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[en] Highlights: • Drying kinetics characterization of granulated cork with a wide range of conditions. • Air stream temperature identified as dominant parameter in the drying experiments. • Characteristic drying rate curve with relevance for cork manufacturing industry. • Simple approach for optimal drying conditions selection after economical analysis. • Creating value from industrial bio-residues as a contribution to the circular economy. - Abstract: Granulated cork is a by-product of natural cork stoppers manufacturing which is incorporated into highly valued products such as agglomerated cork stoppers and expanded cork insulation. Prior to this, the cork granules must be dried. This work presents an experimental study for the characterization of wet granulated cork drying kinetics with different morphologies: a powder and granules with different sizes (2–2.8, 2.8–4 and 4–5.6 mm). A drying process with hot air stream flowing tangentially to the solid was used for a systematic analysis of the influence of air stream conditions (temperature and flowrate) on drying kinetics. Under these conditions, the influence of the stream temperature was much more relevant than its velocity with the drying time almost halving when the temperature rose from 35.0 °C to 56.5 °C. The drained humid solid with higher granulometry was dried entirely during a falling drying rate period. All others products presented a constant drying rate period before the falling drying rate period. The results revealed that the falling drying rate period is conditioned by water migration through the solid and presents a similar shape for all products. Thus, the behavior can be described by a single characteristic drying curve, allowing predicting drying rate as a function of the solid normalized humidity, despite the cork granules dimensions. This normalized curve is a useful tool for dryer equipment dimensioning in the cork manufacturing industry. To predict the time of drying for defined air drying conditions, a simple procedure was proposed using the characteristic drying rate obtained.
[en] In spite of the fact that gypsum is one of the most environmentally friendly binders, utilization of gypsum products is relatively narrow. The main problem of gypsum materials is their low resistance to the wet environment and radical decrease of mechanical properties with increasing moisture. The solution of the problem could be in use of composed gypsum-based binders, usually ternary, comprising gypsum, pozzolan and alkali activator of pozzolan reaction. These materials have a better moisture resistance and often also better mechanical properties. Paper provides literature survey of the possible compositions, properties and ways of utilization of the composed gypsum-based binders with latent hydraulic and pozzolan materials together with some results of present research performed by authors. (paper)
[en] Steel is a very versatile metallic material and widely used in modern life. Unfortunately, this material is prone to the phenomenon of corrosion and over time, can contribute to the failure of the product. In order to minimize this process, different types of coatings are used, due to their efficiency, economy and ease of application. The degradation of the film applied to steel by atmospheric agents is the result of the combination of various environmental factors, due to the highly destructive cyclic variations. The present work intends to determine the existence of significant statistical differences in the thickness distribution of coating in duplex systems (Fe/Zn/Paint), before and after conducting the humidity and temperature test with condensation in a constant atmosphere, from different tests carried out in the Stat graphics Centurion software. The influence of the preset conditions on the coating thickness before and after the test was demonstrated was demonstrated. These values were found in a suitable interval to guarantee the resistance to corrosion, not showing visible deterioration in the surface of the analyzed specimens.
[es]El acero es un material metálico muy versátil y ampliamente utilizado en la vida moderna. Desafortunadamente, este material está propenso al fenómeno de la corrosión y el pasar del tiempo, puede contribuir a la falla del producto. Para lograr minimizar este proceso se utilizan diferentes tipos de recubrimientos, debido a su eficacia, economía y facilidad de aplicación. La degradación de la película aplicada sobre el acero por los agentes atmosféricos es resultado de la combinación de diversos factores ambientales, debido a las variaciones cíclicas altamente destructivas. El presente trabajo pretende determinar la existencia de diferencias estadísticas significativas en las distribuciones del espesor de recubrimiento en sistemas dúplex (Fe/Zn/Pintura), antes y después de realizado el ensayo de humedad y temperatura con condensación en atmósfera constante, a partir de diferentes pruebas realizadas en el software Statgraphics Centurion. Se demostró la influencia de las condiciones prefijadas sobre el espesor de recubrimiento antes y después de realizado el ensayo. Dichos valores se encontraron en un intervalo adecuado para garantizar la resistencia a la corrosión, no evidenciándose deterioro visible en la superficie de las probetas analizadas.
[en] Few-layer black phosphorus (BP) is an emerging material of interest for applications in electronics. However, lack of ambient stability is hampering its incorporation in practical devices as it demands for an inert operating environment. Here, we study the individual effects of key environmental factors, such as temperature, light and humidity on the deterioration of BP. It is shown that humidity on its own does not cause material degradation. In fact, few-layer BP is employed as a recoverable humidity sensor. This study eliminates humidity as an active parameter in BP degradation. Hence, by simply isolating BP from light, its lifetime can be prolonged even in the presence of O2. As such, this study opens the pathway for devising new strategies for the practical implementation of BP. (paper)
[en] The effect of controlled humidity protection (CHP) on aircraft operated at Seosan area was studied. Aircraft with CHP showed less variation in relative humidity (RH) than non-CHP aircraft, but the RH of avionics bay of both cases were lower than external RH. Corrosion severity index (CSI) based on ISO 9223 was measured. The CSI of an aircraft shelter was moderate. Failure data were collected and analyzed for 93 line replaceable units (LRUs). Among 93 LRUs, 5 LRUs were analyzable, and only one LRU had a significantly higher mean time between failure (MTBF) due to CHP. As a conclusion, the effect of CHP on aircraft at Seosan was not an effective measure of corrosion protection.
[en] Tin selenide (SnSe) nanorods were synthesized using a one-step solvothermal route and their humidity sensing and photodetection performance at room temperature were investigated. The results depict that SnSe nanorod-based humidity and photosensors have good long-term stability, are highly sensitive and have fast response and recovery times. In the case of the humidity sensor it was observed that the resistance of the films decreased with increasing relative humidity (RH). The humidity sensing behaviors were investigated in the range 11–97% RH at room temperature. A response time of ∼68 s and recovery time of ∼149 s were observed for the humidity sensor. The photosensing behavior showed typical response /recovery times of ∼3 s with highly reproducible behavior. (paper)
[en] To further improve the application of cosmic-ray neutron sensor technology, the SWMCN Laboratory during the summer validated the footprint, effective depth and accuracy of the mobile or “backpack” version of the sensor. Through sixteen different calibrations for five research sites in Austria, located between 300 and 1700 m a.s.l., a comparison was made between the volumetric water content measured by the backpack and gravimetric measurements for different radii of influence. Results indicated similar outcomes based on a 0-75-meter footprint as compared to a 0-200 meter study suggesting that measurements by the mobile cosmic-ray neutron sensor have a footprint with a 200-meter radius (i.e. 20 hectares). The same data were also used to determine the effective depth, results showed that the effective depth is about 10 cm for volumetric water contents ranging between 30 and 60%.
[en] This study was conducted to determine the effects of different combinations of combined fertilizer dose applications on the turfgrass characteristics of a turf mixture in the ecological conditions of Sakarya/Pamukova in Turkey, between the years of 2013-2015. The research was conducted in the randomized block design with four replications. A cool season turf mixture consisting of 40% Lolium perenne L., cv. Integra, 25% Festuca rubra rubra L., cv. Eugene, 20% Festuca rubra commutata Gaud., cv. Survivor and 15% Poa pratensis L., cv. Evora was used as the material of the study. Such is a widely used mixture in the region. Nine different combination of NPK fertilizer doses (0-0-0, 5-2.5-2.5, 10-5-5, 15-7.5-7.5, 20-10-10, 25-12.5-12.5, 30-15-15, 35-17.5-17.5 and 40-20-20 g m-2 respectively) were tested. In this research; turf cover, weed invasion, uniformity, turf texture, color and turf quality were determined. At the end of the study, the most promising data were taken from the 30-15-15 g m-2 fertilizer dose compared to control. (author)
[en] Irradiation doses (2.00 and 2.50kGy) and Edible coating film Jojoba ( Simmondsiachinensis) oil 99.0% and polyvinyl alcohol (PVA) have been used for preserving the quality and safety of fresh fruit and vegetables. The objective of this research is to evaluate the effect of irradiation doses, jojoba oil and poly vinyl alcohol (PVA) on the shelf-life and quality of Le Conte pear fruits during cold storage at 0±1°C and relative humidity (RH) 85 – 90%. The results indicated that Edible coating film PVA, Jojoba oil 99.0% and irradiation 2.00kGy dose showed a significant loss of weight, firmness, total soluble solids, shelf life, peroxidase activity and soluble protein in (peel and core) compared to untreated (control) ones. The results showed also that coating PVA , Jojoba oil 99.0% and irradiation 2.00 kGy dose maintained the visual quality of Le Conte pear fruits during the storage time
[en] Peruíbe Black Mud (PBM) found in the city of Peruíbe in state of São Paulo, is known for its curative and anti-inflammatory properties. Considered as a material with high cation exchange capacity, microbiological analyzes revealed a large amount of sulfate reducing bacteria and high content of organic material from the biological-metabolic process. In order to provide data that may be useful to understand its therapeutic effects and secondly to certify its quality for use in medical treatments it is necessary to determine the presence of trace elements and minerals present in the different fractions of humic substances and, for this, the technique of neutron activation analysis (INAA) associated with gamma spectrometry was used. Results demonstrate that elements such as Cr and Zn may be concentrated in the humic fraction over the mineral fraction of the mud. (author)