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原子与分子物理学报 2025年 34-38页

作者：史金磊陈莉莉李依陈卫光姜广智郑州师范学院物理与电子工程学院郑州市低维纳米材料重点实验室

基于密度泛函理论的第一性原理计算方法,研究了O2在五边形B2c上的吸附与解离动力学行为.研究结果表明,五边形B2c可以有效地激发O2.然而,形成的O2吸附结构却很容易发生解离,反应过程仅需克服约0.10 eV的势垒.有意思的是,O2解离后形成的O... 详细信息

基于密度泛函理论的第一性原理计算方法,研究了O2在五边形B2c上的吸附与解离动力学行为.研究结果表明,五边形B2c可以有效地激发O2.然而,形成的O2吸附结构却很容易发生解离,反应过程仅需克服约0.10 eV的势垒.有意思的是,O2解离后形成的O*表面结构却能使后续吸附的O2自发解离,解离反应伴随着衬底结构的B-B键的破坏,使其在空气中难以稳定存在.

关键词：五边形B c O 吸附与解离第一性原理计算

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Integrated filler metal/base metal manufacturing via cold spray additive manufacturing for brazing c f /Sic and superalloy

Transactions of Materials Research

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Transactions of Materials Research 2025年第1期1卷

作者： Pengcheng Wang Weihan Liu Lei Gu Hao Ran Xiaoguo Song Zhaoyi Pan Haiyan chen Wenya Li State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Friction Welding Technologies Northwestern Polytechnical University Xi'an 710072 China State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology Harbin 150001 China Xi'an Space Engine Company Limited Xi'an 710072 China

A new integrated filler metal/base metal manufacturing method by cold spray additive manufacturing is proposed. The integrated cuTi filler metal/GH3536 and cuTi + W composite filler metal/GH3536 are prepared by cold spray additive manufacturing techniques. The large plastic deformation of cu and Ti particles and the tamping effect of W particles promote the interfacial bonding of particles, which improves the weldability of cold sprayed cuTi + W composite filler metals. Based on the cold sprayed cuTi + W composite filler metal, the c f /Sic composites and GH3536 are successfully brazed, and the typical microstructure and brazing mechanism are investigated. As a result, the shear strength of c f /Sic-GH3536 joint brazed by cold sprayed cuTi + W composite filler metal reaches 77 MPa. This study highlightes the great potential of cold spray additive manufacturing for integrated filler metal/base metal manufacturing in brazing.

关键词： Brazing cold spray additive manufacturing composite filler Interface reaction c f /Sic composite

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characterization of the interaction between human cytochrome c and transfer RNA phe

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Magnetic Resonance Letters 2025年

作者： Guangqing Zhang Jianhua Zhan Xin chai Bin Jiang Maili Liu Xu Zhang Danyun Zeng Key Laboratory of Magnetic Resonance in Biological Systems State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics National Center for Magnetic Resonance in Wuhan Innovation Academy for Precision Measurement of Science and Technology Chinese Academy of Sciences Wuhan 430071 China University of Chinese Academy of Sciences Beijing 100049 China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Wuhan 430074 China Optics Valley Laboratory Wuhan 430074 China

cytochrome c (cyt c ) is released from mitochondria into the cytosol upon apoptotic stimulation, ultimately triggering programmed cell death. Recent studies have revealed that transfer RNA (tRNA) interacts with cyt c , impeding the formation of the apoptosome complex and thereby suppressing apoptosis. To elucidate the molecular mechanism underlying the interaction between cyt c and tRNA, nuclear magnetic resonance (NMR)-based chemical shift perturbation and intensity analysis were employed to characterize the binding interface between cyt c and tRNA phe . The findings demonstrate that cyt c primarily engages with tRNA phe through its 70-85 Ω-loop and N-terminal α-helix. This interaction sterically hinders the accessibility of small molecules, such as H 2 O 2 , to the hydrophobic pocket of cyt c , consequently attenuating its peroxidase activity. Furthermore, oxidative modification of cyt c , particularly the carbonylation of positively charged lysine residues, weakens this interaction.

关键词： interaction NMR cytochrome c tRNA oxidative modification

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From phytotoxicity to growth stimulation: contrasting effects of Ti 3 c 2 T x MXene and MoAlB@MBene on higher plants

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Journal of Environmental chemical Engineering 2025年第3期13卷

作者： Michał Jakubczak Dominika Bury Dorota Moszczyńska Michael Naguib Agnieszka M. Jastrzębska Faculty of Mechatronics Warsaw University of Technology św. Andrzeja Boboli 8 Warsaw 02-525 Poland Faculty of Materials Science and Engineering Warsaw University of Technology Wołoska 141 Warsaw 02-507 Poland Department of Physics and Engineering Physics Tulane University New Orleans LA 70118 USA Department of Chemistry Tulane University New Orleans LA 70118 USA

Novel 2D nanomaterials offer the potential in addressing environmental challenges such as pollution and waste management, water scarcity, and agricultural limitations. While their catalytic and oxidative properties aid pollutant degradation, carbon sequestration, water treatment, and crop improvement, thorough phytotoxicity evaluation is necessary before application. In our study, we developed Ti 3 c 2 T x MXene and MoAlB@MBene, each showcasing unique structures and chemistries. DLS, zeta potential, and EDS analyses elucidated their size distribution, stability, and elemental composition. XRD confirmed efficient MAX into MXene transformation and MBene’s single-phase nature, while FT-IR suggested relatively pure surface chemistries. UV-Vis spectroscopy revealed plasmonic peaks for MXene, and UV absorption edge for MBene. To assess biological impact, we conducted a phytotoxicity evaluation based on germination efficiency, root and shoot elongation, biomass accumulation, and chlorophyll quantitative and qualitative studies. Ecotoxicity assessments on higher plants revealed MXene's concentration-dependent phytotoxicity, in contrast to growth-promoting MBene. Microscopic observations detailed MXene-induced root meristem disruptions, while MBene stimulated lateral root growth. Mass analyses demonstrated MXene-induced dry mass increases, even by 22 % at 1000 mg dm −3 , relative to the control, contrasting with MBene’s vitality preservation and the carbon cycle. chlorophyll and its fluorescence studies revealed MXene-induced stress, whereas MBene exhibited positive or neutral. crucially, XRF analysis suggested limited nanomaterial uptake by plants. Altogether, our study introduces a novel approach to evaluating 2D nanomaterials' phytotoxicity, emphasizing the need to understand potential risks before application. While these materials offer environmental benefits, our findings show that careful evaluation is key to ensuring safe and sustainable use in real-world scenario. S

关键词： Ti 3 c 2 T x MXene MoAlB@MBene Phytotoxicity Germination Lepidium sativum Sinapis alba Sorghum saccharatum

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Sources and fate of dissolved sulphate, carbonate, and nitrate in groundwater of the temperate climate zone: a high-resolution multi-isotope (H, c, O, S) study in north-eastern Germany**

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Isotopenpraxis Isotopes in Environmental and Health Studies 2025年第1期61卷

作者： Anna-Kathrina Jenner christoph Malik Gerd Böttcher Patricia Roeser Matthias Gehre Iris Schmiedinger Michael Ernst Böttcher a Geochemistry & Isotope Biogeochemistry Leibniz Institute for Baltic Sea Research (IOW) Warnemünde Germany a Geochemistry & Isotope Biogeochemistry Leibniz Institute for Baltic Sea Research (IOW) Warnemünde Germanyb Institute for Geography and Geology University of Greifswald Greifswald Germanyc Department of Hydrogeology UmweltPlan GmbH Stralsund Stralsund Germany d Landesamt für Umwelt Naturschutz und Geologie (LUNG) Güstrow Germany e Department Technical Biogeochemistry Helmholtz Centre for Environmental Research- UFZ Leipzig Germany a Geochemistry & Isotope Biogeochemistry Leibniz Institute for Baltic Sea Research (IOW) Warnemünde Germanyb Institute for Geography and Geology University of Greifswald Greifswald Germanyf Interdisciplinary Faculty University of Rostock Rostock Germany

ABSTRAcTDifferent natural and anthropogenic drivers impact the groundwater in the catchment area of the southern Baltic Sea, north-eastern Germany. To understand the sources and fate of dissolved sulphate, carbonate, and nitrate on a regional scale, in the present study, the hydrogeochemical and multi-stable isotope (H, c, O, S) composition of groundwater samples from up to more than 300 sites (depths from near-surface down to 291 m) was studied. To investigate the element sources and the water–rock–microbe interaction processes that took place along the groundwater flow path, a mass balance approach is combined with physico-chemical modelling. Microbial oxidation of pyrite using nitrate as electron acceptor and a superimposition by dissimilatory sulphate reduction at depth is shown in a drilled vertical profile at one site. This trend frames the behaviour of sulphate at many investigated groundwater wells. Dissolved inorganic carbon (DIc) in the groundwater was found to be controlled by the uptake of biogenic carbon dioxide, the dissolution of carbonate minerals, thein situoxidation of DOc and, at a few sites, the formation and/or oxidation of biogenic methane. Enhanced groundwater DIc loads may potentially increase future cO2degassing to the atmosphere upon release of groundwaters to the surface. These results form a comprehensive base for understanding the present situation and for future investigations.

关键词： Groundwater spring water hydro-biogeochemistry stable isotopes (H c O S) sources of carbonate sulphate and nitrate denitrification pyrite oxidation microbial sulphate reduction Southern Baltic Sea North-eastern Germany

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MARVEL analysis of high-resolution rovibrational spectra of 17O13c18O and 17O13c17O

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Journal of Quantitative Spectroscopy and Radiative Transfer 2025年 343卷

作者： Azzam, Ala'a A.A. AlAlawin, Joud M.A. Tennyson, Jonathan Furtenbacher, Tibor császár, Attila G. Research Department AstroJo Institute Wasfi Al-Tal St Amman Jordan Department of Physics The University of Jordan Queen Rania St Amman Jordan Department of Physics and Astronomy University College London Gower Street LondonWC1E 6BT United Kingdom ELTE Eötvös Loránd University Institute of Chemistry Pázmány Péter sétány 1/A BudapestH-1117 Hungary

Spectroscopic networks, based on rovibrational line-center measurements found in 10/5 literature sources, are presented for the triply substituted carbon dioxide isotopologues 17O13c18O/17O13c17O (738/737, according to a well-established shorthand notation followed in this study). For 738/737, the spectroscopic networks contain 2058(1488)/1831(1349) measured(unique) transitions, belonging to 25/22 vibrational bands. The transitions collected for 738 and 737 span the wavenumber regions 623−7888 and 624−6739cm−1, respectively. These spectroscopic networks determine 945 and 877 empirical rovibrational energy levels for 738 and 737, respectively, extracted with the help of the MARVEL (Measured Active Rotational–Vibrational Energy Levels) protocol and code. The energy levels of 738/737 span the range of 0−8762/0−7201hccm−1 and the polyads from 0 to 11 for 738 and from 0 to 10 for 737. A detailed comparison of the empirical rovibrational energy levels of this study with their counterparts in two published databases, cDSD-296, and Ames-2021, shows very good overall agreement. © 2025 The Author(s)

关键词： Rovibrational energy levels cO 2 17 O 13 c 18 O 17 O 13 c 17 O Line positions Transitions MARVEL

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Photocatalytic coupling of N-Heteroarenes and Alkanes/Ethers with ce-Doped g-c3N4 and Bu4Ncl

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Synfacts 2025年第3期21卷 281-281页

作者： Yasuhiro Uozumi Kenji Tsukamoto

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Norm upper-semicontinuity of functions supported on open abelian isotropy in étale groupoids. corrigendum to “Reconstruction of groupoids and c ⁎ -rigidity of dynamical systems” [Adv. Math. 390 (2021) 107923]

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Advances in Mathematics 2025年 466卷

作者： Toke Meier carlsen Anna Duwenig Efren Ruiz Aidan Sims Køge Denmark Department of Mathematics KU Leuven Leuven Belgium Department of Mathematics University of Hawaii Hilo 200 W. Kawili St. Hilo HI 96720-4091 USA School of Mathematics and Applied Statistics University of Wollongong NSW 2522 Australia

We consider étale Hausdorff groupoids in which the interior of the isotropy is abelian. We prove that the norms of the images under regular representations, of elements of the reduced groupoid c ⁎ -algebra whose ... 详细信息

关键词： primary 46L05 Groupoid c ⁎ -algebra cartan subalgebra

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Evaluation of dose-linearity in the systemic availability and pharmacokinetics of topically administered diclofenac: a 14 c-microdosing study in healthy volunteers

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Drug Metabolism and Disposition 2025年

作者： Severin Mairinger Mihye Kwon Martin Bauer Jinho Song Edith Lackner Anselm Jorda Felix Bergmann Iris K. Minichmayr Ka Yeon Kim Min Sun choi Jae Hoon Shim Stephen R. Dueker Markus Zeitlinger Oliver Langer Department of Clinical Pharmacology Medical University of Vienna 1090 Vienna Austria Department of Biomedical Imaging and Image-guided Therapy Medical University of Vienna 1090 Vienna Austria Korea Radio-Isotope Center for Pharmaceuticals Korea Institute of Radiological & Medical Sciences 01812 Seoul Korea

An important safety consideration for topically administered drugs is the extent of systemic exposure they achieve. The aim of this study was to evaluate whether a topically administered microdose of the model drug diclofenac can predict the systemic availability, plasma, and tissue pharmacokinetics of a topical therapeutic dose. Eight healthy participants (6 men, 2 women) participated in a four-period, cross-over study. In period 1, a topical microdose (62±6 μg) was administered; in period 2, a single intravenous microdose (0.95±0.03 μg); in period 3, a topical therapeutic dose (120 mg); and in period 4, a single intravenous therapeutic dose (75 mg) of [ 14 c]diclofenac, with or without the addition of unlabeled diclofenac. Venous blood, urine, and microdialysis samples from subcutaneous adipose tissue beneath the dermal application site were collected for 24 hours post-dosing. Total 14 c-concentrations in plasma and microdialysates were quantified using accelerator mass spectrometry (AMS). The disposition of intravenously administered [ 14 c]diclofenac was dose-linear. However, after topical administration, the fraction of total 14 c absorbed (geometric mean, 95% cI) was higher ( P =0.0019, two-tailed, paired t -test) for the microdose (0.48%, 0.34-0.67%) compared to the therapeutic dose (0.13%, 0.07-0.22%) (geometric mean ratio, 90% cI: 3.79, 2.41-5.98). Dose-normalized 14 c-concentrations in microdialysates were low, variable, and did not differ between doses. Our study demonstrates the feasibility of quantifying 14 c-concentrations in plasma and microdialysates following the topical administration of a microdose of [ 14 c]diclofenac. The observed non-linearity in systemic availability after topical dosing suggests that microdosing may not accurately predict the disposition of certain topical drugs at therapeutic doses. Significance Statement We assessed whether a topically applied microdose of diclofenac could predict the systemic availability of a therapeutic

关键词： Microdosing Topical drugs Microdialysis Dose-linearity ABc adenosine triphosphate-binding cassette ADME absorption distribution metabolism and excretion AUc 0-24 area under the concentration-time curve from 0 to 24 hours AUc 0-inf area under the concentration-time curve from 0 to infinity AMS accelerator mass spectrometry BcRP breast cancer resistance protein 14 c carbon-14 cI confidence interval cL total clearance from plasma c max maximum plasma concentration F abs fraction absorbed GMR geometric mean ratio HSA human serum albumin Lc-MS/MS liquid chromatography tandem mass spectrometry LLOQ lower limit of quantification LSc liquid scintillation counting MRT mean residence time ng-eg/mL nanogram diclofenac equivalents per milliliter NSAID nonsteroidal anti-inflammatory drug PBS phosphate-buffered saline PET positron emission tomography P-gp P-glycoprotein PK pharmacokinetic(s) t max time to maximum plasma concentration V z volume of distribution V ss volume of distribution at steady state

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Radical dehydroxylative c -glycosylation of 1-hydroxycarbohydrates enabled by photoredox catalysis

Green Synthesis and Catalysis

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Green Synthesis and catalysis 2025年

作者： Wenyan Shi Xingxiu Yan Wuyin Wang Zhijun Sun Hong Yi Aiwen Lei College of Chemistry and Molecular Sciences Wuhan University Wuhan 430072 Hubei China The Institute for Advanced Studies (IAS) Wuhan University Wuhan 430072 Hubei China State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Minis-try of Education Wuhan 430072 Hubei China Hubei Key Laboratory of Stomatology School & Hospital of Stomatology Frontier Science Center for Immunology and Metabolism Wuhan University Wuhan 430072 Hubei China

c -Glycosides, known for their superior in vivo stability compared to their O - and N -glycoside counterparts, have been widely explored as drug candidates and utilized in biological research. Traditional radical c-glycosidation techniques have relied on precursors such as glycosyl halides and glycosyl sulfones. These methods, however, face several challenges, including the instability of glycosyl precursors, the requirement for multi-step synthesis, and limited practicality. Herein, we present a straightforward, metal-free method to synthesize both sp 2 and sp 3 c-glycosides with high stereoselectivity via direct deoxy-glycosidation of readily available and stable 1-hydroxycarbohydrates. Mechanistic investigations indicate the involvement of glycosyl radicals in the reaction. cellular assays reveal the antitumor activity of the synthesized products, which underscores the potential of this strategy in medicinal chemistry.

关键词： Deoxyfunctionalization NHc c -glycosides carbohydrates Photoredox

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