This article provides an extensive outlook of different types of piezoelectric actuated micro-pumps published in the literature recently. We start by reminding the reader about the conventional operating parameters used to quantify the capabilities of these devices. After this introductory stage, we describe and classify the most prominent micro-pump's geometries found with piezoelectric actuation. At this point we identify the parameters given previously for each pump in order to establish a subsequent discussion in which the trends of different families are compared. Specific attention is given to the particularities of each case namely: flow rates and backpressures.

Hybrid organic-inorganic heterostructures have been produced using the conducting polymer PEDOT:PSS and three types of semiconductor single crystals, i.e., high-ohmic and low-ohmic cadmium sulphide (CdS, n-type semiconductor) and low-ohmic cadmium telluride (CdTe, p-type semiconductor). A photovoltaic (PV) response was observed upon light illumination of both CdS/PEDOT:PSS and CdTe/PEDOT:PSS heterojunctions. Photocurrent spectra unequivocally evidenced the main contribution of band-band transitions of inorganic crystals to the PV response, and current-voltage measurements indicated that band bending due to a depleting region at the surface of the crystals takes place. The suggested band bending was consistent with the model of the vacuum level alignment only at the interface of the low-ohmic CdS crystal and the polymer, which results in formation of a Schottky barrier responsible for the PV response. However, the analogous band bending for high-ohmic CdS and p-type CdTe crystals could be associated only with the Fermi level pinning regime at the semiconductor interfaces.

The stability, structural, elastic, electronic and optical properties of perovskite hydrides BaLiH3 and SrLiH3 were investigated by the density functional theory. The calculated lattice parameters are in well agreement with previous calculation and experimental data. The energy band structure, density of states, born effective charge and Mulliken charge population were obtained. BaLiH3 and SrLiH3 present an indirect band gap of 2.23 eV and 1.86 eV at equilibrium. The top of the valence band reflects the s electronic character for both structures. Furthermore, the absorption spectrum, refractive index, extinction coefficient, reflectivity, energy-loss spectrum and dielectric function were calculated. The origin of the spectral peaks was interpreted based on the electronic structure. The static dielectric constant and static refractive index are proportional to the fundamental indirect band gap.

GaAs nanocrystallites are elaborated by electrochemical etching of n+ type GaAs substrates. Photoluminescence (PL) and atomic force microscope (AFM) images analysis are used to study the porous layers obtained with different etching times. Two kind of quantum confinement due to the formation of two nanostructures of different sizes are observed from room temperature photoluminescence (RTPL) spectra. The surface topography and the density of grains of the porous GaAs (π-GaAs) samples are investigated using the AFM technique. AFM images showed that the structure of films was nanocrystalline with a grain size close to 7 nm, this was confirmed by photoluminescence spectroscopy (PL) and the effective mass theory.

This work presents the use of molecular dynamics (MD) and the code of Dl_Poly, in order to study the structure of fluoride glass after melting and quenching. We are realized the processing phase liquid-phase, simulating rapid quenching at different speeds to see the effect of quenching rate on the operation of the devitrification. This technique of simulation has become a powerful tool for investigating the microscopic behaviour of matter as well as for calculating macroscopic observable quantities. As basic results, we calculated the interatomic distance, angles and statistics, which help us to know the geometric form and the structure of PbF2. These results are in experimental agreement to those reported in literature.

Here, large-scale ordered periodic silicon pillar arrays were prepared using nanosphere lithography. And, the diameter and the density of nanopillar arrays are determined by the initial diameter of polystyrene (PS) spheres. In our experiment, the nanopillar has a diameter of approximately 50 nm, and the density of silicon pillar is 6×109/cm2. This array shows a field emission property with a low turn-on field of 9.8 V μm-1 at a current density of 10 μA cm-2. And the field enhancement factor is about 560. The Fowler-Nordheim plot obtained is linearly dependent, indicating that the emission current arises from the F-N tunnelling effect.

The temperature distribution in dentin under pulse Er:YAG laser radiation has been studied and simulated, analytically. For this reason we considered heat deposited in dentin due to laser radiation. The heat conduction equation has been solved and the temperature distribution has been obtained. The obtained results then have been used for dentin and discussed. Based on the simulation, the temperature rise to 40.5 K for 300 mJ and 21 pulses which have very good consistency with the experiment.

A widely tunable injection seeded Ti:sapphire ring cavity has been developed and characterized. The seeding source is a single mode quasi continuous wave Ti:Sa laser, continually tunable over more than 2.5 cm-1 (75 GHz). Its short term (pulse to pulse) stability is on the order of ±3.2 MHz at a repetition rate of 20 Hz. The long term absolute stability is limited up to now to about ±10 MHz. These frequency characteristics are transferred to the pulsed emission with minor degradations. The frequency chirps and shifts during the pulses are also studied using an optical heterodyne technique.

Analysis of tunable photonic microwave bandpass filter with negative coefficient based on an electro-optic phase modulator (EOPM) followed by a fiber Michelson interferometer with orthogonally polarized arms is presented. The Michelson interferometer is made by connecting two fibers to the output ports of a polarization beamsplitter (PBS) and attaching high reflecting Bragg gratings at the other end of the fibers. The negative coefficient is generated from the optical interference of the two phase modulated optical carriers when recombined at the PBS. A two-tap microwave bandpass filter with one negative coefficient is presented. The chromatic dispersion is expected to have no effect on this filter. The filter is tunable over a wide frequency bandwidth using short fiber lengths.

The loss calculation in soft magnetic materials, used in the manufacturing industry, is still ruled by Steinmetz's simple law. It has remained unchallenged for more than a century, unproven but successfully used by designers of magnetic components. Based on experiments carried out on soft NO Fe–Si and Mn–Zn ferrite samples, in this paper we present a model of Steinmetz's approximation, based on the hyperbolic model. We also make suggestions for the formula's possible extension to a wider range of coercivity, possibly covering not only soft iron but also other groups of magnetic materials as well, used in industry.

Solid state nuclear track detectors (SSNTDs), such as CR-39, have been used to detect energetic charged particles and neutrons. Of the neutron and charged particle interactions that can occur in CR-39, the one that is the most easily identifiable is the carbon breakup reaction. The observation of a triple track, which appears as three alpha particle tracks breaking away from a center point, is diagnostic of the 12C(n, n’)3α carbon breakup reaction. Such triple tracks have been observed in CR-39 detectors that have been used in Pd/D co-deposition experiments. In this communication, triple tracks in CR-39 detectors observed in Pd/D co-deposition experiments are compared with those generated upon exposure to a DT neutron source. It was found that both sets of tracks were indistinguishable. Both symmetric and asymmetric tracks were observed. Using linear energy transfer (LET) curves and track modeling, the energy of the neutron that created the triple track can be estimated.

Dye-coated single microspheres exhibit whispering gallery modes (WGMs) within the spontaneous emission bandwidth of the dye spectrum. These modes are extremely sensitive to the size, shape and the refractive index besides their coating thickness. Aden and Kerker theory has been used to simulate the WGMs. The effect of refractive index of the medium and the microsphere on WGMs has been studied. Variations are observed in the decay rates of the excited state with the size of the microspheres on varying the refractive index of the medium surrounding the microcavity. It is found that (i) the observed quality factors (Q-values) are smaller by several orders of magnitude than those expected theoretically and (ii) the radiative rates are enhanced for Q-values > 3 × 103.

Contact potential difference (CPD) was measured by macroscopic Kelvin probe instrument and scanning Kelvin probe microscope on Al, Ni and Pt on ITO substrates at ambient conditions. CPD values measured by scanning Kelvin probe microscope and macroscopic Kelvin probe are close within the error of about 10–30% for large studied objects, whereas scanning Kelvin probe microscope signal decreases, when the object size becomes smaller than 1.4 μm. CPD and electric field signals measured using many-pass technique allowed us to estimate the influence of electrostatic field disturbance, especially, in the case of small objects.

Outlined here is a technique for sub-wavelength infrared surface imaging performed using a phase matched optical parametric oscillator laser and an atomic force microscope as the detection mechanism. The technique uses a novel surface excitation illumination approach to perform simultaneously chemical mapping and AFM topography imaging with an image resolution of 200 nm. This method was demonstrated by imaging polystyrene micro-structures.

The Raman and FT-IR spectra of 3,5-dimethoxybenzyl alcohol (L1OH) were measured experimentally, and density functional theory (DFT) method were used to calculate the equilibrium geometry and vibration frequencies of L1OH for the first time. The results showed that the calculated frequencies agree well with the experimental ones. Potential energy distribution of each frequency was worked out by normal mode analysis. Thereafter a detail assignment of the vibrational frequencies of L1OH has been obtained.