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[Display omitted] • Size and type of MWCNTs have a crucial impact on the Bi-based composite properties. • Enhancement of the composite photoactivity depends on the type of carbon nanotubes. • Multifunctional role of ionic liquid: reagent, template and dispersion agent. The use of various types of multi-walled carbon nanotubes in the synthesis of bismuth oxybromide semiconductors via imidazolium ionic liquid was studied in detail. The effect of the MWCNT shape, specific surface area, and various diameters on the morphology, surface properties and photoactivity of the Bi-based composites has been investigated for the first time. So far, the literature has only shown the enhancement of photocatalytic activity of composites containing MWCNT; however, our research shows a broader view of the issue. The photocatalytic activity of the individual composites under UV–Vis irradiation was assessed by the degradation of various micropollutants, showing the diversity of properties of the obtained composites. It is also significant that in the composite system, the imidazolium ionic liquid played a crucial role in the formation of microspheres and acted as a dispersing agent, leading to an even distribution of MWCNTs on the surface of the spherical bismuth oxybromide. [ABSTRACT FROM AUTHOR]

The benefits of silver nanoparticles (AgNPs) have been known in many fields from catalysis through optics to medicine due to their unique size-dependent properties. Recently, there is also a growing interest in novel skincare formulations containing AgNPs. In this work, AgNPs were successfully synthesised and were characterised by UV-Vis spectroscopy and Transmission Electron Microscopy (TEM). In addition, an analysis of particle size distribution (measured by Dynamic Light Scattering – DLS) and zeta potential (using the method Electrophoretic Light Scattering – ELS) were made. The obtained AgNPs were in two sizes: small (20 nm ± 5 nm) and large (100 nm ± 5 nm). The assessment of the cytotoxic effect on human skin cells was done. Smaller AgNPs showed less cytotoxicity and thus greater safety for skin, so they were introduced into new skincare formulations such as oil/water (O/W) emulsion, water/oil (W/O) emulsion and hydrogel. Moreover, the study of release AgNPs from emulsions and hydrogel using Franz diffusion chamber with pig skin as a membrane has been conducted. The receptor fluid measurements were performed by Atomic Absorption Spectroscopy (AAS). The last point of the research was the performance of microbiological tests to determine the antibacterial effect of the smaller AgNPs in both solution and cosmetic. [ABSTRACT FROM AUTHOR]

Highlights • The loosening of the structure and increasing the particle size of the photocatalysts due to ILs use. • ILs caused the increase of specific surface area and pore volume. • The beneficial influence of the ILs use on the energy band gap value of bismuth-based semiconductors. • ILs used as a halogen source improved the photocatalytic activity of bismuth oxyhalides. Abstract This is the first report of the effect of the ILs cation type (imidazolium, pyridinium and pyrrolidinium) on the morphology, surface properties and photoactivity of BiOX semiconductors type obtained by solvothermal method in glycerol. The various ionic liquids (IL) cation type as a halogen source and templating agent for the synthesis of the bismuth oxyhalides nanoparticles has been systematically investigated. The role of ILs in synthesis of the semiconductors was loosening of the structure and increasing the particle size of semiconductors. It was also found that ILs increased specific surface area and pore volume of bismuth oxyhalides. Rhodamine B and 5-fluorouracil were used as the model contaminates to evaluate the adsorption capacity and photooxidation performance of studied BiOX. Removal of chromium (VI) from acidic solution were demonstrated photoreduction ability of BiOX. Generally the activity of bismuth oxyhalides was better for the samples prepared with ILs, although the increase in activity was different for various ionic liquids. The changes of band gap structure were major causes of the enhanced photocatalytic activity of bismuth oxyhalides with ILs as the halogen source. [ABSTRACT FROM AUTHOR]

[Display omitted] • Highly efficient nanocomposites were obtained solvothermally. • 5-fluorouracil was oxidized major by h+ and minor by O 2 – • The roles of B:DGNW in enhancing photocatalytic activity were complex. • Cytostatic drug was effectively photooxidized in actual fresh and sea waters. • (BiO) 2 OHCl/BiOBr-1.5%B:DGNW is a promising material for water purification. In this work, a series of novel (BiO) 2 OHCl/BiOBr-x%B:DGNW (x = 0%, 1%, 1.5%, 2%) composites with different content of boron-doped diamond/graphene nanowalls (B:DGNW) were fabricated by simple solvothermal synthesis. A boron-doped diamond/graphene nanowalls (B:DGNW) were prepared by CVD method. A series of analyses: XRD, XPS, SEM, and TEM showed that the photocatalyst (BiO) 2 OHCl/BiOBr-x%B:DGNW with a "flower-like" morphology was successfully synthesized. The photocatalytic activity of the obtained composites in the degradation of 5-fluorouracil (5-FU) in various water matrices (deionized water, sea, and surface water) under the influence of artificial solar radiation was assessed. The results showed that all the prepared (BiO) 2 OHCl/BiOBr-x%B:DGNW composites were characterized by excellent photocatalytic activity. The calculated pseudo-first rate constant for 5-FU degradation increased with the elevation of amount of B:DGNW up to 1.5% in (BiO) 2 OHCl/BiOBr, and it dropped down to value obtained for non-riched material by B:DGNW, when of 2% B:DGNW was introduced to composite. The results showed that B:DGNW play a key role in the separation of charge carriers h+/e- enhancing degradation rate of 5-FU. The photoactivity of (BiO) 2 OHCl/BiOBr-1.5%B:DGNW composite to 5-FU removal was also satisfied in natural water, although its structure has changed in seawater. [ABSTRACT FROM AUTHOR]

Metal associated with urban soils are of environmental concern due to their direct and indirect effects on human health. Metallic elements in contaminated soils are absorbed by plants and undergo biomagnification in the food chain. Allotment gardens are often situated in city centers and in areas with strong anthropogenic pressure -- e.g. near industrial plants and roads. The aim of this study was to identify the bioavailable forms of metals present in urban soils. The sequential extraction procedure was applied to fractionate the following metals in urban soil samples from allotment gardens in Koszalin, Poland: chromium, copper, iron, manganese, nickel, lead, cadmium, and zinc. The mobility of the metals from studied soils decreased in the order: Cd > Mn > Pb > Zn > Ni > Cr > Cu > Fe. The sum of particular metals in the bioavailability fractions BCR I-III was: Cd 77-89%, Mn 72-81%, Pb 64-80%, Zn 54-77%, Ni 31-57%, Cr 32-53%, Cu 20-50%, and Fe 12-17%. [ABSTRACT FROM AUTHOR]

BiOX (X = Cl, Br, I) photocatalysts with dominant (110) facets were synthesized via a mannitol-assisted solvothermal method. This is the first report on the exposed (110) facets-, size-, and defects-controlled synthesis of BiOX achieved by solvothermal synthesis with mannitol. This polyol alcohol acted simultaneously as a solvent, capping agent, and/or soft template. The mannitol concentration on the new photocatalysts morphology and surface properties was investigated in detail. At the lowest concentration tested, mannitol acted as a structure-directing agent, causing unification of nanoparticles, while at higher concentrations, it functioned as a solvent and soft template. The effect of exposed (110) facet and surface defects (Bi(3−x)+, Bi4+, Bi5+) of BiOX on the photocatalytic activity of nanomaterials under the UV–Vis irradiation were evaluated by oxidation of Rhodamine B (RhB) and 5-fluorouracil (5-FU), an anticancer drug, and by reduction of Cr(VI). Additionally, the influence of crucial factors on the formation of BiOX in the synthesis with mannitol was discussed extensively, and the mechanism of BiOX formation was proposed. These studies presented a new simple method for synthesizing BiOX without any additional surfactants or shape control agents with good photocatalytic activity. The study also provided a better understanding of the effects of solvothermal conditions on the BiOX crystal growth. [ABSTRACT FROM AUTHOR]

This paper explores the connection between the H3BO3 flux concentration and the co-existence of Eu2+ and Eu3+ dopants within CaMgSi2O6 crystals (diopside). The samples were synthesised using a solid-state synthesis method under varying atmospheric conditions, including oxidative (air), neutral (N2), and reductive (H2/N2 mixture) environments. Additionally, some materials underwent chemical modification by partially substituting Si4+ with Al3+ ions acting as charge compensation defects stabilizing Eu3+ luminescence. Depending on the specific synthesis conditions, the materials predominantly displayed either the orangered luminescence of Eu3+ (under oxidising conditions) or the blue luminescence of Eu2+; however, the comprehensive results confirmed the co-existence of Eu3+/Eu2+ luminescence in both cases. This work shows that varying flux concentrations added during synthesis significantly affect the relative strength of Eu2+ and Eu3+ emissions in a manner dependent on the synthesis atmosphere. The emission of Eu2+ increases with a higher flux concentration in materials synthesised under oxidative and neutral atmospheres independent of the chemical modification. In contrast, for materials obtained under a reductive atmosphere, the changes in the Eu3+ emission intensity depended on the presence or absence of Al3+ ions namely the increase of flux increased the Eu3+ intensity in the case of unmodified materials and decreased in the Al-modified ones. All observed effects were qualitatively explained considering the double role of the flux in the studied system, which besides facilitating the diffusion of chemical species during synthesis acts as a charge compensating agent by creating B'Si centres stabilizing Eu3+ emission. [ABSTRACT FROM AUTHOR]

The paper presents the first terrestrial record of millennial-scale palaeo-ice margin oscillations at the southern fringe of the last Fennoscandian Ice Sheet (FIS) during the last glacial cycle. The study area is located in northern Poland close to the last FIS maximum limit. The chronology and dynamics of palaeo-ice margin oscillations at the southern fringe of the FIS are based on combined luminescence and 10 Be surface exposure dating. Optically stimulated luminescence (OSL) was used to date sandy deposits (fluvioglacial sediments and aeolian deposits filling fossil periglacial wedges) intercalating basal till layers. The most likely age of the tills was constrained by Bayesian modelling of the sequence of OSL ages and lithostratigraphy. 10 Be surface exposure dating was used on erratic boulders left during the final retreat of the last FIS and resting on the surface of glacial landforms. Our results, which are mainly based on OSL chronology and Bayesian modelling, indicate millennial-scale oscillations of the last FIS in northern Poland between ∼19 and ∼17 ka. The last FIS retreated and re-advanced over a relatively short period of time (2–3 ka), leaving lithostratigraphic records (basal tills) of three ice re-advances over a millennial-scale cycle: 19.2±1.1 , 17.8±0.5 and 16.9±0.5 ka. Despite 10 Be surface exposure ages obtained for 14 erratic boulders being poorly clustered, the main mode of age distribution occurs at ∼18 ka and indicates a possible signal of the ice sheet retreat after one of the re-advances. We explore the dynamics of these oscillations and compare the proposed cycles of the southern FIS advances and retreats with existing patterns of the last deglaciation and millennial-scale fluctuations of the last FIS inferred from marine records. [ABSTRACT FROM AUTHOR]

In this publication, a new dispersive solid-phase extraction (dSPE) method combined with gas chromatography-mass spectrometry and atomic absorption spectrometry was developed for the simultaneous determination of 9 PAHs and chromium, cadmium, and lead ions in water samples. For this purpose, non-modified multi-walled carbon nanotubes (MWCNTs) and modified -MWCNTs (OH-MWCNTs and COOH-MWCNTs) were used as sorbents. Parameters affecting the extraction, such as the amount of sorbent, the pH of the sample, the composition and volume of eluents and the extraction time were optimized. Sequential elution was applied using 6 mL of dichloromethane for the elution of PAHs and 5 mL of 3 M HNO 3 for cadmium, lead, and chromium. The optimal values of other parameters were as follows: 50 mg of sorbent per 250 mL of water sample, pH in a range from 6 to 7 and 30 min of contact time between the sorbent and analytes. The results demonstrated the high extraction capability of modified MWCNTs with recoveries between 80 and 101% for cadmium, chromium, and lead ions and between 83 and 92% for PAHs. Finally, the optimized method was validated, and the matrix effects were determined. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) have attracted much attention for their unique physicochemical properties, which can be designed as needed by altering the ion combinations. Besides experimental work, numerous computational studies have been concerned with prediction of physical properties of ILs. The results of molecular dynamics simulations of ILs depend strongly on the proper force field parameterization. Classical force fields and the force fields designed specifically for ILs have been found to yield diffusion coefficients, that are too low for the liquid state. This has been attributed to the lack of electronic polarizability in the most force fields. One simple solution to this problem has been uniform by scaling down of the partial charges of all ions. In this work we investigated the influence of the charge scaling, the size of the simulated system and the temperature factor on calculated density, radial distribution function and the diffusion coefficients of the cation and anion of two methylpyridinium based ionic liquids: 1-butyl-4-methylpyridinium tetrafluoroborate ([b4mpy][BF 4 ]) and 1-butyl-4-methylpyridinium chloride ([b4mpy][Cl]). We show that the parameterization is the key for a proper reproduction of the diffusion coefficient and as a consequence the melting temperature and ionic conductivity. We were also able to get some structural informations on the cation-anion relationships in the investigated ILs. [ABSTRACT FROM AUTHOR]

• BiOCl1.3Br0.7 effectively removed IMA and 5-FU singly and in their mixture. • Inorganic anions has significant effect on IMA adsorption at BiOCl1.3Br0.7. • IMA and inorganic anions significantly inhibited the 5-FU removal. • Holes mainly participated in drugs degradation, but not its mineralization. • Toxicity decreased after photodegradation of IMA and 5-FU singly and in mixture. The photocatalytic activity of series of BiOCl n Br m photocatalysts toward degradation and mineralization of the cytostatic drugs 5-fluorouracil (5-FU) and imatinib mesylate (IMA) both singly and in their mixture under simulated solar and visible light irradiation has been investigated. Screening test revealed that among BiOCl n Br m photocatalysts synthesized by a solvothermal method, the one with molar 1.3Cl/0.7Br ratio was the most efficient in 5-FU removal under UV–Vis irradiation. The dose 200 mg L−1 and 6.3 pH were optimal to effective removal of 5-FU. The BiOCl1.3Br0.7 was successfully used to 5-FU and IMA removal singly and in their mixture under simulated solar and visible light irradiation. Scavenging experiments showed that h+ and •O 2 − were the major oxidative species participated in both drugs degradation. In presence of IMA, 5-FU removal was significantly depressed. In singly drug solutions and in the mixture of drugs, the presence of inorganic ions such as Cl−, SO 4 2−, and NO 3 − significantly hindered 5-FU photocatalytic degradation, and increased the adsorption of IMA onto the photocatalyst surface in dark phase. The HCO 3 − anion, Fe3+ and Ag+ cations accelerated the 5-FU removal, while Ca2+ showed no impact on the process. The transformation products of 5-FU and IMA were identified by LC-MS revealing that hydroxylation and oxidation were the main transformation pathways, under the all studied systems. Some of intermediates were indicated for the first time in heterogeneous photocatalysis. The defluorination of 5-FU by the reaction with photogenerated e− was also possible. Furthermore, the alga toxicity assay was investigated using Chlorella vulgaris. A reduction of toxicity in effluents after photocatalytic degradation of both drugs singly and in their mixture was observed. [ABSTRACT FROM AUTHOR]

[Display omitted] Effective methods of water and wastewater purification are still being investigated. Among several methods, sorption onto carbon nanotubes (CNTs) is very promising solution. CNTs possess high potential to remove a wide range of chemicals from water, including pharmaceuticals, which are frequently found in various aqueous samples. Crucial aspect of the application of CNTs as adsorbents is the possibility to use the material multiple times with the material maintaining its sorption potential and capacity. For this reason, thermal and chemical regeneration of Multi-Walled Carbon Nanotubes (MWCNTs) was investigated in our study. The conditions of thermal regeneration were set at 300 °C for 2 h. Higher temperatures caused large losses of MWCNTs. Next, the adsorbent was put in a cycle of contamination – regeneration, where it was mixed with wastewater treatment plant influent for 16 h, then dried and thermally regenerated. After thermal treatment, the sorption level (%) of three anticancer drugs — cyclophosphamide, ifosfamide and 5-fluorouracil — was determined. The obtained results proved that there was no negative influence on the sorption level of any investigated pharmaceuticals after 5 cycles of contamination – thermal regeneration. An additional regeneration method of MWCNTs with 3 M HNO 3 was proposed, but the sorption level of cyclophosphamide after such treatment decreased from around 50 % (for untreated and thermally regenerated MWCNTs) to around 30 %. It suggests that contact with acid changed MWCNTs, probably by introducing additional functional groups onto their surface. The performed elemental analysis, Raman spectroscopy and both SEM and TEM images, confirm these predictions. [ABSTRACT FROM AUTHOR]

Carnivorous plants are exemplary natural sources of secondary metabolites with biological activity. However, the therapeutic antimicrobial potential of these compounds is limited due to intrinsic resistance of selected bacterial pathogens, among which Pseudomonas aeruginosa represents an extreme example. The objective of the study was to overcome the intrinsic resistance of P. aeruginosa by combining silver nanoparticles (AgNPs) with secondary metabolites from selected carnivorous plant species. We employed the broth microdilution method, the checkerboard titration technique and comprehensive phytochemical analyses to define interactions between nanoparticles and active compounds from carnivorous plants. It has been confirmed that P. aeruginosa is resistant to a broad range of secondary metabolites from carnivorous plants, i.e., naphthoquinones, flavonoids, phenolic acids (MBC = 512 µg mL−1) and only weakly sensitive to their mixtures, i.e., extracts and extracts' fractions. However, it was shown that the antimicrobial activity of extracts and fractions with a significant level of naphthoquinone (plumbagin) was significantly enhanced by AgNPs. Our studies clearly demonstrated a crucial role of naphthoquinones in AgNPs and extract interaction, as well as depicted the potential of AgNPs to restore the bactericidal activity of naphthoquinones towards P. aeruginosa. Our findings indicate the significant potential of nanoparticles to modulate the activity of selected secondary metabolites and revisit their antimicrobial potential towards human pathogenic bacteria. [ABSTRACT FROM AUTHOR]

In this study, biochars (BCs) produced from crops (straw and seeds) were tested for the applicability as additive to soils. The effect on pH, water capacity and cation exchange capacity of soil were tested. The ability for the sorption of pharmaceuticals (beta-blockers, anti-inflammatory drugs, sulfonamides, 17α-ethinylestradiol, carbamazepine, caffeine) using the batch sorption test was performed, and the effect of water pH was investigated. In addition, the metals removed from the biochar was analyzed as a potential toxicity factor. The mechanism of adsorption (Langmuir, Freundlich) was tested for sulfadimetoxine. The effect of the rye-derived biochar on water cress germination and the reduction of the sulfonamides toxicity to this plant was tested. The advantages of crop-derived biochar application to different soils (sand soil, clay soil and reference soil) was presented. It was found that tested BCs effectively increase the water capacity of soils, especially sand type soil, but in the same time it had increase the pH of pure-buffering soils. The driving force of pharmaceutical sorption was its ionization form - the highest sorption occurs for cations, medium for neutral forms, while the lowest sorption for anions. The opposite situation have been noted for desorption from biochar. The washing of biochars increases sorption for the neutral and anionic species, but not for the cations. The application of biochars into the soils can from one site protect the plants from toxic impact of sulfonamides, but from the other hamper the root prolongation by the pH increase. Image 1 • Crop-derived biochar show sorption toward cationic pharmaceuticals. • The mechanism of sulfonamides sorption was checked. • The amendment of soil by biochar decrease the toxicity of sulfonamides to cress. • The toxic effect of biochar to cress by the pH increase was observed. [ABSTRACT FROM AUTHOR]

The recirculating split-flow batch reactor with a cell divided into anolyte and catholyte compartments for oxidation mixture of cytostatic drugs (CD) was tested. In this study, kinetics and mechanisms of electrochemical oxidization of two mixtures: 5-FU/CP and IF/CP were investigated. The order of the CD degradation rate in single drug solutions and in mixtures was found to be 5-FU < CP < IF. In the 5-FU/CP mixture, kapp of 5-FU increased, while kapp of CP decreased comparing to the single drug solutions. No effect on the degradation rate was found in the CP/IF mixture. The presence of a second drug in the 5-FU/CP mixture significantly altered mineralization and nitrogen removal efficiency, while these processes were inhibited in IF/CP. The experiments in the different electrolytes showed that •OH and sulphate active species can participate in the drug's degradation. The kapp of the drugs was accelerated by the presence of Cl− ions in the solution. Chlorine active species played the main role in the production of gaseous nitrogen products and increased the mineralisation. Good results were obtained for the degradation and mineralisation processes in mixtures of drugs in municipal wastewater-treated effluent, which is beneficial from the technological and practical point of view. [ABSTRACT FROM AUTHOR]