We have observed an exchange of (18)O in the reactions of CO(2) with peroxynitrite using membrane-inlet mass spectrometry and HPLC negative electrospray ionization mass spectrometry. The exchange appeared on addition of peroxynitrite to a solution containing (18)O-labeled CO(2) in equilibrium with bicarbonate. It was observed as a temporarily enhanced rate of depletion of (18)O from CO(2), a rate that was greater than the rate of (18)O depletion caused by the hydration/dehydration cycle of CO(2). In addition, we detected the appearance of mass peaks attributed to (18)O in product NO(3)(-). As a further measure of the (18)O exchange, there was a redistribution of (18)O such that the ratio of doubly to singly labeled CO(2) could not be described by the binomial expansion. This is not due to the hydration/dehydration cycle of CO(2) but most likely to recycling of CO(2) in the reaction with peroxynitrite. This (18)O exchange associated with the reactions of CO(2) and peroxynitrite may open a new methodology for studying this significant process.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.freeradbiomed.2004.09.028 | DOI Listing |
Langmuir
January 2025
Centre for Energy (M473), The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
The mechanisms of NO reduction by CO over nitrogen-doped graphene (N-graphene)-supported single-atom Ni catalysts in the presence of O, HO, CO, and SO have been studied via density functional theory (DFT) modeling. The catalyst is represented by a single Ni atom bonded to four N atoms on N-graphene. Several alternative reaction pathways, including adsorption of NO on the Ni site, direct reduction of NO by CO, decomposition of NO to NO followed by reduction of NO to N, formation of active oxygen radical O*, and reduction of O* by CO, were hypothesized and the energy barrier corresponding to each of the reaction steps was calculated using DFT.
View Article and Find Full Text PDFLangmuir
January 2025
Heilongjiang Provincial Key Laboratory of CO2 Resource Utilization and Energy Catalytic Materials, School of Material Science and Chemical Engineering, Harbin University of Science and Technology, Harbin 150040, China.
Constructing wide and narrow band gap heterogeneous semiconductors is a method to improve the activity of photocatalysts. In this paper, CMS/ZnO heterojunctions were prepared by solvothermal loading of ZnO particles on the surface of CuMoS nanosheets. The photocatalytic H precipitation rate is about 545 μmol·g·h, which is 6.
View Article and Find Full Text PDFAppl Biochem Biotechnol
January 2025
Department of Internal Medicine-Cardiovascular, Guangzhou Twelfth People's Hospital, No.1, Tianqiang Road, Tianhe District, Guangzhou City, Guangdong Province, 510620, China.
Myocardial infarction (MI) is a coronary artery-related disease that seriously threatens human life and is the leading cause of sudden death worldwide, where a lack of nutrients and oxygen leads to an inflammatory response and death of cardiomyocytes. Ferroptosis is a form of non-apoptotic cell death associated with metabolic dysfunction, resulting in abnormal breakdown of glutamine and iron-dependent accumulation of reactive oxygen species (ROS) during metabolism. However, the molecular mechanism of ferroptosis in the pathogenesis of MI and the function of Klotho and KRAS on ferroptosis during MI remain unclear.
View Article and Find Full Text PDFLasers Med Sci
January 2025
Hangzhou Third People's Hospital, Hangzhou, China.
Background: Post-inflammatory hyperpigmentation (PIH) is a common cosmetic concern, often leading to significant psychological distress for the patients. With the widespread application of lasers including ablative fractional resurfacing (AFR) with a 10,600 nm CO laser, PIH caused by lasers is becoming increasingly common. But due to the absence of an appropriate animal research model, our understanding of pathophysiological mechanisms and preventive strategies for PIH remains limited.
View Article and Find Full Text PDFJ Mol Model
January 2025
School of National Defense & Nuclear Science and Technology, Southwest University of Science and Technology, Mianyang, 621010, People's Republic of China.
To clarify the effect of heating rate on the thermal decomposition process of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB), this study employs molecular dynamic simulations to investigate the thermal decomposition of TATB at heating rates of 20, 40, 60, and 80 K/ps. The initial temperature is uniformly set to 300 K, while the final temperature is set to 3000 K. Results indicate that within the temperature range of 300-3000 K, the thermal decomposition rate of TATB decreases with increasing heating rate, whereas the initial decomposition temperature of TATB increases, consistent with the experimental pattern.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!