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This study evaluates the photoactivity of novel zeolite-based Ti O2 composites modified with metal particles for the photoreduction of Cu2+, depending on the zeolite and metal particles ( Ag or Fe) content and to establish the photoreduction mechanism. The composites have been prepared by incorporating zeolite particles in the sols during the sol-gel preparation of the Ti O2, followed by impregnation of the gels in solutions containing metal ions. The zeolite-based Ti O2 composites have been characterized using X-ray diffraction, Raman and FTIR spectroscopy techniques and TEM microscopy. The role of zeolite particles in the photoreduction process was demonstrated by using different kinetic models. The apparent constant rate for photoreduction increases in direct proportion with the content of zeolite and is higher for the composites modified with Fe than for those modified with Ag nanoparticles. The results demonstrate that composites have a higher photocatalytic efficiency than Ti O2. The experiments in this study reveal that the migration of Cu2+ in solution occurs rapidly and that the diffusion through the film on the composite's surface and, subsequently, the photoreduction process are the rate limiting steps. The role of the zeolite in photoreduction is to diminish the recombination rate of the charge carriers. [ABSTRACT FROM AUTHOR]

The paper studies the influence of work parameters expressed as brewing time, temperature of water, particle sizes and contact time on the releasing of mineral elements (Ca, Mg, Zn, Cu, Fe and Pb) in coffee infusion. The higher extractability was obtained in the first 10 minutes for infusion made of coffee samples with particles in range of 125 µm - 500 mm and hot water for Ca (33.02 mg/100g) while in case of diffusion made of coffee beans (diameter > 2 mm) in contact with cold water no lead was noticed after 60 minutes. [ABSTRACT FROM AUTHOR]

The goals of the experiments detailed below were, on one hand, to determine the nitrate and nitrite content in supermarket (greenhouse) cucumbers as compared to the cucumbers collected from farms located in two villages, Coltau and Sisesti, in Maramures County, and on the other hand to assess to what extent such content could be reduced, in order to minimise the negative impact on human health. [ABSTRACT FROM AUTHOR]

This study aims to prepare and test the capacity of a sensor based on TiO2 to detect the presence of oxygen in the damaged vacuum packages. The oxygen indicator is described, comprising nanoparticles of titania added to a sacrificial electron donor, glycerol and to a redox indicator, methylene blue (MB). The indicator is blue colored in the absence of UV light, however upon exposure to UV light its blue color becomes light blue and until it is exposed to oxygen, whereupon its original color is restored. [ABSTRACT FROM AUTHOR]

The uptake of heavy metals is a process dependent on the resistance/tolerance of plants against chemical stress. The nature of the metal and the particularities of each species influence the uptake capacity. In order to test the uptake capacity of some species, seeds of Phaseolus vulgaris and Zea mays from polluted and respectively unpolluted sites were selected for the experiment following. The authors' previous experiments on germination in the presence of metals (Fe, Cu, Zn and Pb) revealed that seeds from metalliferous fields behave differently against chemical stress compared with seeds from non-metalliferous fields. The differential behavior of the two types of seeds was observed even starting from imbibition. The aim of experiments is to investigate the accumulation abilities of non-metallophytes species such as Phaseolus vulgaris and Zea mays, analyzing the first growth stage. The analysis of the experimental data thus obtained demonstrates that harvested from polluted soil has lower uptake capacity less than the plants grown from seeds harvested from unpolluted soils. [ABSTRACT FROM AUTHOR]

The study aims to establish if the packages based on paper or LDPE modified with extract of thyme and garlic are efficient in preserving the summer salame during storage, as compared with the unmodified packages. Eight different types of packages based on paper or LDPE impregnated in the aqueous extracts of thyme and garlic were prepared and used to test their preservation activity during the storage of the summer salame, a Romanian meat product, at room temperature and light. The eight types of packages are as follows: product impregnated in extract of thyme (IP thyme) and garlic (IP garlic), summer salame packaged in unmodified paper (H) and LDPE (LDPE), summer salame packaged in paper impregnated in extract of thyme (IH thyme) and in extract of garlic (IH garlic), summer salame packaged in LDPE impregnated in extract of thyme (ILDPE thyme) and in extract of garlic (ILDPE garlic). At 0, 3 and 6 days, the following physico-chemical parameters were monitored during storage: acidity, pH, water, salt and protein content. Additionally, the changes of the organoleptic characteristics were established. It was observed that the most reduced decrease of the acidity and protein content during storage occured in the summer salame impregnated in the thyme extract and in the salame packaged in the paper impregnated in the garlic extract. Moreover, the organoleptic characteristics of the samples impregnated in the thyme and garlic extract, excepting those in packages based on LDPE were not significantly changed during storage, at room temperature and under light. [ABSTRACT FROM AUTHOR]

The chemical changes of homemade curd cheese were evaluated during storage in unmodified and modified packages with extract of garlic (Allium sativum) and thyme (Satureja hortensis), during 3 and 6 day, at room temperature. White paper and low density polyethylene have been used as packaging materials. The influence of type packaging during storage on titrated acidity, chloride, protein and dry weight content was investigated. Also, a set of measurements was performed on cheese stored at room temperature without being packed, after being treated with thyme or garlic extract by immersion for 10 minutes in the extract. The basic compounds from thyme extract and the antioxidant compounds from garlic extract influence the physico-chemical parameters of curd cheese. [ABSTRACT FROM AUTHOR]

The chemical changes of three types of cheese, yoghurt and kefir were evaluated during storage in packages containing TiO2 with two different compositions of the mixed anatase-rutile phase. The influence of TiO2 packaging during storage on titratable acidity and fat content and on the external aspect was investigated. Fourier Transformed Infrared Spectroscopy (FTIR) analyses were performed to establish whether the TiO2 penetrated the food during storage. The results showed that the TiO2 nanoparticles deposited on polyethylene surface significantly decreased acidity and fat content of the investigated cheese and yoghurt types. During storage in TiO2 nanopackages, the change in chemical parameters is accentuated as the content of rutile grows from 2.8% to 6.9%. The sensory evaluation revealed that the dairy products stored for 11 days in TiO2 nanopackages present similar colour, texture and flavour with that of the references; the samples stored in polyethylene film were found to be unacceptable. [ABSTRACT FROM AUTHOR]

The objective of this research is to determine if zeolite modified with ammonium ions has a higher capacity than natural zeolite to protect Hieracium aurantium and Rumex acetosella growing on tailing ponds, by reducing the quantity of metal ions these plants would accumulate in their roots and leaves. The influence of the amount of zeolite in the substrate (5 % and 10 % mass percentage) was also studied. The experiments were carried out in laboratory and the concentration of the ions of heavy metal in roots and leaves, after 38 days of growth was established by Flame Atomic Adsorption Spectroscopy. The pH, conductivity and redox potential for each of the substrate considered were measured. The results were statistically processed using the one-way analysis of variance (one-way ANOVA). FTIR analyses were performed to establish the structural differences between the natural and modified zeolite. Hieracium aurantium and Rumex acetosella accumulate a smaller quantity of metal ions in roots and leaves in the presence of zeolite modified with ammonium ions than in the presence of natural zeolite. Laboratory tests showed that Hieracium aurantium is more tolerant to ions of heavy metals than Rumex acetosella, as demonstrated by their translocation factors. In terms of reducing the uptake of ions of heavy metals, only the zeolite modified with ammonium has a significant protective effect on Hieracium aurantium, while both natural zeolite and zeolite modified demonstrate a significant role for Rumex acetosella, as revealed by statistical tests. [ABSTRACT FROM AUTHOR]

The experiments were performed to test the influence of amendments on the growth of Phaseolus vulgaris L. plants. The amendments tested were natural bentonite, natural zeolite modified with Ca2+ and natural zeolite modified with NH4+, respectively. The seeds of beans were planted in polluted soil mixed with 5% and respectively 10% content of amendment. Mixes with the two above-mentioned concentrations were prepared with each type of amendment considered. Soil without amendment was used as control-soil. In each of the seven experimental series, 15 seeds were planted. The height of each plant was measured and recorded after a pre-established number of days, up to one calendar month. Data were analyzed using version 16.0 (for Windows) of the SPSS software package. [ABSTRACT FROM AUTHOR]

The poplar (Populus tremula) belongs to the typical pioneer vegetation at former ore mining sites in East and Middle Europe as a result of its high metal-tolerance. Ectomycorrhizal (EM) fungi are known to contribute essentially to the tolerance of plants against abiotic stress. We have determined the absorption/accretion potential of the poplar related to heavy metals, as well as the growth rhythm of this species in conditions offered by polluted sites, correlated to the presence/absence of the microbiota in the soil attached to the root. The research unravels how the poplar (Populus tremula), as a native species can be used in remediation actions of polluted sites based on its high adaptive potential, as well as on its capacity to absorb and accumulate heavy metals. In terms of survival strategy, mycorhrised fungi attached to the polluted soil play a significant part, since they induce plants a certain resistance by diminishing the absorption of heavy metals by the host plant. We suppose that the majority of EM associations of Populus tremula, in combination with high portions of metal-chelating organic acids containing fungal partners, contributes essentially to the high tolerance of this species against high metal concentrations in the soil. [ABSTRACT FROM AUTHOR]

An active package from cardboard coated with titanium dioxide was designed for storage of fresh prepared orange juice. The organoleptical changes of the orange juice were statistically significant and revealed the preservation role of the active cardboard at 4 °C. Statistically significant positive effect on the reducing the rate of ascorbic acid degradation and on the increasing the catalase activity, respectively, was generated by coating TiO2, revealing that the semiconductor favors the preservation of the orange juice during storage. FTIR spectra revealed new compounds in the juice stored in the active package at 4 °C, but these substances has no significantly affected the characteristics of the juice. This study reveals that the TiO2‐cardboard is a promising solution to package fresh prepared orange juice and to store it in safety conditions at 4 °C for 7 days. The mechanism that ensure the preservation of juice as a result of TiO2 particles photoactivity was discussed. Practical applications: The study report about a new type of active package made from cardboard coated with TiO2 designed for storage of fresh prepared orange juice. The results showed the statistically significant and positive influence of TiO2 on preserving the organoleptical parameters, ascorbic acid content and catalase activity of the orange juice during storage for 9 days. This study reveals that the TiO2‐cardboard is a promising solution to package fresh prepared orange juice and to store it in safety conditions at 4 °C for 7 days. [ABSTRACT FROM AUTHOR]

In our experiment, we looked whether there was a chance to remediate tailing ponds with a sub-layer rich in Cu, Zn, Fe, Pb, Cr making use of native species from the regional flora, like Quercus petraea. We have determined the absorption/ accretion potential of the durmast related to heavy metals, as well as the growth rhythm of this species in conditions offered by polluted sites, correlated to the presence/absence of the microbiotis in the soil attached to the root. The research places accent on the fact that the durmast oak, as a native species can be used in remediation actions of polluted sites since it has an adaptive potential, as well as the capacity to absorb and accumulate heavy metals. In what concerns its survival strategy, mycorised fungi ,attached to the polluted soil, play a significant part, since they induce plants a certain resistance by diminishing the absorption of heavy metals by the host plant. [ABSTRACT FROM AUTHOR]

The chemical changes of three types of cheese, yoghurt and kefir were evaluated during storage in packages containing TiO2 with two different compositions of the mixed anatase-rutile phase. The influence of TiO2 packaging during storage on titratable acidity and fat content and on the external aspect was investigated. Fourier Transformed Infrared Spectroscopy (FTIR) analyses were performed to establish whether the TiO2 penetrated the food during storage. The results showed that the TiO2 nanoparticles deposited on polyethylene surface significantly decreased acidity and fat content of the investigated cheese and yoghurt types. During storage in TiO2 nanopackages, the change in chemical parameters is accentuated as the content of rutile grows from 2.8% to 6.9%. The sensory evaluation revealed that the dairy products stored for 11 days in TiO2 nanopackages present similar colour, texture and flavour with that of the references; the samples stored in polyethylene film were found to be unacceptable. [ABSTRACT FROM AUTHOR]

Tailing pond, produced from extraction and processing of heavy metals ores, not only damage native vegetation, thus leading to large areas of derelict land, but are also sources of metal contaminants in local water, air and land. Microorganisms can be important biosorbents for heavy metal remediation of contaminated soils and wastewaters. The presence of some beneficial fungi stimulated plant growth and protected the plant from metal toxicity. To establish the appropriate bioremediation method, we identified some fungi and bacteria species localized in different points and at different depths. [ABSTRACT FROM AUTHOR]

The study reports obtaining, characterization and evaluation of the preservation efficacy of nano-Ag-graphene-TiO 2 -polylactic acid (PLA) film during the storage of the curd cheese. The reusability of the active package was also evaluated. The mechanical resistance of the film was improved by 30% following the composite addition. Water vapour permeability decreased by 11-27% when the composite was incorporated into PLA in a mass percentage ranged between 0.5 and 3%. The highest fat permeability was obtained for PLA3% at 4 °C. The oxygen permeability of PLA3% is 24.6% lower than that of neat-PLA. PLA0.5% and PLA3% presented the highest antibacterial activity. PLA3% achieved the lowest solubility in food simulants at 4 °C compared to PLA and reference. The best active packages for curd storage were PLA0.5% and PLA3%. They showed also the lowest depreciation from the first to the second use. Their active role is kept 100% and 85% respectively, during the second use., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Among two-dimensional (2D) materials, such as graphene, a new family of 2D anisotropic carbides and nitrides of early transition metals (MXenes) is very interesting because of the potential applications in electronics, medicine, and photocatalysis. In this paper, preparation, morphostructural characterization, band gaps determination, and salicylic acid photodegradation ability of Ti 2 C MXene and six nanocomposites consisting of the MXene modified by TiO 2 , Ag 2 O, Ag, PdO, Pd, and Au are reported. It was confirmed using electron diffraction studies, energy dispersive X-ray spectroscopy, and high-resolution transmission microscopy that metals and metal oxides occur on the MXene flakes as nanoparticles in a shape of spots. The band gaps determined experimentally using Tauc's method are placed in the region of 0.90-1.31 eV. In recent years, the method of photocatalytic decomposition of pollutants using semiconductor photocatalysts and UV-vis energy has become increasingly important. The MXene based nanocomposites revealed high activity in the salicylic acid (SA) photodegradation reaction (86.1-97.1% of degraded SA after 3 h, concentration of SA initial solution 100 μM, the circulation rate of the SA solution 0.875 cm 3 /min). The interfacial charge transfer mechanism and the role of the metallic and metal oxide nanoparticles in the photocatalytic activity of the MXene based nanocomposites are presented and discussed.

Removal of lead ions from aqueous solutions, in the presence and in absence of commercial TiO 2 , under UV-light was studied. The influence of catalyst mass, concentration of Pb(II) ions and of citric acid in the starting solution as well as the impact of illumination conditions on the removal rate were also investigated. The results were fitted on the pseudo-first order, pseudo-second order and Elovich kinetic models, Weber-Morris intraparticle and liquid film diffusion models, in order to establish the photoreduction mechanism. The Pb removal rate increased in time by a combined linear-exponential mechanism. The catalyst had a positive influence on the removal rate at the start of the photoreduction. At a low concentration of Pb(II) ions (20 mg/L), the amount of photoreduced Pb(II) ions was proportional to the concentration of the citric acid solution, but at high concentrations (240 mg/L), the correlation was inversely proportional. The rate limiting steps in the removal of lead were both the photoreduction on the TiO 2 surface and the diffusion through the film surrounding the catalyst particle. The lead removal was significantly influenced by the mobility and by the concentration of the species in solution.