cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.5669206
title: Characterization and Evaluation of Ceramic Properties with Spherical and Prismatic Samples of Clay Used in Red Ceramics

description: The Brazilian red ceramic industry monthly consumes about 10.3 million tons of clay, its main raw material. In most potteries, characterization of the clay is made empirically, which can result in roof tiles and blocks not according to standards. In this sense, this paper aims to characterize clays used in the manufacturing of red ceramic products in a factory located in Colatina-ES, which appears as a ceramic pole with about twenty small and midsize industries. The clays were characterized by: X-ray fluorescence, X-ray diffraction, thermal analysis (DSC/TG), granulometry, Atterberg limits and content of organic matter. Specimens of clay and mixture containing four clays were shaped. Specimens were shaped, dried at 110°C, and burned at 850ºC in an industrial furnace-type tunnel for 24 hours. The ceramics and mechanical properties evaluated were: mechanic strength, water absorption, apparent porosity, apparent specific mass and shrinkage by drying and firing. The characterization showed that kaolinitic clay presents high plasticity, but high porosity. The mixture formed by the four clays does not meet the requirements of the Brazilian standard clays for red ceramic. It is possible to confirm the use of the methodology of the spheres in potteries for analysis of ceramics raw materials.
DOI: 10.6084/m9.figshare.5669206.v1
title: Characterization and Evaluation of Ceramic Properties with Spherical and Prismatic Samples of Clay Used in Red Ceramics

description: The Brazilian red ceramic industry monthly consumes about 10.3 million tons of clay, its main raw material. In most potteries, characterization of the clay is made empirically, which can result in roof tiles and blocks not according to standards. In this sense, this paper aims to characterize clays used in the manufacturing of red ceramic products in a factory located in Colatina-ES, which appears as a ceramic pole with about twenty small and midsize industries. The clays were characterized by: X-ray fluorescence, X-ray diffraction, thermal analysis (DSC/TG), granulometry, Atterberg limits and content of organic matter. Specimens of clay and mixture containing four clays were shaped. Specimens were shaped, dried at 110°C, and burned at 850ºC in an industrial furnace-type tunnel for 24 hours. The ceramics and mechanical properties evaluated were: mechanic strength, water absorption, apparent porosity, apparent specific mass and shrinkage by drying and firing. The characterization showed that kaolinitic clay presents high plasticity, but high porosity. The mixture formed by the four clays does not meet the requirements of the Brazilian standard clays for red ceramic. It is possible to confirm the use of the methodology of the spheres in potteries for analysis of ceramics raw materials.
DOI: 10.6084/m9.figshare.5669203
title: Cellular Ceramics Produced from Ceramic Shell: Processing and Characterization

description: In this work, ceramic shell (mullite source), an industrial solid waste from the lost-wax casting process, after crushing and milling steps, was used and evaluated as an alternative raw material source for the production of cellular ceramics for high temperature applications (&gt; 1400 °C). The obtained ceramic shell powder, with particle size distribution (d50 &lt; 2 µm) suitable for the production of ceramic foams, was characterized from the point of view of their physical, chemical, morphological and crystallographic properties. Samples were prepared and obtained by direct foaming and gelcasting routes, dried at room temperature and then fired in two steps (650 °C/2 h and 1550 °C/2 h), and cooled in the furnace to room temperature. The effects of solids loading (35 and 42 vol. %) and stirring velocity (500 and 2000 rpm) on the cellular structure (pore size distribution and porosity) and mechanical properties of the produced ceramic shell foam samples were evaluated. The results showed that it is possible to obtain ceramic foams based on mullite-zirconite, with pore sizes between 100 and 900 µm, porosities up to 77% and compressive strength varying from 3 to 20 MPa.
DOI: 10.6084/m9.figshare.5669203.v1
title: Cellular Ceramics Produced from Ceramic Shell: Processing and Characterization

description: In this work, ceramic shell (mullite source), an industrial solid waste from the lost-wax casting process, after crushing and milling steps, was used and evaluated as an alternative raw material source for the production of cellular ceramics for high temperature applications (&gt; 1400 °C). The obtained ceramic shell powder, with particle size distribution (d50 &lt; 2 µm) suitable for the production of ceramic foams, was characterized from the point of view of their physical, chemical, morphological and crystallographic properties. Samples were prepared and obtained by direct foaming and gelcasting routes, dried at room temperature and then fired in two steps (650 °C/2 h and 1550 °C/2 h), and cooled in the furnace to room temperature. The effects of solids loading (35 and 42 vol. %) and stirring velocity (500 and 2000 rpm) on the cellular structure (pore size distribution and porosity) and mechanical properties of the produced ceramic shell foam samples were evaluated. The results showed that it is possible to obtain ceramic foams based on mullite-zirconite, with pore sizes between 100 and 900 µm, porosities up to 77% and compressive strength varying from 3 to 20 MPa.
DOI: 10.6084/m9.figshare.5669200
title: Microstructure and Mechanical Properties of Ti-12Mo-8Nb Alloy Hot Swaged and Treated for Orthopedic Applications

description: Metastable β-type Ti alloys with non-toxic addition elements such as Mo, Zr, Sn, Ta and Nb were developed as an alternative to the widely used Ti-6Al-4V alloy for biomedical applications. These alloys possess enhanced biocompatibility and reduced elastic modulus in comparison with Ti-6Al-4V. Moreover, for orthopedic implants, low Young's modulus is required in order to avoid the stress shielding phenomenon. This study analyzes the microstructure and mechanical properties of a new Ti-12Mo-8Nb alloy after hot swaging, annealing at 950 ºC for 1h and water quenching. The alloy was characterized by X-ray diffraction, optical microscopy and transmission electron microscopy. Tensile tests were performed at room temperature. Young's modulus and hardness values were also measured. The structural characterization reveals a metastable β structure containing only a small amount of α and ω phases. Exhibiting a lower Young's modulus than Ti-6Al-4V and other previously studied Ti-Mo-Nb alloys, the Ti-12Mo-8Nb alloy can be a promising alternative for orthopedic application.
DOI: 10.6084/m9.figshare.5669200.v1
title: Microstructure and Mechanical Properties of Ti-12Mo-8Nb Alloy Hot Swaged and Treated for Orthopedic Applications

description: Metastable β-type Ti alloys with non-toxic addition elements such as Mo, Zr, Sn, Ta and Nb were developed as an alternative to the widely used Ti-6Al-4V alloy for biomedical applications. These alloys possess enhanced biocompatibility and reduced elastic modulus in comparison with Ti-6Al-4V. Moreover, for orthopedic implants, low Young's modulus is required in order to avoid the stress shielding phenomenon. This study analyzes the microstructure and mechanical properties of a new Ti-12Mo-8Nb alloy after hot swaging, annealing at 950 ºC for 1h and water quenching. The alloy was characterized by X-ray diffraction, optical microscopy and transmission electron microscopy. Tensile tests were performed at room temperature. Young's modulus and hardness values were also measured. The structural characterization reveals a metastable β structure containing only a small amount of α and ω phases. Exhibiting a lower Young's modulus than Ti-6Al-4V and other previously studied Ti-Mo-Nb alloys, the Ti-12Mo-8Nb alloy can be a promising alternative for orthopedic application.
DOI: 10.6084/m9.figshare.5669194
title: Serosurvey for Leishmania spp., Toxoplasma gondii, Trypanosoma cruzi and Neospora caninum in neighborhood dogs in Curitiba-Paraná, Brazil

description: Abstract Neighborhood dogs may act as reservoirs for several zoonotic protozoan infections, particularly in urban areas, thus constituting a potential public health threat. Accordingly, the aim of the present study was to evaluate the exposure of neighborhood dogs to four protozoan pathogens in public areas with high levels of human movement in Curitiba, southern Brazil. Blood samples from 26 neighborhood dogs were screened by means of the indirect immunofluorescent antibody test (IFAT) for Leishmania spp., Toxoplasma gondii, Trypanosoma cruzi and Neospora caninum, and a questionnaire was answered by the respective keeper. A total of 8/26 dogs (30.7%) seroreactive to T. gondii, 3/26 (11.5%) to N. caninum and 2/26 (7.7%) to both were identified. All the samples were seronegative for T. cruzi and Leishmania spp. Pathogen seroreactivity was not associated with the daily human movements or other epidemiological variables investigated (p &gt; 0.05). In conclusion, the low seroprevalence for T. gondii and N. caninum indicated low environmental and food risk for animal infection and the seronegativity for Leishmania spp. and T. cruzi may reflect the absence of these pathogens in urban areas of Curitiba. Moreover, neighborhood dogs may be used as environmental sentinels for the presence of protozoan pathogens and their vectors.
DOI: 10.6084/m9.figshare.5669194.v1
title: Serosurvey for Leishmania spp., Toxoplasma gondii, Trypanosoma cruzi and Neospora caninum in neighborhood dogs in Curitiba-Paraná, Brazil

description: Abstract Neighborhood dogs may act as reservoirs for several zoonotic protozoan infections, particularly in urban areas, thus constituting a potential public health threat. Accordingly, the aim of the present study was to evaluate the exposure of neighborhood dogs to four protozoan pathogens in public areas with high levels of human movement in Curitiba, southern Brazil. Blood samples from 26 neighborhood dogs were screened by means of the indirect immunofluorescent antibody test (IFAT) for Leishmania spp., Toxoplasma gondii, Trypanosoma cruzi and Neospora caninum, and a questionnaire was answered by the respective keeper. A total of 8/26 dogs (30.7%) seroreactive to T. gondii, 3/26 (11.5%) to N. caninum and 2/26 (7.7%) to both were identified. All the samples were seronegative for T. cruzi and Leishmania spp. Pathogen seroreactivity was not associated with the daily human movements or other epidemiological variables investigated (p &gt; 0.05). In conclusion, the low seroprevalence for T. gondii and N. caninum indicated low environmental and food risk for animal infection and the seronegativity for Leishmania spp. and T. cruzi may reflect the absence of these pathogens in urban areas of Curitiba. Moreover, neighborhood dogs may be used as environmental sentinels for the presence of protozoan pathogens and their vectors.
DOI: 10.6084/m9.figshare.5669185
title: Specific heats of degenerate ideal gases

description: From arguments based on Heisenberg's uncertainty principle and Pauli's exclusion principle, the molar specific heats of degenerate ideal gases at low temperatures are estimated, giving rise to values consistent with the Nerst-Planck Principle (third law of Thermodynamics). The Bose-Einstein condensation phenomenon based on the behavior of specific heat of massive and non-relativistic boson gases is also presented.
DOI: 10.6084/m9.figshare.5669182
title: Study of the relationship between circular uniform movement and simple harmonic movement using video analysis of a bicycle wheel

description: In this article we discuss the results of a video analysis that allows us to study the relationship between uniform circular motion (UCM) and simple harmonic motion (SHM), from the filming of the circular motion of a bicycle wheel. Considering a fixed point P at the wheel's edge, in a circular motion of radius R and angular coordinate φ, we can obtain its Cartesian components x and y by means of video analysis, observing that they oscillate over time. Assuming the motion of P as an MCU, we obtain analytically the x and y coordinates, comparing them with the coordinates obtained by video analysis. The model allows explicit study of the relationship between UCM and SHM, in addition to providing the bicycle radius with accuracy of 1%.
DOI: 10.6084/m9.figshare.5669179
title: Influence of Si Coating on Interfacial Microstructure of Laser Joining of Titanium and Aluminium Alloys

description: A common phenomenon in the dissimilar joints is the presence of brittle compounds in the joining interface region. The brittle phases can decrease by introduction of interlayers in the joining interface, such as silicon, that inhibits the formation of Al3Ti and AlTi3 phases in joining process between titanium and aluminium alloys. In the present work, the joining of titanium and aluminium alloys have been carried out using a Yb:fiber laser, considering the prior silicon film deposited on titanium alloy interface by DC magnetron sputtering. Butt joint conditions were maintained constant: laser average power, process speed and beam positioning along the interface joining toward aluminium alloy (1200 W, 3.0 m/min and 0.3 mm, respectively). Metallographic analyses were carried out on the cross-section joint by optical and electronic microscopies. When the melted aluminium alloy wet the solid-state titanium alloy, a more restrict compound layer was formed in the joining interface. EDS line scanning in the joining interface showed a reduction of compound layer thickness, considering the silicon as interlayer, reaching the mean value of 3 µm, i.e., up to five times thinner if compared to joining without silicon during the process.
DOI: 10.6084/m9.figshare.5669179.v1
title: Influence of Si Coating on Interfacial Microstructure of Laser Joining of Titanium and Aluminium Alloys

description: A common phenomenon in the dissimilar joints is the presence of brittle compounds in the joining interface region. The brittle phases can decrease by introduction of interlayers in the joining interface, such as silicon, that inhibits the formation of Al3Ti and AlTi3 phases in joining process between titanium and aluminium alloys. In the present work, the joining of titanium and aluminium alloys have been carried out using a Yb:fiber laser, considering the prior silicon film deposited on titanium alloy interface by DC magnetron sputtering. Butt joint conditions were maintained constant: laser average power, process speed and beam positioning along the interface joining toward aluminium alloy (1200 W, 3.0 m/min and 0.3 mm, respectively). Metallographic analyses were carried out on the cross-section joint by optical and electronic microscopies. When the melted aluminium alloy wet the solid-state titanium alloy, a more restrict compound layer was formed in the joining interface. EDS line scanning in the joining interface showed a reduction of compound layer thickness, considering the silicon as interlayer, reaching the mean value of 3 µm, i.e., up to five times thinner if compared to joining without silicon during the process.
DOI: 10.6084/m9.figshare.5669176
title: On Einstein's theory for gravitational waves and their application in the study of the radiation emitted by a binary pulsar

description: In this work we show a deduction of the wave equation related to the so-called gravitational waves. We will see that these waves arise naturally as solutions of the linearized Einstein equations, after choosing a suitable coordinate system (gauge). We will also discuss the generation of gravitational waves and the quadrupolar nature of gravitational radiation emitted by a binary system in circular orbit. Finally, we will apply the theory developed in the observational data of the Hulse-Taylor binary, thus obtaining notion of the values that involve this kind of event and how accurate the theory is.
DOI: 10.6084/m9.figshare.5669173
title: Determination of the Mechanical Properties of Epoxy Silica Nanocomposites through FEA-Supported Evaluation of Ball Indentation Test Results

description: In the present paper a continuous Finite Element Analysis (FEA) simulation method of the ball indentation hardness test is introduced in order to describe the deformation behavior of nanosilica composites and with this to extract precisely the material's stress-strain behavior. The developed procedure demonstrate in particular the adequacy of this method to determine the nanocomposites' elastic modulus which is compared with Halpin-Tsai and Lewis-Nielsen models as well as with experimental measurements taken from uniaxial tensile tests. The fracture area of all the tensile specimens was examined using a scanning electron microscope (SEM). It is shown that the correlation between the experimental results, the semi-empirical models and the FEA computational models concerning the elastic modulus values was satisfactory with very small deviations.
DOI: 10.6084/m9.figshare.5669173.v1
title: Determination of the Mechanical Properties of Epoxy Silica Nanocomposites through FEA-Supported Evaluation of Ball Indentation Test Results

description: In the present paper a continuous Finite Element Analysis (FEA) simulation method of the ball indentation hardness test is introduced in order to describe the deformation behavior of nanosilica composites and with this to extract precisely the material's stress-strain behavior. The developed procedure demonstrate in particular the adequacy of this method to determine the nanocomposites' elastic modulus which is compared with Halpin-Tsai and Lewis-Nielsen models as well as with experimental measurements taken from uniaxial tensile tests. The fracture area of all the tensile specimens was examined using a scanning electron microscope (SEM). It is shown that the correlation between the experimental results, the semi-empirical models and the FEA computational models concerning the elastic modulus values was satisfactory with very small deviations.
DOI: 10.6084/m9.figshare.5669170
title: Low-cost automatic station for compost temperature monitoring

description: ABSTRACT Temperature monitoring is an important procedure to control the composting process. Due to cost limitation, temperature monitoring is manual and with daily sampling resolution. The objective of this study was to develop an automatic station with US$ 150 dollars, able to monitor air temperature at two different points in a compost pile, with a 5-min time resolution. In the calibration test, the sensors showed an estimated uncertainty from ± 1 to ± 1.9 ºC. In the field validation test, the station guaranteed secure autonomy for seven days and endured high humidity and extreme temperature (&gt; 70 °C).
DOI: 10.6084/m9.figshare.5669170.v1
title: Low-cost automatic station for compost temperature monitoring

description: ABSTRACT Temperature monitoring is an important procedure to control the composting process. Due to cost limitation, temperature monitoring is manual and with daily sampling resolution. The objective of this study was to develop an automatic station with US$ 150 dollars, able to monitor air temperature at two different points in a compost pile, with a 5-min time resolution. In the calibration test, the sensors showed an estimated uncertainty from ± 1 to ± 1.9 ºC. In the field validation test, the station guaranteed secure autonomy for seven days and endured high humidity and extreme temperature (&gt; 70 °C).
DOI: 10.6084/m9.figshare.5669164
title: Benign familial fleck retina: multimodal imaging including optical coherence tomography angiography

description: ABSTRACT This report presents multimodal imaging of a 27-year-old woman diagnosed with benign familial fleck retina (OMIM 228980), an uncommon disorder. Fundus photographs revealed retinal flecks that affected her post-equatorial retina but spared the macular area. Fundus autofluorescence and infrared imaging demonstrated a symmetrical pattern of yellow-white fleck lesions that affected both eyes. Her full-field electroretinogram and electrooculogram were normal. An optical coherence tomography B-scan was performed for both eyes, revealing increased thickness of the retinal pigmented epithelium leading to multiple small pigmented epithelium detachments. The outer retina remained intact in both eyes. Spectral-domain optical coherence tomography angiography with split-spectrum amplitude decorrelation algorithm and 3 × 3 mm structural en face optical coherence tomography did not show macular lesions. Benign familial fleck retina belongs to a heterogenous group of so-called flecked retina syndromes, and should be considered in patients with yellowish-white retinal lesions without involvement of the macula.
DOI: 10.6084/m9.figshare.5669164.v1
title: Benign familial fleck retina: multimodal imaging including optical coherence tomography angiography

description: ABSTRACT This report presents multimodal imaging of a 27-year-old woman diagnosed with benign familial fleck retina (OMIM 228980), an uncommon disorder. Fundus photographs revealed retinal flecks that affected her post-equatorial retina but spared the macular area. Fundus autofluorescence and infrared imaging demonstrated a symmetrical pattern of yellow-white fleck lesions that affected both eyes. Her full-field electroretinogram and electrooculogram were normal. An optical coherence tomography B-scan was performed for both eyes, revealing increased thickness of the retinal pigmented epithelium leading to multiple small pigmented epithelium detachments. The outer retina remained intact in both eyes. Spectral-domain optical coherence tomography angiography with split-spectrum amplitude decorrelation algorithm and 3 × 3 mm structural en face optical coherence tomography did not show macular lesions. Benign familial fleck retina belongs to a heterogenous group of so-called flecked retina syndromes, and should be considered in patients with yellowish-white retinal lesions without involvement of the macula.
DOI: 10.6084/m9.figshare.5669161
title: Pro-inflammatory Analysis of Macrophages in Contact with Titanium Particles and Porphyromonas gingivalis

description: Abstract During insertion of titanium dental implants, particles may shear from the implant to the periimplant region causing osteolysis, and their association with bacteria can exacerbate the inflammatory reaction. However, the association of a high invasive bacterium from the oral cavity, Porphyromonas gingivalis (Pg), and titanium particles remains unknown. This study evaluated pro-inflammatory reaction of human macrophages in contact with micro and nanoparticles of titanium associated with Porphyromonas gingivalis lipopolysaccharide (PgLPS). THP-1 cell were used and treated for 12, 24 and 48 h following 6 groups: Control(C), PgLPS (L); Microparticles (M); Nanoparticles (N); PgLPS and microparticles (LM); PgLPS and nanoparticles (LN). The following assays were carried out: i) cell viability using MTS, ii) cell morphology by SEM and iii) expression of tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β) and interleukin-6 (IL-6) by qRT-PCR and ELISA. For statistics two-way ANOVA followed by Tukey’s test was used (p&lt;0.05). After treatment, cells presented similar viability and morphology demonstrating that the treatments were not able to induce cell death. Gene expression was significantly higher for TNF-α and IL1-β after 12 h, and for IL-6 after 24 h in the N and LN groups. Cytokine production over time was an ascending curve for TNF-α with the peak at 48 h and IL1-β and IL-6 had a straight line among the time points, although cells from N group presented a significant production of IL-6 at 48 h. In conclusion, these results suggest that titanium nanoparticles stimulate stronger pro-inflammatory response in macrophages, independent of their association with LPS from P.gingivalis.