A setup to measure the temperature-dependent heating power of magnetically heated nanoparticles up to high temperature.

Magnetic heating, namely, the use of heat released by magnetic nanoparticles (MNPs) excited with a high-frequency magnetic field, has so far been mainly used for biological applications. More recently, it has been shown that this heat can be used to catalyze chemical reactions, some of them occurring at temperatures up to 700 °C. The full exploitation of MNP heating properties requires the knowledge of the temperature dependence of their heating power up to high temperatures. Here, a setup to perform such measurements is described based on the use of a pyrometer for high-temperature measurements and on a protocol based on the acquisition of cooling curves, which allows us to take into account calorimeter losses. We demonstrate that the setup permits to perform measurements under a controlled atmosphere on solid state samples up to 550 °C. It should in principle be able to perform measurements up to 900 °C. The method, uncertainties, and possible artifacts are described and analyzed in detail. The influence on losses of putting under vacuum different parts of the calorimeter is measured. To illustrate the setup possibilities, the temperature dependence of heating power is measured on four samples displaying very different behaviors. Their heating power increases or decreases with temperature, displaying temperature sensibilities ranging from -2.5 to +4.4% K-1. This setup is useful to characterize the MNPs for magnetically heated catalysis applications and to produce data that will be used to test models permitting to predict the temperature dependence of MNP heating power.

[Cytomorphologic criteria of bronchioloalveolar cell cancer]. / Zytomorphologische Kriterien des Bronchioloalveolarzellkarzinoms.

Cytological material obtained from 100 patients with histologically proven bronchiolo-alveolar cell carcinoma was evaluated on the basis of 27 criteria. Particular features observed were a monocytoid nuclear delimitation (98.4%), central position of the nucleus (90.2%), light-coloured nuclear sap (52.5%), double-nucleation (98.4%), multinucleation (72.1%), phagocytosis (55.7%). Of the features of the accompanying reaction, psuedoproteinosis (9.8%), the presence of hyperplastic pneumocytes II (75.4%) and psammoma bodies (1.6%) are worthy of mention.