[en] By analysis of the actual operating characteristics of pressurizer in pressurized water reactor (PWR) nuclear power plant and based on some reasonable simplification and basic assumptions, the quality and energy conservation equations about pressurizer' s steam zone and the liquid zone are set up. The purpose of this paper is to build a pressurizer model of two imbalance districts. Water level and pressure control system of pressurizer is formed though model encapsulation. Dynamic simulation curves of main parameters are also shown. At last, comparisons between the theoretical analysis and simulation results show that the pressurizer model of two imbalance districts is reasonable. (authors)

[en] Highlights: • Nanoporous GaN with propagation and/or widening of nanopores was fabricated. • Porosity within the etched layer increases with increasing etching depth. • Porosity can be evaluated by the Z scan of Raman spectroscopy. - Abstract: Propagation and/or widening of nanopores within the etched layers were usually observed by cross-sectional scanning electron morphology which is a destructive method for etched samples. In this study, nanoporous GaN with propagation and/or widening of nanopores fabricated using a UV-assisted electrochemistry etching procedure was studied using the Z scan of Raman spectroscopy. Comparison of nanoporous GaN with as-grown GaN showed that the strain relaxation and elastic modulus increases and decreases with increasing porosity within the etched layer, respectively. This work provides a new method for nondestructive and qualitative study on the porosity change within the etched layers of porous films

[en] Highlights: • Ternary Al_2_xIn_2_−_2_xO_3 films were prepared on the YSZ (1 0 0) substrates by MOCVD at 700 °C. • The lowest resistivity of 4.84 × 10"−"3 Ω cm was obtained for the sample with x = 0.2. • Excellent optical transparency in the UV and visible wavelength regions was achieved. • Tunable optical band gap from 3.67 to 4.73 eV was obtained. - Abstract: The ternary Al_2_xIn_2_−_2_xO_3 films with different Al contents of x [Al/(Al + In) atomic ratio] have been fabricated on the Y-stabilized ZrO_2 (YSZ) (1 0 0) substrates by the metal organic chemical vapor deposition (MOCVD) method at 700 °C. The influence of various Al contents (x = 0.1–0.9) on the structural, electrical and optical properties of the films have been investigated. Structural analyses revealed a phase transition from the bixbyite In_2O_3 structure with a single orientation along (1 0 0) to the amorphous structure as the Al content increases from 10% to 90%. The lowest resistivity of 4.84 × 10"−"3 Ω cm with a carrier concentration of 1.1 × 10"2"0 cm"−"3 and a Hall mobility of 11.74 cm"2 V"−"1 s"−"1 were obtained for the sample with x = 0.2. The average transmittances for the Al_2_xIn_2_−_2_xO_3 films in the visible range were all over 77% and the optical band gap of the films could be modulated from 3.67 to 4.73 eV

[en] Arterial spin labeling (ASL) utilizing the water in arteries as an endogenous contrast media is a functional magnetic resonance imaging with advantages of noninvasive, lower cost, simpler operation and repetition, and avoiding the potential side effects from exogenous contrast agents. Three-dimensional arterial spin labeling (3D-ASL) which is based on fast spin echo (FSE) spiral K space gathering can effectively overcome motion artifacts and magnetic susceptibility artifacts come from EPI. Compared with the conventional ASL, the main advantages of ASL are more wider image, better quality, faster gathering speed, more accurate signal location and so on. All of the mentioned advantages make it wider application than conventional ASL. The research progress and clinical application of 3D-ASL were reviewed. (authors)

[en] Highlights: • Al_2_xIn_2_−_2_xO_3 films were prepared on the Y-stabilized ZrO_2 (1 1 1) substrates by MOCVD at 700 °C. • A phase transition from the bixbyite In_2O_3 structure to the amorphous structure was observed. • The lowest resistivity of 4.7 × 10"−"3 Ω cm was obtained for the Al_0_._4In_1_._6O_3 film. • Tunable optical band gap from 3.7 to 4.8 eV was obtained. - Abstract: The ternary Al_2_xIn_2_−_2_xO_3 films with different Al contents of x [Al/(Al + In) atomic ratio] have been fabricated on the Y-stabilized ZrO_2 (1 1 1) substrates by metal organic chemical vapor deposition at 700 °C. The structural, electrical and optical properties of the films as a result of different Al contents (x = 0.1–0.9) were investigated in detail. With the increase of Al content from 10% to 90%, a phase transition from the bixbyite In_2O_3 structure with a single orientation along (1 1 1) to the amorphous structure was observed. The minimum resistivity of 4.7 × 10"−"3 Ω cm, a carrier concentration of 1.4 × 10"2"0 cm"−"3 and a Hall mobility of 9.8 cm"2 v"−"1 s"−"1 were obtained for the sample with x = 0.2. The average transmittances for the Al_2_xIn_2_−_2_xO_3 films in the visible range were all over 78% and the optical band gap of the films could be tuned from 3.7 to 4.8 eV

[en] Brookite titanium dioxide (b-TiO_2) films were successfully deposited on Y-stabilized ZrO_2 (110) substrates at different substrate temperatures (500–650 °C) by the metal organic chemical vapor deposition technique. The results of X-ray diffraction θ-2θ scan indicated that the b-TiO_2 film deposited at 550 °C had the best single crystalline quality, for which the heteroepitaxial relationship and the microstructure were identified by the X-ray diffraction Φ scan and high resolution transmission electron microscopy measurements. A schematic diagram was proposed to clarify the epitaxial growth mechanism. The composition, morphology and optical properties of the b-TiO_2 films have been investigated in detail.

[en] β-Ga₂O₃ films have been prepared on MgAl₂O₄ (1 0 0) substrates at different temperatures (550–700 °C) by metal–organic chemical vapor deposition (MOCVD). Microstructure analysis revealed that the sample deposited at 650 °C was the single crystal epitaxial film with the best crystallinities. The epitaxial relationship was β-Ga₂O₃ (1 0 0) || MgAl₂O₄ (1 0 0) with β-Ga₂O₃ [0 0 1] || MgAl₂O₄ 〈0 1 1〉. A schematic diagram was proposed to explain the domain structure in the film layer. The average transmittance for the films in the visible range was over 90%. An ultraviolet (UV)–green photoluminescence (PL) from about 350–600 nm was observed at room temperature (RT). The corresponding PL mechanisms were investigated. -- Highlights: • β-Ga₂O₃ films have been prepared on MgAl₂O₄ (1 0 0) substrates by MOCVD. • The growth mechanism of the four-fold rotation domain structure was explained. • The average transmittance of the films in the visible wavelength range exceeded 90%. • The PL spectrum revealed an UV-Green emission from 350–600 nm

[en] High-quality gallium Nitride (GaN) films were prepared by reactive annealing sputtered gallium oxide (Ga₂O₃) films on Si (1 1 1) substrates in flowing ammonia. X-ray diffraction, X-ray photoelectron spectroscopy, and the selected area electron diffraction patterns reveal that the films consist of hexagonal wurtzite GaN with c-axis orientated polycrystalline grains. Intense room-temperature photoluminescence peaked at 354 nm of the films is observed. The band gap of these films has a blueshift with respect to bulk GaN

[en] Gallium-doped tin oxide (SnO₂:Ga) films have been prepared on α-Al₂O₃ (0 0 0 1) substrates at 500 deg. C by the pulse mode metalorganic chemical vapor deposition (MOCVD) method. The relative amount of Ga (Ga/(Ga+Sn) atomic ratio) varied from 3% to 15%. Post-deposition annealing of the films was carried out at different temperatures for 1.5 h in ambient atmosphere . The structural, electrical, optical and photoluminescence (PL) properties of the films have been investigated as a function of annealing temperature. All the films have the rutile structure of pure SnO₂ with a strong (2 0 0) preferred orientation. A single ultraviolet (UV) PL peak near 337.83 nm was observed at room temperature for the 3% Ga-doped as-grown film and near 336 nm for the 15%-doped film, which can be ascribed to electron transition from the oxygen vacancy and interstitial Ga³⁺ donor levels to the acceptor level formed by the substitution of Ga³⁺ for the Sn site. After annealing, the luminescence spectra have changed a little bit, which is being discussed in detail.

[en] Gallium oxide (Ga₂O₃) films were deposited on MgO (100) substrates by metalorganic vapor phase epitaxy. Structure analyses showed that the films deposited at 550–700 °C were epitaxial β-Ga₂O₃ films with an out of plane relationship of β-Ga₂O₃(100)||MgO(100). The film deposited at 650 °C showed the best crystallinity and the microstructure of the film was investigated by high resolution transmission electron microscopy. A theoretical model of the growth mechanism was proposed and the in-plane epitaxial relationship was given to be β-Ga₂O₃[001]||MgO<011>. A four-domain structure inside the epitaxial film was clarified. The β-Ga₂O₃ film deposited at 650 °C showed an absolute average transmittance of 95.9% in the ultraviolet and visible range, which had an optical band gap of 4.87 eV. - Highlights: ► Beta Ga₂O₃ epitaxial films were deposited on MgO(100) substrate. ► A theoretical model of the growth mechanism was proposed. ► The transmittance of the film in the ultraviolet and visible region exceeded 95.9%.