Palladium nanoparticles (Pd NPs) were synthesized by the reduction-by-solvent method using polyvinylpirrolidone (PVP) as capping agent. The nonstatic interaction between PVP and the metallic surface may change the properties of the NPs due to the different possible interactions, through either the O or N atoms of the PVP. In order to analyze these effects and their repercussions in their catalytic performance, Pd NPs with various PVP/Pd molar ratios (1, 10, and 20) were prepared, deposited on silica, and tested in the formic acid decomposition reaction. The catalytic tests were conducted using catalysts prepared by loading NPs with three different time lapses between their purification and their deposition on the silica support (1 day, 1 month, and 6 months). CO adsorption, FTIR spectroscopy, XPS, and TEM characterization were used to determine the accessibility of the Pd NPs surface sites, the electronic state of Pd, and the average NPs size, respectively. The H production from the formic acid decomposition reaction has a strong dependence on the Pd surface features, which in turn are related to the NPs aging time due to the progressive removal of the PVP.
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http://dx.doi.org/10.1021/acs.langmuir.6b03149 | DOI Listing |
J Pharmacol Toxicol Methods
January 2025
Department of Pharmacy, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China; Department of Gastroenterology, the Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, China. Electronic address:
Background: Upadacitinib is a selective Janus kinase (JAK) 1 inhibitor approved by the Food and Drug Administration for the treatment of moderate-to-severe inflammatory bowel disease (IBD). We aimed to establish and validate a method for determining Upadacitinib in patients with IBD by liquid chromatography-tandem mass spectrometry (LC-MS/MS) method.
Methods: The mobile phase was 0.
Food Chem
December 2024
Wine Science Programme, School of Chemical Sciences, The University of Auckland | Waipapa Taumata Rau, 23 Symonds Street, Auckland 1010, New Zealand. Electronic address:
Grape marc, a by-product of winemaking, is a rich source of bioactive compounds, yet efficient extraction methods suitable for industrial application remain underexplored. This study presents an integrated, three-stage approach to optimise the extraction of anthocyanins, phenolics, and tannins from Merlot grape marc. In the first stage, 12 solvents were evaluated using conventional solvent extraction, with 50 % ethanol (EtOH) acidified with hydrochloric acid (HCl) achieving the highest anthocyanin recovery after eight extraction cycles (0.
View Article and Find Full Text PDFNat Prod Res
January 2025
College of Pharmacy, Guangxi Key Laboratory of Zhuang and Yao Ethnic Medicine, Guangxi University of Chinese Medicine, Nanning, China.
(L.) Jacq. has anti-inflammatory, analgesic, haemostatic and antioxidant effects, but its pharmacological components are still unclear.
View Article and Find Full Text PDFMolecules
January 2025
Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Longpan Road 159, Nanjing 210037, China.
Under mild conditions, formic acid effectively separates the components of lignocellulose, removing the majority of the hemicellulose and lignin from the cellulose. However, it has not yet been determined if multiple treatments with fresh formic acid may totally remove hemicellulose and lignin. In this study, fresh formic acid was used to repeatedly pretreat the bamboo powder, and the effect of multiple treatments on the physicochemical structure of the bamboo powder was investigated using changes in fractions, enzymatic hydrolysis, hydrophilicity, cellulose crystallinity, and lignin structure.
View Article and Find Full Text PDFOrg Lett
January 2025
Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 116023 Dalian, Liaoning, People's Republic of China.
A straightforward and efficient nickel-catalyzed cyclization/carbonylation transformation of -allylbromoacetamides toward the synthesis of 2-pyrrolidinone derivatives has been developed with arylboronic acids as the reaction partner. This transformation proceeds through a sequential single-electron-transfer pathway via 5-- cyclization and carbonyl insertion steps, furnishing a variety of 2-pyrrolidinone derivatives in good yields. Various useful functional groups were well tolerated.
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