We show that for identical changes in magnetic field, the temperature dependence of the change in isothermal entropy across the martensite-austenite phase transition in different Ni-Mn-In based off-stoichiometric Heusler alloys scales to a single curve. The temperature dependence of magnetoresistance across the same martensite-austenite phase transition in these alloys also scales to follow a similar curve. The temperatures corresponding to the peak value of the isothermal entropy change and the peak magnetoresistance for a particular applied magnetic field are correlated with distinct features observed in the magnetization vs. temperature and resistivity vs. temperature curves respectively of these alloys (in the same magnetic field). These findings can be utilized in estimating the useful temperature regime for the isothermal entropy change and magnetoresistance of Ni-Mn-In based alloys with newer compositions, and to predict the magnitude of these functionalities, without performing actual experiments.

Plasma-immersion ion implantation (PIII) is a potent method to obtain hard and wear-resistant surface on Ti by nitrogen implantation. This presentation is one part of a sequence of experiments to optimize the microstructure and physical properties of TiN through adapting the plasma-processing parameters. In this work, nitrogen ions were implanted into samples of pure Ti at different nitrogen pulse frequency without using any external source of heating. The nitrogen-implanted surfaces were characterized by X-ray diffraction (XRD), Auger electron spectroscopy (AES), optical microscope, nano-indentation technique, ball-on-disk type tribometer, surface profilemeter, Tafel polarization technique for corrosion performance and ellipsometry. The outcomes show that, nitrogen PIII is an effectual method for nitriding titanium and nitrogen pulse frequency affected the microstructure and physical properties of the treated Ti. X-ray diffraction depicted the formation of α-Ti (N) and the cubic TiN after implanting titanium by nitrogen and the thickness of the nitrided layer increased as the nitrogen pulse frequency increased. The wear and corrosion resistance of the nitrogen-implanted titanium are improved and the friction coefficient decreased from nearly 0.8 for the un-implanted titanium to 0.3 for the implanted titanium, this ascribed to the formation of the titanium nitrided phases. Ellipsometric measurements were carried out on the PIII titanium samples at different nitrogen pulse frequency. The ellipsometric measurements show that, the thickness of the nitrided layer and surface roughness increased while the refractive index decreased with increasing nitrogen pulse frequency.

Extensive use of minerals in the world entails the evaluation of major, minor and trace element contents in rocks of different areas. Instrumental neutron activation analysis and calibration free laser induced breakdown spectroscopy were successfully employed to identify and determine the concentration of elements in the rock samples which are collected from the untouched tropical forest area of Ethiopia. Using both techniques 26 minerals are identified and the concentration of each element was estimated and compared to one another. Due to the weak neutron source and the technique limitation, only eight elements of the rock samples were identified by neutron activation analysis. This study provides the baseline value of certain essential minerals in the rocks of studied area and the result shows that the studied area has great potential for mining of Pt and Zn elements. The performances of two analytical methods have been compared. Concentration analysis was done using a Calibration Free-laser induced breakdown spectroscopy algorithm in MATLAB environment.

Photonic crystal (PC) waveguide is one class of PC devices that has been demonstrated for RI measurements. In this paper, we have reported a new design of infiltrated optofluidic sensors based on 2D photonic crystal slab with triangular lattice pattern of ring-shaped holes. The properties of the sensor are simulated using the finite-difference time-domain (FDTD) method. The transmission spectra have been measured by changing the refractive index of holes and it has been found that with increasing refractive index, wavelength position of transmission spectrum shifts. The radius and the shape of the air holes localized at each side of the line defect are optimized to realize high sensitivity, wide measurement range and improved transmission. An improved optofluidic sensor design is also described and a 210 nm wavelength position of upper band edge shift was observed corresponding to a sensitivity of more than 636 nm per refractive index unit (RIU).

In this paper, we investigate the different parameters that affect the distribution of the transmembrane potential of cells brought into contact before electrofusion in a miniaturized fluidic device. In particular, we discuss the deviation of the effective transmembrane voltage compared to the one predicted by Schwan’s law. The application of electric field pulses to biological cells induces a transmembrane potential which leads to cell permeabilization. Electrofusion occurs when several cells are brought into contact while they are electropermeabilized. Nevertheless, we show that in this case, the mutual presence of cells interferes on Schwan’s equation. Consequently, the transmembrane voltage at the cell contacting point is drastically reduced, which is not favorable for an electrofusion in smooth conditions, as the applied voltage needs to be increased to compensate this phenomenon. We show that the introduction of polymer obstacles reverses this trend, as the high electric field region is focused on the fusion zone. To confirm the theory we developed, quantitative biological experiments are presented in which murine melanoma cells were paired and fused in both conditions (with and without obstacles).

Inductively coupled Ar-N2 plasma is characterized by Langmuir probe and optical emission spectroscopy (OES). The plasma parameters including electron temperature, electron number density and electron energy probability functions (EEPFs) are determined by the Langmuir probe for different discharge parameters such as rf power (10–100 W), filling pressure (0.02–0.4 mbar) and argon content (5–95%) in nitrogen discharge. Spectroscopic measurements enable the evaluation of active species concentration ([N],[N2]) in ground electronic state and dissociation fraction. Concentration of active species is increased with the increase in filling pressure in nitrogen discharge keeping argon as an actinometer. It is noticed that the actinometry is an efficient and reliable technique to calculate the concentration of ground electronic state of nitrogen species. Moreover, for different plasma conditions, the molecular dissociation fraction is enhanced, as the Ar content is increased from 5% to 95% in nitrogen discharge. It is found that that dissociation fraction strongly depends on filling pressure and Ar content in nitrogen discharge. Maximum dissociation is observed for 95% Ar at filling pressure of 0.06 mbar. It is also found that the plasma parameters and active species concentration significantly depend on discharge parameters and may be optimized by appropriate selection of discharge conditions.

Since the pioneer work by Bender and Boettcher on non-Hermitian Hamiltonian under paritytime (PT) symmetry [Phys. Rev. Lett. 80, 5243 (1998)], PT-symmetry optical coupled systems have been investigated extensively. Here we propose theoretically perfect transparency of a PT-symmetric acoustic coupled system which is comprised of a waveguide channel and two same-sized side-coupled resonators. Specifically, we demonstrate that with the change in the amplitude of attenuation and amplification coefficient, the spatial symmetry of two resonators is spontaneously broken which triggers an acoustic analog of electromagnetically induced transparency (EIT) by assigning anti-phase to the pressure field inside the two resonators.

In this article, a MEMS-based elastic fluidic actuator is presented. The actuator is driven at its natural frequency. The actuator consists of a thin film of two-phase fluid squeezed between two thin membranes with the top membrane attached to an actuation arm. The top membrane represents the elastic component which deforms under applied pressure. The results show that generated force and displacement amplitude of actuation arm are enhanced for resonant operation. Natural frequency of the actuator is tuned through selection of different actuator components. For current actuator design, maximum generated force and displacement amplitude obtained are approximately 39 mN/W and 16 μm/W, respectively. Natural frequency of the actuator ranges between 110 Hz and over 1000 Hz. This resonant-type actuator is suitable for applications where large generated forces and displacements are needed, such as pumping fluid through micro channels, and providing translational and rotational motion needed in microfluidics systems.

The possibility to do surface measurements on sample containing151Eu by detection of Auger electrons delivered in the decay process of the Mössbauer nucleus is briefly presented herein. The test measurements have been carried out on Eu2O3 powder sample. A higher resonance effect and a lower line width have been obtained in backscattering geometry compared with transmission geometry.

A joint diagnostic system was established for the diagnosis of laser-driven shock wave experiments. The system has high temporal resolution (time resolution ~12 ps) and high spatial resolution (spatial resolution ~7 μm) and fits for diagnostics of the experiment with small sample size and short time physical process. The joint diagnostic system was applied for shock wave measurement on the Shenguang-II laser facility. The passive shock breakout signal and active diagnostic signal were simultaneously obtained. The temporal measurement reliability of the system was verified using a multi-layered target. The experimental results show that the two measurement results were consistent.

The tight focusing of femtosecond radially polarized vortex laser pulse by a high numerical aperture objective is investigated in this paper. Based on Richards-Wolf vectorial diffraction theory, the electric field and the group velocity of the radially polarized vortex femtosecond laser pulse are studied in great detail. It finds that the femtosecond radially polarized vortex laser pulse can travel at various group velocities near the focus, that is, slower or faster than light velocity in vacuum, depending on the numerical aperture of the focusing objective system. Moreover, the effect of spherical aberration of objective, topological charge and time duration of the radially polarized vortex laser pulse on the group velocity distribution near the focus is discussed.

In this paper, we present the molecular density distribution measurement in turbulent nitrogen jet (Re ≈ 3×103), using acetone as molecular tracer. The tracer was seeded in the nitrogen jet by purging through the liquid acetone at ambient temperature. Planar laser sheet of 266 nm wavelength from frequency quadrupled, Q-switched, Nd:YAG laser was used as an excitation source. Emitted fluorescence images of jet flow field were recorded on CMOS camera. The dependence of planar laser induced fluorescence (PLIF) intensity on acetone vapor density was used to convert PLIF image of nitrogen jet into the density image on pixel-by-pixel basis. Instantaneous quantitative density image of nitrogen jet, seeded with acetone, was obtained. The arrowhead-shaped coherent turbulent structures were observed in the present work. It was found that coherent structures were non-overlapping with separate boundaries. Breaking of coherent structures into turbulence was clearly observed above four times jet width.

An accurate experimental and theoretical study has been performed about a phenomenon, not previously reported in the literature, occurring in highly viscous liquids: the formation of a definite pipe structure induced by the passage of a heavy body, this structure lasting for quite a long time. A very rich phenomenology (including mechanical, optical and structural effects) associated with the formation of the pipe has been observed in different liquids. Actually, the peculiar dynamical evolution of that structure does not appear as a trivial manifestation of standard relaxation or spurious effects. In particular, we have revealed different time scales during the evolution of the pipe and a non-monotonous decrease of the persistence time with decreasing viscosity (with the appearance of at least two different maxima). We put forward a microscopic model, consistent with the experimental data, where the pipe behaves as a “dielectric shell” whose time evolution is described through a simple thermodynamical approach, predicting several properties effectively observed.

Irigenin, an isoflavone (mol. formula = C18H16O8), was isolated from the plant Iris hookeriana using dichloromethane as solvent. The compound was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-visible spectroscopy measurements. Structural analysis of XRD data confirmed the orthorhombic structure for the compound. The microstructure of the compound is an aggregate of microcrystals with an irregular morphology. From the UV-visible spectroscopy, the present compound shows indirect allowed transition with an optical band gap (Eg) of around 3.25 eV. The present optical properties of the compound can be utilized in flexible organic electronics applications.