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Photocatalytic antimicrobial is a promising advanced oxidation antibacterial technology that can utilize solar energy to achieve antibacterial function. However, due to the influence of diurnal variation, photocatalytic antimicrobials cannot maintain a continuous antibacterial effect in practical applications. Herein, a TiO2 fiber with CuO particle (TiO2/CuO) pn-type heterojunction with dual inactivation of Escherichia coli has been designed and prepared for water treatment. The formation of pn heterojunction and its high efficiency of charge separation and transfer were confirmed through HRTEM, FESEM, UV–Vis and photoelectrochemical tests, while the charge separation process of the heterojunction under visible-light irradiation was systematically investigated. The results showed that the antimicrobial rate of TiO2/CuO composites was 64.7% at 10 min under dark conditions. In contrast, under light exposure, the antibacterial rate could reach 96.2% for 10 min and 100% for 20 min. This research holds promise for advancing the construction of pn heterojunctions and provides a novel insight into reducing the dependence of photocatalytic antimicrobials on light. [ABSTRACT FROM AUTHOR]

In this work, a TiO2/In2S3 heterojunction film was successfully synthesized using a one-step hydrothermal method and applied in the photocathodic protection (PCP) of 304SS. The octahedral In2S3 and In2S3@TiO2 nanoparticles combined and coexisted with each other, with In2S3 quantum dots growing on the surface of TiO2 to form In2S3@TiO2 with a wrapping structure. The composite photoelectrode, which includes TiO2 with a mixed crystalline phase and In2S3, exhibited significantly enhanced PCP performance for 304SS compared with pure In2S3 and TiO2. The In2S3@TiO2/In2S3 composites with 0.3 g of P25 titanium dioxide (P25) showed the best protection performance, resulting in a cathodic shift of its OCP coupled with 304SS to −0.664 VAgCl. The electron transfer tracking results demonstrate that In2S3@TiO2/In2S3 forms a Z-scheme heterojunction structure. The enhanced PCP performance could be attributed to the synergistic effect of the mixed crystalline phase and the Z-scheme heterojunction system. The mixed crystalline phase of TiO2 provides more electrons, and these electrons are gathered at higher energy potentials in the Z-scheme system. Additionally, the built-in electric field further promotes the more effective electrons transfer from photoelectrode to the protected metals, thus, leading to enhanced photoelectrochemical cathodic protection of 304SS. [ABSTRACT FROM AUTHOR]

In this work, an oxidized g-C3N4 film was successfully synthesized using a two-step acid treatment and electrophoretic deposition method. The delocalized π-system of the oxidized g-C3N4 film was extended via an annealing treatment. We investigated the influence of hydrogen bonding reversibility and the oxidation treatment of g-C3N4 on the photoelectrochemical property and photocathodic protection for 304 stainless steel (304 SS). The resulting oxidized g-C3N4 photoelectrode with an extended π-system presents a remarkably enhanced photogenerated electron transfer capability from the photoelectrode to 304 SS (photoinduced OCP negative shift of −0.55 VAgCl) compared with oxidized g-C3N4 and protonated g-C3N4. The oxidation of g-C3N4 facilitates the formation of a porous structure and the introduction of abundant oxygen functional groups, which could promote the effective separation and transport of photogenerated electron–hole pairs. The hydrogen bonding reversibility contributes to the extension of the delocalized π-conjugation system, which could enhance light absorption efficiency. Meanwhile, the annealing treatment is beneficial for prolonging the lifetime of photoelectrons, which could reduce the recombination rate of charge carriers. In addition, to understand how the oxidation treatment and annealing treatment affect the charge transfer behavior, the electronic band structure was investigated, and we found that the oxidized g-C3N4 film with an extended π-system possesses a more negative conduction band position, which could reduce the energy barrier of the photogenerated electron transfer. [ABSTRACT FROM AUTHOR]

Mesoporous carbon nanotubes (mCNTs) hold great promise interests, owing to their superior nano-platform properties for biomedicine. To fully utilize this potential, the toxicity and biodistribution of pristine and surface-modified mCNTs (-OH/-COOH) should preferentially be addressed. The results of cell viability suggested that pristine mCNTs induced cell death in a concentration-dependent manner. As evidence of reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD), pristine mCNTs induced noticeable redox imbalance. 99mTc tracing data suggested that the cellular uptake of pristine mCNTs posed a concentrate-dependent and energy-dependent manner via macropinocytotic and clathrin-dependent pathways, and the main accumulated organs were lung, liver and spleen. With OH modification, the ROS generation, MDA deposition and SOD consumption were evidently reduced compared with the pristine mCNTs at 24/48 h high-dose exposure. With COOH modification, the modified mCNTs only showed a significant difference in SOD consumption at 24/48 h exposure, but there was no significant difference in the measurement of ROS and MDA. The internalization mechanism and organ distribution of modified mCNTs were basically invariant. Together, our study provides evidence that mCNTs and the modified mCNTs all could induce oxidative damage and thereby impair cells. 99mTc-mCNTs can effectively trace the distribution of nanotubes in vivo. [ABSTRACT FROM AUTHOR]

In order to solve the existing problems such as non-standard size, easy deformation and inconvenient movement of the arm of dress form, a movable arm of male dress form was designed and manufactured by using forward and reverse hybrid modeling technology and rapid prototyping technology. According to the point cloud data of human arm obtained by 3D scanner, the arm model was reconstructed by Geomagic and ZBrush software. The shoulder joint connectors were designed by Solidworks software. Then the arm model engraving, joint model printing and connection piece laser cutting were realized by rapid prototyping technology. Finally, the self-made arm of dress form was compared and analyzed with the existing products in the market. The result shows that the self-made arm of dress form not only ensures the accuracy of the size, but also can simulate the basic movements of the human arm swinging back and forth and lifting up and down, which meets the requirements of mobility in sleeve design and provides technical reference for mannequin manufacturing enterprises. [ABSTRACT FROM AUTHOR]