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Silver and gold nanoparticles were produced using the pinhole discharge generated by dc non-pulsing high voltage directly in a precursor solution. Silver nitrate solution was used as the precursor for silver nanoparticles, and chloroauric acid was used as the precursor for gold nanoparticles. Effects of discharge time, precursor concentration, and additives such as reduction agent (ethylene glycol) and capping agent (polyethylene glycol and sucrose) were studied. Nanoparticles were mainly analyzed by UV-VIS spectrometry. The size of prepared nanoparticles was determined by the dynamic light scattering with backscattering detection. To determine the stability of nanoparticles, the zeta potential was measured by the electrophoretic light scattering. It was found that the absorption maximum of nanoparticles increases with the time of the discharge treatment and concentration of the precursor. The size of silver nanoparticles ranged from 10 to 1000 nm and the final solution had higher polydispersity. The size of Au nanoparticles ranged from 10 to 100 nm, depending on the precursor concentration. The most stable particles were prepared from the pure precursor solution without any additives. The addition of ethylene glycol stimulated the reduction process of nanoparticles from the solution but it decreased their zeta potential. Final particles were less stable, which started to form larger structures that tended to sediment. Added capping agent decreased the input of power needed for the stable discharge operation. The formation of silver and gold nanoparticles was confirmed by scanning electron microscopy with the energy dispersion spectrometer. Both silver and gold particles had spherical shapes. [ABSTRACT FROM AUTHOR]

In recent years, nanoparticles have emerged as an important player in a broad range of applications, especially thanks to recent advances in their synthesis. The silver and copper nanoparticles are often used due to their antibacterial and fungicidal activities, and this article presents the results of the nanoparticle synthesis using electrical glow discharge generated directly in a volume of their salt solutions. Therefore, there is no influence of air (i.e. reactive nitrogen species) as it is usual in other commonly used approaches. Nanoparticles were prepared under various experimental conditions, and they were characterized by ultraviolet/visible spectrometry, dynamic light scattering, X-ray photoelectron spectroscopy, and high-resolution scanning electron microscopy. Particles were produced without any surfactant or stabilizing agent, and some of them showed higher resistance against agglomeration during their short-term (days) storage. The nanoparticle formation mechanism was confirmed by the fast camera imaging. Thus, the developed approach can be applied for simple environmentally friendly nanoparticle production for various applications.

The paper presents an empirical study in the area of implementation theatre forum for people with mild and moderate mental retardation in an environment of sheltered housing. Forum Theatre already takes place in primary schools, in orphanages, in the Roma community and so on. There is a lack of experience and research studies with the target group of people with intellectual disabilities. The present research was carried out in several phases over a period of one year. The main objective was to determine whether it is possible to use forum theatre techniques and subjects with mild to moderate mental retardation - whether this target group will be able to process the theatre forum to engage, understand the meaning and function of these techniques and that these techniques can be used as an alternative remedy to solve the problem and conflict situations. The research sample consisted of 11 adult clients of sheltered housing with mild to moderate mental retardation and 11 members of the realization team of the forum theatre (7 Actors and 4 employees in direct care in sheltered housing). Used qualitative research methods were focus groups (always followed the realization of the theatre workshop forum), participant observation and quantitative method was a questionnaire. Research has brought new insights and information.

This paper presents results on electric discharge generation by high frequency high voltage (15–100 kHz) in NaCl solutions with different initial conductivity (100–1300 mS cm-1), and compares them with DC discharge in the same electrode configuration. A batch plasma reactor in the pin-hole configuration contained a ceramic dielectric barrier separating two planar stainless steel electrodes; barrier thickness of 0.6 mm and pin-hole diameter of 0.6 mm was used. Lissajous charts were evaluated from electric measurements for different discharge phases (electrolysis, bubble formation and discharge regular operation). Breakdown moments for different solution conductivities were determined from discharge power evaluation as a function of applied frequency. Breakdown voltage amplitude was decreased by the increasing conductivity in both regimes while frequency and current decreased. Changes of physical parameters (temperature, solution conductivity and pH) as well as production of hydrogen peroxide at different solution conductivities were compared. Solution conductivity was increased in both discharge regimes and with the initial conductivity value. Solution temperature was increased by the discharge in both regimes and with the increasing initial conductivity, too. Solution pH dropped to acidic conditions when HF or DC positive regime was applied while it was enhanced by DC negative regime.

Contamination of the environment with toxic metals such as cadmium or lead is a worldwide issue. The accumulator of metals Cannabis sativa L. has potential to be utilized in phytoremediation, which is an environmentally friendly way of soil decontamination. Novel non-thermal plasma-based technologies may be a helpful tool in this process. Plasma activated water (PAW), prepared by contact of gaseous plasma with water, contains reactive oxygen and nitrogen species, which enhance the growth of plants. In this study, C. sativa was grown in a short-term toxicity test in a medium which consisted of plasma activated water prepared by dielectric barrier discharge with liquid electrode and different concentrations of cadmium or lead. Application of PAW on heavy metal contaminated C. sativa resulted in increased growth under Pb contamination as was determined by ecotoxicology tests. Furthermore, the PAW influence on the bioaccumulation of these metals as well as the influence on the nutrient composition of plants was studied primarily by applying Laser-induced breakdown spectroscopy (LIBS). The LIBS elemental maps show that C. sativa accumulates heavy metals mainly in the roots. The results present a new proof-of-concept in which PAW could be used to improve the growth of plants in heavy metal contaminated environment, while LIBS can be implemented to study the phytoremediation efficiency., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Phosphorus (P) is an important nutrient in plant nutrition. Its absorption by plants from the soil is influenced by many factors. Therefore, a foliar application of this nutrient could be utilized for the optimal nutrition state of plants. The premise of the study is that foliar application of phosphorus will increase the yield of normal-phytate ( npa ) cultivars (CDC Bronco a Cutlass) and low-phytate ( lpa ) lines (1-2347-144, 1-150-81) grown in soils with low phosphorus supply and affect seed quality depending on the ability of the pea to produce phytate. A graded application of phosphorus (H₃PO₄) in four doses: without P (P0), 27.3 mg P (P1), 54.5 mg P (P2), and 81.8 mg P/pot (P3) realized at the development stages of the 6th true leaf led to a significant increase of chlorophyll contents, and fluorescence parameters of chlorophyll expressing the CO 2 assimilation velocity. The P fertilization increased the yield of seeds significantly, except the highest dose of phosphorus (P3) at which the yield of the npa cultivars was reduced. The line 1-2347-144 was the most sensible to the P application when the dose P3 increased the seed production by 42.1%. Only the lpa line 1-150-81 showed a decreased tendency in the phytate content at the stepped application of the P nutrition. Foliar application of phosphorus significantly increased ash material in seed, but did not tend to affect the protein and mineral content of seeds. Only the zinc content in seeds was significantly reduced by foliar application of P in npa and lpa pea genotypes. It is concluded from the present study that foliar phosphorus application could be an effective way to enhance the pea growth in P-deficient condition with a direct effect on seed yield and quality.

In this work, the potential of a microwave (MW)-induced atmospheric pressure plasma jet (APPJ) in film deposition of styrene and methyl methacrylate (MMA) precursors is investigated. Plasma properties during the deposition and resultant coating characteristics are studied. Optical emission spectroscopy (OES) results indicate a higher degree of monomer dissociation in the APPJ with increasing power and a carrier gas flow rate of up to 250 standard cubic centimeters per minute (sccm). Computational fluid dynamic (CFD) simulations demonstrate non-uniform monomer distribution near the substrate and the dependency of the deposition area on the monomer-containing gas flow rate. A non-homogeneous surface morphology and topography of the deposited coatings is also observed using atomic force microscopy (AFM) and SEM. Coating chemical analysis and wettability are studied by XPS and water contact angle (WCA), respectively. A lower monomer flow rate was found to result in a higher C-O/C-C ratio and a higher wettability of the deposited coatings., Competing Interests: The authors declare no conflict of interest.