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Photon-Counting Detectors for X-ray Imaging
Published in Paolo Russo, Handbook of X-ray Imaging, 2017
In 1998, the Swiss Light Source (SLS) synchrotron and the Paul Scherer Institute (PSI) joined efforts to develop a large area photon counting chip for X-ray experiments at SLS. Pilatus I was prototyped in 2002, featuring a 80 mm × 36 mm monolithic Si sensor (300 μm thick) bump-bonded to a mosaic-tiling of 2 × 8 Pilatus I ASICs (Brönnimann et al. 2003), and a subsequent larger version offering a 21 cm × 24 cm imaging area (Broennimann et al. 2006). However, to overcome a number of shortcomings related to this design, a second version was developed. The Pilatus II chip (Kraft et al. 2009) was a 60 × 97 pixel matrix with a 172 μm pitch, using a commercial 0.25 μm CMOS process. The individual chips can be tiled in a 2 × 8 configuration to form a so-called Pilatus II module. These modules can be further tiled to achieve larger areas. The largest Pilatus II assembly features 6 million pixels, covering a 43 cm × 45 cm imaging area (Kraft et al. 2009). The chip is bump-bonded to a 320-μm thick Si sensor. Each pixel cell of the Pilatus II chip comprises a preamplifier, with high and low gain setting, a shaper, and a single threshold discriminator, followed by a 20-bit counter. The single threshold of the discriminator can be adjusted by a 6-bit in-pixel ADC, reducing the threshold dispersion from 343 eV to ∼50 eV over 105 pixels. The high count rate requirements for synchrotron applications made it necessary to develop a count rate correction algorithm to reduce the dead time losses at high fluxes (Trueb et al. 2012).
Detector Interface Circuits for X-Ray Imaging
Published in Krzysztof Iniewski, Circuits at the Nanoscale, 2018
At the same time, the similar solution of the readout electronics for pixel detector has been developed for the x-ray measurements at the beamlime of the Swiss Light Source (SLS), as a part of the PILATUS (PIxeL ApparaTUs for the SLS) project [15,83–85]. The goal of this project was to build a hybrid pixel system covering approximately the area of 40 x 40 cm2 with 2000 × 2000 pixels. The first generation PILATUS I chip was designed in 2000 at the Paul Scherrer Institut (PSI), Villigen, Switzerland, using DMILL radiation-tolerant CMOS process (Atmel Temic SA, Nantes, France).
Influence of particle size of mesoporous silica composite nanoparticles coated with pH/temperature responsive copolymer on ibuprofen release behaviors
Published in Journal of Dispersion Science and Technology, 2022
Xiaoqi Jin, Mingwen Xiong, Linlin Zhu, Liyuan Zhang, Zhong Wu
The small-angle X-ray scattering (SAXS) experiments were performed at the Beijing Synchrotron Radiation Facility, and SAXS curves were recorded with a slit-collimated Kratky compact small-angle system with a two-dimensional Pilatus 1 M-F detector (hybrid pixel, DECTRIS, Switzerland). A bending cylindrical mirror coated with rhodium downstream from the monochromator with energy fixed at 8.052 keV is used to slit-collimated beam. The powder samples were supported on an adhesive tape for measurement. The scattering from adhesive tape was used for background correction for the samples. The SAXS detector was set to 1.55 m distance from the sample, and the experimental condition is under room temperature (22 °C). The wave vector q-range is between 0.09–3.0 nm−1. It has been reported that the mass fractal dimension (Dm) can be obtained in the range of 0 < ɑ < 3, Dm = ɑ, while, the surface fractal dimension (Ds) in the range of 3 < ɑ < 4, Ds = 6-ɑ (Ds ≠ 3).[21]
Pluronic-based lamellar phases: influence of polymer architecture on bilayer bending elasticity
Published in Molecular Physics, 2021
Sören Großkopf, Peter Fouquet, Lars Wiehemeier, Thomas Hellweg
Small angle x-ray scattering (SAXS) experiments were performed at 20 C on an in-house SAXS/WAXS system (XEUSS, Xenocs, Sassenage, France) with a CuK source ( Å, GeniX Ultra low divergence, Xenocs, Sassenage, France) and a Pilatus 300 k hybrid pixel detector (Dectris, Baden Deattwil, Switzerland). The covered q range is 0.02 to 0.2 Å. The data were analysed using the Foxtrot software (Version 3.3.4, G. Viguier, R. Girardot). The sample scattering was normalised with respect to incident intensity, sample thickness, measuring time, transmission and background. The scattered intensity was brought to absolute scale using glassy carbon (type 2, sample P11[21]) as standard. In SAXS experiments, the scattered intensity depends on the number of particles N, the incident intensity , the scattering volume of the sample V, the electron density difference , on the particle form factor P(q), and the structure factor S(q). The experimental data were treated using the software GIFT of the PCG software package provided by O. Glatter[22, 23].
Electrospun PCL-protein scaffolds coated by pyrrole plasma polymerization
Published in Journal of Biomaterials Science, Polymer Edition, 2019
Yeyzon Cruz, Efrén Muñoz, E. Y. Gomez-Pachón, Juan Morales-Corona, Jesús Olayo-Lortia, Roberto Olayo, Roberto Olayo-Valles
The morphology of the scaffolds was characterized with a high-resolution scanning electron microscope (SEM, Jeol JSM-7600F) with a field emission source. The diameter of the fibers was determined using the ImageJ software (NIH), and histograms and lognormal distribution fits were performed with the Igor Pro software package (version 6.37, Wavemetrics). Chemical characterization was performed in a Fourier transform infrared (FTIR) spectrometer (SpectrumG, Perkin-Elmer) equipped with an attenuated total reflection accessory. The crystalline structure of the samples was studied by wide-angle (WAXS) and small-angle X-ray scattering (SAXS) in a Xeuss (Xenocs) instrument equipped with a Cu Kα source (Genix3D) and a hybrid pixel detector (Pilatus 300 K, Dectris). Thermogravimetric analysis was done with a Pyris 1 TGA balance (Perkin Elmer) running in nitrogen atmosphere. The heating ramp was 10 °C/min, from 25 to 700 °C. Differential scanning calorimetry (DSC) was performed with a 2920 MDSC V2.6A (TA Instruments) using nitrogen as purge gas (flowrate 50 mL/min). Samples were analyzed by a heat/cool/heat method in a range of 20 °C to 250 °C at a 10 °C/min heating and cooling rate. The degree of crystallinity was calculated according to Equation 1: where is the heat of fusion measured by DSC and is the heat of fusion of 100% crystalline PCL (139.5 J/g) [14].