A Decision Tool for Wood Waste Valorization

Wood is an increasingly demanded biomaterial used in many fields: construction, materials, furniture, packaging, and energy. New consumption tendency indicates a major production of wood waste that is a starter for many processes. In Europe, about 54 % of wood waste is incinerated, while 46 % is recycled. In Italy, almost 95 % of wood waste is used to produce chipboard and particleboard. There are many other processes available to improve wood recycling; however, it is important to identify the best treatment way depending on the source matrix. Wood waste is a heterogeneous material that contains contaminating materials, pollutants, and additives. Hence, wood waste management depends on material composition analysis. In fact, it gives significant suggestions regarding how to manage the waste. From this point of view, a decision tool (DT) regarding wood waste destiny hinging on chemical composition is proposed. In particular, the DT gives rapid recommendation based on the chemical results. The most relevant elements considered are cellulose, lignin and hemicellulose content. In addition, pollutants, additives, and other contaminants are crucial to find the best pathway. Some available technologies make it possible to use wood waste for energy and heat generation, pulping, mulching, animal bedding, and other. Utilizing such waste could create job opportunities and generate income for the local companies. The utilization of wood waste in recycling can minimize the gap from supply and demand of lignocellulosic matter. Moreover, it prevents deforestation and contributes to the CO2 offset process. Furthermore, it is possible to obtain add-value materials utilizing the right process for each determined substrate

Benefits and Challenges of Mechanical Spring Systems for Energy Storage Applications

Abstract Storing the excess mechanical or electrical energy to use it at high demand time has great importance for applications at every scale because of irregularities of demand and supply. Energy storage in elastic deformations in the mechanical domain offers an alternative to the electrical, electrochemical, chemical, and thermal energy storage approaches studied in the recent years. The present paper aims at giving an overview of mechanical spring systems' potential for energy storage applications. Part of the appeal of elastic energy storage is its ability to discharge quickly, enabling high power densities. This available amount of stored energy may be delivered not only to mechanical loads, but also to systems that convert it to drive an electrical load. Mechanical spring systems' benefits and limits for storing macroscopic amounts of energy will be assessed and their integration with mechanical and electrical power devices will be discussed

Experimental investigation on CO2methanation process for solar energy storage compared to CO2-based methanol synthesis

The utilization of the captured CO2 as a carbon source for the production of energy storage media offers a technological solution for overcoming crucial issues in current energy systems. Solar energy production generally does not match with energy demand because of its intermittent and non-programmable nature, entailing the adoption of storage technologies. Hydrogen constitutes a chemical storage for renewable electricity if it is produced by water electrolysis and is also the key reactant for CO2 methanation (Sabatier reaction). The utilization of CO2 as a feedstock for producing methane contributes to alleviate global climate changes and sequestration related problems. The produced methane is a carbon neutral gas that fits into existing infrastructure and allows issues related to the aforementioned intermittency and non-programmability of solar energy to be overcome. In this paper, an experimental apparatus, composed of an electrolyzer and a tubular fixed bed reactor, is built and used to produce methane via Sabatier reaction. The objective of the experimental campaign is the evaluation of the process performance and a comparison with other CO2 valorization paths such as methanol production. The investigated pressure range was 2–20 bar, obtaining a methane volume fraction in outlet gaseous mixture of 64.75% at 8 bar and 97.24% at 20 bar, with conversion efficiencies of, respectively, 84.64% and 99.06%. The methanol and methane processes were compared on the basis of an energy parameter defined as the spent energy/stored energy. It is higher for the methanol process (0.45), with respect to the methane production process (0.41–0.43), which has a higher energy storage capability

The Impact of Albedo Increase to Mitigate the Urban Heat Island in Terni (Italy) Using the WRF Model

The impacts of the urban heat island (UHI) phenomenon on energy consumption, air quality, and human health have been widely studied and described. Mitigation strategies have been developed to fight the UHI and its detrimental consequences. A potential countermeasure is the increase of urban albedo by using cool materials. Cool materials are highly reflective materials that can maintain lower surface temperatures and thus can present an effective solution to mitigate the UHI. Terni's proven record of high temperatures along with related environmental and comfort issues in its urban areas have reflected the local consequences of global warming. On the other hand, it promoted integrated actions by the government and research institutes to investigate solutions to mitigate the UHI effects. In this study, the main goal is to investigate the effectiveness of albedo increase as a strategy to tackle the UHI, by using the Weather Research and Forecasting (WRF) mesoscale model to simulate the urban climate of Terni (Italy). Three different scenarios through a summer heat wave in the summer of 2015 are analyzed. The Base Scenario, which simulates the actual conditions of the urban area, is the control case. In the Albedo Scenario (ALB Scenario), the albedo of the roof, walls and road of the whole urban area is increased. In the Albedo-Industrial Scenario (ALB-IND Scenario), the albedo of the roof, walls and road of the area occupied by the main industrial site of Terni, located in close proximity to the city center, is increased. The simulation results show that the UHI is decreased up to 2 °C both at daytime and at nighttime in the ALB and in ALB-IND Scenarios. Peak temperatures in the urban area can be decreased by 1 °C at daytime, and by about 2 °C at nighttime. Albedo increase in the area of interest might thus represent an opportunity to decrease the UHI effect and its consequences

An Innovative Configuration for CO2 Capture by High Temperature Fuel Cells

Many technological solutions have been proposed for CO 2 capture in the last few years. Most of them are characterized by high costs in terms of energy consumption and, consequently, higher fossil fuel use and higher economic costs. High temperature fuel cells are technological solutions currently developed for energy production with low environmental impact. In CIRIAF—University of Perugia labs, cylindrical geometry, small-sized molten carbonate fuel cell (MCFC) prototypes were built and tested with good energy production and lifetime performances. In the present work, an innovative application for MCFCs is proposed, and an innovative configuration for CO 2 capture/separation is investigated. The plant scheme is based on a reformer and a cylindrical MCFC. MCFCs are the most suitable solutions, because CO 2 is used in their operating cycle. An analysis in terms of energy consumption/kgCO 2 captured is made by coupling the proposed configuration with a gas turbine plant. The proposed configuration is characterized by a theoretical energy consumption of about 500 kJ/kgCO 2 , which is quite lower than actual sequestration technologies. An experimental campaign will be scheduled to verify the theoretical findings

May sediments affect the inhibiting properties of NaCl on CH4 and CO2 hydrates formation? an experimental report.

The equilibria of methane and carbon dioxide clathrate hydrates were measured in presence of a pure-quartz porous sand, with and without NaCl. Two different salt concentrations were tested: 0.030 and 0.037 wt%. Results were compared with phase equilibrium data already present in literature for these species. Despite salt, the porous medium was found to promote the process, mainly for the increased surface/volume ratio and for the improved heat transfer. In presence of salt, sand affected the process differently as a function of temperature: at values higher than 3 – 5 °C, it promoted the process, while for values lower than this range, but still greater than the ice-point, it acted as an inhibitor. However, these results can be considered true only for temperatures above the ice point. Due to similarity of ice water with clathrate hydrates, Raman microscale measurements were performed to gather information about the influence of sediments, salt, and temperature on OH-stretching vibrations of water. The obtained results allowed to clarify how the addition of NaCl, and or sediments to liquid water, under different temperature conditions (15 °C and −15 °C), influenced the water hydrogen bonds. Specifically, the changes of OH-stretching vibrations, when correlated with the NaCl concentrations, demonstrated that the presence of sediments partially inhibited the salt effects in the ice water probably due to hydrophilic interactions with the silanol groups of sediments. SEM measurements showed morphological information on sediments and on ice in different experimental conditions

Microrna-221 and Microrna-222 Modulate Differentiation and Maturation of Skeletal Muscle Cells

BACKGROUND:MicroRNAs (miRNAs) are a class of small non-coding RNAs that have recently emerged as important regulators of gene expression. They negatively regulate gene expression post-transcriptionally by translational repression and target mRNA degradation. miRNAs have been shown to play crucial roles in muscle development and in regulation of muscle cell proliferation and differentiation. METHODOLOGY/PRINCIPAL FINDINGS:By comparing miRNA expression profiling of proliferating myoblasts versus differentiated myotubes, a number of modulated miRNAs, not previously implicated in regulation of myogenic differentiation, were identified. Among these, miR-221 and miR-222 were strongly down-regulated upon differentiation of both primary and established myogenic cells. Conversely, miR-221 and miR-222 expression was restored in post-mitotic, terminally differentiated myotubes subjected to Src tyrosine kinase activation. By the use of specific inhibitors we provide evidence that expression of miR-221 and miR-222 is under the control of the Ras-MAPK pathway. Both in myoblasts and in myotubes, levels of the cell cycle inhibitor p27 inversely correlated with miR-221 and miR-222 expression, and indeed we show that p27 mRNA is a direct target of these miRNAs in myogenic cells. Ectopic expression of miR-221 and miR-222 in myoblasts undergoing differentiation induced a delay in withdrawal from the cell cycle and in myogenin expression, followed by inhibition of sarcomeric protein accumulation. When miR-221 and miR-222 were expressed in myotubes undergoing maturation, a profound alteration of myofibrillar organization was observed. CONCLUSIONS/SIGNIFICANCE:miR-221 and miR-222 have been found to be modulated during myogenesis and to play a role both in the progression from myoblasts to myocytes and in the achievement of the fully differentiated phenotype. Identification of miRNAs modulating muscle gene expression is crucial for the understanding of the circuits controlling skeletal muscle differentiation and maintenance

Bile Acid Recognition by NAPE-PLD

The membrane-associated enzyme NAPE-PLD (N-acyl phosphatidylethanolamine specific-phospholipase D) generates the endogenous cannabinoid arachidonylethanolamide and other lipid signaling amides, including oleoylethanolamide and palmitoylethanolamide. These bioactive molecules play important roles in several physiological pathways including stress and pain response, appetite and lifespan. Recently, we reported the crystal structure of human NAPE-PLD and discovered specific binding sites for the bile acid deoxycholic acid. In this study we demonstrate that in the presence of this secondary bile acid, the stiffness of the protein measured by elastic neutron scattering increases, and NAPE-PLD results ~7 times faster to catalyze the hydrolysis of the more unsaturated substrate N-arachidonyl-phosphatidylethanolamine, compared with N-palmitoyl-phosphatidylethanolamine. Chenodeoxycholic acid and glyco- or tauro-dihydroxy conjugates can also bind to NAPE-PLD and drive its activation. The only natural monohydroxy bile acid, lithocholic acid, shows an affinity of ~20 μM and acts instead as a reversible inhibitor (IC(50) ≈ 68 μM). Overall, these findings provide important insights into the allosteric regulation of the enzyme mediated by bile acid cofactors, and reveal that NAPE-PLD responds primarily to the number and position of their hydroxyl groups