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Showing papers by "Universidade Federal de Santa Catarina published in 2022"


Journal ArticleDOI
TL;DR: In this article, the microstructure evolution across the welded joints was assessed and rationalized by coupling electron microscopy, high energy synchrotron X-ray diffraction, mechanical property evaluation, and thermodynamic calculations.

95 citations


Journal ArticleDOI
01 Jan 2022
TL;DR: In this article , a functionally graded material (FGM) part was fabricated by depositing a Cu-based alloy on top of a high strength low alloy (HSLA) steel by twin-wire and arc additive manufacturing (TWAAM).
Abstract: In this work, a functionally graded material (FGM) part was fabricated by depositing a Cu-based alloy on top of a high strength low alloy (HSLA) steel by twin-wire and arc additive manufacturing (T-WAAM). Copper and steel parts are of interest in many industries since they can combine high thermal/electrical conductivity, wear resistance with excellent mechanical properties. However, mixing copper with steel is difficult due to mismatches in the coefficient of thermal expansion, in the melting temperature, and crystal structure. Moreover, the existence of a miscibility gap during solidification, when the melt is undercooled, causes serious phase separation and segregation during solidification which greatly affects the mechanical properties. Copper and steel control samples and the functionally graded material specimen were fabricated and investigated using optical microscopy, scanning electron microscopy, and high energy synchrotron X-ray diffraction. Retained δ-ferrite was found in a Cu matrix at the interface region due to regions with mixed composition. A smooth gradient of hardness and electric conductivity along the FGM sample height was obtained. An ultimate tensile strength of 690 MPa and an elongation at fracture of 16.6% were measured in the FGM part.

92 citations


Journal ArticleDOI
TL;DR: In this paper, the authors provide a comprehensive and exhausting analysis of the recent achievements and progress on joining of Al alloys to steel by various laser-based joining processes, including laser keyhole welding, laser welding-brazing, laser-arc welding and laser roll pressure welding and joining based on laser additive manufacturing.

87 citations


Journal ArticleDOI
TL;DR: In this paper , the authors provide a comprehensive and exhausting analysis of the recent achievements and progress on joining of Al alloys to steel by various laser-based joining processes, including laser keyhole welding, laser welding-brazing, laser-arc welding and laser roll pressure welding and joining based on laser additive manufacturing.

87 citations


Journal ArticleDOI
TL;DR: In this paper , the microstructure evolution across the welded joints was assessed and rationalized by coupling electron microscopy, high energy synchrotron X-ray diffraction, mechanical property evaluation, and thermodynamic calculations.

77 citations


Journal ArticleDOI
TL;DR: In this article, the most promising cold plasma sources and operation modes, the influence of the operation conditions on plasma properties, and its efficacity in food processing are discussed. But, the design of safe cold plasma-based processes with minimal impact on quality needs to consider the food composition, packaging molecular structure, and microorganism or targeting molecules concentration.

47 citations


Journal ArticleDOI
TL;DR: In this article , the most promising cold plasma sources and operation modes, the influence of the operation conditions on plasma properties, and its efficacity in food processing are discussed. But, the design of safe cold plasma-based processes with minimal impact on quality needs to consider the food composition, packaging molecular structure, and microorganism or targeting molecules concentration.

44 citations


Journal ArticleDOI
TL;DR: In this paper, a systematic literature review of the state-of-the-art on emotion expression recognition from facial images is presented, where the most commonly used strategies employed to interpret and recognize facial emotion expressions, published over the past few years.

40 citations


Journal ArticleDOI
TL;DR: In this article, the physicochemical properties of pecan nutshell waste (PNS) and its suitability for pyrolytic conversion into bioenergy and bio-based chemicals based on the kinetic triplet, thermodynamic parameters, and Py-GC/MS analysis were investigated.
Abstract: This work reports the first detailed investigation of the physicochemical properties of the pecan nutshell waste (PNS) and its suitability for pyrolytic conversion into bioenergy and bio-based chemicals based on the kinetic triplet, thermodynamic parameters, and Py-GC/MS analysis. The pyrolysis behavior of PNS was assessed using a thermogravimetric analyzer at five heating rate programs under an oxygen-free atmosphere. The Asym2Sig deconvolution function showed that pyrolysis of PNS might be successfully modeled as three parallel devolatilization events (R2 > 99%), which are categorized as the devolatilization of hemicellulose (DE-HC), devolatilization of cellulose (DE-CL), and devolatilization of lignin (DE-LG). The activation energy was obtained for each devolatilization event by concurrent use of four isoconversional methods (Friedman, Flynn-Wall-Ozawa, Kissinger-Akahira-Sunose, and Starink), with average values in the range of 100.3–109.0 kJ mol−1 for DE-HC, 124.3–135.3 kJ mol−1 for DE-CL, and 357.1–398.9 kJ mol−1 for DE-LG. Calculations using the compensation effect method indicated pre-exponential factor values of 5.50 × 108 min−1 for DE-HC, 1.32 × 109 min−1 for DE-CL, and 4.86 × 1018 min−1 for DE-LG. It is inferred that the DE-CL corresponds to a geometrical contraction reaction model while the DE-HC and DE-LG follow order-based reaction models. Finally, the summative kinetic interpretation was successfully obtained based on multiple kinetic triplets, providing a useful mathematical tool able to describe the pyrolysis behavior of PNS. From the thermodynamic viewpoint, PNS has significant potential for application as raw material for bioenergy production. Also, the condensable fraction of the volatile products derived from pecan nutshell pyrolysis is a potential source of valuable bio-based chemicals.

27 citations


Journal ArticleDOI
TL;DR: In this article, the main characteristics of produced water and its different forms of reuse, the theoretical fundaments of the adsorption technique and through case studies, critically evaluate the technical feasibility of implementing ad-sorption towers in PW treatment units.

25 citations


Journal ArticleDOI
TL;DR: In this analysis, Support Vector Machine Classifier provides a good relationship between simplicity and performance, for a fast and useful automatic characterization of microplastics, and is selected as the minimization function target.

Journal ArticleDOI
TL;DR: In this article, a complete description of the primary degenerations and non-degenerations between the 3-dimensional nilpotent algebras, the 4-dimensional commutative algesbras and the 5-dimensional non-nilpotent antic-commodity algesbraes over C is given.

Journal ArticleDOI
TL;DR: In this article, the authors conducted a structured search in a database of scientific articles, selecting comparative studies of direct biodiversity metrics inside and outside MPAs offering different protection levels (i.e., fully or partially-protected MPAs) or within MPAs with distinct zones.

Journal ArticleDOI
TL;DR: A systematic search on the association of phase angle (PhA) with muscle strength and aerobic fitness in different populations was performed in nine electronic databases (CINAHL, LILACS, PubMed, SciELO, Scopus, SPORTDiscus, ScienceDirect, MEDLINE, and Web of Science) in January 2021.

Journal ArticleDOI
TL;DR: In this paper, the authors investigated the kinetics and thermodynamics that describe the pyrolysis of catole coconut through a multi-component approach, aiming to highlight its bioenergy potential.

Journal ArticleDOI
TL;DR: A three-stage block freeze concentration process using minimal instrumental apparatus was studied to concentrate minerals and polyphenols in orange juice, obtaining one cryoconcentrate and one ice fraction at each stage as mentioned in this paper.

Journal ArticleDOI
TL;DR: In this article, a standard framework for data compiling is proposed and an assessment of the uncertainty of variables using entropy and cluster analysis allowed to obtain representative archetypes, and an Artificial Neural Network (ANN) was used as a predictive tool, and it was applied to benchmark a sample of actual buildings.

Journal ArticleDOI
TL;DR: In this paper , optogenetic modulation of D2-MSN to ventral pallidum (VP) projections during different stages of motivated behavior has contrasting effects in motivation; activation at reward delivery decreases motivation; optical inhibition triggers the opposite behavioral effect.

Journal ArticleDOI
TL;DR: In this paper , a standard framework for data compiling is proposed and an assessment of the uncertainty of variables using entropy and cluster analysis allowed to obtain representative archetypes, and an Artificial Neural Network (ANN) was used as a predictive tool, and it was applied to benchmark a sample of actual buildings.

Journal ArticleDOI
TL;DR: In this article, the authors investigated the association between various types of leisure-time physical activity and depression among a large and representative sample, and found that active individuals had lower odds of depression than inactivity.

Journal ArticleDOI
01 Sep 2022
TL;DR: In this article , the grain orientation and mechanical properties of Inconel 625 are tailored by varying the process parameters during directed energy deposition, and it is found that increasing the current is effective in promoting the columnar-to-equiaxed transition due to modifications on the thermal cycle.
Abstract: In this work, the grain orientation and mechanical properties of Inconel 625 are tailored by varying the process parameters during directed energy deposition. Under the same deposition speed, increasing the current is effective in promoting the columnar-to-equiaxed transition due to modifications on the thermal cycle. The solidification conditions (temperature gradient and cooling rate) were characterized during the process. A comparison with an existing solidification map for Inconel 625 indicates that the temperature gradients in the melt pool of the sample fabricated with larger current decrease sufficiently to permit the nucleation and growth of equiaxed grains. Uniaxial tensile testing showed that the sample with equiaxed grain microstructure exhibits a higher yield strength (increase by 36 %) when compared to the sample with columnar grains. Contributions of various strengthening mechanisms to the yield strength are quantified in terms of grain boundary strengthening, dislocation strengthening, and solid-solution strengthening. It is found that the higher yield strength of samples that possess equiaxed grains can be attributed to the enhanced dislocation strengthening arising from the large average Taylor factor.

Journal ArticleDOI
TL;DR: In this article , a mill scale (MS), composed of wüstite, magnetite, and hematite, was used for electrochemical monitoring of the neurotransmitters dopamine (DA), 5-HT, and tryptophan (TRP), biomarkers related to depression diagnostics.

Journal ArticleDOI
TL;DR: In this article, the hydration of orthorhombic C3A (ort-C3A) in sulfate-containing solutions, compared with cubic c3A, was previously related to the differences in crystal structure or the sodium in the pore solution.

Journal ArticleDOI
TL;DR: In this paper, the authors proposed a methodology to evaluate the energy performance of existing zero-energy buildings and to prospect retrofit strategies in a Savannah climate, concerning the A2 scenario of emissions from the Fourth Report of the Intergovernmental Panel on Climate Change.
Abstract: This study proposes a methodology to evaluate the energy performance of existing Zero Energy Buildings and to prospect retrofit strategies in a Savannah climate, concerning the A2 scenario of emissions from the Fourth Report of the Intergovernmental Panel on Climate Change. The selected building to study is recognized for its high energy performance, named Centro SEBRAE de Sustentabilidade (CSS). Two efficient measures were considered: (i) improvement in the air conditioning system coefficient of performance (COP) and (ii) in the energy efficiency of the photovoltaic plates of generation on-site. The methodology is grounded in the potential bioclimatic concept and the employed steps applied were: preparation of climate archives in the 2020, 2050 and 2080 time-slices; calibration of the computational model; evaluation of the retrofit strategies on its energy consumption efficiency through computer simulation. Considering the CSS has already attended mostly the bioclimatic strategies for the local climate and has high efficiency measures in its systems, the retrofit focused the air conditioning and PV system. The isolated retrofit of the air conditioning system was unable to guarantees the NZEB condition despite providing an adequate level of energy efficiency until 2080. The retrofit of the PV system was the only one that provides the NZEB condition for climate change scenarios. The contribution of this paper is to provide a guide to be used in NZEBs, with measures of optimization that provide high potential bioclimatic face to the local where it is built, making it possible to maintain this condition in scenarios of global warming.

Journal ArticleDOI
TL;DR: A literature review of the solution approaches proposed for different MIRP variations, focusing on matheuristic methods that combine heuristic and optimal approaches and are frequently used to solve MIRPs, demonstrated that the proposed algorithms are potentially effective for solving the MIRp when applied to a public dataset.

Journal ArticleDOI
TL;DR: In this article, it was shown how fluid mixtures can be rapidly made buildable, continuously, from pumping to printing with different chemical admixtures, such as setting retarders, accelerators and a PCE-based superplasticizer.

Journal ArticleDOI
TL;DR: In this paper, the void level of a component produced by additive manufacturing can be used to predict the mechanical properties and in most cases it is important to develop processing methodologies able to minimize it.

Journal ArticleDOI
TL;DR: In this article, the biomechanics of traditional titanium Morse taper (MT) dental implants compared to one-piece implants composed of zirconia, polyetheretherketone (PEEK), carbon fiber-reinforced PEEK (CFR-PEEK) or glass fiber reinforced polyethylene (GFR-pEEK) were evaluated using finite element method (FEM).
Abstract: This work aimed to assess the biomechanics, using the finite element method (FEM), of traditional titanium Morse taper (MT) dental implants compared to one-piece implants composed of zirconia, polyetheretherketone (PEEK), carbon fiber-reinforced PEEK (CFR-PEEK), or glass fiber-reinforced PEEK (GFR-PEEK). MT and one-piece dental implants were modeled within a mandibular bone section and loaded on an oblique force using FEM. A MT implant system involving a Ti6Al4V abutment and a cp-Ti grade IV implant was compared to one-piece implants composed of cp-Ti grade IV, zirconia (3Y-TZP), PEEK, CFR-PEEK, or GFR-PEEK. Stress on bone and implants was computed and analyzed while bone remodeling prediction was evaluated considering equivalent strain. In comparison to one-piece implants, the traditional MT implant revealed higher stress peak (112 MPa). The maximum stresses on the one-piece implants reached ~80 MPa, regardless their chemical composition. MT implant induced lower bone stimulus, although excessive bone strain was recorded for PEEK implants. Balanced strain levels were noticed for reinforced PEEK implants of which CFR-PEEK one-piece implants showed proper biomechanical behavior. Balanced strain levels might induce bone remodeling at the peri-implant region while maintaining low risks of mechanical failures. However, the strength of the PEEK-based composite materials is still low for long-term clinical performance.

Journal ArticleDOI
TL;DR: In this paper, a multiphysics routine for calculating annular pressure buildup (APB) in vertical oil wells is proposed, which couples three key aspects influencing the occurrence of APB: (i) the flow of heated hydrocarbons through the well production tubing, which is accounted for with a multi-component, two-phase hydrodynamic model, (ii) a radial, resistance-based thermal model, which determines the multi-modal heat transfer between the production tubing and the surrounding formation, and (iii) a mechanical model which, when coupled to the previous

Journal ArticleDOI
TL;DR: In this paper , the authors reviewed and appraised the existing evidence of residual force enhancement in human skeletal muscles and assessed, through a meta-analysis, the effect of an immediate history of eccentric contraction on the subsequent torque capacity of voluntary and electrically evoked muscle contractions.