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The work involves the utilizing of solid-state nuclear track detector CN-85, to study the irradiated impact through incident alpha particles at different angles (80°, 90°), and irradiation time (5) min, after etching with 2.5N of NaOH solution at 60°±1 C, for different etching time between (0.5-4) hr. The results showed that both D and L for CN-85 exhibited an enhancement when exposed to Alpha particles, the alpha-particle track diameters and Length increased with Etching time but it decreased with the increased Energy of alpha particles. The experiment results also show that the D and L were affected due to the exposure to alpha particles and incident angles. This study is the first-time investigation CN-85 Nuclear track detector experimentally under the impact of alpha particles and suitable polymer for the detection alpha particles. [ABSTRACT FROM AUTHOR]

CR-39 detector which covered with boric acid (H3Bo3) pellet was irradiated by thermal neutrons from (241Am - 9Be ) source with activity 12Ci and neutron flux 105 n . cm-2. s-1. The irradiation times -TD for detector were 4h , 8h , 16h and 24h . Chemical etching solution for detector was sodium hydroxide NaOH , 6.25N with 45 min etching time and 60 C° temperature . Images of CR-39 detector after chemical etching were taken from digital camera which connected from optical microscope . MATLAB software version 7.0 was used to image processing . The outputs of image processing of MATLAB software were analyzed and found the following relationships: (a) The irradiation time -TD has behavior linear relationships with following nuclear track parameters: i) total track number - NT ii) maximum track number - MRD (relative to track diameter - DT) at response region range 2.5 μm to 4 μm iii) maximum track number - MD (without depending on track diameter - DT) . (b) The irradiation time -TD has behavior logarithmic relationship with maximum track number - MA (without depending on track area - AT) . The image processing technique principally track diameter - DT can be take into account to classification of α-particle emitters , In addition to the contribution of these technique in preparation of nano- filters and nano-membrane in nanotechnology fields [ABSTRACT FROM AUTHOR]

Solid Nuclear Track Detectors (SNTDs), CR-39 type, are usually adopted to monitor radon gas concentrations. In order to characterize the detectors according to track geometrical parameters, detectors were irradiated inside a vacuum chamber by alpha particles at twelve energy values, obtained by different Mylar foils in front of a 241Am source. The alpha energy values were verified using a Si detector. After the exposure to the alpha particles, the detectors were chemically etched to enlarge the tracks, which were then analyzed by means of a semiautomatic system composed of an optical microscope equipped with a CCD camera connected to a personal computer to store images. A suitable routine analyzed the track parameters: major and minor axis length and mean grey level, allowing us to differentiate tracks according to the incident alpha energy and then to individuate the discrimination factors for radon alpha tracks. The combined use of geometrical and optical parameters allows one to overcome the ambiguity in the alpha energy determination due to the non-monotonicity of each parameter versus energy. After track parameter determination, a calibration procedure was performed by means of a radon chamber. The calibration was verified through an inter-comparing survey. [ABSTRACT FROM AUTHOR]

Indoor radon studies have been carried out in some dwellings of Berat district, Albania, using CR-39 type plastic track detectors for three months exposure. Berat, designated a UNESCO World Heritage Site in 2008, comprise a unique style of architecture with influences from several civilizations that have managed to coexist for centuries throughout the history. The study has been undertaken for the purpose of health risk assessments. The people are exposed to it for a long period of time in inner environments; radon may cause cancer in several organs but mainly in the lungs. The risk varies depending on where you live, the local underlying rocks and regional geology. The measurements of this study are performed during the winter and spring season. The indoor radon concentrations are found to vary from 59 to 150 Bq/m³. A good correlation is obtained between uranium concentration and radon exhalation in the soil. The annual average radon concentration at 90% of the values found are below the reference level recommended by the International Commission on Radiological Protection. [ABSTRACT FROM AUTHOR]

There is a great interest in the study of p-11B aneutronic nuclear fusion reactions, both for energy production and for determination of fusion cross-sections at low energies. In this context we performed experiments at CELIA in which energetic protons, accelerated by the laser ECLIPSE, were directed toward a solid Boron target. Because of the small cross-sections at these energies the number of expected reactions is low. CR39 Solid-State Nuclear Track Detectors (SSNTD) were used to detect the alpha particles produced. Because of the low expected yield, it is difficult to discriminate the tracks due to true fusion products from those due to natural background in the CR39. To this purpose we developed a methodology of particle recognition according to their direction with respect to the detector normal, able to determine the position of their source. We applied this to the specific experiment geometry, so to select from all the tracks those due to particles coming from the region of interaction between accelerated protons and solid boron target. This technique can be of great help on the analysis of SSNTD in experiments with low yield reactions, but can be also generally applied to any experiment where particles reach the track detector with known directions, and for example to improve the detection limit of particle spectrometers using CR39. [ABSTRACT FROM AUTHOR]

Our aim is to characterize curvatures empirically using a methodology previously applied to other localized disturbances in POFs. The effects of several curvature radii and turn angles have been analyzed. For each condition, angular dependent attenuation and diffusion are obtained to assess the effects of the curvature over the power distribution. From these two functions, we can construct a matrix to simulate the effects of the curvature independently from the input power distribution. The obtained matrices can predict the impact of bends on transmission properties. In particular, bending losses have been calculated and compared to experimental results to validate the model. [ABSTRACT FROM AUTHOR]

It is well known that radon daughters up to 214Po are the real contaminants to be considered in case of indoor radon contamination. Assemblies consisting of 6 circular bare sheets of CR-39, a nuclear track detector, with radius varying from 0.15 to 1.2 cm were exposed far from any material surface for periods of approximately 6 months in 13 different indoor rooms (7 workplaces and 6 dwellings), where ventilation was moderate or poor. It was observed that track density was as greater as smaller was the detector radius. Track density data were fitted using an equation deduced based on the assumption that the behavior of radon and its progeny in the air was described by Fick's Law, i.e., when the main mechanism of transport of radon progeny in the air is diffusion. As many people spend great part of their time in closed or poorly ventilated environments, the confirmation they present equilibrium between radon and its progeny is an interesting start for dosimetric calculations concerning this contamination. [ABSTRACT FROM AUTHOR]

Infrared (IR) optical properties of a wurtzite ZnO/GaN heterostructure on a wurtzite 6H-SiC substrate are characterized by a polarized IR reflectance spectroscopy. The relation between the reststrahlen features and the optical phonon modes of each individual layer are investigated. It is shown that the transverse magnetic polarized IR reflectance spectrum provides the least loss of information about the optical phonon frequencies of wurtzite crystal. By means of the standard multilayer optics technique and based on an anisotropic dielectric function model, polarized IR reflectance spectra of the studied structure are simulated. Numerical fitting procedure is applied to obtain the best fit of experimental and theoretical spectra. Finally, the optical phonon frequencies and the layers thicknesses of the studied structures are determined. [ABSTRACT FROM AUTHOR]

Electronic components used in high power applications must be able to deal with rough operating conditions, like frequent changes of temperature, mechanical stress and short-term electrical overload. An important factor in this context is the electronic packaging, especially the electrical interconnection between the die and the output pins. In order to evaluate the effects of thermo-mechanical stress on the electrical interconnections during the lifetime (which can be up to 25 years), a simulation using the finite-element method is the mainly used approach. Another possibility is to simulate stress cycles through applying an equivalent mechanical or electrical load with regards to the expected operating conditions. To evaluate the results of the stress simulation on the electrical interconnections, the chip package must be cut open and this implies mechanical stress. This paper presents a preliminary investigation for a non destructive evaluation of electrical interconnections in integrated circuits via magnetic imaging. [ABSTRACT FROM PUBLISHER]

The paper presents a low cost, compact, fiber optic sensor for measuring acceleration in environmentally harsh industrial applications. The sensor is based on the deformation of a cantilever measured through the variation of the propagation loss of a plastic optical fiber fixed on its surface. In order to enhance the sensitivity to bending, the fiber surface has been modified with grooves extending to part of the core. Preliminary experimental results have confirmed the feasibility of the proposed approach and the possibility to use the sensor both as an accelerometer and as a seismometer. [ABSTRACT FROM PUBLISHER]

A side optical actuation method is presented for a slender MR-compatible biopsy needle. The needle includes an active region with a shape memory alloy (SMA) wire actuator, where the wire generates a contraction force when optically heated by laser light delivered though optical fibers, producing needle tip bending. A prototype, with multiple side heating regions, demonstrates twice as fast an initial response compared to fiber tip heating when 0.8 W of optical power is applied. A single-ended optical sensor with a gold reflector is also presented to measure the curvature independently of temperature as a function of optical transmission loss. Preliminary tests with the sensor prototype demonstrate approximately linear response and a repeatable signal, independent of the bending history. [ABSTRACT FROM PUBLISHER]

One of the principle natural radiation resources is Granite which can be dangerous for human because of its radiations. Based on this fact, in this research we attempt to specify the activity amount of these natural radio nuclides, existing in Shir-kuh Granite of Yazd state. To specify the activity amount of this natural radio nuclides, it has been applied the measurement method of Gamma spectroscopy using high purity Germanium (HPGe) detector. [ABSTRACT FROM AUTHOR]

This document presents a low cost, compact, POF sensor for measuring acceleration in industrial applications. The sensor is based on the bending of a cantilever measured through the variation of the signal propagation loss in a fiber with sensitivity enhanced by perturbations in the core/cladding structure. Preliminary experimental results have confirmed the feasibility of the proposed approach both using the sensor as an accelerometer and as a seismometer. [ABSTRACT FROM AUTHOR]