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21.
Treatment of strongflow wool scouring effluent by biological emulsion destabilisation 总被引:4,自引:0,他引:4
The stable oil-in-water emulsion contained in wool scouring effluent was destabilised by aerobic biological treatment as the basis of a potential new effluent treatment process. The de-emulsified wool wax, which is recalcitrant to biodegradation, can then be readily removed by centrifugation. In 12-day batch experiments, 97% of wool wax and 87% of COD were removed after gentle centrifuging at 200 x g, compared to only 6% and 8%, respectively, for sterile controls. Steady-state chemostat experiments under optimum conditions gave essentially complete removal of wool wax and 90% removal of COD at less than 40 h retention time, and demonstrated that the mechanism of pollutant removal was by bioflocculation rather than aerobic degradation. At 100 L pilot scale, 95% of wool wax and 82% of COD were consistently removed over a period of 116 days of continuous operation at 38 h retention time and 30 degrees C, producing a spadable sludge of 5.7 mL/g. Variable influent concentration or filamentous bacteria did not disrupt this process and foaming was readily controlled using a mechanical foam breaker. After a shutdown period of 15 days the process could be restarted easily, achieving normal performance within one retention time. The successful operation of the pilot reactor suggests this process could be developed to full scale and incorporated into an overall treatment package. 相似文献
22.
There are may factors to consider when denial is encountered in a patient situation. Denial is a simple concept but is complicated by ego-maintaining mechanisms that denial may produce. It is important to evaluate each individual situation in order to identify suitable approaches for the situation. Denial may not be something that the nurse should take away since it can serve an important balancing function between depression and wellness. 相似文献
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Jack Poole 《Computer Communications》1978,1(1):25-32
The retail trade is turning increasingly to computerized systems to provide quickly and accurately the information that it needs to remain profitable.NCR have developed several ranges of computerized point-of-sale equipment for different retail applications. Various systems in use in the food and non-food retail trades are discussed, including those of the Army & Navy group (UK), David Jones (Australia), the Co-Op (UK) and airport duty-free shops.Optical character reading and laser-beam slot scanning will be used to automate further the transaction procedure at the point of sale. 相似文献
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The theory of urethral resistance and the derivation or mural tension have been discussed. A method for the continuous calculation and presentation of these parameters has been described. Urethral resistance and mural tensions are altered by the presence of bladder outflow obstruction and have been shown to return to normality after the obstruction is removed. 相似文献
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28.
Hume ME Harvey RB Stanker LH Droleskey RE Poole TL Zhang HB 《Journal of food protection》2001,64(5):645-651
Arcobacter spp. were isolated from nursing sows and developing pigs on three farms of a farrow-to-finish swine operation and market-age pigs at slaughter. Isolates were identified by polymerase chain reaction and genotypic fragment patterns were examined by pulsed-field gel electrophoresis (PFGE). Incidences of Arcobacter-positive samples increased progressively as the pigs aged, resulting in all of the pens at the end of the growth cycle in the finishing barn containing Arcobacter-positive feces. However, only 10 of 350 cecal samples from slaughtered pigs were positive. There was little similarity between genotypic patterns for Arcobacter collected from the three farms. The level of genotypic variation revealed by PFGE suggested that pigs in this farrow-to-finish operation were colonized by multiple Arcobacter parent genotypes that may have undergone genomic rearrangement, common to members of Campylobacteraceae, during successive passages through the animals. Additionally, the level of genotypic diversity seen among Arcobacter isolates from farms of a single farrow-to-finish swine operation suggests an important role for genotypic phenotyping as a source identification and monitoring tool during outbreaks. 相似文献
29.
Superconducting transition temperatures T
c
are tabulated for about 800 classical compounds classified by their structure type. Some general trends in the data such as the correlation of T
c
values with the number of valence electrons are commented upon. 相似文献
30.
David L. Carthew Graham Buckton Gary E. Parsons Stephen Poole 《The Journal of Adhesion》1997,63(1):89-98
In this study the adsorption of poloxamer block copolymer surfactants to polystyrene latex has been studied at a range of temperatures. It has been noted previously that the adsorption first falls, then rises and falls again as the temperature is increased, due to the existence of a phase transition in aqueous solutions of these surfactants at specific temperatures, which may be a critical micelle temperature. The present study shows that the hydrophobicity of the surface changes in a manner related to the amount of poloxamer adsorbed (i.e. is greatly influenced by the temperature of adsorption in relation to the transition temperature). The coating layer thickness, however, is essentially unchanged by the temperature of adsorption (i.e. not related to the amount adsorbed), but is influenced by the temperature at which the sizing was undertaken. This is due to dehydration of the poly (oxyethylene) with increasing temperature. The data presented here provide a possible explanation for the changes in biological distribution of poloxamer coated particles which occur when they are injected into animals. 相似文献