Fundamental spray and combustion measurements of soy methyl-ester biodiesel

Although biodiesel has begun to penetrate the fuel market, its effect on injection processes, combustion and emission formation under diesel engine conditions remains somewhat unclear. Typical exhaust measurements from engines running biodiesel indicate that particulate matter, carbon monoxide and unburnt hydrocarbons are decreased, whereas nitrogen oxide emissions tend to be increased. However, these observations are the result of complex interactions between physical and chemical processes occurring in the combustion chamber, for which understanding is still needed. To characterize and decouple the physical and chemical influences of biodiesel on spray mixing, ignition, combustion and soot formation, a soy methyl-ester (SME) biodiesel is injected into a constant-volume combustion facility under diesel-like operating conditions. A range of optical diagnostics is performed, comparing biodiesel to a conventional #2 diesel at the same injection and ambient conditions. Schlieren high-speed imaging shows virtually the same vapour-phase penetration for the two fuels, while simultaneous Mie-scatter imaging shows that the maximum liquid-phase penetration of biodiesel is higher than diesel. Differences in the liquid-phase penetration are expected because of the different boiling-point temperatures of the two fuels. However, the different liquid-phase penetration does not affect overall mixing rate and downstream vapour-phase penetration because each fuel spray has similar momentum and spreading angle. For the biodiesel and diesel samples used in this study, the ignition delay and lift-off length are only slightly less for biodiesel compared to diesel, consistent with the fuel cetane number (51 for biodiesel, 46 for diesel). Because of the similarity in lift-off length, the differences in equivalence ratio distribution at the lift-off length are mainly affected by the oxygen content of the fuels. For biodiesel, the equivalence ratio is reduced, which, along with the fuel molecular structure and oxygen content, significantly affects soot formation downstream. Spatially resolved soot volume fraction measurements obtained by combining line-of-sight laser extinction measurements with planar laser-induced incandescence imaging show that the soot concentration can be reduced by an order of magnitude for biodiesel. These integrated measurements of spray mixing, combustion and quantitative soot concentration provide new validation data for the development of computational fluid dynamics spray, combustion and soot formation models suitable for the latest biofuels.This work was supported by the Spanish Ministry of Science and Innovation for Jean-Guillaume Nerva's visiting research, through the OPTICOMB project [TRA2007-67961-C03-01].Nerva, J.; Genzale, CL.; Kook, S.; García Oliver, JM.; Pickett, LM. (2013). Fundamental spray and combustion measurements of soy methyl-ester biodiesel. 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Challenges in the assessment of medical devices: the MedtecHTA project

Assessing medical devices (MDs) raises challenges which require us to reflect on whether current methods are adequate. Major features of devices are: (i) device–operator interaction can generate learning curve effects; (ii) incremental nature of innovation needs to be addressed by careful identification of the alternatives for comparative and incremental costeffectiveness analysis; and (iii) broader organizational impact in terms of training and infrastructure, coupled with dynamic pricing, requires a more flexible approach to costing. The objective of the MedtecHTA project was to investigate improvements in HTA methods to allow for more comprehensive evaluation of MDs. It consisted of several work packages concerning (i) the available evidence on the currently adopted approaches for regulation and HTA of medical devices; (ii) the geographical variation in access to MDs; (iii) the development of methodological frameworks for conducting comparative effectiveness research and economic evaluation of MDs; and (iv) the organizational impact of MDs. This introductory paper summarizes the main results of the project and draws out the main overarching themes. This supplement represents a comprehensive report of all the main findings of the MedtecHTA project, and it is intended to be the main source for researchers and policy makers wanting information on the project

Improved behavioral indices of welfare in continuous compared to intermittent pair-housing in adult female rhesus macaques (Macaca mulatta).

Limiting opportunities for captive non-human primates (NHPs) to express species-specific social behaviors may disrupt the adaptive drive for social companionship and may lead to increases in coping behaviors and inactivity. While captive NHPs show improved welfare when moving to pair-housing from single-housing, the impact of daily separation of pair-mates, as is implemented in intermittent pair-housing, is not fully understood. We compared behavioral indices of welfare exhibited by adult female rhesus macaques (Macaca mulatta) in two conditions: (1) intermittent pair-housing, involving daily overnight separation of pair-mates, and (2) continuous pair-housing, involving little separation of pair-mates. A within-subjects study design tested two groups of females experiencing both pairing conditions in an alternate order, switching either from continuous to intermittent pair-housing, or from intermittent to continuous pair-housing. Behavioral observations, recording activity state, self-directed, abnormal, and social behaviors, were conducted at midday when all females were paired, and in the afternoon when intermittent pairs were separated. Females exhibited higher levels of inactivity and self-directed behavior when separated due to intermittent pair-housing in comparison to continuous pair-housing. In addition, intermittently paired females showed higher levels of grooming and other types of affiliation when paired, than during the same time frame when they were continuously paired. These results suggest that females in the continuous presence of a social partner experience improved levels of activity and do not need to elevate levels of behavioral coping mechanisms (e.g., self-scratching, increased affiliation) as they receive the benefits associated with social companionship consistently throughout the day. Overall, this study provides the first evidence that continuous pair-housing affords better welfare than intermittent pair-housing in adult female rhesus macaques. Pair-housing options, such as continuous pairing, that reduce reliance on behavioral coping mechanisms and promote adaptive social behavior throughout the entirety of the day should be prioritized over husbandry care scheduled for convenience

Broadening Exposure to Socio-Political Opinions via a Pushy Smart Home Device

Motivated by the effects of the filter bubble and echo chamber phenomena on social media, we developed a smart home device, Spkr, that unpredictably “pushes” socio-political discussion topics into the home. The device utilised trending Twitter discussions, categorised by their socio-political alignment, to present people with a purposefully assorted range of viewpoints. We deployed Spkr in 10 homes for 28 days with a diverse range of participants and interviewed them about their experiences. Our results show that Spkr presents a novel means of combating selective exposure to socio-political issues, providing participants with identifiably diverse viewpoints. Moreover, Spkr acted as a conversational prompt for discussion within the home, initiating collective processes and engaging those who would not often be involved in political discussions. We demonstrate how smart home assistants can be used as a catalyst for provocation by altering and pluralising political discussions within households

Lead-free piezoceramics - Where to move on?

Lead-free piezoceramics aiming at replacing the market-dominant lead-based ones have been extensively searched for more than a decade worldwide. Some noteworthy outcomes such as the advent of commercial products for certain applications have been reported, but the goal, i.e., the invention of a lead-free piezocermic, the performance of which is equivalent or even superior to that of PZT-based piezoceramics, does not seem to be fulfilled yet. Nevertheless, the academic effort already seems to be culminated, waiting for a guideline to a future research direction. We believe that a driving force for a restoration of this research field needs to be found elsewhere, for example, intimate collaborations with related industries. For this to be effectively realized, it would be helpful for academic side to understand the interests and demands of the industry side as well as to provide the industry with new scientific insights that would eventually lead to new applications. Therefore, this review covers some of the issues that are to be studied further and deeper, so-to-speak, lessons from the history of piezoceramics, and some technical issues that could be useful in better understanding the industry demands. As well, the efforts made in the industry side will be briefly introduced for the academic people to catch up with the recent trends and to be guided for setting up their future research direction effectively.ope

Sequential multi-stage extraction of biocompounds from Spirulina platensis: Combined effect of ohmic heating and enzymatic treatment

A sequential multi-stage procedure was applied on the extraction of biocompounds from Spirulina platensis. The process consisted in three steps: 1) aqueous extraction, using conventional thermal extraction (CE), ohmic heating (OH, 7V/cm), enzymatic treatment (EAE, 0.8 mgLysozyme/mL), or both OH and EAE combined; 2) ethanolic extraction; 3) CHCl3/MeOH extraction. The results evidenced that the combined OH-EAE extraction allowed selective recovery of phycobiliproteins in the 1st step, with increments of more than 100% in yield in comparison with CE. Pigments and lipids were selectively extracted in the 2nd step. The combination of OH and EAE in the 1st step resulted in higher amounts of extracted compounds in the following phases compared to processes using non-combined technologies. Results demonstrate that the intensification of extraction steps facilitates the use of environmentally friendly technologies in a multi-stage process capable of recovering and isolating different fractions with bio-functional properties, targeting waste reduction and circular economy. Industrial relevance Spirulina plantensis represents a potential biomass feedstock due to its potential as a source of compounds of great economic value (including antioxidants, proteins, lipids and natural pigments, in particular blue colorants). The combined use of ohmic heating and enzymes in the aqueous extraction step fosters the use of environmentally friendly technologies to implement sequential high yield and high purity extraction of the different valuable fractions with bio-functional properties, targeting waste reduction and contributing to the implementation of circular economy strategies. This can be integrated with a design of Industry 4.0 driving the development of new products.This research was funded by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit, by program Marie Skłodowska-Curie grant (MSCA-RISE; FODIAC; 778388) and by project OH2O - POCI-01-0145-FEDER-029145 (funded by FCT, COMPETE2020 – Competitiveness and Internationalization Operational Program and European Fund for Regional Development - FEDER). Pedro Santos is recipient of a PhD fellowship supported by a doctoral advanced training (call NORTE-69-2015-15), funded by the European Social Fund under the scope of Norte2020 - Programa Operacional Regional do Norte (NORTE-08-5369-FSE-000036). Sílvia Miranda acknowledges the financial support provided by FCT through the Doctoral grant SFRH/BD/144188/2019. Spirulina platensis was kindly supplied by EVRA S.r.l. (Potenza, Italy).info:eu-repo/semantics/publishedVersio