Design and verification of thermostat with peltier thermoelectric modules
In the paper we deal with design, modeling and verification of thermostat with particularly thermally insulated chamber, based on Peltier thermoelectric modules (elements). A prototype of the designed thermostat has been realized. Parameters of the regulated system were obtained experimentally. We have developed the reliable model of the complete thermostat with the PSD regulation in the Matlab environment, as well. The model helps to optimize the parameters of the regulator according to desired temperature profiles inside the chamber. Measurements show a good agreement between the model and realized prototype of the thermostat.
RT-Lab - the Equipment for Measuring Thermophysical Properties by Transient Methods
The paper introduces novel equipment RT-Lab for measuring thermophysical properties of various materials by means of the transient methods we have developed in our laboratories. The entire measuring process can be realized by the RT-Lab. The equipment can operate in several measuring regimes and different transient methods. Functionality of the RT-Lab was verified by measurement of the thermophysical properties of the standard material BK7 using pulse transient method. The RT-Lab replaced the electronic unit RT 1.02 that for its operation required two additional expensive equipments, the programmable power source (KEPCO ABC 15-7 DM) and the precise multimeter (KEITHLEY-2010).
Exopolysaccharide biosynthesis and related enzyme activities of the medicinal fungus, Ganoderma lucidum, grown on lactose in a bioreactor
Exopolysaccharide (EPS) production and biosynthesis were studied in Ganoderma lucidum, a fungus used in traditional Chinese medicine, grown with lactose in a bioreactor. β-Galactosidase activity, which implies the existence of a lactose permease system, was induced by lactose. Lactose feeding also increased α-phosphoglucomutase activity and EPS accumulation but decreased phosphoglucose isomerase activity and lactate concentration in the culture broth. A maximum cell density of 22 g l−1 and EPS at 1.25 g l−1 were obtained in fed-batch bioreactor culture.