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41.
BACKGROUND: The performance of a pilot membrane bioreactor system (MBR) was tested for the treatment of municipal wastewater, with emphasis on the capability for removal of selected pharmaceuticals RESULTS: The MBR showed excellent performance with regards to conventional pollutants. However, the removal of specific pharmaceuticals was not as high. Carbamazepine and 17 α‐ethinyl estradiol showed the lowest removal, with mean removal rates of around 20%. Clofibric acid showed the highest removal 70%, while for 17β‐estradiol the mean removal was 40%. In order to distinguish between the two basic mechanisms of removal, adsorption on biomass and biodegradation, adsorption studies on inactivated biomass were performed and mass balances were written for the four pharmaceuticals. The immediate removal observed for the three compounds during short hydraulic retention times may have been primarily due to adsorption. CONCLUSIONS: The removal of carbamazepine, 17β‐estradiol and 17α‐ethynil estradiol, as well as half of the removal of chlofibric acid could be attributed to direct adsorption on biomass within the hydraulic residence time of the reactor. Copyright © 2011 Society of Chemical Industry  相似文献   
42.
Self-help books for psychological disorders have become increasingly popular, yet there is surprisingly little research on their scientific status or overall utility. The authors identified 50 top-selling self-help books for anxiety, depressive, and trauma-related disorders. Using a scale derived from the literature on bibliotherapy, expert psychologists rated each book on overall usefulness, grounding in psychological science, the extent to which it offers reasonable expectations, the extent to which it offers specific guidance for implementing the self-help techniques and for monitoring treatment progress, and whether it offers potentially harmful advice. The results revealed strong intercorrelations among the scales, such that books scoring high along one dimension tended to score high along others. There was wide variability in the overall quality of the books, but several factors emerged as predictors of book quality. The most highly rated books tended to be those having a cognitive behavioral perspective, those written by mental health professionals, those written by authors holding a doctoral degree, and those focusing on specific problems. Implications of the findings, including specific recommendations for authors and consumers of self-help books, are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
43.
A Small‐scale Wort rapid Filtration Test (SWIFT) that predicts beer filtration efficiency has been developed. The test is simple, cost effective and correlates with existing beer filtration tests such as beer Vmax membrane (Esser test) and diatomaceous earth (Walton filter) tests. SWIFT has an advantage over existing beer filtration tests as it can be easily incorporated into barley quality laboratories utilising excess wort from extract analyses, thus negating the need for additional sample preparation or to ferment and age beer. Furthermore, the test does not rely on expensive equipment or specially trained laboratory technicians. SWIFT, which may also be used to evaluate degassed beer, is a syringe test that utilises a 13 mm diameter 0.45 μm membrane and is negatively influenced by wort viscosity (P<0.05). It is envisaged that SWIFT may be applied by barley breeding programs for the evaluation of progeny lines to provide a better prediction of beer filtration performance than total wort β‐glucan measurements. In addition, maltsters and brewers could use SWIFT to assess malt samples, and provide early warning of potential beer filtration problems during the brewing process.  相似文献   
44.
Biomass cofiring at Seward Station   总被引:3,自引:0,他引:3  
Sithe Energies, under a cooperative agreement with EPRI, the US Department of Energy, the Biomass Interest Group (BIG) and the Upgraded Coal Interest Group (UCIG), has developed a demonstration of cofiring biomass with pulverized coal at the Seward Generating Station on Boiler #12. This demonstration, constructed and tested by Foster Wheeler Development Corporation (FWDC) included construction of a facility to receive, screen, store and transport sawdust into a front-fired pulverized coal boiler. This facility has several distinctive features including the sawdust receiving system, the silo storage for processed biomass, and the injection system using the centerpipe of the coal burners. The biomass is prepared separately and transported separately from the coal. The wood waste is then injected into the center of the coal flame and burned there for optimum biofuel performance.

This demonstration, involving an extended period of cofiring testing, is based upon successful parametric tests conducted in December, 1996 and July, 1997. These tests documented the impact of cofiring, in the short term, on capacity, efficiency and emissions. Those results are now being evaluated over a long-term period. Additionally, operational and maintenance issues are being addressed with this demonstration and modifications have been made to improve the handling of the fuel. This paper describes the cofiring system, and reviews progress to date with the combustion tests.  相似文献   

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Amphiphilic TiO2 nanotube arrays (TiO2 NTs) were fabricated through electrochemical oxidation of Ti in solution containing H3PO4 and NaF. Scanning electron microscopic analysis shows that the as-prepared TiO2 NTs have an average pore diameter of 100 nm and a wall thickness of 15 nm. The electrochemical oxidation of Ti can be divided into four stages. In the first stage, when the potential is very low, oxygen formation and Ti dissolution are the major reactions. The second stage corresponds to a slightly higher potential, but less than 2.5 V. In this stage, the formation of TiO2 film occurs. When the potential is increased to the even higher range from 2.5 V to 6 V, the TiO2 film dissolves and nanoporous surface structure is generated. This is the third stage. Further increase of the potential enters stage four. The high potentials cause the self-organization of the nanostructure and allow the formation of well-aligned TiO2 NTs. We also found that the change in surface condition of Ti by annealing heat treatment affects the film dissolution kinetics. As compared with TiO2 thin film, the TiO2 NTs show higher photocatalytic activity on decomposing Rhodamine B. The surface of the TiO2 NTs can be wetted by both water and oil. Such an amphiphilic property comes from the capillary effect of the nanochannel structure of the TiO2 NTs. Because of the amphiphilic property and the photocatalytic activity, we conclude that the TiO2 NTs have the capability of self-cleaning.  相似文献   
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48.
Domain-specific systems are hypothetically specialized with respect to the outputs they compute and the inputs they allow (Fodor, 1983). Here, we examine whether these 2 conditions for specialization are dissociable. An initial experiment suggests that English speakers could extend a putatively universal phonological restriction to inputs identified as nonspeech. A subsequent comparison of English and Russian participants indicates that the processing of nonspeech inputs is modulated by linguistic experience. Striking, qualitative differences between English and Russian participants suggest that they rely on linguistic principles, both universal and language-particular, rather than generic auditory processing strategies. Thus, the computation of idiosyncratic linguistic outputs is apparently not restricted to speech inputs. This conclusion presents various challenges to both domain-specific and domain-general accounts of cognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
49.
This investigation identifies that Mauribrew Lager 497 strain of dried yeast can be used as a standard strain for the determination of malt apparent attenuation limit (AAL). It provides ferment‐ability results for malt quality evaluation laboratories that are comparable to fresh brewery yeast. It was found that the optimal pitching rate in Congress wort (EBC Analytica, 1998, method 4.5.1), was 1 g per 200 mL, pitched at 25°C and fermented for 24 h at 20°C with agitation to complete attenuation. Preliminary trials also indicated that the Mauribrew Lager 497 dry yeast may be useful to brewers for determining the wort batch attenuation characteristics by the limit gravity test. In this case a pitching temperature of 35°C was found to be optimal with all other conditions as above. For the purpose of malt quality evaluation and brewery quality control the advantages of using a standard dry yeast strain include ease and convenience of use, consistency of quality, and uniformity between laboratories when they are located in separate geographic regions.  相似文献   
50.
Although the Internet may be beneficial to clinical practice, its potential for misuse cannot be overlooked. The current probe identified Internet Web sites that contained information that violated the test security of psychological assessment instruments. Five individuals, using multiple search engines, conducted Internet searches to evaluate samples of Web sites. Sites were classified into 1 of 3 levels according to the degree of threat they posed to test security. A small number (2-5%) appeared to be a direct threat to test security. The findings are discussed and recommendations for promoting more ethical use of the Internet are made. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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