We study a model of a light-induced proton pump in artificial reaction centers. The model contains a molecular triad with four electron states (i.e., one donor state, two photosensitive group states, and one acceptor state) as well as a molecular shuttle having one electron and one proton-binding sites. The shuttle diffuses between the sides of the membrane and translocates protons energetically uphill: from the negative side to the positive side of the membrane, harnessing for this purpose the energy of the electron-charge separation produced by light. Using the methods of quantum transport theory we calculate the range of light intensity and transmembrane potentials that maximize both the light-induced proton current and the energy transduction efficiency. We also study the effect of temperature on proton pumping. The light-induced proton pump in our model gives a quantum yield of proton translocation of about 55%. Thus, our results explain previous experiments on these artificial photosynthetic reaction centers.
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http://dx.doi.org/10.1063/1.3170939 | DOI Listing |
J Strength Cond Res
December 2024
School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, United Kingdom.
Kember, LS, Riehm, CD, Schille, A, Slaton, JA, Myer, GD, and Lloyd, RS. Residual biomechanical deficits identified with the tuck jump assessment in female athletes 9 months after ACLR surgery. J Strength Cond Res 38(12): 2065-2073, 2024-Addressing biomechanical deficits in female athletes after anterior cruciate ligament reconstruction (ACLR) is crucial for safe return-to-play.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, State Key Laboratory of Crystal Material, Shandong University, Jinan 250100, China.
Architecting Prussian blue analogue (PBA) cathodes with optimized synergistic bimetallic reaction centers is a paradigmatic strategy for devising high-energy sodium-ion batteries (SIBs); however, these cathodes usually suffer from fast capacity fading and sluggish reaction kinetics. To alleviate the above problems, herein, a series of early transition metal (ETM)-late transition metal (LTM)-based PBA (Fe-VO, Fe-TiO, Fe-ZrO, Co-VO, and Fe-Co-VO) cathode materials have been conveniently fabricated via an "acid-assisted synthesis" strategy. As a paradigm, the FeVO-PBA (FV) delivers a superb rate capability (148.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Well-defined single-atom catalysts (SACs) serve as ideal model systems for directly comparing experimental results with theoretical calculations, offering profound insights into heterogeneous catalytic processes. However, precisely designing and controllably synthesizing SACs remain challenging due to the unpredictable structure evolution of active sites and generation of embedded active sites, which may bring about steric hindrance during chemical reactions. Herein, we present the precious nonpyrolysis synthesis of Re SACs with a well-defined phenanthroline coordination supported by NiO (Re-phen/NiO).
View Article and Find Full Text PDFLangmuir
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 PDFAnal Chem
January 2025
State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Hydroquinone (HQ) and copper ions (Cu) are categorized as environmental pollutants that are severely limited in water. Designing a selective assay for discriminating HQ from its two isomers and the convenient determination of Cu is of great importance. Herein, a Tb-based metal-organic framework (Tb-MOF) and HQ are assembled innovatively into a ratiometric fluorescence nanoprobe to selectively distinguish HQ and subsequent quantitative visual detection of Cu.
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