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141.
Samples from industrial and domestic emissions and materials were investigated by using in vitro assays for dioxin-like-response (DLR) and chemical analysis. The results show a small part of persistent bioaccumulative toxicants (PBT) to be responsive in vitro. Clean-up procedures directed to persistence decrease the amount of inducing toxicants substantially. The comparison of biological in vitro (B) and chemical (A) analysis show ratios between B and A below 10 for DLR of persistent inductors. The consideration of PAH improved the knowledge about unknown less persistent agonists. 相似文献
142.
Data from the literature on dry deposition of SO2 to various common materials in outdoor atmospheres are reviewed and presented in the context of a theoretical model. The model postulates two resistances to deposition: the aerodynamic resistance, controlled by atmospheric properties; and the surface resistance, controlled by the chemistry of the surface and its moisture layer. Since the dissolution of SO2 is sensitive to pH, buffering of the moisture layer by corrosion products is essential for SO2 deposition to continue. Thus, it is hypothesized that SO2 deposits preferentially on those surfaces that are sensitive to SO2 attack. Based on extant data, estimates of aerodynamic and surface resistances are derived from the literature and maximum \"dry\" deposition rates for SO2 are estimated. Such information could be used to formulate SO2 dose-response or \"damage\" functions for certain materials, based on short-term laboratory tests. 相似文献
143.
Adenosine triphosphate (ATP) content and carbon dioxide (CO2) production in soil vary considerably, depending on soil type, water content, light, stirring of soil, storage conditions, date of sampling, and chemicals added. In most soils, the biomass calculated on the basis of ATP-content was in line with that calculated on the basis of CO2-production. 相似文献
144.
A lidar study of the dispersion of the effluent from the tall (245-m) stacks of Keystone Generating Station in western Pennsylvania was conducted with the aid of two field experiments in May and October 1968. The observations, which were mostly obtained during stable conditions in the morning hours, reveal in detail the important plume characteristics that must be included in a realistic diffusion model for plumes from tall stacks:
- 1.(1) fanning and tilting due to wind veering with height.
- 2.(2) fumigation, which brings high concentrations to ground level in a pattern which, because of the tilting, progresses with time from the left to the right of the plume looking downwind.
- 3.(3) plume trapping by elevated stable layers.
145.
146.
William A. McClenny S. Mark Schmidt Keith G. Kronmiller 《Journal of the Air & Waste Management Association (1995)》2013,63(1):64-69
ABSTRACT Dalton's law of partial pressures and the hypothesis that water vapor equilibrium in a canister is identical to that established above liquid water are used to predict the variation of the percent relative humidity (%RH) of air released from canisters used in ambient air sampling, typically 6-L canisters pressurized with 18 L of air. When (and if) the water vapor partial pressure in a canister exceeds its saturation vapor pressure, water vapor condensation begins and the condensation rate equals the sampling rate of water vapor into the canister. Under constant temperature conditions, the air subsequently released from the canister is less humid than the original sample, following the relationship %RH = 100% (6 L/Vs) for Vs> Vr, where Vs is the residual air volume (referenced to atmospheric pressure), and Vr is shown to depend on the %RH of the ambient air sample. Vr is the residual air volume at which water is completely removed (except for adsorbed water vapor) from the canister wall. For Vs < Vr, the predicted %RH is constant and equal to its value at Vr. Experimental values agree reasonably well with predictions at both high (90%) and low (34%) RH. However, experimental values are often slightly displaced (usually towards lower values of %RH) for mid-range %RH (61%) and variations in %RH near Vr change from canister to canister. 相似文献
147.
148.
149.
D S Diehl R T Denho M N Bhatla W D Sitman 《Journal - Water Pollution Control Federation》1971,43(11):2254-2270
150.
A new and innovative process for the biotechnological production of L-lysine is presented, exemplified here by the fermentative production of the feed additive Biolys60. The novel feature of this product is that the entire manufacturing concept, i.e. the production strain, the raw materials, all process stages and the product specifications have been systematically tailored for optimal environmental compatibility and for minimum resource depletion and waste. The process completely dispenses with the need to discharge residual and waste material and reduces the handling of hazardous materials to a minimum. Since only a few process stages are involved, the method is economical to use and investment outlay is reduced. The process, which also leads to a higher grade product, is thus highly attractive in both ecological and economical terms. By boosting the nutrient value of the plant-based feedstuffs, the product itself makes an cost-effective contribution towards a more sustainable form of animal feeding and by reducing nitrogen emission levels promotes a more environmentally compatible form of animal husbandry. 相似文献