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Non-precious metal catalysts with enhanced low-temperature activity and improved water resistance are highly demanded for emission control. CuO-based catalysts are promising alternatives to precious metal catalysts due to their acceptable activity and cost-effectiveness. However, there is an urgent need to further enhance their low-temperature activity and water resistance for industrial applications. Herein, CuO catalysts supported by various SiO2-TiO2 supports were prepared and evaluated for CO oxidation and NO reduction by CO reactions under the testing conditions with and without water. Among the studied catalysts with different SiO2 contents, CuO/5SiO2-TiO2, in which CuO was supported by SiO2-TiO2 with 5 wt.% SiO2, exhibited the best performance for CO oxidation. Compared with CuO/TiO2 and CuO/SiO2 reference catalysts, the CuO/5SiO2-TiO2 catalyst showed enhanced catalytic activity in both CO oxidation and NO reduction by CO under dry and wet conditions. Comprehensive characterizations revealed that the presence of SiO2 in TiO2 support facilitated the CuO/5SiO2-TiO2 catalyst with a high dispersion and reduced oxidation states of CuOx species. This not only improved the low-temperature reducibility but also enhanced the adsorption of reactive CO species. As a result, the CuO/5SiO2-TiO2 catalyst demonstrated superior catalytic activity. Furthermore, the inclusion of SiO2 in the catalyst inhibited H2O adsorption, contributing to the enhanced water resistance on CuO/5SiO2-TiO2 catalyst. These advantages in catalytic activity and water resistance make CuO/5SiO2-TiO2 a promising candidate for applications in emission control. [ABSTRACT FROM AUTHOR]

Non-precious metal catalysts with enhanced low-temperature activity and improved water resistance are highly demanded for emission control. CuO-based catalysts are promising alternatives to precious metal catalysts due to their acceptable activity and cost-effectiveness. However, there is an urgent need to further enhance their low-temperature activity and water resistance for industrial applications. Herein, CuO catalysts supported by various SiO2-TiO2 supports were prepared and evaluated for CO oxidation and NO reduction by CO reactions under the testing conditions with and without water. Among the studied catalysts with different SiO2 contents, CuO/5SiO2-TiO2, in which CuO was supported by SiO2-TiO2 with 5 wt.% SiO2, exhibited the best performance for CO oxidation. Compared with CuO/TiO2 and CuO/SiO2 reference catalysts, the CuO/5SiO2-TiO2 catalyst showed enhanced catalytic activity in both CO oxidation and NO reduction by CO under dry and wet conditions. Comprehensive characterizations revealed that the presence of SiO2 in TiO2 support facilitated the CuO/5SiO2-TiO2 catalyst with a high dispersion and reduced oxidation states of CuOx species. This not only improved the low-temperature reducibility but also enhanced the adsorption of reactive CO species. As a result, the CuO/5SiO2-TiO2 catalyst demonstrated superior catalytic activity. Furthermore, the inclusion of SiO2 in the catalyst inhibited H2O adsorption, contributing to the enhanced water resistance on CuO/5SiO2-TiO2 catalyst. These advantages in catalytic activity and water resistance make CuO/5SiO2-TiO2 a promising candidate for applications in emission control. [ABSTRACT FROM AUTHOR]

The potential collapsible deformation of loess surrounding rock is not conducive to the safety and stability of the tunnel, especially under rainfall conditions, which may induce severe engineering disasters. This paper analyzes the regularity of water infiltration in loess and failure response of tunnel structure under rainfall conditions. Rainfall infiltration in loess strata includes unsaturated infiltration and dominant channel infiltration. The dominant channels enhance soil permeability, leading to the overall downward movement of the wetting front, which provides conditions for the instability and failure of surrounding rock of loess tunnel. Through case statistics, the loess tunnel engineering disasters caused by rainfall are analyzed, elucidating the mechanism of tunnel instability and failure. Finally, according to the characteristics of loess surrounding rock and the response regularity of rainfall to tunnel structure, a series of engineering measures to prevent the deformation of surrounding rock and the specific construction method of loess tunnel structure safety warning system under the condition of rainfall are proposed. [ABSTRACT FROM AUTHOR]

Mediastinal haemangiomas pose diagnostic and therapeutic challenges owing to their rarity and complex anatomy. A 36-year-old man, with a history of smoking and drinking, presented with a posterior mediastinal mass with back pain. Initial investigations suggested a lymphangioma. However, owing to persistent symptoms and complex pathology, we performed surgical intervention involving open resection of the tumour, which was closely associated with the descending aorta and extended into the right posterior mediastinum. The surgical approach was influenced by the proximity of the tumour to vital structures, necessitating an open procedure. Postoperative complications included chylothorax, managed with a fat-free diet. The final pathological diagnosis was consistent with a benign vascular tumour with a low proliferative rate. Two months post-surgery, computed tomography revealed no complications, and the patient's pain had decreased. A multidisciplinary approach and surgical intervention played important roles in the diagnosis and treatment of this posterior mediastinal haemangioma. [ABSTRACT FROM AUTHOR]

Indium nitride (InN) is a promising photoelectrode material for photoelectrochemical (PEC) water splitting due to its strong light absorption capability, excellent electron mobility and direct band gap. However, the severe re-joining of the carrier in bulk or surface hinders the application of InN nanomaterials. Therefore, an InN nanorod/Ni(OH)2 heterojunction for PEC water splitting with enhanced interfacial charge transfer under a biased voltage was constructed first. In this case, the Ni(OH)2 catalyst not only has excellent electrocatalytic properties, but also can eliminate the surface state of the InN nanorods within a certain range. The improved InN/Ni(OH)2 photoelectrodes show that the photocurrent density of 4.43 mA cm−2, was 16 times higher than that of the pure InN nanorods (0.27 mA cm−2) at the same potential. Its applied bias photon-to-current efficiency (ABPE) at 0.92 V vs. Ag/AgCl was 6.92% with a 43-fold increase when compared to InN (0.16%). The work reported here, supplies practical and effective ideas to construct an InN-based nanorod heterojunction, thereby enhancing the redox reaction dynamics of the PEC water splitting in alkaline pH electrolyte. [ABSTRACT FROM AUTHOR]

Conjugated organic polymers (COPs), such as PM6, with attractive strong visible light absorption and good solution processability have been adopted as photocatalysts for building heterojunctions with InN nanorods for photoelectrochemical (PEC) water oxidation for the first time. Compared with the pure InN system, the PM6 photosensitive layer can effectively inhibit the severe charge recombination on the surface of the nanorod, and improve the kinetics of the oxygen evolution reaction (OER). In addition, the constructed Z-scheme heterojunction can consume the photogenerated holes from PM6 in a rapid and timely manner, thus improving the stability of the photoelectrode. Compared with the bare InN nanorods (0.12 mA cm−2), the improved photoanodes exhibit a significantly enhanced photocurrent density of 4.82 mA cm−2 at 1.45 V vs. RHE, respectively. Moreover, the current density of the photoanode protected by NiFe layered double hydroxide (LDH) can maintain approximately 80% of its initial value after continuous illumination in pH 13 electrolyte for 1 hour, indicating its long-term photochemical stability, which is the optimum value of the reported InN-based photoanodes. This means that InN-based photoanodes can achieve long-term stable PEC water splitting in a wide alkaline pH range, which can be directly used for PEC seawater splitting, eliminating the high cost and cumbersome process of seawater desalination. This work provides a promising method to construct group-III nitride-based photoanodes for high-performance PEC seawater splitting. [ABSTRACT FROM AUTHOR]

Background: Worldwide, gastric cancer is a leading cause of cancer incidence and mortality. This study aims to devise and validate a scoring system based on readily available clinical data to predict the risk of gastric cancer in a large Chinese population. Methods: We included a total of 6,209,697 subjects aged between 18 and 70 years who have received upper digestive endoscopy in Hong Kong from 1997 to 2018. A binary logistic regression model was constructed to examine the predictors of gastric cancer in a derivation cohort (n = 4,347,224), followed by model evaluation in a validation cohort (n = 1,862,473). The algorithm's discriminatory ability was evaluated as the area under the curve (AUC) of the mathematically constructed receiver operating characteristic (ROC) curve. Results: Age, male gender, history of Helicobacter pylori infection, use of proton pump inhibitors, non‐use of aspirin, non‐steroidal anti‐inflammatory drugs (NSAIDs), and statins were significantly associated with gastric cancer. A scoring of ≤8 was designated as "average risk (AR)". Scores at 9 or above were assigned as "high risk (HR)". The prevalence of gastric cancer was 1.81% and 0.096%, respectively, for the HR and LR groups. The AUC for the risk score in the validation cohort was 0.834, implying an excellent fit of the model. Conclusions: This study has validated a simple, accurate, and easy‐to‐use scoring algorithm which has a high discriminatory capability to predict gastric cancer. The score could be adopted to risk stratify subjects suspected as having gastric cancer, thus allowing prioritized upper digestive tract investigation. [ABSTRACT FROM AUTHOR]