• Magnetic biopsy of the human liver
• Method and device for the measurement of thermal resistance of aluminum heat sinks

Result 1:  Magnetic biopsy of the human liver

Projects: APVV-51-059005 a VEGA 2/7084/27.

Authors:  J. Maňka, I. Šimáček, M. Škrátek, P. Jurdák, K. Jurča

A SQUID-biosusceptometer has been realized and a noninvasive method of the iron (Fe) content measurement in the liver has been examined. By measurement of responses to AC magnetic field applied to the abdoment of tested person it is possible directly to determine the Fe concentration in the liver tissue. The way of measured results correction depending on size, shape and position of the liver related to the sensor has been designed. The device basic sensitivity and intervals of 95% reliability for mean and individual value of Fe concentration determination have been defined. Based on achieved sensitivity and statistically processed data the biosusceptometer is able to measure the Fe content in the liver of patients with higher than normal Fe level (concentration higher than 1.2 miligram of iron in 1 gram of the liver tissue). The device is applicable for diagnostics of primary haemochromatosis, haemosiderosis and for noninvasive monitoring of risk of beginning of the diabetes, cirhosis and other diseases. The measuring method has been proved on models and experimentally tested on four patients. The results were in a good agreement, they correlated (r = 0,9) with the values of Fe concentration obtained by MRI examinations of these persons livers in the Radiodiagnostic Clinic, Academician Ladislav Derer Hospital, Bratislava.

The result has been achieved in cooperation with Faculty of Medicine, Comenius University, Bratislava.

Publications:

• Jurdák, Peter - Kopáni, Martin - Šimáček, Ivan - Maňka, Ján - Škrátek, Martin: Magnetometric Measurements of Ferro- or Ferrimagnetic Microparticles Dispersed in Medium Approximating the Intracellular Environment. In Jian-Ping Wang Nanoscale Magnetic Materials and Applications, Mater. Res. Soc. Symp. Proc. Volume 1032E, Warrendale, PA, 2008, 1032-I04-19.ŠKRÁTEK, Martin - JURDÁK, Peter - ŠIMÁČEK, Ivan:. Modelové merania obsahu železa v pečeni. In Trends in Biomedical Engineering, ISBN 978-80-227-3105-8, 2009.
• I. Šimáček, P. Jurdák, J. Maňka and M. Škrátek: Accuracy of the measurement with the second order axial gradiometer. In MEASUREMENT SCIENCE REVIEW, Volume 9, No. 6, 200, pp 179-182.

Result 2: Method and device for the measurement of thermal resistance of aluminum heat sinks

Projects: -

Authors:  M. Hain, V. Jacko, J. Bartl

Thermal resistance of heat sinks used in electronic and electrical industry is an important parameter necessary for the efficient use of the heat sinks by dissipating the waste heat in electronic devices. The requirement to design measurement method, develop a measuring device and make measurements of thermal resistance of selected aluminum heat sinks was addressed to the Institute of Measurement Science from the biggest manufacturer of heat sinks in Slovakia, company GAMAalumínium, Ltd.  Žiar nad Hronom.

Within the project a methodology for measurement of the thermal resistance of heat sinks was designed. Developed measuring system is composed from the data logger, temperature sensors type PT100 and thermocouples type K, the heat source, specific measurement software developed at IMS SAS, personal computer, DC voltage source and measuring stand. The system is designed for the measurement of thermal resistance of heat sinks in the dissipation range from 0 to 500 W. The measurement is automated and measured data are transmitted in real time from the measuring program to an Excel spreadsheet, where are further processed and presented in numerical and graphical form.

A detailed analysis of sources of measurement uncertainty in the measurement chain (indirect method of measurement) was performed and the type B uncertainty was evaluated.
The analysis of measurement uncertainties of type A was performed and then the combined relative expanded uncertainty of measurement of thermal resistance was evaluated U=0,7 % (ku=2).

User of the result: GAMAalumínium s.r.o., Žiar nad Hronom

 

Figure: Measured dependence of the thermal resistance of the cooler KE 215 on the dissipated power.