Faced with unresolved tensions between neutrino interaction measurements at few-GeV neutrino energies, current experiments are forced to accept large systematic uncertainties to cover discrepancies ...between their data and model predictions. The widely used pion production model in GENIE is compared to four MINERνA charged current pion production measurements using nuisance. Tunings, i.e., adjustments of model parameters, to help match GENIE to MINERνA and older bubble chamber data are presented. We find that scattering off nuclear targets as measured in MINERνA is not in good agreement with expectations based upon scattering off nucleon (hydrogen or deuterium) targets in existing bubble chamber data. An additional ad hoc correction for the low−Q2 region, where collective nuclear effects are expected to be large, is presented. While these tunings and corrections improve the agreement of GENIE with the data, the modeling is imperfect. The development of these tunings within the nuisance framework allows for straightforward extensions to other neutrino event generators and models, and allows omitting and including new datasets as they become available.
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The wind power contribution for the global energy matrix and its technological and commercial maturity becomes an important fact for the sustainable energy development. The CFD studies gain ...importance with the computational progress to improve the efficiency of wind turbines on the aerodynamic criteria. The RANS models show the best relation between accuracy and required computational effort. The present article investigates the application of Arbitrary Mesh Interface (AMI) in transient regime and k-ω SST turbulence model in its standard setting to obtain the Power Coefficient of a small HAWT by using OpenFOAM (pimpleDyMFoam). The numerical results were comparable with the field test results and the numerical results obtained with frozen rotor approach, in stationary regime (simpleFoam) and the same turbulence model. The findings showed good agreement between simulations and experiments. The moving mesh approach with layers addition over the blade's surface, for the adjustment of y+ values, was determinant for the results and reproduced well the three-dimensional dynamic effects of flow for this application. The frozen rotor approach resembled the condition of a stopped rotor and its weaknesses are presented and discussed. The numerical results lied between the highest and the mean experimental values and consistently within the confidence interval.
•CFD studies gain importance to improve the aerodynamic efficiency of wind turbines.•We investigate the Arbitrary Mesh Interface (AMI) and k-ω SST by using OpenFOAM.•The numerical results were comparable to the field test results.•The AMI results were compared to the results obtained with frozen rotor approach.•The results lied consistently between the highest and the mean experimental values.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The higher heating value (HHV) is an important parameter to indicate the energetic potential of biomass from different sources. Bomb calorimeter is the standard to obtain this data; however, in the ...absence of this equipment, estimative through proximate analysis aided with multiple regression formulas is an acceptable alternative. Still, this is a time-consuming technique and highly dependable of operator skills. In this context, thermogravimetric analysis has been used to obtain proximate analysis results with higher precision and demanding a small amount of samples. Here, a simple and effective method to estimate HHV from data obtained by thermogravimetric analysis using different sources of biomass is presented. The proposed method showed to be more accurate to estimate HHV than proximate analysis laboratory procedure. Greater correlation was observed between the HHV values obtained from calorimeter–thermogravimetry than the ones obtained from calorimeter–proximate analysis. Multiple regression analysis indicated that fixed carbon and ashes have an inverse influence over HHV, while the former is responsible for high calorific value and the latter affects energy release. Finally, the proposed method showed to be fast and accurate to estimate HHV of biochar samples and should be easily adaptable to other studies that require fast assessment of calorific value from biochar.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
This work aims at developing an active chitosan film through the incorporation of quercetin and the evaluation of physical and functional properties of the films made thereof. The addition of ...quercetin showed to influence films’ properties in terms of surface morphology, tensile strength, and opacity while elongation-at-break, thickness, water vapor, and oxygen permeability were not significantly affected with incorporation of quercetin. The color parameters of chitosan films were affected by quercetin incorporation with a decrease of the values of
L
* and
a
*. The film exhibited a high free-radical scavenging activity, showing antioxidant activity. The film-forming solutions of chitosan with or without quercetin showed antibacterial activity against four Gram-negative and three Gram-positive bacteria. These results showed that quercetin incorporation in chitosan-based films has potential to be used as a solution for active food packaging.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Muon-neutrino elastic scattering on electrons is an observable neutrino process whose cross section is precisely known. Consequently a measurement of this process in an accelerator-based nu sub(mu) ...beam can improve the knowledge of the absolute neutrino flux impinging upon the detector; typically this knowledge is limited to ~10% due to uncertainties in hadron production and focusing. We have isolated a sample of 135+ or -17 neutrino-electron elastic scattering candidates in the segmented scintillator detector of MINERvA, after subtracting backgrounds and correcting for efficiency. We show how this sample can be used to reduce the total uncertainty on the NuMI flux nu sub(mu) from 9% to 6%. Our measurement provides a flux constraint that is useful to other experiments using the NuMI beam, and this technique is applicable to future neutrino beams operating at multi-GeV energies.
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Angiotensin (Ang)-(1-7) is one of the major active components of the renin-angiotensin system, produced from cleavage of Ang II by angiotensin-converting-enzyme type 2 (ACE2), which acts through a ...specific G protein-coupled receptor, Mas. We have investigated whether the human endometrium expresses these components during menstrual cycle. By radioimmunoassay, Ang-(1-7) was detected in endometrial wash fluid at picomolar concentrations. Using immunofluorescence, both the peptide and its receptor were identified in cultured endometrial epithelial and stromal cells. By immunohistochemistry, Ang(1-7) was localized in the endometrium throughout menstrual cycle, being more concentrated in the glandular epithelium of mid- and late secretory phase. This pattern corresponded to the ACE2 mRNA, which was more abundant in epithelial cells than in stromal cells (2-fold increase, p < 0.05) and in the secretory vs. proliferative phase (6.6-fold increase, p < 0.01). The receptor Mas was equally distributed between epithelial and stromal cells and did not change during menstrual cycle. The physiological role of this peptide system in normal and pathological endometrium warrants further investigation.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
This paper explores a methodology for estimating the minimum time duration of experiments focused on wax deposition studies to be carried out for a passive manifold subsea cooler prototype geometry, ...upon relevant conditions for offshore oil & gas applications. The methodology encompasses 1D thermohydraulic numerical simulations of a CO
2
-rich dense-gas and waxy oil mixture flowing, as well as a mass transfer approach for the wax deposition. The idea is to obtain the minimum measurable impact of wax deposits on the pressure drop and temperature at the locations in which corresponding sensors shall be installed. The results applied to 10 different operational conditions for the cooler prototype are presented and thoroughly discussed, together with the phenomenology of the wax deposition and its relationship with the test conditions (operating pressure, liquid content and gas flow rates) and other important flow parameters, such as the mixture temperature, the occurrence of condensation, the pressure profile, among others. The main conclusions and possible next steps for this work are then outlined.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Due to the growing importance of wind power as a clean and renewable energy source, the use of small-scale wind turbines in urban environments has increased lately. The blade pitch control is an ...effective method to improve the aerodynamic response of a wind turbine, usually applied to large-scale wind turbines. This study presents the effects of varied blade pitch on the aerodynamic performance of a small-size wind turbine. The blades were sketched out according to the Blade Element Moment (BEM) theory, applying the aerodynamic profile NREL-S809 and designed for a tip speed ratio of eight. To analyze the influence of the blade pitch angle on the energy conversion, a comparative study was carried out varying the pitch angle to five different values. Using the analysis of variance (ANOVA), it was possible to demonstrate that blade pitch control could be an effective method also for small-sized wind turbines. A performance chart from the results of blade pitch experiments shows that the power coefficient varies significantly when the angle changes. As conclusion, it is highlighted that an enhanced behavior could be attained by the use of a pitch angle controller resulting in a better recovery of the energy available in the wind.
•The use of small-scale wind turbines in urban environments has increased lately.•Blade pitch control is usually applied only to large-scale wind turbines.•This study shows the effects of blade pitch on the performance of a small HAWT.•A comparative study was carried out varying the pitch angle to five different values.•Findings show that pitch control in small HAWT is suitable in urban environments.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
We report on multinucleon effects in low momentum transfer (<0.8 GeV/c) antineutrino interactions on plastic (CH) scintillator. These data are from the 2010-2011 antineutrino phase of the MINERvA ...experiment at Fermilab. The hadronic energy spectrum of this inclusive sample is well described when a screening effect at a low energy transfer and a two-nucleon knockout process are added to a relativistic Fermi gas model of quasielastic, Δ resonance, and higher resonance processes. In this analysis, model elements introduced to describe previously published neutrino results have quantitatively similar benefits for this antineutrino sample. We present the results as a double-differential cross section to accelerate the investigation of alternate models for antineutrino scattering off nuclei.
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We study neutrino-induced charged-current (CC) π0 production on carbon nuclei using events with fully imaged final-state proton-π0 systems. Novel use of final-state correlations based on transverse ...kinematic imbalance enables the first measurements of the struck nucleon's Fermi motion, of the intranuclear momentum transfer (IMT) dynamics, and of the final-state hadronic momentum configuration in neutrino pion production. Event distributions are presented for (i) the momenta of neutrino-struck neutrons below the Fermi surface, (ii) the direction of missing transverse momentum characterizing the strength of IMT, and (iii) proton-pion momentum imbalance with respect to the lepton scattering plane. The observed Fermi motion and IMT strength are compared to the previous MINERνA measurement of neutrino CC quasielastic-like production. The measured shapes and absolute rates of these distributions, as well as the cross section asymmetries, show tensions with predictions from current neutrino generator models.
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