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We report long-baseline interferometric observations with the CHARA Array that resolve six previously known double-lined spectroscopic binary systems in the Hyades cluster, with orbital periods ranging from 3 to 358 days: HD 27483, HD 283882, HD 26874, HD 27149, HD 30676, and HD 28545. We combine those observations with new and existing radial-velocity measurements, to infer the dynamical masses for the components as well as the orbital parallaxes. For most stars, the masses are determined to be better than 1%. Our work significantly increases the number of systems with mass determinations in the cluster. We find that, while current models of stellar evolution for the age and metallicity of the Hyades are able to reproduce the overall shape of the empirical mass–luminosity relation, they overestimate the V -band fluxes by about 0.1 mag between 0.5 and 1.4 M _⊙ . The disagreement is smaller in H , and near zero in K , and depends somewhat on the model. We also make use of the TESS light curves to estimate rotation periods for our targets, and detect numerous flares in one of them (HD 283882), estimating an average flaring rate of 0.44 events per day.

We report spectroscopic observations of vB 120 (HD 30712), a 5.7 yr astrometric–spectroscopic binary system in the Hyades cluster. We combine our radial velocities with others from the literature, and with existing speckle interferometry measurements, to derive an improved 3D orbit for the system. We infer component masses of M _1 = 1.065 ± 0.018 M _☉ and M _2 = 1.008 ± 0.016 M _☉ , and an orbital parallax of 21.86 ± 0.15 mas, which we show to be more accurate than the parallax from Gaia DR3. This is the ninth binary or multiple system in the Hyades with dynamical mass determinations, and one of the examples with the highest precision. An analysis of its spectral energy distribution yields the absolute radii of the stars, R _1 = 0.968 ± 0.012 R _☉ and R _2 = 0.878 ± 0.013 R _☉ , and effective temperatures of 5656 ± 56 K and 5489 ± 60 K for the primary and secondary, respectively. A comparison of these properties with the predictions of current stellar evolution models for the known age and metallicity of the cluster shows only minor differences.

Abstract The main challenge faced by many mechanical engineering educators is the implementation of real solutions during their courses. One alternative can be a realistic case study, where the students can be engaged in the development and analysis process currently applied in the industry. This kind of teaching process not only can be used to improve the quality of teaching‐learning process but also the students can have opportunities to solve real engineering problem. Therefore, this paper reports a realistic case implemented in mechanical engineering courses given in bachelor's and master's degrees. The component under evaluation has been selected considering the student's interest, this criterion was also taken to involve several students into a real project process to their learning development. The same problem was solved during an academic semester, it was solved using different approaches and student's abilities. This procedure can be replicated for students and teachers by following steps. The first step in this process was to describe the theoretical basis for modal analysis to understand how it was structured a numerical finite element model. This model was then solved and simulated using Hypermesh, Optistruct, and HyperView software to obtain numerical modal parameters. On the other, hand, the experimental modal parameters were obtained using a three‐dimensional scanning vibrometer on 60 samples. It is well noted that the implementation of engineering software commonly used at the industry would increase students' confidence. This allows students to perform real problem‐solving activities to develop outcomes as establish goals, plan task, meet deadlines. These activities are extremely important to the actual automotive industry. Therefore, this paper shows an engineering solution process to provide a learning alternative to teach the modal finite method solutions correlation with experimental solutions.

Wood products used in outdoor applications can be degraded by xylophage organisms. For this reason, such products require treatments based on biocides in order to delay their service life. This brings troubles of its own due to the inherent toxicity of these treatments towards humans and the environment. Therefore, it is imperative to find less-toxic natural preservatives. In this context, this work deals with the evaluation of the fungitoxic effect of raw extracts obtained from three types of agroindustrial waste materials: bark of Quercus laeta spp., the cob of Zea mays, and the leaves of Agave tequilana Weber Blue variety. Extracts were incorporated into the test wood Alnus acuminata (Aile wood) via a full-cell process. Bark extracts provided excellent protection against the attack of Trametes versicolor (L. ex. Fr.) Pilát, improving the decay resistance of Aile wood from being nonresistant to resistant. Also, bark extracts from Q. laeta showed less leaching than the other extracts.