Beeswax-poly(vinyl alcohol) composite films for bread packaging.

The study aimed to improve the barrier characteristics of polyvinyl alcohol (PVA) film by adding beeswax (BW) and glycerin and by heat treatment in order to become a potential suitable material for bread packaging. XRD, FTIR and XPS showed new cross-links between PVA and beeswax demonstrating the composite nature of the film. TGA-DTA showed that glycerin reduced the dehydration and that the beeswax improved theirs thermal stability.

The effect of nanoceria on the alginate-gum arabic crosslinking mechanism and in vitro behavior as a wound dressing.

Medical practice has proven that chronic wounds can be treated successfully if the dressing is chosen according to the healing phase of the wound. Correct intervention from the hemostasis and inflammatory phase can prevent oxidative stress and ensure optimal conditions for healing. It is important to design a new wound dressing that does not cause additional injury, has an antioxidant effect, removes dead cells, and promotes wound healing.

TiO-Alginate-Chitosan-Based Composites for Skin Tissue Engineering Applications.

The UV-B component of sunlight damages the DNA in skin cells, which can lead to skin cancer and premature aging. Therefore, it is necessary to use creams that also contain UV-active substances. Many sunscreens contain titanium dioxide due to its capacity to absorb UV-B wavelengths.

Ultrasensitive Electroanalytical Detection of Pb and HO Using Bi and Fe-Based Nanoparticles Embedded into Porous Carbon Xerogel-The Influence of Nanocomposite Pyrolysis Temperatures.

Multifunctional materials based on carbon xerogel (CX) with embedded bismuth (Bi) and iron (Fe) nanoparticles are tested for ultrasensitive amperometric detection of lead cation (Pb) and hydrogen peroxide (HO). The prepared CXBiFe-T nanocomposites were annealed at different pyrolysis temperatures (T, between 600 and 1050 °C) and characterized by X-ray diffraction (XRD), Raman spectroscopy, N adsorption, dynamic light scattering (DLS), and electron microscopies (SEM/EDX and TEM). Electrochemical impedance spectroscopy (EIS) and square wave anodic stripping voltammetry (SWV) performed at glassy carbon (GC) electrodes modified with chitosan (Chi)-CXBiFe-T evidenced that GC/Chi-CXBiFe-1050 electrodes exhibit excellent analytical behavior for Pb and HO amperometric detection: high sensitivity for Pb (9.

Photoinhibitive Properties of α-MoO on Its Composites with TiO, ZnO, BiOI, AgBr, and CuO.

Orthorhombic molybdenum trioxide (α-MoO) is well known as a photocatalyst, adsorbent, and inhibitor during methyl orange photocatalytic degradation via TiO. Therefore, besides the latter, other active photocatalysts, such as AgBr, ZnO, BiOI, and CuO, were assessed via the degradation of methyl orange and phenol in the presence of α-MoO using UV-A- and visible-light irradiation. Even though α-MoO could be used as a visible-light-driven photocatalyst, our results demonstrated that its presence in the reaction medium strongly inhibits the photocatalytic activity of TiO, BiOI, CuO, and ZnO, while only the activity AgBr is not affected.

Anionic Polysaccharide Cryogels: Interaction and In Vitro Behavior of Alginate-Gum Arabic Composites.

In the present study, polysaccharide-based cryogels demonstrate their potential to mimic a synthetic extracellular matrix. Alginate-based cryogel composites with different gum arabic ratios were synthesized by an external ionic cross-linking protocol, and the interaction between the anionic polysaccharides was investigated. The structural features provided by FT-IR, Raman, and MAS NMR spectra analysis indicated that a chelation mechanism is the main process linking the two biopolymers.

Rapid Synthesis Method of AgPO as Reusable Photocatalytically Active Semiconductor.

The widespread use of AgPO is not surprising when considering its higher photostability compared to other silver-based materials. The present work deals with the facile precipitation method of silver phosphate. The effects of four different phosphate sources (HPO, NaHPO, NaHPO, NaPO·12 HO) and two different initial concentrations (0.

Insights into the Stability of Graphene Oxide Aqueous Dispersions.

Understanding graphene oxide's stability (or lack thereof) in liquid solvents is critical for fine-tuning the material's characteristics and its potential involvement in future applications. In this work, through the use of structural and surface investigations, the alteration of the structural and edge-surface properties of 2D graphene oxide nanosheets was monitored over a period of eight weeks by involving DLS, zeta potential, XRD, XPS, Raman and FT-IR spectroscopy techniques. The samples were synthesized as an aqueous suspension by an original modified Marcano-Tour method centred on the sono-chemical exfoliation of graphite.

Shape tailoring of AgBr microstructures: effect of the cations of different bromide sources and applied surfactants.

Investigations regarding AgBr-based photocatalysts came to the center of attention due to their high photosensitivity. The present research focuses on the systematic investigation regarding the effect of different alkali metal cation radii and surfactants/capping agents applied during the synthesis of silver-halides. Their morpho-structural and optical properties were determined X-ray diffractometry, diffuse reflectance spectroscopy, scanning electron microscopy, infrared spectroscopy, and contact angle measurements.

Bioactive Properties of Composites Based on Silicate Glasses and Different Silver and Gold Structures.

Using an ideal biomaterial to treat injured bones can accelerate the healing process and simultaneously exhibit antibacterial properties; thus protecting the patient from bacterial infections. Therefore, the aim of this work was to synthesize composites containing silicate-based bioactive glasses and different types of noble metal structures (i.e.

Thermal Evolution of C-Fe-Bi Nanocomposite System: From Nanoparticle Formation to Heterogeneous Graphitization Stage.

Carbon xerogel nanocomposites with integrated Bi and Fe particles (C–Bi–Fe) represent an interesting model of carbon nanostructures decorated with multifunctional nanoparticles (NPs) with applicability for electrochemical sensors and catalysts. The present study addresses the fundamental aspects of the catalyzed growth of nano-graphites in C–Bi–Fe systems, relevant in charge transport and thermo-chemical processes. The thermal evolution of a C–Bi–Fe xerogel is investigated using different pyrolysis treatments.

Optimization Method of the Solvothermal Parameters Using Box-Behnken Experimental Design-The Case Study of ZnO Structural and Catalytic Tailoring.

ZnO photocatalysts were synthesized via solvothermal method and a reduced experimental design (Box-Behnken) was applied to investigate the influence of four parameters (temperature, duration, composition of the reaction mixture) upon the photocatalytic activity and the crystal structure of ZnO. The four parameters were correlated with photocatalytic degradation of methyl orange and the ratio of two crystallographic facets ((002) and (100)) using a quadratic model. The quadratic model shows good fit for both responses.

Bioactive glass-biopolymers‑gold nanoparticle based composites for tissue engineering applications.

Biomaterials based on bioactive glass with gold nanoparticle composites have many applications in tissue engineering due to their tissue regeneration and angiogenesis capacities. The objectives of the study were to develop new composites using bioactive glass with gold nanospheres (BGAuSP) and gold nanocages (BGAuIND), individually introduced in alginate-pullulan (Alg-Pll) polymer, to evaluate their biocompatibility potential, and to compare the obtained results with those achieved when β-tricalcium phosphate-hydroxyapatite (βTCP/HA) replaced the BG. The novel composites underwent structural and morphological characterization followed by in vitro viability testing on fibroblast and osteoblast cell lines.

Poly(Vinyl Chloride) Spheres Coated with Graphene Oxide Sheets: From Synthesis to Optical Properties and Their Applications as Flame-Retardant Agents.

A new method to obtain poly(vinyl chloride) (PVC) spheres, which consists of an interaction between commercial PVC grains and hexyl ethyl cellulose and lauroyl peroxide at a temperature of 60 °C, is reported. The addition of the graphene oxide (GO) sheets dispersed in dimethylformamide to the reaction mixture leads to the generation of composites made of PVC spheres coated with GO sheets. Scanning electron microscopy studies have demonstrated that this method allows for the transformation of PVC grains with sizes between 75 and 227 μm into spheres with sizes varying from 0.

The Effect of the Reducing Sugars in the Synthesis of Visible-Light-Active Copper(I) Oxide Photocatalyst.

In the present work, shape tailored CuO microparticles were synthesized by changing the nature of the reducing agent and studied subsequently. d-(+)-glucose, d-(+)-fructose, d-(+)xylose, d-(+)-galactose, and d-(+)-arabinose were chosen as reducing agents due to their different reducing abilities. The morpho-structural characteristics were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), and diffuse reflectance spectroscopy (DRS), while their photocatalytic activity was evaluated by methyl orange degradation under visible light (120 min).

The Impact of Composites with Silicate-Based Glasses and Gold Nanoparticles on Skin Wound Regeneration.

The silver content of the skin regeneration ointments can influence its regeneration process but in the meantime, it can take the benefit of the antibacterial properties of silver by avoiding the bacterial infection of an open wound. In the current study, the skin healing and regeneration capacity of bioactive glass with spherical gold nanocages (BGAuIND) in the Vaseline ointments were evaluated in vivo comparing the bioactive glass (BG)-Vaseline and bioactive glass with spherical gold (BGAuSP)-Vaseline ointments. Spherical gold nanocages are stabilized with silver and as a consequence the BGAuIND exhibits great antibacterial activity.

3-Aminopropyl-Triethoxysilane Functionalized Graphene Oxide for Silane-Based Consolidation Treatments to Increase Mortar Performances.

The influence of chemically converted GO (graphene oxide) functionalized with APTES (3-aminopropyl-triethoxysilane) and unfunctionalized GO, dispersed in ethanolic solution of TEOS (tetraethyl orthosilicate), on the performances of the mortar samples, such as capillary water absorption and compressive strength was evaluated. The effect of the GO based nanomaterials (GO and GO functionalized with APTES) on the mortar microstructure was investigated by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Raman spectroscopy and scanning electron microscopy (SEM). The multifunctionality of the mortar brushed with GO based nanomaterials consolidation suspension was proved by the results (i) of the mechanical tests which show an improvement of the compressive strength and (ii) the capillary water absorption results which indicate the decreasing of the water penetration speed.

Preparation and Characterization of Carbon Xerogel Based Composites for Electrochemical Sensing and Photocatalytic Degradation.

In order to obtain a multifunctional nanocomposite material-for electrochemical sensors and photocatalytic applications, structures based on Bi, Fe and TiO₂ were grown inside carbon xerogel supports (BiFeCX and BiFeCX-TiO₂). First, a wet polymer containing Bi and Fe salts was obtained by following a modified resorcinol-formaldehyde based sol-gel route, followed by drying in ambient conditions, and pyrolysis under inert atmosphere. Then, through TiCl₄ hydrolysis, TiO₂ nanoparticles were deposited on the BiFeCX xerogel leading to BiFeCX-TiO₂.

Mixture of Graphene Oxide/Phosphoric Acid/Melamine as Coating for Improved Fire Protective Performance and Enhancement of Surface Electrical Properties on Wood Chipboard.

Looking for multifunctional materials, an assessment of the performances both as fire retardant and generator of electrically conductive surfaces for a three component mixture of graphene oxide, phosphoric acid and melamine applied on wood chipboard was performed. A simple approach was used to investigate the intumescent char formation and quantify the loss mass during vertical burning tests, in which the prepared samples were exposed for a certain time interval to a flame generated by an ethanol lamp in ambient conditions. Moreover, mass loss evolution and structural changes that occur during the burning process were more comprehensive investigated by differential thermal and thermogravimetric (DTA/TGA) techniques.

Gypsum Composite Boards Incorporating Phase Change Materials: A Review.

The purpose of this review is to provide an overview of the available gypsum based composite including various phase change materials employed to increase the thermal energy storage capacity of building materials. A wide range of materials such as n-alkane, saturated fatty acid, fatty acid esters etc are used as phase change materials. Adding carbonaceous material (carbon nanofibers, activated nanocarbon, graphite nanosheets etc.

Carbon Xerogel Nanostructures with Integrated Bi and Fe Components for Hydrogen Peroxide and Heavy Metal Detection.

Multifunctional Bi- and Fe-modified carbon xerogel composites (CXBiFe), with different Fe concentrations, were obtained by a resorcinol-formaldehyde sol-gel method, followed by drying in ambient conditions and pyrolysis treatment. The morphological and structural characterization performed by X-ray diffraction (XRD), Raman spectroscopy, N adsorption/desorption porosimetry, scanning electron microscopy (SEM) and scanning/transmission electron microscopy (STEM) analyses, indicates the formation of carbon-based nanocomposites with integrated Bi and Fe oxide nanoparticles. At higher Fe concentrations, Bi-Fe-O interactions lead to the formation of hybrid nanostructures and off-stoichiometric BiFeO mullite-like structures together with an excess of iron oxide nanoparticles.

New Insights into The Photoactivity of Shape-Tailored BiVO Semiconductors via Photocatalytic Degradation Reactions and Classical Reduction Processes.

In the present study, additive-free, pH-driven, hydrothermal crystallization was used to obtain shape-tailored monoclinic BiVO photocatalysts. The as-prepared BiVO products were systematically characterized, uncovering their crystallographic, morphologic and optical properties, while their applicability was verified in the visible light-driven photodegradation of oxalic acid and rhodamine B. Monoclinic clinobisvanite was obtained in most cases, with their band gap values located between 2.