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The morpho-structural, environmental and photocatalytical characteristics of Ag-graphene-TiO2 composite recovered from an used polylactic acid (PLA)-based film in comparison with those of the new prepared composite are reported. The recovered Ag-graphene-TiO2 composite displayed color, consistence, appearance, homogeneity and dispersion of nano-Ag similar with the new prepared compound. The FTIR spectroscopy showed that the oxygen and silver`s contents were 7 wt% higher in the recovered composite in comparison with the new prepared composite. The gap energy (Eg) of the recovered composite is 1.4 times and 2.3 times lower than that of new composite and TiO2, respectively. The anatase`s content decreased by 70% during the recovering, while that of rutile rised with the same magnitude. The photocatalytic activity of the recovered composite decreased only by 30% in comparison with the new composite. Additionally, the Life-Cycle Analysis (LCA) showed that the recovering procedure had a considerably lower environmental impact than the preparation of the new composite in terms of human health, ecosystem quality, climate change and resources. In conclusion, the recovering of the nanostructed composites from the active PLA-based films should be promising way to imporve the waste management.

Traditional biscuits are considered products with poor nutritional value because of their large share of rapidly digested starch, which results in an elevated glycaemic index. This paper explores the improvement of the nutritional value of biscuits by adding yellow mealworm (Tenebrio molitor) powder. Four biscuit recipes containing 0%(R1), 10%(R2), 15%(R3), and 20%(R4) of yellow mealworm powder were prepared and subjected to sensorial analysis. The R3 biscuits were selected for further investigation, as they had the highest acceptability. Compared to the reference R1, the R3 biscuits showed an improved nutritional profile in terms of protein, fat, ash, minerals, fibres, essential amino acids, and unsaturated fatty acids, and lower amounts of carbohydrates and 5-hydroxymethylfurfural. The in vitro protein digestibility in R3 improved 1.12-fold compared to R1. No significant difference was found between the digestibility of the lipids released from R1 and R3. A higher fraction of slowly digestible starch was present in R3 compared to R1. The starch digestibility and estimated glycaemic index were 72.96% and 79.56% in R3, which can be compared to 78.79% and 90.14%, respectively, in R1. Due to their enhanced nutritional profile, higher bioaccessible protein fraction, and lower glycaemic index, yellow mealworm powder biscuits can be considered a more nutritious alternative to traditional biscuits.

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 Ti2C MXene and six nanocomposites consisting of the MXene modified by TiO2, Ag2O, 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 cm3/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.

The study reports obtaining, characterization and evaluation of the preservation efficacy of nano-Ag-graphene-TiO

The aim of the study was to perform dimensional, morpho-structural, mechanical and chemical characterization of four materials based on paper currently in use in Romania (RO), Italy (IT), Spain (SP) and Slovenia (SLO) designed for the temporarily wrapping of meat. SEM-EDXS, FTIR and DSC showed that RO is laminated on one side with polyethylene, SP is waxed, IT is modified with a multilayered polyethylene film and SLO is coated with hydrophobized starch. RO, IT and SLO comply with the standards of determination of density, roughness, breaking length and bending resistance. The highest content of metals found in the SP explains the highest electrical conductivity and the poor quality of the recycled material used for manufacturing. The highest values of total dissolved solids (TDS) and chemical oxygen demand (COD) resulted for SP sample expressed its water solubility and availability of migration into foodstuff. RO, IT and SLO are suitable for food packaging. In contrast, SP do not meet the requirements for safety and mechanical resistance.

The study reports obtaining, characterization and evaluation of the preservation efficacy of nano-Ag-graphene-TiO2-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.

Three active cellulose-based papers coated in chitosan (P-CH), chitosan-TiO2 (P-CH-TiO2) and chitosan-Ag/TiO2 (P-CH-Ag/TiO2), respectively were real-time aged for 6 months at 4°C, 55% relative humidity, 15 h light/9 h dark cycle and characterized in relation to plain paper (P). The reduction in the chitosan cristallinity, N-deacetylation of chitosan, degradation of cellulosic fibers and loss in the active agents (proven by SEM, FTIR, EDX techniques and physical-chemical-microbial measurements) occurred during storage explains the deterioration of the barrier and antimicrobial properties of the active papers and subsequently the decrease in their preservation efficiency. Experimental results indicate that after storage for 6 months of the clarified butter the most effective package was P-CH-Ag/TiO2 for which the lowest levels of PV (2.72 mEq O2/kg), yeasts and molds (5.8 CFU/g) and E. coli (6.12 CFU/g) counts were measured. By mathematical modeling of the evolution of the PV, E. coli, yeasts and molds experimental profiles the shelf-life of the clarified butter packed in P, P-CH, P-CH-TiO2 and P-CH-Ag/TiO2 was assessed in respect to their admitted limits to 1.6, 2, 4 and 9.3 months, respectively. At the end of storage the appearance of P-CH-Ag/TiO2 package was clean, without greasy spots, as opposed to that of P, P-CH and P-CH-TiO2, which proves its self-cleaning property.

Three active cellulose-based papers coated with chitosan (P–CH), chitosan–TiO2 nanocomposite (P–CH–TiO2) and chitosan–Ag/TiO2 nanocomposite (P–CH–Ag/TiO2), respectively, were subjected to real-time ageing for 6 months at 25 °C and 45% re humidity and characterized from a physical–chemical–antimicrobial perspective in relation to plain paper (P). Scanning electron microscopy pictures indicate a smooth morphology in the active papers, while the structure of P is rough with large pores. The fresh papers containing nanocomposites displayed enhanced barrier properties against water vapor, air and grease. The photocatalytic action of TiO2 during ageing results in the deacetylation of the chitosan layer and the degradation of cellulosic fibers with a reduction of barrier properties. Fresh P–CH–Ag/TiO2 displayed the highest value of inhibition index against yeasts and molds (95.65%), its value decreasing to 79.25% after 6-month storage. Walnut kernels were stored for 6 months at 25 °C and 45% RH in packages made of investigated papers and analyzed. It was found that P–CH–Ag/TiO2 is the most effective in the prolongation of the shelf-life of kernels. They are assessed to be safe in terms of peroxide value and yeasts and molds count for 11.6 and 15.1 months when stored in P–CH–Ag/TiO2 filled with 25 and 50 g kernels, respectively, as compared to 1.8 and 3.4 months, respectively when they are stored in P. The appearance of packages containing nanocomposites was clean without grease spots in opposition with that of P and P–CH and proves the self-cleaning property of P–CH–TiO2 and P–CH–Ag/TiO2. Cluster diagrams indicate a strong correlation between the quality and safety of kernels and properties of paper sheets in a paper type-depending manner.

The study investigates four paper-based materials designed for short-time wrapping of meat products by determining morpho-structure, capillary-hydroscopic, barrier and antibacterial properties, wettability and migration into food simulants. The paper-based materials are coded as RO, SP, IT and SLO. RO and SLO samples exhibit the best barrier properties against water vapors. The low solubility and contact angles of RO, IT and SLO in A simulant (distilled water) make them suitable for aqueous food storage. The extremely high solubility of SP and SLO in simulant B (acetic acid) shows that wax and hydrophobized starch, respectively are carried by the acidic media, thus these agents are unlikely to coat the paper designed to package acidic food. SLO inhibits E. coli, Salmonella enterica, Lysteria monocytogenes, Pseudomonas aeruginosa and fluorescens. Polyethylene coated on RO and IT surface and wax impregnated on SP have a lower antimicrobial activity in comparison with hydrophobized starch coated on SLO.

This study addresses the preparation and characterization of three active cellulose-based papers containing TiO2, Ag–TiO2 and Ag–TiO2–zeolite nanocomposites (P–TiO2, P–Ag–TiO2, P–Ag–TiO2–Z) and is aimed at use in bread packaging. It is organized in two parts: (1) the first part covers the morpho-structural characterization of nanocomposites and paper sheets (X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, energy dispersive X-ray) and explores some properties of the papers sheets (photocatalytic activity, wettability, barrier properties); (2) in the second part, the comparative efficiency of papers in the bread storage is discussed in terms of acidity, nutritional parameters (total fat, proteins and carbohydrates) and yeasts and molds charge. Morpho-structural investigations revealed a heterogeneous distribution of nanocomposites in the cellulose network as single particles or agglomerates. The higher content of active agents in the P–Ag–TiO2–Z positively affects the hydrophobicity, roughness, photocatalytic activity, opacity and water vapor permeability the most as compared to P–P (plain paper), P–TiO2 and P–Ag–TiO2. The free channels inside the zeolite structure result in the poorest barrier properties against air and grease of P–Ag–TiO2–Z and the highest food simulants–paper contact angles. Packaging tests indicate P–Ag–TiO2 as the most effective in the preservation of nutritional compounds in the bread. In return, P–Ag–TiO2–Z prolongs the microbiological safety of bread in terms of yeasts and molds content for 10 days at 20 °C and 12 days at 4 °C, 2 days longer than the second-ranked P–Ag–TiO2.

Removal of lead ions from aqueous solutions, in the presence and in absence of commercial TiO2, 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 TiO2 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.

The aim of this study was to prepare and characterize nanostructured composites based of TiO2, carbonaceus materials (GN or GO) and Ag and the test their capacity to remove the pollutants from domestic wastewater. The composites were characterized by IR and UV-Vis spectroscopy, X-ray diffraction, electron microscopy and nitrogen adsorption–desorption measurements. The photocatalytic activity was measured from the experiment of salicylic acid (SA) degradation. The capacity to remove the pollutants from domestic wastewater was performed by considering the absorbance of residual solution at 200 nm. The non-calcined composites have high specific surface area (˜300 m2/g), but nitrogen adsorption–desorption isotherms showed a porous structure with closed pores. The porosity of the thermal treated composites is about 10 times less, but the pores are open. The salicylic acid was 94% degraded over all composites, showing their efficient photoactivity. A percent of 70% of pollutants were removed over the calcined composites with GN and ˜67% on those with GO. It was no statistically significant difference between the photocatalytical efficiency of GN- and GO-based composites. Even if the calcined composites have the specific surface area about 10 times lower, their lower gap energy, higher degree of crystallinity and photocatalytic activity make them efficient candidates for removal of pollutants from domestic waste water. The photodegradation mechanism occurred mostly by π–π interactions between GN/GO and pollutant molecules.

This study explores the morpho-structure of gallstones (GSs) removed from 36 patients in NW Romania and correlate it with the laboratory results of the patients. GSs were analyzed by SEM-EDS, X-ray diffraction and IR, UV–Vis and X-ray photoelectron spectroscopy. The laboratory studies consisted in hematological, coagulation, biochemistry, immunological and tumor markers tests. The morphological and structural investigations allowed to classify the GS in five different types and to establish their mechanism of formation. Only macroscopic evaluation, SEM microscopy, FTIR and UV–Vis spectroscopy give different easily noticeable information for each GS type. EDS, XPS and XRD diffraction are recommended to distinguish pigment and carbonate stones from the other GS types and a carefully examination is needed to establish the differences between the pure cholesterol, the mixed cholesterol and the composite cholesterol stones, due to the high similarities. The variation of specific markers cannot differentiate the patients with pure cholesterol GS from those with mixed cholesterol and pigment GS and those with mixed cholesterol from those with composite cholesterol stones. Seven laboratory parameters (RDW-CV, MPV, PCT, GLUC-HK, WBC, PT, GPT) are the key indicators for the GS disease and trend to present generally higher values than normal.

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

The objective of this study was to improve the sensorial characteristics of frozen dough bread by replacing free yeast cells with calcium alginate-yeast cells (CAY) or calcium alginate–starch yeast cells (CASY) hydrogels. Alginate-starch increased encapsulation efficiency by 18.7% compared with alginate-based encapsulation. Frozen storage affected the viability of all yeast cells, particularly free yeast cells, followed by yeasts encapsulated in CAY and CASY. The sensory evaluation of bread baked from both fresh and frozen doughs revealed that the highest scores for crust color and firmness, taste, smell, and overall acceptability were awarded to bread baked using dough containing CAY-encapsulated yeast that was subjected to 3-months storage. The scores obtained for crumb texture and specific volume (3.61 and 4.5, respectively) for frozen dough bread containing CAY-encapsulated yeast were similar to the highest scores, which were awarded to bread made from fresh dough with free yeast cells (3.63 and 4.84, respectively). These results indicated that the immobilization of baker's yeast in an alginate-based hydrogel could represent a viable solution for overcoming yeast cryosensitivity, allowing for the production of frozen dough bread with improved sensorial characteristics, which would be highly acceptable by consumers and opening new avenues for the economic sector of frozen baked good products.

Green bell peppers fruits, stored for 1 month at 8oC and 455% relative humidity in Far-Red light (FRL) and darkness respectively, were investigated in terms of physical, chemical and microbiological parameters. The exposure to FRL slows down the water loss from fruits by stimulating the surface wax biosynthesis into a higher specific amount and hydrophobic nature and reducing the apertures, diameters of the pericarp cells, intercellular walls and dermal layer thicknesses. The higher level of catalase enzyme in the FRL-exposed fruits resulted in lower chilling injury index in comparison with the one in fruits exposed to darkness. FRL has favorable effect on chlorophyll and carotenoids accumulation rates. The multiplication of yeasts and molds on the surface of FRL-exposed bell peppers was significantly delayed as compared to the multiplication on the surface of the darkness-exposed bell peppers.

Six gelatin films incorporating different ratios of sage oil (SO) and hemp oil (HO) were subjected to contact with food simulants and environmental exposure, respectively, for 3 months, at 15 000 lx light intensity, 40°C and 65% relative humidity. The migration and degradation, respectively, of the antioxidants into the simulants as well as their loss in the environment were mathematically modelled. The fastest release rate of antioxidants was noticed in the case of SO : HO 0 : 2 in 85% ethanol while the highest degradation rates were achieved after 18 days in the case of SO : HO 0 : 2 in water and 3% acetic acid and after 22 days in 85% ethanol. The antioxidants from SO : HO 0 : 2 were lost to the largest extent (5.37%) while those from SO : HO 1 : 1 to the lowest extent (3.49%). SO : HO 1 : 1 was selected as the most efficient film, by optimizing the amount of antioxidants available solely for food protection with the longest stability in the simulants. From industrial point of view, the mathematical modelling of the previously mentioned processes allows for the selection of the most effective film from a group with comparable physical–chemical–microbiological properties. Copyright © 2016 John Wiley & Sons, Ltd.

Red tomatoes exposed for one month to monochromatic Far-Red Light (FRL 740 nm) and darkness, respectively at 10 °C were subjected to physical-nutritional-microbiological investigations. The stimulation of wax biosynthesis corroborated with the widening of hydrophobic fraction in the tomatoes wax composition, the narrowing of the diameter and aperture of pericarp cells in tomatoes cuticle during FRL exposure result in tighter cuticle-wax adhesion, enhanced barrier properties against transpiration and improved firmness retention. Moreover, the storage in FRL proves to be more effective as compared to that in darkness in terms of browning index, titratable acidity and ascorbic acid level. Discoloration in the skin of FRL-exposed tomatoes in the end of storage was more pronounced than that of darkness-exposed tomatoes, as result of lycopene content reduction to a greater extent. A significant diminishing in the surface colonization with yeasts and molds was observed in the FRL-exposed tomatoes as compared to those exposed in the darkness. The results are relevant both from the industrial and consumership points of view. The positive influence of FRL on attributes of red tomatoes in storage can be addressed to improve the illumination in warehouses reflected in the prolongation of tomatoes shelf life and nutritional value, reducing of food waste and financial loss.

Titania–silica composite aerogels with 16–29% Ti-content by the mass were synthesized by the sol–gel method from different Ti-precursors, and calcined at 500 °C. These aerogels are highly amorphous as no crystalline TiO 2 phase can be detected in them by X-ray diffraction methods, and show the dominating presence of either mesopores or macropores. The incorporation of Ti into the silica structure is shown by the appearance of characteristic IR transitions of Si O Ti vibrations. The characteristic band-gap energies of the different aerogels are estimated to be between 3.6 and 3.9 eV from UV reflection spectra. Band-gap energy decreases with decreasing pore-size. When suspended in solution, even these highly amorphous aerogels accelerate the photodegradation of salicylic acid and methylene blue compared to simple photolysis. Kinetic experiments were conducted under illumination, and also in the dark to study the adsorption of the substrates onto the suspended aerogels. We assume that the fast in situ adsorption of the organic substrates mask the suspended aerogel particles from UV photons, which reduces the rate of photocatalysis. We managed to mathematically separate the parallel processes of photocatalysis and adsorption, and develop a simple kinetic model to describe the reaction system.

Preparation, morpho-structural and photo-characterization of Ag/TiO2–SiO2 (0.5–1wt%) composites were reported. The silver ions were reduced on the titania–silica surface in two different routes. The best Ag/TiO2–SiO2 photocatalysts must have high specific surface area and low Ag content, when the Ag nanoparticles homogeneous dispersed onto the mixed oxide surface generates an oxidation state of titanium (TiAg4+), that improves the charge carriers transfer, thus increasing their photoactivity. A negative value of the activation energy suggested that the temperature does not influence the photoactivity of the composites.

Removal of lead ions from aqueous solutions, in the presence and in absence of commercial TiO

This study was carried out to assess the shelf life and microbiological safety of wheat bread during storage in a packaging system made of Ag/TiO2 nanocomposite (Ag/TiO2-P) in comparison with bread packed in high density polyethylene (HDP-P) and bread not subject to packaging (CS). The Ag/TiO2 nanocomposite was prepared by sol–gel procedure, and its morphostructural characterization was performed by X-ray diffraction, Fourier transform infrared spectroscopy and transmission electron microscopy. The Ag/TiO2-P was prepared via inclusion of nanocomposite between the polyethylene layers to avoid bread–nanocomposite contact. Chemical and microbial stability of bread expressed in terms of total fat, protein, sugar, lipid hydroperoxides and yeasts, moulds, and Bacillus subtilis and Bacillus cereus counts, respectively, was monitored for 6 days. Experimental data indicate that Ag/TiO2-P considerably extends the shelf life and microbiological safety of bread in comparison with HDP-P and CS. A possible mechanism involved in the preservation of the bread is hypothesized. Copyright © 2014 John Wiley & Sons, Ltd.

Metal binding by algae has enormous potential for environmental bioremediation of industrial and urban wastewater. Algae have been proven to be cheaper and more effective for the removal of metallic elements in aqueous solutions. The present work reports the use of dried filamentous green algae, Oedogonium sp., for the sorption of Cu, Co, Cr, Fe, Hg, Ni, Zn and U in single and multi-ion solutions. Algal biomass from a gold mining site in Johannesburg was used in the study. The FT-IR analysis of the biomass revealed the presence of amino, carboxyl, phosphate and carbonyl functional groups. The maximum adsorption capacity was observed between pH 2 and 5 for Cr, Cu, Ni and Zn in single-ion solutions, whereas, in multi-ion solutions, the adsorption capacity was constant for the metals studied over the pH regime from 2 to 7, except for Ni and U. The formation of the negatively charged complexes leads to the decrease of the uptake of U beyond pH 4. The equilibrium data demonstrated a good fit with the Freundlich model for both cases. The biosorption of metals on the Oedogonium sp. biomass was exothermic and spontaneous and occurred on heterogeneous surface. The Oedogonium sp. biomasses could be repeatedly used up to 3 cycles with a virtual increase of their initial adsorption capacity. More than 110% of the metals adsorbed were eluted from the biomass. These results indicate that there were metals initially adsorbed on the biomass which were also released during desorption. Thus, this study demonstrated that algal biomass could be used as an efficient biosorbent for the treatment of trace element-bearing wastewater.

Orange juice was stored in polyethylene packages containing Ag-TiO2-Fe or TiO2 composites to establish the extent to which these composites influence the physical-chemical, microbiological and organoleptic characteristics of the juice. The composites were characterized in terms of structure (X-ray diffraction, transmission electron microscopy, Fourier-transformed infrared) and photoactivity while the packages were profiled in terms of their UV-vis absorption and water vapor permeability. The acidity and the browning rate of the sample stored in the package with Ag-TiO2-Fe decreased after 10 days of storage, as compared with the sample deposited in TiO2 packages and with the reference sample (polyethylene). The microbial population in the orange juice increased after 10 days of storage in all packages, but the increase was smaller in the Ag-TiO2-Fe polyethylene package. The organoleptic properties of the fresh orange juice deposited in package with Ag-TiO2-Fe were almost identical with those of the freshly prepared sample (0 days), whereas those of the juice deposited in the reference package were unacceptable. Practical Applications The study provides evidence that the packages of polyethylene modified with Ag-TiO2-Fe can be used to store fresh orange juice for 10 days at room temperature (22.5C).

The paper explores some aspects related to the application of nanomaterials in food packaging. Therefore, the paper is structured into two sections. In the first section, aspects that could restrict/restrain the application of nanomaterials in food packaging industry in terms of environmental and human risks, the consumer`s rights to be informed regarding the utilization of nano-packages and regulation issues in the field of large scale application of food nano-packages are discussed. In the second section, the efficiency of a nano-package based on Ag/TiO2 to preserve for a longer time (6 days) the physical attributes of wheat bread (moisture, specific volume, porosity) by comparison with shorter ranges allowed by the common polyethylene bag (3 days) and non-packaging respectively (1 day) is demonstrated.

Titanium dioxide has waste applications as photocatalyst, as antimicrobial material and in biomedical field. By modifying the surface of TiO2 with noble metals its photoactivity will be enhanced. This paper aims to explain the role of the copper particles deposited on titania surface during the photodecomposition of salicylic acid and to provide evidence about which kinetic model describes best the photocatalysis. The research explains why the photodecomposition rate of salicylic acid is higher in Cu/TiO2 composite as compared to in TiO2. It consists in kinetic approach of the photocatalytic behaviour of Cu–TiO2 and TiO2, thus being possible to discuss the photodecomposition mechanism. This research will allow improvement of the techniques to remove salicylic acid from synthetic solution. This could be extended to other organic pollutants.

composites havebeen characterized using X-ray diffraction, Raman and FTIR spectroscopy techniques and TEM microscopy. The role of zeo-lite particles in the photoreduction process was demonstrated by using different kinetic models. The apparent constant ratefor photoreduction increases in direct proportion with the content of zeolite and is higher for the composites modified withFe than for those modified with Ag nanoparticles. The results demonstrate that composites have a higher photocatalytic

Methyl orange (MO), methylene blue (MB), phenol (F), salicylic acid (SA), and rhodamine B (ROD) were used as substrates during the photodegradation experiments in the absence and in the presence of nanostructured Ag/titania-silica. The catalyst was characterized by scanning electron microscopy (SEM), scanning transmission electron microscope high-angle annular dark field (STEM-HAADF), stereological analysis, nitrogen adsorption-desorption, and X-ray photoelectron spectroscopy (XPS) measurements. The results were fitted on pseudo-first and pseudo-second kinetic order models. The film diffusion was also determined. The photolysis degrades MO and F to a greater extent than the photocatalysis. The degradation of SA occurred at the same rate either by photolysis or by photocatalysis. MB was best removed by photocatalysis. With regard to the photocatalysis, the highest rates of film diffusion were obtained for MB, F, and ROD, meaning that these molecules crossed the film to arrive at the catalyst surface more rapidly than the others. For MO and MB, the results followed the pseudo-first-order kinetic model while for SA, F, and ROD, the pseudo-second-order kinetic model was more appropriate.

Summary 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.

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) ofthe SPSS software package.

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 effecton Hieracium aurantium, while both natural zeolite and zeolite modified demonstrate a significant role for Rumex acetosella, asrevealed by statistical tests.

Asarum europaeum L. contains water-soluble substances which manifest allelopathic potential. Aqueous extracts from leaves and stems of Asarum europaeum were assayed to determine their allelopathic effects on Lycopersicon esculentum and Zea mays seeds germination and early seedling growth. The germination of the investigated seeds was found to be inhibited with increasing of the Asarum europaeum L. extract concentration. Moreover, the active substances extracted from leaves were found to be more inhibitory on the seeds germination in comparison with those extracted from stems.

The key goal of our research is the identification and analysis of accumulations of metal ions (Pb2+, Zn2+, Cu2+, Fe2+) during their imbibition in seeds of Phaseolus vulgaris and Zea mays. We take as samples seeds collected from one metalliferrous and respectively from one non-metalliferrous area in Maramures County (North-West of Romania). We will refer following to an area as being “metalliferrous” because of its known high degree of pollution with metallic components, and to the other area as “non-metalliferous” because of being generally known as very much less exposed to pollution in general. We will subsequently name as being “polluted” the seeds originated in the metalliferous area, and respectively as “unpolluted” the seeds originated in the other area. We have thoroughly investigated in quantitative terms the existence of accumulations of each of the metal ions mentioned above during imbibition at three different levels of concentration. The seeds grown in the non-metalliferous area generally display a higher degree of absorption for each of the metal ions than the seeds grown in the metalliferous area. On the other hand, we have concluded that the concentration of heavy metals does not impact significantly the absorption capacity of both the polluted and unpolluted Z. mays seeds. The P. vulgaris seeds behaved differently, namely the content of metal ions absorbed went proportionally up, as the concentration of the initial solution went higher.

This study explored the distribution of different species of native and alien herbaceous species on the tailing pond Bozânta Mare (Maramureş county in NW Romania) and the differences in heavy metal uptake in the roots and shoots relative to: 1. herbaceous species; 2. differential metal uptake and variation within single-species; 3. metal content of soil substrate. In 2007-2009 the contribution of native and alien species to the herbaceous layer forming, were studied on the Bozânta Mare tailing pond, resulted after heavy metal extraction process. The heavy metals found at elevated level in the herbaceous species included for environmental interest are: Pb, Cu, Ni, Zn, Co, Cd, Fe, Cr, Mn, Na, K. Also, the aim of this research is to evaluate the impact of the native vs. alien species presence in the colonization process on the tailing pond.

Microbiological and chemical characteristics of white bread during storage in paper-packages modified with Ag/TiO2-SiO2, Ag/N-TiO2 or Au/TiO2 were investigated. The whiteness and the water retention of the modified packages were slightly superior to those exhibited by the reference sample, as the color of the composite was lighter. The water retention was very good especially for the Ag/TiO2-SiO2-paper. These improvements can be associated with the high specific surface area and with the low agglomeration tendency of Ag nanoparticles in comparison with the Au ones. The preservation activity of the composites for the bread storage is positively influenced by photoactivity and presence of nano-Ag. Packages Ag/TiO2-SiO2-paper and Ag/N-TiO2-paper can find their applicability for extending the shelf life of bread by 2 days as compared with the unmodified paper-package. No influence of the Au/TiO2 on the extending the shelf life of bread was observed.