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O3是一种强氧化剂。利用臭氧处理带色有机废水。可以脱色,而且可以降低废水COD。采用O3氧化脱色速度快,效果好,对废水的脱色废可达80%以上,这是通常的混凝处理通信以达到的。如果采用通臭氧和混凝联合处理,处理效果会更好,脱色率可提高到95%以上。 相似文献
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Dr. Lon D. Drake 《Environmental geochemistry and health》1983,5(1):15-19
In the last three years, twelve orphan coal surface mines in Iowa, USA, have been reclaimed under the Federal Rural Abandoned Mine Program (RAMP) by smoothing highly acid spoils, covering the spoils with a thin dirt layer and planting a cover crop. Ten years ago a test plot was designed with a wedge of loess over acid spoils. Subsequent observation suggests that on the new RAMP sites, acidified throughflow and discharge of shallow soil moisture and groundwater will gradually kill the vegetation in the lower valleys and erosion will proceed upvalley as a migrating knickpoint. The problem might be eliminated by directing the acidified throughflow beneath the cover material, in sand underdrains or tile lines in the main drainages. The discharge could either be diluted in a nearby creek, if adequate flow is available, or neutralised in a basin paved with limestone rip-rap. Vegetation which was found to be especially well adapted to thin cover sites includes native prairie grasses, crownvetch and cattails. Sphagnum mosses may also offer some possibilities for such locations. A RAMP reclamation site should be designed as an experimental area to test these methods and determine their cost. These recommendations may also be applicable in other mining areas. 相似文献
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David W. Martin John B. Braden J. Lon Carlson 《Journal of the Air & Waste Management Association (1995)》2013,63(2):211-216
Abstract When forecasting the impacts of pollution control regulations upon industries which produce pollutants jointly with ordinary outputs, potential input and production process adjustments must be identified and assessed. The problem addressed here is that the empirical approximation of Joint production processes by a single-equation Least Squares (LS) regression misrepresents restrictions on input substitution possibilities. In such cases, some inputs are allocated to both production processes, which provides the jointness. But other inputs contribute to only one process and do not contribute to adjustment opportunities in the other process. Since single-equation LS regression assumes that all inputs can be substituted throughout the production process, its application results in a misspecified empirical model. This paper presents a theoretical framework that motivates the use of Seemingly Unrelated Regression (SUR) estimators to directly approximate such processes. The advantage to using the SUR estimators is that they exploit the related nature of the input decisions so that a more accurate model of the processes can be estimated. The framework is demonstrated with an application to the case of SO2 abatement by coal-fired electricity generating units. The results indicate that these units could efficiently burn more low-BTU, low-sulfur coal to maintain the same electricity output with a lower SO2 emission rate. More generally, this application demonstrates the usefulness of the framework developed here. 相似文献
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本文提出了在一定条件下用NaF或用EDTA掩蔽易于水解的Fe^3+后,用中和法测定聚合硫酸铁的碱化度。对两种方法进行了比较,均能获得满意的结果。 相似文献
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Prioritisation of organic contaminants in a river basin using chemical analyses and bioassays 总被引:1,自引:1,他引:0
Smital T Terzić S Lončar J Senta I Žaja R Popović M Mikac I Tollefsen KE Thomas KV Ahel M 《Environmental science and pollution research international》2013,20(3):1384-1395
Region-specific contaminant prioritisation is an important prerequisite for sustainable and cost-effective monitoring due to the high number of different contaminants that may be present. Surface water and sediment samples from the Sava River, Croatia, were collected at four locations covering a 150-km-long river section characterised by well-defined pollution gradients. Analysis of contaminant profiles along the pollution gradients was performed by combining toxicity screening using a battery of small-scale or in vitro bioassays, which covered different modes of action, with detailed chemical characterisation based on gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). A large number of contaminants, belonging to different toxicant classes, were identified in both analysed matrices. Analyses of water samples showed that contaminants having polar character occurred in the highest concentrations, while in sediments, contributions from both non-polar and amphiphilic contaminants should be taken into account. Estimated contributions of individual contaminant classes to the overall toxicity indicated that, besides the classical pollutants, a number of emerging contaminants, including surfactants, pharmaceuticals, personal care products and plasticizers, should be taken into consideration in future monitoring activities. This work demonstrates the importance of the integrated chemical and bioanalytical approach for a systematic region-specific pollutant prioritisation. Finally, the results presented in this study confirm that hazard assessment in complex environmental matrices should be directed towards identification of key pollutants, rather than focusing on a priori selected contaminants alone. 相似文献
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Lon Drake 《Environmental geochemistry and health》1986,8(3):62-67
Many abandoned strip-mine sites in midwestern USA are highly acidic and require a separate layer of low-acidity cover materials
for successful revegetation. Economics and logistics often constrain this reclamation to a very thin cover. Twenty-two species
of shrubs and trees were tested for 6 years of survival and growth on a thin wedge of silt loess (up to 0.75m thick) emplaced
over highly acid spoils, in south-central Iowa. No weed control or maintenance was provided. The performance of 21 of the
species could be categorized into 3 groups: Group 1-consistent survival (10 species); Group 2-irregular survival and growth
(6 species); Group 3-little suitability for survival (5 species). Mouldy nursery stock precluded evaluation of 1 species.
For most species, the most favourable survival and growth was not on the thickest loess cover (0.75 meters) because weeds
became too well established. In general, the shrubs survived severe weed competition in dwarfed form until they could break
through the weed canopy. But the tree species had to penetrate the weed canopy within their first few years of growth or perish.
There is evidence that if weed competition were reduced or eliminated, the species in Group 2 would probably have survival
and growth equivalent to those in Group 1. The use of “tubelings” for establishing shrubs and trees on thincover reclamation
sites is suggested. 相似文献
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