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111.
Jürgen Wittsiepe Ulrich Ewers Petra Schrey Michael Kramer Martin Exner Fidelis Selenka Wilhelm Beine Klaus Kemper Detlef Schmeer Helmut Weber 《Environmental Sciences Europe》1993,5(4):206-215
This study was designed to assess the degree of exposure to PCDD/F in 56 selected persons living in the vicinity of a former copper smelter located in Marsberg, Germany. The copper smelter was in operation until 1945. In 1991, high levels of PCDD/F were found particularly in materials from the slag dumps (10 000 – 100 000 ng TE/kg). The levels of PCDD/F in blood fat were used as parameters for individual PCDD/F exposure. Since only limited reference data for PCDD/F in human blood were available, blood samples of a reference group were analyzed in the same way. The criteria were collected from a group matched for sex, age (±3 years) and body mass. The median NATO/CCMS-Toxicity equivalency values (NATO/CCMS-TE-values) of the Marsberg group (43,2 pg NATO/CCMS-TE/g blood fat) and the reference group (43,0 pg NATO/CCMS-TE/g blood fat) were similar, whereas the arithmetic mean of the Marsberg group (52,7 pg NATO/CCMS-TE/g blood fat) was higher than that of the reference group (44,4 pg NATO/CCMS-TE/g blood fat). The frequency distribution of the individual TE-values of the Marsberg group was slightly shifted toward higher values. The individuals of the Marsberg group had significantly higher levels of PentaCDF, HexaCDF and HeptaCDF on average than the individuals of the reference group. On the basis of TE-values, the majority of the individuals from Marsberg did not have an increased body burden of PCDD/F. However, some individuals could be identified with TE-values exceeding background levels ranging up to 231 pg NATO/CCMS-TE/g blood fat. Although it must be assumed that the unusual congener pattern found in many of the test subjects is a result of ingestion of contaminated slag material or soil, the findings of this study could not verify this fact. 相似文献
112.
In recent years thermal utilization of mixed wastes and solid recovered fuels has become of increasing importance in European waste management. Since wastes or solid recovered fuels are generally composed of fossil and biogenic materials, only part of the CO2 emissions is accounted for in greenhouse gas inventories or emission trading schemes. A promising approach for determining this fraction is the so-called radiocarbon method. It is based on different ratios of the carbon isotopes 14C and 12C in fossil and biogenic fuels. Fossil fuels have zero radiocarbon, whereas biogenic materials are enriched in 14C and reflect the 14CO2 abundance of the ambient atmosphere. Due to nuclear weapons tests in the past century, the radiocarbon content in the atmosphere has not been constant, which has resulted in a varying 14C content of biogenic matter, depending on the period of growth. In the present paper 14C contents of different biogenic waste fractions (e.g., kitchen waste, paper, wood), as well as mixtures of different wastes (household, bulky waste, and commercial waste), and solid recovered fuels are determined. The calculated 14C content of the materials investigated ranges between 98 and 135 pMC. 相似文献
113.
Comparative goal-oriented assessment of conventional and alternative sewage sludge treatment options
Phosphorous (P) is a limited and non-substitutable resource. Sewage sludge contains significant amounts of P and is therefore a widely applied fertilizer. Due to its organic and inorganic contaminants, sewage sludge is also combusted in industrial facilities as well as in waste incinerators. This study compares five common methods and one novel alternative based on a thermo-chemical process to treat and dispose of sewage sludge with regard to environmental impact, resource recovery, and materials dissipation. The comparison is based on material flow analysis, energy balances, selected LCA impact analysis, and statistical entropy analysis. This work shows that the novel technology combines both advantages of the established practices: organic and inorganic pollutants are either destroyed or removed from the P containing material, and the P returned to the soil exhibits high plant-availability. The novel method also has low emissions. The additional energy requirements should be reduced. However, with regards to sewage sludge P recovery is more important than energy recovery. 相似文献
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116.
While it is widely known that sustainable development is the only sound and viable pathway for humankind’s future, its attainment remains elusive despite intensive efforts and some successes. The current industrial society approach based on product and process innovation in a variety of fields is not providing the expected results in addressing this important issue. In an attempt to carry out this unavoidable task, Osaka University’s Research Institute for Sustainability Science (RISS) introduces an integral and dynamic innovation system where technology plays a key role in fulfilling societal functions. This innovation system adopts a highly solution-driven approach that makes use of backcasting techniques based on long-term visions and mid-term strategic goals. Since technology management is the key to propelling effective innovation towards sustainability, we propose a technology transition management through the interaction of technology push, demand pull and institutional design, along with eight transition principles. RISS will develop this innovation system based on these three components and through the design of dynamic scenarios and their roadmaps. 相似文献
117.
Simone Gingrich Karl-Heinz Erb Fridolin Krausmann Veronika Gaube Helmut Haberl 《Regional Environmental Change》2007,7(1):37-47
This article presents a comprehensive data set on Austria’s terrestrial carbon stocks from the beginnings of industrialization
in the year 1830 to the present. It is based on extensive historical and recent land use and forestry data derived from primary
sources (cadastral surveys) for the early nineteenth century, official statistics available for later parts of the nineteenth
century as well as the twentieth century, and forest inventory data covering the second half of the twentieth century. Total
carbon stocks—i.e. aboveground and belowground standing crop and soil organic carbon—are calculated for the entire period
and compared to those of potential vegetation. Results suggest that carbon stocks were roughly constant from 1830 to 1880
and have grown considerably from 1880 to 2000, implying that Austria’s vegetation has acted as a carbon sink since the late
nineteenth century. Carbon stocks increased by 20% from approximately 1.0 GtC in 1830 and 1880 to approximately 1.2 GtC in
the year 2000, a value still much lower than the amount of carbon terrestrial ecosystems are expected to contain in the absence
of land use: According to calculations presented in this article, potential vegetation would contain some 2.0 GtC or 162%
of the present terrestrial carbon stock, suggesting that the recent carbon sink results from a recovery of biota from intensive
use in the past. These findings are in line with the forest transition hypothesis which claims that forest areas are growing
in industrialized countries. Growth in forest area and rising carbon stocks per unit area of forests both contribute to the
carbon sink. We discuss the hypothesis that the carbon sink is mainly caused by the shift from area-dependent energy sources
(biomass) in agrarian societies to the largely area-independent energy system of industrial societies based above all on fossil
fuels. 相似文献
118.
119.
Kerstin?E.?ThonhauserEmail author Shirley?Raveh Attila?Hettyey Helmut?Beissmann Dustin?J.?Penn 《Behavioral ecology and sociobiology》2013,67(12):1961-1970
Females often show multi-male mating (MMM), but the adaptive functions are unclear. We tested whether female house mice (Mus musculus musculus) show MMM when they can choose their mates without male coercion. We released 32 females into separate enclosures where they could choose to mate with two neighboring males that were restricted to their own territories. We also tested whether females increase MMM when the available males appeared unable to exclude intruders from their territories. To manipulate territorial intrusion, we introduced scent-marked tiles from the neighboring males into males' territories, or we rearranged tiles within males' own territories as a control. Each female was tested in treatment and control conditions and we conducted paternity analyses on the 57 litters produced. We found that 46 % of litters were multiply sired, indicating that multiple paternity is common when females can choose their mates. Intrusion did not increase multiple paternity, though multiple paternity was significantly greater in the first trial when the males were virgins compared to the second trial. Since virgin male mice are highly infanticidal, this finding is consistent with the infanticide avoidance hypothesis. We also found that multiple paternity was higher when competing males showed small differences in their amount of scent marking, suggesting that females reduce MMM when they can detect differences in males' quality. Finally, multiple paternity was associated with increased litter size but only in the intrusion treatment, which suggests that the effect of multiple paternity on offspring number is dependent on male–male interactions. 相似文献
120.
Helmut Haenel 《Die Naturwissenschaften》1954,41(15):362-362