cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.14321716.v1
title: Tribological and mechanical properties of biobased reinforcement in a friction composite material

description: ABSTRACT This work presents the function of biobased ingredients (palm fiber) as reinforcement in brake pad materials. Reinforcement in brake lining improvise wear stability, wear resistance and friction optimization under a dynamic set of operating variables such as braking force, sliding speed, braking duration and braking temperature. The effect of palm fiber on physical, mechanical and tribological properties of brake pad composite is evaluated. The percentage of palm fiber is gradually increased from 2% to 12% at an interval of 2% as an alternate of rockwool fiber by varying the pressure and speed in a pin on disc tribometer. By increasing the pressure, 8% and 10% shows high friction stability at all speeds. The results show that the raise in the palm fiber quantity increases the hardness, specific gravity and heat swell and the properties, loss on ignition and porosity decreases. The SEM descriptions of the composite indicated that the smaller micro voids occurred in the sample having low palm fiber. Weight gain in the composites were also observed by exposing them in salt water, water and oil.
DOI: 10.6084/m9.figshare.14321716
title: Tribological and mechanical properties of biobased reinforcement in a friction composite material

description: ABSTRACT This work presents the function of biobased ingredients (palm fiber) as reinforcement in brake pad materials. Reinforcement in brake lining improvise wear stability, wear resistance and friction optimization under a dynamic set of operating variables such as braking force, sliding speed, braking duration and braking temperature. The effect of palm fiber on physical, mechanical and tribological properties of brake pad composite is evaluated. The percentage of palm fiber is gradually increased from 2% to 12% at an interval of 2% as an alternate of rockwool fiber by varying the pressure and speed in a pin on disc tribometer. By increasing the pressure, 8% and 10% shows high friction stability at all speeds. The results show that the raise in the palm fiber quantity increases the hardness, specific gravity and heat swell and the properties, loss on ignition and porosity decreases. The SEM descriptions of the composite indicated that the smaller micro voids occurred in the sample having low palm fiber. Weight gain in the composites were also observed by exposing them in salt water, water and oil.
DOI: 10.34703/gzx1-9v95/rbmfyx/hswk5w
title: ABC_delivery_method_case_studies_and_consensus_building.pdf

description: Final
DOI: 10.6084/m9.figshare.14321719
title: Hydroxylation of sunflower, corn and crambe oils and chemical characterization of the obtained vegetable polyols

description: ABSTRACT In this work, vegetable polyols were synthesized and characterization from sunflower’s, corn’s and crambe’s oils. The polyols were obtained from the chemical modification of the vegetable oils by the direct hydroxylation reaction with the peracid system in situ (formic acid and hydrogen peroxide) in the molar ratio (oil/acid/peroxide) of 1,0:3.0:1,5, temperature of 85 ºC, reaction time of 6 h with mechanical agitation. The products were characterized by viscosity, density, infrared spectroscopy (FTIR), hydroxyl number (IOH), iodine value (II) and acidity level (IA). The polyol with the best properties was obtained from sunflower oil, with IOH of 72.88 mg KOH/g of sample, II of 11.87 g I2/g sample, IA of 16.13 mg of NaOH/g sample and viscosity of 1096.4 mPa.s. The crambe polyol presented IOH of 40.80 mg KOH/g of sample, II of 78.18 g of I2/g sample, IA of 4.25 mg of NaOH/g of sample and viscosity of 649.9 mPa.s. Finally, the corn polyol presented IOH of 37.40 mg of KOH/g of sample, II of 62.47 g of I2/g of sample, IA of 54.62 mg of NaOH/g of sample and viscosity of 486.8 mPa.s. The application of the FTIR technique in the obtained polyols allowed the qualitative analysis of the hydroxyl groups by the appearance of a wide band in the range of 3400-3500cm-1, characteristic of this functional group. It was possible to synthesize the vegetable polyols from the hydroxylation reaction of the studied oils and the products have potential to be used in the synthesis of flexible polyurethanes, increasing the added value of the raw materials studied.
DOI: 10.6084/m9.figshare.14321719.v1
title: Hydroxylation of sunflower, corn and crambe oils and chemical characterization of the obtained vegetable polyols

description: ABSTRACT In this work, vegetable polyols were synthesized and characterization from sunflower’s, corn’s and crambe’s oils. The polyols were obtained from the chemical modification of the vegetable oils by the direct hydroxylation reaction with the peracid system in situ (formic acid and hydrogen peroxide) in the molar ratio (oil/acid/peroxide) of 1,0:3.0:1,5, temperature of 85 ºC, reaction time of 6 h with mechanical agitation. The products were characterized by viscosity, density, infrared spectroscopy (FTIR), hydroxyl number (IOH), iodine value (II) and acidity level (IA). The polyol with the best properties was obtained from sunflower oil, with IOH of 72.88 mg KOH/g of sample, II of 11.87 g I2/g sample, IA of 16.13 mg of NaOH/g sample and viscosity of 1096.4 mPa.s. The crambe polyol presented IOH of 40.80 mg KOH/g of sample, II of 78.18 g of I2/g sample, IA of 4.25 mg of NaOH/g of sample and viscosity of 649.9 mPa.s. Finally, the corn polyol presented IOH of 37.40 mg of KOH/g of sample, II of 62.47 g of I2/g of sample, IA of 54.62 mg of NaOH/g of sample and viscosity of 486.8 mPa.s. The application of the FTIR technique in the obtained polyols allowed the qualitative analysis of the hydroxyl groups by the appearance of a wide band in the range of 3400-3500cm-1, characteristic of this functional group. It was possible to synthesize the vegetable polyols from the hydroxylation reaction of the studied oils and the products have potential to be used in the synthesis of flexible polyurethanes, increasing the added value of the raw materials studied.
DOI: 10.34703/gzx1-9v95/rbmfyx/yx1i6y
title: ABC-UTC-GUIDE_Delivery-Methods.pdf

description: Guide
DOI: 10.34703/gzx1-9v95/rbmfyx
title: Delivery Methods for Accelerated Bridge Construction Projects: Case Studies and Consensus Building [ABC-UTC-2016-C1-ISU01]

description: Accelerated bridge construction (ABC) is a solution for upgrading substandard bridges that reduces construction and closure times and minimizes exposure of the traveling public and road workers to construction activities. To take full advantage of the benefits of ABC, agencies should decide which projects are appropriate for ABC and which procurement and project delivery methods to use. The research team compiled information on decision matrices for identifying ABC projects, alternative delivery methods, and the procurement methods used for ABC projects. Four ABC projects in three states (Georgia, Indiana, and Minnesota) were then investigated in detail. Note that this project coincides with a partner project that contained similar information collection efforts for bidding of ABC projects (Bidding of Accelerated Bridge Construction Projects: Case Studies and Consensus Building [ABCUTC-2016-C1-ISU02]). The research team reached out to personnel involved in the projects to discuss bid items, contracting methods, and lessons learned. The results of this effort are also included in four standalone case study summaries. The case studies suggest that ABC can be successfully implemented using any of the delivery methods explored in this study: design-build, design-bid-build, or construction manager/general contractor. Regardless of the project delivery method, communication and collaboration between the contractor and agency results in a better project outcome. Effective communication with the public is also important during ABC projects and can be done by either the agency or the contractor. After a project is completed, the agency can benefit from reviewing the lessons learned and successful aspects of the project and applying these to future projects. Final Presentation https://youtu.be/f6OKcQTHE_I
DOI: 10.6084/m9.figshare.14321721.v1
title: An experimental methodology to determine the parameters of the compression molding process of composite materials made of recycled thermoplastic and recovered wood

description: ABSTRACT The objective of this research is to determine the sintering process parameters of wood-plastic composite materials (WPC) manufactured by compression molding and with better properties from an engineering point of view. The structure of this article is, by itself, a proposal of experimental methodology to obtain WPC from recycled thermoplastic particles and recovered wood. This methodology includes the characterization of both starting materials and compression-molding tests, to determine in a first stage the temperature and time of sintering and, in a second stage, the content and size of the wood particles. Using recovered capirona wood (RCW) and recycled polypropylene (RPP); these parameters are evaluated by standardized tests on molded samples. For this case, the parameters are: 50 min of time into the oven at 190 °C, 30% and 70% in volume of RCW and RPP respectively and RCW particles from 0,98 mm to 1,90 mm of size.
DOI: 10.6084/m9.figshare.14321721
title: An experimental methodology to determine the parameters of the compression molding process of composite materials made of recycled thermoplastic and recovered wood

description: ABSTRACT The objective of this research is to determine the sintering process parameters of wood-plastic composite materials (WPC) manufactured by compression molding and with better properties from an engineering point of view. The structure of this article is, by itself, a proposal of experimental methodology to obtain WPC from recycled thermoplastic particles and recovered wood. This methodology includes the characterization of both starting materials and compression-molding tests, to determine in a first stage the temperature and time of sintering and, in a second stage, the content and size of the wood particles. Using recovered capirona wood (RCW) and recycled polypropylene (RPP); these parameters are evaluated by standardized tests on molded samples. For this case, the parameters are: 50 min of time into the oven at 190 °C, 30% and 70% in volume of RCW and RPP respectively and RCW particles from 0,98 mm to 1,90 mm of size.
DOI: 10.6084/m9.figshare.14321722
title: Influence of the molybdenum content in cobalt and molybdenum catalysts supported on magnesium oxide for the production of carbon nanotubes

description: ABSTRACT The development of carbon nanotubes production has been subject of research seeking higher carbon yields and selective processes towards materials with superior purity and quality. Among the methods for nanotube synthesis, the catalytic route is a viable option for large-scale production, since it allows a more effective control of reaction. CoMo/MgO catalysts with low loading of cobalt, 5 wt.%, and three different loading of molybdenum, 5, 10 and 20 wt.%, were prepared by incipient wetness impregnation for high yield and pure carbon nanotubes. A detailed characterization of the catalysts and nanotubes indicated a relationship between their properties. Catalysts prepared with higher molybdenum loading showed higher formation of MgMoO4 and CoMoO4 indicating an enhanced interaction of MgO and cobalt with molybdenum. Excess of molybdenum in the catalyst caused a decrease in carbon yield and produced nanotubes with a lower degree of graphitization.
DOI: 10.6084/m9.figshare.14321722.v1
title: Influence of the molybdenum content in cobalt and molybdenum catalysts supported on magnesium oxide for the production of carbon nanotubes

description: ABSTRACT The development of carbon nanotubes production has been subject of research seeking higher carbon yields and selective processes towards materials with superior purity and quality. Among the methods for nanotube synthesis, the catalytic route is a viable option for large-scale production, since it allows a more effective control of reaction. CoMo/MgO catalysts with low loading of cobalt, 5 wt.%, and three different loading of molybdenum, 5, 10 and 20 wt.%, were prepared by incipient wetness impregnation for high yield and pure carbon nanotubes. A detailed characterization of the catalysts and nanotubes indicated a relationship between their properties. Catalysts prepared with higher molybdenum loading showed higher formation of MgMoO4 and CoMoO4 indicating an enhanced interaction of MgO and cobalt with molybdenum. Excess of molybdenum in the catalyst caused a decrease in carbon yield and produced nanotubes with a lower degree of graphitization.
DOI: 10.6084/m9.figshare.14321724.v1
title: Ultra high molecular weight polyethylene doped with iron through high energy mechanical alloying

description: ABSTRACT Doping polymers with metallic materials can improve significantly its use. Ultra high molecular weight polyethylene is known for its high resistance to abrasion and impact, and also for its friction coefficient, which is significantly lower than that of commercial steel and most polymeric materials. Therefore, this material presents high industrial demand despite its processing difficulty due to its high viscosity. One kind of polymer processing which has been widely used recently is the high energy mechanical alloying. This method provokes significant changes in the material, such as crystalline structure transformation, amorphization, formation of metastable phases, and nanostructuring, among others. In order to investigate the influence of iron dopant in structural characteristics of polymeric matrix, ultra high molecular weight polyethylene were doped with low concentrations (between 0.1 at.% and 1 at.%) of iron using the method of high energy mechanical alloying. The samples composition was characterized by X-Ray Diffraction Mössbauer Spectroscopy. A theoretical molecular modeling was carried out to simulate the iron presence in polymeric cell, which is in good agreement with the experimental results. Therefore, there is evidence that part of the iron promotes a crossed bond between the polymeric chains.
DOI: 10.6084/m9.figshare.14321724
title: Ultra high molecular weight polyethylene doped with iron through high energy mechanical alloying

description: ABSTRACT Doping polymers with metallic materials can improve significantly its use. Ultra high molecular weight polyethylene is known for its high resistance to abrasion and impact, and also for its friction coefficient, which is significantly lower than that of commercial steel and most polymeric materials. Therefore, this material presents high industrial demand despite its processing difficulty due to its high viscosity. One kind of polymer processing which has been widely used recently is the high energy mechanical alloying. This method provokes significant changes in the material, such as crystalline structure transformation, amorphization, formation of metastable phases, and nanostructuring, among others. In order to investigate the influence of iron dopant in structural characteristics of polymeric matrix, ultra high molecular weight polyethylene were doped with low concentrations (between 0.1 at.% and 1 at.%) of iron using the method of high energy mechanical alloying. The samples composition was characterized by X-Ray Diffraction Mössbauer Spectroscopy. A theoretical molecular modeling was carried out to simulate the iron presence in polymeric cell, which is in good agreement with the experimental results. Therefore, there is evidence that part of the iron promotes a crossed bond between the polymeric chains.
DOI: 10.6084/m9.figshare.14321725
title: Multi-scale analysis of the two-dimensional problem of plates submitted to shear loadings and considering phase debonding

description: ABSTRACT The present work deals with numerical analyses on mechanical behavior of ductile microstructures reinforced by elastic inclusions and the consequences upon micromechanical behavior of structures submitted to shear loadings. For this proposal, a proposed modeling based on computational homogenization technique using full coupling between scales and BEM/FEM is used. Also, the phase debonding is taken into account by using cohesive fracture and contact models where the opening sliding phenomenon is considered. On the other hand, the ductility of the metallic matrix is represented by Von Mises model. Initially, the numerical analyses are performed only at microstructural level and then a full coupled multi-scale analysis of a plate is considered, showing coherence between the micro and macro scale results.
DOI: 10.6084/m9.figshare.14321725.v1
title: Multi-scale analysis of the two-dimensional problem of plates submitted to shear loadings and considering phase debonding

description: ABSTRACT The present work deals with numerical analyses on mechanical behavior of ductile microstructures reinforced by elastic inclusions and the consequences upon micromechanical behavior of structures submitted to shear loadings. For this proposal, a proposed modeling based on computational homogenization technique using full coupling between scales and BEM/FEM is used. Also, the phase debonding is taken into account by using cohesive fracture and contact models where the opening sliding phenomenon is considered. On the other hand, the ductility of the metallic matrix is represented by Von Mises model. Initially, the numerical analyses are performed only at microstructural level and then a full coupled multi-scale analysis of a plate is considered, showing coherence between the micro and macro scale results.
DOI: 10.6084/m9.figshare.14321727
title: Blends rheological properties of copolymer polypropylene/recycled polypropylene from industrial containers

description: ABSTRACT In this study, blends of copolymer polypropylene (PPCop /recycled polypropylene (PPRec) from industrial containers after consumption were evaluated in three different ratios (80:20, 60:40 and 40:60 wt.%). The blends were evaluated by melt flow index, torque rheometry and rheology in a dynamic oscillatory regime. The results from the melt flow index indicated that the blending of recycled material with PPCop causes a decrease in the molecular weight as compared to PPCop. By torque rheometry, it was verified that the blends showed improved processability in relation to PPCop. Also, the blends showed stability throughout the processing, indicating absence of degradation due to the process conditions used. By the dynamic-oscillatory regime tests, it was observed that, at low frequencies (&lt;1 rad/s), the PPCop and the blends (PPCop / PPRec) demonstrated a Newtonian fluid behavior, whereas, at frequencies greater than 1 rad/s, a pseudoplastic fluid behavior was observed. The values of the intersection points (G ‘= G”) of the storage modulus curves (G’) and loss modulus (G’), as a function of the angular frequency (ω) indicated that the blends showed a reduction of the molecular weight, which was more pronounced in the composition containing 60% PPRec. The rheological results of the PPCop / PPRec blends were of great relevance, since they allowed the analysis of the blends behavior containing recycled material.
DOI: 10.6084/m9.figshare.14321728
title: Light-Curing Units, Photoinitiators System, and Monomers on Physico-Mechanical Properties of Experimental Composite Resins

description: ABSTRACT This study evaluated the physico-mechanical properties of experimental composite resins made with different resin matrix and light-curing units. Experimental composite groups were divided according to monomers (BisGMA + TEGDMA-BT and BisGMA + BisEMA + UDMA + TEGDMA-BBUT) and photoinitiator system (camphorquinone-CQ and 1-phenyl-1,2-propanedione-PPD). A quartz tungsten halogen (QTH) or light-emitting diode (LED) were used to light cure all materials. Knoop microhardness (n = 10) was determined using Knoop microhardness test. Compressive strength, diametral tensile strength, and Young modulus (n = 7) were obtained using a universal testing machine at crosshead speed of 1.0 mm/min. The data were submitted to a three-way ANOVA and the Tukey post-hoc test (α = 0.05). QTH presented the highest total irradiance values and similar total radiant exposure to LED. For the compressive strength test, BT-PPD light-cured with LED group showed the lowest mean value. BT-CQ light-cured with LED group exhibited the lowest diametral tensile strength results. The BBUT-composite resins presented lowest Young modulus values, with no statistical difference between light-curing units (QTH and LED) and photoinitiators system (CQ and PPD). Application of QTH or LED in BT-based composite resins with PPD photoinitiator generated suitable results regarding the physico-mechanical properties.
DOI: 10.6084/m9.figshare.14321731.v1
title: Evaluation of physical properties of six forest wood species

description: ABSTRACT This study aims at assessing and correlating physical properties of wood, such as basic specific mass, moisture content, water absorption, loss of mass at 50 ° C and 100 ° C, maximum linear contraction (β), coefficient of contraction anisotropy (Ca β), maximum linear swelling (α) and coefficient of swelling anisotropy (Caα), being analyzed for wood of the following species: Corymbia citriodora, Corymbia maculata, Eucalyptus dunnii, Eucalyptus grandis, Eucalyptus saligna and Eucalyptus tereticornis. For that, 20 mm x 20 mm x 15 mm specimens were prepared. For the physical analyzes, the specimens were submerged in water until saturated, conditioned at a temperature of 20 ° C with relative humidity (RH) of 65% and oven dried (100 ± 3 ° C). Mass data and dimensions of these specimens were collected in each of these stages, for later calculation of the technological properties. It was observed that the wood of the seven species presented significant difference. Analyzing the mass loss properties at 100 ° C and basic specific mass, as well as anisotropy for swelling (Ca α) and contraction (Caβ), they present a significant correlation, being directly proportional. The basic specific mass and water absorption, loss of mass at 100 ° C and water absorption, Coefficient of Contraction Anisotropy (Caβ) and water absorption, showed significant correlations, being these inversely proportional properties. The wood of the genus Corymbia presented average values of technological properties superior to those of the genus Eucalyptus, highlighting the wood Corymbia citriodora.