Attitudes in Physics Education: An Alternative Approach to Teaching Physics to Non-Science College Students

In this article, we present an alternative way of teaching conceptual physics for non-science majors by depicting the role of physics in today\u27s technology. The goal of this approach is to increase in the minds of non-science students the acceptance of physics as a useful component in general education, and as a major tool in comprehending the present-day technological world experienced by students outside the classroom

Composition of grapes from cv. Trebbiano romagnolo affected by Esca

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Thermal Metrics for Data Centers: A Critical Review

Thermal management and air distribution performance are assuming a key role for achieving the energy saving and the IT equipment reliability for data centers (DCs). In recent years, to monitor and to control their variation several thermal performance metrics were introduced. This work presents a critical review on the most important thermal indices for DCs currently used. The main formulas and physical models on which they are based were discussed. Moreover, a critical analysis on the main advantages and drawbacks of each metric is carried out

Adsorption Capabilities of Fungoid Chitosan Toward Organic Acids in Model Solutions and White Wine

In oenology, fungoid chitosan (CH) can be used as an adjuvant for microbial control, haziness prevention, metal chelation, and ochratoxin removal. In acidic media (such as wine), CH can ionise and interact with charged compounds, giving rise to a series of adsorption and/or removal phenomena, some of which potentially impairing the overall quality of wines. In this context, it is worth noting that the interaction between CH and acidic components of wines has been poorly studied so far, and detailed information on this subject is still lacking. To study those interactions, different doses of chitosan (0.5; 1.0; 2.0 g/L) were dispersed in hydro-alcoholic solution (HS), synthetic wine solution (SW), and white wine (W). Results demonstrated that the remotion of tartaric acid and the change of pH were strongly affected by the matrix and dosage. In W and SW, chitosan was found to adsorb tartaric acid up to about 200 mg/g and 350 mg/g CH, respectively. Accordingly, pH values increased; however, the magnitude depended on the matrix as a consequence of different buffer capacities. Interestingly, even in the absence of tartaric acid (e.g. in HS samples) CH addition caused a pH increase (up to 1.2 units for 2 g/L CH addition) which demonstrated that pH variations may not only depend on the amount of organic acids adsorbed. The chitosan dispersed in W showed the highest average diameter D [3,2] (127.96 μm) compared to the ones dispersed in SW (120.81 μm) and in HS (116.26 μm), probably due to the presence of organic acids on the polymer surface. The minor removal of tartaric acid in W compared to SW could probably depend on the competitive adsorption onto chitosan of other families of compounds present in wine such as polyphenols. The data suggested that chitosan addition could affect the pH and organic acid concentration of all matrices, depending on the doses and composition of the solutions

Characterization of VOCs Emitted by Foliage of Grapevine cv. Isabella for Prospecting Innovative Cropping Systems

Volatile organic compounds play an important role in communication within plants as well as with other organisms. In this work we identified the volatile organic compounds (VOCs) emitted from the foliage of the grapevine cv. Isabella, a largely known hybrid of Vitis vinifera × Vitis labrusca. Our data show 25 VOCs emitted by cv. Isabella. Different compound classes were found, including alcohols, hydrocarbons, esters, terpenes, ketones, and a green leaf volatile (GLV). The study highlighted differences between volatile profiles for diurnal and nocturnal treatments. The compounds: trans-3-dodecene, 5,5 dibutylnonane, ethyl 2-methyllactate, 2-hexanol, 3-ethyl-2-heptanol, 3-nonanol, and 2-nonanol, have not been previously reported for Vitis vinifera foliage. Notably, eight compounds emitted by cv. Isabella, 1-heptanol, 1-octanol, 2-hexanol, 2-nonanone, β-pinene, camphene, cis-hexenyl acetate, and phenethyl alcohol, are of relevant interest for their role in plant defense. New knowledge on the emission of these compounds in cv. Isabella can help to understand the mechanisms of pathogen tolerance of this genotype and could be an important step in prospecting innovative cropping systems

Physico-chemical and sensory characterization of a fruit beer obtained with the addition of cv. Lambrusco grapes must

In 2015, Italian Grape Ale (IGA) beers have been included as a new provisional sub-category of special-type fruit beers by the Beer Judge Certification Program, including those products whose brewing process is carried out in presence of determined quantities of grape must. However, information on the effects of these additions on the composition of final beers are still scarce. This work is hence focused on the chromatic, volatile, phenolic and sensory characterization of IGA beers obtained with the addition of grape musts during brewing process. To this aim, different amounts of must (5, 10 and 20%) from cv. Lambrusco red grapes were added to a lager wort before primary fermentation. Beers were then characterized by HPLC-MS, GC-MS and sensory analysis in order to determine phenolic and aroma compounds along with their sensory attributes. Results confirmed the addition of must from cv. Lambrusco grapes capable to enrich beers in color, acids, phenolic (up to 7-folded increased) and volatile compounds, while giving complexity to beers. These results, which were confirmed by a trained sensory panel, are among the very first insights on the impact of red grape must in brewing, both from a compositional and sensory point of view

Performance characteristics of a hybrid solar receiver combustor utilising hydrogen or syngas

The use of hybrid solar thermal devices, which harness the energy from both concentrated solar radiation and combustion, is receiving growing attention due to their potential to provide a firm and dispatchable thermal energy supply while lowering the costs of energy systems and assisting the penetration of renewable energy. The Hybrid Solar Receiver Combustor (HSRC), which directly integrates the function of a solar receiver and a combustor into a single device, is a particularly promising hybrid technology. Its design allows the receiver to operate in three modes: solar-only, combustion-only and a mixed-mode (a combination of both solar and combustion). Compared with the present state-of-the-art in hybrid solar-combustion systems (which collect the thermal energy from the solar and combustion sources in separate devices and then combine them subsequently), the HSRC offers a reduction in total infrastructure (and hence capital costs), heat-exchange surface area, start-up/shut-down losses and pollutant emissions, due to a reduced need to start-up the back-up combustion plant. Also, the use of the HSRC with renewable fuels (e.g. hydrogen, syngas) offers the additional potential for low-cost carbon neutral or carbon-negative energy, although no data on performance for systems fed with alternative fuels are presently available. To this aim, the present work provides the first direct measurement of the performance of a Hybrid Solar Receiver Combustor (HSRC) fed with hydrogen-based fuels. A laboratory-scale HSRC prototype operated in the Moderate or Intense Low oxygen Dilution (MILD) combustion regime was tested at a nominal capacity of 12-kWth for both the combustion-only and mixed mode, using hydrogen and syngas (H2/CO=2/1 v/v) as fuels. A 5-kWel xenon-arc lamp was used to simulate solar radiation into the device. The influence of the mode of operation on the thermal efficiency, heat losses, heat flux distribution within the cavity and pollutant emissions are reported for a range of values of the heat extraction. It was found that the combustion process can be successfully stabilised within the HSRC over a wide range of operating conditions, and in the mixed-mode of operation, providing ultra-low NOx emissions. The thermal performance was found to be similar for all the modes of operation, despite the different nature of the two energy sources and fuel composition. Overall, this study highlights that, if renewable H2 or syngas are used as fuels, the device can efficiently operate in all the modes of operation employing 100% renewable energy.Alfonso Chinnici, Graham J. Nathan, and Bassam B. Dall

Novelty of Italian Grape Ale (IGA) beer: Influence of the addition of Gamay macerated grape must or dehydrated Aleatico grape pomace on the aromatic profile

: A new category of fruit style beer resulting from the addition of grape matrices is named Italian Grape Ale (IGA). In this paper, we report data on an experimental work to produce IGA beers, adding macerated (CO2 or N2) red Gamay grape must or Aleatico grape pomace resulting from a grape dehydration process. Our hypothesis, that these wine processes can produce volatile organic compounds (VOCs) to characterize these IGA beers which was confirmed by chemical, sensory and aromatic results. IGA beers especially the one with gas-macerated grape musts (IGA-C and IGA-N) showed higher alcohol content than ALE beer (Control) and a higher polyphenol content and antioxidant activity. As regards VOCS, IGA beers increased the concentration of some classes (i.e., alcohols, esters, norisoprenoids) and IGA-N was better characterized by specific compounds such as isobutyric acid, phenylacetate, tyrosol, ethyl hydrogen succinate. Finally, E-nose and sensory evaluation discriminated significantly all the IGA beers

Physico-chemical and sensory characterization of a fruit beer obtained with the addition of cv. Lambrusco grapes must

In 2015, Italian Grape Ale (IGA) beers have been included as a new provisional sub-category of special-type fruit beers by the Beer Judge Certification Program, including those products whose brewing process is carried out in presence of determined quantities of grape must. However, information on the effects of these additions on the composition of final beers are still scarce. This work is hence focused on the chromatic, volatile, phenolic and sensory characterization of IGA beers obtained with the addition of grape musts during brewing process. To this aim, different amounts of must (5, 10 and 20%) from cv. Lambrusco red grapes were added to a lager wort before primary fermentation. Beers were then characterized by HPLC-MS, GC-MS and sensory analysis in order to determine phenolic and aroma compounds along with their sensory attributes. Results confirmed the addition of must from cv. Lambrusco grapes capable to enrich beers in color, acids, phenolic (up to 7-folded increased) and volatile compounds, while giving complexity to beers. These results, which were confirmed by a trained sensory panel, are among the very first insights on the impact of red grape must in brewing, both from a compositional and sensory point of view

Energy-oriented analysis of HPC Cluster Queues: Emerging Metrics for Sustainable Data Center

This work analyzes a very subtle kind of energy metrics for Data Centers (DCs), namely productivity metrics which affect the global energy efficiency assessment in DC since they focus on the energy used for processing computing operations. By exploiting the available set of energy consumption data of operating systems in ENEA-DC, HPC-Cluster, the authors evaluated the energy consumed by different queues with several running applications. The queues energy waste has been calculated to provide an assessment for the ineffective use of computation-related energy load within the Cluster. This work shows an increment innovation beyond state-of-the-art for productivity metrics (e.g. useful work), and it will also help provide an invaluable insight into useful energy use and the use of enhanced sustainability metrics with the goal of driving a more sustainable DC. Additionally, sustainability concept in DC operations is driven by estimation of its indirect carbon emissions, which is shown in this work