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Two pairs of expanded granular sludge bed (EGSB) bioreactors, R1/R2 and R3/R4, were designed. R1/R2 were used for mesophilic (37 degrees C) treatment of synthetic wastewater over a 100-day trial. A successful start-up was achieved by R1 and R2, with COD removal over 90%. Both reactors were operated under identical parameters; however, increased organic loading induced a reduction in COD removal by R1, while R2 maintained satisfactory performance throughout the experiment. R3/R4 were operated at 15 degrees C throughout a 422-day trial and were used for the stabilisation of volatile fatty acid-based wastewater. Phenol was introduced to R4 at an applied loading rate of 1 kg phenol m(-3)d(-1), which was increased to 2 kg phenol m(-3)d(-1). No phenol was supplied to R3. Efficient COD conversion was recorded in both R3 and R4, thus demonstrating the feasibility of high-rate phenol degradation under psychrophilic conditions. Terminal restriction fragment length polymorphism analysis was applied to the characterisation of microbial community dynamics within each of the reactors. The results indicated a microbiological basis for the deviation, in terms of operational performance, of R1 and R2. TRFLP analyses indicated stable microbial communities in R3 and R4, but detected changes in the abundance of specific ribotypes in response to phenol mineralisation. 相似文献
995.
V. V. Skorokhod M. B. Shtern A. V. Kuz’mov A. V. Ragulya 《Powder Metallurgy and Metal Ceramics》2006,45(5-6):221-225
A study has been made on the effects of loading scheme and conditions restricting macroscopic strain on the work-hardening
kinetics and strain accumulation in the solid state in sintering materials with bimodal pore size distributions. Active loading
intensifies the reduction in the small pores. The greatest effect comes from combining sintering with hydrostatic compression.
At the same time, kinematic constraints (partial or complete adhesion in surfaces) substantially retards the shrinkage of
large pores, which means that the porous structure can be controlled.
__________
Translated from Poroshkovaya Metallurgiya, Nos. 5–6(449), pp. 10–15, May–June, 2006. 相似文献
996.
James M. Watkins Ronald Dermott Stephen J. Lozano Edward L. Mills Lars G. Rudstam Jill V. Scharold 《Journal of Great Lakes research》2007,33(3):642-657
The status of invasive dreissenid mussels (Dreissena polymorpha and D. bugensis) and native amphipods (Diporeia spp.) in Lake Ontario was assessed in 2003 and compared with historical data. D. polymorpha (zebra mussels) were rarely observed in 2003, having been displaced by D. bugensis (quagga mussels). D. bugensis expanded its depth range from 38 m depth in 1995 to 174 m in 2003 and this dreissenid reached densities averaging 8,000/m2 at all sites < 90 m. During the same time period, Diporeia populations almost completely disappeared from 0–90 m depth, continuing a declining trend from 1994–1997 reported in previous studies. The average density of Diporeia in the 30–90 m depth interval decreased from 1,380/m2 to 63/m2 between 1997 and 2003. Prior to 2003, areas deeper than 90 m represented a refuge for Diporeia, but even these deep populations decreased, with densities declining from 2,181/m2 in 1999 to 545/m2 in 2003. Two common hypotheses for the decline of Diporeia in the Great Lakes are food limitation and a toxin/pathogen associated with dreissenid pseudofeces. The Diporeia decline in deep waters preceded the expansion of D. bugensis to these depths, and suggests that shallow dreissenid populations remotely influence profundal habitats. This pattern of decline is consistent with mechanisms that act from some distance including nearshore dreissenid grazing and downslope transport of pseudofeces. 相似文献
997.
V. F. Solinov 《Glass and Ceramics》2007,64(5-6):149-152
Studies have shown that when smaller NiS inclusions are present the “heat-soak” method of rejecting toughened glasses does
not completely guarantee that these glasses cannot fail spontaneously while in use. It is posited that the reason why glasses
fail spontaneously is not so much the polymorphism of NiS as high stresses around NiS inclusions and, in consequence, a limitation
on the “life” time of glass in accordance with the kinetic theory of long-term strength.
__________
Translated from Steklo i Keramika, No. 5, pp. 3–6, May, 2007. 相似文献
998.
999.
I. V. Brusilovskii V. D. Vermel' V. V. Mitrofovich Yu. G. Moskovko 《Chemical and Petroleum Engineering》1992,28(3):159-161
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 3, pp. 8–9, March, 1992. 相似文献
1000.
Lévy F.; Kendrick K. M.; Keverne E. B.; Piketty V.; Poindron P. 《Canadian Metallurgical Quarterly》1992,106(2):427
Measurement of cerebrospinal concentrations of oxytocin (OT) in intact and peridural-anesthetized ewes showed that central release of OT during parturition is inhibited by this anesthesia. Also, observations of maternal behavior and attraction to amniotic fluid (AF) in inexperienced peridural-anesthetized parturient ewes after intracerebroventricular injections of either OT (2?×?10 μg) or saline showed that OT infusions increased the proportion of maternal females (2/17 vs 10/20; p?=?.01) and attraction to AF. This study confirms that in sheep vaginocervical stimulation activates the oxytocinergic system, which induces the onset of maternal behavior, and that this action is not limited to maternally experienced females. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献