The aim of this work is to analyze the interactions of 5MeV electron beam radiation and a 290MeV/u Carbon beam with calcium carbonate (powder) at 298K and at different irradiation doses, for the potential use of calcium carbonate as a high-dose dosimeter. The irradiation doses with the electron beam were from 0.015 to 9MGy, and with Carbon beam from 1.5kGy to 8kGy. High-energy radiation induces the formation of free radicals in solid calcium carbonate that can be detected and measured by electron paramagnetic resonance (EPR). An increase of the EPR response for some of the free radicals produced in the sample was observed as a function of the irradiation dose. These measurements are reproducible; the preparation of the sample is simple and inexpensive; and the signal is stable for several months. The response curves show that the dosimeter tends to saturate at 10MGy. Based on these properties, we propose this chemical compound as a high-dose dosimeter, mainly for electron irradiation.
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http://dx.doi.org/10.1016/j.apradiso.2014.11.024 | DOI Listing |
Curr Microbiol
January 2025
Department of Microbiology and Immunology, Faculty of Pharmacy, Ain Shams University, Cairo, 11566, Egypt.
Fortimicins (FTMs) are fortamine-containing aminoglycoside antibiotics (AGAs) produced by M. olivasterospora DSM 43868 with excellent bactericidal activities against a wide range of Enterobacteriaceae and synergistic activity against multidrug-resistant (MDR) pathogens. Fortimicin-A (FTM-A), the most active member of FTMs, has the lowest susceptibility to inactivation by the aminoglycoside modifying enzymes (AMEs).
View Article and Find Full Text PDFEur J Dent
December 2024
Postgraduate Program of Conservative Dentistry Specialist, Faculty of Dental Medicine, Universitas Airlangga, Surabaya, Indonesia.
Objectives: Calcium carbonate (CaCO), a major inorganic component in bones and teeth, offers potential protection against demineralization. This study investigates the effect of CaCO from shells on the expression of fibroblast growth factor 2 (FGF2), transforming growth factor-β1 (TGF-β1), and collagen type 1 in the rat dental pulp.
Materials And Methods: The first maxillary molars of were perforated and subsequently pulp capped with CaCO extracted from shells.
Sci Rep
January 2025
Guangxi Academy of Sciences, Nanning, 530000, People's Republic of China.
It is essential to understand the modification mechanism of hydrophobicity nano-CaCO to their potential application in different fields of chemistry. However, the water absorption of hydrophobicity nano-CaCO is seldom studied. In this study, Raman, BET and TGA experiments were performed on nano-CaCO samples to obtain surfactants contents and microstructure characteristics.
View Article and Find Full Text PDFSci Rep
January 2025
Ali I. Al-Naimi Petroleum Engineering Research Center, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.
Microbial impacts on early carbonate diagenesis, particularly the formation of Mg-carbonates at low temperatures, have long eluded scientists. Our breakthrough laboratory experiments with two species of halophilic aerobic bacteria and marine carbonate grains reveal that these bacteria created a distinctive protodolomite (disordered dolomite) rim around the grains. Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) confirmed the protodolomite formation, while solid-state nuclear magnetic resonance (NMR) revealed bacterial interactions with carboxylated organic matter, such as extracellular polymeric substances (EPS).
View Article and Find Full Text PDFSci Rep
January 2025
Department of Dental Biomaterials Science, Dental Research Institute, School of Dentistry, Seoul National University, 101 Daehak-ro, Jongno-gu, Seoul, 03080, South Korea.
This study aimed to evaluate the effects of nanoparticulate CaCO (NPCC) on the biological properties of calcium silicate-based cements (CSCs), including their cytotoxicity, in vitro osteogenic activity, and interactions with rat femur tissue. The average size of NPCC was 90.3±26.
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