Bogdan Florea

Prof. Dr. Bogdan Florea

University Politehnica of Bucharest, Bucharest, Bucureşti, Romania
orcid

Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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18 July 2024 in Polymers
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Journal Article
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Raluca SomoghiRaluca Somoghi
Raluca Somoghi
ASAugustin Semenescu
Augustin Semenescu
VPVili Pasare
Vili Pasare
COChivu Oana
Chivu Oana
NDNițoi Dan
Nițoi Dan
BFBogdan Florea
Bogdan Florea
Epoxy resins were reinforced with different ZnO nanofillers (commercial ZnO nanoparticles (ZnO NPs), recycled ZnO and functionalized ZnO NPs) in order to obtain ZnO–epoxy composites with suitable mechanical properties, high adhesion strength, and good resistance to corrosion. The final properties of ZnO–epoxy composites depend on several factors, such as the type and contents of nanofillers, the epoxy resin type, curing agent, and preparation methods. This paper aims to review the preparation methods, mechanical and anti-corrosion performance, and applications of ZnO–epoxy composites. The epoxy–ZnO composites are demonstrated to be valuable materials for a wide range of applications, including the development of anti-corrosion and UV-protective coatings, for adhesives and the chemical industry, or for use in building materials or electronics.

28 October 2022 in Crystals
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Journal Article
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DIDionisie Istrate
Dionisie Istrate
GSGabriela Sbarcea
Gabriela Sbarcea
ADAlin Mihai Demian
Alin Mihai Demian
ABAndreea Daniela Buzatu
Andreea Daniela Buzatu
LSLaura Salcianu
Laura Salcianu
BGBrandusa Ghiban
Brandusa Ghiban
The aluminum alloy type 5083, which has high corrosion resistance, excellent weldability, and good strength, is widely used in shipbuilding, automotive, aerospace, and industrial construction. The present paper has the aim of establishing a possible correlation between mechanical properties, structural characteristics, and cavitation erosion properties of the 5083 alloy after applying different heat treatments. Different homogenization heat treatments (350 °C, 450 °C) were applied, each followed by cooling in air and artificial aging at different temperature (140 °C and 180 °C) with three maintenance periods, 1 h, 12 h, and 24 h. The experiments concerning cavitation resistance of the experimental samples were completed in accordance with ASTM G32-2016. The cavitation erosion resistance were determined either by analytical diagrams MDER (or MDE) vs. cavity attack duration, or by measuring the maximum erosion attack by stereomicroscopy and scanning electron microscopy. Finally, the best combination of heat treatments applied to cast aluminum products type 5083 is homogenization at 350 °C followed by artificial aging at 180 °C, at which the highest mechanical characteristics are obtained, a resilience of 25 J/cm2, a grain size of 140–180 μm, and a maximum depth of the erosion MDEmax around 14–17 µm.

1 June 2023 in Metals
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DIDionisie Istrate
Dionisie Istrate
IBIlare Bordeasu
Ilare Bordeasu
BGBrandusa Ghiban
Brandusa Ghiban
Bogdan IstrateBogdan Istrate
Bogdan Istrate
GSGabriela Sbarcea
Gabriela Sbarcea
DGDinu-Valentin Gubencu
Dinu-Valentin Gubencu
The 5000 series aluminum alloy 5083 is distinguished by excellent processability, excellent welding characteristics, and a strong resilience to corrosion, particularly in maritime environments. It is employed in the manufacture of ships, automobiles, spacecraft, and industrial buildings. The goal of the current study is to determine whether there is any relationship between the mechanical properties, structural characteristics, and cavitation erosion properties of aluminum alloy 5083 in the H111 state (rolled from 454 °C to 399 °C and annealed at 343 °C by holding in cooled air), followed by artificial ageing at (180 °C) with three maintenance periods of 1 h, 12 h, and 24 h, and at (140 °C) with three maintenance periods of 1 h, 12 h, and 24 h. The cavitation resistance experiments of the experimental samples were performed in accordance with ASTM G32-2016. The resistance to cavitation erosion was determined by making mean erosion penetration rate (MDER) or mean depth of erosion (MDE) analytical diagrams according to the duration of the cavitation attack and by measuring the maximum depth of cavitation erosion in the samples analyzed by stereomicroscopy and scanning electron microscopy. Finally, a structural correlation between the condition of the artificially aged laminate alloy and its resistance to cavitation erosion could be achieved: ageing at 180 °C, maintained for 24 h, could lead to a maximum depth of cavitation erosion MDEmax of about 5 µm.

14 May 2025 in Crystals
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BGBrandusa Ghiban
Brandusa Ghiban
IBIlare Bordeasu
Ilare Bordeasu
AAAntoniac Aurora
Antoniac Aurora
Antoniac IulianAntoniac Iulian
Antoniac Iulian
CGCristina Gheorghe
Cristina Gheorghe
Anca Maria FratilaAnca Maria Fratila
Anca Maria Fratila
This paper presents the biodegradation and cavitational erosion behavior of new zinc alloys in the ZnMgFe system. The alloys were heat-treated through homogenization at 300 °C and 400 °C, with maintenance times of 5 and 10 h each. The experimental research consisted of characterizing the structure and mechanical properties of the newly made alloys in different structural states, as well as determining their biodegradation and cavitation behavior. Biodegradability was achieved using laboratory tests in SBF, with different immersion durations (3, 7, 14, 21, or 35 days). The cavitation behavior was assessed by performing tests on a piezoceramic crystal vibrator in compliance with ASTM G32-2016, thus constructing the curves of the erosion velocity MDER(t) and the cumulative average erosion depth MDE(t). The analyses performed on the mechanical properties, microscopic images, and the cavitation parameters MDER and MDEmax (results at the end of the cavitation attack) showed the effect of the heat treatments on the structure and structural resistance to cyclic loadings of the cavitation. The double alloying of zinc with magnesium and iron may increase either the mechanical properties or the corrosion resistance to cavitation and can control the biodegradability of the resulting ZnMgFe alloy. The best heat treatment for improving these properties is homogenization at 400 °C/10 h, which may increase the cavitation erosion of zinc by up to seven times. The experimental results demonstrate that the new alloys from the ZnMgFe system are a good option for manufacturing biodegradable implants with functional in vitro properties.

1 July 2025 in Proceedings of the International Conference on Business Excellence
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MIMonica Iorga
Monica Iorga
ASAugustin Semenescu
Augustin Semenescu
DMDragoș Florin Marcu
Dragoș Florin Marcu
BFBogdan Florea
Bogdan Florea
This study investigates the perception of the Romanian population regarding the Guarantee-Return System (GRS) using statistical analysis. We have used a structured questionnaire (both physically and electronically) to collect data from a representative sample of 604 respondents. The Chi-square statistical tests were used to evaluate the public acceptance and awareness of the system. Most of the respondents are receptive to GRS implementation, the questionnaire finds, citing key advantages such as increased recycling rates and environmental benefits. This study contributes to the existing literature on the matter by offering one of the first statistically representative assessments of the GRS in Romania. Potential biases in self-reported data and the focus on short-term perspectives might be included. The future research should explore the long-term impact of GRS on consumer behavior and economic sustainability. This paper aims to verify using statistical tools the research hypotheses regarding the perception of the Romanian population on the Guarantee-Refund System (GRS). The questionnaire aims to highlight the extent to which the Guarantee-Return System is known in Romania and the concrete way of achieving it optimally in the consumers’ view. The first stage of the research was aimed at establishing representative samples. The literature at the international and national levels is not very extensive, given the topic’s novelty. The questionnaire was applied both in physical format and by electronic means. The paper is one of the first statistically representative impact studies conducted in Romania regarding ways the population perceived the introduction of the Guarantee-Refund System.

28 March 2023 in ChemBioChem
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Journal Article
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TLTyrza van Leeuwen
Tyrza van Leeuwen
WDWard Doelman
Ward Doelman
RKRobin W. R. van Den Kieboom
Robin W. R. van Den Kieboom
BFBogdan Florea
Bogdan Florea
SKSander I. van Kasteren
Sander I. van Kasteren
Uptake and processing of antigens by antigen presenting cells (APCs) is a key step in the initiation of the adaptive immune response. Studying these processes is complex as the identification of low abundant exogenous antigens from complex cell extracts is difficult. Mass‐spectrometry based proteomics – the ideal analysis tool in this case – requires methods to retrieve such molecules with high efficiency and low background. Here, we present a method for the selective and sensitive enrichment of antigenic peptides from APCs using click‐antigens; antigenic proteins expressed with azidohomoalanine (Aha) in place of methionine residues. We here describe the capture of such antigens using a new covalent method namely, alkynyl functionalized PEG‐based Rink amide resin, that enables capture of click‐antigens via copper‐catalyzed azide‐alkyne [2 + 3] cycloaddition (CuAAC). The covalent nature of the thus formed linkage allows stringent washing to remove a‐specific background material, prior to retrieval peptides by acid‐mediated release. We successfully identified peptides from a tryptic digest of the full APC proteome containing femtomole amounts of Aha‐labelled antigen, making this a promising approach for clean and selective enrichment of rare bioorthogonally modified peptides from complex mixtures.