A5085351261- Magnetic Properties and Synthesis of Ferrites
- Iron oxide chemistry and applications
- Magnetic properties of thin films
- Bone Tissue Engineering Materials
- Dental Implant Techniques and Outcomes
- Ferroelectric and Piezoelectric Materials
- Multiferroics and related materials
- Mineralogy and Gemology Studies
- Crystal Structures and Properties
- Dyeing and Modifying Textile Fibers
- Dental materials and restorations
- Carbon Dioxide Capture Technologies
- Copper-based nanomaterials and applications
- biodegradable polymer synthesis and properties
- Bee Products Chemical Analysis
- Minerals Flotation and Separation Techniques
- Characterization and Applications of Magnetic Nanoparticles
- Membrane Separation and Gas Transport
- Antioxidant Activity and Oxidative Stress
- Geochemistry and Geologic Mapping
- Ammonia Synthesis and Nitrogen Reduction
- CO2 Sequestration and Geologic Interactions
- Dielectric properties of ceramics
- Gas Sensing Nanomaterials and Sensors
- Nanoparticle-Based Drug Delivery
University of Copenhagen
2020-2025
Universidade Federal de Campina Grande
2005-2023
Universidade Federal de Goiás
2017
Universidade Federal de Sergipe
2011-2014
The main source of commercial chitosan is the extensive deacetylation its parent polymer chitin. It present in green algae, cell walls or fungi and exoskeleton crustaceans. A novel procedure for preparing from shrimp shells was developed. involves two 10-minutes bleaching steps with ethanol after usual demineralization deproteinization processes. Before deacetylation, chitin immersed 12.5 M NaOH, cooled down kept frozen 24 h. obtained characterized using scanning electron microscopy (SEM),...
The ubiquity of nonbiodegradable polyethylene terephthalate (PET) materials has led to significant waste management challenges. Although PET plastics can be recycled, blended materials, such as PET/cotton fabrics, complicate the recycling process due labile glycosidic bonds in cotton. In this study, we present a practical and scalable approach for interwoven fabrics via catalytic glycolysis with ammonium bicarbonate (NH4HCO3), which decomposed ammonia, carbon dioxide, water. This...
Ni(1-x)FexO nanoparticles have been obtained by the co-precipitation chemical route. X-ray diffraction analyses using Rietveld refinement shown a slight decrease in microstrain and mean particle size as function of Fe content. The zero-field-cooling (ZFC) field-cooling (FC) magnetization curves show superparamagnetic behavior at high temperatures low temperature peak (at T = 11 K), which is enhanced with increasing concentration. Unusual coercive field region an exchange bias were also...
Polyethyleneimine (PEI) is a widely used polymer in catalysis, gas separation, water treatment, drug delivery, textile, and paper production. We propose new method of transforming hydrophobic hygroscopic PEIs into crystalline materials via simple alkylation. The structure the alkylated was characterized using powder X-ray diffraction, small-angle scattering, thermogravimetric analysis, inelastic neutron scattering. Consequently, amine-rich demonstrates CO2 responsiveness for CO2-mediated...
Polyethyleneimine (PEI) is a widely used polymer in catalysis, gas separation, water treatment, drug delivery, textiles, and paper production. Herein, we investigate the crystalline structure of hydrophobic PEIs, prepared via simple alkylation as previously reported, using powder X‐ray diffraction, small‐angle scattering, thermogravimetric analysis, inelastic neutron scattering. This work presents comprehensive analysis structural changes alkylated PEIs during CO2‐mediated desalination...
Gastrin-releasing peptide (GRP) has been proposed as a major growth factor in brain tumors, and GRP receptor (GRPR) antagonists show antiproliferative effects experimental gliomas. However, the underlying molecular events downstream of GRPR activation remain poorly understood. In present study, we examined role regulating proliferation glioma cells vitro its possible interaction with phosphatidylinositol 3-kinase (PI3K) signaling pathway. Expression mRNA protein C6, U-87MG, U-373MG was...
We present a systematic study of the coercive field CoFe2O4–SiO2 nanocomposites. The samples were prepared via sol-gel method by using Tetraethyl Orthosilicate as starting reagent. Results X-ray diffraction, transmission electron microscopy, and fluorescence confirm dispersion magnetic nanoparticles inside silica matrix. In addition, shift in maximum Zero-Field-Cooled curves observed varying weight ratio CoFe2O4 to precursor is consistent with increasing average interparticle distances....
Developing new technologies for carbon sequestration and long-term storage is important. Clay minerals are interesting in this context as they low-cost, naturally abundant, can adsorb considerable amounts of CO2, present sites anthropogenic carbon. Here, to better understand the intercalation mechanisms CO2 dehydrated hydrated synthetic Na-fluorohectorite clay, we have combined powder X-ray diffraction, inelastic quasi-elastic neutron scattering, density functional theory calculations. For...
We have studied the influence of chelating agents (glycerin and sucrose) on structural magnetic properties cobalt ferrite (CoFe2O4) nanoparticles synthesized via co-precipitation method. The Rietveld refinements from X-ray diffraction patterns confirm that all samples are single phase identified in a cubic crystalline system belonging to space group Fd-3m. Besides, we verified addition produces decreasing particles average size 14(2) 5(1) nm. Magnetization measurements as function...
Antiferromagnetic Co3O4 nanoparticles were synthesized by the coprecipitation method. With addition of sucrose as chelating agent (sucrose) size particles was reduced from 54 nm to 19 nm. The exhibit a cubic spinel structure identified for X-ray diffraction (XRD) and confirmed Rietveld refinement. Scanning Electron Microscopy (SEM) images spherical-like morphology confirm decrease particle observed XRD. magnetic measurements function temperature using superconducting quantum interference...
In this work we have studied the role of addition chelating agents on structural and magnetic properties α-Fe2O3 nanoparticles obtained by co-precipitation method. The precursors were prepared for different concentrations agents: sucrose glycerine. To obtain nanoparticles, these heated in temperature range between 200 400 °C. samples been characterized via x-ray diffraction (XRD), scanning electron microscopy (SEM), magnetization measurements. XRD data confirm that crystalline phase is...
Human hair is a biopolymer constituted mainly of keratin intermediate filaments, lipids, pigments and water. Cosmetic treatments usually interact with the at molecular level, inducing changes in its components modifying physicochemical mechanical properties fibers. Here, effect acid straightening on morphology ultrastructure Caucasian was investigated by group complementary experimental methods: wide-, small- ultra-small-angle X-ray scattering; high-resolution 3D microscopy; quasi-elastic...
Sustainable hydrogen production requires large amounts of treated freshwater and precious metals. Direct electrolysis seawater without additional electrolytes can be a practical approach to address these limitations, however, it usually suffers from kinetically favored chlorine evolution reaction (CER), which is detrimental an system. We report that organocatalytic amphiphilic diamines play crucial role in preventing the generation gas. The feasibility direct was demonstrated with...
Addressing atmospheric CO 2 levels during the transition to carbon neutrality requires efficient capture methods. Aqueous amine scrubbing dominates large‐scale flue gas but is hampered by energy‐intensive regeneration step, sorbent loss, and consequent environmental concerns with volatile amines. Herein, hydrophobic non‐volatile alkylated monoethanolamine (MEA) introduced as a water‐lean absorbent in brine. The effects of alkylation MEA, salinity, aggregation absorbents on improved process...
Abstract The hydroxyapatite (HAp) is a ceramic biomaterial with wide application in the bone regeneration. It can be obtained by different routes and precursors. In this study, synthesis of HAp was carried out precipitation subsequent thermal treatment using calcium precursors: hydroxide from synthetic origin oxide eggshell. materials were characterized X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy. By SEM, variations crystal size...
The fascinating structural flexibility of porous polymers is highly attractive because it can result in optimized materials with specific host–guest interactions. Nevertheless, the fundamental mechanisms responsible for controlling weak interactions these hydrogen bond-rich networks—essential developing smart task-specific used recognition, capture, and sequestration processes—remain unexplored. Herein, by systematically comparing performance changes between poly(amic acid) (PAA)- polycyclic...
O skarn de Umbuzeiro Doce está localizado na localidade São Gonçalo, município Santa Luzia, Estado da Paraíba, Província Scheelitífera Borborema, região do Seridó. Trata-se uma pequena lente scheelitífera orientada segundo a direção NE-SW, com mergulho médio 60° para NW e encaixada parte intermediária camada mármore branco, contendo em ordem decrescente percentual modal calcita, granada, vesuvianita, epídoto, diopsídio, actinolita, scheelita, flogopita magnetita. A vesuvianita violeta...