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排序方式: 共有1136条查询结果,搜索用时 15 毫秒
91.
92.
Removal of the endocrine disrupter nonylphenol and its estrogenic activity in sludge treatment processes 总被引:2,自引:0,他引:2
The estrogenic compound nonylphenol (NP) is frequently found in sludge from sewage treatment works. Hence, when sewage sludge is spread on the land, endocrine-disrupting compounds may get into the soil. The goal of this study was to investigate the extent to which aerobic mesophilic treatment in continuous reactors permits the removal of NP from sludge and how this process may be useful for treating anaerobically stabilised sludge. We also report on the behaviour of NP during the anaerobic treatment of sludge. The reduction in sludge estrogenic activity observed in the different types of treatment, as measured using estrogen-responsive reporter cells lines (MELN bioassay), was compared with NP removal rates. Under anaerobic conditions, no degradation of NP and its estrogenic activity was observed. Indeed, an accumulation of the compound occurred. In contrast, high removal of NP was achieved in aerobic conditions as well as in aerobic Post-treatment of anaerobically pre-digested sludge, with a concomitant reduction of the sludge's estrogenic potency. 相似文献
93.
A significant role for a future nuclear carbon-free energy production is attributed to fast reactors, mostly employing a liquid metal as a coolant. This paper summarizes the efforts that have been undertaken in collaborative projects sponsored by the European Commission in the past 20 years in the fields of liquid-metal heat transfer modeling, fuel assembly and core thermal hydraulics, pool and system thermal hydraulics, and establishment of best practice guidelines and verification, validation, and uncertainty quantification (UQ). The achievements in these fields will be presented along with the prospects on topics which will be studied collaboratively in Europe in the years to come. These prospects include further development of heat transfer models for applied computational fluid dynamics (CFD), further analysis of the consequences of fuel assembly blockages on coolant flow and temperature, analysis of the thermal hydraulic effects in deformed fuel assemblies, extended validation of three-dimensional pool thermal hydraulic CFD models, and further development and validation of multi-scale system thermal hydraulic methods. 相似文献
94.
Belén Díaz Emma Härkönen Jolanta ?wiatowska Vincent Maurice Antoine Seyeux Philippe Marcus Mikko Ritala 《Corrosion Science》2011,(6):2168-2175
ToF-SIMS, XPS, voltammetry and EIS investigation of the anti-corrosion properties of thin (10, 50 and 100 nm) alumina coatings grown by atomic layer deposition at 160 °C on steel is reported. Surface analysis shows a thickness-independent Al2O3 stoichiometry of the coating and trace contamination by the growth precursors. The buried coating/alloy interface has iron oxide formed in ambient air and/or resulting from the growth of spurious traces in the initial stages of deposition. Electrochemical analysis yields an exponential decay of the coating porosity over four orders of magnitude with increasing thickness, achieved by sealing of the more defective first deposited 10 nm. 相似文献
95.
C. Lethien M. Zegaoui P. RousselP. Tilmant N. Rolland P.A. Rolland 《Microelectronic Engineering》2011,88(10):3172-3177
The paper deals with the methodology used to form regular pattern of sputtered thin films LiPON/LiFePO4 material acting respectively as the solid electrolyte and the positive electrode of the lithium ion solid state 3D micro-battery. The micromachining of the silicon periodic nanopillars array (negative electrode of the micro-battery) is also reported. The proposed study clearly demonstrates a breakthrough technology in the field of lithium ion micro-battery as the ecologically friendly LiFePO4 material has never been evaluated as the positive electrode. 相似文献
96.
97.
Antoine Doucet Gabriella Kazai Bodin Dresevic Aleksandar Uzelac Bogdan Radakovic Nikola Todic 《International Journal on Document Analysis and Recognition》2011,14(1):45-52
This paper describes the setup of the Book Structure Extraction competition run at ICDAR 2009. The goal of the competition
was to evaluate and compare automatic techniques for deriving structure information from digitized books, which could then
be used to aid navigation inside the books. More specifically, the task that participants faced was to construct hyperlinked
tables of contents for a collection of 1,000 digitized books. This paper describes the setup of the competition and its challenges.
It introduces and discusses the book collection used in the task, the collaborative construction of the ground truth, the
evaluation measures, and the evaluation results. The paper also introduces a data set to be used freely for research evaluation
purposes. 相似文献
98.
99.
Antoine Legay Andreas Zilian Christian Janssen 《International journal for numerical methods in engineering》2011,86(6):667-687
This contribution discusses extended physical interface models for fluid–structure interaction problems and investigates their phenomenological effects on the behavior of coupled systems by numerical simulation. Besides the various types of friction at the fluid–structure interface the most interesting phenomena are related to effects due to additional interface stiffness and damping. The paper introduces extended models at the fluid–structure interface on the basis of rheological devices (Hooke, Newton, Kelvin, Maxwell, Zener). The interface is decomposed into a Lagrangian layer for the solid‐like part and an Eulerian layer for the fluid‐like part. The mechanical model for fluid–structure interaction is based on the equations of rigid body dynamics for the structural part and the incompressible Navier–Stokes equations for viscous flow. The resulting weighted residual form uses the interface velocity and interface tractions in both layers in addition to the field variables for fluid and structure. The weak formulation of the whole coupled system is discretized using space–time finite elements with a discontinuous Galerkin method for time‐integration leading to a monolithic algebraic system. The deforming fluid domain is taken into account by deformable space–time finite elements and a pseudo‐structure approach for mesh motion. The sensitivity of coupled systems to modification of the interface model and its parameters is investigated by numerical simulation of flow induced vibrations of a spring supported fluid‐immersed cylinder. It is shown that the presented rheological interface model allows to influence flow‐induced vibrations. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
100.
Louis A. Buscarlet Jacques L. Ravenel Antoine Guitton 《Journal of Stored Products Research》1986,22(4):217-225
The aim of this study was to determine whether or not the change of the free amino acid (FAA) contents in irradiated Tribolium confusum male adults could be assigned to a lack of nutrition. The concentration of the amino acid pool (FAA) in Tribolium confusum males irradiated at 63, 315 and 504 Gy changed with time in nearly the same way as in insects deprived of food. This result confirms the inhibitory effect of irradiation on digestive functions. The time-course of FAA changes was dose independent from 63 to 504 Gy. No specific effect on intermediary metabolism was observed. The possibility of using FAA analysis to identify irradiated grains is discussed. 相似文献