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The possibility of removing metallic (such as Zr, Fe, Cr, and Zn) impurities and non-metallic (such as [O] and C) impurities from technogenic hafnium through single and double refining in the conditions of electron beam melting (EBM) has been studied. The influence of thermodynamic and kinetic parameters on the degree of removal of these impurities from the base metal under vacuum conditions and within a temperature interval of 2500 K to 3100 K is defined. The relative volatility of metal impurities and the stability of the oxides and carbides present in the base metal are evaluated. The possibility for complete removal of Fe, Cr, Zn, [O], and C during EBM is shown. In the case of double refining, at a temperature of 2700 K for 20 min, the maximum degree of removal of Zr is 46.8%, the achieved highest hafnium purity is 99.004%, and the overall effectiveness of the refining of hafnium from impurities is 53%. There is a correlation between the degree of removal of Zr and the micro-hardness of the Hf ingots obtained after EBM. The weight losses vary in the ranges of 1.5-5.8% and 1-8% under the studied single and double refining processes, respectively.
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http://dx.doi.org/10.3390/ma15238518 | DOI Listing |
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State Key Laboratory of Green Chemical Engineering and Industrial Catalysis, Center for Computational Chemistry and Research Institute of Industrial Catalysis, East China University of Science and Technology, Shanghai 200237, People's Republic of China.
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The escalating cancer burden in Sub-Saharan Africa (SSA), with projected doubling of incidence and mortality by 2040, necessitates innovative, cost-effective strategies for prevention, diagnosis, and treatment. While known infectious triggers like HPV, hepatitis viruses, and account for an estimated 28.7% of cancers in SSA, the full scope of microbially-mediated oncogenesis remains underexplored.
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UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, Caparica, Portugal; Associate Laboratory i4HB - Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, Caparica, Portugal. Electroni
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CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
African swine fever (ASF) has caused a devastating pandemic among domestic and wild swine, leading to significant economic losses in the global swine industry. Recombinant live-attenuated vaccines are a potential option for the control of ASF. However, safe and effective vaccines against the ASF virus (ASFV) are not yet commercially available, and thus, additional vaccine candidates still need to be developed.
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Department of Field Crops, Faculty of Agriculture, University Ege, 35100, İzmir, Turkey.
Fennel (Foeniculum vulgare Mill.) is a widely cultivated medicinal and aromatic plant valued for its essential oils used in pharmaceutical, culinary, and industrial applications. Breeding activities for fennel have been historically limited, but recent genomic advances have revealed substantial genetic diversity and variability among its populations, offering new opportunities to improve yield, oil composition, and stress resilience.
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