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1.
On the effect of spatial variances in historical rainfall time series to CSO performance evaluation.
Historical, high-resolution rain series are the backbone of modern combined sewer overflow (CSO) structure design. These rain series are the input to the computational estimation of the performance of the measures with respect to CSO pollution abatement. However, those historical precipitation measurements are available at only a few locations. Frequently rain series have to be used from gauging stations at a significant distance. In order to judge and to compensate for this influence an estimate between rain characteristics and combined sewer outflow (CSO) performance indicators would be useful. In this paper such correlations have been sought for a collection of 37 rain series covering large areas of Europe. It was found that the mean annual rain volume can explain most of the variances for the performance indicators Number of overflows and CSO volume. For explaining the spatial differences in the efficiency of the CSO structure another rain characteristic, i.e. the maximum event with a return period of one year, is to be used. 相似文献
2.
This paper presents results of a research project, in which a process-dependent real-time control (RTC) strategy for a sequencing batch reactor plant was realised in full-scale. The cycle controller is based on NH4 analysers, NO3 probes, TSS probes and sludge level probes. With this new RTC strategy it was possible to increase the treatment capacity by 50%. By implementation of the new controller the TN, TP and NH4-N treatment efficiency could be improved significantly, too. The treatment efficiency concerning COD is comparable. 相似文献
3.
The purpose of this brief editorial is to discuss psychology in Québec and some of the foremost researchers who have had a recognized world-wide impact on psychology. Following a brief review of historical facts describing the evolution of psychology in Québec, and of issues related to communicating psychology in French, the contribution of certain distinguished individuals is highlighted. These persons either have played a critical role in international organisations, or have produced scientific work that is widely recognized by their peers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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We have localized gene MSS51 on chromosome XII of Saccharomyces cerevisiae between the RDN1 and CDC42 loci. 'Head to head' with MSS51 is another gene, QRI5, the function of which is unknown. However, the proximity of these genes, the structure of the intergenic region and the presence of an ABF1 binding site right in the middle of this region suggest that the MSS51 and QRI5 expressions are submitted to a common regulatory process. 相似文献
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The cure of a liquid dicyanate ester monomer, which reacts to form a high-Tg (≈200°C) polycyanurate network, has been investigated using differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and a dynamic mechanical technique, torsional braid analysis (TBA). The monomer is cured with and without catalyst. The same one-to-one relationship between fractional conversion and the dimensionless glass transition temperature is found from DSC data for both the uncatalyzed and catalyzed systems, independent of cure temperature, signifying that the same polymeric structure is produced. Tg is the parameter used to monitor the curing reactions since it is uniquely related to conversion, is sensitive, is accurately determined, and is also directly related to the solidification process. The rate of uncatalyzed reaction is found to be much slower than that of the catalyzed reaction. The apparent overall activation energy for the uncatalyzed reaction is found to be greater than that of the catalyzed reaction (22 and 13 kcal/mol, respectively) from time–temperature superposition of experimental isothermal Tg vs. In time data to form kinetically-controlled master curves for the two systems. Although the time–temperature superposition analysis does not necessitate knowledge of the rate expression, it has limitations, because if the curing process consists of parallel reactions with different activation energies, as is considered to be the case from analysis of the FTIR data, there should not be a kinetically-controlled master curve. Consequently, a kinetic model, which can be satisfactorily extrapolated, is developed from FTIR isothermal cure studies of the uncatalyzed reaction. The FTIR data for the uncatalyzed system at high cure temperatures, where the material is in the liquid or rubbery states throughout cure, 190 to 220°C, are fitted by a model of two parallel reactions, which are second-order and second-order autocatalytic (with activation energies of 11 and 29 kcal/mol), respectively. Using the model parameters determined from the FTIR studies and the relationship between Tg and conversion from DSC studies, Tg, vs. time curves are calculated for the uncatalyzed system and found to agree with DSC experimental results for isothermal cure temperatures from 120 to 200°C to even beyond vitrification. The DSC data for the catalyzed system are also described by the same kinetic model after incorporating changes in the pre-exponential frequency factors (due to the higher concentration of catalyst) and after incorporating diffusion-control, which occurs prior to vitrification in the catalyzed system (but well after vitrification in the uncatalyzed system). Time–temperature-transformation (TTT) isothermal cure diagrams for both systems are calculated from the kinetic model and compared to experimental TBA data. Experimental gelation is found to occur at a conversion of approximately 64% in the catalyzed system by comparison of experimental macroscopic gelation at the various curing temperatures and iso-Tg (iso-conversion) curves calculated from the kinetic model. © 1993 John Wiley & Sons, Inc. 相似文献
10.
The β and γ decay of uranium atoms from xUO3(100 - x)[3B2O3 · MO] glass systems, where M=Sr or Pb and 0 ≤ × ≤ 20 mol%, is investigated. The γ decay data are very close to each other, for the same UO3 contents, in both the systems. The composition dependence of the β decay exhibits a lower slope in the lead borate matrix than in the strontium borate matrix. The ratio between the β activity of samples with the same uranium ion concentrations in the two investigated glass systems is a function of the x values. The results are correlated with the amount of radioactive nuclides and with the structural environments of the radionuclides. The leaching treatment in water at temperatures below 100°C evidenced no aqueous dissolution of glass samples. 相似文献