• Energy Research
• Closed Access close
• IT close
• AE close

The paper proposes a critical assessment of municipal solid waste gasification today, starting from basic aspects of the process (process types and steps, operating and performance parameters) and arriving to a comparative analysis of the reactors (fixed bed, fluidized bed, entrained bed, vertical shaft, moving grate furnace, rotary kiln, plasma reactor) as well as of the possible plant configurations (heat gasifier and power gasifier) and the environmental performances of the main commercially available gasifiers for municipal solid wastes. The analysis indicates that gasification is a technically viable option for the solid waste conversion, including residual waste from separate collection of municipal solid waste. It is able to meet existing emission limits and can have a remarkable effect on reduction of landfill disposal option.

AbstractThe efficacy of thyroid (FNAB) processed by liquid‐based cytology (LBC) in Hashimoto's Thyroiditis (HT) in two reference periods, is evaluated. The morphologic features of 820 cases with both methods and the cyto‐histological comparison are analyzed. The diagnosis of hyperplastic nodules (HN) in HT, its mimickers especially in presence of oxyphilic cells and the role of immunocytochemistry (IHC) are studied.150 cases of HT processed by conventional smear (CS) in 1996–98 and 670 with LBC in 2005–2007,were included. The majority of FNAB were carried out under USguidance and fixed with ethyl alcohol for the CS. LBC material was rinsed in the Cytolit solution, processed according to the manufacturer's recommendations. Among the 150 CS, 83 were HT while 67 were HN in HT; in the second triennium 245 LBC were HT and 425 were HN in HT. In the first period a follow‐up (including a second FNA or surgery) was done in 92 cases, in the second period in 116.In the surgical group 97.1% in the first period were benign (all HT and 34/36 HN) and 2.8% malignant(all HN). In 2005–2007, 94% were benign (15 HT and 45/49 HN) and 6%malignant. Thirty HN from the second triennium had ICC for HBME‐1 and Galectin‐3 resulting negative in 93.5%. Among these cases, 10 had a benign histology and a concordant negative ICC.LBC can be used as a valid method for HT, especially for the possible application of ICC to HN, and it allows a correct preoperative selection of lesions Diagn. Cytopathol. 2011; © 2011 Wiley‐Liss, Inc.

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.

It's not only the carbon in the trees Forest loss affects climate not just because of the impacts it has on the carbon cycle, but also because of how it affects the fluxes of energy and water between the land and the atmosphere. Evaluating global impact is complicated because deforestation can produce different results in different climate zones, making it hard to determine large-scale trends rather than more local ones. Alkama and Cescatti conducted a global assessment of the biophysical effects of forest cover change. Forest loss amplifies diurnal temperature variations, increases mean and maximum air temperatures, and causes a significant amount of warming when compared to CO 2 emission from land-use change. Science , this issue p. 600

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.

For many decades, state estimation (SE) has been a critical technology for energy management systems utilized by power system operators. Over time, it has become a mature technology that provides an accurate representation of system state under fairly stable and well understood system operation. The integration of variable energy resources (VERs) such as wind and solar generation, however, introduces new fast frequency dynamics and uncertainties into the system. Furthermore, such renewable energy is often integrated into the distribution system thus requiring real-time monitoring all the way to the periphery of the power grid topology and not just the (central) transmission system. The conventional solution is two fold: solve the SE problem (1) at a faster rate in accordance with the newly added VER dynamics and (2) for the entire power grid topology including the transmission and distribution systems. Such an approach results in exponentially growing problem sets which need to be solver at faster rates. This work seeks to address these two simultaneous requirements and builds upon two recent SE methods which incorporate event-triggering such that the state estimator is only called in the case of considerable novelty in the evolution of the system state. The first method incorporates only event-triggering while the second adds the concept of tracking. Both SE methods are demonstrated on the standard IEEE 14-bus system and the results are observed for a specific bus for two difference scenarios: (1) a spike in the wind power injection and (2) ramp events with higher variability. Relative to traditional state estimation, the numerical case studies showed that the proposed methods can result in computational time reductions of 90%. These results were supported by a theoretical discussion of the computational complexity of three SE techniques. The work concludes that the proposed SE techniques demonstrate practical improvements to the computational complexity of classical state estimation. In such a way, state estimation can continue to support the necessary control actions to mitigate the imbalances resulting from the uncertainties in renewables.

In recent years, deregulation in the power generation market worldwide combined with significant variation in fuel prices and a need for flexibility in terms of power augmentation specially during periods of high electricity demand (summer months or noon to 6 PM) has forced electric utilities, cogenerators and independent power producers to explore new power generation enhancement technologies. In the last 5–10 years, inlet fogging approach has shown more promising results to recover lost power output due to increased ambient temperature compared to the other available power enhancement techniques. This paper presents the first systematic study on the effects of both inlet evaporative and overspray fogging on a wide range of combined cycle power plants utilizing gas turbines available from the major gas turbine manufacturers worldwide. A brief discussion on the thermodynamic considerations of inlet and overspray fogging including the effect of droplet dimension is also presented. Based on the analyzed systems, the results show that high pressure inlet fogging influences performance of a combined cycle power plant using an aero-derivative gas turbine differently than with an advanced technology or a traditional gas turbine. Possible reasons for the observed differences are discussed.