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921.
T. Wambecq A. Fenu K. De Gussem G. Parmentier G. De Gueldre B. Van De Steene 《Water and Environment Journal》2013,27(2):247-252
This study quantifies the impact of the oxidation ditch horizontal water velocity on the energy consumption of a full‐scale wastewater treatment plant (WWTP). A WWTP was modelled by means of the ASM2d platform, showing very good correlation with reference operational data. As to reduce the energy requirements of the plant while guarantying the same nutrient removal performance, two approaches were used. A classical aeration control optimization, yielding a 4% energy reduction, was compared with an increase of the oxidation ditch propelling power. The horizontal water velocity in the oxidation ditches was estimated at only 0.15 m/s. By increasing the horizontal water velocity to 0.3 m/s, an 8% energy reduction could be achieved. Moreover, a synergistic effect for classic control optimization and oxidation ditch water velocity optimization resulted in a 14% energy reduction. Energy spent in propelling power counteracts the aeration energy gain derived by an increase in the oxidation ditch horizontal velocity. An optimum in the water velocity was quantified at 0.3 m/s, comparably with its design value. 相似文献
922.
923.
R. H. Charlier C. P. De Meyer 《The International journal of environmental studies》2013,70(4):249-265
Processing municipal and industrial wastes on land and particularly near inhabited centra has met with increased opposition. An apparent remedy to the problem is the establishment of such facilities offshore, hence various projects to build them on artificial islands. The paper examines a concrete proposal to locate such an island offshore from the Belgian Coast. Oceanographic and environmental aspects of the site are discussed, construction methods reviewed, erosion and corrosion effects looked at. The possibility of utilizing ocean power to provide the necessary operation energy is likewise considered. 相似文献
924.
N. De la Cruz L. Esquius D. Grandjean A. Magnet A. Tungler L.F. de Alencastro C. Pulgarín 《Water research》2013
This study focuses on the removal of 22 selected micropollutants in an effluent from a municipal wastewater treatment plant (MWTP) at pilot scale. A reactor of 37 L with five low pressure mercury lamps emitting at 254 nm (UV254) was used. The 22 micropollutants include 15 pharmaceuticals, 2 X-Ray contrast medias, 1 corrosion inhibitor and 4 biocides/pesticides. Five of these 22 compounds were used as indicative substances as proposed by the Swiss Federal Office for the Environment (FOEN) (carbamazepine, diclofenac, sulfamethoxazole, benzotriazole and mecoprop). 相似文献
925.
926.
Christopher D. Sinigalliano Jared S. Ervin Laurie C. Van De Werfhorst Brian D. Badgley Elisenda Ballesté Jakob Bartkowiak Alexandria B. Boehm Muruleedhara Byappanahalli Kelly D. Goodwin Michèle Gourmelon John Griffith Patricia A. Holden Jenny Jay Blythe Layton Cheonghoon Lee Jiyoung Lee Wim G. Meijer Rachel Noble Meredith Raith Hodon Ryu Michael J. Sadowsky Alexander Schriewer Dan Wang David Wanless Richard Whitman Stefan Wuertz Jorge W. Santo Domingo 《Water research》2013
Here we report results from a multi-laboratory (n = 11) evaluation of four different PCR methods targeting the 16S rRNA gene of Catellicoccus marimammalium originally developed to detect gull fecal contamination in coastal environments. The methods included a conventional end-point PCR method, a SYBR® Green qPCR method, and two TaqMan® qPCR methods. Different techniques for data normalization and analysis were tested. Data analysis methods had a pronounced impact on assay sensitivity and specificity calculations. Across-laboratory standardization of metrics including the lower limit of quantification (LLOQ), target detected but not quantifiable (DNQ), and target not detected (ND) significantly improved results compared to results submitted by individual laboratories prior to definition standardization. The unit of measure used for data normalization also had a pronounced effect on measured assay performance. Data normalization to DNA mass improved quantitative method performance as compared to enterococcus normalization. The MST methods tested here were originally designed for gulls but were found in this study to also detect feces from other birds, particularly feces composited from pigeons. Sequencing efforts showed that some pigeon feces from California contained sequences similar to C. marimammalium found in gull feces. These data suggest that the prevalence, geographic scope, and ecology of C. marimammalium in host birds other than gulls require further investigation. This study represents an important first step in the multi-laboratory assessment of these methods and highlights the need to broaden and standardize additional evaluations, including environmentally relevant target concentrations in ambient waters from diverse geographic regions. 相似文献
927.
The objective of this study is to show that the core competence approach has validity when applied to construction. The focus is on the analysis of the fit between market strategies of firms in the building industry and their core capabilities. Certain strategies require specific core capabilities and key external and internal conditions supporting these capabilities. The resource-based approach focuses on the conditions in a firm, the internal capabilities, and supports a core capability that is demanded. The network literature will be related to external conditions that support a core capability of a firm active in a certain market. In a multiple case study, firms are analysed that are involved in different stages of the building process. The case studies demonstrate firms with consistent patterns of market strategies, core capabilities, and supporting internal and external conditions. The specific core capability of the firm under investigation determines the types of external and internal conditions that are critical. 相似文献
928.
929.
Simon De Nys-Ketels Laurence Heindryckx Johan Lagae Luce Beeckmans 《Planning Perspectives》2013,28(5):757-778
ABSTRACTThroughout the 1950s, the Belgian colonial government constructed a vast network of hospital infrastructure as part of its Ten-Year Plan, a colony-wide socio-economic scheme emblematic for the era of ‘welfare colonialism.’ This network played a key role in Belgian colonialism, by providing healthcare, but also by boosting labour productivity, facilitating state presence and control, and by advertising Congo as a medical model-colony. In this article, we unpack the extensive administrative apparatus that was necessary to buttress this ambitious building programme, and we highlight type-plans as crucial government tools to construct such a vast network of healthcare infrastructure. At first glance, the use of type-plans confirms classic characterizations of the Belgian colonial government as an omnipotent and technocratic state apparatus that implemented large, top-down government plans through authoritative methods, often discarding local realities. However, tracing hospital construction on the ground reveals that type-plans did not function as immutable models, but rather as modular blueprints that allowed local administrations to adapt hospitals to local needs and contingencies. As such, our article illustrates how, facilitated by surprisingly flexible type-plans, everyday colonial policymaking in Belgian Congo was, contrary to the still dominant discourse, deeply reliant on the agency and aptitude of local officials. 相似文献
930.