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Efficiency of energy resource use is a key factor for a sustainable energy future. By matching the exergy levels of supply and demand, Energy Quality Management (EQM) of building energy supply systems may achieve more efficient use of energy resources. Beyond this, environmental impact of energy supply systems is another essential issue. This work addresses the influence of EQM on CO 2 emissions in the operation optimization of a Distributed Energy System (DES). A multi-objective linear programming problem is formulated to reduce energy costs and increase the overall exergy efficiency. Total CO 2 emissions are evaluated for the optimized operation strategies of the DES. The operators of the DES can choose the operation strategy from the Pareto front, based on their priorities and also aware of effects on CO 2 emissions. Results demonstrate more efficient use of energy resources and reduction in CO 2 emissions through EQM, as compared with conventional energy supply systems.

Abstract Sodium-promoted vanadium oxide catalysts supported on MCM-41 and TiO 2 (anatase) were investigated for the partial oxidation of ethanol to acetaldehyde. The catalysts were prepared by incipient wetness impregnation with a vanadium oxide content of 6 wt.%. The experimental characterization was performed by X-ray diffraction (XRD), N 2 adsorption, temperature-programmed reduction (TPR), and diffuse reflectance UV–vis. Temperature-programmed oxidation (TPO) was also used to identify carbon deposits on the spent catalysts. The presence of sodium plays a strong role in the dispersion and reducibility of the vanadium species as detected by TPR analysis and optical absorption spectroscopy. While sodium addition increases the dispersion of the VO x species, its presence also decreases their reducibility. Additionally, TPO of the spent catalysts revealed that an increase in the Na loading decreases the carbon deposition during reaction. In the case of the catalysts supported on MCM-41, these modifications were mirrored by a change in the activity and selectivity to acetaldehyde. Additionally, on the VO x /TiO 2 catalysts the catalytic activity decreased with increasing sodium content in the catalyst . A model in which sodium affects dispersion, reducibility and also acidity of the supported-vanadia species is proposed to explain all these observations.

We report measurement of initial G2-chromatid breaks in normal human fibroblasts exposed to various types of high-LET particles. Exponentially growing AG 1522 cells were exposed to gamma rays or heavy ions. Chromosomes were prematurely condensed by calyculin A. Chromatid-type breaks and isochromatid-type breaks were scored separately. The dose response curves for the induction of total chromatid breaks (chromatid-type + isochromatid-type) and chromatid-type breaks were linear for each type of radiation. However, dose response curves for the induction of isochromatid-type breaks were linear for high-LET radiations and linear-quadratic for gamma rays. Relative biological effectiveness (RBE), calculated from total breaks, showed a LET dependent tendency with a peak at 55 keV/micrometer silicon (2.7) or 80 keV/micrometer carbon (2.7) and then decreased with LET (1.5 at 440 keV/micrometer). RBE for chromatid-type break peaked at 55 keV/micrometer (2.4) then decreased rapidly with LET. The RBE of 440 keV/micrometer iron particles was 0.7. The RBE calculated from induction of isochromatid-type breaks was much higher for high-LET radiations. It is concluded that the increased production of isochromatid-type breaks, induced by the densely ionizing track structure, is a signature of high-LET radiation exposure.

We present results on optical, structural and electrical properties of a-Si1-xCx:H films deposited by plasma enhanced chemical vapor deposition in the low power regime, with C fraction from 0 to 0.28. The absorption coefficient has been obtained in the region 0.73-4.5 eV by means of ellipsometry, reflectance-transmittance and photothermal deflection spectroscopy. The addition of carbon in the alloy increases the disorder and the density of defects: samples deposited with high carbon content have poorer optoelectronic properties. Two conduction regimes are observed: extended state conduction and hopping conduction in the conduction band tail. A visible PL peak that widens and shifts to higher energies as the carbon content increases has been observed. (c) 2006 Elsevier B.V. All rights reserved.

Confluent human fibroblast cells were exposed to 6 Gy gamma-rays or 200 MeV/nucleon Fe ions at 0.7 or 3 Gy. The cells were allowed to repair for 24 hours after exposure and chromosomes were collected using a premature chromosome condensation technique with calyculin-A. Chromosome aberrations were analyzed using the multicolor FISH (mFISH) technique that allows identification of both complex and truly incomplete exchanges. Results showed that both doses of the Fe ions produced higher ratios of complex to simple exchanges and lower ratio of complete to incomplete exchanges than the 6 Gy gamma-exposure. The ratios of aberration yields were similar for the two doses of Fe ions. After 0.7 Gy of Fe ions, most complex aberrations were found to involve three or four chromosomes, indicating this is the maximum number of chromosome domains traversed by a single Fe ion track.

To compare magnetic resonance (MR) imaging and multidetector computed tomography (MDCT) for the assessment of myocardial infarction (MI) after alcohol septal ablation (ASA).Ten patients (mean age, 60 years ± 16) were examined with both MDCT and 1.5-T MR imaging performed 10 minutes after injection, within 3 days after ASA. Half of them had a temporary pacemaker (PM) during MDCT examination. Global image quality (IQ) and localization of MI were noticed on both MDCT and MR images. Volumes of MI, contrast-to-noise ratios (CNR) and signal-to-noise ratios (SNR) were also calculated. ASA effectiveness was evaluated by echocardiography immediately and 3 months after procedure.Global IQ was considered adequate for both procedures. In 8 patients, MI reached the basal part of the septum on both MDCT and MR images. The 2 remaining patients exhibited sparing of the basal septum on MDCT and MR images. Volumes of MI were within the same range with the 2 techniques (MDCT: 22.1 ± 8.8 mL; MR imaging: 23.8 ± 9.4 mL) and correlated well each other (R(2)=0.85, p<0.002). The 2 patients with sparing of the basal interventricular septum had persistent gradient on echocardiography 3 months after ASA, suggesting failure of the procedure. The volumes of MI didn't correlate with the reduction of pressure gradient on echocardiography 3 months after ASA (R(2)=0.02, p<0.05).Evaluation of post ASA MI is feasible with MDCT by comparison with MR imaging. MDCT might serve as an alternative imaging method in case of PM implantation.

Reducing ecological impact is a major challenge for today’s industry, particularly the rail industry, which is one of the most energy-intensive industries. Indeed, this industry faces two paradoxical needs: on the first hand, it must decrease its energy consumption, meeting both an environmental goal and a financial objective, and on the other hand, it must not only maintain but increase the circulation of train, thus allowing a larger part of the population to use the most ecological means of land transport. Reducing consumption requires a prediction model. The formalization of this model is complex, particularly when driver control is taken into account. The complexity of the model must be chosen carefully. The SNCF has a very sophisticated model with a large number of parameters that need to be evaluated. In this work, we consider a train dynamics model simplified to a non-linear differential longitudinal dynamics equation coupled to a power balance [1]. In this model it is possible to distinguish two types of inputs:the model parameters which will be calibrated and the environment variables (wind, driver’s control, etc.) which will change from one journey to another. In order to calibrate the model, we rely on a priori knowledge from SNCF experts who provide information on the values of the model parameters. We also have a set of measurements (time, speed, power consumption, control) taken on the same train, for different journeys on different tracks. The used methodology is Bayesian calibration [2], which makes it possible to use the two types of information available to us while injecting model errors to take account of our imperfect knowledge of the system. These errors are parameterized by hyper-parameters that should also be calibrated. It is then necessary to formalize the experts’ knowledge mathematically in order to create our prior distributions, and then to write a likelihood function that will allow us to take into account both the measurements and the model errors. Another difficulty is the lack of knowledge about driver control as the control isn’t measured. The control linked to each measurement must be determined and appears in our problem asfunctional hyper-parameters.REFERENCES:[1] Julien Nespoulous, Christian Soize, Christine Funfschilling, and Guillaume Perrin. Optimisation of train speed to limit energy consumption. Vehicle System Dynamics, 60(10):3540–3557, October 2022.[2] Christian Soize. Uncertainty quantification: An accelerated course with advanced applications in computational engineering. Springer International Publishing, Cham, Switzerland, 2018.

La place centrale des savoirs dans les choix d’action publique est remise en cause par la « mise en risque » de phénomènes climatiques et hydrologiques qui s’avèrent imprévisibles et irréversibles. C’est le cas du recul du trait de côte des falaises en Picardie. Longtemps basé sur une approche scientifique et technique dite de « recul moyen », l’État doit recomposer ses moyens d’action face à l’occurrence de risques extrêmes et brusques. Or, il ne s’agit pas seulement de changer de modalités dans l’approche technique, ni de promouvoir de nouveaux outils de prévention pour construire des stratégies de recomposition territoriale des littoraux. Le cas de l’effondrement de la falaise d’Ault illustre le besoin urgent d’intégrer dans l’action publique une pluralité de connaissances des effets du changement climatique, tant en termes de savoirs qui peuvent être alternatifs et scientifiques que de connaissances tirées de l’expérience sensible, personnelle ou esthétique. The central place of knowledge in public policy choices is being challenged by climate and hydrological phenomena that turn out to be unpredictable and irreversible. This is the case with the retreat of the coastline of the cliffs in Picardy. For a long time based on a scientific and technical approach known as “average retreat”, the national government now has to reconstitute its methods of action in the face of extreme and sudden risks. But it’s not just a question of changing the technical approach, or promoting new prevention tools to build strategies for reorganising coastal areas. The case of the collapse of the cliffs at Ault illustrates the urgent need to integrate multiple forms of knowledge about the effects of climate change into public action, both in terms of alternative and scientific knowledge and in terms of knowledge rooted in sensitive, personal, or aesthetic experience. International audience