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The suitability of two different low-grade kaolinitic clays and limestone locally available in Switzerland to produce a limestone calcined-clay cement at industrial scale was investigated. Firstly, the clays characteristics related to reactivity were presented. Then, the effect of calcined clays on cement performance was explored according to EN 197-5 and EN 197-1 requirements. Finally, the new cement was produced at industrial scale by using a Swiss cement plant equipped with a Lepol kiln for clay calcination and clinker production and used to manufacture 3 different concretes mixes for 3 different environmental exposure classes (EN 206). The concrete mixes were tested for mechanical and durability performance. The results show that the two calcined low-grade clays are suitable to produce a limestone calcined-clay cement classified as CEM II/C-M (Q-LL). Moreover, all the 3 concretes manufactured with the new cement meet the minimum mechanical and durability standard requirements of the corresponding exposure classes. [ABSTRACT FROM AUTHOR]

One of the major challenges of nano-biotechnology is to engineer potent antimicrobial nanostructures (NS) with high biocompatibility. Keeping this in view, we have performed aqueous olive leaf extract mediated one pot facile synthesis of CuO-NS and CeO2-NS. Prepared NS were homogenous, less than 26 nm in size, and small crystallite units as revealed by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses. Fourier transform infrared spectroscopy (FTIR) of CuO-NS and CeO2-NS showed typical Cu-O prints around 592–660 cm-1 and Ce-O bond vibrations at 453 cm-1. The successful capping of CuO-NS and CeO2-NS by compounds present in the plant extract was further validated by high performance liquid chromatography (HPLC) and thermal gravimetric analysis (TGA). Active phyto-chemicals from the leaf extract simultaneously acted as strong reducing as well as capping agent in the NS synthesis. NS engineered in the present study showed antibacterial potential at extremely low concentration against highly virulent multidrug-resistant (MDR) gram-negative strains (Escherichia coli , Enterobacter cloacae , Acinetobacter baumannii and Pseudomonas aeruginosa), alarmed by World Health Organization (WHO). Furthermore, CuO-NS and CeO2-NS did not show any cytotoxicity on HEK-293 cell lines and Brine shrimp larvae indicating that the NS green synthesized in the present study are biocompatible. [ABSTRACT FROM AUTHOR]

To grapple with cancer, implementation of differentially cytotoxic nanomedicines have gained prime attention of the researchers across the globe. Now, ceria (CeO2) at nanoscale has emerged as a cut out therapeutic agent for malignancy treatment. Keeping this in view, we have fabricated SnxCe1-xO2 nanostructures by facile, ecofriendly, and biocompatible hydrothermal method. Structural examinations via XRD and FT-IR spectroscopy have revealed single phase cubic-fluorite morphology while SEM analysis has depicted particle size ranging 30-50nm for pristine and doped nanostructures. UV-Vis spectroscopy investigation explored that Sn doping significantly tuned the band gap (eV) energies of SnxCe1-xO2 nanostructures which set up the base for tremendous cellular reactive oxygen species (ROS) generations involved in cancer cells’ death. To observe cytotoxicity, synthesized nanostructures were found selectively more toxic to neuroblastoma cell lines as compared to HEK-293 healthy cells. This study anticipates that SnxCe1-xO2 nanostructures, in future, might be used as nanomedicine for safer cancer therapy. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (Ag-NPs) synthesized through reduction by Otostegia limbata green extract are, hereby, reported for the first time. It is very interesting to observe that in this case, O. limbata plant extract acts as a strong chelating agent in Ag-NPs formation through AgNO3. Scanning electron microscope (SEM) studies expose that Ag-NPs formation is highly homogenous and spherical with mean particle size of 32 ± 0.8 nm. A typical Ag absorption peak has been observed at 419 nm by ultra violet (UV)-visible spectroscopy which have endorsed the successful formation of single phase Ag-NPs. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) examination further validates the crystalline pure phase structure of Ag-NPs. Promising results have been recorded against protein kinase inhibition assay and antibacterial assay having prominent pathogenic strains. Our present study explores that biosynthesized eco-friendly Ag-NPs have great potential, in the future, for anticancer drug development with wide range pharmaceutical applications. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO 2 ) and carbon monoxide (CO) hydrogenation to methane (CH 4 ) or methanol (MeOH) is a promising pathway to reduce CO 2 emissions and to mitigate dependence on rapidly depleting fossil fuels. Along these lines, a series of catalysts comprising copper (Cu) or palladium (Pd) nanoparticles (NPs) supported on zinc oxide (ZnO) as well as bimetallic CuPd NPs supported on ZnO or graphene were synthesized via various methodologies. The prepared catalysts underwent comprehensive characterization via high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDX) mapping, electron energy loss spectroscopy (EELS), X-ray diffraction (XRD), hydrogen temperature-programmed reduction and desorption (H 2 -TPR and H 2 -TPD), and deuterium temperature-programmed desorption (D 2 O-TPD). In the CO 2 hydrogenation process carried out at 20 bar and elevated temperatures (300 to 500 °C), Cu, Pd, and CuPd NPs (<5 wt% loading) supported on ZnO or graphene predominantly yielded CH 4 as the primary product, with CO generated as a byproduct via the reverse water gas shift (RWGS) reaction. For CO hydrogenation between 400 and 500 °C, the CO conversion was at least 40% higher than the CO 2 conversion, with CH 4 and CO 2 identified as the main products, the latter from water gas shift. Employing 90 wt% Cu on ZnO led to an enhanced CO conversion of 14%, with the MeOH yield reaching 10% and the CO 2 yield reaching 4.3% at 230 °C. Overall, the results demonstrate that lower Cu/Pd loading (<5 wt%) supported on ZnO/graphene favored CH 4 production, while higher Cu content (90 wt%) promoted MeOH production, for both CO 2 and CO hydrogenation at high pressure., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

Adding photocatalytically active TiO 2 nanoparticles (NPs) to polymeric paints is a feasible route toward self-cleaning coatings. While paint modification by TiO 2 -NPs may improve photoactivity, it may also cause polymer degradation and release of toxic volatile organic compounds. To counterbalance adverse effects, a synthesis method for nonmetal (P, N, and C)-doped TiO 2 -NPs is introduced, based purely on waste valorization. PNC-doped TiO 2 -NP characterization by vibrational and photoelectron spectroscopy, electron microscopy, diffraction, and thermal analysis suggests that TiO 2 -NPs were modified with phosphate (P=O), imine species (R=N-R), and carbon, which also hindered the anatase/rutile phase transformation, even upon 700 °C calcination. When added to water-based paints, PNC-doped TiO 2 -NPs achieved 96% removal of surface-adsorbed pollutants under natural sunlight or UV, paralleled by stability of the paint formulation, as confirmed by micro-Fourier transform infrared (FTIR) surface analysis. The origin of the photoinduced self-cleaning properties was rationalized by three-dimensional (3D) and synchronous photoluminescence spectroscopy, indicating that the dopants led to 7.3 times stronger inhibition of photoinduced e - /h + recombination when compared to a benchmark P25 photocatalyst., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

The sensing of volatile organic compounds by composites containing metal oxide semiconductors is typically explained via adsorption-desorption and surface electrochemical reactions changing the sensor's resistance. The analysis of molecular processes on chemiresistive gas sensors is often based on indirect evidence, whereas in situ or operando studies monitoring the gas/surface interactions enable a direct insight. Here we report a cross-disciplinary approach employing spectroscopy of working sensors to investigate room temperature methanol detection, contrasting well-characterized nanocomposite (TiO 2 @rGO-NC) and reduced-graphene oxide (rGO) sensors. Methanol interactions with the sensors were examined by (quasi) operando -DRIFTS and in situ -ATR-FTIR spectroscopy, the first paralleled by simultaneous measurements of resistance. The sensing mechanism was also studied by mass spectroscopy (MS), revealing the surface electrochemical reactions. The operando and in situ spectroscopy techniques demonstrated that the sensing mechanism on the nanocomposite relies on the combined effect of methanol reversible physisorption and irreversible chemisorption, sensor modification over time, and electron/O 2 depletion-restoration due to a surface electrochemical reaction forming CO 2 and H 2 O., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

One of the major challenges of nano-biotechnology is to engineer potent antimicrobial nanostructures (NS) with high biocompatibility. Keeping this in view, we have performed aqueous olive leaf extract mediated one pot facile synthesis of CuO-NS and CeO 2 -NS. Prepared NS were homogenous, less than 26 nm in size, and small crystallite units as revealed by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses. Fourier transform infrared spectroscopy (FTIR) of CuO-NS and CeO 2 -NS showed typical Cu-O prints around 592-660 cm -1 and Ce-O bond vibrations at 453 cm -1 . The successful capping of CuO-NS and CeO 2 -NS by compounds present in the plant extract was further validated by high performance liquid chromatography (HPLC) and thermal gravimetric analysis (TGA). Active phyto-chemicals from the leaf extract simultaneously acted as strong reducing as well as capping agent in the NS synthesis. NS engineered in the present study showed antibacterial potential at extremely low concentration against highly virulent multidrug-resistant (MDR) gram-negative strains ( Escherichia coli , Enterobacter cloacae , Acinetobacter baumannii and Pseudomonas aeruginosa ), alarmed by World Health Organization (WHO). Furthermore, CuO-NS and CeO 2 -NS did not show any cytotoxicity on HEK-293 cell lines and Brine shrimp larvae indicating that the NS green synthesized in the present study are biocompatible.

This article reports the green fabrication of cerium oxide nanoparticles (CeO 2 NPs) using Olea europaea leaf extract and their applications as effective antimicrobial agents. O. europaea leaf extract functions as a chelating agent for reduction of cerium nitrate. The resulting CeO 2 NPs exhibit pure single-face cubic structure, which is examined by X-ray diffraction, with a uniform spherical shape and a mean size 24 nm observed through scanning electron microscopy and transmission electron microscopy. Ultraviolet-visible spectroscopy confirms the characteristic absorption peak of CeO 2 NPs at 315 nm. Fourier transform infrared spectroscopy reflects stretching frequencies at 459 cm -1 , showing utilization of natural components for the production of NPs. Thermal gravimetric analysis predicts the successful capping of CeO 2 NPs by bioactive molecules present in the plant extract. The antimicrobial studies show significant zone of inhibition against bacterial and fungal strains. The higher activities shown by the green synthesized NPs than the plant extract lead to the conclusion that they can be effectively used in biomedical application. Furthermore, reduction of cerium salt by plant extract will reduce environmental impact over chemical synthesis., Competing Interests: The authors report no conflicts of interest in this work.