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In this work, the electronic structure and optical properties of Zr-doped β -Ga2O3 with interstitial H and O vacancies were studied by using first-principles generalized gradient approximation combined with the Hubbard U method based on density functional theory. The energy band structure, density of states, absorption spectrum, effective mass, mobility and conductivity of the doped system were calculated and analyzed. Results showed that the doped system was more stable under the Ga-rich condition than under the O-rich condition. With the increase in Zr doping concentration, the bandgap of the β -Ga2O3 system gradually narrowed and the absorption spectrum of the system blue-shifted in the wavelength range of 162–275 nm. System conductivity was enhanced by Zr doping, decreased by O vacancies and greatly improved by interstitial H. Therefore, doping Zr into the β -Ga2O3 system is important for improving material properties and preparing electronic and optical devices. [ABSTRACT FROM AUTHOR]

Herein, the photoelectric properties of Ta‐doped β‐Ga2O3 are studied based on first‐principles density functional theory calculation. The effects of interstitial H and O vacancies on the properties of the system are also considered. The electronic structure, dielectric function, absorption spectrum, mobility, and conductivity of all the systems are studied and analyzed. The results show that Ta‐doped β‐Ga2O3 is an n‐type direct‐bandgap semiconductor. With the increase in Ta doping concentration, the dielectric constant, polarization ability, and charge binding ability of the system gradually increase, the bandgap gradually narrows, and the absorption spectra of systems redshift. The main absorption wavelengths of all systems are in the wavelength range of less than 300 nm. Therefore, Ta‐doped β‐Ga2O3 has an ultraviolet detection ability. The introduction of Ta is beneficial to improve the conductivity of the system. Interstitial H can improve the conductivity of the system. [ABSTRACT FROM AUTHOR]

In this work, the electronic structure and optical properties of Zr-doped β -Ga2O3 with interstitial H and O vacancies were studied by using first-principles generalized gradient approximation combined with the Hubbard U method based on density functional theory. The energy band structure, density of states, absorption spectrum, effective mass, mobility and conductivity of the doped system were calculated and analyzed. Results showed that the doped system was more stable under the Ga-rich condition than under the O-rich condition. With the increase in Zr doping concentration, the bandgap of the β -Ga2O3 system gradually narrowed and the absorption spectrum of the system blue-shifted in the wavelength range of 162–275 nm. System conductivity was enhanced by Zr doping, decreased by O vacancies and greatly improved by interstitial H. Therefore, doping Zr into the β -Ga2O3 system is important for improving material properties and preparing electronic and optical devices. [ABSTRACT FROM AUTHOR]

Herein, the photoelectric properties of Ta‐doped β‐Ga2O3 are studied based on first‐principles density functional theory calculation. The effects of interstitial H and O vacancies on the properties of the system are also considered. The electronic structure, dielectric function, absorption spectrum, mobility, and conductivity of all the systems are studied and analyzed. The results show that Ta‐doped β‐Ga2O3 is an n‐type direct‐bandgap semiconductor. With the increase in Ta doping concentration, the dielectric constant, polarization ability, and charge binding ability of the system gradually increase, the bandgap gradually narrows, and the absorption spectra of systems redshift. The main absorption wavelengths of all systems are in the wavelength range of less than 300 nm. Therefore, Ta‐doped β‐Ga2O3 has an ultraviolet detection ability. The introduction of Ta is beneficial to improve the conductivity of the system. Interstitial H can improve the conductivity of the system. [ABSTRACT FROM AUTHOR]

Objective: To investigate the relationship between condylar marrow signal abnormalities and temporomandibular joint internal derangement (TMJID)., Methods: Oblique sagittal T1 weighted MR imaging at closed and open mouth and Oblique sagittal T2 weighted MR imaging at closed mouth were obtained from 88 joints of 44 patients suffering from TMD. Condylar marrow signal abnormalities were reviewed and classified into bone marrow edema pattern (hypointense T1, hyperintense T2), sclerosis pattern (hypointense T1 and hypointense T2) and combined edema and sclerosis pattern., Results: Of 88 joints, 13 (14.8%) joints showed condylar marrow signal abnomalities, among which 11 belonged to edema pattern and, 1 was sclerosis pattern and the other was the combined patten. Of 13 joints with condylar marrow signal abnomalities, 11 (84.6%) had TMJID. Of 75 joints with normal marrow signal, 25 (33.3%) joints had TMJID. There was significant correlation between condylar marrow signal abnormalities and TMJID (P < 0.05)., Conclusion: Disc displacement is one of the factors inducing condylar marrow signal abnormalities. The pathological process from disc displacement to osteonecrosis requires further study.

Purpose: To investigate the relationship between condylar marrow signal abnormalities and joint pain., Methods: Oblique sagittal T1 and T2 weighted MR imaging at closed mouth was obtained from 88 joints of 44 patients who complained of unilateral TMJ pain. The condylar marrow signal of pain-free side served as self-control. All patients rated their pain levels by a visual analogue scale (VAS)., Results: Of 44 painful joints, 11(25% joints showed condylar marrow signal abnormalities, all of which were edema pattern. While there had condylar marrow signal abnormalities only in 2 (4.5%) of 44 pain-free TMJs. There was significant correlation between joint pain and condylar marrow signal abnormalities (P<0.01). The VAS score of patients with and without condylar marrow signal abnormalities was respectively 39.5+/-27.5 and 42.6+/-21.9, There was no correlation between them (P=0.696)., Conclusion: Temporomandibular joint pain is closely correlated with condylar marrow signal abnormalities, but the pain degree has no association with it.