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91.
The carbon isotope analysis [delta13C values] of organic samples can be a useful research in ecological studies because delta13C values are indicative of the plant source. This study investigated the changes in plant communities along the grassland-forest boundary in the alpine forest at Ta-Ta-Chia long term ecological research (LTER) site in central Taiwan using carbon isotope data. The aim of this study was focused on the forest fire affected the change of vegetation community. Four pedons from grassland dominated by Miscanthus transmorrisonensis (pedons 1 and 2), transition zone by Tsuga and Yushania nittakeyamensis (pedon 3), and forest zone by Tsuga and nittakeyamensis (pedon 4) were examined. Soil organic matter (SOM) delta13C values in the upper soil horizon were similar to delta13C values of the overlaying vegetation types. This indicates that the boundary between these plant communities remained the same in the past decades. The delta13C values of the grassland SOM ranged from -19.4 per thousand to -24.1 per thousand, showing decrease with soil depth. This suggests that C4 plants (transmorrisonensis) have replaced C3 plants of Tsuga and nittakeyamensis. The delta13C values of the Tsuga forest area (pedon 4) range from -27.0 per thousand to -23.5 per thousand and showed only slight change with soil depth, implying that C3 plants have remained the major species in the forest. 相似文献
92.
William R. King 《Journal of the Air & Waste Management Association (1995)》2013,63(3):275-277
There are economic and regulatory incentives for considering alternatives to the direct land disposal of solvent-bearing hazardous waste streams (EPA Hazardous Waste Codes: F001, F002, F003, F004, and F005). These alternatives include recycle/reuse (including use as a fuel substitute), destruction of a stream's solvent component, and treatment prior to land disposal. This paper reviews these three waste management alternatives and discusses their applicability to solvent waste streams having various physical characteristics. Seven waste treatment techniques which may be used to handle solvent wastes are described: incineration, agitated thin-film evaporation, fractional distillation, steam stripping, wet oxidation, carbon adsorption, and activated sludge biological treatment. 相似文献
93.
Cui Fangda Zhao Lin Daskiran Cosan King Thomas Lee Kenneth Katz Joseph Boufadel Michel C. 《Environmental Fluid Mechanics》2020,20(6):1553-1578
Environmental Fluid Mechanics - Oil dispersion under a deep-water plunging breaker of height 0.15 m was studied by coupling the Lagrangian particle tracking code (NEMO3D) with the... 相似文献
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Endeis laevis (Grube) is the more littoral of the two British members of the Endeidae (Pycnogonida). The process of vitellogenesis is examined. It closely resembles that of annelids and Limulus polyphemus, in which the majority of the yolk is synthesised within the oocyte with only a small contribution from outside the oocyte. This contrasts with the method in insects in which most of the yolk comes from outside the oocyte. The vitellogenic process is slow, the eggs accumulating yolk over the winter. Although E. laevis has two reproductive cycles each year, only one brood is produced, juveniles occurring over a restricted period (July and early August). 相似文献
97.
Yorianta?Sasaerila Regine?Gries Gerhard?Gries Grigori?Khaskin Skip?King Stephen?Takács Hardi?) 《Chemoecology》2003,13(2):89-93
Summary. During peak calling activity by male oil palm bunch
moths, Tirathaba mundella Walker (Lepidoptera: Pyralidae), their
hairpencils, wings or entire body were extracted in hexane. Gas
chromatographic-electroantennographic detection (GC-EAD) analyses of
hair pencil extracts revealed four compounds that consistently elicited
responses from female antennae. The NMR spectrum of isolated compound 1,
and mass spectra and retention indices of compounds 1–4 suggested that
they were (3S,6S)-2,2,6-trimethyl-6-vinyl-tetrahydro-pyran-3-ol (1),
4-hydroxy-3-methoxy-benzaldehyde (2, vanillin),
6,10,14-trimethyl-2-pentadecanone (3), and
6,10,14-trimethyl-2-pentadecanol (4). Comparative GC and GC-MS analyses
of hair pencils extract and synthetic standards confirmed these
structural assignments. Moreover, comparative chromatography of
synthetic and hairpencil-isolated 1 on a Cyclodex-B column (which
separated the four stereoisomers with baseline resolution) revealed that
male T. mundella produce the SS-stereoisomer (SS-1). In field cage
bioassay experiments in Palembang, Indonesia, synthetic SS-1 and
vanillin in combination, but not singly, attracted female T. mundella.
SS-1 plus vanillin were as effective as male T. mundella in attracting
females. Compounds 3 and 4 did not enhance the blend's attractiveness.
Received October 11 2002; accepted March 14, 2003.
R1D="
Correspondence to: Gerhard Gries, email: gries@sfu.ca 相似文献
98.
In mark-recapture studies, various techniques can be used to uniquely identify individual animals, such as ringing, tagging
or photo-identification using natural markings. In some long-term studies more than one type of marking procedure may be implemented
during the study period. In these circumstances, ignoring the different mark types can produce biased survival estimates since
the assumption that the different mark types are equally catchable (homogeneous capture probability across mark types) may
be incorrect. We implement an integrated approach where we simultaneously analyse data obtained using three different marking
techniques, assuming that animals can be cross-classified across the different mark types. We discriminate between competing
models using the AIC statistic. This technique also allows us to estimate both relative mark-loss probabilities and relative
recapture efficiency rates for the different marking methods. We initially perform a simulation study to explore the different
biases that can be introduced if we assume a homogeneous recapture probability over mark type, before applying the method
to a real dataset. We make use of data obtained from an intensive long-term observational study of UK female grey seals (Halichoerus grypus) at a single breeding colony, where three different methods are used to identify individuals within a single study: branding,
tagging and photo-identification based on seal coat pattern or pelage. 相似文献
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