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An SiO2–TiO2 closed-surface antireflective coating was fabricated by the one-dipping method. TiO2 nanoparticles were mixed with a nanocomposited silica sol, which was composed of acid-catalyzed nanosilica networks and silica hollow nanospheres (HNs). The microstructure of the sol–gel was characterized by transmission electron microscopy. The silica HNs were approximately 40–50 nm in diameter with a shell thickness of approximately 8–10 nm. The branched-chain structure resulting from acidic hydrolysis grew on these silica HNs, and TiO2 was distributed inside this network. The surface morphology of the coating was measured by field emission scanning electron microscopy and atomic force microscopy. After optimization, transmittance of up to 94.03% was obtained on photovoltaic (PV) glass with a single side coated by this antireflective coating, whose refractive index was around 1.30. The short-circuit current gain of PV module was around 2.14–2.32%, as shown by the current–voltage (IV) curve measurements and external quantum efficiency (EQE) tests. This thin film also exhibited high photocatalytic activity. Due to the lack of voids on its surface, the antireflective coating in this study possessed excellent long-term reliability and robustness in both high-moisture and high-temperature environments. Combined with its self-cleaning function, this antireflective coating has great potential to be implemented in windows and photovoltaic modules.

Phase equilibrium of the Fe-Si-Sn ternary system was investigated using equilibrated alloys. The samples were characterized by means of scanning electron microscopy equipped with energy dispersive X-ray spectrometry and X-ray diffraction. Isothermal sections of the Fe-Si-Sn system at 700 o C and 890 o C each consists of 5 three-phase regions. No ternary compound was found at those two temperatures. The solubility of Sn in the Fe-Si binary phases and the solubility of Si in the Fe-Sn binary phases is limited. Furthermore, thermodynamic extrapolation of the Fe-Si-Sn system was carried out. Calculated solidification path and phase relationship agreed well with experimental results.

In this study, we investigated the microstructure, mechanical properties, and thermal performance of Sn-xBi-1Ag (x = 35, 37, 45, and 47 wt.%) solders, with a particular focus on the effect of adding trace Si atoms. The impact of different Ag concentrations on the properties of Sn-xBi-Ag-0.5Si solders was also studied. The results indicated that as the amount of Bi added to Sn-xBi-1Ag solder alloys increased, the tensile strength, microhardness, melting temperature, and melting range decreased somewhat, but the wettability improved. The Cu6Sn5 layer between the soldering alloy and the Cu substrate became thinner upon increasing the Bi content. Adding microcrystalline Si atoms to the Sn-Bi-1Ag alloy improved the tensile strength and microhardness, but the melting point and melting range were not significantly changed. The wettability was optimized, and the diffusion layer formed with the Cu matrix was significantly thinner. By increasing the Ag content in the Sn-Bi-(1,3)Ag-0.5Si alloy, the tensile strength of the alloy was continuously strengthened, while the hardness decreased slightly and the melting point and melting range increased slightly. The wettability was greatly improved, and the Cu6Sn5 layer became thinner.

Objective:The number of people infected with human immunodeficiency virus (HIV) in China has increased in recent years. HIV screening for pregnant women was performed in a remote area in Xinjiang, as an effort to promote universal HIV screening in pregnant women and to help prevention of mother-to-child transmission.Methods:Pregnant women in Burqin and Jeminay Counties in Xinjiang were offered free voluntary HIV screening. Local mid-level medical workers were trained to use Determine® HIV-1/2 kit for HIV screening. All the tested pregnant women signed a consent form, received HIV education material, and participated in an HIV knowledge survey.Results:All the 890 pregnant women receiving HIV test had negative result. Among these women, 67.6% were Kazakh and 40.9% were farmers. Survey of HIV knowledge showed that these women's awareness about mother-to-child transmission was limited. The levels of HIV knowledge were related with ethnic background, age, education and profession of the pregnant women.Conclusion:The results suggested that HIV infection had not become a significant problem among the pregnant women in this remote area of Xinjiang, but continued efforts to improve the awareness of HIV, especially the knowledge about mother-to-child transmission of HIV, in pregnant women were needed.