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TiO 2 is exceptionally useful anode material for Li-ion batteries, and the ability to modify TiO 2 makes it a very attractive and challenging research object for use in different functional materials. In this paper, mesoporous TiO 2 nano hollow spheres (dubbed TiO 2 -1 andTiO 2 -2) with moderate oxygen vacancies were successfully prepared. Structure and composition characterizations revealed that the spheres had a hollow structure, surface oxygen vacancies and an excellent Ti3+/Ti4+ molar ratio of 0.181. In addition, TiO 2 -2 demonstrated synergistic effects in terms of electron and lithium ion transportation, with impedances as low as 3.05 Ω, and its Li-ion diffusion coefficient (7.8 × 10−12 cm2 s−1) was at least a factor of 10 larger than that of TiO 2 -1(6.2 × 10−13 cm2 s−1). More importantly, experiments demonstrated that the well-balanced Li+/e− transportation arising from the synergetic effect between structure and Ti3+/oxygen vacancy in the optimal TiO 2 -2 sample had a high specific capacity of 233 mAh·g−1 at 0.1C, and 79.8% capacity retention after 100 cycles, as well as greatly enhanced rate performance and electrochemical reactivity and stability in comparison with the other TiO 2. Our method for creating oxygen vacancies in TiO 2 nano hollow spheres can be generalized to other electrochemical energy storage materials. [ABSTRACT FROM AUTHOR]

• The hydration of glass is heterogeneous due to phase-separation structure; • The heterogeneous hydration of glass impact the formation of calcium hydroxide; • The hydration rate advantage of calcium-rich and silicon-rich phase can be reversed; • The heterogeneous hydration is suitable for thermodynamic simulation of cement paste; Supplementary cementitious materials (SCMs) affect the hydration process and long-term properties of cementitious systems. Since a large percentage of SCMs belong to alkaline-earth aluminosilicate glasses that possess a phase-separated structure, further research into their hydration characteristics is essential. This study investigated the effects of the hydration characteristics of synthetic glasses with various phase-separated structure on the phase evolution of cementitious systems by combining simulations with experiments. The results showed that with the increasing degree of phase separation, the hydration of synthetic glass transitions from homogeneous to heterogeneous hydration. The phase evolution of hardened paste, particularly for calcium hydroxide, is influenced by the difference in hydration rates among each separated glassy phase. Compared to homogeneous hydration, the rapid hydration of the Ca-rich phase reduced the consumption of calcium hydroxide, while the rapid hydration of the Si-rich phase accelerated calcium hydroxide consumption. For glasses exhibiting phase separation characteristics, the consistency between thermodynamic simulations employing a heterogeneous hydration model and experimental results exhibits a notable enhancement. [ABSTRACT FROM AUTHOR]

The effective recovery of metallic iron and vanadium from steel slag and ensuring the gelling properties of the residual slag after metal separation are crucial for their high-value-added utilisation. In this study, we established suitable process conditions for high-temperature reduction and reconstruction using the Si/Al ratio as an adjustment parameter and employing rice husk ash, SiO 2 , and Al 2 O 3 as the adjustment materials. The influence of the reconstructed steel slag composition and structure on the iron reduction rate and vanadium migration was investigated. Additionally, we tested the compressive strength of the cement slurry at different times to compare the gelling performance of the tailings after iron reduction from the Vanadium-containing steel slag.The results showed that the high-temperature reduction method effectively reduced metallic iron and vanadium in the steel slag. The iron reduction rate reached as high as 98.53%, and inert components such as the CaO-FeO-MgO-MnO solid solution (RO) phase, C 2 F, and Fe 3 O 4 in the original steel slag could be effectively reconstructed to form a glass-phase structure with certain gelling properties. Moreover, the content of the glass phase remained stable above 90%. For the same temperature, the liquid viscosity of the reconstructed steel slag increased, and after cooling, the glass-phase content decreased with decreasing Si/Al ratio. This resulted in an increase in the amount of crystalline-phase minerals such as Ca 3 Mg(SiO 4) 2 , Ca 2 Al 2 SiO 7 , and C 2 S. The iron reduction rate generally exhibited a downward trend, and the change in the vanadium content was consistent with the iron reduction rate. Following the reduction and reconstruction of iron separation, the gelling properties of the vanadium-containing steel slag improved, with a 28-day strength that was 64.26% higher than that of the original steel slag. • Reconfiguration process was established using Si/Al ratio as a tuning parameter. • The reduction rate of iron was as high as 98.53%. The glass-phase content could be stabilised above 90%. • The highest vanadium reduction rate was 60.6%. • After the reduction and reconstruction of iron separation, the gelling property of the steel slag with vanadium improved. [ABSTRACT FROM AUTHOR]

Abstract The modification of TiO 2 is a vigorous and challenging research field. In the present study, TiO 2 /CuO composite nanofibers, designed by considering the thermodynamics of nanocrystals, have been synthesized by an electrospinning and hydrothermal method. The results showed that the grain growth of uniform and highly active CuO was driven by the surface drag force of TiO 2 nanofibers. TiO 2 /CuO showed an alternating current impedance as low as 2.874 Ω, and the Li+ diffusion rate was increased tenfold compared to that of bare TiO 2 nanofibers. Equally importantly, the electron diffusion kinetics was also explored, which revealed that the band gap was reduced by 1.14 eV compared to that for bare TiO 2 nanofibers. In addition, TiO 2 /CuO exhibited satisfactory stability and electrochemical performance. Its initial discharge capacity was 540 mAh·g−1, and that after discharge over 400 cycles at 0.1 C was 174 mAh·g−1. The design method may be more broadly applied to various nanostructured TiO 2 materials. [ABSTRACT FROM AUTHOR]

In this paper, a cooperative polynomial guidance problem is investigated against a maneuvering target based on trajectory parameterization with collision avoidance and flight path angle coordination. To this end, a polynomial reference trajectory satisfying the initial and terminal constraints is introduced with its highest-order coefficient chosen as the guidance gain. Then, a safe distance criterion is enforced to coordinate parameters of the missiles for collision avoidance along the reference trajectories. Finally, the cooperative guidance law is developed by ensuring a smooth tracking of the polynomial reference trajectory. Numerical simulations verified performance of the proposed guidance strategy. [ABSTRACT FROM AUTHOR]

This work described a novel labdisc platform adopting membrane-resistance (MembR) valves for fully automated sample-to-answer detection of highly pathogenic avian influenza viruses (HPAIVs). The MembR valves as the passive valves were successfully developed by utilizing different hydrophobic or hydrophilic polycarbonate membranes with superfine pore sizes and used in experiments. It allowed a large range of effective rotational speed for fluid control on the disc from 500 to 4750 rpm. In the platform, six MembR valves enabled effective pre-storage and manipulation of RNA extraction reagents under five different rotational speeds. With the help of MembR valves, all the processes for molecular diagnosis including sample lysis, RNA extraction and purification, and specific RNA detection using real-time reverse transcription loop-mediated isothermal amplification (RT-LAMP) were integrated on the single disc. We demonstrated that samples of three HPAIVs H7N3, H7N9, and H9N2 and two other influenza A subtypes H1N1 and H3N2 can be automatically analyzed on the centrifugal disc within 70 min. All experiments were applied in a 4 kg portable, laptop controlled point-of-care device. Furthermore, the platform provided a closed non-contact heating with accurate temperature control for POCT nucleic acid diagnosis. [ABSTRACT FROM AUTHOR]

Skin tissue is the first barrier against ambient harmful matter and has direct contact with indoor air pollutants. Nevertheless, a comprehensive understanding of cytotoxicity of indoor air pollution on skin cells is insufficiently clear. Herein, for the first time a multilayered dynamic cell culture platform was established to study the cytotoxicity of indoor air pollutant from biomass combustion in human skin keratinocytes. The platform consisted of seven repetitive polydimethylsiloxane modules carrying six pieces of polycarbonate membrane between them as substrate for cell growth to realize the simultaneous dynamic culture of 12 layers of keratinocytes. After exposure to biomass combustion soluble constituents (BCSCs), cell viability under microfluidic platform conditions declined more significantly, and apoptosis rates increased more obviously compared with well plate conditions. Transmission electron microscope showed that keratinocyte microstructures displayed obvious signs of cellular damage. Our study confirmed that the nuclear factor of kappa B (NF-κB) signaling pathway was activated, which significantly increased the Bax/Bcl-2 ratio and tumor necrosis factor-alpha and interleukin 6 expression, indicating that NF-κB signaling pathway was the major factor in BCSCs-induced cytotoxicity. These findings offer an insight into the mechanism of BCSCs-induced cytotoxicity in keratinocytes and provide a theoretical basis for future studies on skin cells. [ABSTRACT FROM AUTHOR]

SARS-Cov-2 has erupted across the globe, and confirmed cases of COVID-19 pose a high infection risk. Infected patients typically receive their treatment in specific isolation wards, where they are confined for at least 14 days. The virus may contaminate any surface of the room, especially frequently touched surfaces. Therefore, surface contamination in wards should be monitored for disease control and hygiene purposes. Herein, surface contamination in the ward was detected on-site using an RNA extraction-free rapid method. The whole detection process, from surface sample collection to readout of the detection results, was finished within 45 min. The nucleic acid extraction-free method requires minimal labor. More importantly, the tests were performed on-site and the results were obtained almost in real-time. The test confirmed that 31 patients contaminated seven individual sites. Among the sampled surfaces, the electrocardiogram fingertip presented a 72.7% positive rate, indicating that this surface is an important hygiene site. Meanwhile, the bedrails showed the highest correlation with other surfaces, so should be detected daily. Another surface with high contamination risk was the door handle in the bathroom. To our knowledge, we present the first on-site analysis of COVID-19 surface contamination in wards. The results and applied technique provide a potential further reference for disease control and hygiene suggestions. Unlabelled Image • First report about on-site detection of SARS-CoV-2 in wards • The whole detection process could accomplish within 45 min without nucleic acid extraction. • The presence of SARS-CoV-2 in wards was confirmed by nucleic acid isothermal amplification. [ABSTRACT FROM AUTHOR]