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Nanofluids as a quite new group of nanomaterials are very promising. A great potential of nanofluids was noted in second half of twentieth century and it was related with high increase of thermal conductivity. The most favourable effects of using nanofluids can be achieved in heat transfer systems, but also in other branch of industry like car, energy, and mining industry, even biomedicine industry. This paper presents results of experimental investigation of electrical conductivity of nanosuspension containing indium oxide nanoparticles dispersed in ethylene glycol. Five samples with volume fraction in the range 0.0016-0.0081 were prepared using two-step method. After preparation, all samples were impatiently investigated in controlled temperatures in the range from 298.15 K to 333.15 K. Measurement were conducted using conductivity meter MultiLine 3630 working with conductivity probe LR925/01 (WTW GmbH, Weilheim, Germany). Obtained results indicate that changes in volume concentration and temperature have strong impact on electrical conductivity of In2O3-EG nanofluids.

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Nanofluids, which are suspensions of nanoparticles, are interesting engineering materials, which might find numerous applications in industry. Unfortunately, there is no coherent theoretical model describing viscosity of nanofluids and further experimental and theoretical studies of this issue should be performed. This paper makes a contribution to this field. Dynamic viscosity of ethylene glycol based nanofluids containing indium oxide nanoparticles was measured in shear rate range from 10 s −1 to 1000 s −1 at constant temperature. It was presented that those materials exhibit Newtonian nature. Viscosity increases with the volume fraction of particles in nanofluids, and the Krieger-Dougherty equation could be applied to describe this increase. Additionally, a dependence of viscosity on temperature was examined in the range from 278.15 K to 338.15 K with constant shear rate 100 s −1 .

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We are constantly watching the growth of mobile phone users around the world. This causes interest in the issue of the influence of electromagnetic radiation on the human body. The sources of electromagnetic fields are among others mobile telephony. Mobile telephony consists of two basic elements: telephones (terminals) and base stations. Specific Absorption Rate (SAR) means the unit of amount of radiofrequency energy absorbed by the human body when using a mobile phone. The aim of the study was to measure the intensity of the electric field of the radio wave emitted by selected mobile phones. The measurements were carried out in the Radiation Measurement Laboratory at the Provincial Sanitary-Epidemiological Station in Rzeszów. Measurements were made for devices operating in different data transmission systems operating in certain frequency bands. The electric field of the electromagnetic field was measured using an wide field electromagnetic field measuring device type NBM-550 No. B-0240 with EF-1891 type probe. Measurements were made for devices with switched on and off data transmission at the time of receipt and during signaling. In the following sections describe mobile telephony and the basic characteristics of the mobile phone technology. The last part presents the way of making measurements and presentation of results.