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BackgroundPencil beam scanning (PBS) proton systems with a rotating gantry makes proton intensity modulation technology widely used for better protection of organs at risk, but it also brings greater challenges to the quality control of proton system.PurposeThis study aims to verify the accuracy of an XRV-124 cone-shaped scintillation detector and to investigate its feasibility for use in PBS quality assurance (QA) procedures.MethodsFirstly, according to the measurement principle of XRV-124, a single setup was implemented to measure the spot size, beam–X-ray coincidence, gantry angle, star-shot test, and mechanical accuracy simultaneously. Then, the spot size and beam–X-ray coincidence were determined at the isocenter using the XRV-124 for 70~240 MeV at increments of 10 MeV and at 30° increments for all gantry angles. The coincidence of the X-ray system and proton beam was evaluated in the X and Y directions of the International Electrotechnical Commission coordinate system (IEC). Finally, the spot size and coincidence results were compared with those of the widely used Lynx detector, whereas the gantry angle results were compared with those of the proton treatment console (PTC).ResultsThe spot sizes obtained using the XRV-124 and Lynx are in good agreement within 0.10 mm for each energy, and the results show the same trend with a maximum deviation of 0.18 mm and 0.11 mm in the IEC-X and -Y directions, respectively. The gantry angles are less than 0.2° compared to those of the PTC. For the star-shot test, the average 3D and 2D distances from the isocenter are 0.4 mm and 0.2 mm, respectively, meets the quality control requirements. The QA items can be completed in 90 min.ConclusionsThis method of this study has been successfully applied to the QA of Varian ProBeam proton radiotherapy system in Hefei ion medical center, indicating that XRV-124 cone-shaped scintillation detector can be widely used in the same type of proton radiotherapy system to improve the QA efficiency and reduce the human error caused by frequent positioning.

Organic perovskites are promising semiconductor materials for advanced photoelectric applications. Their fluorescence typically shows a negative temperature coefficient due to bandgap change and structural instability. In this study, a novel perovskite‐based composite with positive sensitivity to temperature was designed and obtained based on its inverse temperature crystallization, demonstrating good flexibility and solution processability. The supercritical drying method was used to address the limitations of annealing drying in preparing high‐performance perovskite. Optimizing the precursor composition proved to be an effective approach for achieving high fluorescence and structural integrity in the perovskite material. This perovskite‐based composite exhibited a positive temperature sensitivity of 28.563% °C−1 for intensity change and excellent temperature cycling reversibility in the range of 25–40 °C in an ambient environment. This made it suitable for use as a smart window with rapid response. Furthermore, the perovskite composite was found to offer temperature‐sensing photoluminescence and flexible processability due to its components of perovskite‐based compounds and polyethylene oxide. The organic precursor solvent could be a promising candidate for use as ink to print or write on various substrates for optoelectronic devices responding to temperature. A composite based on perovskite was created to demonstrate long‐term positive temperature sensitivity. It could be a great option for use in smart windows that respond quickly to temperature changes. Furthermore, it had the potential to be used as ink for printing or writing on different substrates for optoelectronic devices with good flexibility and solution processability. [ABSTRACT FROM AUTHOR]

Laser-processing technology has been widely used in the ultra-precision machining of diamond materials. It has the advantages of high precision and high efficiency, especially in the field of super-hard materials and high-precision parts manufacturing. This paper explains the fundamental principles of diamond laser processing, introduces the interaction mechanisms between various types of lasers and diamond materials, focuses on analyzing the current development status of various modes of laser processing of diamond, briefly discusses the relevant applications in diamond cutting, micro-hole forming, and micro-groove machining, etc., and finally discusses the issues, challenges, and potential future advancements of laser technology in the field of diamond processing at this point. [ABSTRACT FROM AUTHOR]