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The fall of 2023 was atypical both in terms of recorded temperatures and accumulated precipitation. September and October retained many characteristics of an authentic summer, with this year experiencing up to 22 summer days, 16 tropical days, and 3 heatwave days. The weather conditions this autumn were influenced by the atypical position and evolution of baric centers, as well as the warm advection at the 500hPa level

The recovery of palladium from aqueous solutions is important due to its critical role in various industrial applications and the growing demand for sustainable resource management. This study investigates the potential of hybrid materials composed of Mg3Al layered double hydroxides (LDHs), chitosan, and ionic liquids (methyl trialchil ammonium chloride) for the efficient adsorption of palladium ions from low-concentration aqueous solutions. Comprehensive characterization techniques, including X-ray diffraction (RX), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and thermogravimetric analysis (TG), were employed to elucidate the structural and compositional properties of the hybrid materials. The results of the batch adsorption experiments demonstrate that each component contributes synergistically to the adsorption process, significantly enhancing the overall efficacy of palladium recovery. Furthermore, the method of preparing the adsorbent material was found to impact the effectiveness of palladium recovery. Among the materials tested, the chitosan/Mg3Al/IL hybrid exhibited the highest adsorption capacity (qmax = 98 mg/g), suggesting that the ionic liquid functionalization is most beneficial when applied during the hybrid material synthesis, rather than during the LDH synthesis process. This research underscores the viability of hybrid materials as a sustainable approach to palladium recovery, contributing to advancements in environmental remediation technologies.

Bacterial contamination is a major public health concern on a global scale. Treatment resistance in bacterial infections is becoming a significant problem that requires solutions. We were interested in obtaining new polymeric functionalized compounds with antibacterial properties. Three components (polymeric amine, aldehyde, and phosphite) were used in the paper in a modified “one-pot” Kabachnik–Fields reaction, in tetrahydrofuran at 60 °C, to create the N-C-P skeleton in aminophosphonate groups. Two copolymers were thus prepared starting from an acrylonitriledivinylbenzene (AN-15%DVB) copolymer containing pendant primary amine groups modified by grafting aminophosphonate groups, i.e., aminobenzylphosphonate (Bz-DVB-AN) and aminoethylphosphonate (Et-DVB-AN). The two copolymers were characterized by FT-IR spectroscopy, SEM-EDX, TGA, and antibacterial properties. It was shown that the novel products have antibacterial qualities against S. aureus and E. coli bacteria. The sample with the strongest antibacterial activity was Et-DVB-AN. We assessed how well the Weibull model and the first-order kinetic model represent the inactivation of microbial cells in our samples. The main advantage of the new antibacterial agents developed in this work is their easy recovery, which helps to avoid environmental contamination.

The present study aimed to test the solubility of SiO2 in a PbO2 host glass matrix. The new glass system with chemical composition xSiO2∙(100-x)∙PbO2 (in mol%) was obtained at low temperature using the melt-quenching technique. The method proposed for the characterization of the glass system includes X-ray diffraction (XRD), Differential Scanning Calorimetry (DSC), inductively coupled plasma mass spectrometry (ICP-Ms), Fourier Transform Infrared (FTIR), and Electron Spin Resonance (ESR) spectroscopy. Understanding the relationship between the oxide composition, structure, chemical durability, and thermal characteristics of obtained materials is essential for further developing the new glass crystalline material (GCM) compositions with specific desired properties.

Since semiconductor-based photocatalysis uses solar energy as a free and sustainable energy source and inoffensive photocatalysts, it has been found to be a promising green approach to eliminating dyes, antibiotics, and other pharmaceuticals from water that has been contaminated. In this study, a distinctive magnetic separable Fe3O4-ZnO:V photocatalyst is reported. ZnO:V semiconductors have been produced by seed-assisted growth over preformed magnetite to develop Fe3O4-ZnO:V nanocomposites. The results indicated nanocomposites with the structure of Fe3O4, ZnO:V, according to the findings of the XRD, XPS, and HRTEM investigations. Additionally, magnetic studies revealed at room temperature, the nanocomposite exhibited superparamagnetic properties. Electrochemical Impedance Spectroscopy (EIS) was employed to characterize the ability of the Fe3O4-ZnO:V nanocomposites to transfer electrons. Furthermore, the impact of dopant on optical characteristics was evaluated. When exposed to rhodamine B (RhB), all the samples exhibited photocatalytic activity. Through the use of an ESR experiment and the spin-trapping technique, the existence of reactive oxygen species (ROS) at the solid–liquid interface was demonstrated, and their impact on the samples’ photocatalytic activity was highlighted. After recycling, XRD, XPS, and SEM were performed to illustrate the stability of the material. The impact of V doping on the morphologic, structural, and compositional properties of magnetically separable Fe3O4-ZnO:V composite nanoparticles for photocatalytic applications is the innovative aspect of our work.

Our study is focused on the structural and morphological characteristics, optical behaviour and photocatalytic properties of undoped and 5 at% Eu3+-, Gd3+- and Y3+-doped CeO2 nanoparticles prepared by a green hybrid sol-gel combustion method. Several techniques such as X-ray diffraction powder (XRD), Transmission Electron Microscopy (TEM), UV-Vis spectroscopy, Photoluminescence spectroscopy (PL) and Electron Paramagnetic Resonance (EPR) have been used to investigate the obtained samples. Moreover, the correlation between the characteristics and properties has been studied. The nanoparticles observed by TEM exhibit a pseudo-spherical shape, except for Y3+-doped CeO2, which presents an acicular shape. The average size of undoped and rare-earth-doped CeO2 nanoparticles is below 10 nm, in good agreement with the calculations performed based on XRD analyses. From UV-Vis analyses it has been deduced that with doping the band gap energy decreases, which shows that additional levels are introduced by doping into the CeO2 band gap. The EPR spectra evidence similar behaviour for all doped samples. The photocatalytic activity was evaluated by the degradation of rhodamine B (RhB) under UV light irradiation. The photodegradation mechanism has been studied in depth based on the formation of electron-hole pairs, and to evidence the reactive oxygen species, ESR coupled with spin-trapping experiments was performed. In the case of Y-doped CeO2 nanoparticles, the generation of both •OOH and •O2− radicals involved in RhB photodegradation was highlighted.

Glass samples from vitreous system 1.5Ag2O98.5%[0.47B2O3(0.53-x)CaOxP2O5] with 0 £ x £ 0.08 have been obtained by undercooled method. The magnetic species existing in glass powders have been highlighting by mean of electronic paramagnetic resonance (EPR). The resonance linewidth analysis reveal the interactions between magnetic ions.

On November 2020, the Law No. 239/2020 for amending and supplementing Law No. 227/2015 on the Fiscal Code introduced an incentive regarding early education. Thus, according to the law mentioned, expenses with early education are not deductible when the income tax is calculated, but taxpayers that incur this type of expenses subside them from the income tax owned, but not exceeding 1,500 RON/month for each child. If the amount exceeded the income tax owed, according to the law for the amendment of the Fiscal Code, the difference could have been subsided, in order, from the payroll tax retained by the taxpayer for the employees, from the VAT owed or from the excise duties owed. Currently, on the basis of the questions related to the way of interpretation and application of the regulations regarding the incentives provided for early education, the government decided to suspend the incentive till the end of 2021. In order to consider the fact that in the first quarter of 2021 there were taxpayers that incurred expenses with early education for which they could have benefited from incentives, the Government Ordinance No. 19/2021 regarding certain fiscal measure, as well as on amending and supplementing certain pronouncements in the fiscal field and, based on this, the Order of the President of the National Agency for Fiscal Administration No. 653/2021 for the approval of the model and of the way of filling and managing the 711 form “Statement of adjustment for the early education expenses”, which states the use of a new form only for those who applied the incentive for early education and had to deduct the amounts spent from other taxes owed as well, not only from the income tax.

In this paper, we propose a simple procedure to obtain multi-walled carbon nanotubes (MWCNTs) decorated with TiO2–Ag nanoparticles (MWCNT–TiO2–Ag). The MWCNTs were decorated with TiO2–Ag via combined functionalization with –OH and –COOH groups and a polymer-wrapping technique using poly(allylamine)hydrochloride (PAH). TiO2-modified Ag nanoparticles were synthesized via the Pechini method using a mixture of acetylacetonate-modified titanium (IV) isopropoxide with silver nitrate (with Ag+/Ti4+ atomic ratios of 0.5%, 1.0%, 1.5%, 2.0%, and 2.5%) and L(+)-ascorbic acid as reducing agents. XRD analysis revealed the formation of nanocomposites containing CNT, anatase TiO2, and Ag. The presence of nanoparticles on the MWCNT surfaces was determined using TEM. The morphology of the TiO2–Ag nanoparticles on the MWCNT surfaces was also determined using TEM. UV–Vis investigations revealed that an increase in the ratio between Ag+ and Ti4+ decreased the band gap energy of the samples. The characteristic vibrations of the TiO2, Ag, and C atoms of the graphite were identified using Raman spectroscopy. The photocatalytic activity of the MWCNT–TiO2–Ag nanocomposite was assessed by examining the degradation of Allura Red (E129) aqueous solution under UV irradiation. The dye photodegradation process followed a pseudo-first-order kinetic with respect to the Langmuir–Hinshelwood reaction mechanism. The spin-trapping technique evidenced that •O2− was the main species generated responsible for the Allura Red degradation.

The rapid development of technological processes in various industrial fields has led to surface water pollution with different organic pollutants, such as dyes, pesticides, and antibiotics. In this context, it is necessary to find modern, environmentally friendly solutions to avoid the hazardous effects on the aquatic environment. The aim of this paper is to improve the photocatalytic performance of zinc oxide (ZnO) nanoparticles by using the plasmonic resonance induced by covering them with gold (Au) nanoparticles. Therefore, we evaluate the charge carriers’ behavior in terms of optical properties and reactive oxygen species (ROS) generation. The ZnO-Au nanocomposites were synthesized through a simple chemical protocol in multiple steps. ZnO nanoparticles (NPs) approximately 20 nm in diameter were prepared by chemical precipitation. ZnO-Au nanocomposites were obtained by decorating the ZnO NPs with Au at different molar ratios through a reduction process. X-ray diffraction (XRD) analysis and transmission electron microscopy (TEM) confirmed the simultaneous presence of hexagonal ZnO and cubic Au phases. The optical investigations evidenced the existence of a band-gap absorption peak of ZnO at 372 nm, as well as a surface plasmonic band of Au nanoparticles at 573 nm. The photocatalytic tests indicated increased photocatalytic degradation of the Rhodamine B (RhB) and oxytetracycline (OTC) pollutants under visible light irradiation in the presence of ZnO-Au nanocomposites (60–85%) compared to ZnO NPs (43%). This behavior can be assigned to the plasmonic resonance and the synergetic effects of the individual constituents in the composite nanostructures. The spin-trapping experiments showed the production of ROS while the nanostructures were in contact with the pollutants. This study introduces new strategies to adjust the efficiency of photocatalytic devices by the combination of two types of nanostructures with synergistic functionalities into one single entity. ZnO-Au nanocomposites can be used as stable photocatalysts with excellent reusability and possible industrial applications.

Environmental pollution from organic contaminants caused by textile dyeing is a real danger. Wastewater from the textile industry has high organic loads, as well as dyes and chemical compounds used in their preparation. Among the azo dyes, Congo red (CR) dye is widely used as a model in the experimental studies of textile wastewater treatment. Heterogeneous photocatalysis consists of UV or VIS light irradiation of various types of organic compounds in water in the presence of a solid catalyst; it is considered an important technique for the purification and reuse of aqueous effluents. In the present study, two novel compounds of β-phosphonate-type glycine pendant groups grafted on S-DVB copolymer were used for the decontamination of Congo red dye polluted water. They were characterized by FTIR spectroscopy, scanning electron microscopy, EDX spectroscopy, thermogravimetric analysis and UV-VIS spectroscopy. By using 25 mg/L initial concentration of Congo red dye and a catalyst concentration of 1 g/L and 240 min of irradiation, a photocatalysis efficiency of 98.6% in the case of [(diethyl)(phosphono)methylene]glycine pendant groups grafted on styrene-6.7% divinylbenzene copolymer (EthylAmAcid material), and of 83.1% in the case of [(dibenzyl)(phosphono)methylene]glycine pendant groups grafted on styrene-6.7% divinylbenzene copolymer (BenzylAmAcid material), respectively, was achieved.

(1) Introduction: Chemical pollutants disposed of various branches of industry pose a significant threat to both the aquatic environment and human health. A specific class of pollutants is given by hardly biodegradable organic compounds coming mainly from pharmaceuticals, personal care products and industrial dyes. These pollutants are identified in water bodies (surface or underground) used as a source of water in drinking water treatment plants, the classic technologies for their elimination being inefficient. Exploring new processes and transposing them on an industrial scale in order to develop innovative, operationally and energy-efficient technologies is a complex approach, supported by both theoretical and experimental investigations, numerical modeling and virtual experiment, being basic steps in shortening the time required and increasing accuracy for developing new methods. (2) Materials and methods: Based on laboratory-level and functional model studies, the combined advanced oxidation processes (by photolysis and photocatalysis) and separation at the interface of photocatalytic ultrafiltrating membranes impregnated with elements based on carbon nanotubes (MWCNTs) decorated with ZnO particles, in the presence of active oxygen species (dissolved ozone), were investigated. The paper presents a methodology and a numerical model for modeling hybrid processes of advanced oxidation and membrane separation in photolysis reactors, as a preliminary step in the development of a water decontamination technology on an industrial scale. The model deals with a coaxial reactor configuration, being based on concepts from fluid mechanics (CFD—Computational Fluid Dynamics) assembled in a multi-physical model that incorporates elements of fluid flow, radiation distribution in the reactor and the dynamics of dissolved ozone photolysis processes, both in the reactor volume and at the filter membrane interface. (3) Results: The results obtained from virtual experiments, at different operating parameters of the reactor allowed the determination of the flow regime in the reactor by highlighting active areas, evaluating the efficiency of disinfection processes and photochemical processes (photolysis, photocatalysis) and by analyzing the reaction dynamics of dissolved ozone in the presence of UV radiation, useful in establishing the technical specifications necessary to make the model on a real scale.

Nanocomposites based on half-metallic FePt (L10) magnetic nanoparticles coated with the semiconducting conjugated polymer poly(3-hexylthiophene-2,5-diyl) (P3HT) show a significant reduction in the magnetic coercivity. This study adopts a physical approach based on chemical potential equalization at the interface. The underlying charge/spin transfer mechanism unveils an imbalance: only spin-down polarized electrons are allowed to be transferred from the semiconductor to the half-metal (spin-down) conduction band, while spin-up states remain blocked at the interface. This process determines an excess of spin-up states on the P3HT side, and due to a RKKY mechanism, this effective spin system becomes ferromagnetic polarized. Due to this proximity effect, the conjugate polymer becomes exchange coupled to the hard magnetic FePt (L10) phase, thus reducing the coercivity of the half-metal. These processes make this type of composite suitable for magnetic recording applications.

In this paper, we present the synthesis of new polymeric adsorbents derived from macroporous chloromethylated styrene–divinylbenzene (DVB) copolymers with different cross-linking degrees functionalized with the following aminobenzoic groups: styrene—6.7% DVB (PAB1), styrene—10% DVB (PAB2), and styrene—15% DVB (PAB3). The new polymeric products, PAB1, PAB2, and PAB3, were characterized by FTIR spectroscopy, thermogravimetric analysis, and EDX, SEM, and BET analysis, respectively. The evolution of the functionalization reaction was followed by FTIR spectroscopy, which revealed a decrease in the intensity of the γCH2Cl band at 1260 cm−1, and, simultaneously, the appearance of C=O carboxylic bands from 1685–1695 cm−1 and at 1748 cm−1. The thermal stability increased with the increase in the cross-linking degree. The data obtained from the EDX analysis of the novel cross-linked copolymers confirmed the functionalization with aminobenzoic groups through the presence and content of nitrogen, as follows: PAB1: N% = 0.47; PAB2: N% = 0.85; and PAB3: N% = 1.30. The adsorption performances of the novel polymeric adsorbents, PAB1, PAB2, and PAB3, were tested in the adsorption of three antibiotics, tetracycline, sulfamethoxazole, and amoxicillin, from aqueous solutions, by using extensive kinetic, equilibrium, and thermodynamic studies. The best adsorption capacity was demonstrated by the tetracycline. Amoxicillin adsorption was also attempted, but it did not show positive results.

In this data article, we present supplementary data related to the research article entitled “Starch-coated green synthesized magnetite nanoparticles for removal of textile dye Optilan Blue from aqueous media” Stan et al., 2019. Data interpretations are included in the related research article Stan et al., 2019. The synthesized starch-coated Fe3O4 nanoparticles (ST-coated Fe3O4 NPs) were analyzed by scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM) to illustrate the shape and surface coating of nanoparticles. Moreover, the Brunauer-Emmett-Teller (BET) technique was used to evidence starch deposition on magnetite nanoparticles. The obtained nanocomposites were used for adsorption of Optilan Blue (OB) in batch conditions and the optimum agitation speed and point of zero charge (pHpzc) were established. After OB adsorption on ST-coated Fe3O4 NPs, the nanocomposites were analyzed by transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). The stability of starch coated Fe3O4 NPs in the acidic as well as alkaline pH was also evidenced by FTIR spectroscopy. In addition, to test the stability of ST-coated Fe3O4 NPs, leaching experiments were carried out. The experimental data were compared with isotherm and kinetic models in order to determine the most suitable for fitting.

A closed-cycle technology regarding the use of an exhausted Pd-based adsorbent as a photocatalyst in the degradation process of phenol is presented. Pd (II) represents a precious metal of great economic importance. Its obtained from natural sources become more difficult to achieve. Therefore, also considering the regulations of the “circular economy,” its recovery from secondary sources turn out to be a stringent issue in the last years. Pd(II) ions are removed from aqueous solution through adsorption onto Florisil (an inorganic solid support—magnesium silicate) impregnated with Cyphos IL 101 (trihexyl tetradecyl phosphonium chloride). It was observed that the presence of the ionic liquid (IL) in the adsorbent structure doubles the adsorption efficiency of the studied materials. The newly obtained Pd-based photocatalyst was exhaustively characterized and was used in the degradation process of phenol from aqueous solutions. The phenol degradation process was studied in terms of the nature of the photocatalyst used, time of photodegradation and solid: liquid ratio. It was observed that both the presence of IL and Pd lead to an increase in the efficiency of the phenol degradation process. The new Pd-based photocatalyst could be efficiently used in more cycles of phenol photodegradation processes. When is used as a photocatalyst the Florisil impregnated with IL and loaded with 2 mg/g of Pd, a degree of mineralization of 93.75% is obtained after 180 min of irradiation of a phenol solution having a concentration of 20 mg/L and using a solid:liquid ratio = 1:1.

N-doped graphene-ZnO hybrid materials with different N-doped graphene:ZnO wt% ratios (1:10; 1:20; 1:30) were prepared by a simple and inexpensive sol-gel method. The materials denoted NGr-ZnO-1 (1:10), NGr-ZnO-2 (1:20), and NGr-ZnO-3 (1:30) were investigated with advanced techniques and their morpho-structural, photocatalytic, and electrocatalytic properties were reported. Hence, pure N-doped graphene sample contains flakes with the size ranging from hundreds of nanometers to micrometers. In the case of all NGr-ZnO hybrid materials, the flakes appear heavily decorated with ZnO nanoparticles, having a cauliflower-like morphology. The X-ray powder diffraction (XRD) investigation of N-doped graphene sample revealed that it was formed by a mixture of graphene oxide, few-and multi-layer graphene. After the ZnO nanoparticles were attached to graphene, major diffraction peaks corresponding to crystalline planes of ZnO were seen. The qualitative and quantitative compositions of the samples were further evidenced by X-ray photoelectron spectroscopy (XPS). In addition, UV photoelectron spectroscopy (UPS) spectra allowed the determination of the ionization energy and valence band maxima. The energy band alignment of the hybrid materials was established by combining UV–Vis with UPS results. A high photocatalytic activity of NGr-ZnO samples against rhodamine B solution was observed. The associated reactive oxygen species (ROS) generation was monitored by electron paramagnetic resonance (EPR)-spin trapping technique. In accordance with bands alignment and identification of radical species, the photocatalytic mechanism was elucidated.

This paper is directed towards the development of safe, and thermally stable solid polymer electrolytes. Linear phosphorus-containing (co)polyesters are described, including their synthesis, thermal analysis, conductivity, and non-flammability. Polycondensation of phenylphosphonic dichloride (PPD) with poly(ethylene glycol) (PEG 12000) with and without bisphenol A (BA) was carried out using solid-liquid phase transfer catalysis. Potassium phosphate is used as base. Yields in the range of 85.0–88.0%, and inherent viscosities in the range of 0.32–0.58 dL/g were obtained. The polymers were characterized by gel permeation chromatography, FT-IR, 1H- and 31P-NMR spectroscopy and thermal analysis. Their flammability was investigated by measuring limiting oxygen index values. The polymers are flame retardants and begin to lose weight in the 190 °C–231 °C range. Solid phosphorus- containing (co)polyesters were complexed with lithium triflate and the resulting ionic conductivity was determined. Conductivities in the range of 10−7–10−8 S cm−1 were obtained.

The aims of this study were the synthesis, characterization and the testing of vinyldiphenylphosphonium salt phytotoxicity. Phytotoxicity of the synthesised salt was tested on Cucumis sativus L. seed germination and early seedling growth, at five different concentrations, using a standardized toxicity test. Endpoints included the determination of some seedling parameters: root and shoot length, root and shoot biomass, root and shoot dry weight ratio and final germination percentage. The vinyldiphenylphosphonium salt showed moderate to strong root length and root biomass inhibition, which increases progressively with the increasd of the concentration level.

Polyphosphonates of high molecular weights were prepared from chloromethylphosphonic dichloride (CMPD) and 4,4’-sulfonyldiphenol (SDP) by two-phase interfacial polycondensation (l–l), in an organic solvent-aqueous alkaline solution system, with a phase-transfer catalyst, at –8 º – 0 ºC. Alternative method, namely vapor-liquid interfacial polycondensation (v–l) of the same reagents gave better results (higher inherent viscosities and molecular weights). The polymers were characterized by spectroscopic techniques IR and 1H-NMR. The molecular weights and thermal stability determinations were carried out by gel chromatography and thermogravimetry. The effect of reaction temperature on yield and inherent viscosity in l–l and v–l interfacial polycondensation was studied. In l–l system the highest inherent viscosities were obtained at –8 º – 0 ºC, whereas in v–l system the maximum inherent viscosity was obtained at 120 ºC.

The functionalization of a crosslinked chloromethylated polystyrene 8% divinylbenzene copolymer with phosphonic ester groups is detailed. The reacton conditions were studied in order to determine the optimal conditions for obtaining only diesters. A statistical method for the calculation of the fraction of repetive units for the inited and final resin is proposed.

The adsorption performance of Amberlite XAD-8 impregnated with di(2-ethylhexyl) phosphoric acid (DEHPA) in the process of Cr(III) ion removal from aqueous solutions was examined. The equilibrium adsorption data were well described by the Langmuir model. The values of the dimensional separation factor, R L , indicated favourable adsorption. The maximum adsorption capacity of the DEHPA-impregnated XAD-8 material was 5.64 mg Cr(III) ion/g. The kinetics of the adsorption process were best described by the pseudo-second-order kinetic equation. The variation in the extent of adsorption with temperature was used to evaluate the thermodynamic parameters for the process. The values of ΔH 0 and ΔG 0 obtained showed that the adsorption process was endothermic and spontaneous. The adsorption activation energy also showed that the process was endothermic.