Bogdan Gheorghe Pulpea

Dr. Bogdan Gheorghe Pulpea

orcid

Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

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

Representative Publications

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15 December 2022 in Materials
Verified
Journal Article
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TRTraian Rotariu
Traian Rotariu
BPBogdan Gheorghe Pulpea
Bogdan Gheorghe Pulpea
FDFlorin-Marian Dirloman
Florin-Marian Dirloman
Aurel DiaconAurel Diacon
Aurel Diacon
Edina RusenEdina Rusen
Edina Rusen
RBRăzvan Horia Botiș
Răzvan Horia Botiș
The environmental impact and availability of ingredients are vital for the new generation of rocket propellants. In this context, several novel composite propellants were prepared based on the “greener” oxidizer phase-stabilized ammonium nitrate (PSAN), a micronized aluminum–magnesium alloy fuel, iron oxide powder burn rate modifier, triethylene glycol dinitrate (TEGDN) energetic plasticizer and a polyurethane (PU) binder. The novelty of this study is brought by the innovative procedure of synthesizing and combining the constituents of these heterogeneous compositions to obtain high-performance “eco-friendly” rocket propellants. The polymorphism shortcomings brought by ammonium nitrate in these energetic formulations have been solved by its co-crystallization with potassium salts (potassium nitrate, potassium chromate, potassium dichromate, potassium sulphate, potassium chlorate and potassium perchlorate). Polyester–polyol blends, resulting from recycled post-consumer polyethylene terephthalate (PET) glycolysis, were utilized for the synthesis of the polyurethane binder, especially designed for this type of application. To adjust the energetic output and tailor the mechanical properties of the propellant, the energetic plasticizer TEGDN was also involved. The performance and safety characteristics of the novel composites were evaluated through various analytical techniques (TGA, DTA, XRD) and specific tests (rate of combustion, heat of combustion, specific volume, chemical stability, sensitivity to thermal, impact and friction stimuli), according to NATO standards, providing promising preliminary results for further ballistics investigations.

30 November 2021 in Polymers
Verified
Journal Article
Open access
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Gabriela ToaderGabriela Toader
Gabriela Toader
PDPulpea Daniela
Pulpea Daniela
TRTraian Rotariu
Traian Rotariu
Aurel DiaconAurel Diacon
Aurel Diacon
Edina RusenEdina Rusen
Edina Rusen
Lucia LeonatLucia Leonat
Lucia Leonat
The issue of heavy metal and radionuclide contamination is still causing a great deal of concern worldwide for environmental protection and industrial sites remediation. Various techniques have been developed for surface decontamination aiming for high decontamination factors (DF) and minimal environmental impact, but strippable polymeric nanocomposite coatings are some of the best candidates in this area. In this study, novel strippable coatings for heavy metal and radionuclides decontamination were developed based on the film-forming ability of polyvinyl alcohol, with the remarkable metal retention capacity of bentonite nanoclay, together with the chelating ability of sodium alginate and with “new-generation” “green” complexing agents: iminodisuccinic acid (IDS) and 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTC). These environmentally friendly water-based decontamination solutions are capable of generating strippable polymeric films with optimized mechanical and thermal properties while exhibiting high decontamination efficiency (DF ≈ 95–98% for heavy metals tested on glass surface and DF ≈ 91–97% for radionuclides 241Am, 90Sr-Y and 137Cs on metal, painted metal, plastic, and glass surfaces).

15 December 2022 in Applied Sciences
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Journal Article
Open access
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BPBogdan Gheorghe Pulpea
Bogdan Gheorghe Pulpea
PDPulpea Daniela
Pulpea Daniela
ETEugen Trana
Eugen Trana
TRTraian Rotariu
Traian Rotariu
RGRaluca Elena Ginghina
Raluca Elena Ginghina
FDFlorin-Marian Dirloman
Florin-Marian Dirloman
This research describes the design and evaluation of screening smoke compositions based on red phosphorus (RP), in open field conditions. In defense applications, smoke is used for both signaling and screening. Defense forces use smoke screening over their operational areas to conceal positions and activities from the ground or air observation performed by the enemy. In this research, various optimized smoke charges based on RP were prepared and tested to investigate IR and VIS screening effectiveness in static and dynamic conditions and to establish the parameters that influence the screening time (ST- the active time of the small solid hot particles suspended in the air). In addition, this study projected a mathematical model to describe the concealing time of a civil or military target by optimizing the smoke compositions. The mathematical approach clarifies the limitations of reducing smoke charge while maintaining adequate screening time. The empirical mathematical model estimates the screening time of the generated solid smoke particles (aerosol) through laboratory experiments and open field studies. According to the experimental results, more hot particles should be kept in the atmosphere to maintain the smoke screen and sustain the aerosol density in the considered volume.

1 June 2015 in International conference KNOWLEDGE-BASED ORGANIZATION
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Journal Article
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BPBogdan Gheorghe Pulpea
Bogdan Gheorghe Pulpea
During the last decades, the military combat vehicles and trucks were equipped with various weapon systems and laser rangefinders, optical devices and sighting equipment. The military vehicles were thus upgraded, so they become a more attractive target for enemy fire. Since ballistic armour cannot and will never completely protect vehicles against kinetic or explosive ammunitions, various pyrotechnic countermeasure systems such as smoke screening, were designed and implemented. Generating smoke screens or flares in the desired area (around the combat armoured vehicles) is a concern of many manufacturers of pyrotechnic protection systems, aiming to protect against detection in the visual (VIS) and infrared (IR) spectrum. The goal of this article is to present a brief state-of-the-art regarding the development of pyrotechnic smoke camouflage systems and flares used to ensure countermeasures in the visible and infrared electromagnetic spectrum. Types of pyrotechnic systems and structures for the protection of military vehicles will be described briefly.

8 September 2022 in Chemistry Proceedings
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Conference Paper
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APAlice Podaru
Alice Podaru
GTGabriela Toader
Gabriela Toader
PDPulpea Daniela
Pulpea Daniela
TRTraian Rotariu
Traian Rotariu
Aurel DiaconAurel Diacon
Aurel Diacon
Lucia LeonatLucia Leonat
Lucia Leonat
Surface decontamination is a vast domain. The majority of the methods use a considerable quantity of water, requiring further treatments. This study presents an ecological method for surface decontamination, based on polymeric nanocomposites, specially designed for the removal of heavy metals and radionuclides. Besides being effective in decontaminating the surfaces, these polymeric coatings also reduce the volume of the waste materials. The novelty of this work consists of the innovative path of combining the advantages brought by the film-forming ability of polyvinyl alcohol, with the remarkable metal retention capacity of bentonite nanoclay, together with the chelating ability of alginate, and with one of two ‘new-generation ‘green’ complexing agents’: iminodisuccinic acid (IDS) and 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTC). These are used to obtain powerful, customizable, and environmentally friendly, film-forming, water-based solutions, for the surface decontamination of heavy metals or radioactive metals. Decontamination tests revealed a high decontamination efficiency for heavy metals (DF ≈ 95–98%, tested on glass surface) and also for radioactive metals (DF ≈ 91–97% for 241Am, 90Sr-Y and 137Cs, tested on metal, painted metal, plastic, and glass surfaces).This eco-friendly, low-waste, biodegradable method can successfully be employed, alternatively, to classical methods, having comparable capabilities for surface decontamination, but multiple advantages.