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Cement-based construction materials, such as mortars and concretes, are frequently exposed to aggressive environments containing chloride and sulfate ions, leading to corrosion processes that significantly affect their durability and structural performance. In many cases, these degradation phenomena are intensified in industrial environments or coastal areas, where the concentration of aggressive agents is higher. In recent years, the use of nanoparticles as functional additives in cementitious materials has gaine...

The effect of gamma irradiation on the optical band gap of polyimide film and its composites with a filler of finely dispersed powder of high-temperature superconductor (HTSC) YBa2Cu3O6.7 with concentrations of 0.05% by weight; 0.1% by weight; 0.5% by weight was studied. Optical properties were studied in the spectral range of 190-1100 nm using a Shimadzu UV-3600 spectrophotometer. Based on optical absorption spectra and optical band gap calculations for the composite system, we find that the optical band gap (Eg)...

Fertilizers are a fundamental agricultural input, necessary to maintain high yields and exploit soils and growing substrates that are otherwise unsuitable for plant breeding. Nevertheless, their overuse and mismanagement have led to significant negative environmental impacts, such as water pollution, high greenhouse gas emissions and soil degradation. Since the early 2000s, nanofertilizers have been touted as an innovation useful to improve both the sustainability and effectiveness of fertilization methods. The st...

We studied polyimide and lavsan films after exposure to varying doses of electron irradiation, mechanical loading, and temperature. It was found that at the first stage of mechanical loading, up to 1 MPa. A similar sharp increase in the relative elongation of the films by 3% was observed. This is due to the rotation of globules and the straightening of macromolecular chains in the material along the direction of the applied load. The dependence of the absorption coefficient on the wavelength per unit path length i...

The increasing amounts of agro-food waste generated globally represent a major challenge for environmental protection and sustainable development. Among these, onion peels resulting from processing, storage, and commercialization constitute an important source of bioactive compounds such as flavonoids, polyphenols, quercetin, and sulfur-containing compounds, with high potential for valorization in the field of green nanotechnologies. The study aims to valorize the extract obtained from onion peels in the green syn...

In the current nano-tech-era and smart agricultural solutions, the nanoformulations (NFs) application can elicit unpredictable responses, potentially impacting environmental components, human health, and crop performance. Accordingly, this study aimed to quantify the effects of selected nanoformulations (NF) and their conventional agrochemical counterparts on the grain-quality attributes, their technological properties, and physiological responses of crop-wheat. Specifically, selenium-species in nanoformulation (S...

Vaccinium myrtillus L. (European blueberry) hydrophilic extracts (Vm) are valuable raw ingredients for food, cosmetic and pharmaceutical applications. The high content of antioxidant compounds in blueberry can be exploited for obtaining more stable biomaterials. The goal of the study was the evaluation of the antioxidant activity (DPPH-, 2,2-diphenyl-1-pycryl-hydrazyl) of autochthonous blueberry (C-mpeni, Romania) and stabilizing of the Vm by nanoencapsulation in cyclodextrins (CD). Kinetic parameters were also ev...

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...

We present herein a thoroughly study concerning synthesis, structure and fluorescent properties of two classes of pyrrolodiazine derivatives: pyrrolopyridazine respectively pyrrolophthalazine cycloadducts. The synthesis is straight and efficient, consisting in a 3+2 dipolar cycloaddition reaction of diazinium ylides to dipolarophiles with triple bound. The structure of compounds was proven by elemental and spectral analysis. The fluorescence studies reveal that the pyrrolodiazine compounds are intense blue emitter...

Nanotechnology is increasingly being integrated into modern industrial applications, including the development of next-generation nanofertilizers (NFs) containing essential and non-essential elements such as zinc and silica. These NFs often intensify yield forming attributes without compromising the final crop quality. Larger knowledge about NFs application is still lacking in agronomic academic literature. It is particularly relevant for soybean cultivation, given its importance in human nutrition, feed industry ...

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...

Nickel (Ni) composite coatings fabricated via electrodeposition have garnered significant attention due to their enhanced microstructure, tribological performance, and corrosion resistance. This review provides a comprehensive analysis of recent advancements in Ni-based composite coatings, emphasizing the influence of embedded reinforcements such as ceramic particles, polymers, and metallic phases on their structural and functional properties. The microstructural characteristics, including grain size refinement, p...

In the context of sustainable development and the urgent need to reduce the environmental footprint of the construction industry, the reuse of recycled concrete waste in mortar formulations has emerged as a promising strategy. However, the incorporation of such waste materials typically leads to diminished mechanical performance, primarily due to the reduced chemical activity of the recycled aggregates. To address this drawback, nanoparticles have gained attention as functional additives capable of restoring or ev...

Nanoclay is increasingly being integrated into construction materials to enhance their mechanical properties. This advanced material improves the durability and strength of concrete, making structures more resilient to environmental stresses. Research shows that incorporating nanoclay into asphalt can improve its performance and longevity in road construction. The paper focuses on laboratory research on the effect of nanoclay adding on bitumen binder properties. The changes in penetration, softening point, and vis...

We present herein a thoroughly study regarding the synthesis, structure and biological activity of some hybrid diazine - polyphenols derivatives. The synthesis was performed under conventional thermal heating and microwave irradiation, by using a straight and efficient method: a N-alkylation reaction of diazine (pyridazine or phthalazine) with reactive halogenated derivatives. The structure of the hybrids was proven by elemental and spectral analysis. Under MW irradiation, the N-alkylation reaction of diazine have...

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...

Microbial immobilization is a promising strategy for various applications, including environmental remediation and bioprocess engineering. However, the efficacy of immobilization largely depends on the characteristics of the carriers. Biomass wastes are renewable and abundant resources that can be subjected to hydrothermal carbonization (HTC) for hydrochar production, a resulting carbonaceous material with a porous structure. This porous architecture offers extensive surface area and facilitates the colonization a...

Discovery of new chemosensors for M2+ cations represent a continuously and challenging issue for researcher because of their potential applications in nano and micro technologies. Among the other metals, zinc is the second most abundant transition metal ion in human body and plays a crucial role in many biological and environmental processes. In this work we present the design, synthesis and characterization of a Zn2+ chemosensors and its coordination complexes based on podants with benzimidazole - pyridine skelet...

Nanomechanical systems necessitate components with unparalleled precision and minimal frictional resistance to achieve optimal performance. Nanobearings represent a critical class of components that facilitate rotational or linear motion at the nanoscale. This paper presents a comprehensive classification of nanobearings, encompassing their structural attributes, materials employed, and operational mechanisms. Additionally, it provides a detailed mathematical formulation that describes the static and dynamic behav...

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...

This study presents a theoretical and experimental investigation of three distinct surface plasmon resonance (SPR) sensor configurations, evaluating their sensitivity and practical applications. The first configuration utilizes a commercially available SPR sensor, employing a coupling prism integrated with a thin gold layer in the well-established Kretschmann-Raether configuration for SPR excitation. The second configuration features an advanced design, incorporating a coupling prism combined with an optical multi...

In this paper, the magnesium alloy NZ30K alloyed with 0.1 wt. % Ag and clad with a 900 nm thick silver layer. It has been found that in the Ringer-Locke solution, the cylindrical sample underwent contact corrosion over the entire surface and crevice corrosion at the transition from the cylindrical to the flat part, which caused the coating delamination from the alloy under the mechanical action of hydrogen "bubbles" formed at the cathodic areas and corrosion products in the crevice, which have a higher specific vo...

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...

Modern electrochemical technologies for surface treatment of chromium based electrolytic coatings to create protective, antifriction materials are considered.The physicochemical fundamentals of the processes of electrolytic formation of conversion and composite electrolytic coatings are highlighted. The purpose of our researches is working out technology of nano-structured composite electrolytic coatings obtaining and revealing optimum mode for effective corrosion proof coatings electroplating. The coatings were d...

The efficiency of zinc oxide nanoparticles (ZnO-NPs) in inhibiting Phytophthora spp. growth in both durian fruits and stems is demonstrated. The size of ZnO-NPs used was in range of 25-50 nm in diameter. Diseased durian sample were collected from a durian orchard located in southern of Thailand. The pathogen of diseased durian was isolated for subsequent morphological identification. Three distinct strains of Phytophthora spp. (designated as PHY41, PHY45, PHY49) were successfully isolated and were found in colonie...

The article develops one-dimensional linear regression mathematical models that establish the relationship between the activation potentials Ecrev, repassivation Erep, and corrosion Ecor of the 06KhN28MDT alloy used in the production of plate-like heat exchangers and its chemical composition and structure components in model recycled water. It has been found that the limiting potential Elim of the alloy shifted in the positive direction with an increase in the content of Cr, Mo, Si, S, the volume of titanium sulph...

In contemporary agricultural practice, ensuring sufficient bioavailable macronutrients, particularly phosphorus, for plants in phosphorus-deficient soils remains a significant challenge. As a promising alternative, the application of phosphate-calcium-based nanofertilizers (NFs), with or without zinc, emerges as a suitable solution, offering targeted effects through foliar dispersion. However, current knowledge gaps persist regarding the development and colloidal properties of applied NFs and their impact on sunfl...

In the current paper the effectiveness of complex Fe-Mn-B SHS alloys and carbideforming additives into iron-carbon alloys and for obtaining 30MnB5, 22MnB5 steels and bainite cast iron has been established. The influence of alloying components on the structure and properties of the obtained alloys has been investigated. On the basis of the analysis of the obtained experimental data the influence of heat treatment on the microstructure and properties of the obtained alloys has been established. The conducted researc...

On the last few years, microwave and ultrasound irradiation has become a successful tool in modern medicinal and organic chemistry especially (but not only) because in many cases synthesis became ecologically friendly. As part of our ongoing efforts in the field of nitrogen heterocyclic derivatives, we present herein some core results obtained by our group in the field of N-alkylation and 3+2 cycloadditions reactions applied in the nitrogen heterocycles series, by using microwave and ultrasound irradiation. Compar...

Ticks (Ixodidae and Argasidae) pose significant health risks as vectors for infectious diseases, with their prevalence expanding across Europe and North America. Ticks employ sophisticated sensory mechanisms, notably utilizing Haller's organs, to locate and sense their hosts. These sensory structures detect various cues, including chemosensation, changes in atmospheric CO2 concentration, and radiant heat emitted by potential hosts. Once a host is detected, landing is facilitated by electrostatic attraction, accele...

There are situations in which human health is at risk from inhalation of hazardous substances and particles (viral epidemics, biological weapons, chlorine leaks, nuclear accidents, asbestos removal, quarrying). In response to these scenarios, emphasis is placed on respiratory protection and minimising exposure to these substances and particles. One of the most commonly used respiratory protective devices is respirators. However, respiratory protection for children is not addressed by any manufacturing or testing t...

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 dynamics of human society is directly related to the dependence on automation, and we can no longer produce almost anything without industrial automation. Automation is often associated with the industrial field, but automation has penetrated many areas of everyday life. Domains such as environmental protection, global trade, car, naval or rail traffic (increasingly intense), agriculture, construction and last but not least the medical field are some examples in which automation is present and in which they ha...

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...

Durian disease-causing organisms such as fungi can infect durian trees at any stage of development. Chemical fungicides are widely used because they are convenient and simple to use. However, it impacts the health of producers, consumers, and the environment. As a result, recommendations have been developed and established for researching zinc oxide nanoparticles (Zn-ONPs) that can inhibit fungal growth as an alternative for preventing and eliminating such fungi. The purpose of this study is to collect and isolate...

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...

An environmentally safe method - metal-vapor synthesis (MVS), was applied to produce iron nanoparticles (Fe NPs), which were conjugated with the drug methotrexate (MTX). The physicochemical properties and biological activity of the generated Fe NPs-MTX nanomaterials were analyzed. Transmission electron microscopy observations indicated that Fe NPs are stabilized in the form of aggregates with a size of 100 nm. The structure of these aggregates is similar to a -bunch of grapes-, which consists of metal particles ab...

The influence of the ultrasound on corrosion resistance of chromium-dioxide silicon nano-composition electrolytic coatings (nano-CEC) in solutions of the different concentrations of nano-particles of silicon dioxide at temperatures 293, 303, 313 K has been investigated. The research showed that the electroplating of chromium-dioxide silicon nano-CEC on steel St.3 enlarges its corrosion resistance tenfold. The least corrosion resistance has nano-CEC, which got under constant ultrasound influence, and the most - whi...

A mathematical model was developed, which is based on a multivariate regression dependence and establishes the relationship between the critical pitting temperature (CPT) of the 06KhN28MDT alloy (similar to AISI 904L steel) and its chemical composition and structural components in model circulating waters with pH 4...8 and chloride concentration from 350 up to 600 mg/liter, which correspond to industrial circulating water during the operation of heat exchangers. Based on the results of the analysis of the develope...

Electrodeposition of composite coatings based on cobalt alloys from citratepyrophosphate electrolytes is investigated. The features of the co-reduction of cobalt with refractory metals (Mo, W, Zr) directly from the electrolyte solution are due to the mutual influence of thermodynamic and kinetic characteristics of alloy-forming components. Modern electrochemical technologies for surface treatment of titanium alloys to create protective, antifriction, dielectric, and catalytically active materials are considered. T...

Nanomaterials are materials with new properties that interact through complex processes at the nanometric scale that include reactions in the quantum field and which still represent an unknown for many researchers. Improving the performance of cement mortar is generally achieved with the help of various additions. Nanoparticles have recently become a material very often used in the additive of various recipes of cementitious materials and not only, because at such a size their properties change surprisingly and th...

Biopolymers have gained notoriety due to their unique physical, chemical, and mechanical characteristics and performances. Due to their regenerability, compostability, biocompatibility, non-immunogenic, non-toxic, or non-allergenic properties, they have surpassed the boundaries of the food industry and have become fundamental components in biomedicine or the pharmaceutical industry. Thus, the most well-known applications are as drug delivery systems, tissue engineering, or wound dressings. In addition to all these...

A chemical sensor of refractive index variations, which possesses prescribed resolution, is designed, implemented and tested. Enhancement of coupling forces by the Bloch surface waves is achieved by incorporating a one-dimensional (1-D) photonic crystal (PC) into the classical Kretschmann arrangement of surface plasmon resonance. The numerical optimization approach was used to establish geometrical parameters of the photonic crystal with prescribed material constituents. The number of layers, their thicknesses, an...

In recent years there has been an increase in interest in biodegradable polymers. Biopolymers are upcoming competitors for the synthetic polymers with their profound attributes like eco-friendliness and biodegradability. They can be classified as natural biopolymers, chemically synthesized biopolymers, and microbial biopolymers. One of the most widely used chemically synthesized biopolymers is aliphatic polyester polylactic acid (PLA). It is a thermoplastic derived from renewable, organic sources such as corn star...

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...

Working in stone quarrying and stone processing poses certain risks that must not be underestimated. The safety of workers must be paramount, where work-related injuries can occur, so the use of appropriate personal protective equipment is important, but the less visible risks, such as inhalation of granite stone dust, which can penetrate the respiratory tract, lungs and lung chambers, causing silicosis, chronic obstructive pulmonary disease, kidney disease or lung cancer, must not be underestimated. Chemically, g...

High-Entropy Alloys (HEAs) have higher mixing entropy than the conventional alloys and intermetallic compounds and form the stabile solid solutions with disordered structure. They exhibit unique and special properties, in particular high hardness, wearresistance, significantly high strength, structural stability, good corrosion, and oxidation-resistance. HEAs -exotic-, core effects are followings: high configurational entropy; sluggish diffusion; lattice distortion and cocktail effect. At the current stage, the vo...

Two-photon pulsed terahertz (THz) emission from a GaAs/AlAs double-barrier resonant tunneling diode biased into regime of self-oscillations of current has been detected. The two THz pulses are triggered at two critical points in period of current self-oscillations due to the periodic process of charge accumulation and drain in quantum well. The internal mechanism of relaxation self-oscillations, which controls the trapping and release time of electrons tunneling through the miniband, is responsible for the time de...

The aim of the research is to develop a method for betulin integration into electrospinning solutions to electrospun qualitative nanofibers webs morphology with high surface area and increase bioavailability. The main challenge in this study is to prepare betulin - containing electrospinning solutions with suitable concentrations due to limited betulin solubility in water and low alcohol concentrations. Tree concentrations of betulin extracts were obtained. The operation sequence to obtain electrospinning solution...

Gold and iron nanoparticles were generated via environmentally safe metal-vapor synthesis method applying acetone or toluene as organic dispersion medium. Biological properties of the nanoparticles were analyzed by the agar disc diffusion method using Gram-positive and Gram-negative bacteria and via in vitro cytotoxicity assays with different human cell lines. The obtained results revealed distinct biological activity profiles of the studied specimens. Fe nanoparticles (Fe NPs) demonstrated inhibitory effects agai...