Hydrogen sensing by sol-gel grown NiO and NiO:Li thin films

Hydrogen sensors have been prepared using nickel oxide (NiO) and lithium-doped nickel oxide (NiO:Li) thin films, deposited on glass substrates by the sol-gel spin coating technique. The surface morphology, structure, optical and electrical properties of the obtained films were studied. Hydrogen sensing results are presented for three operating temperatures (140, 160, and 180 {\deg}C) and for hydrogen concentrations ranging from 1000 to 15000 ppm in synthetic air. The NiO and NiO:Li (2% and 8% doping concentrations) sensors show maximum responses for the operating temperature of 180 {\deg}C. When tested at different hydrogen concentrations in air, the lithium-doped NiO sensors showed a higher response than the undoped NiO films

High-resolution and functional magnetic resonance imaging of the brachial plexus using an isotropic 3D T2 STIR (Short Term Inversion Recovery) SPACE sequence and diffusion tensor imaging

This technical note demonstrates the relevance of the isotropic 3D T2 turbo-spin-echo (TSE) sequence with short-term inversion recovery (STIR) and variable flip angle RF excitations (SPACE: Sampling Perfection with Application optimized Contrasts using different flip angle Evolutions) for high-resolution brachial plexus imaging. The sequence was used in 11 patients in the diagnosis of brachial plexus pathologies involving primary and secondary tumors, and in six volunteers. We show that 3D STIR imaging is not only a reliable alternative to 2D STIR imaging, but it also better evaluates the anatomy, nerve site compression and pathology of the plexus, especially to depict space-occupying tumors along its course. Finally, due to its appropriate contrast we describe how 3D-STIR can be used as a high-resolution mask to be fused with fraction of anisotropy (FA) maps calculated from diffusion tensor imaging (DTI) data of the plexu

Carcinome papillaire sur kyste du tractus thyreoglosse

Introduction :: Cysts of the thyroglossal duct are a congenital anomaly. they are common but the incidence of papillary carcinoma arising in a thyroglossal duct cyst (TDC) is rare. The clinical presentation of these cancers is generally nonspecific. There are usually identified only after histopathologic examinationAim: Modalities of treatment and prevention are discussed.Methods: We report 4 cases of a papillary carcinoma developed on a thyroglossal duct cyst, who underwent surgery. Two cases have been detected on préopératory and two at the definitive anatomopathology. Our therapeutic attitude has been discussed in each of our 4cases.Conclusion: there is no consensus about the modalities of treatment of papillary carcinoma in thyroglossal duct cyst.Keywords: Thyroglossal duct cyst, Thyroid, Papillary carcinoma, surgery, Total thyroidectomy

Design of highly anti-corrosive electroless plated Ni-P/modified halloysite nanotubes nanocomposite coating

Halloysite nanotubes (HNTs) and their modifications with either NH2 (HNT-NH2) or NH2/Polypyrrole (HNT–NH2–PPy) were electroless-deposited into the NiP matrix for the first time to form NiP/HNT, NiP/HNT-NH2 and NiP/HNT–NH2–PPy nanocomposite coatings. The as-prepared nanocomposite coatings were heat-treated at 400 °C for 1 h. The transformation in microstructure, nanoindentation, Vicker's micro-hardness, surface morphology, and anti-corrosive properties of all prepared composite coatings were compared to the HNT-free (NiP) coating. Incorporating HNTs in the NiP coating made an appreciable enhancement in the hardness and corrosion resistance. Using the electrochemical impedance spectroscopy technique (EIS), the NiP/HNT-NH2 and NiP/HNT–NH2–PPy coatings showed more significant levels of enhancement in anticorrosion performance, offering about 16.5% and 25.4%, respectively, an increase in the inhibition efficiency of unmodified one (NiP/HNT), reached to 73 and 82%. Moreover, the modified HNT coatings revealed slightly high levels of betterment in microhardness, about 9% and 5.4% for HNT modification with NH2 and NH2-PPy, respectively. In addition, the heat treatment extra improved the hardness and the corrosion resistance of all HNTs nanocomposite coatings compared to HNT-free coating. Furthermore, the heat-treated NiP/HNT has the highest protection efficiency reached to about 95%, based on the polarization measurements. This momentous improvement in the hardness and electrochemical properties reflects the effect of adding the pristine and the modified HNTs into the NiP matrix, resulting in the development of high-performance NiP/HNT-NH2 and NiP/HNT–NH2–PPy composite coatings facilitating their use in various industries.This publication was made possible by NPRP grant 13S-0117-200095 from the Qatar National Research Fund (QNRF) (a member of the Qatar Foundation). Statements made herein are solely the responsibility of the authors. This work also is supported by Qatar University through High Impact Grant, QUHI-CAM-22/23-550. The authors would like to acknowledge the Central Laboratory Unit (CLU) efforts, Qatar University, for SEM, EDX, TEM analyses, and elemental mapping. The authors also thank the Gas Processing Center (GPC) at Qatar University for conducting the XPS analysis. The publication of this article was funded by Qatar National Library.Scopu

Data on the fabrication of hybrid calix [4]arene-modified natural bentonite clay for efficient selective removal of toxic metals from wastewater at room temperature

Fresh water resources on the earth are less than 0.2%; meanwhile, around 80% of the freshwater is consumed daily in agriculture, industries, and household activities [1–2]. There is an essential need to develop efficient adsorbents for wastewater treatment [1–6], in this regards, hereafter we present the rationale synthesis and characterization of hybrid natural bentonite clay modified with Calix [4] arene (denoted as B-S-Calix) as efficient adsorbents for toxic metals from wastewater. This is driven by the facile photo-radical thiol-yne addition among the thiolated clay and an alkynylated calix[4]arene. The morphology, surface modifications, and Thermal degradation of B, B-S, and B-S-Calix were investigated using TEM, FTIR, and TGA techniques. The adsorption performance of B, BS and B-S-Calix towards toxic metals including cadmium (II) ion [Cd (II)], zinc (II) ion [Zn(II)], lead(II) ion [Pb(II)], strontium(II) ion [Sr (II)], cobalt(II) ion [Co (II)], copper(II) ion [Cu(II)], and mercury (II) ion [Hg(II)] from wastewater were benchmarked 25 °C. These data are related to the article entitled “hybrid Clay/Calix[4]arene Calix[4]arene-clicked clay through thiol-yne addition for the molecular recognition and removal of Cd(II) from wastewater’’ [7]

Carbon-supported catalysts for carbon dioxide methanation: A review

Carbon-based materials have attracted significant attention in various catalytic applications. However, they are rarely reported for high-temperature catalytic reactions, owing to their limited thermal stability compared to other common materials such as silica and alumina, especially in oxidation reactions. CO2 methanation became a pivotal research hotspot due to its ability to contribute to greenhouse gas mitigation. In addition, CO2 methanation reactions can be carried out below 400 °C in a hydrogen atmosphere, which suits the thermal stability of many modified carbon materials. However, the number of reviews on CO2 methanation does not match the huge number of the experimental publications on CO2 methanation particularly reviews on carbon-supported catalysts. Motivated by the paucity of literature, including reviews on carbon-supported catalysts for CO2 methanation, this review is focused on the catalytic performance of the carbon-supported catalysts of CO2 methanation. It offers significant comparisons among all reported carbon-supported catalysts, providing a comprehensive study on the effect of the carbonaceous supports, such as graphene, biochar, and carbon nanotubes on the catalytic activity. In addition, it investigates the impact of promoters on the catalytic performance of the carbon-supported catalysts in CO2 methanation and highlights the preparation methods and their optimized metal compositions that lead to the highest activity and selectivity. We conclude with a brief synopsis on the current challenges and perspectives on the future directions. This study paves the way for broader usage of carbon-supported catalysts for different thermal catalytic applications, not limited to CO2 methanation.This work was supported by (i) the Qatar Research Development and Innovation Council (QRDI, a member of the Qatar Foundation, through the Academic Research Grant (ARG01-0530-230416), (ii) Qatar University through an International Research Collaboration Co-Fund grant, IRCC-2023-015, and (iii) South Africa’s National Foundation of Research (NRF) through the DSI-NRF-Wits SARChI Chair in Materials Electrochemistry and Energy Technologies (MEET) (UID No.: 132739)

Characterization of Nd3+-doped Tellurite Glasses with Low OH Content

This work presents the results of the investigation of structural and thermal properties of Nd3+-doped tellurite glasses with low OH content. The samples were characterized by XRD, FTIR, DTA, UV/VIS/NIR and Archimedes’ method. Tellurite glasses of composition (100 – x)(0.8TeO2 + 0.2WO3) + xNd2O3 (x = 0, 0.05, 0.5, 1, 2, and 4 mol%) were prepared in both ambient and oxygen atmospheres. All samples showed an increase of the values of Tg, Tx, and Tx-Tg with Nd2O3 addition. The reduction of OH content implies a slight decrease of Tg. The density and the molar volume of the glasses increased with Nd2O3. The intensity of the absorption bands associated with Te-O bonds of TeO4 units decreased compared with the bands associated with Te-O bonds of TeO3+1/3 units. This indicates that Nd2O3 favors the transformation of the TeO4 groups in TeO3 groups via TeO3+1, increasing the NBOs and contributing to the formation of strongly hydrogen-bonded OH groups. The samples made in O2 showed a reduction of 48% of “free” OH ions compared with the Amb ones

Effects of pre-operative isolation on postoperative pulmonary complications after elective surgery: an international prospective cohort study

We aimed to determine the impact of pre-operative isolation on postoperative pulmonary complications after elective surgery during the global SARS-CoV-2 pandemic. We performed an international prospective cohort study including patients undergoing elective surgery in October 2020. Isolation was defined as the period before surgery during which patients did not leave their house or receive visitors from outside their household. The primary outcome was postoperative pulmonary complications, adjusted in multivariable models for measured confounders. Pre-defined sub-group analyses were performed for the primary outcome. A total of 96,454 patients from 114 countries were included and overall, 26,948 (27.9%) patients isolated before surgery. Postoperative pulmonary complications were recorded in 1947 (2.0%) patients of which 227 (11.7%) were associated with SARS-CoV-2 infection. Patients who isolated pre-operatively were older, had more respiratory comorbidities and were more commonly from areas of high SARS-CoV-2 incidence and high-income countries. Although the overall rates of postoperative pulmonary complications were similar in those that isolated and those that did not (2.1% vs 2.0%, respectively), isolation was associated with higher rates of postoperative pulmonary complications after adjustment (adjusted OR 1.20, 95%CI 1.05-1.36, p = 0.005). Sensitivity analyses revealed no further differences when patients were categorised by: pre-operative testing; use of COVID-19-free pathways; or community SARS-CoV-2 prevalence. The rate of postoperative pulmonary complications increased with periods of isolation longer than 3 days, with an OR (95%CI) at 4-7 days or ≥ 8 days of 1.25 (1.04-1.48), p = 0.015 and 1.31 (1.11-1.55), p = 0.001, respectively. Isolation before elective surgery might be associated with a small but clinically important increased risk of postoperative pulmonary complications. Longer periods of isolation showed no reduction in the risk of postoperative pulmonary complications. These findings have significant implications for global provision of elective surgical care