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The main objective of this paper is to illustrate the current state of the art of the newborn smart gas grid concept. We provide a detailed discussion of the envisaged features of the smart gas grid, giving attention to both the related academic literature and to the ongoing world-wide projects. In doing so, we also discuss the potentialities of rethinking the smart grid paradigm from the perspective of a whole energy system, that both encompasses the electrical and the gas grid, and identify some critical key aspects that must be handled while developing the new smart energy paradigm.

We report the effect of ethanol on monooxygenase activities in primary hamster hepatocyte cultures maintained on collagen-coated dishes. The addition of 50mM ethanol to cell cultures both from control and ethanol pretreated animals almost completely maintained, at least for 72hr, the P4502E1-dependent aniline hydroxylase (AnH) activity and the 2E1 immunodetectable apoprotein content at the levels of the corresponding 4-hr plated hepatocytes. On the contrary, other P450-dependent monooxygenase activities, as assayed by testosterone hydroxylases, kept decreasing falling-after 72hr of culture-to the levels of the 4-hr plated hepatocytes. In both cases, in the absence of ethanol, a rapid decline of AnH activities and 2E1 apoprotein contents were also observed, attaining undetectable levels at 72hr. The hybridizable 2E1 mRNA also rapidly declined in both cultures, but such decline was not significantly altered by the presence of 50mM ethanol in the culture medium. Furthermore, we show that P4502E1 in the liver possesses a rapid degradation phase with a half-life of about 6hr. Thus, in the hamster, P4502E1 appears regulated at post-translational level, as in rat, probably by a protein stabilization mechanism.

Abstract Hydropower plants are one of the most convenient option for power generation, as they generate energy exploiting a renewable source, they have relatively low operating and maintenance costs, and they may be used to provide ancillary services, exploiting the large reservoirs of available water. The recent advances in Information and Communication Technologies (ICT) and in machine learning methodologies are seen as fundamental enablers to upgrade and modernize the current operation of most hydropower plants, in terms of condition monitoring, early diagnostics and eventually predictive maintenance. While very few works, or running technologies, have been documented so far for the hydro case, in this paper we propose a novel Key Performance Indicator (KPI) that we have recently developed and tested on operating hydropower plants. In particular, we show that after more than one year of operation it has been able to identify several faults, and to support the operation and maintenance tasks of plant operators. Also, we show that the proposed KPI outperforms conventional multivariable process control charts, like the Hotelling t 2 index.

The devolatilization of solid fuels is of crucial importance for all thermo­chemical processes and is the basic step in gasification and combustion models. Here a structural model is developed to provide an Advanced tool for Biomass and Coal Devolatilization (ABCD model), even in blend. The main features are founded on the original approach of the CPD (Chemical Percolation Devolatilization) model by Fletcher [1]. The ABCD model extends the approach also to biomass fuels. Further improvements of the ABCD model are: (i) a population balance between n­mers in liquid metaplast; (ii) elemental balance closure with the speciation of light gases, hetero­species and tar composition; (iii) introduction of secondary reactions of tar­cracking and crosslinking. The ABCD model results agree with a selection of experimental data (from homemade and literature works) on different biomasses. The results reported in this paper encouraged IFRF in continuing the experimental campaign for the validation of the model by extending the Solid Fuel DataBase SFDB. The inclusion of ABCD in comprehensive codes (e.g., Reactor Network Analysis, RNA [2]) and process models is valuable because it gives detailed distribution of pyrolysis products in a wide range of conditions with a low computational cost. Proceedings of the 18th European Biomass Conference and Exhibition, 3-7 May 2010, Lyon, France, pp. 923-930

Abstract A new methodology for estimation of the key characteristics of commercial scale Vanadium Redox Flow Battery (VRFB) at different operating conditions is proposed. The method is based on a set of simplified correlations that allow estimating VRFB rated power, capacity and operation time directly from the geometry of stack and tank without detailed numerical simulation of the battery. The study is focused on investigation of a kilo-watt class VRFB system (5 kW/15kWh) considering a wide range of current densities (40–100 mA cm−2). The proposed simplified approach is validated considering the most representative cases of battery operation strategies related to slow and fast modes. It demonstrated high accuracy for the estimation of rated power and operation time (average error below 3%) as well as stored energy (average error below 6%) compare to results of detailed numerical simulation. As a result, the proposed methodology can be used as a simple tool for development of proper battery usage protocol (a schedule for battery usage), which could allow avoiding over/underestimation of committed battery energy and power during battery operation. In addition, the obtained results can be also used in order to improve the accuracy of techno-economic studies determining the most economically attractive cases for application of VRFB systems.

AbstractTwenty‐five patients with solitary autonomous thyroid nodules (15 nontoxic, 10 toxic) received percutaneous ethanol injection treatment (PEIT) under sonographic guidance in 4–7 sessions (1–2 weekly). To test different doses, smaller nodules (volume <15 mL) were given 0.75–2.8 mL ethanol/mL nodular tissue while larger nodules received 0.5–1 mL/mL. Except for 1 patient who developed hyperpyrexia, no relevant adverse effects were observed. A slight, asymptomatic increase in serum thyroid hormone levels was observed in both groups during the treatment. Three months after treatment, a biochemical and clinical remission of hyperthyroidism was observed in 8 of 10 patients with toxic nodules. A significant increase of TSH level was seen in both groups (p<0.01). Significant shrinkage of volume (p<0.001) as well as structural alternations of nodules were consistently recorded at sonography. A linear relationship (r=0.98;p<0.0001) between pretreatment volume and volume reduction was found both for large and small nodules, thus suggesting that even limited ethanol doses may be therapeutically effective. A recovery of extranodular parenchyma activity at scintiscan occurred in 16 (64%) of 25 patients. These data confirm that PEIT is effective in obtaining functional ablation and in inducing remission of hyperthyroidism. Adverse effects are infrequent. In spite of the small patient sample, a 0.5–1 mL ethanol dose per each mL of tissue appears as effective as larger doses and seems appropriate for treatment.

During the starting up period of a centrifugal pump the rotational speed is accelerated rapidly from standstill to its final speed and then established at the rated speed. While flow rate and total dynamic pressure rise are boosted accordingly. In the point of view of a theoretical treatment, pump start-up offers difficulty because both rotational speed and flow rate are variable. A far more difficulty is the linearization of the pump speed which is fundamentally impossible. Since a change in speed of the pump is one of transients cause leading to variation in the pressure and discharge. In order to predict the behaviour of the pump during start-up transient condition a mathematical model is developed. The model is based on a working practical approximation in that the total start-up time is reduced by one third. The influence of the two most important parameters, kinetic energy in the piping system and kinetic energy of the pump, is taken into account in the form of a ratio called hereafter an effective energy ratio. Preliminary test of the model was made on the existing piping systems related to nuclear reactors. As a case of study the safety of the Tehran Research Reactor (TRR) primary piping system, an open pool MTR-type research reactor, is considered. It is demonstrated that, by comparing the curves resulted from the numerical solution of the model in which design data of the TRR are used with the experimental characteristics curves of the TRR, the possibility of primary coolant pump turbining is exceptional.

In this work the activity performed at the DICI (Dipartimento di Ingegneria Civile e Industriale) of the Pisa University in collaboration with the ENEA Brasimone Research Centre is presented. In particular the document deals with the application of an in-house developed coupling methodology between a modified version of RELAP5/Mod3.3 and Fluent commercial CFD code, to the NACIE (Natural Circulation Experiment) LBE experimental loop (built and located at the ENEA Brasimone research centre). The first part of the document treats the description of the NACIE loop type facility, while in the second part, the developed coupling tool is presented and the obtained numerical results are compared to stand alone RELAP5 results and to data obtained from the NACIE experimental campaign. The experimental tests are performed varying the argon flow rate and the electric power supplied to the heater and both natural and assisted circulation tests are investigated. The numerical model set-up is based on a two-way explicit coupling scheme and 2D and 3D geometrical domain were investigated. Comparative analyses among numerical and experimental results showed good agreement, giving positive feedback on the feasibility and capability of the developed coupling methodology.