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Belite sulfoaluminate cement is attracting increasing attention and being considered as a potential alternative to ordinary Portland cement owing to lower preparation temperature and carbon dioxide (CO2) emission. However, it still has disadvantages of poor workability and low early strength. This study investigated the effects of compound polycarboxylate superplasticiser (PCE) and early strength agent, calcium nitrite (Ca(NO2)2), on flowability and early strength of belite calcium sulfoaluminate (BCSA) cement. Variation patterns of setting time, fluidity, strength and polycarboxylate superplasticiser (PCE) adsorption of the paste were measured; the hydration products and microscopic morphology were also analysed by the heat of hydration, X-ray diffraction and scanning electron microscopy. Results showed that calcium nitrite effectively enhanced adsorption of PCE onto the surface of BCSA cement particles, leading to notable improvement in the fluidity of the paste (reaching up to 275 mm). In the initial hydration stage, 0.7% PCE compounded with 1.2% calcium nitrite inhibited the formation of ettringite (AFt), resulting in prolonged setting time. However, it deepened the degree of hydration of BCSA for 3 days and refined the hydration product, AFt crystals. Consequently, the compressive strength was increased to 95.75 MPa and 107.13 MPa for BCSA cement at 3 days and 28 days, respectively. [ABSTRACT FROM AUTHOR]

Dexmedetomidine has been demonstrated to be effective in the management of pain in total knee replacement (TKA). Nevertheless, a combination of a local anaesthetic and a dose of dexmedetomidine might be a better choice for post‐operative pain management of TKA. The aim of this research is to determine if the combination of a local anaesthetic with dexmedetomidine during a knee replacement operation can decrease the post‐operation pain. Furthermore, the effectiveness and security of dexmedetomidine combined with topical anaesthetic were evaluated for the management of post‐operative TKA. Based on the research results, the author made a research on the basis of four big databases. The Cochrane Handbook on Intervention Systems Evaluation has also evaluated the quality of the literature. Seven randomized controlled trials have been established from this. It was found that the combination of local anaesthesia and dexmedetomidine had a greater effect on postoperative pain in 4 h (mean difference [MD], −0.9; 95% CI, −1.71, −0.09; p = 0.03), 8 h (MD, −0.52; 95% CI, −0.66, −0.38; p < 0.0001), 12 h (MD, −0.72; 95% CI, −1.04, −0.40; p < 0.0001), 24 h (MD, −0.49; 95% CI, −0.83, −0.14; p = 0.006), 48 h (MD, −0.51; 95% CI, −0.92, −0.11; p = 0.01). Nevertheless, because of the limited number of randomized controlled trials covered by this meta‐analysis, caution should be exercised with regard to data treatment. More high quality research will be required to confirm the results. [ABSTRACT FROM AUTHOR]

Distal tibial fracture is the most commonly seen type of fracture of the lower extremities. Both intramedullary nail fixation (INF) and plate fixation (PF) have been used to treat distal tibial fractures, but the best way to treat them is still in dispute. The purpose of this meta‐analysis is to compare INF versus PF fixation with respect to the incidence of injury. For studies that have been published between inception and June 2023, a systematic review has been carried out on PubMed, Embase, Cochrane Library and Web of Scientific databases. All of the trials that looked at INF and PF‐related complications were enrolled. Data from the 13 primary results were analysed with RevMan 5.3. The meta‐analyses comprised 13 randomized controlled trials (RCTs). INF indicates that there is a tendency for patients with distal tibia fractures to reduce the risk of operative site infection (odds ratio [OR], 2.09; 95% confidence interval [CI], 1.40, 3.13; p = 0.0003) after surgery compared with PF. INF resulted in a reduction in total wound complications (OR, 14.20; 95% CI, 1.81, 111.57; p = 0.01) but shortened operation time (mean difference, 13.03; 95% CI, 2.08, 23.99; p = 0.02). In view of these findings, INF seems to be a preferred method of surgery for the treatment of distal tibial fractures with respect to the reduction of post‐operative wound complications. [ABSTRACT FROM AUTHOR]

A novel PSAC@[Fe.sub.3][O.sub.4]/Ag composite, with high efficiency in the degradation of Rhodamine B, was synthesized through a simple wet-chemistry method. The results showed that the rate of the catalytic reaction was significantly concentration-dependent. Furthermore, there was no significant loss in the catalytic activity of the recycled catalysts, even after being recycled nine times (average 83%), from which one can deduce that almost all the nanosilver were regathered due to the super-paramagnetic [Fe.sub.3][O.sub.4] nanoparticles. Key words: recyclable catalysts, magnetite, silver, rhodamine B. Faisant appel a une methode simple de chimie humide, on a synthetise un nouveau composite PDAL@[Fe.sub.3][O.sub.4] /Ag tres efficace pour la degradation de la Rhodamine B. Les resultats montrent que la vitesse de la reaction catalytique depend fortement de la concentration. De plus, il n'y a pas de perte significative de l'activite des catalyseurs recycles, meme apres neuf recyclages (moyenne de 83%); ces resultats permettent de deduire que pratiquement tout le nanoargent est recupere en raison des nanoparticules de [Fe.sub.3][O.sub.4] superparamagnetiques. Mots-cles : catalyseurs recyclables, magnetite, argent, rhodamine B. [Traduit par la Redaction], Introduction Recently, metal nanoparticles have become a hotspot in various fields, (1-3) not only because of their particular properties, (4,5) which are obviously different from their bulk materials, but also [...]

The development of pure deep-blue emitters with excellent optoelectronic and electroluminescence (EL) properties is full of challenges due to limited molecular designs. Herein, three novel color-tunable phenylcarbazole derivative based emitters from deep-blue to blue pCz-DPS, pCz-BTO and pCz-BP were demonstrated, which were designed by incorporating different short conjugation length building blocks as electron-accepting moieties and twisted rigid electron-donating carbazole derivatives. These emitters show deep-blue to blue emission, thanks to the deep highest occupied molecular energy level of the carbazole derivative donor units. In addition, pCz-BP exhibits aggregation-induced emission (AIE) properties, while pCz-BTO exhibits AIE and thermally activated delayed fluorescence (TADF) properties simultaneously. Nondoped organic light-emitting diodes (OLEDs) using these emitters as emission layers were fabricated, along with a maximum external quantum efficiency (EQE) and Commission Internationale de l'Éclairage (CIE) color coordinates of 7.1% and (0.15, 0.10) for pCz-BTO devices. The pCz-BTO emitter can also function robustly in doped OLEDs with an impressive maximum current efficiency (CE) and EQE of 23.3 cd A−1 and 9.5%, respectively, along with ultrapure blue color CIE coordinates of (0.15, 0.09). The significantly excellent performance of pCz-BTO could be ascribed to excellent photoluminescence quantum yield (PLQY), high reverse intersystem crossing rate constant (kRISC) and high fluorescence decay rate constant (kF) values. The excellent performance, ultrahigh color purity and extremely low efficiency roll-off of pCz-BTO are among the state-of-the-art deep-blue emitters, indicating the great potential of these materials in the application of ultrapure deep-blue OLEDs. [ABSTRACT FROM AUTHOR]

One-step forming TiCp/Ni3Al-Ni3Al multi-coating on powder metallurgy 316L stainless steel substrate was fabricated by vacuum hot-pressing sintering technology and its wear performances at different loads and ambient temperatures were investigated. The wear weight loss of TiCp/Ni3Al-Ni3Al multi-coating increased with the increase in the applied load and a mild-to-severe wear transition occurred. Inversely, the coating's wear weight loss decreased as the ambient temperature increased. The high wear resistance at elevated temperatures was mainly attributed to high work-hardening capacity and high temperature strength of Ni3Al matrix. Besides, the mechanically mixed layer with dispersed TiC particulates prevented the substrate from plastic deformation and thermal softening, which were conducive to improve the wear resistance of the coating. [ABSTRACT FROM AUTHOR]

Hg2+ is a serious environmental contaminant that can cause severe damage to the immune and nervous systems, and Hg2+ monitoring is critical. Herein, we report a novel, simple, and sensitive Hg2+ sensor based on the enhanced peroxidase‐like activity of chitosan–gold nanoparticles (CS‐AuNPs). The peroxidase‐like activity of the CS‐AuNPs can be markedly enhanced by Hg2+ as seen by the deeper color and increased absorbance at 652 nm. This improved catalytic ability was used to develop a sensitive and selective colorimetric sensor for Hg2+ detection. The limit of detection via the absorption spectra is as low as 0.02 μM. The mechanism underlying the enhanced catalytic ability is discussed. This approach is label‐free, simple, and offers detection with the naked eye. Thus, it has potential applications for the detection of Hg2+ in environmental and food samples. [ABSTRACT FROM AUTHOR]