We investigate O(2) interaction with various metalloporphyrins (MnP, FeP, CoP, and NiP) using ab initio calculations based on density-functional theory. We discuss the trends in the activation barriers for the O-O bond cleavage in relation to the geometric, vibrational, electronic, and energetic properties of the systems. Whether the lowest unoccupied molecular orbital-highest occupied molecular orbital (LUMO-HOMO) levels of the metalloporphyrins involve the corresponding metal centers depends on the d orbital occupancies of the metals. We found that activation barriers for the O(2) dissociation can be mainly determined from the LUMO-HOMO characters of the metalloporphyrins, and consequently the FeP is the best catalyst with respect to the O(2) interaction from adsorption to dissociation.
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http://dx.doi.org/10.1063/1.1947187 | DOI Listing |
Adv Sci (Weinh)
January 2025
Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade, Taipa, Macau SAR, 999078, China.
Potassium-sulfur (K-S) batteries are severely limited by the sluggish reaction kinetics of the cyclooctasulfur (cyclo-S) electrode with low conductivity, which urgently requires a novel cathode to facilitate activity to improve sulfur utilization. In this study, using the wet chemistry method, the molecular clip of Li is created to replace cyclo-S molecular with the highly active chain-like S molecular. The molecular clip strategy effectively lowers the reaction barrier in potassium-sulfur systems, and the stretching of S─S bonds weakens the binding between sulfur atoms, facilitating the transformation of potassium polysulfides (KPSs).
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Frontiers Science Center for Deep Ocean Multispheres and Earth Systems, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education/Sanya Oceanographic Institution, Ocean University of China, Qingdao/Sanya, 266003/572024, China.
The scarcity of effective neuroprotective agents and the presence of blood-brain barrier (BBB)-mediated extremely inefficient intracerebral drug delivery are predominant obstacles to the treatment of cerebral ischemic stroke (CIS). Herein, ROS-responsive borneol-based amphiphilic polymeric NPs are constructed by using traditional Chinese medicine borneol as functional blocks that served as surface brain-targeting ligand, inner hydrophobic core for efficient drug loading of membrane-permeable calcium chelator BAPTA-AM, and neuroprotective structural component. In MCAO mice, the nanoformulation (polymer: 3.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Warshel Institute for Computational Biology, School of Life and Health Sciences, School of Medicine, The Chinese University of Hong Kong (Shenzhen), Shenzhen 518172, China.
The parathyroid hormone type 1 receptor (PTH1R) plays a crucial role in modulating various physiological functions and is considered an effective therapeutic target for osteoporosis. However, a lack of detailed molecular and energetic information about PTH1R limits our comprehensive understanding of its activation process. In this study, we performed computational simulations to explore key events in the activation process, such as conformational changes in PTH1R, Gs protein coupling, and the release of guanosine diphosphate (GDP).
View Article and Find Full Text PDFJ Spinal Cord Med
January 2025
Department of Rehabilitation Medicine, University of Washington, Seattle, Washington, USA.
Objective: To engage U.S. end users to (1) gather information on facilitators and barriers to awareness and adoption of the Canadian Spinal Cord Injury (SCI) Physical Activity (PA) guidelines; (2) inform potential adaptations to the presentation and messaging of the guidelines; and (3) develop recommendations for targeted dissemination strategies to promote awareness in the United States.
View Article and Find Full Text PDFChemistry
January 2025
Natinal Institute of Adavanced Industrial Science and Technology, Interdisciplinary Research Center for Catalytic Chemistry, Higashi 1-1-1, 305-8565, Tsukuba, JAPAN.
Unprecedented (2E,4E,6Z,8Z)-nona-2,4,6,8-tetraenoate derivatives highly substituted by aryl groups have been synthesized by the reaction of rhodium complexes having aryl-substituted hexa-1,3,5-trienyl ligands with acrylates. These compounds have potential axial chirality, and their enantiomers are isolable by the chiral HPLC technique. Although the racemization barrier of isolated enantiomers was not high, it was found that a cyclic dimer synthesized by head-to-tail transesterification of a modified analog has quite a stable axial chirality even at a high temperature.
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