High energy resolution fast XPS combined with TPD experiments were used to study the effect of chemisorbed oxygen on the adsorption and dissociation of NH(3) on Ir(110). Below 250 K the presence of O(ad) does not influence NH(3) decomposition. Above 250 K O(ad) enhances NH(3) dissociation, which results in three times as much N(2) formation and less molecular NH(3) desorption compared to the experiments without O(ad). The effect of O(ad) can be attributed to destabilization of NH(ad) on the surface, resulting in a further dehydrogenation towards N(ad). The presence of O(ad) on the surface lowers the temperature at which the N(ad) combination reaction takes place by as much as 200 K, due to repulsive interaction between N(ad) and O(ad). NO is formed above 450 K if both N(ad) and O(ad) are present on the surface.
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http://dx.doi.org/10.1039/b502350e | DOI Listing |
Anal Chem
January 2025
School of Metallurgy, Northeastern University, Shenyang 110819, China.
Sensitive H sensors play key roles in the large-scale and safe applications of H. In this study, we developed novel ternary Pd-loaded SnO@WO core-shell structures by hydrothermal and reduction methods. The compositions of the optimized ternary core-shell structures (Pd-SW-2) are prepared on the basis of the optimal binary core-shell structures (SW-X) according to the sensing performances to H.
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Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA.
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View Article and Find Full Text PDFACS Omega
January 2025
Faculty of Physics and Technology, Al-Farabi Kazakh National University, Al-Farabi ave. 71/23, 050040 Almaty, Kazakhstan.
This study investigates the formation of carbon dioxide clathrate hydrates under conditions simulating interstellar environments, a process of significant astrophysical and industrial relevance. Clathrate hydrates, where gas molecules are trapped within water ice cages, play an essential role in both carbon sequestration strategies and understanding of the behavior of ices in space. We employed a combination of Fourier Transform Infrared (FTIR) spectroscopy, mass spectrometry, temperature-programmed desorption (TPD), and Density Functional Theory (DFT) calculations to explore thin films of HO:CO ice mixtures with varying CO concentrations (5-75%) prepared by vapor deposition at temperatures ranging between 11 and 180 K.
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January 2025
Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China.
Proteolysis Targeting Chimeras (PROTACs) are bifunctional compounds that have been extensively studied for their role in targeted protein degradation (TPD). The capacity to degrade validated or undruggable targets provides PROTACs with significant potency in cancer therapy. However, the clinical application of PROTACs is limited by their poor potency and unfavorable pharmacokinetic properties.
View Article and Find Full Text PDFChembiochem
January 2025
Department de Farmacia I Tecnología Farmacèutica, I Fisicoquímica, Universitat de Barcelona, Av. Joan XXIII, 27-31, E-08028, Barcelona, Spain.
Targeting E3 ligases is a challenging area in drug discovery. Despite the human genome encoding for more than 600 E3 ubiquitin ligases, only a handful of E3 ligases have been pharmacologically modulated or exploited for targeted protein degradation (TPD) strategies. The main obstacle for hijacking these E3 ligases is the lack of small-molecule ligands.
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