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31.
French River water (Nova Scotia, Canada) was separated into six different natural organic matter (NOM) fractions, including hydrophobic acids, bases and neutrals and hydrophilic acids, bases and neutrals. The raw water, as well as each of the NOM fractions were analysed for disinfection by-product (DBP) formation potential before and after advanced oxidation with UV/TiO2 to determine the efficacy of this treatment for the removal of DBP precursors. The UV/TiO2 treatment was carried out with a nanostructured thin film (NSTF), coated with TiO2 which is compared with the use of a TiO2 suspension. For the raw river water, removals of total trihalomethane formation potential (TTHMFP) and total haloacetic acid formation potential (THAA9FP) were found to be approximately 20% and 90%, respectively, with 50 mJ/cm2 UV exposure and 1 mg/L TiO2. For the fractionated samples, approximately 75% of both trihalomethane (THM) and haloacetic acid (HAA) precursors were found to be associated with the hydrophobic acid fraction. For this individual fraction the same UV/TiO2 treatments exhibited approximately 20-25% removal of both TTHMFP and THAA9FP, suggesting that the fractionation process may have affected the treatability of HAA precursors or may have altered the results of the oxidation processes.  相似文献   
32.
The performance of carbon-supported, Pd bimetallic catalysts for nitrate reduction has been investigated. Pd–In and Pd–Sn catalysts have been tested for a range of nitrate concentration up to 1000 ppm in acidic and close to neutral pH. Pd–Cu was also studied at pH 5 for reference. Nitrate reduction was inhibited strongly by nitrite and moderately by sulphate. Activated carbon catalysts are shown to display an activity similar to metal oxide supported catalysts.  相似文献   
33.
We investigated the plume structure of a piezo-electric sprayer system, set up to release ethanol in a wind tunnel, using a fast response mini-photoionizaton detector. We recorded the plume structure of four different piezo-sprayer configurations: the sprayer alone; with a 1.6-mm steel mesh shield; with a 3.2-mm steel mesh shield; and with a 5 cm circular upwind baffle. We measured a 12 × 12-mm core at the center of the plume, and both a horizontal and vertical cross-section of the plume, all at 100-, 200-, and 400-mm downwind of the odor source. Significant differences in plume structure were found among all configurations in terms of conditional relative mean concentration, intermittency, ratio of peak concentration to conditional mean concentration, and cross-sectional area of the plume. We then measured the flight responses of the almond moth, Cadra cautella, to odor plumes generated with the sprayer alone, and with the upwind baffle piezo-sprayer configuration, releasing a 13:1 ratio of (9Z,12E)-tetradecadienyl acetate and (Z)-9-tetradecenyl acetate diluted in ethanol at release rates of 1, 10, 100, and 1,000 pg/min. For each configuration, differences in pheromone release rate resulted in significant differences in the proportions of moths performing oriented flight and landing behaviors. Additionally, there were apparent differences in the moths’ behaviors between the two sprayer configurations, although this requires confirmation with further experiments. This study provides evidence that both pheromone concentration and plume structure affect moth orientation behavior and demonstrates that care is needed when setting up experiments that use a piezo-electric release system to ensure the optimal conditions for behavioral observations.  相似文献   
34.
    
In some parts of Europe, stone wall field boundaries pervade agricultural landscapes, yet despite their prominence there has been very little research into field boundary walls anywhere. However, these anthropogenic features within cultural landscapes may offer insights into current debates on ‘novel’ ecosystems because of their artifice, their longevity in the landscape particularly in remote or exposed regions, and their morphology. In a review of the available, published literature in Europe, it was found that no publications exist that examine or illustrate specific ecological characteristics of field boundary stone walls, despite this longevity. Using examples from Ireland, where these structures are locally abundant, this paper aims first to draw attention to the poorly representative literature on this topic, and thus stimulate research that will detail the potential ecological characteristics of these ancient forms of field boundary. It then briefly explores the potential for these walls to be considered as ‘novel’ ecosystems within current debates on the issue.  相似文献   
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A formal procedure for managing software maintenance—from the submission of a work order through the postimplementation review—opens a window of opportunity for the IS manager who sees systems as candidates for reverse engineering, reengineering, and restructuring. This article describes a set of procedures for improving maintenance management.  相似文献   
37.
Postinjury multiple organ failure: a bimodal phenomenon   总被引:1,自引:0,他引:1  
To better define the epidemiology of postinjury multiple organ failure (MOF), we prospectively evaluated 457 high-risk trauma patients who survived more than 48 hours. Overall, 70 (15%) developed MOF. In 27 (39%) patients, the occurrence was early, while in 43 (61%) patients the presentation was delayed. At presentation, early MOF had more cardiac dysfunction, while late MOF had greater hepatic failure. Indices of shock were more critical risk factors for early MOF, while advanced age was more important for late MOF. While early and late MOF had a similar high incidence of major infections, these appeared to be more important in precipitating late MOF. Finally, while mortality is similar, early MOF patients appear to succumb faster. In conclusion, postinjury MOF remains a significant challenge and appears to present in at least two patterns (i.e., early versus late). Better understanding of the relative roles of the dysfunctional inflammation and infections in early MOF versus late MOF may facilitate the development of new strategies for the prevention and treatment of morbid syndrome.  相似文献   
38.
Grading systems are used in many countries to aid in separating oilseeds into marketable groups according to quality. Factors are compared for two types of systems: the fixed grade system used in Canada, the USA and Sweden, and the sliding scale system used in Australia and the EEC (European Economic Community) which is being considered by the International Standards Organization. The relationship between grade, degrading factors and end-use quality is discussed, specifically for Canadian oilseeds. Future use of NIR technology and other rapid nonvisual techniques in systems which now rely on visual assessment is considered. Paper No. 532 from the Grain Research Laboratory.  相似文献   
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Barley is cultivated both in highly productive agricultural systems and also in marginal and subsistence environments. Its distribution is worldwide and is of considerable economic importance for animal feed and alcohol production. The overall importance of barley as a human food is minor but there is much potential for new uses exploiting the health benefits of whole grain and beta-glucans. The barley supply chains are complex and show added value at many stages. Germplasm resources for barley are considerable, with much potential for exploitation of its biodiversity available through the use of recently developed genomic and breeding tools. Consequently, substantial gains in crucial sustainability characteristics should be achievable in the future, together with increased understanding of the physiological basis of many agronomic traits, particularly water and nutrient use efficiency. Barley’s ability to adapt to multiple biotic and abiotic stresses will be crucial to its future exploitation and increased emphasis on these traits in elite germplasm is needed to equip the crop for environmental change. Similarly, resource use efficiency should become a higher priority to ensure the crop’s sustainability in the long-term. Clearly barley is a resilient crop with much potential which can be realised in the future.  相似文献   
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