The effects of tannins on adhesion strength and surface roughness of varnished wood after accelerated weathering

This study evaluated the effect of accelerated weathering on the adhesion strength and surface roughness of beech wood (Fagus orientalis) treated with mimosa and quebracho extracts and coated with polyurethane, water-based, and cellulosic varnishes. Untreated beech wood blocks and beech wood blocks treated with Tanalith-E were used as control samples. Test samples were exposed to accelerated weathering processes of 100 and 300 h. According to the test results, the mean adhesion strength of the wood samples impregnated with mimosa and quebracho tannins decreased by a maximum of 20%, while increases in the mean surface roughness (R _a) were detected. The highest adhesion strength and lowest mean surface roughness were obtained with polyurethane varnish. Moreover, the mean adhesion strength increased with the accelerated weathering up to 100 h and then decreased thereafter. As a result of the weathering process, the mean surface roughness increased and was thus negatively affected.     

Transferrin-Decorated Niosomes with Integrated InP/ZnS Quantum Dots and Magnetic Iron Oxide Nanoparticles: Dual Targeting and Imaging of Glioma

The development of multifunctional nanoscale systems that can mediate efficient tumor targeting, together with high cellular internalization, is crucial for the diagnosis of glioma. The combination of imaging agents into one platform provides dual imaging and allows further surface modification with targeting ligands for specific glioma detection. Herein, transferrin (Tf)-decorated niosomes with integrated magnetic iron oxide nanoparticles (MIONs) and quantum dots (QDs) were formulated (PEGNIO/QDs/MIONs/Tf) for efficient imaging of glioma, supported by magnetic and active targeting. Transmission electron microscopy confirmed the complete co-encapsulation of MIONs and QDs in the niosomes. Flow cytometry analysis demonstrated enhanced cellular uptake of the niosomal formulation by glioma cells. In vitro imaging studies showed that PEGNIO/QDs/MIONs/Tf produces an obvious negative-contrast enhancement effect on glioma cells by magnetic resonance imaging (MRI) and also improved fluorescence intensity under fluorescence microscopy. This novel platform represents the first niosome-based system which combines magnetic nanoparticles and QDs, and has application potential in dual-targeted imaging of glioma.     

Effects of crushed clay brick aggregate on mortar durability

This paper reports an experimental study that aimed to investigate the effects of recycled clay brick, used as a part of fine aggregate, on mortar durability. The brick, in crushed form, was from a local brick manufacturer that salvages its off-standard products. It was used to replace 10% and 20% (by weight) of the river sand in mortar. Effects of the brick replacement on the mortar flow, compressive strength, shrinkage, freeze–thaw resistance, and alkali–silica reaction potential were investigated. The results showed that as the brick replacement level increased, the mortar flowability reduced. The 10% and 20% brick replacements had no negative effect on the mortar compressive strength and very limited effect on the mortar shrinkage. The freeze–thaw resistance of the mortar was improved by the brick replacement. However, the use of crushed brick as aggregate appeared not to reduce potential alkali–silica reaction. The microscopy study revealed the alkali–silica reaction product and associated cracking in the mortar. Additional study indicated that the brick aggregate used in the study had pessimum proportion, 30%, for the alkali–silica reaction expansion.     

Multi-verse optimization algorithm- and salp swarm optimization algorithm-based optimization of multilevel inverters

Neural Computing and Applications - Renewable energy sources are installed into both distribution and transmission grids more and more with the introduction of smart grid concept. Hence, efficient...     

Optimization of EDGE terminal power amplifiers using memoryless digital predistortion

This paper describes a lookup-table (LUT)-based digital predistortion system usable for enhanced data for global system for mobile evolution (EDGE) handset transmitters. The system is memoryless and capable of improving average efficiency and performance in terms of the leakage power at offset frequencies and error vector magnitude. The obtainable efficiency at maximum linear output power is comparable, but at backoffs superior to commercial EDGE power amplifiers (PAs). Minimum system requirements on word length and LUT size have been investigated, which shows that a LUT having approximately 500 coefficients and a system word length of 13 bits are sufficient for EDGE. The proposed system is simple compared to basestation implementations comprising PA memory compensation and can be easily implemented in handsets in order to improve the overall system performance. The effects of antenna mismatch on system performance have been investigated     

An in vitro evaluation of Genipin-crosslinked and Hypericum perforatum incorporated novel membranes for skin tissue engineering applications

Incorporating medicinal plant extracts in membranes have a great potential as scaffolds for tissue engineering applications or vehicles for delivering therapeutic agents. Herein, Hypericum perforatum oil (0.25, 0.50, % vol/vol) loaded membranes were developed with Polyvinyl alcohol and chitosan polymer, where Genipin works as a chemical crosslinker to obtain a wound dressing material with acceptable characterization properties. Chemical groups, surface morphology, water uptake capacity, water vapor permeability rate, hydrophilicity, and mechanical properties of membranes were thoroughly investigated. Increasing oil concentration had a significant effect on the water uptake, surface morphology. and water vapor permeability rate of the membranes. Cytocompatibility of the membrane was also investigated with mouse embryonic fibroblasts (MEF) by 3-(4,5-dimethylthiazoyl-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for direct and indirect cell culture studies. SEM was used to investigate the cell morphology on the membranes. The MTT assay findings prove that Genipin crosslinked H. perforatum oil loaded scaffolds are highly biocompatible and enhance the adhesion and proliferation of MEF cells. In addition to this, the genotoxicity test was performed to show DNA fragmentation. Results showed that the H. perforatum oil loaded polyvinyl alcohol-chitosan membrane presents suitable properties for potential skin tissue engineering applications.     

A Novel Approach to Limit Chemical Deterioration of Gilthead Sea Bream (Sparus aurata) Fillets: Coating with Electrospun Nanofibers as Characterized by Molecular,Thermal, and Microstructural Properties

Coating of sea bream fillets with thymol loaded chitosan based electrospun nanofibers (TLCN) and chitosan based nanafibers (CN) has been presented a novel approach to delay chemical deterioration. We assessed CN and TLCN with respect of scanting of total volatile basic nitrogen (TVBN), trimethylamine (TMA), thiobarbituric acid (TBA) deterioration during cold storage condition. Electrospinning process was applied to obtain TLCN and CN. Both of nanofibers obtained from biopolymer and bioactive material were cylindrical, smooth, beadless. Thermal, molecular, zeta potential (ZP), and surface properties of the groups were investigated, revealing that CN indicated molecular interactions with thymol in nanofibers, reduce in physical properties of these structures, thermal decomposition (an alteration in mass of CN and TLCN at temperatures below 190 °C, corresponding to 20.53% and 19.97%, respectively) and also dispersion stabilities (ζ potential) of CN and TLCN were determined 33.68 ± 3.35 and 21.85 ± 1.96 mV, respectively. TVBN and TMA stability analyses demonstrated that CN and TLCN were both effective in delaying chemical deterioration of fish fillets, furthermore TLCN was more effective against chemical deterioration. TBA analyses results of fish fillets indicated that CN and TLCN delayed rancidity in fish meat as compared to control group samples. The presented study results suggested that coating of the sea bream fillets with CN and TLCN would be a promising approach to delay the chemical deterioration of fish fillets.     

New perylene derivative dyes for dye-sensitized solar cells

We have studied the influence of the spacer alkyl chain length of perylenemonoimide (PMI) dyes on the device performance in dye-sensitized solar cells (DSSCs). We observed that the dyes with longer and brunched alkyl chains exhibit higher efficiencies in DSSCs. In line with these statements we now report the highest efficiency obtained under standard conditions for a perylene imide derivative with PMI-DA1 that performs 300 mV open circuit voltage, 9.79 mA/cm² short-circuit current and 1.61% overall conversion efficiency.     

Biohydrogen and 5-aminolevulinic acid production from waste barley by Rhodobacter sphaeroides O.U.001 in a biorefinery concept

The production of biohydrogen and 5-aminolevulinic acid (5-ALA) by Rhodobacter sphaeroides O.U.001 was investigated in a biorefinery concept. Waste barley was used as a substrate after acid hydrolysis. The hydrolysate was analyzed in terms of its total simple sugar, organic acid, ammonium, element and total phenol contents. Four different growth media having 5 g/L, 7 g/L, 9 g/L and 11 g/L sugar content were prepared using the waste barley hydrolysate to produce biohydrogen and 5-ALA. The increased sugar concentrations resulted in higher cell density and hydrogen accumulation. Accordingly, the highest cell density (OD₆₆₀: 1.78) and hydrogen production (0.4 L H₂/L culture) were observed in the 11 g/L sugar-containing medium. A 67.4 μM 5-ALA was produced upon vitamin B₁₂ and levulinic acid additions. These results showed that waste barley can be used as a substrate for R. sphaeroides for biohydrogen and 5-ALA production within a biorefinery concept.