrupt angle in the
postorbital process of the jugal, laterally oriented paroccipital processes, short basicranium, and reduced number of teeth.
Teratophoneus is the sister taxon of the Daspletosaurus + Tyrannosaurus clade and it is the most basal North American tyrannosaurine. The presence of Teratophoneus suggests that dinosaur faunas were regionally endemic in the west during the upper Campanian. The divergence in skull form
seen in tyrannosaurines indicates that the skull in this clade had a wide range of adaptive morphotypes. 相似文献
160.
Kraaijeveld K Reumer BM Mouton L Kremer N Vavre F van Alphen JJ 《Die Naturwissenschaften》2011,98(3):175-180
Wolbachia is a maternally inherited bacterium that manipulates the reproduction of its host. Recent studies have shown that male-killing
strains can induce cytoplasmic incompatibility (CI) when introgressed into a resistant host. Phylogenetic studies suggest
that transitions between CI and other Wolbachia phenotypes have also occurred frequently, raising the possibility that latent CI may be widespread among Wolbachia. Here, we investigate whether a parthenogenesis-inducing Wolbachia strain can also induce CI. Parthenogenetic females of the parasitoid wasp Asobara japonica regularly produce a small number of males that may be either infected or not. Uninfected males were further obtained through
removal of the Wolbachia using antibiotics and from a naturally uninfected strain. Uninfected females that had mated with infected males produced
a slightly, but significantly more male-biased sex ratio than uninfected females that had mated with uninfected males. This
effect was strongest in females that mated with males that had a relatively high Wolbachia titer. Quantitative PCR indicated that infected males did not show higher ratios of nuclear versus mitochondrial DNA content.
Wolbachia therefore does not cause diploidization of cells in infected males. While these results are consistent with CI, other alternatives
such as production of abnormal sperm by infected males cannot be completely ruled out. Overall, the effect was very small
(9%), suggesting that if CI is involved it may have degenerated through the accumulation of mutations. 相似文献