The initial oxidation process of the ultraclean Si(001)-c(4x2) surface is studied using scanning tunneling microscopy at low temperature. At the early stage of oxygen adsorption, reactions with Si atoms at SB steps are dominant over those at terraces by more than 2 orders of magnitude, and they proceed in two distinct stages to high oxidation states. Guided by the ab initio calculations, the oxidation structures at each stage are proposed. The extreme reactivity of the step edge is due to the presence of rebonded adatoms with dangling bonds and weak rebonds, and their proximity allows the formation of -Si-O- chain structures along the step edge, unlike those on the Si(111) surface.
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http://dx.doi.org/10.1103/PhysRevLett.97.036103 | DOI Listing |
Nat Commun
January 2025
Beijing Advanced Innovation Center for Integrated Circuits, School of Integrated Circuits, Peking University, Beijing, China.
Compute-in-memory based on resistive random-access memory has emerged as a promising technology for accelerating neural networks on edge devices. It can reduce frequent data transfers and improve energy efficiency. However, the nonvolatile nature of resistive memory raises concerns that stored weights can be easily extracted during computation.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
Department of Applied Biology, Faculty of Textile Science and Technology, Shinshu University, Ueda 386-8567, Nagano, Japan.
Osteocalcin is a useful biomarker for bone formation and bone-related diseases. KTM219 is an anti-osteocalcin C-terminal peptide antibody. The single-chain variable region (scFv) and antigen-binding fragment (Fab) of KTM219 are applicable to the Quenchbody (Q-body) immunoassay.
View Article and Find Full Text PDFAnimals (Basel)
January 2025
CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization, Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610213, China.
The genus Mittleman, 1950, belonging to the family Scincidae, exhibits considerable morphological convergence, complicating species delimitation and resulting in underestimated diversity. Currently, 41 species are formally recognized in this genus, although this figure likely underestimates its true richness. In this study, a new species of the genus , , is described from urban and suburban areas of Chengdu, Sichuan Province, Southwest China.
View Article and Find Full Text PDFDiagnostics (Basel)
January 2025
Department of Medical Device and Healthcare, Dongguk University, Seoul 04620, Republic of Korea.
Liver cancer has a high mortality rate worldwide, and clinicians segment liver vessels in CT images before surgical procedures. However, liver vessels have a complex structure, and the segmentation process is conducted manually, so it is time-consuming and labor-intensive. Consequently, it would be extremely useful to develop a deep learning-based automatic liver vessel segmentation method.
View Article and Find Full Text PDFJ Environ Sci (China)
July 2025
Department F.-A. Forel, University of Geneva, Boulevard Carl-Vogt 66, CH-1205 Geneva, Switzerland. Electronic address:
We identified the antimony species present in a wide variety of plastic samples by X ray absorption spectroscopy (XAS) at the Sb L-edge. The samples contained different concentrations of antimony (Sb), ranging from PET bottles in which Sb compounds are used as catalysts, with concentrations around 300 mg/kg, to electrical equipment in which the element is used as a flame retardant, with concentrations of several tens of thousands of mg/kg. Although the shape of the spectra at the L-edge is quite similar for all Sb reference materials, we were able to identify antimony glycolate or acetate in PET bottles, bound organic Sb in c-PET trays and senarmontite in electrical materials as the main Sb components.
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