755 results match your criteria: ""Gheorghe Asachi" Technical University[Affiliation]"

This manuscript presents an experimental investigation of the friction and wear properties of poly (methyl methacrylate) (PMMA) nanocomposites reinforced with functionalized multi-walled carbon nanotubes (MWCNTs). The aim of this study is to evaluate the potential of MWCNTs as a reinforcement material for enhancing the tribological performance of PMMA. Three types of multi-walled carbon nanotubes, i.

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A Comprehensive Review of the Current Research Status of Biodegradable Zinc Alloys and Composites for Biomedical Applications.

Materials (Basel)

July 2023

Department of Technologies and Equipments for Materials Processing, Faculty of Materials Science and Engineering, Gheorghe Asachi Technical University of Iaşi, Blvd. Mangeron, No. 51, 700050 Iasi, Romania.

Zinc (Zn)-based biodegradable materials show moderate degradation rates in comparison with other biodegradable materials (Fe and Mg). Biocompatibility and non-toxicity also make them a viable option for implant applications. Furthermore, Pure Zn has poor mechanical behavior, with a tensile strength of around 100-150 MPa and an elongation of 0.

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In the pursuit of achieving zero emissions, exploring the concept of recycling metal waste from industries and workshops (i.e., waste-free) is essential.

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Three-dimensional printing with cement-based materials is a promising manufacturing technique for civil engineering applications that already allows for the design and the construction of complex and highly customized structures using a layer-by-layer deposition approach. The extrusion mechanism is one of the most expensive parts of the 3D printer. Also, for low-scale 3D printers, based on the shape of the extruder and the geometry limitation of the mixing blade, the 3D mixture is often limited to a narrow range of materials due to the risk of layer splitting or blockage.

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Article Synopsis
  • Urban areas are expanding rapidly, increasing the demand for concrete and highlighting the need to reduce its environmental impact, especially through the use of supplementary cementitious materials (SCM) like zeolites.
  • The study replaces ordinary Portland cement (OPC) with natural zeolite at varying percentages (10%, 20%, and 30%) and investigates pore structure and microstructure changes in cement pastes over time.
  • Findings reveal that cement pastes with zeolite initially have smaller pore sizes, but by 28 days, those with 10% zeolite resemble the reference mix, while 30% zeolite increases pore size due to higher amounts of hydration products.
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  • - Haze has been a recurring issue in Southeast Asia, particularly in Malaysia, primarily caused by particulate matter (PM) that poses serious health risks.
  • - This study analyzed PM concentration data from several Malaysian cities during haze events, revealing that average PM levels often exceeded the recommended air quality guidelines, with considerable fluctuations during specific monsoon periods.
  • - The research identified that haze episodes were associated with air masses from Sumatra and noted various correlations between PM concentrations and other pollutants like CO, SO, and humidity, indicating limited domestic sources of NOx contributing to the haze.
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Does PET trays sorting affect the sustainability of plastic waste? An LCA and cost-revenue approach.

Sci Total Environ

November 2023

Department of Environmental Engineering and Management, "Gheorghe Asachi" Technical University of Iasi, 73 D. Mangeron Street, 700050 Iasi, Romania. Electronic address:

Article Synopsis
  • The management of PET tray waste is difficult because it contaminates PET bottle recycling, affecting overall recovery rates.
  • The study evaluates the environmental and economic sustainability of sorting PET trays at a Material Recovery Facility (MRF) in Molfetta, Italy, using Life Cycle Assessment (LCA) to assess different sorting scenarios.
  • Although upgraded sorting scenarios showed only minor environmental improvements (around 10% lower impacts), they resulted in slightly reduced costs (<2%) by avoiding contamination fines, making them a viable option when using optical sorting technology.
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Amylase is an enzyme used to hydrolyze starch in order to obtain different products that are mainly used in the food industry. The results reported in this article refer to the immobilization of α-amylase in gellan hydrogel particles ionically cross-linked with Mg ions. The obtained hydrogel particles were characterized physicochemically and morphologically.

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Nanocelluloses (NCs) are appealing nanomaterials that have experienced rapid development in recent years, with great potential in the biomedical field. This trend aligns with the increasing demand for sustainable materials, which will contribute both to an improvement in wellbeing and an extension of human life, and with the demand to keep up with advances in medical technology. In recent years, due to the diversity of their physical and biological properties and the possibility of tuning them according to the desired goal, these nanomaterials represent a point of maximum interest in the medical field.

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The growth and formation of primary intermetallics formed in Sn-3.5Ag soldered on copper organic solderability preservative (Cu-OSP) and electroless nickel immersion gold (ENIG) surface finish after multiple reflows were systematically investigated. Real-time synchrotron imaging was used to investigate the microstructure, focusing on the in situ growth behavior of primary intermetallics during the solid-liquid-solid interactions.

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Experimental Study on Mechanical Properties of Different Resins Used in Oral Environments.

Medicina (Kaunas)

May 2023

Department of Oral Implantology, Removable Dentures and Technology, Faculty of Dental Medicine, University of Medicine and Pharmacy "Grigore T. Popa", 700115 Iași, Romania.

: Acrylic resins remain the materials of choice for removable prosthesis due to their indisputable qualities. The continuous evolution in the field of dental materials offers practitioners today a multitude of therapeutic options. With the development of digital technologies, including both subtractive and additive methods, workflow has been considerably reduced and the precision of prosthetic devices has increased.

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Pharmacological assessment of CoO, CuO, NiO and ZnO nanoparticles via antibacterial, anti-biofilm and anti-quorum sensing activities.

Water Sci Technol

June 2023

Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, 'Gheorghe Asachi' Technical University, Bld D. Mangeron no. 73, Iasi 700050, Romania E-mail:

Infectious diseases have risen dramatically as a result of the resistance of many common antibiotics. Nanotechnology provides a new avenue of investigation for the development of antimicrobial agents that effectively combat infection. The combined effects of metal-based nanoparticles (NPs) are known to have intense antibacterial activities.

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COVID-19 Detection from Cough Recordings Using Bag-of-Words Classifiers.

Sensors (Basel)

May 2023

Faculty of Electronics, Telecommunications and Information Technology, "Gheorghe Asachi" Technical University of Iasi, Bd. Carol I 11A, 700050 Iasi, Romania.

Reliable detection of COVID-19 from cough recordings is evaluated using bag-of-words classifiers. The effect of using four distinct feature extraction procedures and four different encoding strategies is evaluated in terms of the Area Under Curve (AUC), accuracy, sensitivity, and F1-score. Additional studies include assessing the effect of both input and output fusion approaches and a comparative analysis against 2D solutions using Convolutional Neural Networks.

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Object detection is an essential component of autonomous mobile robotic systems, enabling robots to understand and interact with the environment. Object detection and recognition have made significant progress using convolutional neural networks (CNNs). Widely used in autonomous mobile robot applications, CNNs can quickly identify complicated image patterns, such as objects in a logistic environment.

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The sustainable development of innovative eco-friendly multifunctional nanocomposites, possessing superior characteristics, is a noteworthy topic. Novel semi-interpenetrated nanocomposite films based on poly(vinyl alcohol) covalently and thermally crosslinked with oxalic acid (OA), reinforced with a novel organophosphorus flame retardant (PFR-4) derived from co-polycondensation in solution reaction of equimolar amounts of co-monomers, namely, bis((6-oxido-6H-dibenz[c,e][1,2]oxaphosphorinyl)-(4-hydroxyaniline)-methylene)-1,4-phenylene, bisphenol S, and phenylphosphonic dichloride, in a molar ratio of 1:1:2, and additionally doped with silver-loaded zeolite L nanoparticles (ze-Ag), have been prepared by casting from solution technique. The morphology of the as prepared PVA-oxalic acid films and their semi-interpenetrated nanocomposites with PFR-4 and ze-Ag was investigated by scanning electron microscopy (SEM), while the homogeneous distribution of the organophosphorus compound and nanoparticles within the nanocomposite films has been introspected by means of energy dispersive X-ray spectroscopy (EDX).

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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.

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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.
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Globally, there is an increasing need for ceramic materials that have a variety of applications in the environment, for precision tools, and for the biomedical, electronics, and environmental industries. However, in order to obtain remarkable mechanical qualities, ceramics have to be manufactured at a high temperature of up to 1600 °C over a long heating period. Furthermore, the conventional approach presents issues with agglomeration, irregular grain growth, and furnace pollution.

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Untreated tannery effluent discharge, which causes severe environmental pollution. This research was performed to assess the bioremediation (multi-pollutant adsorption) potential of pre-identified and multi metal tolerant Aspergillus niger and Aspergillus tubigenesis through a stirred tank bioreactor in free and immobilized form. Physicochemical property analysis results showed that most of the tannery effluent properties were beyond the permissible limits.

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Adsorption of ibuprofen using waste coffee derived carbon architecture: Experimental, kinetic modeling, statistical and bio-inspired optimization.

Environ Res

August 2023

"Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, "Gheorghe Asachi" Technical University, Bld D. Mangeron No 73, 700050, Iasi, Romania. Electronic address:

Pharmaceuticals in water are a growing environmental concern, as they can harm aquatic life and human health. To address this issue, an adsorbent made from coffee waste that effectively removes ibuprofen (a common pharmaceutical pollutant) from wastewater was developed. The experimental adsorption phase was planned using a Design of Experiments approach with Box-Behnken strategy.

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Article Synopsis
  • Researchers produced 1.75 mm filaments for 3D printing using recycled polyethylene terephthalate glycol (R-PETG) and created specimens with varied deposition angles (10° to 40°).
  • The resulting 3D-printed specimens exhibited shape memory effects, recovering their shape when heated, even under load, and demonstrating durability over multiple heating-cooling cycles.
  • Tests showed that specimens printed at larger angles were stronger, with higher failure stresses and strains, and analyses suggested that R-PETG's glass transition temperature contributes to its effectiveness as a material for low-cost, lightweight actuators.
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The objective of the work was to obtain materials with aromatherapeutic and antibacterial properties by applying emulsions based on peppermint essential oil (PEO) onto cotton fabric. For this purpose, some emulsions based on PEO incorporated in various matrices (chitosan + gelatin + beeswax; chitosan + beeswax; gelatin + beeswax and gelatin + chitosan) were prepared. Tween 80 was used as a synthetic emulsifier.

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The paper investigates the influence of some 3D printing conditions on some physical-mechanical and technological properties of polycaprolactone (PCL) wood-based biopolymer parts manufactured by FDM. Parts with 100% infill and the geometry according to ISO 527 Type 1B were printed on a semiprofessional desktop FDM printer. A full factorial design with three independent variables at three levels was considered.

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Isotherm and Kinetic Study of Metal Ions Sorption on Mustard Waste Biomass Functionalized with Polymeric Thiocarbamate.

Polymers (Basel)

May 2023

Department of Environmental Engineering and Management, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Technical University Gheorghe Asachi of Iasi, 700050 Iaşi, Romania.

The presence of high concentrations of metal ions in effluents resulting from industrial metal coatings is a well-known fact. Most of the time, such metal ions, once they reach the environment, significantly contribute to its degradation. Therefore, it is essential that the concentration of metal ions is reduced (as much as possible) before such effluents are discharged into the environment to minimize the negative impact on the quality of the ecosystems.

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Infections in an Emergency Surgical Unit from North-East Romania.

Medicina (Kaunas)

April 2023

Department of General Surgery, "Grigore T. Popa" University of Medicine and Pharmacy, Universitatii Street, No. 16, 700115 Iasi, Romania.

: Colitis with is an important health problem that occurs with an intensity that varies between mild and severe. Surgical interventions are required only in fulminant forms. There is little evidence regarding the best surgical intervention in these cases.

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