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Patterning processes in amorphous Se and $$\hbox {As}_{20}\hbox {Se}_{80}$$ films at short electron beam pulses (from 200 ns to 100 ms) were studied for the first time. The surface reliefs occurring as after-pulses effects were recorded and analysed. Giant hillock formation was detected at about $$200\,\upmu \hbox {s}$$ pulses while very small changes in surface morphology were observed at other pulse durations. The obtained data indicate that the strong increase in e-beam sensitivity of mechanical response (giant surface hillock formation) at about $$200\,\upmu \hbox {s}$$ is due to some resonance effect. A qualitative description is given, relating these times to the characteristic generation and relaxation time of the defects in these materials, which illuminates the process of e-beam induced structural rearrangement. The measurement has been performed at room temperature and at $$-120\,^{\circ }\hbox {C}$$ and only a 20% change in the maximal pattern height has been detected. [ABSTRACT FROM AUTHOR]

For pathogens identification, the PCR test is a widely used method, which requires the isolation of nucleic acids from different samples. This extraction can be based on the principle of magnetic separation. In our work, amine-functionalized magnesium ferrite nanoparticles were synthesized for this application by the coprecipitation of ethanolamine in ethylene glycol from Mg(II) and Fe(II) precursors. The conventional synthesis method involves a reaction time of 12 h (MgFe 2 O 4 -H&R MNP); however, in our modified method, the reaction time could be significantly reduced to only 4 min by microwave-assisted synthesis (MgFe 2 O 4 -MW MNP). A comparison was made between the amine-functionalized MgFe 2 O 4 samples prepared by two methods in terms of the DNA-binding capacity. The experimental results showed that the two types of amine-functionalized magnesium ferrite magnetic nanoparticles (MNPs) were equally effective in terms of their DNA extraction yield. Moreover, by using a few minutes-long microwave synthesis, we obtained the same quality magnesium ferrite particles as those made through the long and energy-intensive 12-h production method. This advancement has the potential to improve and expedite pathogen identification processes, helping to better prevent the spread of epidemics.

Easy preparation, good yield and easy recovery are the key challenges in the development of industrial catalysts. To meet all these three criteria, we have prepared intelligent, magnetizable NiFe 2 O 4 - and CoFe 2 O 4 -supported palladium catalysts that can be easily and completely recovered from the reaction medium by magnetic separation. The fast and facile preparation was achieved by a solvothermal method followed by sonochemical-assisted decomposition of the palladium nanoparticles onto the surface of the magnetic nanoparticles. The metal-support interaction was enhanced by amine functionalization of the supports using monoethanolamine. The performance and stability of the non-functionalized and amine-functionalized NiFe 2 O 4 - and CoFe 2 O 4 -supported palladium catalysts were compared in the industrially important nitrobenzene hydrogenation reaction. All catalysts showed high catalytic activity during aniline synthesis; complete nitrobenzene conversion and high aniline yield (above 97 n/n%) and selectivity (above 98 n/n%) were achieved. However, during reuse tests, the activity of the non-functionalized catalysts decreased, as the palladium was leached from the surface of the support. On the other hand, in the case of their amine-functionalized counterparts, there was no decrease in activity, and a non-significant decrease in palladium content could be measured. Based on these results, it can be concluded that amine functionalization of transition metal ferrites may result in more effective catalysts due to the enhanced metal-carrier interaction between the support and the precious metal.

The aim of this study was to develop an in vitro model in which the pressure in the periapical tissues can be measured during loading. Extracted human maxillary central incisors were embedded into resin blocks that had physical characteristics similar to bone and periodontal ligament. Each tooth was loaded with 20, 40, 50, 60, 75, 85, 100, 200, 300 and 450 N vertical forces from the incisal edge of the crown; this procedure was carried out three consecutive times. A minute resistor embedded in the periapical space was used to detect apical pressure changes during occlusal loading. The ratio of apical pressure changes (delta P) to the loading force changes (delta F) was calculated. The periapical pressure detected was in direct proportion to the loading force. The mean value of delta P/delta F was 5.994 kPa/N (SD = 2.04). Direct proportionality was found between the coronal loading and the apical hydrostatic pressure. The (delta P)/(delta F) ratio determined in this study makes it easier to estimate the apical hydrostatic pressure values during occlusal loading of single rooted teeth. In this study the apical pressure generated under occlusal loading was of the same magnitude as that estimated with the finite element method.