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81.
82.
Long-living wood products contribute to the mitigation of climate change in many ways. They act as a carbon pool during their service life, as they withdraw CO2 from its natural cycle. After their service life, they can stitute for fossil fuels if they are incinerated in adequate furnaces. Furthermore, wood products can stitute for more energy-intense products made of ‘conventional’ materials. This paper quantifies the stitution and pool effects of an increased use of wood in the building sector in Switzerland for the years 2000–2130. Life cycle data on greenhouse gas (GHG) emissions of 12 wood products and their stitutes are used as proxies for relevant building products; this data is linked to the forecasted wood flows for each group of building products in a cohort-model. For the political assessment, GHG effects occurring abroad and in Switzerland are distinguished. The results show that the pool effect of an increased use of long-living wood products is of minor importance, whereas the energetic and material stitution effects are much more relevant, especially on a long-term. For construction products, the Swiss share of the GHG effect related to the material stitution is relatively high, as mainly nationally produced materials are stituted for. For interior products, the Swiss share of the GHG effect related to the material stitution is rather small because mainly imports are stituted for. The results must be considered as rough estimates. Nonetheless, these calculations show that an increased use of wood in the building sector is a valid and valuable option for the mitigation of greenhouse gas emissions and for reaching GHG emission targets in a mid- to long-term. Still, the pool and stitution capacity of an increased use of wood is relatively small compared to the overall GHG emissions of Switzerland. 相似文献
83.
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
84.
85.
The orthogneisses of the Spessart crystalline complex are derived from a granitic to granodioritic magma of S-type character which must have formed by anatexis of continental crust. It intruded into a relatively shallow crustal level, 410–420 Ma ago, at the Silurian. Trace element characteristics are consistent with a post-collision geotectonic environment testifying to extensional tectonics at the end of the Caledonian era.
Zusammenfassung Die Orthogneise des Spessartkristallins lassen sich von einem granitischen bis granodioritischen Magma von S-Typ-Charakter ableiten, das durch Anatexis kontinentaler Kruste entstanden sein mu\ und in ein relativ oberflächennahes Krustenniveau intrudierte. Die Platznahme erfolgte vor 410–420 Ma, d. h. im Silur. Die Spurenelement-Muster der Orthogneise entsprechen denen von Post-Kollisions-Granitoiden, was als Hinweis auf eine Phase der Dehnungstektonik am Ende der kaledonischen ära bewertet werden kann.
Résumé Les orthogneiss du Spessart sont dérivés d'un magma granitique à granodioritique de type S qui doit s'Être formé par anatexie de la croûte continentale. Ce magma a été intrudé dans un niveau peu profond de la croûte il y a 410–420 Ma c'est-à-dire au Silurien. La distribution des éléments en traces est en accord avec celle des granitoÏdes formés dans un contexte géodynamique de post-collision. Cette observation est en faveur d'une phase d'extension tectonique à la fin du cycle calédonien.
, — Wojcieszów-Kalke. , — . . , , , , .相似文献
86.
The basement areas in Southeast Libya, South Egypt and North Sudan, west of the Nile, between Gebel Uweinat and the Bayuda Desert, are part of an approximately 1000-km-wide, complexly folded, polymetamorphic zone with a regional N-NNE-NE-ENE trend of foliation and fold axis. Since this belt extends southwestward into the area of Zalingei in the southern Darfur block (West Sudan), it is named the Northern Zalingei fold zone. Sr and Nd isotopic studies suggest that this zone is older than Pan-African and further indicate that, apart from Archean rocks in the Gebel Uweinat area, this belt is of Early-Middle Proterozoic age. An Early-Middle Proterozoic three-stage deformational and anatectic event established the present-day fold and fault geometry in the western parts of this zone in the Gebel Uweinat—Gebel Kamil area. The Pan-African tectono-thermal episode was most effective in the eastern part of the belt, near the boundary with the Nubian Shield volcano-sedimentary-ophiolite-granitoid assemblages. It caused migmatization, granite emplacement, mylonitization and large-scale wrench faulting which was related to Late Proterozoic accretionary and collisional events of the Arabian-Nubian Shield with the margin of the East Saharan Craton. 相似文献
87.
Experimental determination of turbulent fluxes over the heterogeneous LITFASS area: Selected results from the LITFASS-98 experiment 总被引:1,自引:0,他引:1
F. Beyrich S. H. Richter U. Weisensee W. Kohsiek H. Lohse H. A. R. de Bruin Th. Foken M. Göckede F. Berger R. Vogt E. Batchvarova 《Theoretical and Applied Climatology》2002,73(1-2):19-34
Summary ?During the LITFASS-98 experiment, local flux measurements were performed over five different types of underlying surface
(grass, barley, triticale, pine forest, water) in a heterogeneous landscape using eddy covariance and profile techniques over
a three week time period in June, 1998. Estimates of the area-integrated sensible heat flux during daytime were obtained from
continuous measurements with a large aperture scintillometer (LAS) along a 4.7 km path. The calculation of a mean diurnal
cycle of the fluxes during the experiment revealed significant differences between the main land use classes. A land-use weighted
average of the sensible heat flux was found to be in good agreement with the LAS based estimate, which in turn was supported
by other regionally integrated flux estimates from budget considerations and aircraft measurements for a few case studies.
The profiles of turbulent quantities measured along a 99 m-tower significantly deviate from “idealised” profiles measured
over homogeneous terrain. Peculiarities in the profile structure could be attributed to the heterogeneity of the terrain,
namely to the differences in the surface characteristics of the footprint areas for the different tower levels.
Received June 6, 2001; revised January 15, 2002; accepted April 4, 2002 相似文献
88.
89.
The temporal change of the rotation vector of a rotating body is, in the first order, identical in a space-fixed system and
in a body-fixed system. Therefore, if the motion of the rotation axis of the earth relative to a space-fixed system is given
as a function of time, it should be possible to compute its motion relative to an earth-fixed system, and vice versa. This
paper presents such a transformation. Two models of motion of the rotation axis in the space-fixed system are considered:
one consisting only of a regular (i.e., strictly conical) precession and one extended by circular nutation components, which
are superimposed upon the regular precession. The Euler angles describing the orientation of the earth-fixed system with respect
to the space-fixed system are derived by an analytical solution of the kinematical Eulerian differential equations. In the
first case (precession only), this is directly possible, and in the second case (precession and nutation), a solution is achieved
by a perturbation approach, where the result of the first case serves as an approximation and nutation is regarded as a small
perturbation, which is treated in a linearized form. The transformation by means of these Euler angles shows that the rotation
axis performs in the earth-fixed system retrograde conical revolutions with small amplitudes, namely one revolution with a
period of one sidereal day corresponding to precession and one revolution with a period which is slightly smaller or larger
than one sidereal day corresponding to each (prograde or retrograde) circular nutation component. The peculiar feature of
the derivation presented here is the analytical solution of the Eulerian differential equations. 相似文献
90.
We discuss here the spectroscopic properties of the Seyfert 2 galaxy NGC 7130 (= IC 5135). Emission line regions were isolated and line ratios were measured and fitted with photoionization models; this allowed to discriminate between thermal and non thermal ionization in the circumnuclear regions. Massive star formation is likely to occur at projected distances from the nucleus ≫ 2 kpc: line profiles in these regions suggest the presence of outflows of gas due to stellar winds from hot massive stars. 相似文献