It was demonstrated that by applying highvoltage nanosecond pulses to cells, plasma membrane and cell organelles are permeabilized. New Blumlein configuration that enables a higher repetition rate of variable duration of either bipolar or unipolar highvoltage pulses was designed. A maximal pulse repetition rate of 1.1 MHz was achieved. The new design of pulse generator was built, verified, and tested. The resulting flexibility and variability allow further in vitro experiments to determine the importance of the pulse repetition rate and pulse polarity on membrane permeabilization.
COBISS.SI-ID: 7346772
Detection of nanoparticles in the air is difficult because the particles are so small that they can not be detected by conventional detection methods. The article presents an innovative approach of detection of airborne nanoparticles. It is based on condensation of nanoparticles forming micron sized water droplets which are fed and detected by a capacitive type sensor. The concept is confirmed theoretically and through numerical modelling as well as by experiments.
COBISS.SI-ID: 23475495
Thermal annealing of deposited Ti/Pt layers in the temperature range of 300-700°C was investigated revealing strong impact on the Ti/Pt resistivity. Furthermore, it was determined that temperature coefficient of resistance (TCR) for Ti/Pt temperature sensors and the heater increased with the annealing temperature. Microstructural analysis of deposited and annealed Ti/Pt layers carried out by AES and AFM revealed that recrystallization followed by grain growth process of heat treated Ti/Pt layers started at around 500°C and correlated well with the behavior of electrical properties. Additional insulation steps of assembled microfluidic platform further reduced the power consumption, but also increased the time response of the microfluidic reactor.
COBISS.SI-ID: 8160596
A theoretical model for the optical absorption of amorphous silicon (a-Si) at high electric field aimed for ease of use is developed. Optical absorption is proportional to the number of possible transitions from valence band to conduction band. When an electron is excited by a photon, the atom it was bound to is ionized and bends all the energy levels to form a Coulombic potential funnel. A high electric field tilts all the energy levels. The Coulombic funnel and the tilted conduction band form a potential barrier through which an electron can tunnel, giving rise to additional available density of conduction band states, thus increasing the optical absorption.
COBISS.SI-ID: 8864596
This article reports a novel strip-type micro-throttle pump with a rectangular actuator geometry, with more efficient chip surface consumption compared to existing micro-pumps with circular actuators. Due to the complex structure and operation of the proposed device, determination of detailed structural parameters is essential. Therefore, we developed an advanced, fully coupled 3D electro-fluid-solid mechanics simulation model in COMSOL that includes fluid inertial effects and a hyper-elastic model for PDMS and no-slip boundary condition in fluid-wall interface. Numerical simulations resulted in accurate virtual prototyping of the proposed device, detailed operation analysis and optimization of crucial geometrical parameters.
COBISS.SI-ID: 9729620