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Increasing concern about climate change and the need to reduce dependence on fossil fuels have driven the search for more sustainable energy alternatives. One way to reduce emissions is by adding oxygenated compounds such as biodiesel and alcohols to diesel fuel. However, this can lead to phase separation between the fuels and have serious consequences for engine performance. In this context, the present study aimed to evaluate the effect of ethanol content on the miscibility of components in mixtures containing ethanol + biodiesel + diesel through the study of liquid-liquid equilibrium. The results from ternary phase diagrams revealed that the amount of water present in ethanol has a significant effect on the miscibility of the mixture components, with larger biphasic regions observed in systems with lower ethanol content. For the 95% ethanol diagram, the reliability of experimental data on equilibrium lines was assessed through the Othmer-Tobias and Hand correlations, which showed correlation coefficients (R²) of 0.996 and 0.995, respectively. The results obtained from the NRTL and UNIQUAC thermodynamic models demonstrated excellent agreement with the experimental data, with a deviation of only 1.78 and 0.78% for the NRTL and UNIQUAC models. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ingeniería de Construcción is the property of Revista Ingenieria de Construccion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Unmanned Aerial Vehicles (UAVs) are adopted in different applications, such as mapping, logistics, and surveillance. For some applications, it is important to identify people or objects to be tracked in the image and define their coordinates in the object space. It can be done by using a photogrammetric process called Monoplotting. Moreover, by applying the Propagation of Variance and Covariance, the standard deviation from planimetric coordinates can be defined as an Exterior Orientation Parameter (EOP) function. This work evaluates the planimetric accuracy achieved using points defined in UAV images and the impact of EOPs precision. Two UAV images, the Digitals Surface Model (DSM) from the corresponding areas, the EOPs (X0, Y0, Z0, ω, φ, κ), and the platform/sensors characteristics were used for the experiments. Results showed that planimetric precision is low when using UAVs with a low-cost positioning system, especially if the points of interest in the image are far from the nadir. For UAVs with a high-precision positioning system, Inertial Measurement Unit (IMU) system is the one with a higher influence on the accuracy of planimetric coordinates, especially for oblique photographs (essential for UAV routing when avoiding obstacles). The impact of the IMU system precision increases in oblique photographs, this alerts to attention for UAV flight real-time routing guided by obstacles mapping using images. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mining & Metallurgy. Section B: Metallurgy is the property of Journal of Mining & Metallurgy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, we present a simple domain decomposition code based on the Galerkin-Collocation method to integrate the field equations of the Bondi problem. The algorithm is stable, exhibits exponential convergence when considering the Bondi formula as an error measure, and is computationally economical. We have incorporated features of both Galerkin and Collocation methods along with the establishment of two nonoverlapping subdomains. We have further applied the code to show the decay of the Bondi mass in the nonlinear regime and its power-law late-time decay. Another application is the determination of the waveforms at the future null infinity connected with distinct initial data. [ABSTRACT FROM AUTHOR]

Transport processes around the magnetic X-point of tokamaks, such as turbulence and mean-field drifts, are scarcely understood. The assessment of the capability of turbulence codes to quantitatively reproduce these dynamics has been hampered by limitations in computational power and available experimental data. In this paper, we present a rigorous validation of full-scale simulations of a newly developed X-point scenario in the basic toroidal plasma device TORPEX, performed with the four state-of-the-art codes FELTOR, GBS, GRILLIX, and STORM. High-resolution Langmuir probe array measurements of various time-averaged and fluctuating quantities and across the entire cross section of TORPEX show that this X-point scenario features the key ingredients of X-point dynamics, such as small-scale fluctuations and background drifts. The codes are able to qualitatively reproduce some characteristics of the time-averaged fields, such as the ion saturation current profiles at mid-height, the plasma up-down asymmetry, and the blob trajectories. A quantitative agreement is found for the background E × B velocity pattern, while the fluctuation levels are generally underestimated typically by factors of 2 or more, and thus, background fluxes are found to dominate over turbulent ones in simulations. The sensitivity of the simulation results on the plasma collisionality and on the position of the sources is tested in GBS, showing a mild effect on the overall quantitative agreement with the experiment. Overall, this validation reveals the challenges to reproduce the plasma dynamics near an X-point and provides a clear path to a quantitative and computationally relatively inexpensive assessment of future developments in turbulence codes. [ABSTRACT FROM AUTHOR]

This work presents a quantitative test of SOLPS-ITER simulations against tokamak à configuration variable (TCV) L-mode experiments. These simulations account for drifts, currents, kinetic neutrals, and carbon impurities providing the most complete edge transport simulations for TCV to date. The comparison is performed on nominally identical discharges carried out to assess the effectiveness of TCV's divertor baffles in the framework of the European Plasma Exhaust program and employs numerous edge diagnostics providing a detailed code-experiment benchmark for TCV. The simulations show a qualitative consistency, but the quantitative differences remain, which are assessed herein. It is found that, for a given separatrix density, the simulations most notably yield a colder, and denser, divertor state with a higher divertor neutral pressure than measured. [ABSTRACT FROM AUTHOR]

The current article debated over the Brazilian trade policy, bringing evidence about the impacts of the liberal reformation done at the beginning of the 1990s. Complementary the study discusses different points of view on the literature on impacts a liberalisation can have on the national economies as well as the evidence of the benefits of expanding the international trade. [ABSTRACT FROM AUTHOR]

The classical Kelvin–Voigt equations for incompressible fluids with non-constant density are investigated in this work. To the associated initial-value problem endowed with zero Dirichlet conditions on the assumed Lipschitz-continuous boundary, we prove the existence of weak solutions: velocity and density. We also prove the existence of a unique pressure. These results are valid for d ∈ {2, 3, 4}. In particular, if d ∈ {2, 3}, the regularity of the velocity and density is improved so that their uniqueness can be shown. In particular, the dependence of the regularity of the solutions on the smoothness of the given data of the problem is established. [ABSTRACT FROM AUTHOR]

A detailed description of the construction and commissioning of the fast-moving reciprocating divertor Langmuir probe array on the Tokamak à Configuration Variable (TCV) is presented. A horizontal array of 24 Langmuir probes (12 Mach probes) combined with a fast vertical movement provides unprecedented two-dimensional measurements of the plasma properties across the entire divertor outer leg volume and up to the X-point. The L-shape probe arm has to be very compact to minimize plasma perturbations and, at the same time, has to house 24 coaxial transmission lines, withstand time-averaged heat fluxes of up to ≈30 MW/m2 and accelerations of up to 8 g, and be resilient to violent plasma disruptions. For the fast vertical motion of the probe arm, extending up to 38 cm into the TCV vacuum vessel, an assembly with a precise and powerful linear electric motor (up to 4000 N of force) was mounted in a 4 m high structure within the limited space below the TCV. The diagnostic has already performed measurements in ≈200 plasma discharges and has been hit by ≈20 disruptions without suffering any critical damage. The measurements are qualitatively and quantitatively consistent with other reference diagnostics, such as upstream electron Thomson scattering and downstream wall-embedded Langmuir probes, and are used extensively on the TCV for experimental divertor studies and for comparisons with edge transport and turbulence code results. [ABSTRACT FROM AUTHOR]

This work is the continuation of the investigation of aspects of wave turbulence in preheating we started in [J. A. Crespo and H. P. de Oliveira, J. Cosmol. Astropart. Phys. 12 (2019) 045; (2014) 006] but considering several classes of inflationary two-field models. We exhibit the main elements of the wave turbulence phase imprinted in the power spectra of relevant quantities in the time and space domains. As a general feature, the power spectra resemble in their structure to those obtained using the single nonminimally coupled scalar field of the previous work. As a consequence, we obtained an estimate of the temperature corresponding to the thermalized phase from the power spectrum of the total energy density. Another feature allowed by the simulations was the determination of the effective equation of state after taking into account the backreaction of the produced particles. [ABSTRACT FROM AUTHOR]

The Tokamak ŕ Configuration Variable (TCV) tokamak is in the midst of an upgrade to further its capability to investigate conventional and alternative divertor configurations. To that end, modular and removable gas baffles have been installed to decrease the coupling between the divertor and the plasma core. The baffles primarily seek to suppress the transit of recycling neutrals to closed flux surfaces. A first experimental campaign with the gas baffles has shown that the baffled divertor remains compatible with a wide range of configurations including snowflake and super-X divertors. Plasma density ramp experiments reveal an increase of the neutral pressure in the divertor by up to a factor ×5 compared to the unbaffled divertor and thereby qualitatively confirm simulations with the SOLPS-ITER code that were used to guide the baffle design. Together with a range of new and upgraded divertor diagnostics, the baffled TCV divertor is now used to validate divertor models for ITER and next step devices with particular emphasis on geometric variations. [ABSTRACT FROM AUTHOR]

Wavelets are closely related to Schrödinger's wave functions and the interpretation of Born. Similar to the appearance of atomic orbital, it is proposed to combine anti-symmetric wavelets into orbital wavelets. The proposed approach allows the increase of the dimension of wavelets through this process. New orbital 2D-wavelets are introduced for the decomposition of still images, showing that it is possible to perform an analysis simultaneously in two distinct scales. An example of such an image analysis is shown. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the effect of carbodiimide (EDC) and chlorhexidine (CHX) on the bond strength (BS) of resin cement to root dentine of teeth submitted to radiotherapy. Methodology: One hundred and twenty extracted maxillary canines were selected and assigned to 2 groups (n = 60): nonirradiated and irradiated (30 cycles of 2 Gy, total 60 Gy). Roots lengths were standardized, and canals were prepared and filled. Post spaces were then prepared, and the samples were redistributed according to dentine treatment (n = 20): saline solution (SF); CHX 2%; or EDC 0.5M. After drying the post space, fibreglass posts were cemented. Cross‐sectioned slices were obtained, and in half of the specimens of each subgroup (n = 10), the analysis was performed immediately; the others (n = 10) were stored for 10 months before analyses. The most cervical slice of each third was subjected to a push‐out test and failure pattern analysis (n = 10), and the most apical slice submitted to the analysis of the adhesive interface by SEM (n = 5). The bond strength data were submitted to anova and Tukey tests, the adhesive interface adaptation was submitted to Kruskal–Wallis and Dunn's tests, and the Chi‐square test was used to evaluate the type of failure. Results: The irradiated specimens had significantly lower bond strength (13.8 ± 4.3) than the nonirradiated (18.1 ± 3.1; P < 0.001). For the irradiated teeth, the bond strengths were significantly lower in the SF and CHX groups (P < 0.001). Also, the bond strengths reduced significantly after 10 months in the SF and CHX groups (P < 0.001). Cohesive failures occurred in dentine for irradiated specimens. Poorer interface adaptation, dentine fractures and microfractures were observed in irradiated specimens, and better adaptation was observed for specimens after EDC treatment. Conclusions: Radiotherapy was associated with lower bond strength and worse interface adaptation. Dentine treatment with EDC contributed to adhesive interface longevity during the cementation of glass fibre posts in nonirradiated and irradiated teeth. [ABSTRACT FROM AUTHOR]