cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.9870689.v1
title: Evaluation of the effect of compatibilizing agent (PP-g-MA) on PP/Thermoplastic starch blends

description: ABSTRACT The growing waste of plastics in the environment coupled with concerns about future oil shortages has increased interest in biodegradable polymers such as starch. In recent years, starch has been used in blends with different synthetic polymers. Such blends have been compatibilized by the use of compatibilizing agents of the copolymer type. In this study, the morphological, mechanical and thermal properties of polypropylene (PP)/thermoplastic starch (TPS) blends obtained in the presence of the compatibilizing agent (PP-g-MA) were evaluated. The thermoplastic starch was obtained in a single screw extruder with 20% (mass/mass) of glycerol used as plasticizer. PP/TPS blends were prepared by melt mixing in a co-rotating twin-screw extruder. The concentration of the compatibilizing agent was 3, 5 and 7% (mass/mass). The morphology of the blends was evaluated by scanning electron microscopy. The results showed a significant reduction of the dispersed starch phase with the addition of the PP-g-MA. The blends obtained in the presence of PP-g-MA showed a more homogeneous distribution of the starch phase in the PP matrix. The results obtained with the tensile tests showed that the elastic modulus of PP undergoes a slight increase with the addition of the starch and the compatibilizer. The tensile strength of the PP was not significantly affected. However, there was a significant decrease of the elongation at break with the incorporation of starch. The starch incorporated in the PP matrix led to a significant increase in the impact strength of the final material. However, with the addition of PP-g-MA to the PP/TPS blend, the impact strength falls. This result can be attributed to the reduction of the starch phase in the PP matrix. The thermal stability of the PP/TPS blends was slightly increased with the incorporation of the compatibilizing agent. The materials obtained can be used instead of PP.
DOI: 10.6084/m9.figshare.9870665
title: Preparation, characterization and catalytic evaluation of Fe2O3/graphite composite in photo-Fenton reaction

description: ABSTRACT In this work, Fe2O3/graphite composite was prepared and used as a catalyst in photo-Fenton reaction for the decolorization of amaranth dye from aqueous solution under visible light irradiation. Samples with different Fe2O3 contents supported on graphite were prepared and characterized by X-ray diffraction (XRD), N2 adsorption-desorption and scanning electron microscopy (SEM). The increase of the iron content in the composites resulted in a superior specific surface area. The response surface methodology generated from the Rotational Central Composite Design (RCCD) showed a maximum efficiency in the decolorization of the dye solution of 93% under the optimal experimental conditions of photo-Fenton reaction (pH = 2.5, amount of catalyst = 0.35 g L-1 and molar ratio H2O2/Ʃ mineralizable compounds: 4.7). Therefore, the Fe2O3/graphite composite can be used as a potential photo-Fenton catalyst for the degradation of amaranth dye from liquid effluents.
DOI: 10.6084/m9.figshare.9870668
title: Characterization of acai waste particles for civil construction use

description: ABSTRACT In the Amazon, the main potential for contributing to the Sustainable Development Goals (SDG) lies in using agro industry waste in civil construction as an alternative for sustainable materials. In this context, this study aimed to assess the potential use of acai (Euterpe oleracea and Euterpe precatoria) waste particles to create composites that may be used in more sustainable buildings. Density assays were performed using picnometry. The moisture levels were measured and, lignin, cellulose and extractive contents were assessed according to the parameters of TAPPI 204, 211, and 222. Density analyses were performed using picnometry, moisture was analyzed, and lignin, cellulose, and extractive contents were assessed according to the parameters of TAPPI 204, 211, and 222. The results showed that the mean particle density is 1.49 g.cm-3 and the moisture content ranged from 2 to 6%. Regarding chemical make-up, higher lignin and extractive contents were found, in addition to a reduction in cellulose compared to other plant fibers. Scanning electron microscopy (SEM) revealed the presence of only the endocarp of açaí stone in particles of 8 and 14 Tyler and a higher prevalence of fibers in particles of 48, 100, and 200 Tyler. Knowing the characteristics and behaviors of açaí waste particles is important to lay basis for composite processing stages using this material. Moreover, the use of acai stones reduce the environmental impacts, allowing mainly civil construction to produce new, more ecological materials that lead to sustainability indicators in buildings of the Amazon.
DOI: 10.6084/m9.figshare.9870674
title: Comparative study of PES/CO knitted fabrics dyeing with water treated with vegetable oil clarification residue, in natural and calcined form

description: ABSTRACT The textile industry uses a large volume of water, which makes it necessary to find more sustainable options for its use, such as reuse in new dyeing. The use of a solid industrial waste as an adsorbent may be an alternative to treat the textile effluent. The objective of this study was to test the viability of the reuse of dispersed dye solution, treated with residue of the clarification of vegetable oil as an alternative adsorbent, in polyester/cotton (PES/CO 50/50) knitted fabrics dyeing. Two types of pre-treatment were used in the adsorbent, natural (RC) dried at 70°C for 24h and calcined (RCc) at 600°C for 2h30min. Dyeing was performed with the solution treated at 100%, 75% and 50% (v/v) concentrations and in light colors, the pattern was dyed with water from the textile industry. UV-Vis spectrophotometry was used to evaluate the efficiency of the treatment and the evaluation of the red tissues by dyeing parameters: exhaustion (%) by UV-Vis spectrophotometry; K/S, relative strength (SR%) and DE by remission spectrophotometry, as well as color fastness to washing and friction . The treatment efficiency was 91,26% for RC residue, and 95,38% for RCc. Values ranged from 80% to 92% for PES and 70% to 85% for CO. The DE ranged from 0,22 to 1,2, with most values falling into the range accepted by industry (DE≤1,0). There was no great variation for K/S and SR (%) values, with the greatest variation of 0,09 units for K/S and 7,2% for SR (%). The color fastness showed grades between 4/5 and 5 on the gray scales, indicating that there is no migration of the dye. The proposal of treatment and reuse of the solution in new dyeing showed as a viable alternative when compared
DOI: 10.6084/m9.figshare.9870677.v1
title: Evaluation of different factors in the removal of remazol brilliant blue from aqueous solutions by adsorption in sugarcane and green coconut fibers

description: ABSTRACT The textile industries, during the dyeing process, release a large amount of dyes in the water. In addition to its visual effect and its adverse impacts on photosynthesis and chemical oxygen demand, many synthetic dyes are toxic, recalcitrant, mutagenic and carcinogenic. In this way, new alternatives of treatment of the generated effluents, less aggressive to the environment, of low cost and renewable have been sought, as the use of lignocellulosic agricultural residues, like dyes adsorbents. In this study, sugar cane and coconut fibers were studied for their ability to adsorb Remazol Brilliant Blue BB dye, and the effects of time, pH, amount of adsorbent material and dye concentration on dye adsorption were investigated. The optimal adsorption time was 24 h for coconut fiber and 12 h for sugar cane fiber. For both fibers, the optimal pH for the adsorption of dye was 2, and the use of 20 g L-1 of fiber was the most effective for removing 50-200 mg L-1 of Remazol Brilliant Blue BB, with adsorption percentages of above 90.50% observed for both fibers.
DOI: 10.6084/m9.figshare.9870662
title: Assessment of coconut fibers for textile applications

description: ABSTRACT Brazil is the fourth larger producer in coconut fruit in the world. However, the industry processes only a small portion of coconut byproducts, which have caused serious environmental problems. The purpose of this article is to test an alternative for the recovery of coconut byproduct. In a series of experiments, recovered coconut fibers (coir) were treated to be employ in textile application. After initial classification and sampling, the fine coconut fibers were subjected to a simultaneous scouring and pre-bleaching process in a mild alkali solution together with hydrogen peroxide (H2O2). The fibers were first subjected to this treatment for 10 minutes at 80°C and then again for 20 minutes at the boiling point. The samples were then treated with a cationic softener for 10 minutes at 60°C. After this process, the physical and mechanical properties were measured and values proved not to be statistically significant. The article indicates some of the main obstacles when handling coconut fiber for textile applications and reveals that besides elongation, softness and homogeneity are essential for coconut fibers spinning. Findings in this investigation showed some improved results in relation to the previous literature in two aspects: Firstly, because the treatment did not harm the fibers quality; secondly, because due to the treatment the coconut fibers could be arranged in fibrous strands, which facilitated spinning and weaving for use in textile applications.
DOI: 10.6084/m9.figshare.9870665.v1
title: Preparation, characterization and catalytic evaluation of Fe2O3/graphite composite in photo-Fenton reaction

description: ABSTRACT In this work, Fe2O3/graphite composite was prepared and used as a catalyst in photo-Fenton reaction for the decolorization of amaranth dye from aqueous solution under visible light irradiation. Samples with different Fe2O3 contents supported on graphite were prepared and characterized by X-ray diffraction (XRD), N2 adsorption-desorption and scanning electron microscopy (SEM). The increase of the iron content in the composites resulted in a superior specific surface area. The response surface methodology generated from the Rotational Central Composite Design (RCCD) showed a maximum efficiency in the decolorization of the dye solution of 93% under the optimal experimental conditions of photo-Fenton reaction (pH = 2.5, amount of catalyst = 0.35 g L-1 and molar ratio H2O2/Ʃ mineralizable compounds: 4.7). Therefore, the Fe2O3/graphite composite can be used as a potential photo-Fenton catalyst for the degradation of amaranth dye from liquid effluents.
DOI: 10.6084/m9.figshare.9870668.v1
title: Characterization of acai waste particles for civil construction use

description: ABSTRACT In the Amazon, the main potential for contributing to the Sustainable Development Goals (SDG) lies in using agro industry waste in civil construction as an alternative for sustainable materials. In this context, this study aimed to assess the potential use of acai (Euterpe oleracea and Euterpe precatoria) waste particles to create composites that may be used in more sustainable buildings. Density assays were performed using picnometry. The moisture levels were measured and, lignin, cellulose and extractive contents were assessed according to the parameters of TAPPI 204, 211, and 222. Density analyses were performed using picnometry, moisture was analyzed, and lignin, cellulose, and extractive contents were assessed according to the parameters of TAPPI 204, 211, and 222. The results showed that the mean particle density is 1.49 g.cm-3 and the moisture content ranged from 2 to 6%. Regarding chemical make-up, higher lignin and extractive contents were found, in addition to a reduction in cellulose compared to other plant fibers. Scanning electron microscopy (SEM) revealed the presence of only the endocarp of açaí stone in particles of 8 and 14 Tyler and a higher prevalence of fibers in particles of 48, 100, and 200 Tyler. Knowing the characteristics and behaviors of açaí waste particles is important to lay basis for composite processing stages using this material. Moreover, the use of acai stones reduce the environmental impacts, allowing mainly civil construction to produce new, more ecological materials that lead to sustainability indicators in buildings of the Amazon.
DOI: 10.6084/m9.figshare.9870674.v1
title: Comparative study of PES/CO knitted fabrics dyeing with water treated with vegetable oil clarification residue, in natural and calcined form

description: ABSTRACT The textile industry uses a large volume of water, which makes it necessary to find more sustainable options for its use, such as reuse in new dyeing. The use of a solid industrial waste as an adsorbent may be an alternative to treat the textile effluent. The objective of this study was to test the viability of the reuse of dispersed dye solution, treated with residue of the clarification of vegetable oil as an alternative adsorbent, in polyester/cotton (PES/CO 50/50) knitted fabrics dyeing. Two types of pre-treatment were used in the adsorbent, natural (RC) dried at 70°C for 24h and calcined (RCc) at 600°C for 2h30min. Dyeing was performed with the solution treated at 100%, 75% and 50% (v/v) concentrations and in light colors, the pattern was dyed with water from the textile industry. UV-Vis spectrophotometry was used to evaluate the efficiency of the treatment and the evaluation of the red tissues by dyeing parameters: exhaustion (%) by UV-Vis spectrophotometry; K/S, relative strength (SR%) and DE by remission spectrophotometry, as well as color fastness to washing and friction . The treatment efficiency was 91,26% for RC residue, and 95,38% for RCc. Values ranged from 80% to 92% for PES and 70% to 85% for CO. The DE ranged from 0,22 to 1,2, with most values falling into the range accepted by industry (DE≤1,0). There was no great variation for K/S and SR (%) values, with the greatest variation of 0,09 units for K/S and 7,2% for SR (%). The color fastness showed grades between 4/5 and 5 on the gray scales, indicating that there is no migration of the dye. The proposal of treatment and reuse of the solution in new dyeing showed as a viable alternative when compared
DOI: 10.6084/m9.figshare.9870659
title: Extraction and evaluation of tannin from green coconut mesocarp

description: ABSTRACT The development of alternatives for reuse of coconut shell allows inadequate solid residues disposal reduction and provides a novelty option close to the production sites. This paper aims to evaluate the tannin extraction potential of the green coconut mesocarp, as well as its adhesive capacity. Tannin extraction was performed with sodium sulfite diluted in water at 0%, 1%, 5% and 8% concentrations. It was observed which extraction resulted in better yield and characteristics to be used as an adhesive agent. The concentration of sodium sulfite at 5% allowed higher yields of tannin extraction. When compared to phenol formaldehyde, the tannin had similar adhesive characteristics such as 153.84 cp viscosity and 54.57% solid content. For the FT-IR spectroscopy analysis, dry samples of the coconut mesocarp were used. The peaks observed in the infrared spectrum of the green coconut mesocarp are characteristic of tannins found in biomass, presenting desirable chemical characteristics to be used as an adhesive agent. The coconut mesocarp is a material with potential for tannin extraction, making it suitable to be used in the gluing of panels.
DOI: 10.6084/m9.figshare.9870671.v1
title: Evaluation of the post cure use on the thermal and mechanical properties of a room temperature curing epoxy system

description: ABSTRACT In this work, a room temperature curing epoxy system was submitted to post cure cycles to evaluate the thermal and mechanical properties of the material. The samples were obtained by casting into a metallic tool and the post cure cycles were performed at 75°C, 90°C, 110°C for one hour and at 110°C cycle for 2 hours. The differential scanning calorimetry (DSC) results showed that the glass transition temperature of the material have not change significantly with the post cure cycles, which indicates a number of molecular crosslinks very similar to the original sample, without post cure. The thermogravimetric (TGA) results revealed a stepwise thermal degradation; where about 70% mass of the material undergoes thermal degradation in the temperature range from 330.9°C to 345.1°C. The temperature-time transformation (TTT) diagram of a thermoset polymer was used to understand the cure kinetics, where it was suggested that the amount of resin and curing agent had a more significant influence on the full curing of the sample than the post cure cycles carried out in this article. By means of mechanical properties, the hardness of the material remained unchanged with the post curing cycles. Only one batch obtained lower values of hardness because the excess of curing agent worked as plasticizing agent. O In terms of elastic modulus, the free-beam method presented values between 1.72GPa and 2.18GPa, and the post cure cycles did not have any notable influence on this property.
DOI: 10.6084/m9.figshare.9870650
title: Experimental study of the influence of the addition of polypropylene microfibers and cure on the surface hardness of concrete floors

description: ABSTRACT Failures of dosing and execution of concrete floors, constantly lead to the emergence of pathological manifestations. Therefore, it is indispensable to know the factors that influence the behavior of the concrete or alter its characteristics, as well as the use of quality manpower. This study evaluated the influence of the addition of polypropylene microfibers in the contents of 0 g/m3, 600 g/m3 and 900 g/m3 and of different curing conditions (without cure, wet cure and wet cure after three days of exposure) in concrete used in floors. For that, tests of bleeding, compressive strength and surface hardness by rebound hammer were per-formed. The results indicate that the use of microfibers significantly influenced the bleeding and the compressive strength, although the surface hardness was not affected directly by this material nor by the type of cure. In general, it can be said that of the polypropylene microfiber contents evaluated, the 600 g/m3 content is the most suitable for addition in the concrete, presenting better performance in the analyzed properties. It is possible to affirm still that the cure, although not having caused significant influence on the surface of the concrete, is a factor of extreme importance for its mass properties.
DOI: 10.6084/m9.figshare.9870653
title: Reconstruction of the Late Pleistocene to Late Holocene vegetation transition using packrat midden and pollen evidence from the Central Mojave Desert

description: ABSTRACT The Mojave Desert of the American West is characterized by plant species that reflect a unique mixture of winter precipitation and summer monsoon climate. Currently, the Mojave Desert experiences a strong summer monsoonal pattern with weak winter precipitation. Data from pollen and packrat midden analyses have revealed a history of Mojave Desert vegetation during the transition from the late Pleistocene to late Holocene (~17500 Cal. years B.P. to ~ 1200 Cal. years B.P.) that highlight a summer dominated monsoonal pattern, similar to those in the greater American Southwest. We compare pollen data from a lava tube in the Cima volcanic field, located in south-central region of the Mojave Desert, with plant macrofossil data from several woodrat midden localities in the region. The record for the Cima volcanic field reveals a vegetation history spanning the last ~ 8300 Cal. years B.P., with data from ancient woodrat middens detailing the record from ~17500 Cal. years B.P. to 7,800 Cal. years B.P. A Bryson macro-physical climate model for the transition from the late Pleistocene to the Late Holocene was created and compared to our findings to assess possible relationships between climatic variations and the arrival of diagnostic plant species within the Mojave Desert.
DOI: 10.6084/m9.figshare.9870656
title: Genetic diversity and nonparametric statistics to identify possible ISSR marker association with fiber quality of pineapple

description: Abstract: Due to the increasing search for renewable resources, plant fibers have become an alternative when creating new products. Studies demonstrate the potential use of pineapple fibers in composites. The objective of this work was to evaluate the genetic diversity and verify any association between ISSR (Inter Simple Sequence Repeats) bands and quality of pineapple fibers for use in cements in the civil construction. The study analyzed the genetic variability of 11 pineapple genotypes, as well as the possible association of 131 bands from 16 ISSR markers with fiber quality characteristics. Eleven bands were selected based on their high correlations (0.64578* to 0.72457*) with three fiber quality variables. Of these, two bands were purified, sequenced, and blasted against sequences in GenBank at NCBI. These markers can be used in marker assisted selection to genetically improve the quality of pineapple fiber. Bands that returned no hits in the NCBI BLAST search can be deposited as new sequences in the GenBank. Therefore, the SCAR markers, once validated, can be useful in pineapple genetic breeding programs worldwide by using molecular marker assisted selection for fiber resistance, which could subsidize the development of more promising genotypes for industrial use and contribute to the sustainability of this new production sector.
DOI: 10.6084/m9.figshare.9870662.v1
title: Assessment of coconut fibers for textile applications

description: ABSTRACT Brazil is the fourth larger producer in coconut fruit in the world. However, the industry processes only a small portion of coconut byproducts, which have caused serious environmental problems. The purpose of this article is to test an alternative for the recovery of coconut byproduct. In a series of experiments, recovered coconut fibers (coir) were treated to be employ in textile application. After initial classification and sampling, the fine coconut fibers were subjected to a simultaneous scouring and pre-bleaching process in a mild alkali solution together with hydrogen peroxide (H2O2). The fibers were first subjected to this treatment for 10 minutes at 80°C and then again for 20 minutes at the boiling point. The samples were then treated with a cationic softener for 10 minutes at 60°C. After this process, the physical and mechanical properties were measured and values proved not to be statistically significant. The article indicates some of the main obstacles when handling coconut fiber for textile applications and reveals that besides elongation, softness and homogeneity are essential for coconut fibers spinning. Findings in this investigation showed some improved results in relation to the previous literature in two aspects: Firstly, because the treatment did not harm the fibers quality; secondly, because due to the treatment the coconut fibers could be arranged in fibrous strands, which facilitated spinning and weaving for use in textile applications.