43 results match your criteria: "National Institute for Research and Development in Electrical Engineering ICPE-CA[Affiliation]"

The use of hydrogen as fuel presents many safety challenges due to its flammability and explosive nature, combined with its lack of color, taste, and odor. The purpose of this paper is to present an electrochemical sensor that can achieve rapid and accurate detection of hydrogen leakage. This paper presents both the component elements of the sensor, like sensing material, sensing element, and signal conditioning, as well as the electronic protection and signaling module of the critical concentrations of H.

View Article and Find Full Text PDF

This study investigates the synthesis and characterization of acrylic resin/kaolin composites for dielectric applications. Acrylic resin, while widely used for its mechanical strength and ease of processing, exhibits limited dielectric properties, which restrict its use in high-performance electrical insulation. To address this, varying concentrations (0-70%) of raw kaolin, containing 71% kaolinite, were incorporated into an acrylic resin matrix to enhance its dielectric strength and thermal stability.

View Article and Find Full Text PDF

Influence of Hydration and Temperature on the NaCO Based Transducer Voltage.

Micromachines (Basel)

October 2024

3Nano-SAE Research Center, Faculty of Physics, University of Bucharest, P.O. Box MG 38, 077125 Bucharest-Magurele, Romania.

Article Synopsis
  • The study investigates enhancing voltage output from NaCoO by doping it with sodium (up to x = 0.88) and optimizing the p-type thermoelectric leg's efficiency.
  • Two unique sample geometries were tested under varying conditions, including the application of a magnetic field, while analyzing the impact of hydration on sodium cobaltite properties at temperatures between 300 and 380 K.
  • The research discovered that water injection significantly increased current and power, reaching 75-100 µW at 350-360 K, and led to the development of an electronic circuit for voltage enhancement and energy storage, proposing a potential application in humidity and temperature sensing.
View Article and Find Full Text PDF

Heavy metals can accumulate and migrate in soil environments and can negatively affect crops and consumers. Because an increased incidence of chronic diseases can be observed, food security has become a high-priority concern. In the present work, we evaluate the impact of heavy metals on bioactive compounds and elemental content from onions.

View Article and Find Full Text PDF
Article Synopsis
  • Persistent organic pollutants (POPs) are harmful chemicals that can hurt the environment and living things.
  • This review looks at how tiny organisms like bacteria and fungi can help break down these pollutants in water, which is a better option than traditional cleanup methods.
  • It emphasizes the need for improving these biological techniques and finding better ways to use these organisms to protect our environment.
View Article and Find Full Text PDF

The behavior of two polymeric protective paint coatings (epoxy and polyurethane) applied over an epoxy primer coating on steel plates was investigated in this study, focusing on their role in providing anticorrosive protection against various climatic stress factors. Among the numerous climatic factors that can affect the lifetime of anticorrosive coatings, the following were selected for this work: dry heat, UV radiation, humidity, and extreme conditions such as salt fog, marine atmosphere, and alpine atmosphere. The objective was to determine the remaining lifetime of these protective coatings before replacement is needed to prevent damage to the equipment they protect.

View Article and Find Full Text PDF

This research investigates novel polymeric composite materials for automotive interior trim applications. The composites utilize recycled polypropylene (PPr) matrix and carboxymethylcellulose (CMC) as filler (PPr/CMC: 100/0, 95/5, and 90/10 wt.%).

View Article and Find Full Text PDF
Article Synopsis
  • * The developed foam (PUF/AgNPs) shows strong antimicrobial properties against various bacteria and fungi while remaining non-toxic to human skin cells, making it safe for biomedical use.
  • * With impressive durability, enhanced material strength, and potential applications in healthcare settings (like mattresses), this innovation aims to improve patient safety and reduce hospital-acquired infections.
View Article and Find Full Text PDF

This paper presents the obtaining and characterization of recycled polypropylene/strontium ferrite (PP/SrFeO) polymer composite materials with applications in the electromagnetic shielding of vehicle interiors (mainly automotive electronics-carcasses) from the electromagnetic radiation emitted mainly by exterior sources-electrical lines and supply sources-in terms of the development of the new electrical vehicles. With this aim, suitable polymer composite materials were developed using SrFeO filler in two forms (powder and concentrate). The recycled PP polymer and composite materials with a PP/SrFeO weight ratio of 75/25 and 70/30 were obtained in two stages, i.

View Article and Find Full Text PDF

Electrical properties and electro-thermal behavior were studied in composites with carbon black (CB) or hybrid filler (CB and graphite) and a matrix of linear low-density polyethylene (LLDPE). LLDPE, a (co)polymer with low crystallinity but with high structural regularity, was less studied for (PTC) applications, but it would be of interest due to its higher flexibility as compared to HDPE. Structural characterization by scanning electron microscopy (SEM) confirmed a segregated structure resulted from preparation by solid state powder mixing followed by hot molding.

View Article and Find Full Text PDF
Article Synopsis
  • The study uses thermodynamic and kinetic simulations to explore the mechanical properties and behaviors of the Ni-Ti-Cu alloy system, particularly during processes like mechanical alloying and spark plasma sintering.
  • The research includes calculations for stable and unstable phases of NiTiCu materials, demonstrating a link between these phases and microstructure changes during production.
  • Thermal properties, such as conductivity and specific heat, were measured using laser flash and differential scanning calorimetry methods, showing temperatures that align with theoretical predictions, and the findings offer insights for preparing and applying NiTiCu shape memory alloys.
View Article and Find Full Text PDF

The recovery and recycling of metals that generate toxic ions in the environment is of particular importance, especially when these are tungsten and, in particular, thorium. The radioactive element thorium has unexpectedly accessible domestic applications (filaments of light bulbs and electronic tubes, welding electrodes, and working alloys containing aluminum and magnesium), which lead to its appearance in electrical and electronic waste from municipal waste management platforms. The current paper proposes the simultaneous recovery of waste containing tungsten and thorium from welding electrodes.

View Article and Find Full Text PDF

With the technological developments witnessed in recent decades, nanotechnology and nanomaterials have found uses in several common applications and products we encounter daily. On the other hand, polyurethane (PU) foams represent an extremely versatile material, being widely recognized for their extensive application possibilities and possessing a multitude of fundamental attributes that enhance their broad usability across various application fields. By combining the versatility of PU with the antimicrobial properties of nanoparticles, this emerging field holds promise for addressing the urgent need for effective antimicrobial materials in various applications.

View Article and Find Full Text PDF

Correlation of Elemental Transfer, Bioactive Compounds and Antioxidant Activity on L. Grown in Soil with Functionalized CNT and HMs.

Metabolites

November 2023

Department of Molecular Biology and Biotechnology, Faculty of Biology and Geology, Babeș-Bolyai University, 1 Kogălniceanu St., 400084 Cluj-Napoca, Romania.

While heavy metals (HM) have been considered in recent decades to be the most common and problematic pollutants, the expansion of the list of pollutants due to the active use of carbon nanotubes (CNT) raises new questions about the benefit and harm of HM released to nature individually or fixed on CNT walls. A pot experiment was conducted to compare the effect of two classes of potential pollutants-metal salts of Pb, Mn, Cu, Zn, Cd, and Ni; and functionalized CNTs with COOH, MnO, FeO, and MnO-FeO-applied in soil, on the elemental transfer, the bioactive compounds accumulation, and the antioxidant activity in lettuce. While CNTs mainly increased the elemental transfer from soil to leaves, HM salts strongly obstructed it.

View Article and Find Full Text PDF

Rail transport comfort is ensured by predictive maintenance and continuous supervision of rail quality. Besides the specialized equipment, the authors are proposing a simple system that can be implemented on operational wagons while in service, aiming to detect irregularities in the rail and report them using the train's online communication lines. The sensor itself is an acceleration sensor connected to an electronic microcontroller able to filter the inrush acceleration and send it to the diagnosis system of the wagon.

View Article and Find Full Text PDF

The aim of this work was to evaluate the effect of six nanomaterials, namely CNT-COOH, CNT-MnO, CNT-FeO, CNT-MnO-FeO, MnO and FeO on lettuceTo determine the impact of nanomaterials on lettuce, the results obtained were compared with those for the control plant, grown in the same conditions of light, temperature, and humidity but without the addition of nanomaterial. The study found that the content of bioactive compounds and the antioxidant capacity varied in the treated plants compared to the control ones, depending on the nanomaterial. The use of CNTs functionalized with metal oxides increases the elemental concentration of lettuce leaves for the majority of the elements.

View Article and Find Full Text PDF

The European methodology for plastics, as a feature of the EU's circular economy activity plan, ought to support the decrease in plastic waste. The improvement of recycled plastics' economics and quality is one important part of this action plan. Additionally, achieving the requirement that all plastic packaging sold in the EU by 2030 be recyclable or reusable is an important objective.

View Article and Find Full Text PDF

This paper describes the preparation of new PEG-silica-MWCNTs composites as shape-stabilized phase change materials (ssPCMs) for application in latent heat storage. An innovative method was employed to obtain the new organic-inorganic hybrid materials, in which both a part of the PEG chains, used as the phase change material, and a part of the hydroxyl functionalized multiwall carbon nanotubes (MWCNTs-OH), used as thermo-conductive fillers, were covalently connected by newly formed urethane bonds to the in-situ-generated silica matrix. The study's main aim was to investigate the optimal amount of PEG that can be added to the fixed sol-gel reaction mixture so that no leakage of PEG occurs after repeated heating-cooling cycles.

View Article and Find Full Text PDF

The purpose of this work was to obtain an elastic composite material from polymer powders (polyurethane and polypropylene) with the addition of BaTiO until 35% with tailored dielectric and piezoelectric features. The filament extruded from the composite material was very elastic but had good features to be used for 3D printing applications. It was technically demonstrated that the 3D thermal deposition of composite filament with 35% BaTiO was a convenient process for achieving tailored architectures to be used as devices with functionality as piezoelectric sensors.

View Article and Find Full Text PDF
Article Synopsis
  • This paper discusses the development of five new polymer composite materials that incorporate ferrite nano-powder through mechanical mixing and hot pressing methods.
  • The ferrite powders were synthesized using a cost-effective co-precipitation technique, and the resulting composites were thoroughly characterized for their physical, thermal, and electromagnetic properties.
  • The research aims to create flexible, lightweight materials suitable for the electrical and automotive industries, showing effective protection against electromagnetic interference across various frequencies, with promising thermal stability and enhanced lifespan.
View Article and Find Full Text PDF

This article reviews the progress in developing ZnO-VO-based metal oxide varistors (MOVs) using powder metallurgy (PM) techniques. The aim is to create new, advanced ceramic materials for MOVs with comparable or superior functional properties to ZnO-BiO varistors using fewer dopants. The survey emphasizes the importance of a homogeneous microstructure and desirable varistor properties, such as high nonlinearity (α), low leakage current density (J), high energy absorption capability, reduced power loss, and stability for reliable MOVs.

View Article and Find Full Text PDF

In this paper, a modular electromagnetic transducer that achieves the optimal transfer of energy from the electric and/or magnetic fields is proposed. Both the magnetic field resonance coupling and the influence of the electric field near the copper transducers of the printed circuit board and inside the FR4-type epoxy material are considered. In our printed arrays of flat transducers, we consider face-to-face capacitances for the study of resonance coupling.

View Article and Find Full Text PDF

A Multi-Method Approach for Impact Assessment of Some Heavy Metals on L.

Molecules

January 2023

Faculty of Environmental Science and Engineering, Babeș-Bolyai University, 30 Fântânele, 400294 Cluj-Napoca, Romania.

Heavy metals represent a large category of pollutants. Heavy metals are the focus of researchers around the world, mainly due to their harmful effects on plants. In this paper, the influence of copper, cadmium, manganese, nickel, zinc and lead, present in soil in different concentrations (below the permissible limit, the maximum permissible concentration and a concentration higher than the maximum permissible limit) on lettuce ( L.

View Article and Find Full Text PDF

Chemical analysis was performed on sediment core samples collected from three salt lakes, Amara Lake, Caineni Lake, and Movila Miresii Lake, located in the northeast of the Romanian Plain. The concentration of 10 main elements, 6 heavy metals (HMs), 8 rare earth elements (REEs), and 10 trace elements (TEs)-determined using neutron activation analysis (NAA)-showed variability dependent on the depth sections, lake genesis and geochemical characteristics (oxbow, fluvial harbor/liman and loess saucer type). The assessment of pollution indices (contamination factor, pollution load index, geoaccumulation index, and enrichment factor) highlighted low and moderate degrees of contamination for most of the investigated elements.

View Article and Find Full Text PDF
Article Synopsis
  • A novel conductive composite made from a mix of HDPE and LLDPE with carbon black and graphite demonstrated comparable or superior electrical properties compared to a traditional HDPE composite with similar fillers, despite having a lower overall concentration of conductive material.
  • Testing showed that the new composite had better performance during thermal cycling, exhibiting less resistance increase and diminished negative temperature coefficient (NTC) effects, especially when radiation crosslinking was applied.
  • The physical mixing method used for creating this composite was found to be more effective in achieving lower resistivity in solid state and enhancing positive temperature coefficient (PTC) effects, suggesting that future research should focus on optimizing the preparation techniques and material properties.
View Article and Find Full Text PDF