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991.
Stefan Gold 《Mitigation and Adaptation Strategies for Global Change》2011,16(4):439-462
What are the management challenges and opportunities of bio-energy chains for both running their business efficiently and effectively and fostering the relationships with most relevant external stakeholders? This question is approached by systematically reviewing papers at the interface of bio-energy and supply chain or logistics issues. The review conducted as content analysis is based on an analytic framework that conceives bio-energy chains between challenges and benefits of bio-energy production with simultaneous internal supply chain management and external stakeholder management needs. Smartly designed and operated bio-energy projects hold promising potentials of contributing to sustainable development by both mitigating climate change and strengthening adaptation capabilities. Our analysis distils specific strategies and success factors for tapping this potential on two levels: On a supply chain level, individually adapted and designed supply chain systems relying on trustful information exchange, cooperation and relational governance safeguard profitability while holding adverse ecological and social impacts of operation down; they allow, for instance, minimising costs and emissions, implementing new technologies, and coping with environmental uncertainties such as crop failures and volatile prices. On a stakeholder level, governments as key actors for designing the future legal framework of bio-energy are primary targets for lobbying activities of bio-energy representatives. Respective arguments may focus on economic development and job generation. By minimising its adverse impacts on society and eco-systems and by communicating these efforts credibly, bio-energy warrants its superiority over fossil energy systems. Involving NGOs and residents in early stages of bio-energy projects via transparent two-way communication considerably increase societal acceptance. 相似文献
992.
Supply chain and logistics issues of bio-energy production 总被引:1,自引:0,他引:1
Stefan Gold 《Journal of Cleaner Production》2011,19(1):32-42
993.
Advancing sustainable urban transformation 总被引:1,自引:0,他引:1
994.
The stridulation of the giant pill-millipede genus Sphaerotherium from South Africa, one of only three groups of millipedes that produce sounds, was studied. One hundred one stridulation
series of a total of nine different species (Sphaerotherium dorsaloide, Sphaerotherium hanstroemi, Sphaerotherium mahaium, Sphaerotherium similare, Sphaerotherium punctulatum, Sphaerotherium convexitarsum, Sphaerotherium dorsale, Sphaerotherium rotundatum, and Sphaerotherium perbrincki) were analyzed. Stridulation sounds are produced only with a special field of ribs on the posterior surface of the posterior
telopod, which is actively moved over a field of sclerotized nubs on the inner margin of the anal shield. The Sphaerotherium male usually stridulates only when in contact with a female to initiate mating. This seems to prevent the female from volvating
into a ball or stimulate the female to uncoil when already rolled in. The sound analyzes revealed a broad frequency spectrum
in all stridulation sounds produced, without obvious differences in frequency distribution among species. However, the temporal
pattern of the stridulation varies greatly between species and seems to be species-specific, arguing for a species recognition
function of the stridulation during courtship behavior. A single species (S. punctulatum) was found to stridulate during mating while three species also show postcopulatory stridulation. Apparently, pill-millipedes
are not capable of acoustic perception, as no hearing organs are known, indicating that the communication is mainly based
on perception of temporal vibration patterns, and not of the acoustic signal itself. The need to overcome the rolling-in reflex
of the female is developed as a hypothesis why stridulation exists only in millipedes able to coil into a ball, and apparently
evolved four times independently in the superorder Oniscomorpha. 相似文献
995.
This study combines biology and mathematics, showing that a relatively simple question from molecular biology can lead to
complicated mathematics. The question is how to calculate the number of theoretically possible aliphatic amino acids as a
function of the number of carbon atoms in the side chain. The presented calculation is based on earlier results from theoretical
chemistry concerning alkyl compounds. Mathematical properties of this number series are highlighted. We discuss which of the
theoretically possible structures really occur in living organisms, such as leucine and isoleucine with a chain length of
four. This is done both for a strict definition of aliphatic amino acids only involving carbon and hydrogen atoms in their
side chain and for a less strict definition allowing sulphur, nitrogen and oxygen atoms. While the main focus is on proteinogenic
amino acids, we also give several examples of non-proteinogenic aliphatic amino acids, playing a role, for instance, in signalling.
The results are in agreement with a general phenomenon found in biology: Usually, only a small number of molecules are chosen
as building blocks to assemble an inconceivable number of different macromolecules as proteins. Thus, natural biological complexity
arises from the multifarious combination of building blocks. 相似文献
996.
Analytical methods for the determination of brominated flame retardants (BFRs), with a special emphasis on polybrominated diphenyl ethers (PBDEs) are reviewed. A number of procedures, which can be applied to the analysis of PBDEs and polybrominated biphenyls (PBBs), and in some cases for hexabromocyclododecane (HBCD), in environmental and human samples are described. Because several BFRs, such as tetrabromobisphenol-A (TBBP-A), BDE 209 and, to some extent, HBCD, may require a different approach, specific advice on their analysis is given separately when needed. Sample pretreatment, extraction, cleanup and fractionation, injection techniques, chromatographic separation, detection methods, quality control and method validation are discussed. For each topic, an overview is given of the current status of the field and recommendations for an appropriate analytical approach are presented. 相似文献
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