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Thomson scattering is one of the most important diagnostic methods for measuring plasma electron temperature (T e) and electron density (n e). In the diagnostic system, the polychromator is often used to analyze the spectral broadening and intensity of the detected scattered light. The performance of the avalanche photodiode (APD) used in the polychromator is greatly affected by the ambient temperature. The change of ambient temperature will seriously affect the accuracy of Thomson scattering diagnosis. Through experimental analysis, when the ambient temperature increases, the gain of APD will be significantly reduced, resulting in a significant deviation in electron density measurement. Taking the system response at an ambient temperature of 24.1 °C as reference, the deviation of electron density measurement varies from 43% to −16%, with the ambient temperature from 16.6 °C to 29.9 °C. However, the change of ambient temperature has little impact on the measurement of electron temperature. Detailed test of the polychromator shows that the estimated deviation of the electron temperature is within 3%. Due to the change of ambient temperature, the response of the detectors in each channel of the polychromator is inconsistent, which will cause random errors. The influence on electronic temperature calculation is analyzed by numerical simulation. [ABSTRACT FROM AUTHOR]

Summary: Background: Acne vulgaris is widespread across the world. Mapping the latest magnitudes and temporal trends of acne vulgaris provides the essential foundation for targeted public policies at the national, regional and global levels. Objectives: In compliance with the framework of the Global Burden of Disease Study 2019, this study aimed to summarize the incidence, prevalence, DALYs and the corresponding secular trends of acne vulgaris by sex and age group in 204 countries from 1990 to 2019. Methods: The average annual percentage change was calculated to depict the temporal trends in age‐standardized rates (ASRs) of acne vulgaris burden by region, sex and age. Results: Globally, it was estimated that there were 117·4 million [95% uncertainty interval (UI) 103·0–133.7] incident cases of acne vulgaris, 231·2 million (95% UI 208·2–255·5) prevalent cases and 5·0 (95% UI 3·0–7·9) million DALYs, with an increase of approximately 48% compared with 1990. Moreover, the overall ASRs of acne vulgaris increased by approximately 0·55% annually over the past three decades. We observed large disparities in ASRs of acne vulgaris with changing trends in sex, location and age. The ASR of acne vulgaris among women was around 1·3 times that of men, but the sex difference was narrowed because of the pronounced increase among men. The ASRs of acne vulgaris were higher in high‐income regions, but the increasing trend was more pronounced in other regions. Conclusions: The burden rate of acne vulgaris continues to increase in almost all countries. Understanding the specific characteristics of acne vulgaris burden is essential to formulate more effective and targeted interventions for controlling acne burden. Whatis already known about this topic?Acne vulgaris is a common skin condition affecting around 9·4% of the global population.However, there is a sparsity of studies that have taken a truly global, regional and national approach. Whatdoes this study add?Following the Global Burden of Disease Study framework, this study summarizes the global magnitudes of acne vulgaris burden along with the temporal trend.A pronounced acne vulgaris burden rate was observed in Western Europe, high‐income Asia Pacific and East Asia.The burden rate of acne vulgaris continued to increase in almost all countries, except for the USA, Poland, Germany and New Zealand. Linked Comment:L. Naldi. Br J Dermatol 2022; 186:605. Plain language summary available online [ABSTRACT FROM AUTHOR]

• Analyzing the propagation characteristics of non-Gaussian beam. • Designing an in-vacuum collection optics with stable safety shutter structure. • Developing a new compact polychromator suitable for multi-point measurements. A vertical edge Thomson scattering diagnostic system on HL-2 M Tokamak has been developed recently. A Nd: YAG laser (1064 nm, 0.6–2.0 J, 30 Hz, 15 ns) is used as the probe beam. The laser beam propagates vertically through the plasma region and the scattered light is observed horizontally. The combination of a half-wave plate and a polarized beam splitter is used for stray light suppression. A group of in-vacuum collection lens is designed to image the 400 mm scattered region onto the rectangular fiber arrays. The laser beam waist and vertical spatial resolution are 2 mm and 10 mm, respectively. Scattered light is imaged on the 2.20 × 2.86 mm (10 × 13) fiber optic bundle. The development of collection optics with a special designed safety shutter ensures a reliable scattered signal, where the solid angle at central field of view (FOV) is 0.018 sr. A compact polychromator is developed to measure the scattered light. Relative calibration of the filter response (1060 nm, 1052 nm, 1029 nm and 982 nm) and absolute calibration by nitrogen Raman scattering have been completed. In the 2022 plasma campaign of HL-2M, the scattering signal is measured at E 0 = 1.2 J, confirming the capability of the system for pedestal measurement in the future H-mode campaign. [ABSTRACT FROM AUTHOR]

Abstract In the present study, the effect of high current pulsed electron beam (HCPEB) surface treatments on the microstructure, composition, stress states and properties of a Mg-8Gd-3Y-0.5Zr alloy has been investigated. The surface layers showed different features in microstructure and residual stress states under different number of pulses. Such a variation is essentially due to the different level of the dissolution of β-Mg 5 (Gd,Y) particles in remelted layers and the impact from thermal stresses generated by HCPEB treatments. The results have shown that, after 5 pulses of HCPEB treatment, maximum hardness in the surface layer of the sample was increased by 35% and the corrosion rate in 3.5 wt% NaCl water solution was reduced by 30% as compared with those of the untreated sample. The formation of nano structured cells of Mg-RE solid solution and β-Mg 5 (Gd,Y) nano precipitates, together with the residual compressive stress in the surface layer of the 5 pulsed sample account for the increased microhardness and improved corrosion resistance of the HCPEB treated Mg-8Gd-3Y-0.5Zr Mg alloy. Highlights • Mg 5 (Gd,Y) precipitates in the Mg-8Gd-3Y-0.5Zr alloy were dissolved into matrix after HCPEB treatment. • Hardness is increased in the HCPEB treated surface layers due to the formation of nanostructures and residual stresses. • Increased Gd/Y content and residual compressive stress in the 5 pulsed sample account for the improved corrosion resistance. [ABSTRACT FROM AUTHOR]

Abstract: MgZnO films with different Mg contents were synthesized on c-plane sapphire by metal organic chemical vapor deposition, using diethyl zinc (DEZn) and bis(cyclopentadienyl) magnesium (Cp2Mg) as Zn and Mg precursors, respectively. Tertiary butanol (t-BuOH) was used as a weak oxidant in order to enhance the accuracy of Mg incorporation when varying DEZn/Cp2Mg flow rates. As a result the Mg contents in the range of 1–9% were confirmed by time-of-flight elastic recoil detection analysis, which is known to be specifically sensitive to detect light elements. Thus, independently and accurately determined composition in the samples was correlated with structural and optical properties as measured by x-ray diffraction and photoluminescence. [Copyright &y& Elsevier]

Abstract: Single-crystalline ZnO film with two-dimensional periodic structure was grown on Si(111) substrate by radio-frequency plasma-assisted molecular beam epitaxy. The influence of substrate orientations and growth temperatures was explored for achieving a high-quality ZnO film. It was found that ZnO epilayers grown on Si(111) substrate have better crystalline quality than the one on Si(100), and a higher growth temperature was further confirmed favorable for the attainment of a periodic morphology. The results suggest that our growth method is feasible for the fabrication of ZnO film with periodic structure, which is promising for applications in new photonic devices. [Copyright &y& Elsevier]

Abstract: Cubic boron nitride (c-BN) crystals were synthesized in conditions of high temperature and high pressure (HTHP) when different kinds of bonded water were respectively added into the system of h-BN–Mg. All bonded water used in this work could reduce the temperature of growing c-BN compared to that in the system of h-BN–Mg. The c-BN color could change from black to yellow when certain amounts of bonded water, such as NiSO4·6H2O and CuSO4·5H2O, Mg(OH)2, were added. However, c-BN color remained black no matter how much bonded water, such as NiCl2·6H2O, CuCl2·2H2O, and SnCl2·2H2O, was added. The bonded water can be classified into Chlorine-containing bonded water (Cl-BW) and Chlorine-free bonded water (ClF-BW) according to their different characters and effects on the synthesized c-BN color. [Copyright &y& Elsevier]

Near-equiatomic TiNi alloy exhibits excellent wear resistance, benefiting from its pseudoelasticity and other intrinsic mechanical properties. The pseudoelasticity helps to reduce plastic deformation and absorb impact energy, thus decreasing the material loss. Since the martensitic transformation is temperature dependent, research was conducted to investigate the performance of Ti–51at.%Ni alloy during erosion as a function of temperature and the erodent velocity. The erosion behavior of the TiNi alloy was evaluated using a high-temperature air-jet erosion tester. The worn surface was examined using scanning electron microscopy and the transformation temperature was determined using differential scanning calorimetry (DSC). It was demonstrated that there was a minimum erosion loss with respect to temperature and the velocity of erodent also influenced this minimum erosion loss. Possible mechanism responsible for the erosion behavior of TiNi alloy is discussed. [Copyright &y& Elsevier]

Abstract: A route for realizing non-polar ZnO (112̄0) films with atomically smooth surface is demonstrated by employing rf-plasma assisted molecular beam epitaxy on ZnO bulk substrates. It is found that high growth temperature plays an important role in suppressing the typical striped structure along ZnO [0001] direction on non-polar planes. An atomically smooth surface with a root mean square roughness of 0.51nm that is suitable for fabrication of quantum wells is achieved after solving the growth anisotropy problem, as confirmed by the combined studies of reflection high-energy electron diffraction and atomic force microscopy. [Copyright &y& Elsevier]

Abstract: A route for synthesizing high Mg content single-phase wurtzite MgZnO films having band gaps in the solar-blind region is demonstrated by employing molecular beam epitaxy on Al2O3 substrates. Importantly, a low Mg content “quasi-homo” buffer, Mg0.17Zn0.83O, was applied to accommodate a host of structural discrepancies and therefore, avoiding phase separation in a high Mg content film, Mg0.55Zn0.45O, as proved by X-ray diffraction. The Mg fraction in the overgrown single-phase epilayer, Mg0.55Zn0.45O, was confirmed by Rutherford backscattering spectrometry. [Copyright &y& Elsevier]

ZnO/diamond hetero-junction diodes have been fabricated for the first time. The structure of the diode was n-type ZnO film/p-type diamond film on the {111} surface of a crystalline diamond. The contact between the n- and p-type semiconductors was found to be improved. The ratio of forward current to the reverse current exceeded 120 within the range of applied voltages of −4 to +4 V. The diode possessed an optical transmission of 50–70% in 500–700 nm wavelength regions. [Copyright &y& Elsevier]

Low-threshold heterojunctions have been formed from a boron-doped p-type diamond layer grown epitaxially on the {1 1 1} surface of a Si-treated single crystalline cubic boron nitride. The resistivity of the Si-treated cubic boron nitride was 0.1 Ω cm. With the resistivity of 0.1 Ω cm, which is lower than that of the sample prepared by conventional high-temperature and high-pressure method, the turn-on voltage and the highest current of the heterojunction are 0.5 V and 1 mA, respectively. [Copyright &y& Elsevier]

The growing behavior of cubic boron nitride (cBN) crystal in the system of hBN–Mg with bonded water (&z.dbnd6;(HO)2&z.dbnd6;) was investigated at 5.0 GPa and 1100–1500 °C. The results show that, with the existence of bonded water, the grown cBN crystals can appear different color and the growth temperature decreases approximately 300 °C with the pressure fixed at 5.0 GPa by contrast with that in the hBN–Mg system. In addition, the cBN synthesis process is quite different from that when bonded water is absent or that when magnesium is absent. [Copyright &y& Elsevier]

In the present work, the microstructure modifications and corrosion behaviors of a Mg-4Sm alloy treated by high current pulsed electron beam (HCPEB) with different number of pulses were investigated. The microstructure, composition and phase component in the treated surface layers were characterized by using optical microscope (OM), X-ray diffraction (XRD), scanning electron microscope (SEM) equipped with energy dispersive spectrometer (EDS) and transmission electron microscope (TEM). The results showed the dissolution of large Mg 41 Sm 5 segregates, the formation of Mg 41 Sm 5 nano-precipitates and twins in the surface layers after treatments. Electrical impedance spectroscopy (EIS) and polarization tests in the 3.5 wt% NaCl solution showed that the 15 pulses treated Mg-4Sm alloy sample exhibited the lowest corrosion current density, highest corrosion potential and polarization resistance among all samples. This is attributed to the homogeneous microstructure and composition with fewer defects in the surface layer after sufficient number of HCPEB pulses. [ABSTRACT FROM AUTHOR]

Pharmaceutically active compounds (PhACs), which find their way easily into the water sources, are emerging as a major concern for drinking water quality and aquatic species. Therefore, their removal from water sources is a priority from environmental point of view. During the past decade, different methods including membrane separation, adsorption systems and chemical transformation have been evaluated for removal of these compounds. This paper reviews different aspects of PhAC removal by using membrane separation processes, as they have been conventionally known to show high potential in the production of superior quality drinking and industrial water. In brief, osmosis membranes can efficiently remove almost all PhACs though its operational cost is relatively high and nanofiltration (NF) membranes are highly influenced by electrostatic and hydrophobic interaction. Moreover, the efficiency of membrane bioreactors (MBRs) is difficult to predict due to the complex interaction of compounds with microorganisms. To improve the performance and robustness of membrane technology, it is suggested to combine membranes with other systems, such as activated carbon and enzymatic degradation. [ABSTRACT FROM AUTHOR]

Asserts the need for China to preserve its biodiversity. Factors affecting the country's biodiversity; Scientific basis of biodiversity research; Importance of conservation biology; Proposal for the establishment of a national centre for ecology and evolution.

The effect of post-weld heat treatment processing parameters on the microstructure, fracture morphology, fracture toughness and crack propagation direction of the linear friction welded joint for dissimilar titanium alloys was investigated. Results show that weld zone and one side of thermo-mechanically affected zone are weak zones for fracture toughness of linear friction welded joint for dissimilar titanium alloys after welding; post-weld heat treatment can effectively improve the fracture toughness of the weak zones, but has less effect on that of the other side. During the heat treatment process, the fine acicular and equiaxed microstructures in the weak weld zones grow and partly transform into lamellar microstructure which can increase the total length of the crack along with energy consumption and relieve the residual stress, resulting in enhancing the fracture toughness of the joint. Meanwhile, the fracture morphology gradually transforms from intergranular fracture to ductile–brittle mixed fracture and dimple fracture. [ABSTRACT FROM AUTHOR]