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81.
Summary Evaporation from an area covered with short clover-grass has been determined by means of evapotranspirometers (4 m2), open (12 m2) and screened (1/3 m2) evaporimeters, and it has been estimated on the basis ofPenman's andThornthwaite's theories, too. The results of the measurements with the various instruments are compared with each other and with the results derived from the cited theories.Further, radiation heat balances have been made, including evaporation and heating of soil and atmosphere.
Zusammenfassung Die Verdunstung über einer mit kurzem Kleegras bedeckten Fläche wurde mittels Evapotranspirometern (4 m2), offenen (12 m2) und abgeschirmten (1/3 m2) Evaporimetern gemessen und auch auf Grund vonPenmans undThornthwaites Theorien berechnet. Die Meßergebnisse der verschiedenen Instrumente werden untereinander verglichen und auch den mittels der angeführten Theorien abgeleiteten Resultaten gegenübergestellt.Weiters wurde eine Strahlungs-Wärme-Bilanz aufgestellt, die auch die Verdunstung und die Erwärmung von Boden und Atmosphäre berücksichtigt.

Résumé On a mesuré l'évaporation sur une surface recouverte de trèfle court à l'aide d'évapotranspiromètres (4 m2) et d'évaporimètres ouverts (12 m2) et protégés (1/3 m2); les résultats de mesures, furent comparés entre eux et avec la théorie dePenman etThornthwaite.Puis on a dressé un bilan radiatif tenant compte, de l'évaporation et du réchauffement du sol et de l'atmosphère.


With 8 Figures  相似文献   
82.
With the aid of a statistical approach regarding only the nearest optical object to a given radio position we have found identification rates of nearly 30 per cent up to the blue and red limits of the Palomar Sky Survey prints covering the region of the 5C4 radio survey. Roughly 60 per cent of these identifications are blue starlike objects and therefore possible quasar candidates. The remainig identifications are galaxies. Probabilities for the first neighbours to be an optical counterpart and finding charts for highly reliable objects are given.  相似文献   
83.
The structural relationships of several intrusive sheets belonging to the extensive metadolerite suite of the Appin (lower) Dalradian rocks of the Creeslough area, northwest Donegal, Ireland have been examined. It is concluded that, relative to the regional chronology of deformation of the enclosing metasediments, sheet emplacement has occurred: pre-D2; syn-D2; between D2 and D3; and syn-D3. The height of activity came in the post-D2, pre-D3 interval and coincided with the peak of regional metamorphism in the area. These relationships in Donegal are compared with those of the pretectonic basic rocks of the southwest Highlands and models are discussed.  相似文献   
84.
In some recent papers the old cosmological hypothesis by FREUNDLICH about tired photons as a consequence of a „scattering of light on light”︁ is proposed, once more. The new formulation of the hypothesis supposes the existence of the third scalar mode of photons, and the hypothesis also supposes that the scalar photons have no interaction with the matter, but that the scalar photons strongly interact with the vectorial photons. We prove that this hypothesis is in contradiction to the laws of heat radiation. The value of the constant a in the STEFAN -BOLTZMANN law becomes by a factor 3/2 larger than the value of a according to PLANCK'S law.  相似文献   
85.
In the present paper revised distances of optical objects from radio sources of the 5C2 survey are given. A statistical investigation of the data is given for blue objects and galaxies by the statistical method of the “first neighbour”. The identification rate on blue plates for both the blue objects and galaxies amounts to about 40% out of the total number of 26 identifications. For every blue object and galaxy which are proposed as an identification the statistical reliability is given.  相似文献   
86.
Nitrogen-containing heterocyclic compounds are fundamental biochemical components of all life on Earth and, presumably, life elsewhere in our solar system. Dete...  相似文献   
87.
We have measured P- and S-wave velocities on two amphibolite and two gneiss samples from the Kola superdeep borehole as a function of pressure (up to 600 MPa) and temperature (up to 600 °C). The velocity measurements include compressional (Vp) and shear wave velocities (Vs1, Vs2) propagating in three orthogonal directions which were in general not parallel to inherent rock symmetry axes or planes. The measurements are accompanied by 3D-velocities calculations based on lattice preferred orientation (LPO) obtained by TOF (Time Of Flight) neutron diffraction analysis which allows the investigation of bulk volumes up to several cubic centimetres due to the high penetration depth of neutrons. The LPO-based numerical velocity calculations give important information on the different contribution of the various rock-forming minerals to bulk elastic anisotropy and on the relations of seismic anisotropy, shear wave splitting, and shear wave polarization to the structural reference frame (foliation and lineation). Comparison with measured velocities obtained for the three propagation directions that were not in accordance with the structural frame of the rocks (foliation and lineation) demonstrate that for shear waves propagating through anisotropic rocks the vibration directions are as important as the propagation directions. The study demonstrates that proper measurement of shear wave splitting by means of two orthogonal polarized sending and receiving shear wave transducers is only possible when their propagation and polarization directions are parallel and normal to foliation and lineation, respectively.  相似文献   
88.
The seismic ground motion of a test area in the eastern district of Naples is computed with a hybrid technique based on the mode summation and the finite difference methods. This technique allows us the realistic modelling of source and propagation effects, including local soil conditions. In the modelling, we consider the 1980 Irpinia earthquake, a good example of strong shaking for the area of Naples, which is located about 90 km from the epicenter.The detailed geological setting is reconstructed from a large number of drillings. The sub-soil is mainly formed by alluvial (ash, stratified sand and peat) and pyroclastic materials overlying a pyroclastic rock (yellow neapolitan tuff), representing the neapolitan bedrock. The detailed information available on mechanical properties of the sub-soil and its geometry warrants the application of the sophisticated hybrid technique.As expected, the sedimentary cover causes an increase of the signal's amplitudes and duration. If thin peat layers are present, the amplification effects are reduced, and the peak ground accelerations are similar to those observed for the bedrock model. This can be explained by the backscattering of wave energy at such layers, that tend to seismically decouple the upper from the lower part of the structure.For SH-waves, the influence of the variations of the S-wave velocities on the spectral amplification is studied, by considering locally measured velocities and values determined from near-by down-hole measurements. The comparison between the computed spectral amplifications confirms the key role of an accurate determination of the seismic velocities of the different layers.The comparison performed between a realistic 2-D seismic response and a standard 1-D response, based on the vertical propagation of waves in a plane layered structure, shows considerable difference, from which it is evident that serious caution must be taken in the modelling of expected ground motion at a specific site.  相似文献   
89.
ALHA 77005, a shocked achondrite of the shergottite group, is unique in containing cumulus olivine crystals which display a brownish color in thin section. Mössbauer, EPR, and optical spectroscopic studies show the presence of Fe3+ in the olivine. Approximately 4.5 wt.% of the total iron in the olivine (24 wt.% as FeO) is in the trivalent state. The Fe3+ ions preferentially occupy M2 lattice positions. Charge transfer between Fe3+ and Fe2+ as well as between Fe3+ and oxygen ligands causes a broad absorption band in the optical spectrum at high energies which is the reason for the olivine color. It is concluded that the color of the ALHA 77005 olivine is preterrestrial and may be the result of shock-induced oxidation of the olivine crystals on the meteorite parent body.  相似文献   
90.
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