cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.12094965
title: Preparation of porous brick using MDF residues in the formulation of structural ceramic masses

description: ABSTRACT MDF industrial wastes (Medium Density Fiberboard) generated in the wood furniture industries, have been causing serious environmental impacts, since their improperly disponishment in the nature. In light of this, the purpose of this work is to develop new structural ceramic compositions, containing 5, 10 and 15% by mass of MDF waste. The mineralogical, chemical and thermal characteristics of the masses were analyzed. Test bodies (50mm x15mm x 5mm) were shaped by uniaxial press (13.3 MPa), which were dried at 110º C/24h and sintered at 750, 850 and 950 °C. Subsequently, these were subjected to the following characterizations: Water absorption, apparent density, apparent porosity and flexion rupture module. The mineralogical and microstructural characteristics, after firing, were also analyzed. The results showed that up to 10% of the residue of MDF in the form of powder could be incorporated into structural ceramic masses for the productions of ceramic materials, such as acoustic and thermal insulation porous bricks. The apparent porosity was 31.7 %, bulk density was 1.6 g/cm3, the flexural strength was 11.5 MPa.
DOI: 10.6084/m9.figshare.12094965.v1
title: Preparation of porous brick using MDF residues in the formulation of structural ceramic masses

description: ABSTRACT MDF industrial wastes (Medium Density Fiberboard) generated in the wood furniture industries, have been causing serious environmental impacts, since their improperly disponishment in the nature. In light of this, the purpose of this work is to develop new structural ceramic compositions, containing 5, 10 and 15% by mass of MDF waste. The mineralogical, chemical and thermal characteristics of the masses were analyzed. Test bodies (50mm x15mm x 5mm) were shaped by uniaxial press (13.3 MPa), which were dried at 110º C/24h and sintered at 750, 850 and 950 °C. Subsequently, these were subjected to the following characterizations: Water absorption, apparent density, apparent porosity and flexion rupture module. The mineralogical and microstructural characteristics, after firing, were also analyzed. The results showed that up to 10% of the residue of MDF in the form of powder could be incorporated into structural ceramic masses for the productions of ceramic materials, such as acoustic and thermal insulation porous bricks. The apparent porosity was 31.7 %, bulk density was 1.6 g/cm3, the flexural strength was 11.5 MPa.
DOI: 10.6084/m9.figshare.12094971
title: Characterization and Physical, Chemical and Mechanical Properties of the Kaolinitic Clays of the Northeast Region of Pará State

description: ABSTRACT This work was developed to study the behavior of two types of clays from São Miguel do Guamá-Pará region (northern Brazil) from a series of clay. Mixed and unmixed formulations of Strong and Weak Clay were tested. The raw materials were subjected to XRD, XFR, SEM and screening and sedimentation tests. It was elaborated the test components were pressed uniaxially in rectangular metal matrix. Physical and systematic properties were: Water absorption, apparent porosity, apparent mass production, linear firing shrinkage and flexural strength at three points. The microstructure of the ceramics was evaluated by SEM and XRD. The values presented as clays have favorable characteristics for the production of sealing blocks, showing that the best combination was a 30% strong clay (M4) mixture.
DOI: 10.6084/m9.figshare.12094971.v1
title: Characterization and Physical, Chemical and Mechanical Properties of the Kaolinitic Clays of the Northeast Region of Pará State

description: ABSTRACT This work was developed to study the behavior of two types of clays from São Miguel do Guamá-Pará region (northern Brazil) from a series of clay. Mixed and unmixed formulations of Strong and Weak Clay were tested. The raw materials were subjected to XRD, XFR, SEM and screening and sedimentation tests. It was elaborated the test components were pressed uniaxially in rectangular metal matrix. Physical and systematic properties were: Water absorption, apparent porosity, apparent mass production, linear firing shrinkage and flexural strength at three points. The microstructure of the ceramics was evaluated by SEM and XRD. The values presented as clays have favorable characteristics for the production of sealing blocks, showing that the best combination was a 30% strong clay (M4) mixture.
DOI: 10.6084/m9.figshare.12095013.v1
title: The influence of temperature on phase transformations of the minerals present in the red mud: reduction of hematite to magnetite

description: ABSTRACT In this work a technological route was proposed to analyze the behavior of phase transformations of the minerals present in the red mud during the process of reduction of hematite to magnetite. The fluorescence analysis and X-ray diffraction showed that red mud presented approximately 5% titanium oxide as anatase and 28% iron oxide in the forms of hematite and goethite. Experiments involving the reduction of hematite to magnetite using thermal treatment. The material was calcined at temperatures of 500, 600 and 1000 °C for 2 h. Then, X-ray diffraction and Raman spectroscopy analyzes were performed, which showed that the hematite was reduced to magnetite in all experimental conditions. For the calcination temperatures of 500 and 600 °C, the titanium oxide remained in anatase free form, but for the calcination performed at 1000 ºC, the oxide passed into the form combined with iron (ilmenite). The route proposed in this work allowed to obtain a material with magnetic characteristics, which could be used as source of titanium after extraction of iron compounds by magnetic separation or acid leaching.
DOI: 10.6084/m9.figshare.12095013
title: The influence of temperature on phase transformations of the minerals present in the red mud: reduction of hematite to magnetite

description: ABSTRACT In this work a technological route was proposed to analyze the behavior of phase transformations of the minerals present in the red mud during the process of reduction of hematite to magnetite. The fluorescence analysis and X-ray diffraction showed that red mud presented approximately 5% titanium oxide as anatase and 28% iron oxide in the forms of hematite and goethite. Experiments involving the reduction of hematite to magnetite using thermal treatment. The material was calcined at temperatures of 500, 600 and 1000 °C for 2 h. Then, X-ray diffraction and Raman spectroscopy analyzes were performed, which showed that the hematite was reduced to magnetite in all experimental conditions. For the calcination temperatures of 500 and 600 °C, the titanium oxide remained in anatase free form, but for the calcination performed at 1000 ºC, the oxide passed into the form combined with iron (ilmenite). The route proposed in this work allowed to obtain a material with magnetic characteristics, which could be used as source of titanium after extraction of iron compounds by magnetic separation or acid leaching.
DOI: 10.6084/m9.figshare.12095022.v1
title: Use of Bauxite Washout Reagent for the Manufacture of Geopolymer Binders

description: ABSTRACT The negative reality of environmental impacts has made society look for less aggressive alternatives to the environment. The productive chains of large companies, unfortunately, generate waste or tailings that contribute to this reality that has become the focus of discussion. This environmental issue becomes extremely important for the society of the state of Pará, since it has great mining potential focused on aluminum production, for example, and naturally by its process, produces waste and tailings that are deposited in form of large ponds. Aiming to make a positive contribution to society and the environment, we chose to use bauxite washing tailings as a source of aluminosilicates for the production of geopolymers that are three-dimensional cementitious materials formed by alkaline activation. Therefore, this research aims to verify the possibility of transforming bauxite tailings into a geopolymeric binder of mechanical strength equivalent to Portland cement. With Davidovits ratio (SiO2/Al2O3) of 0.81 and 0.82 for the respective calcination temperatures at 600°C and 700°C, pressure tests were evaluated for 3 and 10 days of cure. The geopolymerization reaction was conducted at room temperature of 28°C using as activators 15 molar sodium hydroxide and 10 molar alkaline sodium silicate. XRD, XRF, SEM, particle size analysis, TG and DTA techniques were used to characterize the raw materials and geopolymers. The best geopolymer was calcined raw material at 700°C, Davidovits highest ratio 0.82, presenting fresh workability and greater mechanical compressive strength above 10.0MPa for 3 days when compared to the standards for CP II E 32 type cement.
DOI: 10.6084/m9.figshare.12095022
title: Use of Bauxite Washout Reagent for the Manufacture of Geopolymer Binders

description: ABSTRACT The negative reality of environmental impacts has made society look for less aggressive alternatives to the environment. The productive chains of large companies, unfortunately, generate waste or tailings that contribute to this reality that has become the focus of discussion. This environmental issue becomes extremely important for the society of the state of Pará, since it has great mining potential focused on aluminum production, for example, and naturally by its process, produces waste and tailings that are deposited in form of large ponds. Aiming to make a positive contribution to society and the environment, we chose to use bauxite washing tailings as a source of aluminosilicates for the production of geopolymers that are three-dimensional cementitious materials formed by alkaline activation. Therefore, this research aims to verify the possibility of transforming bauxite tailings into a geopolymeric binder of mechanical strength equivalent to Portland cement. With Davidovits ratio (SiO2/Al2O3) of 0.81 and 0.82 for the respective calcination temperatures at 600°C and 700°C, pressure tests were evaluated for 3 and 10 days of cure. The geopolymerization reaction was conducted at room temperature of 28°C using as activators 15 molar sodium hydroxide and 10 molar alkaline sodium silicate. XRD, XRF, SEM, particle size analysis, TG and DTA techniques were used to characterize the raw materials and geopolymers. The best geopolymer was calcined raw material at 700°C, Davidovits highest ratio 0.82, presenting fresh workability and greater mechanical compressive strength above 10.0MPa for 3 days when compared to the standards for CP II E 32 type cement.
DOI: 10.6084/m9.figshare.12094314.v1
title: Use of sewage sludge in the production of light aggregates: a systematic review of literature

description: ABSTRACT Sewage sludge is the main by-product from wastewater treatment. Its production is growing worldwide. At the same time, environmental agencies have been restricting various methods of disposal of this waste, increasingly demanding the creation of sustainable practices. In this context, construction stands out as a potential partner. Several studies have used sewage sludge in the development of new building materials, including lightweight aggregate (LWA). Thus, this study evaluated, from a systematic review of the literature, the potential application of sewage sludge in the light aggregate manufacturing process. Important data such as: chemical composition; density; granulometry; mechanical resistance; absorption; sintering temperature; concrete application and leaching, international guidelines and / or commercial aggregates were analyzed and compared. The results are encouraging, since in all evaluated aggregates the sewage sludge aggregates met international standards and / or showed similar results to those of commercial aggregates. Therefore, it has been demonstrated that sewage sludge has technical feasibility for LWA's manufacture, confirming the potential of sustainable management of this waste.
DOI: 10.6084/m9.figshare.12094314
title: Use of sewage sludge in the production of light aggregates: a systematic review of literature

description: ABSTRACT Sewage sludge is the main by-product from wastewater treatment. Its production is growing worldwide. At the same time, environmental agencies have been restricting various methods of disposal of this waste, increasingly demanding the creation of sustainable practices. In this context, construction stands out as a potential partner. Several studies have used sewage sludge in the development of new building materials, including lightweight aggregate (LWA). Thus, this study evaluated, from a systematic review of the literature, the potential application of sewage sludge in the light aggregate manufacturing process. Important data such as: chemical composition; density; granulometry; mechanical resistance; absorption; sintering temperature; concrete application and leaching, international guidelines and / or commercial aggregates were analyzed and compared. The results are encouraging, since in all evaluated aggregates the sewage sludge aggregates met international standards and / or showed similar results to those of commercial aggregates. Therefore, it has been demonstrated that sewage sludge has technical feasibility for LWA's manufacture, confirming the potential of sustainable management of this waste.
DOI: 10.6084/m9.figshare.12094332
title: Red mud geopolymerization: the influence of naoh concentration in the synthesis at room temperature

description: ABSTRACT The red mud residue of the Bayer process has proved to be adequate in the geopolymerization reaction. The concentration of the activator influences the mechanical performance of the geopolymers. The aim of this research was to evaluate the mechanical performance of Davidovits (SiO2/Al2O3) geopolymers of 2.09, 1.66 and 2.03 ratio synthesized with different NaOH molar concentrations (5, 10, 15, 30 and 40 Molar) on the activator. The mechanical strength test was performed at 24 hours, 7 and 28 days of curing the geopolymers. The geopolymerization reaction was conducted at room temperature of 28°C. Sodium hydroxide (NaOH) and sodium silicate (Na2 SiO3) 10 Molar were used as the activator. The geopolymer based on metakaolin of 2.09 showed better mechanical resistance, followed by the material with 10% red mud and 90% metakaolin and50% metakaolin and 50% red mud. with 2.03 and 1.66 SiO2/Al2O3 ratios, respectively. In sequence,the materials were characterized by XRF, XRD, laser particle size analysis, scanning electron microscopy (SEM) and EDS of both raw material and geopolymer fragments. Therefore, the geopolymerization of the red mudpresented great potential for the production of geopolymeric materials.
DOI: 10.6084/m9.figshare.12094332.v1
title: Red mud geopolymerization: the influence of naoh concentration in the synthesis at room temperature

description: ABSTRACT The red mud residue of the Bayer process has proved to be adequate in the geopolymerization reaction. The concentration of the activator influences the mechanical performance of the geopolymers. The aim of this research was to evaluate the mechanical performance of Davidovits (SiO2/Al2O3) geopolymers of 2.09, 1.66 and 2.03 ratio synthesized with different NaOH molar concentrations (5, 10, 15, 30 and 40 Molar) on the activator. The mechanical strength test was performed at 24 hours, 7 and 28 days of curing the geopolymers. The geopolymerization reaction was conducted at room temperature of 28°C. Sodium hydroxide (NaOH) and sodium silicate (Na2 SiO3) 10 Molar were used as the activator. The geopolymer based on metakaolin of 2.09 showed better mechanical resistance, followed by the material with 10% red mud and 90% metakaolin and50% metakaolin and 50% red mud. with 2.03 and 1.66 SiO2/Al2O3 ratios, respectively. In sequence,the materials were characterized by XRF, XRD, laser particle size analysis, scanning electron microscopy (SEM) and EDS of both raw material and geopolymer fragments. Therefore, the geopolymerization of the red mudpresented great potential for the production of geopolymeric materials.
DOI: 10.6084/m9.figshare.12094335
title: Archeometric characterization of pre-Hispanic beads and ceramics from Huanchaco by physical techniques and methods

description: ABSTRACT The present study is concerned with the characterization of archaeological materials of beads and ceramics, from the archaeological sites "Iglesia Colonial" and "Pampa La Cruz" of Huanchaco, respectively. The beads of "Iglesia Colonial" were recorded in funerary contexts of the Chimu Inca Period (1450-1532 A.D.) and Early Colonial Period (1532-1650 A.D.). The importance of studying this site lies in understanding the evolution of human occupation between the Inca transition and the arrival of the Spaniards to the north coast of Peru. In the “Pampa La Cruz” site, tombs containing beads and ceramic vessels prepared with the decorative technique of “the negative" were discovered. In this work fragments of the ceramics of this site were investigated, its mineralogical composition was determined qualitatively and quantitatively. This information would help to identify the possible source of clays used for the preparation of the vessels, which, in turn, could help determine if the vessels came from various places, or if the site's inhabitants themselves processed them.
DOI: 10.6084/m9.figshare.12094335.v1
title: Archeometric characterization of pre-Hispanic beads and ceramics from Huanchaco by physical techniques and methods

description: ABSTRACT The present study is concerned with the characterization of archaeological materials of beads and ceramics, from the archaeological sites "Iglesia Colonial" and "Pampa La Cruz" of Huanchaco, respectively. The beads of "Iglesia Colonial" were recorded in funerary contexts of the Chimu Inca Period (1450-1532 A.D.) and Early Colonial Period (1532-1650 A.D.). The importance of studying this site lies in understanding the evolution of human occupation between the Inca transition and the arrival of the Spaniards to the north coast of Peru. In the “Pampa La Cruz” site, tombs containing beads and ceramic vessels prepared with the decorative technique of “the negative" were discovered. In this work fragments of the ceramics of this site were investigated, its mineralogical composition was determined qualitatively and quantitatively. This information would help to identify the possible source of clays used for the preparation of the vessels, which, in turn, could help determine if the vessels came from various places, or if the site's inhabitants themselves processed them.
DOI: 10.5281/zenodo.4639826
title: One-pot synthesis of high-capacity silicon-lithium anodes via on-copper growth of a semi-conducting, porous polymer

description: [This repository contains the source data for the manuscript <strong>"One-pot synthesis of high-capacity silicon-lithium anodes <em>via</em> on-copper growth of a semi-conducting, porous polymer"</strong>] Silicon-based anodes with lithium ions as charge carriers have the highest predicted charge density of 3579 mA h g<sup>-1</sup> (for Li<sub>15</sub>Si<sub>4</sub>) while being comparatively safe. Contemporary electrodes do not achieve these theoretical values largely because production paradigms remained unchanged since their inception and rely on the mixing of weakly coordinated, multiple components. In this paper, we present the one-pot synthesis of high-performance anodes that reach the theoretical capacity of the fully lithiated state of silicon. Here, a semi-conductive triazine-based graphdiyne polymer network is grown around silicon nanoparticles directly on the current collector, a copper sheet. The current collector (Cu) acts as the catalyst for the formation of a semi-conductive triazine-based graphdiyne polymer network that grows around the inorganic, active material (Si). In comparison to established electrode assemblies, this process (i) omits any steps related to curing, drying, and annealing, (ii) does away with binders and conductivity-enhancing additives that decrease volumetric and gravimetric capacity, and (iii) cancels out the detrimental effects on performance, chemical and physical stability of conventional, three-component anodes (Si, binder, carbon black). This is because, the porous, semi-conducting organic framework (i) adheres to the current collector on which it grows <em>via</em> cooperative van der Waals interactions, (ii) acts effectively as conductor for electrical charges and binder of silicon nanoparticles <em>via</em> conjugated, covalent bonds, and (iii) enables selective transport of mass and charge-carriers (electrolyte and Li-ions) through pores of defined size. As a result, the anode shows extraordinarily high capacity at the theoretical limit of fully lithiated silicon, excellent performances in terms of cycling (exceeding 70% capacity retention after 100 cycles), and high mechanical and thermal stability. These high-performance anodes pave the way for use in flexible, wearable electronics and in environmentally demanding applications.
DOI: 10.6084/m9.figshare.14321587
title: Effect of zinc substitution by nickel on solids with hydrotalcite type structure

description: ABSTRACT Hydrotalcites can be used for different applications due to their chemical properties and to give rise to solids with high specific surface area, good thermal stability, high dispersion and basic character. These characteristics have led to the fact that these materials have received much attention and application in areas such as the removal of contaminants and the synthesis of catalysts. This study evaluated the effect of zinc substitution by nickel on zinc-aluminum hydrotalcites, which have shown activity for the catalytic depolymerization of poly(ethylene terephthalate). The hydrotalcite type structure was observed in all materials, noting that the increase of zinc leads to higher values of a parameter of the orthorhombic cells of the hydrotalcites. The decrease of the c parameter led to a greater interaction CO32-‧ ‧ ‧ OH in the interlaminar space. Solids with higher zinc content collapsed at lower temperatures, contrary to that induced by nickel. The calcined solids contain the ZnO, NiO y g-Al2O3 phases, whose presence depends on the metals present. The results suggest the presence of large particles with high crystallinity of the ZnO phase, whereas the broad peaks of NiO suggest the existence of small particles of this phase, whose crystallinity is affected by the presence of Zn2+ and Al3+ in the cubic lattice of NiO. Materials containing two metals presented isotherms characteristic of predominantly macroporous solids. In relation to the materials with three metals, the structures are mesoporous and with high specific surface area, observing that the solid Zn0,44Ni0,22Al0,33 contains slit-shaped pores, while the solids Zn0,33Ni0,33Al0,33 and Ni0,44Zn0,22Al0,33 presented typical isotherms of materials with narrow pores in the form of capillaries.