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In this article, we present the first X-ray calibration performed over the 0.1–1.5 keV spectral range by means of a soft X-ray Manson source and the monochromator SYMPAX. This monochromator, based on a classical Rowland geometry, presents the novelty to be able to board simultaneously two detectors and move them under vacuum in front of the exit slit of the monochromatizing stage. This provides the great advantage to perform radiometric measurements of the monochromatic X-ray photon flux with one reference detector while calibrating another X-ray detector. To achieve this, at least one secondary standard must be operated with SYMPAX. This paper presents thereby an efficiency transfer experiment between a secondary standard silicon drift detector (SDD), previously calibrated on BESSY II synchrotron Facility, and another one (“unknown” SDD), devoted to be used permanently with SYMPAX. The associated calibration process is described as well as corresponding results. Comparison with calibrated measurements performed at the Physikalisch-Technische Bundesanstalt (PTB) Radiometric Laboratory shows a very good agreement between the secondary standard and the unknown SDD. [ABSTRACT FROM AUTHOR]

We developed a new scintillation timing detector using a proportional-mode silicon avalanche photodiode (Si-APD) for synchrotron radiation nuclear resonant scattering. We report on the nuclear forward scattering measurement on 61 Ni with a prototype detector using a lead-loaded plastic scintillator (EJ-256, 3 mm in diameter and 2 mm in thickness), mounted on a proportional-mode Si-APD. Using synchrotron X-rays of 67.41 keV, we successfully measured the time spectra of nuclear forward scattering on 61 Ni enriched metal foil and 61 Ni 86 V 14 alloy. The prototype detector confirmed the expected dynamical beat structure with a time resolution of 0.53 ns (FWHM). [ABSTRACT FROM AUTHOR]

The Eu 3+ -doped CaO-Gd 2 O 3 -SiO 2 -B 2 O 3 glasses were prepared to study photoluminescence, lasing potential and scintillation properties. Glasses absorb photons in ultraviolet, visible light and near infrared regions and are assigned to the energy transitions of Gd 3+ and Eu 3+ . Ultraviolet with 275 nm can generate the strong red emission with 614 nm via energy transfer form Gd 3+ to Eu 3+ . X-ray scintillation study exhibits strong emission pattern due to Gd-Eu energy transfer. The optimum concentrations of Eu 3+ ion in this glass is 0.30 mol% as it results maximum emission intensity. The fluorescence lifetime of the 5 D 0 level decreases from 1.763 to 1.726 ms when concentration increased from 0.05 to 0.40 mol%. From Judd-Ofelt analysis, this glass exhibit high potential for using as laser medium for red laser device with high lasing power and energy extraction ratio. Moreover, this glass performs the integral scintillation efficiency as 13% compared with BGO. [ABSTRACT FROM AUTHOR]

The present project will adopt the principle and technology of X-ray imaging to quickly measure the mass thickness (wherein the mass thickness of the item =density of the item × thickness of the item) of the irradiated items and thus to determine whether the packaging size and inside location of the item will meet the requirements for treating thickness upon electron beam irradiation processing. The development of algorithm of X-ray mass thickness detector as well as the prediction of dose distribution have been completed. The development of the algorithm was based on the X-ray attenuation. 4 standard modules, Al sheet, Al ladders, PMMA sheet and PMMA ladders, were selected for the algorithm development. The algorithm was optimized until the error between tested mass thickness and standard mass thickness was less than 5%. Dose distribution of all energy (1–10 MeV) for each mass thickness was obtained using Monte-carlo method and used for the analysis of dose distribution, which provides the information of whether the item will be penetrated or not, as well as the Max. dose, Min. dose and DUR of the whole item. [ABSTRACT FROM AUTHOR]

The electrical characteristics of the Ni/Cd 1 − x Zn x Te/In structures with a metal–semiconductor rectifying contact are investigated. The diodes, fabricated on the base of In-doped n -type Cd 1 − x Zn x Te (CZT) crystals with resistivity of ∼ 10 10 Ω ⋅ cm, have low leakage current and can be used as X/ γ -ray detectors. The rectifying contact was obtained by vacuum deposition of Ni on the semiconductor surface pretreated with argon plasma. The high barrier rectifying contact allowed us to increase applied reverse bias voltage up to 2500 V at the CZT crystal thickness of 1 mm. Dark (leakage) currents of the diodes with the rectifying contact area of 4 mm 2 did not exceed 3–5 nA at bias voltage of 2000 V and room temperature. The charge transport mechanisms in the Ni/CZT/In structures have been interpreted as generation–recombination in the space charge region within the range of reverse bias of 5–100 V and as currents limited by space charge at both forward and reverse bias at V >100 V. [ABSTRACT FROM AUTHOR]

Flexible and stretchable materials are increasingly being investigated for future technological platforms, polymer based materials being the most suitable candidates for those emerging technologies. This work reports on polymer based scintillator composites based on the thermoplastic elastomer Styrene-Ethylene/Butadiene-Styrene (SEBS) and Gd 2 O 3 :Eu 3+ scintillator nanoparticles, to form a polymer-based flexible and stretchable material for X-ray indirect detectors. Further, visible light yield under X-ray irradiation was improved by the inclusion of 2,5 dipheniloxazol (PPO) and (1,4-bis (2-(5-phenioxazolil))-benzol (POPOP) within the polymer matrix. Together with high levels of stretchability, with deformations up to 100%, the films exhibit suitable performance with low mechanical hysteresis (less than 1.5 MJ/m 3 for cycles up to 100% of strain) and reproducibly such as a scintillator material for the conversion of X-ray radiation into visible radiation. The decrease of just ∼13% of the X-ray radiation into visible light upon stretching up to 100% is attributed to a reduction of the effective filler concentration and proves the suitability of the developed materials for large area and stretchable X-ray radiation detectors. [ABSTRACT FROM AUTHOR]

In this work, laser-induced surface recrystallization process was developed to improve the surface properties and device performance of the polycrystalline PbI 2 thick films prepared by using close space vapor deposition method. A continuous polycrystalline PbI 2 recrystallized layer with a better mechanical strength and reflectivity improved from 2% to 4%–6% was obtained by this recrystallization process for the films with mechanical pretreatment. Other polytypes is absent in the recrystallized layer with the 2H-polytype remaining before and after treatment and obtaining improved electrical and X-ray photoelectric response performance. The pretreatment such as mechanical cutting/polishing and hydrogenation is necessary to lower the non-wetting crystallization behavior during the recrystallization process due to the rough surface state and oxygen contamination. [ABSTRACT FROM AUTHOR]

The progress in continuous downstream manufacturing of oral solid doses demands effective real-time process management, with monitoring at its core. This study evaluates the feasibility of using a commercial sensor to measure the mass flow rate of the particulates, a critical process variable in continuous manufacturing. The sensor independently measures X-ray attenuation and cross-correlation velocimetry of particulate flow in real time. Steady-state flow rates of blends comprised primarily of acetaminophen and microcrystalline-cellulose are monitored using the sensor, with simultaneous weighing scale measurements, to calibrate the sensor and investigate the measurement accuracy. The free-fall flow measurement of the powder and granule blends in a conduit is linearly proportional to the X-ray attenuation. Relative standard deviations of ∼3%-7% for 1 s monitoring are observed and a measurement error of approximately 5% suggests the usability of the sensor for real-time monitoring. The sensor measurement is robust for operational variations in composition, addition of lubricant or glidant and reuse of material for PAT tool calibration. The measurement relative standard deviations depend on particulate flow dynamics at the sensor location. This requires experimental evaluation for a given material at the sensor location, to capture the flow dynamics of the particulate stream through the sensor. [ABSTRACT FROM AUTHOR]

Differential cross section of X-ray production induced by O, Cl, Cu and Br ions with energies between 4 MeV and 40 MeV have been measured for thin targets of Ti, Fe, Zn, Nb and Ta in a direct way . A fully characterized silicon drift diode was used as X-rays detector. Beam currents have been measured by a system of two Faraday cups. Corrections for target thickness effects have been applied to the raw data. Experimental cross sections are compared both with theory and with previously published results. Experimental results from other authors are in reasonable agreement with ours over a wide energy range. Theory produces consistent results in the case of oxygen ions but gives cross sections even orders of magnitude below the experimental ones for heavier ions (ECPSSR-UA) or contrasting results (PWBA) depending on the ion-target combination. [ABSTRACT FROM AUTHOR]

In this paper, a novel type of icosahedron AuPd – copper oxide (CuO) core shell nanoparticles (AuPd@CuO NPs) – modified multi-walled carbon nanotubes (MWCNT) electrode for sensitive nonenzymatic glucose detection has been fabricated. AuPd@CuO core shell NPs were synthesized with icosahedron bimetallic AuPd nanocrystals as core and CuO nanoparticles (CuO NPs) as shell in a mild condition and a short time. MWCNT and AuPd@CuO NPs were characterized by field emission electron microscopy (FESEM), transmission electron microscope (TEM), energy dispersive X-ray detector (EDS) and Fourier transform infrared spectra (FT-IR). In this sensor, icosahedron AuPd@CuO NPs showed much higher electrocatalytic activity towards glucose oxidation. At an applied potential of +0.34 V, this sensor showed a good sensitivity of 744.98 μA mM −1 cm −2 to glucose. In addition, a linear range of 3.00 × 10 −5 to 9.31 × 10 −3 M ( R 2 = 0.997) was obtained with a detection limit of 0.10 μM ( S / N = 3). More importantly, the AuPd@CuO NPs/MWCNT modified electrode is highly resistant against poisoning by chloride ion and inference and was used to analyze glucose concentration in human serum samples. The modified electrode exhibits an enhanced electrocatalytic property, low working potential, good sensitivity, low detection limit, excellent selectivity, and good stability towards glucose oxidation, thus the AuPd@CuO NPs/MWCNT modified electrode is promising for the future development of nonenzymatic glucose sensors. [ABSTRACT FROM AUTHOR]

We review the high energy resolution off-resonant spectroscopy (HEROS) technique. HEROS probes the unoccupied electronic states of matter in a single-shot manner thanks to the combination of off-resonant excitation around atomic core states using wavelength dispersive X-ray detection setups. In this review we provide a general introduction to the field of X-ray spectroscopy together with the specification of the available X-ray techniques and X-ray methodologies. Next, the theoretical description of the HEROS approach is introduced with a special focus on the derivation of the X-ray emission and X-ray absorption correspondence relation at off-resonant excitation conditions. Finally, a number of experimental HEROS reports are reviewed in the field of chemistry and material science. We emphasize the applicability of HEROS to pulsed X-ray sources, like X-ray free electron lasers, and support the review with experimental examples. The review is complemented with perspectives on and possible further applications of the HEROS technique to the field of X-ray science. [ABSTRACT FROM AUTHOR]

Ce 3 + –doped, Tb 3 + –doped and (Ce 3 + , Tb 3 + )–codoped BaO–Gd 2 O 3 –Al 2 O 3 –B 2 O 3 –SiO 2 glasses were prepared by high temperature melting method and their luminescence properties have been investigated under UV excitation. Ce 3 + –doped borosilicate glass has a strong purplish–blue emission with the maximum about at 399 nm. Tb 3 + –doped borosilicate glass shows bright green emission at about 545 nm. (Ce 3 + , Tb 3 + )–codoped borosilicate glasses present a broad band emission ranging from 350 to 475 nm except emitting light at about 490, 545, 588 and 624 nm. There is an effective energy transfer from Ce 3 + ion to Tb 3 + ion and Ce 3 + ion strongly sensitizes the luminescence of Tb 3 + ion in (Ce 3 + , Tb 3 + )–codoped borosilicate glasses. A fast luminescence decay time of Tb 3 + ion is in an order of ms in (Ce 3 + , Tb 3 + )–codoped borosilicate glasses, which indicates it could be useful for X–ray detection for slow event. [ABSTRACT FROM AUTHOR]

The first results on betatron radiation obtained in laser-plasma acceleration experiments at the FLAME laser facility are presented. The diagnostic apparatus for the X-ray detection available at the facility is described together with the experimental setup for the generation of betatron radiation. [ABSTRACT FROM AUTHOR]

Two commercial-off-the-shelf (COTS) 4H-SiC UV photodiodes have been investigated for their suitability as low-cost high temperature tolerant X-ray detectors. Electrical characterisation of the photodiodes which had different active areas (0.06 mm 2 and 0.5 mm 2 ) is reported over the temperature range 0 °C to 140 °C together with measurements of the X-ray photocurrents generated when the detectors were illuminated with an 55 Fe radioisotope X-ray source. The 0.06 mm 2 photodiode was also investigated as a photon counting spectroscopic X-ray detector across the temperature range 0 °C to 100 °C. The depletion widths (at 120 V reverse bias) of the two diodes were found to be 2.3 µm and 4.5 µm, for the 0.06 mm 2 and 0.5 mm 2 detectors respectively, at 140 °C. Both devices had low leakage currents (<10 pA) at temperatures ≤40 °C even at high electric field strengths (500 kV/cm for 0.06 mm 2 diode; 267 kV/cm for 0.5 mm 2 diode). At 140 °C and similar field strengths (514 kV/cm for 0.06 mm 2 diode; 269 kV/cm for 0.5 mm 2 diode), the leakage currents of both diodes were <2 nA (corresponding to leakage current densities of 2.4 µA/cm 2 and 0.3 µA/cm 2 for each diode respectively). The results demonstrated that both devices could function as current mode detectors of soft X-rays at the temperatures <80 °C and that when coupled to a low noise charge sensitive preamplifier, the smaller diode functioned as a photon counting spectroscopic X-ray detector at temperatures ≤100 °C with modest energy resolution (1.6 keV FWHM at 5.9 keV at 0 °C; 2.6 keV FWHM at 5.9 keV at 100 °C). Due to their temperature tolerance, wide commercial availability, and the radiation hardness of SiC, such detectors are expected to find utility in future low-cost nanosatellite (cubesat) missions and cost-sensitive industrial applications. [ABSTRACT FROM AUTHOR]

The application of deep learning to X-ray image classification and recognition has attracted increasing attention in intelligent radiographic testing. In this study, we developed a defect detection method for X-ray images of aeroengine turbine blades using a novel unsupervised adversarial learning strategy. A defect detection model is proposed based on a generative adversarial network (GAN), which consists of a generator network, a discriminator network, and an extra encoder network. Employing an encoder–decoder–encoder subnetwork in the generator network enables the model to map an input image to a low-dimensional encoding vector, which is subsequently used to reconstruct the input image. The extra encoder network mapped the reconstructed image to a new encoding vector. Model training is implemented with non-defective X-ray image samples by minimising the distance between the original input image and the generated image (reconstruction loss) and the encoding vector distance (encoding loss). Defect detection is achieved using a generator network that can reconstruct non-defect samples but cannot reconstruct those with defects well. The effects of input image size, number of encoding nodes, and type of reconstruction loss on the performance of the defect detection model were studied. Consequently, the proposed model with an input image size of 128 × 128, 600 encoding nodes, and L 2 reconstruction loss can achieve a detection accuracy of 0.911. This study proposes a method for developing intelligent radiographic testing techniques for the quality management of aeroengines. [ABSTRACT FROM AUTHOR]

Silicon drift detectors (SDDs) with excellent energy resolution are widely used in the field of x-ray detection. Normally, the higher energy resolution of a SDD is mainly due to the lower capacitance compared with other silicon radiation detectors. It is worth noting that the energy resolution is also related to imperfect charge collection and ballistic deficit, which are susceptible to the device drift voltage. However, the maximum drift voltage is limited to twice the depletion voltage because of the reach-through effect in a classical SDD. In order to address this issue, a novel quasi-double-sided silicon drift detector (QD-SDD) was designed and fabricated by the thin film deposition technology. The so-called QD-SDD consists of a symmetrical drift ring structure on both the front and bottom sides. According to the simulation results, QD-SDD can be biased at a larger drift voltage, and thus building a larger drift electrical field than the classical single-sided SDD. Furthermore, the fabricated QD-SDD sensors were characterized using a 55-Fe radioactive source. The energy resolution at the 5.9 keV Mn Kα line can be improved from 210 eV to 170 eV by increasing the bias voltage on the outermost drift ring on both sides from −80 V to −130 V. [ABSTRACT FROM AUTHOR]

In this paper, we present a multi-voltage threshold (MVT) digitizer using a time-varied threshold and investigate the feasibility of using this digitizer to develop the data acquisition system for photon-counting X-ray security inspection imaging. This digitizer compares the scintillation pulse with a preset time-varied voltage signal and records the time information of the intersections. As the amplitude of the threshold varies as a function of time, the voltage values of the intersections could be calculated using the recorded time, and the energy information could be extracted via the acquired time–voltage samples. Unlike the constant voltage thresholds MVT digitizer requiring multiple voltage comparators, this method needs only one voltage comparator, which notably reduces the complexity in configuration. We demonstrate the development of such an MVT digitizer using a sine signal threshold and evaluate its energy performance with a yttrium orthosilicate (YSO) scintillator and Silicon Photomultiplier (SiPM) detector (designed for X-ray detection). The digitizer obtains energy resolutions of 41.4%, 26.6%, and 25.5% at 30, 59.5, and 80.9 keV, respectively. For comparison, the YSO/SiPM detector is also evaluated with a high-speed oscilloscope, and measured energy resolutions are 40.6%, 26.5%, and 25.1% at 30, 59.5, and 80.9 keV, respectively. These results indicate that the proposed MVT digitizer using a time-varied threshold is a promising method for developing a YSO/SiPM-based photon-counting X-ray detector. [ABSTRACT FROM AUTHOR]

• Two-dimensional dendritic fractals of LZHS crystals. • Plant-like growing mode of layered LZHS polycrystalline structure. • Tiller mechanism of LZHS polycrystalline structure. • Hydrophobicity enhanced by dendritic fractal structure. Two-dimensional dendritic fractals of layered zinc hydroxide sulfate (LZHS) were allowed to grow on a porous ZnO substrate-coated glass slide in an aqueous ZnSO 4 solution through the dissolution-redeposition process. The generated LZHS seeds with polycrystalline structure gradually evolved into two-dimensional dendritic fractals with a diameter of 50∼100 μm through a plant-like growth mode involving tillering and the formation of layered tiller buds at branch ends. Such tiller mechanism is proposed to explain the evolution of LZHS fractals based on results obtained by the scanning electron microscopy, transmission electron microscopy, X-ray diffractometry, and energy dispersive X-ray detection. The synthesized polycrystalline LZHS fractals can be topologically converted into hierarchical nanostructured zinc oxide by thermal pyrolysis combined with an alkaline wash process. After the modification by octyltrimethoxysilane, the topological zinc oxide surfaces, corresponding to the immersion time of 2, 4 and 6 h, showed superhydrophobic property with a water contact angle of 153.4°, 157.6°, and 164.7°, respectively. The enhanced hydrophobicity of zinc oxide films compared with the porous ZnO substrate surface is mainly attributed to the topological fractal morphologies and hierarchical nanostructures. [ABSTRACT FROM AUTHOR]

• The pebble-like, hexagonal and worm-like grain of CdZnTe films were prepared. • The film morphology is closely related with the sputtering process parameters. • The conductive mechanism of the worm-like grain film is Poole–Frenkel behavior. • The hexagonal grain CdZnTe films have the largest lowest resistivity. The polycrystalline CdZnTe films are promising material for fabrication of X-ray detection and solar cells. In this study, a pebble-like grain, hexagonal grain and worm-like grain of CdZnTe films were prepared via radio frequency magnetron sputtering. The morphology and properties of CdZnTe films were then characterized using atomic force microscopy, 2-D grazing-incidence wide-angle X-ray scattering, Raman spectra, transmission spectra and current–voltage curves. Accordingly, the CdZnTe crystal cell was found to be haphazardly arranged in the pebble-like grain, consequently demonstrating less anisotropy. In addition, the pebble-like grain film possessed a higher resistivity in light of the reduced anisotropy. In regard to the worm-like grain and hexagonal grain films, most CdZnTe (111) crystal planes were noted to be parallel to the sample surface. The worm-like grain film had the lowest absorption coefficient within the visible light range. Furthermore, the hexagonal grain film was shown to have the largest particle size, best crystallinity and lowest resistivity. The conductive mechanism of CdZnTe films of different morphologies was also discussed. [ABSTRACT FROM AUTHOR]

In past years efforts have concentrated on the development of arrays of Silicon Drift Detectors for X-ray spectroscopy. This is in stark contrast to the little effort that has been devoted to the improvement of germanium detectors, in particular for synchrotron applications. Germanium detectors have better energy resolution and are more efficient in detecting high energy photons than silicon detectors. In this context, the detector consortium of the European project LEAPS-INNOV has set an ambitious R&D program devoted to the development of a new generation of multi-element monolithic germanium detectors for X-ray detection. In order to improve the performance of the detector under development, simulations of the different detector design options have been performed. In this contribution, the efforts in terms of R&D are outlined with a focus on the modelization of the detector geometry and first performance results. These performance results show that a signal-to-background ratio larger than 1000 can be achieved in the energy range of interest from 5 keV to 100 keV. [ABSTRACT FROM AUTHOR]

The study of Soft X-ray emission can be a source of fundamental information, particularly for what concerns tokamaks and plasma diagnostics, but also in general in the fields of high energy and nuclear physics. Detection systems based on Gas Electron Multipliers (GEM) technology can be of particular use in the context of X-ray analyses, being relatively low cost while maintaining good spatial and temporal resolution and capability to sustain high counting rates (up to MHz/mm2). The development of these new and improved detectors is thus of interest, especially in the research about diagnostic and control of machines for fusion energy. In this work, the performance of a new triple-GEM detector, characterized by an aluminum metallic coating on both layers of the GEM foils, is presented and a comparison is made with the more conventional design employing copper coating. The performances of an aluminum-coated GEM (Al-GEM) detector and of a standard copper-coated GEM (Cu-GEM) detector in revealing quasi-monochromatic X-ray beams coming from different fluorescence materials are compared. The Al-GEM detector is shown to less suffer the issue of unwanted background on the signal caused by the presence of copper inside the detector itself. The suppression of this noise source encourages the use of Al-GEM detectors to perform spectroscopy in harsh environments, such as tokamak machines, where soft X-rays are useful probes to control different plasma properties and parameters. [ABSTRACT FROM AUTHOR]

Lung nodule detection in chest X-ray (CXR) images is common to early screening of lung cancers. Deep-learning-based Computer-Assisted Diagnosis (CAD) systems can support radiologists for nodule screening in CXR images. However, it requires large-scale and diverse medical data with high-quality annotations to train such robust and accurate CADs. To alleviate the limited availability of such datasets, lung nodule synthesis methods are proposed for the sake of data augmentation. Nevertheless, previous methods lack the ability to generate nodules that are realistic with the shape/size attributes desired by the detector. To address this issue, we introduce a novel lung nodule synthesis framework in this paper, which decomposes nodule attributes into three main aspects including the shape, the size, and the texture, respectively. A GAN-based Shape Generator firstly models nodule shapes by generating diverse shape masks. The following Size Modulation then enables quantitative control on the diameters of the generated nodule shapes in pixel-level granularity. A coarse-to-fine gated convolutional Texture Generator finally synthesizes visually plausible nodule textures conditioned on the modulated shape masks. Moreover, we propose to synthesize nodule CXR images by controlling the disentangled nodule attributes for data augmentation, in order to better compensate for the nodules that are easily missed in the detection task. Our experiments demonstrate the enhanced image quality, diversity, and controllability of the proposed lung nodule synthesis framework. We also validate the effectiveness of our data augmentation strategy on greatly improving nodule detection performance. • Lung nodule synthesis framework disentangles nodule attributes to the shape, the size, and the texture, respectively. • Applying modulated shape mask provides diverse variation of nodule shape and quantitative control of nodule size. • Data augmentation based on the controllability of lung nodule synthesis effectively improves lung nodule detection. [ABSTRACT FROM AUTHOR]

Metal halide perovskites nanoparticles (PNPs) show promising application in X-ray detection and imaging. However, they exhibit poor stability, especially, the emission peak might be evidently shifted with increasing the PNPs concentration. In this work, the composites of CsPbBr 3 PNPs and BaLuF 5 : 15Gd/15Tb NPs are used to prepare scintillation film for the first time. When fixing the PNPs content in the film, its emission center is not changed after the addition of fluoride NPs. The uniform film containing both BaLuF 5 : 15Gd/15Tb to CsPbBr 3 is prepared. The scintillation intensity of the CsPbBr 3 PNPs is enhanced owing to the radiative energy transfer process from BaLuF 5 : 15Gd/15Tb to CsPbBr 3. Our results provide a novel route to improve the scintillation intensity, which might promote the exploration of new scintillators with high performance. • The composite of CsPbBr 3 and BaLuF 5 : Gd/Tb is used to prepare scintillation film. • The PL profile of CsPbBr 3 is not changed after the addition of fluoride NPs. • The RL intensity of CsPbBr 3 is enhanced owing to the radiative energy transfer. • The RL intensity of mixture is increased by ∼ 2.3 times compared to CsPbBr 3. [ABSTRACT FROM AUTHOR]

The Gd 2 Y (1-x) Dy x Al 2 Ga 3 O 12 phosphors were prepared by the solid state reaction to study in the structure, photon absorption, photo- and radioluminescence properties. The XRD represented a crystalline cubic with Ia 3 ‾ d space group as the main structure of phosphor. The Y atomic sites were fine replaced by Dy in phosphor structure with Dy content (x) in a range of 0.25–1.00. The grain sizes of phosphor samples observed by SEM were in several micrometers. In the absorption spectra, phosphors absorbed the photons with various wavelengths in UV, VIS and NIR region. Both direct Dy3+ excitation and Gd3+→Dy3+ energy transfer caused the strong photoluminescence (PL) of Dy3+ around 481 (4F 9/2 → 6H 15/2) and 582 (4F 9/2 → 6H 13/2) nm. The PL decay times of phosphors were around 0.10–0.74 ms. Phosphors performed the strong response to X-rays in radioluminescence (RL) spectroscopy which composed of the sharp emission of Dy3+ ion, broad emission of Y-related complex and weak emission of defects. Phosphor with 0.25 Dy content owned the highest PL and RL intensity of Dy3+ due to the concentration quenching effect and appropriate lattice constant, while free-Dy phosphor had the highest RL intensity of Y complexes. The Gd 2 Y 0.75 Dy 0.25 Al 2 Ga 3 O 12 phosphors is a promising material for the X-ray detection applications, especially the X-ray imaging screen. • X-ray detection ability from luminescence of Dy3+ ion and Y-complex. • Photoluminescence of Dy3+ surrounded by high-symmetry environment in phosphor. • Luminescence under the Gd3+ → Dy3+ energy transfer. • The influence of lattice constant on luminescence properties. [ABSTRACT FROM AUTHOR]

Cadmium Telluride (CdTe) films are directly deposited on a CMOS (complementary metal-oxide-semiconductor) based readout chip as sensor layer for X-ray detection. This is performed by using a modified Molecular Beam Epitaxy (MBE) setup with a carbon collimator enabling growth rates up to 10 µm/h. To obtain a good contacting behaviour of the 25–50 µm thick CdTe films, Te and Sb 2 Te 3 are additionally evaporated during the process. The investigation of polycrystalline sensor layers deposited at 400 °C with SEM (scanning electron microscopy) and XRD (X-ray diffraction) reveals a columnar growth of the individual grains oriented predominantly in (111). By PES (photoelectron spectroscopy) measurements the chemical composition of the different layers is identified in a depth profile and changes in work function along the contact structure are observed. Detector properties reveal a linear behaviour of the count rate with increasing radiation intensity as well as sensibility to holes and electrons. Spatial resolution measurements result in a resolution of 5 lp/mm, which is a mandatory requirement for medical applications. [ABSTRACT FROM AUTHOR]

During the blow-down stage of a loss of coolant accident (LOCA), fibrous material and associated debris are transported from the location of the pipe break to the sump system as core coolant flows through containment. A series of strainer modules are installed to restrict large debris from entering the sump system, which supplies coolant to the Emergency Core Cooling System (ECCS). The accumulation of fibrous and debris material can result in the formation of semi-porous layers on the strainer module surfaces and possibly result in a reduction of coolant recirculation to the ECCS. The University of New Mexico (UNM) is investigating non-invasive techniques to better visualize the formation of fibrous debris beds on sump strainer modules; real-time visualization of debris bed formation would allow for better assessment of the filtration blockage of sump strainers. A series of exploratory tests were performed at the Center for Non-Destructive Evaluation (CNDE) at Iowa State University (ISU) to determine the viability of using an X-ray system to perform in situ measurements of debris bed formation and particulate filtration on small-scale representative sump pump strainer assemblies. [ABSTRACT FROM AUTHOR]

In this article X-ray radiation sensitivity of ZnS thin film prepared by a chemical bath deposition technique has been reported. The films were prepared under 0.10, 0.15 and 0.20 molarity (M). Characterization reports show that the 0.20 M film has the best quality than the other low molarity films. I-V characteristics of the films were studied under dark condition and observed that the film prepared at 0.20 M has an electrical conductivity of 2.06×10 −6 (Ω cm) −1 which is about 10 times greater than the other lower molarity films. Further, the I-V characteristic of this film has studied under UV and X-ray radiations. The current under X-ray radiation is found to be significantly higher than that under the UV radiation. At a fix bias voltage of 1.0 V, the conductivity under UV radiation is found to be 3.26×10 −6 (Ω cm) −1 whereas that under the X-ray is 4.13×10 −5 (Ω cm) −1 . The sensitivity under X-ray radiation is significantly greater than that under the UV radiation. This analysis suggests that the ZnS thin film which is used as a UV radiation sensor can also be used as a potential X-ray radiation sensor. [ABSTRACT FROM AUTHOR]

Two X-ray detectors of similar sensitive volumes based on polycrystalline CVD diamond (pCVD) and single-crystal diamond (SCD) material respectively were tested and compared under fast pulsed X-rays, no significant difference was found in temporal response to fast pulsed X-rays. Considering high cost, small size and rareness of single crystal diamond, we propose to use polycrystalline diamond detectors in the detection of fast pulsed X-rays, that can find wider applications in comparison with single crystal diamond ones. [ABSTRACT FROM AUTHOR]

There is a great demand to develop non-destructive techniques to identify and quantify Special Nuclear Materials (SNM) in homeland security and nuclear safeguards applications. Passive assay could be extremely challenging in some scenarios. Active interrogation technique based on photofission has been identified as one of the promising approaches. In radiation detection system design based on such technique, it is highly desired to have abilities to accurately and efficiently simulate delayed γ-rays emitted from photofission reactions. In this work, simulation results were compared with measurement outcomes to demonstrate the capabilities and limitations of the code MCNPX 2.7.0 in the simulation of delayed γ-rays from photofission of uranium and plutonium samples. First, high-energy delayed γ-rays (E γ ~2.7–4.5 MeV) from photofission of 238 U were simulated and validated against the energy spectra measured in between linac pulses. Second, low-energy delayed γ-ray spectra (E γ ~0.6–2.7 MeV) measured with a list-mode system after irradiation of 239 Pu were used in the validation. [ABSTRACT FROM AUTHOR]

Five SiC Schottky photodiodes for X-ray detection have been electrically characterized at room temperature. One representative diode was also electrically characterized over the temperature range 20°C to 140 °C. The performance at 30 °C of all five X-ray detectors, in both current mode and for photon counting X-ray spectroscopy was investigated. The diodes were fabricated in an array form such that they could be operated as either a 2×2 or 1×3 pixel array. Although the devices showed double barrier heights, high ideality factors and higher than expected leakage current at room temperature (12 nA/cm 2 at an internal electric field of 105 kV/cm), they operated as spectroscopic photon counting soft X-ray detectors uncooled at 30 °C. The measured energy resolution ( FWHM at 17.4 keV, Mo Kα) varied from 1.36 to 1.68 keV among different diodes. [ABSTRACT FROM AUTHOR]

Accurate and reliable energy calibration of spectral x-ray detectors used in medical imaging is essential for avoiding ring artifacts in the reconstructed images (computed tomography) and for performing accurate material basis decomposition. A simple and accurate method for relative calibration of the energy thresholds on a multi-bin spectral x-ray detector is presented. The method obtains the linear relations between all energy thresholds in a channel by scanning the thresholds with respect to each other during x-ray illumination. The method does not rely on a model of the detector's response function and does not require any identifiable features in the x-ray spectrum. Applying the same method, the offset between the thresholds can be determined also without external stimuli by utilizing the electronic noise as a source. The simplicity and accuracy of the method makes it suitable for implementation in clinical multi-bin spectral x-ray imaging systems. [ABSTRACT FROM AUTHOR]

Experimental intrusion-extrusion isotherms of MgCl 2 •21H 2 O solution were recorded at room temperature on pure silica FER-type zeolite (Si-FER). The intrusion occurs at 195 MPa and the phenomenon is completely reversible with a slight hysteresis. The “Si-FER - MgCl 2 aqueous solution” system behaves like a spring. The material was deeply characterized before and after intrusion-extrusion experiments and no significant changes were observed. The unit cell parameters were refined – on the basis of the in situ synchrotron X-ray powder diffraction data - up to 1.47 GPa and then at P amb upon pressure release. The Rietveld refinement of the data collected at 0.28 GPa (280 MPa), a pressure close to the intrusion value, shows that both ions and water molecules present in the MgCl 2 aqueous solution were intruded in the porosities. However, the solvation degree of the intruded ions differs from the initial solution, revealing a partial desolvation of both magnesium and chloride ions. As a whole, the nature and amount of the intruded species correspond to a MgCl 2 •10H 2 O composition. Moreover, at a higher pressure (0.68 GPa), a phase transition from the orthorhombic P mnn to the monoclinic P 2 1 /n s.g. is observed in Si-FER. At 1.47 GPa, the zeolite maintains this monoclinic symmetry, while another phase transition, to the monoclinic P 2 1 s g., is argued from the analysis of the pattern of the sample compressed to 2.6 GPa and then collected upon pressure release to ambient conditions. [ABSTRACT FROM AUTHOR]

This paper develops an integrated navigation method based on the X-ray pulsar navigation (XNAV) system and an autonomous optical navigation system for spacecrafts. The X-ray pulsar navigation is implemented by using the difference between the measured and predicated pulse arrival time, which is calculated by comparing an observed pulse profile with a standard pulse profile. A problem arises from the X-ray signal processing in that the spacecraft’s orbit information, which may be unknown, is required to construct the observed pulse profile. The effect of the spacecraft orbit error on the accuracy of the pulse TOA (time of arrival) difference determination is analyzed. It is specified that the performance of the XNAV system may be degraded in the presence of large orbit error. In order to improve the navigation accuracy, an integrated navigation scheme is presented by fusing the measurement information of a X-ray detector and an ultraviolet optical sensor. The XNAV/optical integrated navigation system is effective to mitigate the effect of the spacecraft orbit error. The superiority of the presented scheme is illustrated through numerical simulations. [ABSTRACT FROM AUTHOR]

This paper reports the latest technological development on the Low Gain Avalanche Detector (LGAD) and introduces a new architecture of these detectors called inverse-LGAD (iLGAD). Both approaches are based on the standard Avalanche Photo Diodes (APD) concept, commonly used in optical and X-ray detection applications, including an internal multiplication of the charge generated by radiation. The multiplication is inherent to the basic n ++ –p + –p structure, where the doping profile of the p + layer is optimized to achieve high field and high impact ionization at the junction. The LGAD structures are optimized for applications such as tracking or timing detectors for high energy physics experiments or medical applications where time resolution lower than 30 ps is required. Detailed TCAD device simulations together with the electrical and charge collection measurements are presented through this work. [ABSTRACT FROM AUTHOR]

We have investigated a hard X-ray detector system using a combination of a plastic scintillator and multi-pixel photon counters (MPPC). Photomultiplier tubes (PMTs) have typically been adopted to read scintillators because of their high gain and large photoelectric surface, and studies on PMT and scintillator systems are well advanced. However, PMTs have limitations; for example, they are relatively large in size, require high voltage to operate, and cannot be used in strong magnetic fields. On the other hand, MPPCs do not have such limitations and instead possess high quantum efficiency and a large compact size. Therefore, we have studied a detector system that combines an MPPC with a plastic scintillator. The system is primarily intended to be used for polarization measurements of high-energy astrophysical objects. We achieved an energy threshold of as low as ~5 keV while operating the detector at low temperature (−10 °C), reading the signal with short integration time (50 ns), and using a low-noise MPPC. We also confirmed that the light yield of our MPPC+plastic scintillator system is comparable to that obtained using a conventional PMT to read the scintillator signal. Herein, we report test results and future prospects. [ABSTRACT FROM AUTHOR]

Scintillator based coded-aperture imaging has proven to be effective when applied for X- and gamma-ray detection. Adaptation of the same method for neutron imaging has resulted in a number of propitious systems, which could be potentially employed for neutron detection in security and nuclear decommissioning applications. Recently developed scintillator based coded-aperture imagers reveal that localisation of neutron sources using this technique may be feasible, since pulse shape discrimination algorithms implemented in the digital domain can reliably separate gamma-rays from fast neutron interactions occurring within an organic scintillator. Moreover, recent advancements in the development of solid organic scintillators make them a viable solution for nuclear decommissioning applications as they present less hazardous characteristics than currently dominating liquid scintillation detectors. In this paper existing applications of coded-apertures for radiation detection are critically reviewed, highlighting potential improvements for coded-aperture based neutron source localisation. Further, the suitability of coded-apertures for neutron imaging in nuclear decommissioning is also assessed using Monte-Carlo modelling. [ABSTRACT FROM AUTHOR]

To assess the potential cytostatic properties of Pt(II) complexes with 3-hydroxymethylpyridine (3-hmpy) as the only carrier ligand, novel cis -[PtCl 2 (3-hmpy) 2 ] ( 1 ) and trans -[PtCl 2 (3-hmpy) 2 ] ( 2 ) have been prepared. Elemental analysis, FTIR spectroscopy, multinuclear NMR spectroscopy and X-ray crystallography were used to determine their structures. Based on the results obtained with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay and clonogenic assay on T24 human bladder carcinoma cells (T24), the most potent compound 2 was further tested for cytotoxicity in human ovarian carcinoma cell lines - cisplatin sensitive (IGROV 1) and its resistant subclone (IGROV 1/RDDP). The cytotoxicity of compound 2 in IGROV 1/RDDP is comparable to cisplatin. Furthermore, compound 2 induced severe conformational changes in plasmid DNA, which resulted in a delayed onset of apoptosis in T24 cells, and higher amounts of Pt in tumours and serum compared to cisplatin. In addition, in vivo antitumour effectiveness was comparable to that of cisplatin with a smaller reduction of animals' body weight, thus demonstrating that it is a promising transplatin analogue which deserves further studies. [ABSTRACT FROM AUTHOR]

A multipurpose facility for low cross section measurements has been developed at Inter University Accelerator Centre, New Delhi, India. The facility consists of a multipurpose miniature chamber equipped with 1 m focal length normal incidence Monochromator and charge coupled device based detection system which has been aligned to realize the best resolution of the spectrometer. The chamber in this facility collects radiation 100 times more efficiently from the older system, without using any extra focusing mirror assembly. It is ensured to have the provision of mounting an X-ray detector and the spectrometer transverse to the beam direction simultaneously in the same chamber. The atomic spectroscopic studies can be performed by interaction of ions beams with both thin foil and gas targets. Provision for using photomultiplier tube instead of charge coupled device, is employed in the system depending on the condition of the source strength or other detection issues. We observed the essence of a very weak atomic phenomenon, a triply excited autoionizing forbidden transition, using the above facility to demonstrate its capability for measuring such low cross section phenomena. The present developed facility covers a large spectroscopic region from X-rays to the near infrared (0.1–10,000 Å). [ABSTRACT FROM AUTHOR]

The developments in synchrotron radiation based polymer research have been profound over the last two decades. Not only have many more beamlines suitable for soft condensed matter research become available since the pioneering days but also the technical developments with respect to X-ray beam quality and position sensitive X-ray detectors have been very substantial. This has allowed to increase the degree of experimental sophistication considerably by introducing sample environments which not only allow the materials to be studied outside of equilibrium conditions but in fact in conditions which closely start to resemble realistic processing conditions. These developments now allow polymer researchers to bring synchrotron radiation based tools to the whole spectrum from academic relevant characterisations to trying to understand the effects that desired processing parameters have on the final materials. In this manuscript, which is not intended as a comprehensive history, it is described how the historic interplay between technical developments and the experimental desires has generated the soft condensed matter synchrotron radiation toolbox that is at present available by following some of the major areas that have been the subject of polymers in the last two decades. [ABSTRACT FROM AUTHOR]

The Advanced Telescope for High-Energy Astrophysics (Athena) has been selected by ESA as its second large-class mission. The future European X-ray observatory will study the hot and energetic Universe with its launch foreseen in 2028. Microcalorimeters based on superconducting Transition-edge sensor (TES) are the chosen technology for the detectors array of the X-ray Integral Field Unit (X-IFU) on board of Athena. The X-IFU is a 2-D imaging integral-field spectrometer operating in the soft X-ray band (0.3–12 keV). The detector consists of an array of 3840 TESs coupled to X-ray absorbers and read out in the MHz bandwidth using Frequency Domain Multiplexing (FDM) based on Superconducting QUantum Interference Devices (SQUIDs). The proposed design calls for devices with a high filling-factor, high quantum efficiency, relatively high count-rate capability and an energy resolution of 2.5 eV at 5.9 keV. The paper will review the basic principle and the physics of the TES-based microcalorimeters and present the state-of-the art of the FDM read-out. [ABSTRACT FROM AUTHOR]

A series of novel alkyl 5-hydroxy-7-aryl-5-methyl-1,3-dioxo-2-phenyl hexahydropyrazolo[1,2- a ][1,2,4]triazole-6-carboxylates and alkyl 5-aryl-7-methyl-1,3-dioxo-2-phenyl-1,2,3,5-tetra hydropyrazolo[1,2- a ][1,2,4]triazole-6-carboxylates have been synthesized. The synthesis of hydroxy pyrazolo[1,2- a ][1,2,4]triazoles has been achieved by DBU mediated one pot reaction of aromatic aldehydes, alkyl acetoacetates and 4-phenylurazole at 35 °C in ethanol–water (1:1). Dehydration of hydroxy pyrazolo[1,2- a ][1,2,4]triazoles has been achieved using conc. H 2 SO 4 to afford dehydrated pyrazolo[1,2- a ][1,2,4]triazoles in high yields. The structural assignments have been made by spectral data and unambiguously confirmed by X-ray analysis. Good yields, operational simplicity and moderate conditions are the advantages of the reactions. [ABSTRACT FROM AUTHOR]

AgI incorporated perovskite X-ray detectors were fabricated based on the spray-coating technique. The effect of AgI incorporation on the optoelectronic properties was systematically investigated. With suitable amount of AgI content, metal halide perovskite exhibited improved crystallinity, charge carrier mobility, lifetime, and X-ray sensitivity. [Display omitted] • Perovskite thick films were fabricated via spray-coating process. • The effect of AgI incorporation was carefully evaluated and optimized. • X-ray detectors based on the spray-coated perovskite thick junctions were fabricated. • High X-ray sensitivity, low detection limit and fast response were achieved. Metal halide perovskites have emerged as a promising candidate for ionizing radiation detection, thanks to the facile fabrication, excellent optoelectronic properties and high attenuation coefficient. In order to fully absorb the incident X-ray photons, X-ray detectors require relatively thick active layers. However, it is challenging to obtain thick perovskite films based on conventional solution-based techniques, due to the limited solubility and viscosity of the perovskite precursors. In this work, we introduced spray-coating to deposit perovskite films on various substrates, and achieved tunable and thick films. On the other hand, the charge transport is another issue limiting the device performance of perovskite X-ray detectors. Compared with conventional inorganic semiconductors, hybrid perovskites possess relatively poor charge carrier mobility and lifetime. To address this issue, we incorporate AgI within the perovskite precursor, and systematically investigated their optoelectronic properties. It was found that the optimized AgI incorporated perovskite films exhibited the highest mobility-lifetime product, resulted X-ray sensitivity up to 3433 μGy air −1 cm−2 and ultra-low detection limit of 3.5 nGy air s−1, suggesting great potential for X-ray detection. [ABSTRACT FROM AUTHOR]

Recently, semiconductive polymeric materials have attracted attention as an active layer for detecting ionizing radiation because of their excellent properties such as flexibility, easy production, solution processability and low-cost production. This paper presents X-ray detection properties of Poly(3-hexylthiophene) (P3HT):Phenyl C61 butyric acid methyl ester (PCBM) blend structure with different PCBM loading ratios. P3HT:PCBM mixing ratio was changed from 1:0 to 1:2. Top contact of the pure and blend structured device were produced by using a solution based graphite ink. Devices were constructed with vertical bulk resistive architecture within an ohmic electrode structure as ITO/PEDOT:PSS/P3HT:PCBM/Graphite configuration. Graphite electrode was coated on the active layer with the spray coating method. All devices exhibited ohmic current-voltage (I–V) characteristics. The blend structured devices exhibited stable saw-tooth type behaviour in photocurrent responses against the on and off states of X-rays. Saw-tooth type responses could be evaluated as major evidence for a potential usage of organic electronic device technology direct radiation detectors. Although the best sensitivity value to X-ray was obtained with the blend structure with equal ratio, it was observed that the rise and decay times were shortened with the increase in the amount of PCBM in the blend structure from. [Display omitted] • P3HT:PCBM active layer based X Ray detectors. • Spray coated graphite electrode was used as the top ohmic contact for all devices. • P3HT:PCBM ratio was changed as (1:0), (1:0.5), (1:1), (1:2). • Best sensitivity value to X-ray was obtained with the blend structure with equal ratio of PCBM and P3HT (1:1). [ABSTRACT FROM AUTHOR]

The aims of this study is to improve the sensitivity of indirect X-ray detectors by investigating the properties and application of ternary-blended organic active layers. The ternary-blended active layers studied were composed of conjugated polymer PBDB-T-2F as the donor (D1), non-fullerene Y6 as the first acceptor (A1) and ITIC-4F as the second acceptor (A2). The structural similarity between the two acceptors allows the advantage formation of a homogeneous acceptor phase and results in good film morphology. Another advantage of our approach is the electrical and optical characteristics of the active layer can be modulated based on the mixing ratio of the two acceptors. To find the optimal ternary blending, the content of D1 was fixed while the A1:A2 content ratio was adjusted. The CsI (Tl) scintillator-coupled detector with an active layer of PBDB-T-2F:Y6:ITIC-4F = 1.0:0.6:0.4 achieved the highest sensitivity of 4.27 × 103 μC∙Gy air −1∙cm−2 giving respective improvements of 27.10% and 43.92% compared to binary-blend PBDB-T-2F:Y6 = 1:1 and PBDB-T-2F:ITIC-4F = 1:1. Next, the active layer's spin-coating conditions and the bias conditions were examined to further improve the sensitivity of the detector. Finally, the detector with a PBDB-T-2F:Y6:ITIC-4F = 1.0:0.6:0.4 active layer was shown to have the highest sensitivity of 5.42 × 103 μC∙Gy air −1 cm−2 at a bias of – 1.6 V with a 97 ± 2 nm thick active layer. The aims of this study are to improve the sensitivity of indirect X-ray detectors by investigating the properties of ternary-blended organic active layers. The structural similarity between the two acceptors allows the advantage formation of a homogeneous acceptor phase and results in good film morphology. Another advantage of our approach is the electrical and optical characteristics of the active layer can be modulated based on the mixing ratio of the two acceptors. The CsI (Tl) scintillator-coupled detector with ternary-blended active layer giving respective improvements of 27.10% and 43.92% compared to binary-blended active layer. [Display omitted] • To improve the sensitivity of the X-ray detector, a ternary-blend strategy was applied to the organic active layer. • The X-ray detector using ternary-blended active layer shown 27.10% and 43.92% higher sensitivity compared to their respective binary combinations (PBDB-T-2F:Y6 and PBDB-T-2F:ITIC-4F). • The indirect-type X-ray detector using PBDB-T-2F:Y6:ITIC-4F = 1.0:0.6:0.4 ternary-blended active layer was achieved a high sensitivity of 5.42 × 103 μC∙Gy air −1∙cm−2. [ABSTRACT FROM AUTHOR]

Developing efficient strategies to fabricate planar photoluminescence scintillators is of great importance to explore X-ray detectors with new platform. Rare-earth (RE) doped Lu 2 O 3 thin films are successfully fabricated by mild aqueous phase electrochemical deposition on ITO/glass substrates with low-temperature post-annealing treatment. The as-prepared Lu 2 O 3 :RE3+ (RE = Eu, Tb and Tm) thin films exhibit steerable thickness, high transparency in the visible-NIR range, and low transmittance at UV band mainly due to the oxygen-metal (O2--RE3+) charge transfer processes and the 4f-4f transitions of the RE3+. The Lu 2 O 3 :RE3+ thin films emit intense red, green and blue (RGB) photoluminescence, which mainly correspond to the 5D 0 -7F 2 transition of Eu3+, 5D 4 -7F 5 transition of Tb3+ and 1G 4 -3H 6 transition of Tm3+ respectively. Moreover, the transparent Lu 2 O 3 :RE3+ thin films also exhibit high sensitivity and linearity luminescence to the X-ray stimulation in a dose rate from 30 to 160 mGy s−1. This rapid and energy-saving synthesis show high efficiency to fabricate rare-earth doped thin-film with a tunable optical performance for optoelectrical application in the fields of solar light concentrators, agricultural light conversion thin films, biosensors, photodetectors and especially the X-ray detectors. [Display omitted] • The thickness of Lu 2 O 3 :RE3+ (RE = Eu, Tb and Tm) films prepared by electrodeposition is controllable. • The thin films exhibit high transparency at Visible-NIR band. • The Lu 2 O 3 :RE3+ thin films emit intense RGB photoluminescence upon UV light excitation. • The Lu 2 O 3 :RE3+ thin films exhibit high sensitivity and linearity to the X-ray. [ABSTRACT FROM AUTHOR]

Although biopsy-based necrosis rate is a golden standard for reflecting the sensitivity of bone tumor and guiding postoperative chemotherapy, it requires biopsy which is invasive and time-consuming. In this paper, we develop a new necrosis rate detection method using time series X-ray images instead of biopsy. To overcome the limitations of few-shot samples, the proposed method utilizes a Generative Adversarial Network with Long Short-term Memory to generate time series X-ray images. For further data expansion, an image-to-image translation network is applied for producing the initial images. These augmented data are treated as the training set of a 3D-Convolutional Neural Network classification model. Our method expands the few-shot bone tumor X-rays by 10 times, and approaches the necrotic rate classification result of biopsy, which is the state-of-the-art technique in the detection of few-shot bone tumor necrosis rate. Furthermore, it provides an efficient method to investigate the bone tumor necrosis rate in few-shot samples. • A deep learning method is proposed to detect necrosis rate with few-shot X-rays. • The Conv-LSTM-GAN network in our method is designed to generate bone tumor images. • Our method expands bone tumor images by 10 times and achieves biopsy-like results. [ABSTRACT FROM AUTHOR]

Semiconductor-based direct conversion X-ray sensors have widespread applications spanning from medical diagnosis to industrial inspection. However, current findings on X-ray detection based on perovskites shows high sensitivity but exhibit large leakage current and poor stability, thus, inhibiting them from commercialization. Highly stable AgBiS 2 with large attenuation coefficient (μ = 3.07 g cm−2 at 70 keV), shows excellent charge conversion due to its higher atomic number (Bi, Z = 83), and density (ρ = 7.02 g cm−3) was used for X-ray detection. Here, we approach to enhance the net sensitivity of AgBiS 2 by tailoring all three parameters by segregating micro/ nanocrystals of cerium oxide (CeO 2) at the AgBiS 2 grain boundary (GB) region. From the X-ray impinged photocurrent response, substantial GB segregation of n-CeO 2 at the AgBiS 2 interface leads to improved attenuation and promotes the conversion of multiple scattered X-ray photons into electrons by interacting with the adjacent grains, thus resulting in enhanced photocurrent generation. The sensitivity (S) and noise equivalent dose (NED) ratio were calculated to determine the lowest detectivity of the sensor with less generated noise signals. From these experimental findings, 10 % of n-CeO 2 segregation leads to an improvement in the sensitivity of AgBiS 2 to 29 μC mGy−1 cm−3. [Display omitted] • X-ray sensors were fabricated with micro/ nano CeO 2 segregated AgBiS 2 thick films. • Multiple scattered X-ray photons at the AgBiS 2 grain boundary region were effectively utilized by nano CeO 2 grains, resulting in higher charge carrier generation. • X-ray impinged photocurrent measurement revealed nano CeO 2 :AgBiS 2 presents record sensitivity 29.3 μC mGy−1 cm−3 for 7.97 mGy dose. [ABSTRACT FROM AUTHOR]

The K 2 O–Gd 2 O 3 –B 2 O 3 –P 2 O 5 glass doped with Dy 2 O 3 (Dy:KGPB) were synthesized by the melt-quenching technique. These glasses were subjected to characterize the physical, structure, optical and luminescence properties. It was observed that the density, molar volume and refractive index of glass increased with increasing Dy 2 O 3 concentration. The FTIR result confirmed the main glass network of B O B and P O P linkages those were degraded by adding Dy 2 O 3 modifier. Glasses absorbed photons in ultraviolet, visible light and near-infrared region. The photoluminescence under direct Dy3+ excitation performed the strong emissions at 574 and 482 nm corresponding to 4F 9/2 → 6H 13/2 and 4F 9/2 → 6H 15/2 transition, respectively. The Gd3+ excitation also caused strong emission of Dy3+ by the Gd3+-Dy3+energy transfer. Glass doped with 1.00 mol% of Dy 2 O 3 owned the highest emission intensity due to the concentration quenching. The lifetime of 4F 9/2 level was found to decrease with addition of Dy 2 O 3 content via dipole-diploe interaction between Dy3+ ion. Judd-Ofelt (J-O) intensity parameters were initially calculated and applied to evaluate the radiative parameters such as branching ratios, radiative transition probabilities, and stimulated emission cross-sections. The radioluminescence of glass was also investigated and found the scintillation efficiency around 15.6%, compared to BGO scintillator. The Dy:KGPB glass has an interesting potential for solid-state laser, LED and X-ray detection applications. • The energy transfer phenomenon was observed from Gd3+-Dy3+ ions. • The bright greenish-yellow emission was observed for present glasses. • Energy transfer parameter show increasing trend with increase in Dy3+ ions. • X-rays scintillation efficiency of glass was 15.6% compared to BGO scintillator. • CIE chromaticity diagram show greenish-yellow emission under UV lamp excitation. [ABSTRACT FROM AUTHOR]

Organometal halide perovskites have proven to be potential materials for X-ray detection due to their great photoelectric properties, high radiation attenuation and low-cost preparation. However, ion migration is one of the obstacles for its applications, especially, ion migration via surface is much easier in single crystal materials than bulk diffusion which could significantly degrade the device performances. In this paper, the KCl passivation layer is prepared by the thermal evaporation method and inserted between crystal and electrode The trap density and μ τ product of pristine and KCl passivated MAPbI 3 devices are compared, and the results demonstrate KCl as a passivation layer can effectively passivate the surface traps and improve electrical performance. The KCl passivated MAPbI 3 detector exhibits a high X-ray sensitivity of 3700 μ C Gy air − 1 cm −2 under −20 V bias. [ABSTRACT FROM AUTHOR]