Aggregation-induced emission (AIE) molecules are nonemissive in dilute solution but emit intensely upon aggregation in complete contrast to aggregation-caused quenching (ACQ) molecules. The emission of ACQ molecules, such as fluorescein, that have been encapsulated into the hydrophilic nanopores in a cyclodextrin-based metal-organic framework (CD-MOF) was reported to be enhanced due to the disappearance of concentration quenching and the restriction of thermal motion. However, the contribution of the restriction of thermal motion in CD-MOF could not be elucidated. In this study, an AIE-active L-cysteine/Au(I) (L-Cys/Au(I)) complex was synthesized and introduced into the nanopores of CD-MOF via a co-crystallization method. We determined the amount and chemical composition of the L-Cys/Au(I) complex in CD-MOF. The fluorescence intensity of the L-Cys/Au(I)@CD-MOF composite was investigated. The L-Cys/Au(I) complex that was synthesized from Au(III) chloride and L-cysteine was found to be a... [more]

Chiral organic and organometallic luminophores that possess circularly polarized luminescence (CPL) properties in the near-ultraviolet to near-infrared region have several useful applications. However, the CPL properties are subject to inherent factors of the compounds; to date, studies on the CPL properties influenced by amino acids and peptides are scarce. Consequently, we developed peptide-pyrene organic luminophores exhibiting various CPL properties. It is conceivable that the peptide-pyrene organic luminophores can be obtained as aggregates when dissolved in a solution. It is also possible that the formation of aggregates makes it difficult to accurately examine the CPL of the peptide in the solution. This study showed that the introduction of sterically hindered 2-aminoisobutyric acid (Aib) units into the peptide backbone inhibits aggregate formation. The resulting luminophores exhibit CPL properties owing to the presence of pyrene units. The results of this study can form a basi... [more]

The proposal of this work was the preparation and characterization of activated carbons obtained from water treatment plant sludge (WTS) to apply as adsorbents in the removal of organic dye contaminants from wastewater. The activated carbons were produced with a combination of chemical activation and pyrolysis processes. The textural characteristics of both adsorbents presented a satisfactory superficial area and mesoporous structure. The presence of phenolic and carboxylic groups in the surface indicated a better adsorption of cationic adsorbates. When applied as adsorbents in the removal of methylene blue (MB) from wastewater, the maximum removal values obtained were up to 96%. The adsorption results showed that the adsorption was faster in the beginning and reached maximum around 30 min. The Elovich kinetic model and the Sips isotherm model presented the best fit to experimental data, which was checked by analysis of variance (ANOVA). The production of activated carbons from WTS is... [more]

The present work investigated the potential of using zeolite (clinoptilolite), montmorillonite (Swy2), and Conocarpus biochar as adsorbents to remove 226Ra from aqueous solution. The effect of the initial 226Ra concentrations on sorbents’ equilibrium activity concentrations and sorbents’ radium removal efficiency were investigated. The results showed that zeolite has a higher removal efficiency for 226Ra in comparison with the efficiencies of montmorillonite and biochar. In addition to the linear isotherm model, the Freundlich model, followed by Temkin’s model, provided a better description of the adsorption process than the Langmuir model. Kinetic studies indicated that a pseudo-second-order kinetic model could be the best fit for the adsorption of 226Ra onto the three investigated sorbents, which suggests that the mechanism of adsorption of 226Ra by sorbents was chemisorption. The intraparticle diffusion model indicated that adsorption of 226Ra onto the sorbents involves a multistep... [more]

The addition of nanoparticles to liquid media can improve thermomechanical properties of dispersants. This ability gives rise to the development of multiple applications of nanofluids (NF) in branches so different as electronic and photonic devices or cosmetic industry. Logically, these applications require a good control of heat transfer and flow properties. Moreover, if we consider the necessity to optimize industrial processes in which NF take part, it is necessary to obtain possible relationships between both physical mechanisms. Specifically, in this work, a study about thermal conductivity and rheological behavior of fumed silica suspensions in polypropylene glycol (PPG400) and polyethylene glycol (PEG200) was performed. The study of these two suspensions is interesting because the flow behaviors are very dissimilar (while the fumed silica in PEG200 suspension is viscoplastic, the fumed silica in PPG400 suspension shows shear-thickening behavior between two shear-thinning regions... [more]

The effects of a hydrogen bond acceptor and hydrogen bond donor on carbon dioxide absorption via natural deep eutectic solvents were studied in this work. Naturally occurring non-toxic deep eutectic solvent constituents were considered; choline chloride, b-alanine, and betaine were selected as hydrogen bond acceptors; lactic acid, malic acid, and fructose were selected as hydrogen bond donors. Experimental gas absorption data were collected via experimental methods that uses gravimetric principles. Carbon dioxide capture data for an isolated hydrogen bond donor and hydrogen bond acceptor, as well as natural deep eutectic solvents, were collected. In addition to experimental data, a theoretical study using Density Functional Theory was carried out to analyze the properties of these fluids from the nanoscopic viewpoint and their relationship with the macroscopic behavior of the system, and its ability for carbon dioxide absorption. The combined experimental and theoretical reported appro... [more]

In response to increasingly stringent requirements for the sustainability and environmental friendliness of the rubber industry, the application and development of bio-based elastomers have received extensive attention. In this work, we prepared a new type of bio-based elastomer poly(dibutyl itaconate-butadiene) copolymer (PDBIB) nanocomposite using carbon black and non-petroleum-based silica with a coupling agent. Using dynamic thermodynamic analysis (DMTA) and scanning electron microscope (SEM), we studied the effects of feed ratio on dynamic mechanical properties, micro morphology, and filler dispersion of PDBIB composites. Among them, silica-reinforced PDBIB60 (weight ratio of dibutyl itaconate to butadiene 40/60) and carbon black-reinforced PDBIB70 (weight ratio of dibutyl itaconate to butadiene 30/70) both showed excellent performance, such as tensile strength higher than 18 MPa and an elongation break higher than 400%. Compared with the widely used ESBR, the results showed that... [more]

Fine particles are widely used in many industrial fields, and there are many techniques applied for these particles, like electroplating, and chemical and physical vapor deposition. However, in the food and pharmaceutical industries, most coating processes conducted with fluidized bed use core particles with a diameter larger than 200 μm, otherwise agglomerates are formed. This study contributes to the development of a new coating process for fine particles with diameters of around 50 μm. The innovation lies in the combined use of a Wurster fluidized bed and a novel aerosol atomizer. The feasibility of the operation is based on the application of the aerosol atomizer, which generates droplets smaller than 1 μm in diameter. A series of experiments with different coating solutions and glass beads in a 150 mm fluidized bed fed with droplet aerosol supplied from the cone chamber bottom is presented. The quality of the coating product is analyzed by scanning electron microscopy and CAMSIZER... [more]

The contamination of soil and water bodies with mercury from anthropogenic sources such as mining and industry activities causes negative effect for living organisms due to the process of bioaccumulation and biomagnification through the food chain. Therefore, the need for remediation of contaminated areas is extremely necessary and very desirable when it is cost-effective by using low-cost sorbents. This paper compares the sorption abilities of natural and iron-modified zeolite towards Hg(II) ions from aqueous solutions. The influence of pH, solid/liquid ratio (S/L), contact time, and initial concentration on the sorption efficiency onto both zeolites was investigated. At the optimal pH = 2 and S/L = 10, the maximum amount of sorbed Hg(II) is 0.28 mmol/g on the natural zeolite and 0.54 mmol/g on the iron-modified zeolite. It was found that rate-controlling step in mass transfer is intraparticle diffusion accompanied by film diffusion. Ion exchange as a main mechanism, accompanied with... [more]

The current study was designed to demonstrate the efficiency of selected zeolites in the immobilization of heavy metals and volatile organic compounds from water in the industrial area of Tito Scalo (Basilicata Region in Southern Italy). The efficiency of zeolite materials has been evaluated by analyzing real water samples, by a multi-technique approach. Gas chromatography (GC) and inductively coupled plasma optical emission spectrometry (ICP-OES) were selected for the detection of volatile organic compounds (VOCs) and heavy metals respectively, and then by thermal analysis (TG, DTA) and X-ray powder diffraction (XRD) to verify the presence of contaminants in the structural channels of the adsorbents. ZSM-5 zeolite (MFI topology) was suitable for volatile organic compounds, showing removal efficiencies 87%. 13X (FAU topology) was more selective for in situ abatements of heavy metals, with efficiencies up to 100%. After VOCs and heavy metals removal, structure refinements of loaded zeol... [more]

Asphaltenes, as the heaviest and most polar fraction of petroleum, have been characterized by various analytical techniques. A variety of fractionation methods have been carried out to separate asphaltenes into multiple subfractions for further investigation, and some of them have important reference significance. The goal of the current review article is to offer insight into the multitudinous analytical techniques and fractionation methods of asphaltene analysis, following an introduction with regard to the morphologies of metals and heteroatoms in asphaltenes, as well their functions on asphaltene aggregation. Learned lessons and suggestions on possible future work conclude the present review article.

This manuscript describes a novel in situ interfacial dynamic inverse emulsion polymerization process under sonication of aniline in the presence of carbon nanotubes (CNT) and graphene nanoparticles in ethanol. This polymerization method is simple and very rapid (up to 10 min) compared to other techniques reported in the literature. During polymerization, the nanoparticles are coated with polyaniline (PANI), forming a core-shell structure, as confirmed by high-resolution scanning electron microscopy (HRSEM) and Fourier-Transform Infrared (FTIR) measurements. The membrane pore sizes range between 100−200 nm, with an average value of ~119 ± 28.3 nm. The film resistivity decreased when treated with alcohol, and this behavior was used for selection of the most efficient alcohol as a solvent for this polymerization technique. The membrane permeability of the PANI grafted CNT was lower than the CNT reference, thus demonstrating better membranal properties. As measured by water permeability,... [more]

In this paper, ZnCo2O4 nanowire arrays with a uniform carbon coating were introduced when polyvinyl alcohol (PVA) served as the carbon source. The coating process was completed by a facile bath method in PVA aqueous solution and subsequent pyrolyzation. The PVA-derived carbon-coated ZnCo2O4 nanowire array composites can be used directly as the binder-free and self-supported anode materials for lithium-ion batteries. In the carbon-coated ZnCo2O4 composites, the carbon layer carbonized from PVA can accelerate the electron transfer and accommodate the volume swing during the cycling process. The lithium storage properties of the carbon-coated ZnCo2O4 composites are investigated. It is believed that the novel carbon-coating method is universal and can be applied to other nanoarray materials.

Foam materials have been widely used in various industrial applications, where higher and higher heat and mass transfer performances are pursued. However, the mechanism of many factors on the heat transfer performances is still unclear. The main purpose of this article is to investigate how the porous properties, porosity, cell size and the sample thickness affect the volumetric convective heat transfer. In this study, the single-blow method is used to determine the volumetric heat transfer coefficient of ceramics foam in the temperature range from 283 K to 323 K. In particular, sensitivity analysis of the foam porosity, cell size, velocity and the sample thickness on the volumetric heat transfer coefficient within the ceramics foam were all conducted. The results indicate that the sample thickness has a significant effect on the volumetric heat transfer coefficient which decreases with the sample thickness. In addition, the local thermal equilibrium phenomenon is verified and its infl... [more]

The design and synthesis of new multifunctional organic porous polymers has attracted significant attention over the years due to their favorable properties, which make them suitable for carbon dioxide storage. In this study, 2-, 3-, and 4-hydroxybenzaldehyde reacted with phenyltrichlorosilane in the presence of a base, affording the corresponding organosilicons 1−3, which further reacted with benzidine in the presence of glacial acetic acid, yielding the organic polymers 4−6. The synthesized polymers exhibited microporous structures with a surface area of 8.174−18.012 m2 g−1, while their pore volume and total average pore diameter ranged from 0.015−0.035 cm3 g−1 and 1.947−1.952 nm, respectively. In addition, among the synthesized organic polymers, the one with the meta-arrangement structure 5 showed the highest carbon dioxide adsorption capacity at 323 K and 40 bar due to its relatively high surface area and pore volume.

Mineral base oils are used to produce commercial lubricants and are obtained from refining vacuum residue. Lubricants are used to reduce friction in industry devices, so their viscosity is a key characteristic that needs to be optimized throughout the process. The purpose of this study is to show how global chemical characterization of samples from the base oil production chain can facilitate a better understanding of the molecular impacts of processing and their effect on macroscopic properties like viscosity. Eight different samples were characterized by different analytical techniques, including liquid chromatography and mass spectrometry techniques, to understand their chemical evolution through the different process units at the molecular level. Furthermore, a statistical treatment allowed for the identification of parameters that influence viscosity, mainly sulfur and polyaromatics content. This study demonstrates the importance and effectiveness of cross-checking results from di... [more]

Xylindein, a stable quinonic blue-green fungal pigment, has shown potential for use not only as a colorant but also as an (opto)electronic material. As no method presently exists to synthesize the pigment, organic production by slow-growing fungi from the genus Chlorociboria is the only method to obtain it. This has resulted in limited quantities of impure xylindein, hampering research. In order to improve quantity and quality of pigment for optoelectronic applications, speed of xylindein production by Chlorociboria aeruginosa and its relative purity were compared across liquid and solid-state fermentation conditions on selected nutrient sources. Liquid 2% malt shaking cultures produced the same amount of pigment in 5 weeks that previous testing produced in 2 months. Xylindein generation speed, purity, and conductive properties of produced pigment for (opto)electronics was then compared between two Chlorociboria species native to North America, Chlorociboria aeruginosa and Chlorocibori... [more]

For the last twenty years, polymer hybrid nanocomposites have enjoyed unflagging interest from numerous scientific groups and R&D departments, as they provide notable enhancement of properties, even at low nanofillers’ content. Their performance results from many factors, the most important of which is the uniform distribution in the entire volume of the matrix, that still is very challenging, but is the right choice of two types of nanoparticles that can lead to an increase of dispersion stability and even more uniform distribution of fillers. The incorporation of two types of nanofillers, especially when they differ in aspect ratio or chemical nature, allows to additively reduce the price of the final composite by replacing the more expensive filler with the cheaper one, or even synergistically improving the properties, e.g., mechanical, thermal, and barrier, etc., that can extend their usage in the industry. Despite numerous review papers on nanocomposites, there is no review on how... [more]

The present study was designed to evaluate the effect of hydroxyl propyl methyl cellulose (HPMC) on the complexation efficiency and dissolution of piperine (PPR) and β cyclodextrin (β CD) complex. The binary and ternary inclusion complexes were prepared using solvent evaporation and microwave irradiation methods. The samples were further evaluated for physicochemical evaluation, morphology, antimicrobial, and antioxidant activities. The binary and ternary samples showed high stability constant (Ks) value and complexation efficiency (CE). The dissolution study results revealed marked enhancement in the release of the binary inclusion complex and ternary inclusion complex compared to pure PPR. Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR), and molecular docking results confirm the complex formation. X-ray powder diffractometry (XRD) and scanning electron microscopy (SEM) data revealed modification in the structure of PPR. 2,2-diphenyl-1-picrylhydrazyl (DPPH) scaveng... [more]

The limited shelf life of carbon prepreg waste (CPW) from component manufacturing restricts its use as a composite reinforcement fibre on its own. However, CPW can be recycled with glass fibre (GF) reinforcement to develop a unique remediate material. Therefore, this study fabricated (1) a glass fibre-carbon prepreg waste reinforced polymer hybrid composite (GF-CPW-PP), (2) a polypropylene composite (PP), (3) a carbon prepreg waste reinforced composite (CPW-PP), and (4) a glass fibre reinforced composite (GF-PP) and reported their degradation and residual tension properties after immersion in water. The polymer hybrid composites were fabricated via extrusion technique with minimum reinforce glass-carbon prepreg waste content of 10 wt%. The immersion test was conducted at room temperature using distilled water. Moisture content and diffusion coefficient (DC) were determined based on water adsorption values recorded at 24-h intervals over a one-week period. The results indicated that GF-... [more]

Background: Despite the variety of treatment methods for wounds and scars after burns, there are still few effective preparations that can be used in a non-invasive therapy. Recent years have seen significant development of nanomedicine and nanotechnology in the treatment of infection in burn wounds. Proposal: The aim of this work was to develop a formula of a nanoemulsion gel for skin regeneration after burns, and to compare its rheological and sensory properties, as well as the effectiveness of post-burn skin regeneration with preparations available on the market. Methods: At the first stage of studies the composition and parameters of the preparation of sea buckthorn oil-based O/W (oil-in-water) nanoemulsion containing hyaluronic acid and aloe vera gel, as the active ingredients were optimized. Then, the nanoemulsion was added to the gel matrix composed of carbomer (1%) and water which resulted in receiving nanoemulgel. The physicochemical parameters of the obtained samples were cha... [more]

Solid-state recycling is a sustainable technique for recycling aluminium scrap, and the process before recycling is essential to control the physical properties of the product. In this work, the effect of the thermally-treated chips on the extrudate density was investigated. The aluminium chips were thermally-treated to enrich the alumina layer and reduce compaction pressure during chips compaction before recycled using direct hot extrusion. The chips that were transformed into compacted billets were extruded directly without melting and conducted according to 24 full factorial experimental design. The density test on the recycle extrudate found that the density variation ranged from 2724 to 2983 kg/m3. The ANOVA result showed that all factors investigated were statistically significant. The most significant factor was the preheating temperature, followed by extrusion ratio, chip treatment temperature, chip treatment time, and the interaction of chip treatment-time−extrusion ratio. The... [more]

In recent years, a strong interest has emerged in polysaccharide-hybrid composites and their potential applications, which have interesting functional and technological properties. This review summarizes and discusses the reported advantages and limitations of the functionalization of conventional and nonconventional polysaccharides by adding TiO2 nanoparticles as a reinforcement agent. Their effects on the mechanical, thermal, and UV-barrier properties as well as their water-resistance are discussed. In general, the polysaccharide−TiO2 hybrid materials showed improved physicochemical properties in a TiO2 content-dependent response. It showed antimicrobial activity against bacteria (gram-negative and gram-positive), yeasts, and molds with enhanced UV-protective effects for food and non-food packaging purposes. The reported applications of functionalized polysaccharide−TiO2 composites include photocatalysts (dye removal from aqueous media and water purification), biomedical (wound-heali... [more]

Nafion membrane with macropores is synthesized from silica crystal and composited with Pt nanoparticles to fabricate macroporous ionic polymer-metal composite (M-IPMC) actuator. M-IPMC shows highly dispersed small Pt nanoparticles on the porous walls of Nafion membrane. After the electromechanical performance test, M-IPMC actuator demonstrates a maximum displacement output of 19.8 mm and a maximum blocking force of 8.1 mN, far better than that of IPMC actuator without macroporous structure (9.6 mm and 2.8 mN) at low voltages (5.8−7.0 V). The good electromechanical performance can be attributed to interconnected macropores that can improve the charge transport during the actuation process and can allow the Pt nanoparticles to firmly adsorb, leading to a good electromechanical property.

The present study explores solid-state cryomilling for the compounding of green composites. Herein, wood plastic composites (WPCs) composed of sawdust (SD) and poly(ε-caprolactone) (PCL) with various compositions were prepared. Two compounding techniques, namely, extrusion and cryomilling, were utilized to prepare WPC raw material pellets and powders, respectively, for comparison purposes. Flat pressing was further utilized to prepare WPC films for testing. Morphological, structural, thermal, mechanical, and surface wettability properties were investigated. Results indicate the advantages of cryomilling in producing WPCs. Scanning electron microscopy (SEM) along with optical micrographs revealed well ground SD particles and uniform distribution in the PCL matrix. Tensile strength and elongation at break of the composites declined with increasing SD content, however, the modulus of elasticity significantly increased. Water contact angles averaged less than 90°, implying partial wetting.... [more]