10 results match your criteria: "National Research and Development Institute for Gas Turbines COMOTI[Affiliation]"
Biomimetics (Basel)
October 2024
Faculty of Mechanical Engineering and Mechatronics, National University of Science and Technology POLITEHNICA Bucharest, 060042 Bucharest, Romania.
A Brain-Computer Interface (BCI) processes and converts brain signals to provide commands to output devices to carry out certain tasks. The main purpose of BCIs is to replace or restore the missing or damaged functions of disabled people, including in neuromuscular disorders like Amyotrophic Lateral Sclerosis (ALS), cerebral palsy, stroke, or spinal cord injury. Hence, a BCI does not use neuromuscular output pathways; it bypasses traditional neuromuscular pathways by directly interpreting brain signals to command devices.
View Article and Find Full Text PDFMaterials (Basel)
August 2022
European Space Research and Technology Centre (ESA-ESTEC), Mechanical Department, European Space Agency, 2200 AG Noordwijk, The Netherlands.
This paper presents an experimental study on the influence of the main Laser Powder Bed Fusion (PBF-LB) process parameters on the density and surface quality of the IN 625 superalloy manufactured using the Lasertec 30 SLM machine. Parameters' influence was investigated within a workspace defined by the laser power (150-400 W), scanning speed (500-900 m/s), scanning strategy (90° and 67°), layer thickness (30-70 µm), and hatch distance (0.09-0.
View Article and Find Full Text PDFMaterials (Basel)
August 2022
Faculty of Industrial Engineering and Robotics, Politehnica University of Bucharest, 313 Splaiul Independentei St., 060042 Bucharest, Romania.
The welding process of dissimilar metals, with distinct chemical, physical, thermal, and structural properties, needs to be studied and treated with special attention. The main objectives of this research were to investigate the weldability of the dissimilar joint made between the 99.95% Cu pipe and the 304L stainless steel plate by robotic Gas Tungsten Arc Welding (GTAW), without filler metal and without preheating of materials, and to find the optimum welding regime.
View Article and Find Full Text PDFPolymers (Basel)
July 2022
National Research and Development Institute for Gas Turbines COMOTI, 220D Iuliu Maniu Avenue, 061126 Bucharest, Romania.
The paper addresses the synthesis of a nano-fibre network by coaxial electrospinning, embedding the healing agent dicyclopentadiene (DCPD) in polyacrylonitrile (PAN) fibres. Compared to other encapsulation methods, the use of nano-fibres filled with healing agent have no effect on the mechanical properties of the matrix and can address a larger healing area. Additionally, carbon nanotubes were added as nanofillers to enhance the reactivity between DCPD and the epoxydic matrix.
View Article and Find Full Text PDFInt J Environ Res Public Health
September 2021
National Research and Development Institute for Gas Turbines COMOTI, 220D Iuliu Maniu, 061126 Bucharest, Romania.
This paper presents an inside-cabin acoustic evaluation of the IAR PUMA 330 helicopter, manufactured by IAR S.A. Brasov.
View Article and Find Full Text PDFPolymers (Basel)
May 2021
Advanced Polymer Materials Group, University Politehnica of Bucharest, 011061 Bucharest, Romania.
The present paper is focused on evaluating the most suitable dispersion method in the epoxy matrix of two self-healing systems containing dicyclopentadiene (DCPD) and 5-ethylidene-2-norbornene (ENB) monomers encapsulated in a urea-formaldehyde (UF) shell, prior to integration, fabrication and impact testing of specimens. Both microstructural analysis and three-point bending tests were performed to evaluate and assess the optimum dispersion method. It was found that ultrasonication damages the microcapsules of both healing systems, thus magnetic stirring was used for the dispersion of both healing systems in the epoxy matrix.
View Article and Find Full Text PDFInt J Environ Res Public Health
May 2021
National Research and Development Institute for Gas Turbines COMOTI, 220D Iuliu Maniu, 061126 Bucharest, Romania.
The paper is presenting the experimental analysis of the use of biodiesel from waste sunflower oil and a blend of sunflower oil with palm oil as fuel for aviation turbo-engines. A comparative analysis for fuel mixtures made of Jet A + 5% Aeroshell 500 Oil (Ke) with 10%, 30%, and 50% for each bio-fuel type has been performed and Ke has been used as reference. Firstly, the following physical and chemical properties were determined: density, viscosity, flash point, freezing point, calorific power.
View Article and Find Full Text PDFMaterials (Basel)
October 2020
National Research and Development Institute for Gas Turbines COMOTI, 220D Iuliu Maniu Av., 061126 Bucharest, Romania.
The notch sensitivity of additively manufactured IN 625 superalloy produces by laser powder bed fusion (LPBF) has been investigated by tensile testing of cylindrical test pieces. Smooth and V-notched test pieces with four different radii were tested both in as-built state and after a stress relief heat treatment for 1 h at 900 °C. Regardless of the notch root radius, the investigated alloy exhibits notch strength ratios higher than unity in both as-built and in stress-relieved states, showing that the additive manufactured IN 625 alloy is not prone to brittleness induced by the presence of V-notches.
View Article and Find Full Text PDFMaterials (Basel)
October 2020
National Research and Development Institute for Gas Turbines COMOTI, 220D Iuliu Maniu Av., 061126 Bucharest, Romania.
The present study was focused on the assessment of microstructural anisotropy of IN 625 manufactured by selective laser melting (SLM) and its influence on the material's room temperature tensile properties. Microstructural anisotropy was assessed based on computational and experimental investigations. Tensile specimens were manufactured using four building orientations (along , -axis, and tilted at 45° in the plane) and three different scanning strategies (90°, 67°, and 45°).
View Article and Find Full Text PDFPolymers (Basel)
May 2020
National Research Centre for Micro and Nanomaterials, Faculty of Applied Chemistry and Materials Science, University POLITEHNICA of Bucharest, 060042 Bucharest, Romania.
The activities of this paper were focused on an in-situ fabrication process for producing two self-healing systems containing dicyclopentadiene and 5-ethylidene-2-norbornene monomers encapsulated in a urea-formaldehyde shell and integration methods applied in the epoxy matrix to analyse and compare the influences of their integration into the neat epoxy matrix. The self-healing systems were first synthesized according to a literature review, and subsequently, an optimization process was conducted for the fabrication process. Neat epoxy specimens were fabricated as reference specimens and subjected to flexural tests.
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