Surface properties of impregnated and varnished Scots pine wood after accelerated weathering

In this study, the effect of accelerated weathering on the surface properties of Scots pine specimens impregnated with wolmanit‐CB, tanalith‐E, and adolit‐KD5 and coated with synthetic and polyurethane varnishes was investigated by measuring surface hardness, glossiness, and colour. Results showed that weathering caused an increase in the hardness of impregnated and varnished specimens, while it caused a decrease in the glossiness of specimens. Surfaces became rougher and darker after weathering in comparison with the initial surfaces of wood specimens. Positive values of the chromatic coordinates indicated that the wood surfaces changed from their original colour to a reddish and yellowish colour. The highest colour change was detected in the specimens coated with polyurethane varnish alone. Both copper‐based wood preservative treatment and varnish coating improved the surface properties of specimens in comparison with the surface properties observed on specimens coated with varnish alone.     

Strength estimation of unisothermally cured concretes with matrices

A new matrix method was developed for estimating the strength of in situ concrete exposed to unisothermal curing conditions. The model considers effect of various curing temperatures occurred at different ages of concrete on strength development of concrete. The cross-over effects on later age concrete strength due to hot or cold weather conditions in early-ages of concrete were also considered. The model ensures precise strength estimations with error percentages below 7%. The time required for form removal of concrete can be determined by the method.     

Changes during fishing season in the fat content and fatty acid profile of edible muscle,liver and gonads of anchovy (Engraulis encrasicolus) caught in the Turkish Black Sea

This study aimed to determine the fat content and fatty acid (FA) composition of anchovy (Engraulis encrasicolus, Linnaeus, 1758) in their edible muscle, liver and gonad during the catching season (between September 2008 and April 2009) in The Black Sea Region, Turkey. The most abundant FAs in all samples were palmitic acid (ranged as 15.93–27.34%) amongst saturated fatty acids (SFAs), oleic acid (10.72–21.37%) amongst monounsaturated fatty acids, eicosapentaenoic acid (EPA) (5.28–14.11%) and docosahexaenoic acid (DHA) (9.83–22.34%) amongst polyunsaturated fatty acids (PUFAs). At the beginning of winter, significant increase in edible muscle and liver’s PUFAs and ∑n3/∑n6 were observed (P < 0.05). The highest contents of ∑PUFAs for muscle and liver were observed in January as 38.52% and 38.82%, respectively, while highest n3/n6 ratios were found in April as 10.13% for muscle and in January for liver samples as 9.15%. This study indicates that anchovy is a good nutritional source for human consumption with high contents of omega 3 fatty acids, particularly during winter. In November, about 130 g of anchovy edible meat is found to be in the satisfactory level for EPA + DHA according to the recommended weekly requirement.     

Effect of boron compounds on fire protection properties of epoxy based intumescent coating

The aim of this study was to investigate the effect of boron compounds on fire protection properties of intumescent coating based on ammonium polyphosphate (APP). Three kinds of boron compounds namely boric acid (BA), zinc borate (ZB) and melamine borate (MB) were used. Total amount of flame retardant additive was kept constant at 30 wt%, and boron compounds were used at three concentrations of 1, 3 and 5 wt%. Thermogravimetric analysis (TGA), Attenuated total reflectance–Fourier transform infrared spectroscopy (ATR‐FTIR) and fire test were conducted for the determining the fire performance of intumescent coating. According to fire test results, BA and MB showed synergistic effect at 1 wt% loading. ZB showed antagonistic effect at all concentrations. Fire protection effect of intumescent coating decreased as the added amount of boron compound increased regardless of boron compound type because of suppression of intumescence. Copyright © 2016 John Wiley & Sons, Ltd.     

Stability of black carrot anthocyanins in various fruit juices and nectars

Fruit juices (apple, grape, orange, grapefruit, tangerine and lemon) and nectars (apricot, peach and pineapple) were coloured with black carrot juice concentrate and stability of black carrot anthocyanins in these matrices was studied during heating at 70–90 °C and storage at 4–37 °C. Anthocyanin degradation, in all coloured juices and nectars, followed first-order reaction kinetics. During heating, black carrot anthocyanins in apple and grape juices showed higher stability than those in citrus juices at 70 and 80 °C. High stability was also obtained for the anthocyanins in peach and apricot nectars at these temperatures. Black carrot anthocyanins were the least stable in orange juice during both heating and storage. During storage, degradation of anthocyanins was very fast at 37 °C, especially in pineapple nectar. Refrigerated storage (4 °C) markedly increased the stability in all samples. Activation energies for the degradation of black carrot anthocyanins in coloured juices and nectars ranged from 42.1 to 75.8 kJ mol⁻¹ at 70–90 °C and 65.9–94.7 kJ mol⁻¹ at 4–37 °C.     

Polysulfone/Clay Nanocomposites by in situ Photoinduced Crosslinking Polymerization

PSU/MMT nanocomposites are prepared by dispersing MMT nanolayers in a PSU matrix via in situ photoinduced crosslinking polymerization. Intercalated methacrylate‐functionalized MMT and polysulfone dimethacrylate macromonomer are synthesized independently by esterification. In situ photoinduced crosslinking of the intercalated monomer and the PSU macromonomer in the silicate layers leads to nanocomposites that are formed by individually dispersing inorganic silica nanolayers in the polymer matrix. The morphology of the nanocomposites is investigated by XRD and TEM, which suggests the random dispersion of silicate layers in the PSU matrix. TGA results confirm that the thermal stability and char yield of PSU/MMT nanocomposites increases with the increase of clay loading.

     

The Annealing Effects in the Iron-Based Superconductor FeTe0.8Se0.2 Prepared by the Self-Flux Method

FeTe_0.8Se_0.2 single crystals as-cast and post-annealed were prepared by the self-flux method. We have investigated the structural properties of samples by using the XRD, scanning electron microscope (SEM), energy dispersive X-ray (EDX), and magnetic techniques. The SEM results clearly demonstrate that Te ions are quite well substituted for Se ions in the FeSe lattice for the samples. From the XRD and EDX spectra of the both samples, it has been concluded that the post-annealing causes no change in the tetragonal structure of FeTe_0.8Se_0.2. According to M–H measurements, the perfect diamagnetism has been observed only in low field at 5 and 10 K temperatures. The trend of the magnetization versus temperature curves, measured under a magnetic field of 10 Oe, also support our conclusion about diamagnetic contribution in FeTe_0.8Se_0.2 single crystal explored in this study. The as-cast and post-annealed samples show the onset of diamagnetism at temperatures, \(T_{\mathrm {c.on}}^{\text {mag}}\) , 12.45 and 13.27 K, respectively. In addition, those curves indicate that the high field value and some impurities reveal ferromagnetic interactions.     

Effect of (Ta/Nb) co-doping on the magnetoresistivity and flux pinning energy of the BPSCCO superconductors

In the present work, the effect of co-doping of Ta and Nb with nominal composition of (BiPb)₂Ta_xSr₂Ca₃Cu_4?yNb_yO_12+δ where x = 0.1 and y = 0.0, 0.025, 0.05, 0.075, and 0.1 were investigated. The samples were prepared by using the well-known conventional standard solid-state reaction method. The magnetoresistance measurements were studied for different values of the applied magnetic field. The activation energies, irreversibility fields (H _irr ), upper critical fields (H _c2 ) and coherence lengths at 0 K (ζ(0)) were calculated from the resistivity versus temperature (ρ-T) curves, under DC magnetic fields up to 6 T. The thermally activated flux flow (TAFF) model has been applied in order to calculate the flux pinning energies. The results have shown that the upper critical magnetic field, H _c2 (0), and the flux pinning energies vary from ~113 to 74 T and ~384 to 101 meV at 0 T, with the Nb-content, respectively.     

Thermal Stabilities of Peroxidases from Fresh Pinto Beans

Heat stabilities of crude and partially purified soluble (SPOX), ionically bound (IPOX) and total peroxidase (TPOX) from fresh pinto beans were investigated at 55–90°C. Heat inactivation of peroxidase (POX) followed first-order reaction kinetics. Each inactivation curve consisted of two linear parts: initial rapid inactivation (heat-labile) followed by slower inactivation (heat-stable). IPOX showed activation during heat treatment with a highly heat-stable isoenzyme (D₉₀=40 min) which was more heat-stable than SPOX. Activation energies for heat-stable parts of crude IPOX and SPOX were, respectively, 12.1 and 36.4 kcalmol-1 with z values 45.4 and 14.1C°. Heat stable SPOX isoenzymes (D₇₀=22.6) were obtained by 65–95% (NH₄)₂SO₄ precipitation from crude SPOX. Two POX fractions (F1 and F2) were separated from TPOX by ion-exchange chromatography.