Authors:Monika Božiková, Peter Hlaváč, Vlasta Vozárová, Zuzana Hlaváčová, Ľubomír Kubík, Peter Kotoulek, and Ján Brindza
Knowledge of bee products’ physical properties has a decisive importance for the monitoring of their quality. Thermophysical parameters are very important properties. Thermal conductivity and thermal diffusivity of selected bee products (honey, bee pollen and perga) were measured by two different methods. For identification of thermal conductivity and thermal diffusivity transient methods were used: Hot Wire (HW) and Dynamic Plane Source (DPS) method with an instrument Isomet 2104. The principle of measuring process is based on the analysis of timetemperature relation. In the first series of measurements thermal conductivity and diffusivity at constant laboratory temperature of 20 °C were measured. The second series was focused on identification of the changes in the thermophysical parameters during temperature stabilisation in the temperature range of 5–25 °C. For samples with constant temperature standard deviations and probable errors in % were calculated. For relations of thermal parameters to temperature graphical dependencies were obtained. Two different thermophysical methods were used for improvement of data reliability and data statistics.
Authors:Monika Furko, Zsolt Fogarassy, Katalin Balázsi, and Csaba Balázsi
]. The first applications of graphene were in the field of electronic devices, owing to its electronic characteristics [ 2 – 4 ]. Moreover, the graphene has more other interesting properties, such as high strength and stiffness, excellent thermal
Authors:Anikó Kovács, Katalin Badakné Kerti, and László Somogyi
confectionary systems. Here, we investigated differences in the texture properties, the viscosity and thermalproperties of the blends. Materials and methods Commercial sugar (sucrose), stevia and xylitol were used in this study. Palm oil was purchased from
Authors:I. Hanafi, A. Khamlichi, F. Mata Cabrera, E. Almansa, and A. Jabbouri
Non-reinforced and reinforced Poly-Ether-Ether-Ketone (PEEK) plastics have excellent mechanical and thermal properties. Machining is an efficient process that can be used to manufacture specific mechanical parts made from PEEK composites. Researchers have focused on improving the performance of machining operations with the aim of minimizing costs and improving quality of manufactured products, in order to get the best surface roughness and the minimum cutting force. The parameters evaluated are the cutting speed, the depth of cut and the feed rate. In this paper, the effect of the mentioned parameters on surface roughness and cutting force, in dry turning of reinforced PEEK with 30% of carbon fibers (PEEK CF30) using TiN coated cutting tools, is analyzed through using robust design techniques such as Taguchi's design method, signal-to-noise (S/N) ratio and statistical analysis tools such as Pareto-ANOVA. The obtained results have shown that Taguchi method and Pareto ANOVA are suitable for optimizing the cutting parameters with the minimum possible number of experiments, and the optimized process parameters were determined for surface roughness and cutting force criteria.
Six coloured and six non-coloured waxy rice varieties were analyzed by determining amylose, fat, and protein content, pasting, and thermal properties. Significant differences in protein content as well as pasting properties between coloured and non-coloured waxy rice were identified. It was demonstrated that protein may have a main influence on pasting and thermal properties of waxy rice. In addition, the optimal linear relationship between protein and pasting or thermal properties was found by combining RVA and DSC data using Principal component analysis (PCA). Typical indicators, which can classify coloured and non-coloured waxy rice, could be identified by Hierarchical cluster analysis (HCA). In pasting properties, trough and consistency viscosity were typical indicators; in thermal properties, enthalpy and stop temperature were typical indicators.