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371.
Bioventing is a relatively new technology that uses forced air movement to deliver supplemental oxygen to contaminated soils to stimulate the biodegradation of contaminants by indigenous microorganisms. A bioventing pilot test was initiated at Offutt Air Force Base, Nebraska, in August 1992, at a site contaminated with jet fuel. Air was injected into the subsurface over a period of 15 months, and tests were conducted at 6 months, and again at 15 months, to determine the effectiveness of the system. This article describes the bioventing process and its application at this test site. The results of the pilot test are discussed to illustrate the extent of the remediation accomplished through bioventing. 相似文献
372.
Frank C. Krysiak Daniela Krysiak 《Journal of Environmental Economics and Management》2003,46(3):513-538
This paper analyzes the consequences of integrating the conservation laws of mass and energy into the microeconomic models of production, consumption, and general equilibrium. We show that abstract models and especially general equilibrium theory are consistent with these physical constraints, but most applied and environmental economic models are not. We analyze the consequences of physical conservation laws for substitution possibilities and show that these constraints limit the number of independent substitution processes but not the value of the substitution elasticities. Finally, we propose a method for integrating physical constraints into static microeconomic models with a minimum of changes. 相似文献
373.
Antoon Opperhulzen Els W. v. d. Volde Frank A. P. C. Gobas Djlen A. K. Liem Jan M. D. v. d. Steen 《Chemosphere》1985,14(11-12)
Most polychlorinated naphthalones (PCN) accumulate rapidly according to their hydrophobicity. The uptake and ellmination rate constants are comparable to those of chlorinated benzenes and biphenyls.For most PCN-congeners the resulting bioaccumulation factors show an increase with increasing hydrophobicity. For higher Kd,oct-values (>105) however, no further increase of Kc is observed (Kc. max. = 3.5.104).For the two hepta- and the octachloronaphthalenes no detectable concentrations are found in the fishes, although no restricted blo-availability could be expected. Based on these observations and on data obtained from the literature. a loss of membrane permeation is suggested for hydrophobic molecules with widths over 9.5 Å.In addition a membrane permeation model, as part of the accumulation process of hydrophobic chemicals. Is proposed, which is based on diffusion and partition processes. 相似文献
374.
Frank Pobell 《Die Naturwissenschaften》1987,74(4):168-174
375.
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377.
An operating Pd//D2O, Li+, Cl−//Pt cell, placed in an external electrostatic field, yielded unexpected results, viz. (i) Morphological changes in the form
of discrete sites exhibiting molten-like features, i.e. features that require substantial energy expenditure. (ii) Presence
of elements (Al, Mg, Ca, Si, Zn, ...) that could not be extracted from cell components and deposited on discrete sites. The
cell design and the experimental protocol assuring reproducibility is described in detail. 相似文献
378.
379.
Frank Clark Dr Jan E. Dickinson Barry N. J. Walters Lorraine R. Marshall Peter C. O'Leary 《黑龙江环境通报》1995,15(11):1035-1039
An association is described between women with lupus anticoagulant and abnormal prenatal serum screening results. Three cases of positive second-trimester serum screening for Down syndrome, with karyotypically normal fetuses, in women demonstrated to have lupus anticoagulant are presented. Serum screening positivity was principally due to a disproportionately elevated maternal serum human chorionic gonadotrophin (hCG) level. In each case, early, severe intrauterine growth restriction was documented, with only one fetus surviving the neonatal period. As maternal lupus anticoagulant may have a profoundly adverse effect on the course of pregnancy, we suggest that an elevated hCG level on prenatal screening prompt consideration of maternal lupus anticoagulant testing if ultrasonography demonstrates an otherwise normal singleton gestation and the fetal karyotype is normal. 相似文献
380.