The design of new amphoteric catalysts is of great interest for several industrial processes, especially those covering dehydration and dehydrogenation phenomena. Adsorption microcalorimetry was used to monitor the design of mixed oxides of zinc with Group 3 elements (aluminium, gallium, indium) with amphoteric character and enhanced specific surface area. Acid-base features were found to evolve non-linearly with the relative amounts of metal, and the strengths of the created acidic or basic sites were measured by adsorption microcalorimetry. A panel of bifunctional catalysts of various acid-base (amounts, strengths) and redox character was obtained. Besides, special interest was given to In-Zn mixed oxides for their enhanced basicity: this series of catalysts displays important basic features of high strength (q(diff) (SO₂ ads.) > 200 kJ mol(SO₂)⁻¹ in substantial amounts (1 - 2 μmol m(catalyst)⁻²), whose impact on efficiency or selectivity in catalytic dehydration/dehydrogenation can be valuable.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1039/c2cp23613c | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Effect of Multiple Firing Cycles on Shear Bond Strength Between Zirconia and Lithium Disilicate.
Med Sci Monit
January 2025
College of Dentistry, King Khalid University, Abha, Saudi Arabia.
BACKGROUND Indirect ceramic restorations often need multiple firings to match the shade of natural teeth or need after-correction and ceramic addition during the clinical trial stage. Many studies have examined how multiple firings affect the mechanical characteristics of zirconia-veneered prostheses. The effect of firing number on adhesion between these core and heat-pressed lithium disilicate veneering ceramics is unclear.
View Article and Find Full Text PDFUrea Complexation for Docosahexaenoic Acid Enrichment from Crypthecodinium cohnii Oil: Using Water as the Urea Solvent.
J Oleo Sci
January 2025
College of Marine Biology, Xiamen Ocean Vocational College.
Based on the observation that urea, water, and ethyl esters (EE) can form gypsum-like mixtures, this study explored the feasibility of employing water as a solvent for urea in the urea complexation method to enrich n-3 polyunsaturated fatty acids with docosahexaenoic acid (DHA)-containing ethyl esters (DHA- EE) from Crypthecodinium cohnii as the material. Under the conditions of a urea/DHA-EE ratio of 3, a water/DHA-EE ratio of 0.75, a mixing temperature of 65℃, and a cooling temperature of 20℃, a concentrate containing over 90% DHA was achieved.
View Article and Find Full Text PDFN-Heterocyclic Carbene Deposition on a Copper Powder Surface Using Mechanochemistry.
ACS Appl Mater Interfaces
January 2025
Department of Chemistry, McGill University, Montréal, Québec H3A 0G4, Canada.
Metal powders are crucial precursors for manufacturing surfaces through thermal spraying, cold spraying, and 3D printing methods. However, surface oxidation of these precursors poses a challenge to the coherence of the metallic materials during manufacturing processes. Herein, we introduce a method for surface modification of copper powder with N-heterocyclic carbenes (NHCs) using mechanochemistry to mitigate surface oxidation.
View Article and Find Full Text PDFEffects of Tasimelteon Treatment on Traumatic Brain Injury Through NRF-2/HO-1 and RIPK1/RIPK3/MLKL Pathways in Rats.
Mol Neurobiol
January 2025
Department of Pathology, Faculty of Veterinary Medicine, Burdur Mehmet Akif Ersoy University, Burdur, Turkey.
Secondary brain damageafter traumatic brain injury (TBI) involves oxidative stress, neuroinflammation, apoptosis, and necroptosis and can be reversed by understanding these molecular pathways. The objective of this study was to examine the impact of tasimelteon (Tasi) administration on brain injury through the nuclear factor erythroid 2-related factor 2 (NRF-2)/heme oxygenase-1 (HO-1) and receptor-interacting protein kinase 1 (RIPK1)/receptor-interacting protein kinase 3 (RIPK3)/mixed lineage kinase domain-like (MLKL) pathways in rats with TBI. Thirty-two male Wistar albino rats weighing 300-350 g were randomly divided into four groups: the control group, trauma group, Tasi-1 group (trauma + 1 mg/kg Tasi intraperitoneally), and Tasi-10 group (trauma + 10 mg/kg Tasi intraperitoneally).
View Article and Find Full Text PDFSize-Dependent Reduction Kinetics of Iron Oxides in Single and Mixed Mineral Systems.
Environ Sci Technol
January 2025
Geomicrobiology, Department of Geosciences, University of Tübingen, 72076 Tübingen, Germany.
Iron(III) (oxyhydr)oxide minerals with varying particle sizes commonly coexist in natural environments and are susceptible to both chemical and microbial reduction, affecting the fate and mobility of trace elements, nutrients, and pollutants. The size-dependent reduction behavior of iron (oxyhydr)oxides in single and mixed mineral systems remains poorly understood. In this study, we used microbial and mediated electrochemical reduction approaches to investigate the reduction kinetics and extents of goethite and hematite.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!