Modeling Plain Vacuum Drying by Considering a Dynamic Capillary Pressure

A coupled drying model for wood is proposed by introducing a dynamic capillary pressure. The pressures of non-wetting phase, the wetting phase, and the capillary pressure at equilibrium has been considered as non-static; this approach includes a two-scale model. According to numerical results, liquid, water vapor and air dynamics in the chamber have strong interactions with re-homogenization in the surface, controlled by capillary forces. The results at 60–100 bar and 70 °C are discussed. The phenomenological one-dimensional drying model is solved by using the COMSOL’s coefficient form and a global equation format. A good description of drying kinetics, moisture redistribution, and mass fluxes is obtained. A comprehensible transition at the fiber saturation point is well simulated

Modeling Plain Vacuum Drying by Considering a Dynamic Capillary Pressure

A coupled drying model for wood is proposed by introducing a dynamic capillary pressure. The pressures of non-wetting phase, the wetting phase, and the capillary pressure at equilibrium has been considered as non-static; this approach includes a two-scale model. According to numerical results, liquid, water vapor and air dynamics in the chamber have strong interactions with re-homogenization in the surface, controlled by capillary forces. The results at 60–100 bar and 70 °C are discussed. The phenomenological one-dimensional drying model is solved by using the COMSOL’s coefficient form and a global equation format. A good description of drying kinetics, moisture redistribution, and mass fluxes is obtained. A comprehensible transition at the fiber saturation point is well simulated

Numerical and Experimental Analysis of Sound Suppressor for a 5.56 mm Calibre

A sound suppressor is an internal or external device coupled to the barrel of a firearm. Its development has been historically related to the negative effects produced by the noise. This article presents the numerical and experimental analysis of a sound suppressor for a 5.56 mm caliber rifle. It was designed, manufactured, and tested inside a shooting tunnel for 911 m/s and 344 m/s velocities. Three geometric configurations with curved deflectors, conical deflectors, and finally with a reactive spiral capable of dissipating the acoustic wave were compared considering reactive and dissipative systems. The attenuation of the sound inside the silencer depends directly on the reduction of the projectile wave velocity and the deflagration of the gases at the instant of firing. Then the MIL-STD-1474E standard was used to carry out the experiments. The results in the computational numerical simulation show an average value of 143 dB for the considered three models, the Sound Pressure Level in the reactive core model decreased by 25% with respect to other proposals, which have an average value of 141 dB. These results can be useful to improve in the design of sound suppressors based on the needs of the users and under the specific characteristics of each weapon ballistic.&nbsp

Tannin containing legumes as a model for nutraceuticals against digestive parasites in livestock

Parasitic infections with gastrointestinal nematodes (GINs) still represent a worldwide major pathological threat associated with the outdoor production of various livestock species. Because of the widespread resistance to synthetic chemical anthelmintics, there is a strong impetus to explore novel approaches for a more integrated management of the infections. The use of nutraceuticals in the control of GINs is one of the alternatives which has been widely studied for since 20 years. The objectives of this review are: i) to define and illustrate the concept of ‘nutraceutical’ in the context of veterinary parasitology based on data obtained on the most studied GIN models in small ruminants, the tannin-containing legumes (Fabaceae); ii) to illustrate how the ‘nutraceutical concept’ could be expanded to other plants, other livestock production systems and other GI parasitic diseases, and iii) to explain how this concept is opening up new research fields for better understanding the interactions between the host, the digestive parasites and the environment

Sustainable sugarcane vinasse biorefinement for trans-aconitic acid-based biopolymer synthesis and bioenergy generation

This study aimed at developing a multiproduct biorefinery scheme for vinase valorization. It involved the extraction of trans-aconitic acid, its transformation into biopolymers using microwave irradiation and the use of the raffinated-vinasse for biogas production. Each technology was assessed individually, followed by a process integration at bench scale, from which a mass balance was calculated, supporting the feasibility of the approach. As a renewable source derived from a residue, these bioproducts can replace crude-oil-based materials in various chemical industrial processes; however, a detailed techno-economic and life-cycle analysis are required to defined the sustainability of the process

Physicochemical characterization of mesquite flours

[EN] Ethnic foods are healthy products interesting for the new societies. Mesquite flour offers another option for making gluten-free recipes as part of a diet for people with celiac disease. The physicochemical properties of mesquite flours (Prosopis laevigata) were characterized. The mesquite pods were dried at 60°C, 15% RH and 2 m/s airflow; then a grinding and sieving process were applied. The nutritional composition and the sorption isotherms were obtained at 30, 35, 40 and 45°C for water activities of 0.07-0.9. The particle-size distribution, morphology and thermal stability of the flours were determined by different methods.The authors are grateful to Conacyt for the scholarship granted to Larissa Reyes, and to the Instituto Politénico Nacional (Mexico) for SIP funding 20161016 and 20170755. Thanks to Dr. P. F. de Jesús Cano Barrita and M.C. Frank León Martinez for their technical assistance in the use of SEM microscope.Sandoval Torres, S.; Reyes López, L.; Méndez Lagunas, L.; Rodríguez Ramírez, J.; Barriada Bernal, G. (2018). Physicochemical characterization of mesquite flours. En IDS 2018. 21st International Drying Symposium Proceedings. Editorial Universitat Politècnica de València. 989-996. https://doi.org/10.4995/IDS2018.2018.7707OCS98999

Análisis cuantitativo de ácidos grasos en harina de Prosopis laevigata

Ripe mesquite pods are widely consumed by humans and animals in arid and semi-arid areas for their protein, carbohydrate, crude fiber and fat contents. The goal of this work is to identify and to quantify the fatty acid profile of flour from mesquite pods. Structural assignments were confirmed by the analysis of fragmentation patterns of mass spectra obtained by GC-MS. The results showed that 75% of the fatty acids were unsaturated, of which linoleic acid was predominant, while palmitic and stearic acids, and saturated fatty acids were found in minor proportions.Las vainas de mezquite maduro son ampliamente consumidas por humanos y animales en las zonas áridas y semiáridas por su contenido de proteínas, carbohidratos, fibra cruda y grasas. El propósito de este trabajo es identificar y cuantificar el perfil de ácidos grasos de harinas de vainas mezquite. La estructura química fue confirmada mediante el análisis de los fragmentos del espectro de masas obtenidos por GC-MS. Los resultados mostraron que el 75% de los ácidos grasos fueron insaturados, de los cuales, el ácido linoleico predomina mientras que el ácido pálmico y esteárico, ambos ácidos grasos saturados, fueron encontrados en menor proporción

Relationship between Serum Concentration of Uric Acid and Insulin Secretion among Adults with Type 2 Diabetes Mellitus

To determine the relationship between serum concentrations of uric acid and insulin secretion with hyperglycaemic clamp technique among adults with type 2 diabetes mellitus (DM2) without hyperuricemia, we carried out a cross-sectional study on 45 patients of both gender. We observed correlation between uric acid with male gender r = 0.710 (P = 0.001). Also correlation between uric acid and total insulin secretion was positive r = 0.295 (P = 0.049). As well as a positive correlation adjusted for body mass index was demonstrated for the first, second, and total phases of insulin secretion, respectively, r = 0.438 (P = 0.022), r = 0.433 (P = 0.022), and r = 0.439 (P = 0.024). Serum concentration of uric acid showed a positive relationship with the total phase of insulin secretion; even in states prior to hyperuricemia, uric acid can play an important role in the function of the beta cell in patients with DM2