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Magnetically impelled arc butt (MIAB) welding is a solid phase pressure welding process similar to flash-butt welding, but it uses a magnetic field to rapidly spin the arc. The spinning arc provides a more consistent interior and exterior weld flash than typically seen on the flash-butt upset areas. MIAB welding process is presently being employed for welding tubular sections in automobile industries in various parts of United Kingdom and Germany. However, there are no details reported in available literatures on application of MIAB welding process for pressure parts. Hence, in this study, a pivotal attempt is being made to employ MIAB welding process to weld carbon steel tubes (51 mm and 44 mm outer diameter) and (5-6 mm thick) in economizer coils of pressure vessel. Several trials are conducted to create an optimal parameter window for MIAB welding process by varying the different input parameters. Further, mechanical testing and metallurgical characterization are carried out on the MIAB-welded specimen to evaluate its strength and to assess the weld integrity. The results of the experiment emphasized that the MIAB-welded joints exhibited high strength and good weld integrity. [ABSTRACT FROM PUBLISHER]

Abstract: Pulse intensities greater than 1017 Watt/cm2 were reached at the FLASH soft X-ray laser in Hamburg, Germany, using an off-axis parabolic mirror to focus 15 fs pulses of 5–70 μJ energy at 13.5 nm wavelength to a micron-sized spot. We describe the interaction of such pulses with niobium and vanadium targets and their deuterides. The beam produced craters in the solid targets, and we measured the kinetic energy of ions ejected from these craters. Ions with several keV kinetic energy were observed from craters approaching 5 μm in depth when the sample was at best focus. We also observed the onset of saturation in both ion acceleration and ablation with pulse intensities exceeding 1016 W/cm2, when the highest detected ion energies and the crater depths tend to saturate with increasing intensity. A general difficulty in working with micron and sub-micron focusing optics is finding the exact focus of the beam inside a vacuum chamber. Here we propose a direct method to measure the focal position to a resolution better than the Rayleigh length. The method is based on the correlation between the energies of ejected ions and the physical dimensions of the craters. We find that the focus position can be quickly determined from the ion time-of-flight (TOF) data as the target is scanned through the expected focal region. The method does not require external access to the sample or venting the vacuum chamber. Profile fitting employed to analyze the TOF data can extend resolution beyond the actual scanning step size. [Copyright &y& Elsevier]

The article offers information on the development of Drehort Neubrandenburg Online. It notes that the audiovisual language learning is based on a documentary film material which scenes took place in Neubrandenburg, Germany. It mentions that the program was published through Project for International Communication Studies (PICS). It states that the goals of producing the documentary includes capturing students' interest, authentic language, and short units of segments.

Introduction: Ultra-high dose rate (FLASH) radiotherapy has become a popular research topic with the potential to reduce normal tissue toxicities without losing the benefit of tumor control. The development of FLASH proton pencil beam scanning (PBS) delivery requires accurate dosimetry despite high beam currents with correspondingly high ionization densities in the monitoring chamber. In this study, we characterized a newly designed high-resolution position sensing transmission ionization chamber with a purpose-built multichannel electrometer for both conventional and FLASH dose rate proton radiotherapy., Methods: The dosimetry and positioning accuracies of the ion chamber were fully characterized with a clinical scanning beam. On the FLASH proton beamline, the cyclotron output current reached up to 350 nA with a maximum energy of 226.2 MeV, with 210 ± 3 nA nozzle pencil beam current. The ion recombination effect was characterized under various bias voltages up to 1000 V and different beam intensities. The charge collected by the transmission ion chamber was compared with the measurements from a Faraday cup., Results: Cross-calibrated with an Advanced Markus chamber (PTW, Freiburg, Germany) in a uniform PBS proton beam field at clinical beam setting, the ion chamber calibration was 38.0 and 36.7 GyE·mm 2 /nC at 100 and 226.2 MeV, respectively. The ion recombination effect increased with larger cyclotron current at lower bias voltage while remaining ≤0.5 ± 0.5% with ≥200 V of bias voltage. Above 200 V, the normalized ion chamber readings demonstrated good linearity with the mass stopping power in air for both clinical and FLASH beam intensities. The spot positioning accuracy was measured to be 0.10 ± 0.08 mm in two orthogonal directions., Conclusion: We characterized a transmission ion chamber system under both conventional and FLASH beam current densities and demonstrated its suitability for use as a proton pencil beam dose and spot position delivery monitor under FLASH dose rate conditions., (© 2021 American Association of Physicists in Medicine.)

Background: The "Controlled Aliasing In Parallel Imaging Results In Higher Acceleration" (CAPIRINHA) technique greatly accelerates T1w 3D fast low angle shot (FLASH) scans while maintaining high image quality. We studied image quality and conspicuity of inflammatory lesions on CAIPIRINHA-accelerated imaging for pediatric small-bowel magnetic resonance imaging (MRI)., Methods: Forty-four consecutive patients (mean 14±3 years, 18 girls) underwent small-bowel MRI (MR enterography, MRE) at 1.5 T including diffusion-weighted imaging (DWI), contrast-enhanced CAIPIRINHA 3D-FLASH and standard 2D-FLASH imaging. Crohn's disease (CD) was confirmed in 26 patients, 18 patients served as control. Independent blinded readings were performed for grading of image quality and conspicuity of CD lesions on CAIPIRINHA FLASH and standard FLASH images in comparison to a reference standard comprising imaging and endoscopic data., Results: CAIPIRINHA FLASH yielded significantly higher image quality with good inter-observer agreement (κ=0.68) and showed better visual delineation in 40% of the assessed bowel lesions, as compared to standard FLASH. There was full agreement for identification of CD patients between CAIPIRINHA and standard FLASH. CAIPIRINHA FLASH detected two small-bowel lesions that were not seen on standard FLASH. DWI revealed additional inflammatory lesions inconspicuous on contrast-enhanced imaging. MRE showed an overall diagnostic accuracy of 93%., Conclusion: We present first evidence that CAIPIRINHA greatly accelerates T1w imaging in paediatric MRE without trade-off in image quality or lesion conspicuity and is thus preferable to standard FLASH imaging.