The early development of a combined micro- and full-field X-ray fluorescence analysis system using white X-rays at PLS-II.

X-ray fluorescence (XRF) is widely used to analyze elemental distributions in samples. Micro-XRF (µ-XRF), the most basic conventional XRF technique, offers good spatial resolution through precise 2D scanning with a micrometre-sized X-ray source. Recently, synchrotron based XRF analysis platforms have achieved nano-XRF with highly focused X-rays using polycapillary optics or mirrors, leveraging the excellent coherence of synchrotron radiation.

Optimal Motion Control of a Capsule Endoscope in the Stomach Utilizing a Magnetic Navigation System with Dual Permanent Magnets.

We propose a method to control the motion of a capsule endoscope (CE) in the stomach utilizing either a single external permanent magnet (EPM) or dual EPMs to extend the examination of the upper gastrointestinal tract. When utilizing the conventional magnetic navigational system (MNS) with a single EPM to generate tilting and rotational motions of the CE, undesired translational motion of the CE may prevent accurate examination. We analyzed the motion of the CE by calculating the magnetic torque and magnetic force applied to the CE using the point-dipole approximation model.

Analysis of a silicon comb structure using an inverse Talbot-Lau neutron grating interferometer.

We describe an inverse Talbot-Lau neutron grating interferometer that provides an extended autocorrelation length range for quantitative dark-field imaging. To our knowledge, this is the first report of a Talbot-Lau neutron grating interferometer (nTLI) with inverse geometry. We demonstrate a range of autocorrelation lengths (ACL) starting at low tens of nanometers, which is significantly extended compared to the ranges of conventional and symmetric setups.

Neutron grating interferometer with an analyzer grating based on a light blocker.

We study an analyzer grating based on a scintillation light blocker for a Talbot-Lau grating interferometer. This is an alternative way to analyze the Talbot self-image without the need for an often difficult to fabricate absorption grating for the incident radiation. The feasibility of this approach using a neutron beam has been evaluated and experiments have been conducted at the cold neutron imaging facility of the NIST center for Neutron Research.

Reconstruction of Compton Edges in Plastic Gamma Spectra Using Deep Autoencoder.

Plastic scintillation detectors are widely utilized in radiation measurement because of their unique characteristics. However, they are generally used for counting applications because of the energy broadening effect and the absence of a photo peak in their spectra. To overcome their weaknesses, many studies on pseudo spectroscopy have been reported, but most of them have not been able to directly identify the energy of incident gamma rays.

Symmetric Talbot-Lau neutron grating interferometry and incoherent scattering correction for quantitative dark-field imaging.

We introduce the application of a symmetric Talbot-Lau neutron grating interferometer which provides a significantly extended autocorrelation length range essential for quantitative dark-field contrast imaging. The highly efficient set-up overcomes the limitation of the conventional Talbot-Lau technique to a severely limited micrometer range as well as the limitation of the other advanced dark-field imaging techniques in the nanometer regime. The novel set-up enables efficient and continuous dark-field contrast imaging providing quantitative small-angle neutron scattering information for structures in a regime from some tens of nanometers to several tens of micrometers.

Characterization of the phase sensitivity, visibility, and resolution in a symmetric neutron grating interferometer.

A symmetric Talbot-Lau neutron grating interferometer has been developed for achieving high phase sensitivity. The gratings for the interferometer have been designed by maximizing the intergrating distances available at the experimental facility and optimizing the period of the gratings. The phase sensitivity in a Talbot-Lau grating interferometer has been mathematically modeled and analyzed and compared with experimental data.

Multi-scale analyses of constituent phases in a trip-assisted duplex stainless steel by electron backscatter diffraction, in situ neutron diffraction, and energy selective neutron imaging.

Micrometer to centimeter scale analyses of the crystalline phase volume fractions in a trip-assisted duplex stainless steel were performed under loading using electron backscatter diffraction (EBSD), in situ neutron diffraction, and energy selective neutron imaging (ESNI) methods. In contrast to the localized investigations of EBSD, ESNI provides macroscopic spatial distributions in a volume-averaged manner over the entire specimen with a spatial resolution of about 65 μm. The ESNI shows that the martensite is concentrated on the necking region and estimates its volume fraction of 14% at a strain of 0.

Feasibility evaluation of a neutron grating interferometer with an analyzer grating based on a structured scintillator.

We introduce an analyzer grating based on a structured scintillator fabricated by a gadolinium oxysulfide powder filling method for a symmetric Talbot-Lau neutron grating interferometer. This is an alternative way to analyze the Talbot self-image of a grating interferometer without using an absorption grating to block neutrons. Since the structured scintillator analyzer grating itself generates the signal for neutron detection, we do not need an additional scintillator screen as an absorption analyzer grating.

PLASTIC SCINTILLATOR FOR RADIATION DOSIMETRY.

Inorganic scintillators, composed of high-atomic-number materials such as the CsI(Tl) scintillator, are commonly used in commercially available a silicon diode and a scintillator embedded indirect-type electronic personal dosimeters because the light yield of the inorganic scintillator is higher than that of an organic scintillator. However, when it comes to tissue-equivalent dose measurements, a plastic scintillator such as polyvinyl toluene (PVT) is a more appropriate material than an inorganic scintillator because of the mass energy absorption coefficient. To verify the difference in the absorbed doses for each scintillator, absorbed doses from the energy spectrum and the calculated absorbed dose were compared.

Fabrication and characterization of the source grating for visibility improvement of neutron phase imaging with gratings.

The fabrication of gratings including metal deposition processes for highly neutron absorbing lines is a critical issue to achieve a good visibility of the grating-based phase imaging system. The source grating for a neutron Talbot-Lau interferometer is an array of Gadolinium (Gd) structures that are generally made by sputtering, photo-lithography, and chemical wet etching. However, it is very challenging to fabricate a Gd structure with sufficient neutron attenuation of approximately more than 20 μm using a conventional metal deposition method because of the slow Gd deposition rate, film stress, high material cost, and so on.