The intermediate state dependence of photoelectron circular dichroism (PECD) in resonance-enhanced multi-photon ionization of fenchone in the gas phase is experimentally studied. By scanning the excitation wavelength from 359 to 431 nm, we simultaneously excite up to three electronically distinct resonances. In the PECD experiment performed with a broadband femtosecond laser, their respective contributions to the photoelectron spectrum can be resolved. High-resolution spectroscopy allows us to identify two of the resonances as belonging to the B- and C-bands, which involve excitation to states with 3s and 3p Rydberg character, respectively. We observe a sign change in the PECD signal, depending on which electronic state is used as an intermediate, and are able to identify two differently behaving contributions within the C-band. Scanning the laser wavelength reveals a decrease of PECD magnitude with increasing photoelectron energy for the 3s state. Combining the results of high-resolution spectroscopy and femtosecond experiment, the adiabatic ionization potential of fenchone is determined to be IP=(8.49±0.06) eV.
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http://dx.doi.org/10.1063/1.4982614 | DOI Listing |
Sci Rep
December 2024
Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital and Shenzhen Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Shenzhen, 518116, Guangdong, China.
This study aimed to find a safe and effective cumulative cisplatin dose (CCD) for concurrent chemoradiotherapy (CCRT) beneficiaries among elderly nasopharyngeal carcinoma (NPC) patients. A total of 765 elderly (≥ 60 years old) NPC patients treated with cisplatin-based CCRT and IMRT-alone from 2007 to 2018 were included in this study. RPA-generated risk stratification was used to identify CCRT beneficiaries.
View Article and Find Full Text PDFJ Hazard Mater
December 2024
State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China.
Global concern over per- and polyfluoroalkyl substances (PFASs), especially perfluorooctane sulfonate (PFOS), disposal prompts the search for effective degradation methods. Subcritical water hydrothermal treatment shows promise but suffers from unclear degradation pathways, hindering engineering application design due to unknown intermediate products. This study introduces Fe-based amorphous alloy to enhance the subcritical water hydrothermal degradation of PFOS, achieving a degradation rate of approximately 85 % under optimized conditions of 325 °C and 1 M sodium bicarbonate (NaHCO₃), compared to 56 % without the alloy.
View Article and Find Full Text PDFAm J Emerg Med
December 2024
Department of Emergency Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA; Department of Epidemiology and Prevention, Wake Forest School of Medicine, Winston-Salem, NC, USA; Department of Implementation Science, Wake Forest School of Medicine, Winston-Salem, NC, USA.
Introduction: The History, Electrocardiogram, and Troponin (HET) score is a simplified alternative to the HEART score for risk stratifying emergency department (ED) patients with chest pain. This study evaluates the safety and efficacy of the HET score for 30-day cardiac death or myocardial infarction (MI).
Methods: We conducted a secondary analysis of the STOP-CP multisite cohort study.
J Am Chem Soc
December 2024
Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States.
Designing catalysts with well-defined active sites with chemical functionality responsive to visible light has significant potential for overcoming scaling relations limiting chemical reactions over heterogeneous catalyst surfaces. Visible light can be leveraged to facilitate the removal of strongly bound species from well-defined single cationic sites (Rh) under mild conditions (323 K) when they are incorporated within a photoactive perovskite oxide (Rh-doped SrTiO). CO, a key intermediate in many chemistries, forms stable geminal dicarbonyl Rh complexes (Rh(CO)), that could act as site blockers or poisons during a catalytic cycle.
View Article and Find Full Text PDFACS Appl Mater Interfaces
December 2024
Institute of Chemistry, Federal University of Mato Grosso do Sul, Avenida Senador Filinto Muller 1555, Campo Grande, Mato Grosso do Sul 79074-460, Brazil.
There has been huge interest among chemical scientists in the electrochemical reduction of nitrate (NO) to ammonia (NH) due to the useful application of NH in nitrogen fertilizers and fuel. To conduct such a complex reduction reaction, which involves eight electrons and eight protons, one needs to develop high-performance (and stable) electrocatalysts that favor the formation of reaction intermediates that are selective toward ammonia production. In the present study, we developed and applied CoO/graphene nanoribbon (GNR) electrocatalysts with excellent properties for the effective reduction of NO to NH, where NH yield rate of 42.
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