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161.
A. V. Ivanov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2007,41(6):327-331
Successful introduction of pisciculture to reservoirs by the method of migratory fish-farm pasturing is described.
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Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 9, September 2007, pp. 36–40. 相似文献
162.
163.
Journal of Quantitative Economics - The paper tries to apply a new technique — the decomposition principle — to centre state financial relations in India. As, appropriate data are not... 相似文献
164.
Pilot experiments with electrodialysis and ozonation for the production of a fertiliser from urine. 总被引:1,自引:0,他引:1
W Pronk S Zuleeg J Lienert B Escher M Koller A Berner G Koch M Boller 《Water science and technology》2007,56(5):219-227
Pilot tests were performed with a process combination of electrodialysis and ozonation for the removal of micropollutants and the concentration of nutrients in urine. In continuous and batch experiments, maximum concentration factors up to 3.5 and 4.1 were obtained, respectively. The desalination capacity did not decrease significantly during continuous operation periods of several weeks. Membrane cleaning after 195 days resulted in approximately 35% increase in desalination rate. The Yeast Estrogen Screen (YES), a bioassay that selectively detects oestrogenic compounds, confirmed that about 90% of the oestrogenic activity was removed by electrodialysis. HPLC analysis showed that ibuprofen was removed to a high extent, while other micropollutants were below the detection limit. In view of the fact that ibuprofen is among the most rapidly transported micropollutants in electrodialysis processes, this result indicates that electrodialysis provides an effective barrier for micropollutants. Standardised plant growth tests were performed in the field with the salt solution resulting from the treatment by electrodialysis and subsequent ozonation. The results show that the plant height is comparable to synthetic fertilisers, but the crop yield is slightly lower. The latter is probably caused by volatilisation losses during field application, which can be prevented by improved application technologies. 相似文献
165.
Hugo A. Keuzenkamp 《Journal of economic surveys》1995,9(2):233-248
Books reviewed in this article: David F. Hendry (1993) Econometrics: Alchemy or Science? Essays in Econometric Methodology 相似文献
166.
167.
This paper provides some new evidence on the behaviour of cross-country growth rates. We reject the linear model commonly used to study cross-country growth behaviour in favour of a multiple regime alternative in which different economies obey different linear models when grouped according to initial conditions. Further, the marginal product of capital is shown to vary with the level of economic development. These results are consistent with growth models which exhibit multiple steady states. Our results call into question inferences that have been made in favour of the convergence hypothesis and further suggest that the explanatory power of the Solow growth model may be enhanced with a theory of aggregate production function differences. 相似文献
168.
Kuzmenko A. P. Saburov S. V. Korolenko L. A. Shutko V. P. 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2021,55(4):487-493
Power Technology and Engineering - The results of processing annual data of the automated seismometric monitoring system (ASMS) of the Zeya HPP are presented. They are compared with the results of... 相似文献
169.
Astashev M. G. Panfilov D. I. Rozhkov A. N. Petrov M. I. Rashitov P. A. Gorchakov A. V. 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2021,55(4):625-632
Power Technology and Engineering - The paper presents the results of developing a high-speed semiconductor transformer voltage regulator (STVR) intended for a real-time voltage regulation of 0.4 kV... 相似文献
170.
A. S. Zalesov S. E. Lisichkin 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1990,24(3):221-226
1. | The suggestions on calculating the strength of concrete joints with transverse reinforcements were made on the basis of using the method of secondary stress fields and permit more complete consideration of the effect of the characteristics of the stress state on the strength of massive members. |
2. | Unlike the preceding developments, the present suggestions make it possible to evaluate the reinforcement and concrete strength of the structural member being designed with pin resistance of the transverse bar reinforcement to the effect of the initial and secondary shear stresses in the longitudinal joint. |
3. | The installation of an additional amount of transverse reinforcement precludes the probability of separation of the massive member along the longitudinal block joint and provides reliable and safe operation of the structure. |