Dietary administration of ewe diets with a distillate from rosemary leaves (Rosmarinus officinalis L.): Influence on lamb meat quality

The effect of including distilled rosemary leaf in the diet of pregnant ewes on subsequent lamb meat quality was studied. Thirty-six Segureña ewes were randomly assigned to three homogeneous groups. One group was fed a basal diet (BD) as control while the diet of the other two groups was modified by substituting 10% (R₁) and 20% (R₂) of the BD with a pellet made from 50% barley and 50% of distilled rosemary leaves (DRL). Meat spoilage (TVC, PSY and MYC), TBARS, CIELab coordinates and the sensory characteristics contribution of fresh lamb meat packed in MAP (70% O₂:30% CO₂) were analyzed on days 0, 7, 14 and 21. In general, R₁ and R₂ had higher a^* values, better scores for meat and fat colour (P < 0.05) and lower TBARS and rancid odour (P < 0.05), than the control samples. The total viable count was lower in meat DRL. No statistically significant differences were detected between the two treatments (10–20% DRL).     

Dye‐Doped Polyhedral Oligomeric Silsesquioxane (POSS)‐Modified Polymeric Matrices for Highly Efficient and Photostable Solid‐State Lasers

Here, the design, synthesis, and characterization of laser nanomaterials based on dye‐doped methyl methacrylate (MMA) crosslinked with octa(propyl‐methacrylate) polyhedral oligomeric silsesquioxane (8MMAPOSS) is reported in relation to their composition and structure. The influence of the silicon content on the laser action of the dye pyrromethene 567 (PM567) is analyzed in a systematic way by increasing the weight proportion of POSS from 1 to 50%. The influence of the inorganic network structure is studied by replacing the 8MMAPOSS comonomer by both the monofunctionalized heptaisobutyl‐methacryl‐POSS (1MMAPOSS), which defines the nanostructured linear network with the POSS cages appearing as pendant groups of the polymeric chains, and also by a new 8‐hydrogenated POSS incorporated as additive to the polymeric matrices. The new materials exhibit enhanced thermal, optical, and mechanical properties with respect to the pure organic polymers. The organization of the molecular units in these nanomaterials is studied through a structural analysis by solid‐state NMR. The domain size of the dispersed phase assures a homogeneous distribution of POSS into the polymer, thus, a continuous phase corresponding to the organic matrix incorporates these nanometer‐sized POSS crosslinkers at a molecular level, in agreement with the transparency of the samples. The silicon–oxygen core framework has to be covalently bonded into the polymer backbone instead of being a simple additive and both the silica content and crosslinked degree exhibit a critical influence on the laser action.     

Mullite–zirconia–zircon composites: Properties and thermal shock resistance

In the refractory field mullite and zirconia are the basis of materials used in the glass industry or when high chemical stability and corrosion resistance are necessary. In this work various mullite–zirconia/zircon compositions were investigated to improve the thermal shock (TS) resistance of dense composites produced by slip casting and sintering at 1600 °C. Zircon (SiZrO₄) acts as bonding phase and its thermal decomposition adds zirconia and silica to the material. Resultant composites were characterized by density and dilatometric measurements, XRD and SEM techniques. TS behavior was tested by quenching in water with quenching temperature differentials ΔT from 400 to 1200 °C. The degree of damage after the TS was experimentally evaluated through the variation of the elastic modulus E which is measured by the excitation technique. The severity of the TS test and the effect of the number of thermal cycles on E for each ΔT employed were determined.The tested materials retained their original mechanical properties for temperatures below a critical temperature ΔT_c near 600 °C. Materials quenched from ΔT of 1000 °C showed as much as 30% reduction in E indicating the important microstructure damage. The TS resistance improved with increasing zircon addition to 35 wt% in agreement with the behavior predicted from R parameter for crack initiation.     

Retention of cobalt on a humin derived from brown coal

In this work, the retention of cobalt on a humin (HU) derived from a brown coal is studied. Through a systematic and coordinated investigation of the behavior of the metal ions in solution (speciation diagrams as a function of pH) and their adsorption and precipitation processes with reactive functional groups of the solid (sorption isotherms), the interactions of different Co(II) species with HU are probed. To further confirm the nature of these interactions, the complementary spectroscopic techniques of FTIR, Raman microspectroscopy, UV-visible absorption and XRD are employed. Molecular modeling techniques are used to gain information about the stability of different Co(II) species as a function of pH, as well as the stability of Co(II) species complexed with benzoic acid, a common surface component of humic substances. It is found that the selectivity that humin has for different Co(II) species, as well as the amount of Co(II) that it can retain, are both highly dependent on pH. Through Raman microspectroscopy measurements, the presence and location of Co(OH)(2) precipitates on the surface of HU is confirmed.     

Giant electric-field-induced strains in lead-free ceramics for actuator applications – status and perspective

In response to the current environmental regulations against the use of lead in daily electronic devices, a number of investigations have been performed worldwide in search for alternative piezoelectric ceramics that can replace the market-dominating lead-based ones, representatively Pb(Zr _x Ti_1-x )O₃ (PZT)-based solid solutions. Selected systems of potential importance such as chemically modified and/or crystallographically textured (K, Na)NbO₃ and (Bi_1/2Na_1/2)TiO₃-based solid solutions have been developed. Nevertheless, only few achievements have so far been introduced to the marketplace. A recent discovery has greatly extended our tool box for material design by furnishing (Bi_1/2Na_1/2)TiO₃-based ceramics with a reversible phase transition between an ergodic relaxor state and a ferroelectric with the application of electric field. This paired the piezoelectric effect with a strain-generating phase transition and extended opportunities for actuator applications in a completely new manner. In this contribution, we will present the status and perspectives of this new class of actuator ceramics, aiming at covering a wide spectrum of topics, i.e., from fundamentals to practice.     

Microbial, physical-chemical and sensory spoilage during the refrigerated storage of cooked pork loin processed by the sous vide method

The aim was to study spoilage during the refrigerated storage of cooked pork loin processed by the sous vide method. Samples were packaged under vacuum into polyamide-polypropylene pouches, cooked at an oven temperature/time of 70 °C/12 h, chilled at 3 °C and stored at 2 °C for 0, 5 or 10 weeks. Microbial (psychrotrophs, lactic acid bacteria, Enterobacteriaceae, moulds and yeasts), physical–chemical (pH, water activity, TBARS, acidity, L^*a^*b^* colour, texture profile analysis and shear force) and sensory (appearance, odour, flavour, texture and acceptance) parameters were determined. The results showed that sensory spoilage preceded microbiological spoilage of sous vide pork loin. Counts bellow 1 log cfu/g of psychrotrophs, anaerobic psychrotrophs, Enterobacteriaceae and lactic acid bacteria were detected in any control week, while moderate counts (2–3 log cfu/g) of moulds and yeasts were found. Minor changes in water activity, lipid oxidation, CIELab colour, hardness, cohesiveness or gumminess were associated with spoilage of pork loin, only decreases of lactic acid, springiness and shear force were observed. The pork loin was unacceptable after 10 weeks. This loss of acceptance was mainly due to the deterioration of meaty flavour and odour, although the loss of appearance, juiciness and firmness also contributed. Moderate warmed-over and rancidity were detected. The sensory analysis was the most effective method for determining the shelf life of the sous vide pork-based dishes.     

Effects in ewe diet of rosemary by-product on lipid oxidation and the eating quality of cooked lamb under retail display conditions

Distilled dietary rosemary leaf (DRL) was tested to prevent lipid oxidation and sensory deterioration of cooked lamb under retail display conditions. Pregnant sheep were fed with a basal diet supplemented by 0%, 10% and 20% DRL. Cooked lamb fillets were stored for 0, 2 or 4 days at a temperature of 4 °C in a display cabinet and re-heated, simulating catering practices. The cooked lamb suffered rapid lipid oxidation and odour and flavour spoilage associated with slight rancidity and warmed-over flavour, and, to a lesser extent, with loss of colour and juiciness. DRL feeding delayed lipid oxidation measured as TBARS and volatile compounds, this being more effective in the first two days of storage. 10% and 20% of DRL provided equal antioxidant capacity. However, DRL feeding hardly prevented sensory deterioration, although incipient rancidity was delayed. Feeding DRL to ewes contributed to extend the shelf life of cooked lamb under retail display conditions.     

Thermal-stability of electric field-induced strain and energy storage density in Nb-doped BNKT-ST piezoceramics

In this work, the relationship between the structural mechanisms and macroscopic electrical properties of the Nb-modified 0.96(Bi_0.5Na_0.84K_0.16TiO₃)–0.04SrTiO₃ (BNKT–ST) system were elucidated by using temperature dependent and in situ synchrotron X-ray diffraction (XRD) techniques. For the composition x?=?0.0175, a large-signal piezoelectric coefficient (S_max/E_max?=?d₃₃*) of 735 pm?V^?1 at 6?kV mm^?1 was observed at room temperature. Interestingly, at a higher temperature of 110?°C, the sample still showed a large d₃₃* of 570 pm V^?1. Furthermore, the temperature-invariant electrostrictive coefficient for this sample was found to be 0.0285?m⁴?C^?2 over the temperature range of 25–170?°C. Moreover, the energy density for x?=?0.030 sample was ～1.0?J?cm^?3 with an energy storage efficiency of ?70% in the temperature range of 25–135?°C. These results suggest that the synthesized Nb-modified BNKT–ST system is promising for the design of ceramic actuators as well as capacitor applications.     

New cardo silylated poly(azomethine)s containing 9,9′‐diphenylfluorene units as materials with Brønsted acid‐dependent fluorescence

Aromatic poly(azomethine)s have been studied due to their attractive properties such as high thermal stability, semiconducting behavior and the ability to coordinate species with their imine units (C?N). In this paper, the synthesis and characterization of two novel silylated poly(azomethine)s containing cardo units are reported. These materials were highly soluble in organic solvents such as chloroform and m‐cresol and were thermally stable, and PAzMC1 exhibited a high glass transition temperature value (287 °C), while that for PAzMC2 was not observed. UV–visible spectrophotometry revealed absorption bands related to the aromatic backbone of both PAzMCs, 300–285 nm in tetrahydrofuran and 310–301 nm in dimethylsulfoxide, and bands attributed to the conjugated imine unit at around 350 nm. In order to investigate the phenomenon of the emission of fluorescence promoted by dopant agents with regard to potential optoelectronic applications, the materials were doped with H₂SO₄ and their optical and electrochemical properties investigated. Thus, the absorption band of the imine group was suppressed due to the nitrogen atoms being protonated. Fluorescence spectroscopy analysis developed in dilute solutions of polymers showed no emission from the undoped polymers, whereas the acid‐doped species emitted fluorescence in the UV and violet regions (322 nm). Cyclic voltammetry measurements were carried out and HOMO–LUMO energies were estimated. This study provides a starting point for the development of new poly(azomethine)s with doping‐dependent emission. © 2019 Society of Chemical Industry     

The use of joint coordinates to monitor patients in a movement-based interaction system

Universal Access in the Information Society - Movement-based interaction has brought about new possibilities in healthcare environments. Concretely, rehabilitation therapies represent an adequate...