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Er-Doped and Yb,Er-Doped CeF3-CaF2 disordered crystals were grown by temperature gradient technique ( TGT) method. The UV- VIS- NIR absorption spectra, near-infrared emission spectra, and the lifetime of 4 I13/2 level were measured. The infrared to visible upconversion emission of Er3+ was investigated in the grown crystals. The concentration distribution of doped ions was analyzed using ICP measurements. The efficiency of energy transfer from Yb3+ (2 F5/2) to Er3+ (4 I11/2) was about 88%. The experimental luminescence lifetime of the ~1.5 μm emission for CeF3-CaF2: Yb,Er crystal was 3.84 ms, and its quantum efficiency was 79%. [ABSTRACT FROM AUTHOR]

Abstract: Mg0.4Al2.4O4 single crystal was grown by the Czochralski method. The measured specific heat values are 0.804–1.06 J g−1 K−1 in the temperature range from 298.15 to 573.15 K. The calculated thermal conductivity components are 11.37, 11.47 and 10.77 W m−1 K−1 along the [111], [004] and [22̄0] direction at 298.15 K. The Vickers microhardness values are 1328–1414 kg mm−2. These experimental results show that Mg0.4Al2.4O4 crystal is a promising substrate for GaN-based LEDs. [Copyright &y& Elsevier]

β-Ga2O3 Schottky barrier diodes (SBDs) have been fabricated on a bulk (100) β-Ga2O3 substrate and tested as X-ray detectors in this study. The devices exhibited good rectification properties, such as a high rectification ratio and a close-to-unity ideality factor. A high photo-to-dark current ratio exceeding 800 was achieved for X-ray detection, which was mainly attributed to the low reverse leakage current in the β-Ga2O3 SBDs. Furthermore, transient response of the β-Ga2O3 X-ray detectors was investigated, and two different detection mechanisms, photovoltaic and photoconductive, were identified. The results imply the great potential of β-Ga2O3 based devices for X-ray detection. [ABSTRACT FROM AUTHOR]

Abstract: Mg0.4Al2.4O4 single crystals with good optical quality were successfully grown by the Czochralski method. The transmission spectrum indicated that the absorption edge of the crystal was at 220nm, while no apparent absorption peaks were found. The X-ray diffraction and DSC curve analysis showed that Mg0.4Al2.4O4 crystal was stable at room temperature. While after annealing in the air and hydrogen atmosphere at about 1200°C, Mg0.4Al2.4O4 decomposed into Al2O3 and (MgO)0.4(Al2O3) x (0.4< x <1.2). The reaction mainly occurred on the crystal surface, barely inside. [Copyright &y& Elsevier]

Abstract: Er-doped and Yb,Er-doped CeF3 single crystals were grown by Temperature Gradient Technique (TGT) method. The UV–VIR–NIR absorption spectra, near-infrared emission spectra, and 4I13/2 decay curves were measured. The infrared to visible up-conversion emission of Er3+ wasn’t observed in Yb,Er-doped CeF3 crystal. The efficiency of nonradiative energy transfer from Yb3+(2F5/2 level) to Er3+(4I11/2 level) was 43.3%. The measured luminescence lifetimes of the ∼1.5μm emission for CeF3:Yb,Er crystal was 1.91ms, with quantum efficiency up to 62%. [Copyright &y& Elsevier]

Background: Granulomatous lobular mastitis (GLM) is a chronic inflammatory breast condition characterized by an unclear etiology and an undefined therapeutic approach. Surgical intervention is considered an alternative modality for managing GLM. Staged operation is the predominant and characteristic surgical approach in the treatment of GLM in our center; therefore, we evaluated the efficacy of staged operative techniques in this cohort study., Methods: We retrospectively reviewed 212 patients with GLM who underwent staged operation between August 2020 and July 2022 in the inpatient department of our institute. Their clinical history information, clinic complaints, treatment details, surgical outcomes, follow-up results, and scores on the satisfaction questionnaire were analyzed. The patients were called for follow-up and consultation with a deadline of August 2023., Results: The median follow-up time was 27 months (range, 14-37 months). In total, 212 patients were treated with three different staged procedures according to the individual assessment and patient willingness, including 168 patients who underwent one-stage debridement operation and two-stage suture operation (DO + SO), 25 patients who underwent one-stage debridement operation without suture (DO), and 19 patients who underwent one-stage debridement and simultaneous suture operation (DSO). The median recovery time was 29 days (range, 14-60 days). A minority of patients developed postoperative complications, including effusion (1.89%), flap ischemia (0.94%), areola-nipple ischemia (0.94%) and sinus tract formation (2.36%). The scores of the satisfaction questionnaire were 43.10±3.09, and 186 patients (87.74%) gave high scores for postoperative breast appearance. Only 5 of 212 patients (2.36%) developed recurrence., Conclusions: Staged operation performed in our institute is an effective and safe surgical therapy in patients with GLM, yielding a short recovery time, low recurrence and good cosmetic results., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://gs.amegroups.com/article/view/10.21037/gs-23-386/coif). The authors have no conflicts of interest to declare., (2024 Gland Surgery. All rights reserved.)

We report on diode-pumped continuous wave and passively Q switched Er:GdScO 3 crystal lasers at around 2.8 µm. A continuous wave output power of 579 mW was obtained with a slope efficiency of 16.6%. Using Fe:ZnSe as a saturable absorber, a passively Q switched laser operation was realized. A maximum output power of 32 mW was generated with the shortest pulse duration of 286 ns at a repetition rate of 157.3 kHz, leading to a pulse energy of 204 nJ and a pulse peak power of 0.7 W.

The exploration of efficient self-powered solar-blind photodetectors is essential for applications in future sustainable optoelectronic systems. Herein, we demonstrate a photoelectrochemical (PEC)-type heterojunction-driven solar-blind detector constructed by atomic layer deposition (ALD) of oxygen vacancy-rich amorphous Ga 2 O 3 on three-dimensional urchin-like ZnO nanorod arrays (3D V O -Ga 2 O 3 /ZnO). The as-fabricated device achieves excellent solar-blind photodetection performance in terms of a high photoresponsivity of 7.97 mA W -1 at 0 V bias, an ultrahigh light to dark ratio of 6.93 × 10 4 under 266 nm light illumination as well as fast response and recovery times. The excellent performance originates from abundant oxygen vacancies in a-Ga 2 O 3 as donors, high specific surface area and good interface contact enabled by the 3D ordered nanostructure, and high carrier separation rates benefited from the Ga 2 O 3 /ZnO heterojunction. Our research offers a feasible and cost-effective approach towards the realization of a high-performance self-powered photodetection system for various applications.

β-Ga 2 O 3 semiconductor crystal is of wide band gap and high radiation resistance, which shows great potential for applications such as medical imaging, radiation detections, and nuclear physical experiments. However, developing β-Ga 2 O 3 -based X-ray radiation detectors with high sensitivity, fast response speed, and excellent stability remains a challenge. Here we demonstrate a high-performance X-ray detector based on a Fe doped β-Ga 2 O 3 (β-Ga 2 O 3 :Fe) crystal grown by the float-zone growth method, which consists of two vertical Ti/Au electrodes and a β-Ga 2 O 3 :Fe crystal with high resistivity. The resistivity of the β-Ga 2 O 3 :Fe crystal exceeds 10 12 Ω cm owed to the compensation of the Fe ions and the free electrons. The detector shows short response time (0.2 s), high sensitivity (75.3 µC Gy air -1 cm -2 ), and high signal-to-noise ratio (100), indicating great potential for X-ray radiation detection.

β-Ga 2 O 3 is a promising candidate as a fast scintillation crystal for radiation detection in fast X-ray imaging and high-energy physics experiments. However, total internal reflection severely limits its light output. Conventional photonic crystals can improve the light output, but such improvement decreases dramatically with increased scintillator thickness due to the strong backward reflection by the photonic crystals. Here, graded-refractive-index photonic crystals composed of nanocone arrays are designed and fabricated on the surfaces of β-Ga 2 O 3 crystals with various thicknesses. Compared to the conventional photonic crystals, there is still an obvious light output improvement by using the graded-refractive-index photonic crystals when the thickness of the crystals is increased by three times. The effect of thickness on the improved light output is investigated with numerical simulations and experiments. Overall, the graded-refractive-index photonic crystals are beneficial to the improvement of light output from thick scintillators.

β-Ga 2 O 3 is a new type of fast scintillator with potential applications in medical imaging and nuclear radiation detection with high count-rate situations. Because of the severe total internal reflection with its high refractive index, the light extraction efficiency of β-Ga 2 O 3 crystals is rather low, which would limit the performance of detection systems. In this paper, we use hollow nanosphere arrays with a high-index contrast to enhance the light extraction efficiency of β-Ga 2 O 3 crystals. We can increase the transmission diffraction efficiency and reduce the reflection diffraction efficiency through controlling the refractive index and the thickness of the shell of the hollow nanospheres, which can lead to a significant increase in the light extraction efficiency. The relationships between the light extraction efficiency and the refractive index and thickness of the shell of the hollow nanospheres are investigated by both numerical simulations and experiments. It is found that when the refractive index of the shell of the hollow nanospheres is higher than that of β-Ga 2 O 3 , the light extraction efficiency is mainly determined by the diffraction efficiency of light transmitted from the surface with the hollow nanosphere arrays. When the refractive index of the shell is less than that of β-Ga 2 O 3 , the light extraction efficiency is determined by the ratio of the diffraction efficiency of the light transmitted from the surface with the hollow nanosphere arrays to the diffraction efficiency of the light that can escape from the lateral surface.

There has been limited development in catalyst carriers for magnetic separations where superparamagnetic nanoparticles of a high saturation magnetization with no coercivity are required to isolate expensive catalyst reagent that are subjected to repeated magnetic cycles. By using simple stepwise layer-by-layer nanochemistry techniques, we show that an fcc FePt nanomagnet can be created inside each silica particle with tailored dimensions to great precision. Subsequent engineering of the external surface with Ti-O-Si species in an optimum structure to create a unique interface gives high activity and excellent selectivity of the composite material for the trans-stilbene oxidation to the corresponding epoxide in the presence of tert-butyl hydroperoxide. Thus, a new magnetic separable epoxidation catalyst is described. This work clearly demonstrates the significance of nanoengineering of a single catalyst particle by a bottom-up construction approach in modern catalyst design, which could lead to new catalytic properties.