The presence of uranium, with a bulk mass fraction of about 1.5 wt% and radiolytic alterations are a feature of Cenomanian amber from Křižany, at the northeastern edge of the North Bohemian Cretaceous uranium ore district. Pores and microcracks in the amber were filled with a mineral admixture, mainly in the form of Zr-Y-REE enriched uraninite. As a result of radiolytic alterations due to the presence of uranium, structural changes were observed in the Křižany amber in comparison with a reference amber from Nové Strašecí in central Bohemia; this was of similar age and botanical origin but did not contain elevated levels of uranium. Structural changes involved an increase in aromaticity due to dehydroaromatization of aliphatic cyclic hydrocarbons, loss of oxygen functional groups, an increase in the degree of polymerization, crosslinking of CC bonds, formation of a three-dimensional hydrocarbon network in the bulk organic matrix, and carbonization of the organic matrix around the uraninite infill.
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http://dx.doi.org/10.1016/j.jenvrad.2016.04.004 | DOI Listing |
Nanotechnology
January 2025
Kwangwoon University, 20 Kwangwoonro Nowon-Gu Seoul, Nowon-gu, 01897, Korea (the Republic of).
To implement a neuromorphic computing system capable of efficiently processing vast amounts of unstructured data, a significant number of synapse and neuron devices are needed, resulting in increased area demands. Therefore, we developed a nanoscale vertically structured synapse device that supports high-density integration. To realize this synapse device, the interface effects between the resistive switching layer and the electrode were investigated and utilized.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing 102206, China.
Polymer-based dielectric films are increasingly demanded for devices under high electric fields used in new energy vehicles, photovoltaic grid connections, oil and gas exploration, and aerospace. However, leakage current is one of the significant factors limiting the improvement of the insulation performance. This paper tested the leakage current and condensed state structure characteristics of biaxially oriented polypropylene (BOPP) films and obtained the nonlinear characteristics of leakage current of BOPP films in the range of 40-440 V/μm and 40-110 °C.
View Article and Find Full Text PDFShock
January 2025
Department of Biomedical Engineering, Rutgers University, Piscataway, NJ 599 Taylor Road, Room 209, Piscataway, NJ, USA 08854.
Introduction: Coagulopathy following traumatic injury impairs stable blood clot formation and exacerbates mortality from hemorrhage. Understanding how these alterations impact blood clot stability is critical to improving resuscitation. Furthermore, the incorporation of machine learning algorithms to assess clinical markers, coagulation assays and biochemical assays allows us to define the contributions of these factors to mortality.
View Article and Find Full Text PDFActa Crystallogr B Struct Sci Cryst Eng Mater
February 2025
Novosibirsk State University, Pirogova 1, Novosibirsk 630090, Russian Federation.
High-pressure and low-temperature structural changes in the ferroelectric phase of (R)-3-quinuclidinol are analysed. The changes in unit-cell volume and parameters are continuous both on cooling and under increasing pressure. The anisotropy of the structural strain, however, is found to be different.
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