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Abstract. The major changes within the concepts of marine ecology are investigated, with the aim to design this new journal's scientific format. Four phases of marine sciences are distinguished: the phase of seafarers, of oceanographic expeditions, of marine stations, and of field research. The changes in the latter two are discussed in detail. The changes are described as occurring along three axes. First, as a movement towards the object; accomplished by fieldwork, scientific diving, remote controlled equipment, and by underwater experimentation. Second, the cooperation between several disciplines that led towards bridging gaps. And lastly, how the discovery of unifying principles in ecology (the development of an ecological theory) led the approach in marine ecology towards increasing complexity. 相似文献
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C. von Zanthier H. Bräuninger K. Dennerl R. Hartmann G. Hartner H. Hippmann A. Kaltenberger E. Kastelic W. Kink N. Krause N. Meidinger G. Metzner E. Pfeffermann M. Popp C. Reppin J. Riedl D. Stötter L. Strüder J. Trümper W. Weber D. Carathanassis S. Engelhard Th. Gebhart D. Hauff G. Lutz R. H. Richter H. Seitz P. Solc E. Biehler H. Böttcher E. Kendziorra J. Krämer B. Pflüger R. Staubert P. Holl J. Kemmer P. Lechner B. Maier H. Soltau R. Stötter E. Bihler 《Experimental Astronomy》1998,8(1):89-96
This paper describes the performance of the Fully Depleted pn-junction CCD (pn-CCD) system, developed for ESA's XMM-satellite mission for soft x-ray imaging and spectroscopy in the single photon counting mode in the 100 eV to 10 keV photon range. The 58 mm x 60 mm large pn-CCD array, designed and fabricated at the Semiconductor Lab (Halbleiterlabor) of the Max-Planck-Institut, uses pn-junctions for registers and as backside structure. This concept naturally enables full depletion of the detector volume independent of the silicon wafer's resistivity and thickness, and as such make it an efficient detector for the x-ray region and the infrared. For high detection efficiency in the soft x-ray region and UV, an ultrathin pn-CCD backside deadlayer has been realized. Each pn-CCD-channel is equipped with its own on-chip JFET amplifier which, in combination with the CAMEX-amplifier and multiplexing chip, facilitates parallel readout and fast data rate: the cooled pn-CCD system can be read out at a data rate up to 3 MHz with an electronic noise floor of ENC < 5 e-. 相似文献
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Proposal for applying a component-based mixture approach for ecotoxicological assessment of fracturing fluids 总被引：2，自引：2，他引：0
Janet Riedl Stefanie Rotter Sonja Faetsch Mechthild Schmitt-Jansen Rolf Altenburger 《Environmental Earth Sciences》2013,70(8):3907-3920
Hydraulic fracturing is increasingly being used to produce gas from unconventional resource sites for energy supply. Therefore, concerns about risks of this technology related to human health and the environment have to be addressed. Among the major issues is the potential contamination of surrounding water systems by chemical additives used in fracturing fluids. In this study, the ecotoxicological hazards of fracturing fluids, both, their individual components (chemicals) as well as their mixtures (product) were assessed using a component-based mixture approach. For five exemplary fracturing fluids, 40–90 wt% of the contained substances could unambiguously be defined in their chemical identity. The concentrations used in the applied fluid mixture were considered as (maximum) exposure concentrations. For components with mass fractions between 10 and 74 wt%, the effect concentrations for acute and chronic toxicity of fish, daphnia and algae were retrieved from experimental databases and through predictive modeling. The hazard indices calculated from the ratio of exposure to effect concentration were >1 for all fracturing fluids, using different scenarios. This indicated a hazard from the undiluted fracturing fluids. The assessment framework presented in this study allows for dealing with data gaps and uncertainties in a tiered fashion and in particular accommodates for combined effects resulting from chemical mixtures. It might be employed for ecotoxicological risk assessment of products containing chemical mixtures and optimization of their environmental performance. 相似文献
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The Attic–Cycladic complex of Greece comprises an Eocene high-P unit with blueschist occurrences. Unroofing of this unit took place in Oligocene–Miocene times and was accompanied by a regional low-P medium-T overprint and Miocene granitic plutonism.Apatite fission-track ages of 14 “crystalline” samples from the islands of Tinos, Mikonos and Serifos range between 13.1 and 5.3 Ma, corresponding to the middle and late Miocene. The frequency distributions of confined track lengths are characterised by high arithmetic means of 14.2–15.1 μm and by standard deviations from 0.9 to 1.6 μm. Thermochronological modelling of the data indicates rapid cooling between 10 and 6 Ma and subsequent deceleration of the cooling rates. For a short time, the Miocene plutons of Tinos, Mikonos and Serifos experienced maximum cooling rates above 50 °C/Ma.These exceptionally high cooling rates cannot be explained by strong vertical uplift and fast regional erosion. Such a process is disproved by preserved remnants of a former peneplain, including inselbergs and kaolinized tropical subsoil. On Mikonos, fast post-plutonic cooling of the lower plate was apparently accompanied by simultaneous sedimentation on the upper plate. We propose a post-plutonic cooling model which assumes strong periplutonic heat flow into much cooler host rocks and fast extensional unroofing. 相似文献
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