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MXene-TiO2 mesoporous membranes on α-Al2O3 hollow fiber supports are prepared and regulated by adjusting the two-dimensional (2D) MXene content. The prepared MXene-TiO2 membranes are characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and x-ray diffraction. The results show that TiO2 nanoparticles (NPs) are uniformed deposited on 2D platforms and that the 2D structure of the original MXenes is still preserved in the film after calcination, thereby successfully inhibiting sol infiltration into the porous support. The obtained MXene-TiO2 layer with a controllable thickness exhibits ‘ideal’ pathways (longitudinal-lateral transport nanochannel) for dextran molecules between the TiO2 NPs and MXene nanosheets. Furthermore, the MXene-TiO2 membranes show higher rejection performance of dextran with increasing 2D MXene content. The optimal mesoporous MXene-TiO2 hollow fiber membranes exhibit a cut-off molecular weight (MWCO) of 14 854 Da and a high pure water flux of 102 l m−2 h−1 per bar, thereby showing good potential as high-performance interlayers for ceramic nanofiltration membranes.

A simple and scalable method was proposed for the preparation of the mesoporous membranes by assembling 2D MXene nanosheets and TiO2 nanoparticles (NPs) on a macroporous support. MXene nanosheets were introduced into TiO2 hydrosol, and then transformed the gel for fabrication of mesoporous TiO2@MXene membranes. Characterization results confirmed that an assembled structure of TiO2@MXene nanosheets was formed, benefiting from the nanosheets as 'floor tiles', thereby successfully inhibiting the sol infiltration into the porous support. As a result, the hydrosols could be directly coated on macroporous substrates including a disc support with an average pore size of ~100 nm and a four-channel hollow fiber with an average pore size of ~300 nm. It should be emphasized that the integrated disc or hollow fiber TiO2@MXene membranes were fabricated by only one single cycle of coating, aging and calcination. A range of advanced membrane characterization techniques were employed to study the ultrastructure of the fabricated membranes and the assumption of introducing nanosheets to prevent membrane defect and gel infiltration was validated.Filtration experiments revealed the resulted membranes, in particular the hollow fiber TiO2@MXene membranes, had a narrow pore size distribution, desirable rejection chacteristics and high permeate flux. The 2D nanosheet assisted TiO2 NPs assembly proposed in this work promises a simple, feasible and scalable approach for fabrication of high-performance mesoporous TiO2 membranes.

A thinner Y-TZP specimen was likely to present surface defects and microcracks after aging. In addition, the flexural strengths decreased with a decrease in the thickness, a notable fact for further studies.

Objective: To explore the correlation between ischiocavernosus muscle injury (ICMI) with different types of pelvic fractures and erectile dysfunction (ED) after pelvic fracture. Design: Retrospective analysis of a prospective database. Setting: The study was carried out at the affiliated hospital of Zunyi Medical University. Patients/participants: A total of 776 male patients with pelvic fracture, aged 18 to 67 years, were recruited for this study by retrospective analysis, and based on the diagnosis of ED and the presence of ICMI, the participants were divided into ED and non-ED groups as well as ICMI and non-ICMI groups. Intervention: No. Main outcome measurements: ICMI, the type of pelvic fracture, International Index of Erectile Function-5 scores. Computed tomography/magnetic resonance imaging scans, electromyography (motor unit potential) was used to diagnose ICMI. Results: The International Index of Erectile Function-5 score was 19.7 ± 5.9. The incidence of ED was 27.3%, the duration time of ED was 30 ± 23 months, and the incidence of reversible ED was 39.6% and of irreversible ED was 60.4%. The incidence of ICMI was 29.4%, among which the incidence of unilateral injury was 57.9%, and the incidence of bilateral injury was 42.1%. Among all pelvic fractures, the incidence of pubic ramus fracture was 88.1%. Bilateral pubic ramus fractures, bilateral fractures of the ischial ramus, and ICMI were independent risk factors for ED after pelvic fracture. Bilateral pubic ramus fractures and pubic symphysis separation were independent risk factors for ICMI. Unilateral ICMI was an independent risk factor for reversible ED, while bilateral ICMI was an independent risk factor for irreversible ED. Conclusions: ICMI is associated with ED and may be a cause for ED, while pubic ramus fracture, ischial ramus fracture, and pubic symphysis separation may be the main causes of ICMI. Unilateral ICMI may be the main risk factor for transient ED, and bilateral ICMI may be the main risk factor for permanent ED.

Illustration of reaction mechanism of the EF process.

The origin of ferroelectricity and antiferroelectricity in zirconia (ZrO2) ultrathin films has become a topic of great interest in recent years. The normal ferroelectricity in ZrO2 is widely considered to originate from the high-pressure noncentrosymmetric Pca21 orthorhombic (o) phase. While the antiferroelectric-like behavior is regarded as the result of a phase transition from the centrosymmetric and paraelectric P42/nmc tetragonal (t) phase to the ferroelectric o-phase under electrical loading. This study reports an effective technique to selectively produce a ferroelectric or antiferroelectric ZrO2 ultrathin film (∼15 nm) without compositional manipulation. The technique is based on tailoring the crystal orientation of the Pt bottom electrode on which the ZrO2 ultrathin film is deposited. By correlating the results of the XRD, HRTEM, and electric field-polarization (P-E) analyses, it is found that a cubic phase (111)-oriented Pt electrode promotes the textured growth of the ferroelectric o-phase (111) planes in the ZrO2 ultrathin film; while a random-oriented Pt electrode leads to a t-phase dominated system, resulting in an antiferroelectric-like pinched P-E hysteresis. The modulation of ZrO2 ferroelectricity via the crystal orientation of the Pt bottom electrode can be achieved with a low thermal budget (< 400 °C), making it highly favorable for process integration and device scaling in a variety of nanoelectronics and nanoelectromechanical applications.