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91.
92.
In the present work the kinetics and the feasibility of batch anaerobic filter operations for the treatment of beet molasses distillery slops have been investigated. Up to 50% of the influent COD up to 25 g/l are removed after 5… 10 h and up to 80% after 24… 40 h treating time. Highest removal rates were obtained for 50% removal and influent COD concentration ≧13 kg. m?3. The highest methane productivity was observed in the same range of COD influent concentration during the first 10 hours (initial velocity) of the treatment. The benefits of the anaerobic treatment of waste water applying systems with biomass retention are discussed. 相似文献
93.
D. Engelbart H. Steinhagen U. Görsdorf J. Neisser H. J. Kirtzel G. Peters 《Meteorology and Atmospheric Physics》1999,71(1-2):61-68
Summary At a special measuring site for boundary-layer studies as well as land-surface processes the Meteorological Observatory Lindenberg
of the German Weather Service (DWD) has recently put into operation a newly-desi gned phased-array SODAR/RASS, which has been
developed by METEK on behalf of the DWD. This system provides the vertical profiles of the three-di mensional wind vector
in the boundary layer on an operational basis and is furthermore suitable for getting information on the profile of virtual
temperature up to about 400 m in height based on the addition of RASS components. The following paper describes both the technique
of this SODAR/RASS and the various modes of operation as well as the different options in managing the system. First evaluations
on the data availability concerning the maximum height coverage will give an impression on the system’s capabilities. Finally,
the accuracy of the derived profiles of winds and temperature will be investigated by means of comparisons of the SODAR/RASS
data with measurements of a six-sonde tethered-balloon system as well as meteorological data of a 99 m tower in the vicinity
of the system.
Received November 27, 1998 Revised April 9, 1999 相似文献
94.
95.
This paper reviews the socio-economic and ecological context of Fijian reef fisheries. This review is deemed necessary because improved understanding of the state and trends of Fiji's coral reef fisheries on a national level is required for designing an effective management plan for Fiji's inshore reef fisheries. The most important point that emerges from our review is that despite numerous studies of Fiji's reef fisheries, the current status of reef-associated fisheries at the national level is still uncertain due, mainly, to the lack of dependable data on the subsistence fisheries. This in turn leads to uncertainty about how the continuation of fishing, in particular, fishing focused on target species for the coral reef resources trade, will affect fishing communities and the ecosystem. 相似文献
96.
R. G. Gratton G. Bonanno P. Bruno A. CalÍ R. U. Claudi R. Cosentino S. Desidera F. Diego G. Farisato G. Martorana M. Rebeschini S. Scuderi 《Experimental Astronomy》2001,12(2):107-143
SARG is a cross dispersed echelle spectrograph in operation since late spring 2000 at the Italian Telescopio Nazionale Galileo
(TNG) 3.5 m telescope, La Palma. SARG offers both single object and long slit (up to 26 arcsec) observing modes covering a
spectral range from λ = 0.37 up to1 μm, with resolution ranging from R = 29,000 up to R = 164,000. Cross dispersion is provided by means of a selection of four grisms; interference filters may be used for the
long slit mode (up to 26 arcsec). A dioptric camera images the cross dispersed spectra onto a mosaic of two 2048 × 4096 EEV
CCDs (pixel size: 13.5 μm) allowing complete spectral coverage at all resolving power for λ < 0.8 μm. In order to reach a
high wavelength calibration precision an iodine-absorbing cell is provided. A Distributed Active Temperature Control System
(DATCS) maintains constant the temperature of all spectrograph components at a preset value. Early results show that SARG
works according to original specifications in terms of wavelength coverage, efficiency (measured peak efficiency is about
13%),resolution (maximum resolution R = 164,000 using a 0.3 arcsec slit, R ∼144,000 using an image slicer), and stability (preliminary estimates of radial velocity accuracy is ∼3 m/s using the iodine
cell and ±150 m/s without the iodine cell).
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
97.
The reflectance coefficient of the regolith layer of celestial bodies has been studied in relation to the physical properties of regolith particles (size, refractive index, and packing density) on the basis of an accurate numerical radiative-transfer algorithm for a semi-infinite flat layer. Using the geometric-optics approximation, we have found that a shape mixture of randomly oriented spheroids can successfully model the single-scattering phase function of independent soil grains. In order to take into account the effect of packing density in a regolith layer, the concept of the so-called static structure factor was used. The main effect of increasing packing density is to suppress the forward-scattering peak of the phase function and to increase the albedo of the reflecting surface. We also investigated the influence of fine dust on the reflected light. An addition of small particles not only increases the surface albedo, but also changes the brightness profile and enhances the backscattering. Although the problem of unique solution, which is inherent in the retrieval of the properties of a medium from the measurements of the intensity of light scattered by this media, cannot be removed in the proposed model, the procedure used here, in contrast to widely used approximations, allows us to fit observational data with a set of real characteristics of the regolith. Semiempirical approaches are able to fit the measurements well with a small number of free parameters, but they do not explicitly contain crucial physical characteristics of the regolith such as grain sizes or the refractive index. We compared the numerical solution of the radiative-transfer equation with the Hapke approximation, which is most often used by investigators. The errors introduced by the Hapke model are small only for near-isotropic scattering by isolated particles. However, independent regolith grains are known to scatter light mainly in the forward direction. 相似文献
98.
A. R. King K. Schenker U. Kolb M. B. Davies 《Monthly notices of the Royal Astronomical Society》2001,321(2):327-332
We show that the usual picture of supersoft X-ray binary evolution as driven by conservative thermal time-scale mass transfer cannot explain the short orbital periods of RX J0537.7–7034 (3.5 h) and 1E 0035.4–7230 (4.1 h). Non-conservative evolution may produce such periods, but requires very significant mass loss, and is highly constrained. 相似文献
99.
100.