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Highlights: [•] A capacitive novel sensor for measurement of a rotating shaft angular speed was introduced. [•] A mathematical model for modeling of the sensor was given. [•] The effects of the sensor’s design parameters on its stability and sensibility were investigated. [ABSTRACT FROM AUTHOR]

An analytical study using Variational Iteration Method (VIM) is carried out in order to investigate the vibrations of electro-statically actuated double-clamped and simply-supported microbeams. Effects of applied voltage and residual axial load on the nonlinear natural frequency and deflection of the microbeams are studied. It shows that pre-compression in microbeams increases the amplitude of deflections for a specific applied voltage. Also, an increase in pre-tension motivates the microbeam to show more nonlinear behavior in an applied voltage. Predicted results are compared with the experimental data available in the literature and also with numerical results which shows a good agreement. It is concluded that the second order approximation of the VIM leads to highly accurate solutions which are valid for a wide range of vibration amplitudes. [ABSTRACT FROM AUTHOR]

The concentration and distribution of fluorine in mature leaves of Camellia sinensis were determined using micro-PIGE. The elemental concentration was measured as 2210 ± 450 ppm. Fluorine showed clear localization in the epidermis. Fluorine was distributed uniformly in the upper epidermis, suggesting that fluorine was localized in the cytoplasm. On the other hand, extremely concentrated areas of fluorine were observed in the lower epidermis. [ABSTRACT FROM AUTHOR]

In this paper, we measured the concentrations and spatial distributions of aluminum and manganese with the growing period of a tea leaf. Both elemental concentrations increased with the growing period and showed a rapid increase between five and six months. Aluminum showed clear localization in the epidermis with the growing period. Manganese did not show clear localization like aluminum throughout the growing period. The spatial correlation between aluminum and manganese were not observed. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the geometric analysis of the electric field edge effect in three charged rectangular conductors. This effect is taken into account for evaluating the electric capacitance and the force between charged bodies. The comprehensive model presented in this work includes seven geometric parameters to fully define the system and calculate a correction factor to the analytical model. The correction factor is presented as closed-form equations. Instead of using finite element models, these equations can be used for determining the gradient of capacitance and the electrostatic force between charged bodies. [Copyright &y& Elsevier]

A new treatment planning system (TPS) was designed and developed for a new treatment system, which consisted of a micro-beam-enabled linac with robotics and a real-time tracking system. We also evaluated the effectiveness of the implemented algorithms of optimization and dose calculations in the TPS for the new treatment system. In the TPS, the optimization procedure consisted of the pseudo Beam's-Eye-View method for finding the optimized beam directions and the steepest-descent method for determination of beam intensities. We used the superposition-/convolution-based (SC-based) algorithm and Monte Carlo-based (MC-based) algorithm to calculate dose distributions using CT image data sets. In the SC-based algorithm, dose density scaling was applied for the calculation of inhomogeneous corrections. The MC-based algorithm was implemented with Geant4 toolkit and a phase-based approach using a network-parallel computing. From the evaluation of the TPS, the system can optimize the direction and intensity of individual beams. The accuracy of the dose calculated by the SC-based algorithm was less than 1 % on average with the calculation time of 15 s for one beam. However, the MC-based algorithm needed 72 min for one beam using the phase-based approach, even though the MC-based algorithm with the parallel computing could decrease multiple beam calculations and had 18.4 times faster calculation speed using the parallel computing. The SC-based algorithm could be practically acceptable for the dose calculation in terms of the accuracy and computation time. Additionally, we have found a dosimetric advantage of proton Bragg peak-like dose distribution in micro-beam treatment. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a curved beam model for the nonlinear electro-dynamic analysis of micro-beams with initial curvature, taking into account the nonlinear electric force and nonlinear deformation. The governing equations of motion and boundary conditions are derived in an arc coordinate system. Unlike previous studies based on von Karman nonlinearity or considering mid-plane stretching only, the present study does not involve any assumptions on nonlinear deformation. Differential quadrature method and Petzold–Gear BDF method are employed to obtain the nonlinear electro-dynamic behavior of curved micro-beams. The effects of nonlinear deformation, initial gap and initial rise on the nonlinear electro-dynamic characteristics are studied. [Copyright &y& Elsevier]

Abstract: This paper deals with investigation into the stability analysis for transverse motions of a cantilever micro-beam, which is axially loaded due to a voltage applied to the piezoelectric layers located on the lower and upper surfaces of the micro-beam. The piezoelectric layers are pinned to the open end of the micro-beam and not bonded to it through its length. Application of the DC and AC piezoelectric actuations creates steady and time varying axial forces. The equation of the motion is derived using variational principal, and discretized using modal expansion theorem. The differential equations of the discretized model are a set of Mathieu type ODEs, whose stability analysis is performed using Floquet theory for multiple degree of freedom systems. Considering first two eigen-functions in the modal expansion theorem leads in the prediction of flutter type of instability as a consequence of Hopf bifurcation, which is not seen in the reduced single degree of freedom system. The object of the present study is to passively control the flutter instability in the proposed model by applying AC voltage with suitable amplitude and frequency to the piezoelectric layers. The effect of various parameters on the stability of the structure, including damping coefficient, amplitude of the DC and AC voltages, and the frequency of the applied AC voltage is studied. [Copyright &y& Elsevier]

Abstract: This paper presents an analytical study on the forced vibration of micro-switches under combined electrostaticc, intermolecular forces and axial residual stress. The micro-switch considered in this study is made of non-homogeneous functionally graded material with two material phases. The nonlinear partial differential equation which describes the forced vvibration of the micro-beam is derived based on the framework of von Karman-type geometric nonlinearity and Euler-Bernoulli beam theory, aand are solved using the method of averaging. The modulations of the amplitude of clamped-clamped micro-switch are obtained. TThe present results are validated through direct comparisons with published experimental results. Excellent agreement has been achieved. A parametric study is conducted to show the effects of material composition and AC harmonic force on the frequency response characteristics of the micro-switch. [Copyright &y& Elsevier]

Abstract: In the present article an investigation is presented into the stability of an electro-statically deflected clamped–clamped micro-beam sandwiched by two piezoelectric layers undergoing a parametric excitation applying an AC voltage to these layers. Applying an electrostatic actuation not only deflects the micro-beam but also decreases the bending stiffness of the structure, which can lead the structure to an unstable position by undergoing a saddle node bifurcation. Utilizing an appropriate AC actuation voltage to the piezoelectric layers produces a time varying axial force, which can play the role of a stabilizer exciting the system parameter. The governing equation of the motion is a nonlinear electro-mechanically coupled type PDE, which is derived using variational principle and discretized, applying Eigen-function expansion method. The resultant is a Mathieu type equation in its damped form. Using Floquet theory for single degree of freedom system the stable and unstable regions of the problem are investigated. The effects of viscous damping and electrostatic actuation on the stable regions of the problem are also studied. [Copyright &y& Elsevier]

Abstract: A micro-beam NRA system by means of a resonant nuclear reaction of 1H(15N, αγ)12C has been developed at the beam line in MALT, University of Tokyo. The beam optics was analyzed in terms of the phase diagram. By carefully suppressing the spherical aberration of the final quadrupole magnetic lens, the 15N beam at the energy of 6.4MeV was focused on targets with a size of 17μm×30μm. For the precise positioning of the sample and beam spot, a combination of the mirror and optical microscope was adopted, so that the hydrogen concentration can be measured at a desirable position of the sample. With this new system, the hydrogen concentrations of fatigue-fractured surfaces of glassy alloys were determined from the viewpoint of the hydrogen embrittlement: Zr50Cu37Al10Pd3 and Zr50Cu40Al10. Depth-resolved two-dimensional (2D) mapping of hydrogen concentration was performed in the area of 3mm×3mm with an in-plane resolution of 150μm. The maps taken at three different depths revealed that the hydrogen concentration is higher in the fatigue-fractured regions in both samples. [Copyright &y& Elsevier]

Abstract: Nuclear reaction analyses (NRA) based on the 3He(2H,4He)1H reaction were previously performed to follow the evolution of implanted 3He in polycrystalline UO2 samples. Experimental results pointed to an enhancement above 800°C of the diffusion coefficient of helium over several microns in the vicinity of the grain boundaries, with respect to the diffusion coefficient within the grain. This was ascribed to the fact that grain boundaries are probably defect sinks which locally modify the defect concentrations. This study aims at demonstrating the particular effect of grain boundaries on helium migration. To this end, 3He implanted polycrystalline UO2 samples were cracked then annealed at 900°C. Helium migration in the vicinity of the grain boundaries and near the crack was investigated by means of NRA microanalyses. Helium depletion extends over far larger distances in the vicinity of the grain boundaries than near the crack. Experimental evidence has been collected of the particular effect of grain boundaries on helium migration, which do not act as free surfaces at which helium atoms are simply released. [Copyright &y& Elsevier]

Abstract: Probes made of carbon fibre composite NB41 were exposed to deuterium plasmas in the TEXTOR tokamak and in a simulator of plasma–wall interactions, PISCES. The aim was to assess the deuterium retention and its lateral and depth distribution. The analysis was performed by means of D(3He, p)4He and 12C(3He, p)14N nuclear reactions analysis using a standard (1mm spot) and micro-beam (20μm resolution). The measurements have revealed non uniform distribution of deuterium atoms in micro-regions: differences by a factor of 3 between the maximum and minimum deuterium concentrations. The differences were associated with the orientation and type of fibres for samples exposed in PICSES. For surface structure in the erosion zone of samples exposed to a tokamak plasma the micro-regions were more complex. Depth profiling has indicated migration of fuel into the bulk of materials. [Copyright &y& Elsevier]

Abstract: Cross sections of deposited layers in the Joint European Torus (JET) were analysed using the nuclear micro analysis at the Tandem Laboratory, Uppsala University. For deuterium and beryllium the nuclear reactions 2D(3He,p)4He and 9Be(3He,p n )11B were exploited for analysis. Typically the analyses have been made with 10μm spatial resolution and a sensitivity of better than one atomic percent for beryllium or deuterium in carbon matrix. Comparing several different surface treatment techniques shows that polishing the sample surface give very good optical surface information but that some amount of deuterium and beryllium probably is removed. For good quantitative results the measurement can either be done on a rough surface or the top of the polished surface can be cut off. [Copyright &y& Elsevier]

Abstract: The energy-dispersive X-ray fluorescence spectrometer for analysis of conventional and micro-samples using pinhole collimators of various sizes is developed. The measurements can be performed in the air or, in order to decrease the absorption of long-wavelength radiation of low-Z elements, in helium atmosphere. The sample is excited by the air-cooled Rh target X-ray tube of ca. 100 μm nominal focal spot size and maximum power 75 W. The X-ray spectra of the samples are collected by thermoelectrically cooled Si-PIN detector. The tungsten pinhole collimators of the size holes from 50 to 2000 μm are placed between primary filter and analyzed sample to reduce size of analyzed area. The sample can be moved using the X–Y stage. The position of the sample is monitored by CCD camera and two laser pointers. The beam spot sizes for various collimators are evaluated by the thin-wire and knife-edge methods. Beside the beam spot sizes, the loss of radiation intensity and the changes of spectral distribution of the incident radiation caused by applying various collimators are also investigated. The sample-surface-down geometry in the designed spectrometer allows for a simple analysis of various samples: solutions, loose powders, solid samples of conventional size and micro-samples. [Copyright &y& Elsevier]

Abstract: In order to increase accessibility to the μSR spectroscopy for people in various fields of science and engineering, a conceptual design study was made to realize a compact and inexpensive muon source by using 300MeV electron microtron and a large-acceptance muon-capture. Advanced radiography imaging with muon spin probes will become possible for bio-medical studies, inspection of re-enforced architectures, etc. [Copyright &y& Elsevier]

Abstract: Multiply charged ion beam transmission through insulating capillaries is today a very active field of research. Thanks to the work of several groups during the last five years, several features of this unexpected process have been evidenced. The open challenge is to understand and control the self-organized charging-up of the capillary walls, which leads finally to the ion transmission. Up to now, the specific charge distribution on the inner surface, as well as the dynamics of the build-up, are still to be understood. While capillaries usually studied are microscopic pore networks etched in different materials, our concern is in macroscopic single capillaries made of glass. With a length of several centimeters and a diameter of a few micrometers at the exit, these capillaries have nevertheless the same aspect ratio as the etched pores (length/diameter≈100). One of the leading goals of this research on single capillaries is to produce multi-charged ion beams with diameters smaller than a micrometer (nano-beams). These glass capillaries offer the opportunity to be used as an ion funnel due to their amazing properties of guiding and focusing highly charged ion beams without altering neither their initial charge state nor the beam emittance (<10−3 πmmmrad). However, the understanding of the underlying process is not complete and relies on models assuming charge patches distributed along the capillary and which still need to be tested. We present the first observation imaging the dynamics of the charging-up process in single glass capillaries. During the build-up of the self-organized charge deposition on the capillary walls, the 230keV Xe23+ transmitted beam is deflected back and forth several times as the outgoing current increases. This is in agreement with the picture of charge patches created sequentially along the capillary and thus deflecting the beam until a stationary state is reached. [Copyright &y& Elsevier]

Nonlinear vibration of a fractional viscoelastic micro-beam is investigated in this paper. The Euler–Bernoulli beam theory and the nonlinear von Kármán strain are used to model the beam. The small-scale effects are considered by employing the Modified Couple Stress Theory (MCST). The viscoelastic material of the beam is modeled via the fractional Kelvin–Voigt model. Utilizing the Hamilton's Principle, a partial fractional differential equation is derived as the governing equation of motion. The Finite Difference Method (FDM) and the Galerkin method are used together for solving the partial fractional differential equation. The FDM is utilized to discretize the time domain, and the Galerkin method is employed to discretize the space domain. In this paper, the FDM and the Shooting method are coupled together to find the periodic solution of the fractional micro-beam and draw the corresponding amplitude–frequency curve. The effects of the order of the fractional derivative, viscoelastic model, and the micro-scale are studied numerically here in this study. Numerical simulations suggest that, the effect of the fractional derivative is very strong and must be considered for modeling the viscoelastic behavior; especially when the amplitude is high. Results also show that the effects of the nonlinear viscoelastic part are considerable when the amplitude is high; this may happen when the excitation frequency is near the natural frequency, at which the maximum amplitude occurs. • The viscoelastic material of the micro-beam is modeled via the fractional Kelvin–Voigt model. • The FDM and the Shooting method are coupled together to find the periodic solution of the fractional micro-beam. • The effects of the fractional viscoelastic model and fractional-order on the resonance are investigated. • Results show that the effects of the fractional model are considerable when the amplitude is high. [ABSTRACT FROM AUTHOR]

Abstract: A micro-beam NRA system, by means of a resonant nuclear reaction 1H(15N, αγ)12C, has been developed for the purpose of the 3D mapping of the hydrogen distribution in solids. To obtain the tens μm size of the beam spot, the combination of the newly proposed tapered glass capillary and a conventional quadrupole magnetic lens is employed. An Y patterned film on a substrate is prepared as an application of the developed system. The 6MeV 15N beam focused by glass capillaries down to 50μm successfully shows the hydrogen distribution. The in-plane NRA profile implies that the beam emitted from the glass capillary outlet is parallel, although the original beam has a considerable divergence. The NRA measurements in the 103 Pa N2 atmosphere due to the low gas conductance of the glass capillary is also demonstrated. [Copyright &y& Elsevier]

A new method for measuring the mechanical properties of SiC coatings on spherical particles was developed. The method allows the evaluation of the mechanical properties of the SiC coating along different orientations. The elastic modulus determined using three-point bending is in agreement with that obtained from nanoindentation. Using a pre-cracked micro-cantilever, the fracture toughness was found to be anisotropic, with a value of 3.47MPam−1 along the tangential direction and a value of 6.72MPam−1 along the radial direction. [Copyright &y& Elsevier]

Abstract: A XVIII century polychrome porcelain, of complex layered structure has been analysed by using several techniques. The studied porcelain shard was a fragment of a flooring tile from the “Casita del Labrador”, a small palace located in Aranjuez, near Madrid. The high spatial resolution of the α-PIXE technique, an appropriate choice of the beam energies and the use of an external micro-beam have allowed to determine the composition of the constituent layers almost free from interferences, which was not possible with other analytical techniques. The nature of the pigments in particular is now well understood. PIXE analysis was confirmed by traditional, although destructive, XRD, XRF and SEM-EDS analyses. [Copyright &y& Elsevier]

Abstract: Over the last two decades neutron micro-beam has increasingly been developing in view of various applications in molecular activation analysis, micro-radiography in space and aviation and in radiation induced bystander effects in bio-cells. In this paper the structure and simulation of a neutron micro-beam is presented. The collimator for micro-beam is made of a polyethylene cylinder with a small hole along the centerline of the cylinder. The hole is filled with very thin needles in triangular or rectangular arrangement. The neutron source was reactor neutrons or a spontaneous Cf-252 neutron source falling on the top side of the collimator. The outgoing thermal and epithermal neutron fluxes were calculated. [Copyright &y& Elsevier]

Abstract: Ion implantation-induced damage depth profiles of 450keV Al+ ion-implanted 6H-SiC were studied using RBS/C technique for implantations along channeling direction and non-channeling direction with fluence of 3.4×1015 cm−2. Bevelling method of sample preparation was used to get access to the deeper situated layers over the whole damaged region and below. To determine damage degree at the specific depth of the bevelled sample, RBS/C technique combined with a 3MeV Li2+ ion beam of size of about 30μm×30μm was utilized (micro-RBS/C). The micro-RBS/C method combined with the bevelling technique gave us a possibility to probe deeper reaching damage regions than in the case of conventional RBS/C investigations. It also utilizes a near-surface part of backscattered spectra, which is slightly influenced by damage created by probing ions and a random fraction of probing beam. Additionally, there is no need to perform energy calibration of detector for backscattered particles. Due to much smaller sample area hit by probing ions of micro-beam, the required fluence, comparable to that at conventional RBS/C measurements is obtained at much lower charge. Negligibly small effect of bevelling-induced mechanical damage has been observed in this study. The obtained results by micro-RBS/C method validate the results of computer simulations (Crystal-TRIM software). [Copyright &y& Elsevier]

Abstract: A two-dimensional analysis of helium in UO2 sintered disks has been achieved on a micrometric scale by using the NRA technique and upgrading the detection arrangement. The transmission mode detection procedures, localization of the region scanned and normalization of the helium lateral distributions are now well established. For sintered UO2 pellets implanted at a dose of 2×1016 3He/cm2, the results show that the lateral helium distribution is correlated to the sample microstructure after annealing for 1h at 1300°C. The enhanced desorption of helium in the vicinity of grain boundaries points to them playing an essential part in helium diffusion in UO2. [Copyright &y& Elsevier]

Abstract: X-ray tube based, micro-beam X-ray fluorescence scanning spectrometer has been equipped with two energy dispersive X-ray detectors. The two-detector configuration allows for simultaneous collection of X-ray fluorescence (XRF) and transmitted X-ray beam signals with a spatial resolution in the range of 10–50μm, depending on the X-ray focussing element in use. The XRF signal is collected with a standard, liquid nitrogen cooled Si(Li) detector. The X-ray beam transmitted through the sample is acquired with a thermoelectrically cooled, silicon drift (SD) detector. The data acquisition is carried out in a fully automatic way under control of the SPECTOR-LOCATOR software. The software controls the scanning procedure and X-ray spectra acquisition during the scan. The energy dispersive X-ray spectra collected at every “pixel” are stored for off-line processing. For selected regions of interest (ROI’s), the element maps are constructed and displayed on-line. The spectrometer has been used for mapping elemental distributions and for performing 2D- and 3D-tomograpic imaging of minute objects in X-ray absorption and in X-ray fluorescence mode. A unique feature of the described system is simultaneous utilization of the two detectors, Si(Li) and SD, which adds new options for quantitative analysis and data interpretation. Examples of elemental mapping and 3D tomographic imaging as well as the advanced features of the SPECTOR-LOCATOR measurement control and data acquisition software are presented in this work. [Copyright &y& Elsevier]

Incrusted pottery samples from the territory of Hungary were analyzed by micro-PIXE technique. Measurements were executed on the front and back side of the samples and inside the incrustations too. We succeeded to group the pottery from different regions and periods by the composition of the ornament. It was concluded that the elemental composition of the ornament may be characteristic to the provenance of the pottery.In case of samples from Vo¨rs-Ma´riaasszonysziget the presence of a kind of grit in the incrustations with high calcium and phosphorus content was established. The material of the grit is presumably bone. Samples from other archaeological localities can be described by incrustations with different compositions. Incrustations in the samples from Balatonfu¨zo¨ are presumably composed of limestone (CaCO3), from Baradla cave (Aggtelek) probably of white clay paste (kaolinite).It was also concluded that the red color of the ornaments of some sample from Baradla cave is caused by hematite. [Copyright &y& Elsevier]

We have developed two techniques for microscopic ion beam imaging and profiling, both based on scintillators, particularly suitable for applications in deep lithography with protons (DLP) or with heavier ions. The first one employs a scintillating fiberoptic plate and a CCD camera with suitable lenses, the second makes use of a small scintillator optically coupled to a compact photomultiplier. We have proved the possibility of spanning from single beam particles counting up to several nA currents. Both the devices are successfully exploited for on-line control of proton beams, down to a beam size of less than 50 μm, in the framework of DLP application. [Copyright &y& Elsevier]

A micro-beam of hard X-ray (10 keV) as small as 5 μm in diameter has been generated using a single refractive lens (SRL) and been applied for direct writing, which may find possible applications in three-dimensional (3D) micro-fabrication. The refractive lenses are parabolic-shaped concave lenses with a radius of 4 μm and an aperture of 179 μm and have been produced using our high aspect-ratio techniques with synchrotron radiation (SR). [Copyright &y& Elsevier]

We have used a micrometer size X-ray beam generated from a synchrotron light source to measure the map of sensitivity in polycrystalline diamond films. Devices probed consist of sandwich structures in order to maintain the electric field uniform in the device. This study focuses on high-grade (detector) commercially available CVD material, with high charge transport properties and big grain size. As the X-ray beam is scanned over the device surface, the response current is measured and plotted on 2D images. The sensitivity exhibits very strong variations that are associated with the grain boundaries within the material. By varying the electric field, it appears that the signal does not increase linearly with the bias, revealing that carrier velocity saturation can be locally reached in some grains. Also, by varying the X-ray energy, the penetration depth could be varied in order to probe the material preferentially either in the volume or in the near-surface regions. [Copyright &y& Elsevier]

Abstract: In the framework of a multiannual experiment performed at Baia Terra Nova, Antarctica, size-segregated aerosol samples were collected by using a 12-stage SDI impactor (Hillamo design). Approximately 2800 particles, belonging to the first four supermicrometric SDI stages – 8.39, 4.08, 2.68, 1.66μm dynamic aerosol diameter cuts – were analyzed at the INFN-LNL micro-PIXE facility, a three lens Oxford Microprobe (OM) product, installed in the early nineties. Four regions on each of the 12 sub-samples were measured; 60 aerosol particles were detected on average in each of the analyzed regions. The off-line single aerosol particle (SAP) analysis of such big amount of data required software that is able to rapidly handle the acquired data, with a simple and fast area selection procedure; the subsequent automated PIXE spectra analysis with a specialized code was also needed. The MAPPIX 2.0 software was designed to make easier and faster the user jobs during the SAP analysis. The package is composed of two separate routines: the first one is devoted to data format conversion (OM-LMF file format to MAPPIX format), while the second one is devoted to micro-PIXE maps graphical presentation and aerosol particle selection procedure. The MAPPIX data format and software features will be discussed; a short report of the speed performances will be presented. [Copyright &y& Elsevier]

The monolithic silicon telescope technology allows to produce solid state microdosimeters. A detector constituted by a matrix of pixels (2 μm in thickness) coupled with a deeper stage (about 500 μm in thickness) was designed, developed and characterized by comparing its response against Tissue Equivalent Proportional Counters (TEPCs) in different irradiation fields, showing promising results. Each pixel of the ΔE stage is a thin diode of 9 μm in diameter delimited by a guard ring of 14 μm in diameter. The aim of this work is the study of the charge collection efficiency of the single pixel of the silicon microdosimeter by irradiating a prototype at the micro-beam facility of the Ion Beam Center - IBC of the University of Surrey. Different light ions were exploited (protons, lithium ions and carbon ions) and scanned on different positions on and around a single pixel of the detector. The results show that the charge generated by events on the sensitive region of the ΔE stage is completely collected, while a charge collection efficiency lower than one characterizes the region between the central pixel and its guard ring. The guard ring delimits properly the sensitive region: no signals arise from events outside the 14 μm in diameter ring. Nevertheless, the microdosimetric distributions of the different charged particles highlight a minor distortion in terms of the absorbed dose. This latter result justifies the good agreement with TEPCs in terms of microdosimetric distributions in different hadrons beams described in previous works. • Double-stage silicon telescope for microdosimetry applications. • Characterization of the charge collection efficiency with light ions. • The microdosimetric spectrum is slightly influenced by the partial charge collection. [ABSTRACT FROM AUTHOR]

Bismuth (Bi) content of electrum from Mongolian artisanal/small-scale mining sites was determined by micro-PIXE at CSIRO. This is to provide artisanal/small-scale miners information on the valuable trace element in electrum which they recover from quartz veins. The analysis was done using a 3 MeV micro-beam (30 micrometer in diameter) with an aluminum filter of 125 micrometer thickness. The result showed that electrum grains from the study area contains Bi with a range from 0 to 2,530 ppm. [ABSTRACT FROM AUTHOR]

Abstract The present study investigates nonlinear forced vibration of dielectric elastomer-based micro-beam. The nonlinear terms in beam equation are geometric and material one. Geometric nonlinearity is considered by von-Karman strain displacement relationship and the material nonlinearity is modeled with Yeoh hyper-elastic model. Galerkin and Multiple scale methods solve the governing equation. This solution that includes primary resonance, leads to frequency response, so that we depict influence of detuning parameter on amplitude in variation of different parameters.