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The goal of the study was the obtaining of Castanea sativa Mill., CS (sweet chestnut) antioxidant extracts and lipid fractions from skin and pulp, followed by nanoencapsulation in cyclodextrins (CDs). The nutritional and medicinal values of fruits are mainly due to the presence of low-gluten carbohydrates, vitamins, as well as essential fatty acids (FA), including omega-3. In this study, the KG variety was subjected to the Soxhlet separation of the lipid fractions (petroleum ether) and antioxidant polyphenols (eth...

Biomass is the renewable energy resource that contributes to the energy balance by conversion into heat, by combustion in specialized facilities, conversion into electricity based on steam or gas obtained that drives turbines and electric generators or in both cases combined, through the cogeneration process. However, in order to be collected from nature, it must be optimally organized so that the effects on the environment are not harmful. Also, in the conversion processes, polluting emissions must be as low as p...

An AI camouflage design was used to create an IR camouflage textile structure, utilising Grafco screen printing inks and Chromatex HD10 pigments characterised by high brightness and colour resistance. For vector image editing, CorelDRAW software was employed. The screen-printing process was carried out following these steps: frame selection, screen selection, and image preparation. The reflection index was determined using a spectrophotometric method with a UV-VIS-NIR Perkin Elmer Lambda 950 spectrophotometer, mea...

Nanotechnology is increasingly becoming a part of everyday life. Despite this growing integration, public awareness of nanotechnology's functionality, benefits, and potential risks remains limited. This is particularly true for Generation Z, the first digitally native generation, which is expected to play a pivotal role in shaping the future of technology and its applications. Given their position as future leaders and consumers, it is important to understand how Generation Z, specifically university students, per...

Basalt fiber-reinforced metal-polymer composites represent a cutting-edge class of materials that merge the robustness of metal with the pliability of polymer. Originating from natural volcanic rocks, basalt fibers possess remarkable mechanical properties, such as high tensile strength, resistance to extreme temperatures, and chemical inertness. Integrating basalt fibers into a polymer matrix like epoxy or thermoplastic resins significantly boosts the composite's resistance to dynamic impacts and its energy absorp...

Nanotechnology plays a crucial role in the development of innovative products, yet public apprehension regarding its potential risks remains a significant barrier to its acceptance. This study investigates the knowledge, attitudes, and fears associated with nanomaterials among university students in the Czech Republic, aiming to inform policy formulation that aligns with public interests. Focusing on this demographic is essential, as university students are poised to influence future public discourse and innovatio...

The current development of nanotechnology responds to climate change, sustainability issues, the energy crisis, and the need to improve the quality of life. The question, however, is what are the societal impacts and public acceptance of nanotechnology? To explore this, a pilot cross-sectional study was conducted in the Czech Republic. The main objective of this study is to discuss consumers' willingness to pay for products containing nanotechnology. A sub-objective is to present the results of a pilot cross-secti...

Environmental concerns related to the implementation of circular economy has led to the development of new generations of materials. Interest in polymer composites reinforced with natural-organic/inorganic fillers is growing. Producers of polymer composites convert their production to optimize and replace traditional products with new ones with a high content of bio, recyclable materials, for sustainability and responsible actions. Research and industrial awareness are focused on ecological composites based on nat...

Potential use of four types of fly ash waste as raw material for synthesis of photo- catalysts to be applied for wastewater treatment was investigated. In this respect the four selected fly ash types were subject to morphological characterization by dimensional analysis of particles and scanning electronic microscopy on to composition characterization by thermogravimetric analyses and X-ray fluorescence. Their potential to be used for advanced degradation of organic compounds via heterogeneous photocatalysis was i...

The mechanism for the selective adsorption of zirconium ions in a highly acidic medium by sodium-modified titanium dioxide was proposed. The mechanism of adsorption of zirconium ions in an acidic medium by this adsorbent is similar to the mechanism of adsorption of strontium ions in a neutral medium. The selectivity of Na-TiO2 is due to the positively charged surface of the adsorbent in the highly acidic medium.

In this paper were obtained waste/polymeric nanocomposites - polyamide waste (PAW) and polystyrene (PS), compatibilized with maleic anhydride grafted polystyrene, and reinforced with carbon nanofibers (CF). PolyamideWaste / polystyrene (PAW / PS) composites are studied because both components are relatively cheap, with beneficial properties, and can be processed by injection. Compatibility of polymer and waste compounds can be achieved by adding a grafted copolymer, the segments of which have physical or chemical ...

Purification of aqueous solutions from radionuclide contamination is an extremely problematic topic, which is the subject of many scientific papers. This scientific topic is very relevant to Ukraine. In particular, the synthetic adsorbents - activated carbon, zeolites, metal oxide-adsorbents TiO2, titanium or zirconium phosphates, ion exchange resins, etc., are often used for the removal of heavy metal cations Pb (II), Cd (II), Ba (II), Hg (II), Sr (II) as well as some anions Cl-, F- from the aquatic environment. ...

Currently, the task of modifying the technological properties of mineral raw materials for the construction industry, road construction and the oil industry based on clay in order to obtain the specified characteristics, provided that the production cost is reduced, is relevant. The results of the study of the acid-base characteristics of the clay suspension surface without and in the presence of modifying additives that improve the plasticity of the mass, reduce shrinkage and crack formation in baked ceramics are...

Nanoparticles, due to small size and capacity to remain in suspension, are very efficient to remediate aquifers contaminated. However, due to their small size, while nanoparticles are traveling through porous media, they can rapidly aggregate, causing their settling and deposition. These phenomena produce issues for in situ remediation, such as the loss in chemical reactivity and the unknowing about the nanoparticles distribution when they are injected in situ. Laboratory experiment has been carried out with groun...

Various eco-friendly and cost-effective hydrocarbons clean-up methods based on natural sorbents were developed and tested, in order to prevent the massive environmental damage due to the petroleum spills. Among these sorbents, natural zeolitic tuffs are easily available and have numerous adsorptive properties that make them appropriate for the removal of petroleum substances. This study aims to preliminary investigate the sorption capacity of natural zeolites from a deposit located at Racos, Brasov County, Romania...

The research of 2D carbon-based nanomaterials has become very intensive since the discovery of graphene. Many different preparation procedures of graphene and graphene derivatives have been reported. The aim of this paper was to prepare and characterize partially oxidized graphite oxides, which were prepared from nanographite by adding different amounts of potassium permanganate as an oxidizing agent. The C/O ratio was evaluated from X-ray photoelectron spectroscopy, energy dispersive spectroscopy, and elemental a...

The purpose of the paper is to obtain a new composite material based on chemically functionalized nanoparticles dispersed in plastomer matrix. The dispersion of the ZnO nanoparticles in a plastomer matrix (PETr) leads to a high-performance polymeric material with multi-functional, antibacterial, and plastomer-specific processing properties. In this paper, elastomeric nanocompound materials were selected, due to performance properties such as: antimicrobial, resistance to aggressive chemical agents, mechanical prop...

Noble metallic nanoparticles, silver (Ag) and gold (Au) especially, are very important in modern nanotechnology due to their various applications in medicine, pharmacy and diagnosis especially due to their proven antimicrobial and antioxidant activity. Both silver (AgNPs) and gold (AuNPs) nanoparticles can be synthesized using conventional or unconventional methods and, in recent years, the unconventional methods that rely on the biosynthesis of metallic nanoparticles from different plants and plant parts are cons...

Using the open-source library for calculations in the field of kinetics and thermodynamics Cantera, a software module has been developed. Computer simulation of dry reforming of methane in a membrane reactor-contactor has been performed. The one-dimensional mathematical model of gas flow in a porous catalytic coating is used. The influence of a number of parameters, such as characteristics of pores of catalytic membrane coating, and the temperature and the flow rate of the gas mixture on the dry reforming of metha...

Silver and gold nanoparticles have unique antimicrobial and antifungal properties that make them excellent candidates for applications in nanomedicine, tissue engineering and bio-imaging. Green synthesis of metallic nanoparticles is preferred over conventional chemical routes because is eco-friendly, requires no reducing agents and no toxic chemicals result. In the present research study, one-pot green synthesis of noble metallic nanoparticles, namely silver (AgNPs) and gold (AuNPs) nanoparticles, from aqueous ext...

SF6 insulating installations are today the most performing technical solution applied to high voltage devices such as circuit-breakers and surge arresters. This gas is used due to a lot of excellent insulating properties. These properties are depending on many variables, one of them is electrodes? geometry and material. Generally, when studding the dielectric breakthrough process, ideal electrode surfaces are taken in consideration. But many experimental results, different than theoretical ones, could be a consequ...

In this paper, a pipeline implementing a multi-scale approach that can be used for modelling different steps of aerogel production is presented. Closely integrated modules for aerogel structures generation, properties prediction and adsorption, diffusion and chromatography processes modelling provide various options for systematic and comprehensive study of aerogels by performing computational experiments, which allows to reduce number of laboratory experiments. The results of pipeline validation are presented for...

In all industrial branches, the last period is under the sign of economic progress, but with the lowest energy consumption and the lowest possible release of pollutants. Technologically, therefore, the removal of polluting technologies and the introduction of new "environmentally friendly" technologies are being sought. Thus, the new industrial trend is to reduce the use of molded or forged semi finished products and the introduction of cold rolled semi finished products or other processes. This transformation can...

The necessity of fulfilling as many conditions as possible in the specification resulted in the creation of composite materials. This idea developed in the aerospace industry was later used successfully in all industrial branches. The two materials that have been used are chemically distinct, each of which retains its properties in the composite, but provides the assembly with different properties and characteristics. Thus, for the continuous phase, the matrix was used an aluminum alloy, and for the discontinuous ...

Amiodarone (AMD) is an antiarrhythmic agent used for the treatment of ventricular arrhythmias, arterial fibrillation, and severe rhythm disorders. The main therapeutic disadvantage of AMD is its low oral bioavailability and low water solubility. The aim of the study was to obtain the hydroxylpropyl-?-cyclodextrin/AMD inclusion complex and to assess its degree of drug loading using a new HPLC method. The solubilizing effect of cyclodextrin on AMD was evaluated by the phase solubility method. The concentration of AM...

In this paper, combined effects of carbon fibres treatment and compatibilizer polymers (PE-g-MA) on the structure and properties of PA/PE/PE-g-MA/ functionalized carbon fibres composites were studied. The optimum formulation was used to prepare a series of nanocomposites under different technological conditions. Also, a correlation between their physico-mechanical properties and IR spectra (ATR technique) was proposed. The carbon fibres functionalisation consisted in oxidizing the nanoparticles with oxidant mixtur...

Machinery from all industries is subject to aging processes. For economic and time reasons, damage cannot be repaired by replacing worn or damaged parts, but the product must be reconditioned. One of the most used reconditioning technologies in the industry is welding. Reconditioning technologies are credible, when samples are tested standardized. In most cases, welded structures have undergone various types of destructive tests: tension, compression, torsion and fatigue.[1] Since fatigue tests cannot be made duri...

The possibility of manufacturing compact accelerometer based on prefabricated elements has been shown. Since most of the sensitive element designs at the lowest cost possible to produce at different ranges of sensitivity, so accelerometer design will be flexible in terms of wide range measuring of linear accelerations. Paper describes an original method of calibrating an autonomous unit of accelerometers. Without the use of precision rotary tables, centrifuges, and independent of the vibration reason, it is possib...

In the automotive industry, but also in other sectors, since the 80s one of the most used methods of reconditioning is welding. In this way, various technologies have been developed for each batch taking into consideration their characteristics and use. To observe and determine the correctness and economic impact of these technologies, the samples must be checked by different types of destructive and non-destructive standard tests.The most demanding destructive testing on samples is the fatigue test with alternati...

The goal of the present study is to evaluate the use of mesoporous silicate nanoparticles MCM-41 for the loading and release of the magnolol. MCM-41 has a hexagonal arrangement of mesopores, with diameters ranging from 2 to 10 nm. The homogeneity of the cylindrical pores, high surface area with uniform porosity, and good thermal stability, which make them an attractive molecular sieve for applications in sorption of large organic molecules, as well as host for quantum confinement of guest molecules. Also, the bioc...

The importance of wastewater treatment is growing rapidly with the populationпїЅs need of access to pure water and industrial process water. Different wastewater treatment technologies are available worldwide but the membrane treatment technology has earned popularity in the last decades because of cost/efficiency reasons. Polymeric membranes lead the market in membrane manufacture because they are very competitive in performance and economics. Polysulfone is one of the most used membrane material and has advantag...

Nanocomposites have been considered as a stimulating route for creating a new type of high performance material that combines the advantages of polymer and the nanoparticles. Polyamide is well known as an engineering thermoplastic material that is widely used in industrial applications for its good mechanical and thermal properties. The paper presents the study of the new nanostructured polymer composites from polyamide/oxidized graphite nanoparticles-PA/GO to manufacture, by injection, bearing seals, contact plat...

The magnetorheological (MR) fluids include ferromagnetic and paramagnetic particles suspensions with sizes included between 0.03 and 10 ?m, located in a carrier fluid (usually mineral oil). The complex fluid viscosity strong depends of magnetic field applied. Each particle can be considered a small magnet, which tends to align in the direction of the magnetic field. The magnetorheological fluids have the ability to change their viscosity when they are introduced into a magnetic field, due to the aligned particles ...

The objective of the study was to increase the solubility of amiodarone hydrochloride by complexation with hydroxypropyl-пїЅ-cyclodextrin. After complexation a cyclodextrin/amiodarone inclusion complex was formed. The use of media containing surfactants is a suitable solubilizing method and as a result, a non-ionic surfactant - Tween 80 and an anionic one - sodium lauryl sulfate have been used. The dissolution profile of amiodarone hydrochloride and that of the inclusion complex, regarding the release of the activ...

Membrane processes used in wastewater treatment are categorized as the best techniques available at this time because it has advantages in terms of quality and costs. The membranes have different properties depending on the obtaining parameters. Their properties can be influenced throughout the membrane fabrication steps: when the polymer solution is prepared, when the polymer solution is applied in form of a thin film and also even after the thin film membrane is removed from the coagulation bath. Some important ...

Metal Oxide Varistors are today used for manufacturing state of the art overvoltage protection equipment, at any voltage level, being one of the most common power electronic devices existing on the market. They are widely used because they have a very high non-linear dependence between the applied voltage and the resulting current, and a relatively high energy absorption capability in case of normal overvoltage shocks or even in case of permanent overvoltages. Researches could be carried out both for finding a new...

Cyclophosphamide - N,N - bis (2 - chloroethyl) - 1,3,2 пїЅ oxazaphosphinan пїЅ 2 -amine 2-oxide is one of the widely used drugs in cancer treatment, which presents genotoxic, carcinogenic, mutagenic and teratogenic potential. Previously reported studies proved that long time exposure to cyclophosphamide and their metabolites leads to negative effects upon the environment and human health. Therefore, there is a need for more performant treatment processes for cyclophosphamide advanced degradation from which heterog...

The results of experimental research of hydration process of highly dispersed systems based on saponit-containing waste, extracted as the solid phase of the recycled water suspension kimberlite ore enrichment process of the diamond industry. Saponitcontaining sludge was dehydrated and subjected to mechanical activation on the planetary ball mill. Mechanical activation of raw material more than 60 minutes does not increase the specific surface area of samples was found. Specific surface area is achieves the maximum...

Tungsten carbides coatings are one of the mo st promising coatings used against wear and corrosion in industry, in particular in aerospace, automation, transportation and power generation system. The paper presents the investigation of WC-Co coatings produced by high velocity oxy- fuel (HVOF) spraying method using two feedstock powders with different particles granulation. The substrate selected for depositions was a C45 steel. The morphology and phases modification of the coatings was analyzed by Scanning Electro...

Titanium is a biocompatible material used in dentistry as una lloyed (minimum purity 99.4%) and alloyed, the most widely used is TiAl6V4 despite some reservations about the releasing of Al and V ions, which can be accumulated in the tissues. To increase the surface contact between the implant and bone, facilitating osseointegration the implants are coated with titanium or ceramic mate rials leading to a ro ughness surface which creates conditions for bone growth, resulting a better anchoring between the implant an...