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The X-ray absorption (XRA) method using digital image processing techniques is a reliable technique to determine the exhaustion degree of granular activated carbons (GACs). Using an innovative digital image processing technique, the identification of individual adsorbed molecules or ions in a GAC was possible. Adsorption isotherm models (Langmuir and Freundlich) were used to simulate the adsorption equilibrium data of Methylene Blue (MB), nickel, cobalt and iodine. Freundlich equation was found to have the highest value of R2 compared with Langmuir. The identification of distinctive patterns applying XRA for different adsorbed ions and molecules onto GAC was explored. It is demonstrated that unique XRA configurations for each adsorbed ion or molecule are found, as well as a proportional relationship between its incident energy (needed to achieve maximum photon attenuation) and the (effective) atomic number, the adsorbate mass and the molar or atomic mass of adsorbed molecule or ion. XRA method in combination with image histogram modifications was used to obtain a digital signature of adsorbed ions/molecules, giving distinct GSI values for each one in the used energy range. Probabilistic models prove that XRA results are within relationships between effective atomic number and photonic interaction probability, reinforcing the potentialities of XRA for monitoring (multi-)ion and/or molecule combinations on GAC using advanced digital image processing techniques. It was proved that the proposed approach could assess different adsorbed ions/molecules onto GACs in water purification systems. [ABSTRACT FROM AUTHOR]

• Acoustic emission analysis (AEA) is a sensitive technique to characterise activated carbons. • AEA can quantify the exhaustion level of the different layers in a GAC filte. • AEA is also an alternative method for nitrogen adsorption (BET analysis). • TGA, XRF and Elemental Analysis are used to validate the acoustic emission results. • AEA offers a solution for monitoring a correct management of GAC application. A new Acoustic Emission Analysis (AEA) method has been successfully applied to quantify the exhaustion degree in an industrial granular activated carbon (GAC) filter for water treatment in different industrial processes. Five samples of GAC obtained at different depths of the target industrial filter have been evaluated. For the first time the analysis of the acoustic energy and the signal power was applied, besides the processing of signal its frequency, amplitude and integral area under the signal envelope curve. The envelope and energy of the acoustic signal were mathematically processed using Gilbert and Parseval theorems. Additionally, image segmentation techniques are applied to analyze spectrograms in order to determine the exhaustion level of the GAC samples. Acoustic emission results are discussed in terms of CaCO 3 adsorption mechanisms in the water filter and correlated with dedicated analytical methods such as TGA, SEM, FTIR, XRF and N 2 gas adsorption. The implementation of AEA in engine power plants in Cuba constitutes an interesting approach to implement an improved strategy of GAC management in water treatment industries. [ABSTRACT FROM AUTHOR]

With recent advances in the field of diagnostics and theranostics, liposomal technology has secured a fortified position as a potential nanocarrier. Specifically, radiation/photo-sensitive liposomes containing photo-polymerizable cross-linking lipids are intriguing as they can impart the vesicles with highly interesting properties such as response to stimulus and improved shell stability. In this work, 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphoethanolamine (DTPE) is used as a photo-polymerizable lipid to form functional hybrid-liposomes as it can form intermolecular cross-linking through the diacetylenic groups. Hybrid-liposomes were formulated using mixtures of DTPE and saturated lipids of different chain lengths (dipalmitoylphosphatidylcholine (DPPC) and dimirystoilphosphatidylcholine (DMPC)) at different molar ratios. The physico-chemical characteristics of the liposomes has been studied before and after UV irradiation using a combination of techniques: DSC, QCM-D and solid-state NMR. The results signify the importance of a subtle modification in alkyl chain length on the phase behavior of the hybrid-liposomes and on the degree of crosslinking in the shell. [ABSTRACT FROM AUTHOR]

Abstract The removal of Ibuprofen was investigated by activated carbon impregnated with TiO 2. Emphasis was given on the effect of different parameters, such as composite type, initial Ibuprofen concentration (5–25 mg/L), temperature (22–28 °C) and pH (acidic and alkaline solution). The experiment was carried out in a self-made tubular flow reactor, with one 15 W monochromatic UV lamp (254 nm). The composite AC90T10 gives the highest removal degree of 92% of Ibuprofen solution under UV light within 4 h, due to synergy of adsorption and photodegradation. It was found that weight ratio of composite/Ibuprofen has limited effect on the removal degree within the concentration range (5–25 mg/L), but reaction time under UV light (4 h) and pH (acidic solution) are very important. The kinetic experimental data obtained at pH 4.3 at 25 °C on different composites were fitted to pseudo-first, pseudo-second and Elovich models, obtaining a high accuracy based on R2 values. From the results, composites of granular activated carbon and TiO 2 can enhance removal of Ibuprofen effectively, making recycle process much easier and less costly, which can be a promising method in future water treatment. Highlights • Three kinds of activated carbon impregnated with TiO 2 (ACT) were prepared. • Removal of Ibuprofen includes effects of adsorption and photodegradation by ACT. • ACT composites effectively improve removal of Ibuprofen under UV. • Kinetic tests of Ibuprofen removal were studied onto different composite catalysts. [ABSTRACT FROM AUTHOR]

Abstract One of the major challenges for the nuclear industry is the safe and sustainable immobilisation of radioactive wastes (RAW). Currently, the most commonly used immobilisation matrices for low and intermediate level wastes are based on ordinary Portland cement. For the more difficult to immobilise nuclides, such as caesium (Cs+) and strontium (Sr2+), researchers have been studying alternative immobilisation matrices, of which alkali-activated materials (AAM) are a very promising option. However, the differences in precursor compositions and the use of different types of activating solutions make it difficult to fully understand the effects of precursor composition on the immobilisation of introduced nuclides. Therefore, six different compositions of laboratory-synthesised Ca-Si-Al slags were developed to serve as precursors for low-alkaline AAMs to study their immobilisation behaviour. Immobilisation capacities up to 97.6% Cs+ and 99.9% Sr2+ were achieved with 1 wt% and 0.1 wt% waste loading, respectively, when leaching for 7 days at 20 °C in Milli Q water. Cs+ immobilisation is higher at lower Si/Al and Ca/(Si + Al) ratios. Immobilisation of Sr2+ is higher at a lower Ca/(Si + Al) ratio and independent of Si/Al ratio. The results of this study offer a deeper understanding of the immobilisation behaviour of AAMs and can encourage further research and application of AAMs for RAW immobilisation. Graphical abstract Image 1 Highlights • Stoichiometrically controlled Ca-Si-Al slags were designed as precursors for AAMs. • Very effective immobilisation of Cs+ (97.6%) and Sr2+ (99.9%) was achieved. • Cs+ immobilisation increases with decreasing precursor Si/Al and Ca/(Si + Al) ratios. • Cs+ is partitioned into an easily-leachable fraction and a strongly-bound fraction. • Sr2+ immobilisation increases with decreasing precursor Ca/(Si + Al) ratio. [ABSTRACT FROM AUTHOR]

For the first time, an absolute quantification of hybrid materials obtained from the reaction of phenylphosphonic acid (PPA) with TiO 2 nanoparticles under different reaction conditions is reported. Next to the amount of PPA involved in grafting to the TiO 2 nanoparticles, also the PPA included in titaniumphenylphosphonate crystallites is described quantitatively. The quantitative analysis is based on solid state 31 P MAS NMR and is further applied to evaluate the stability of the resulting hybrid materials towards hydrolysis and organic solvent exposure. [ABSTRACT FROM AUTHOR]

Surface-modified hemp stem-based activated carbons (HACs) were prepared and used for the adsorption of atrazine from aqueous solution, and their adsorption performance was examined. A series of HACs were prepared by potassium hydroxide activation of hemp stems, followed by subsequent modification by thermal annealing, oxidation with nitric acid and amination. The resultant HACs differed in surface chemistry, while possessing similar porous structure. The surface group characteristics were examined by X-ray photoelectron spectroscopy and measurement of the point of zero charge (pH). The adsorption of atrazine from aqueous solution was performed in static conditions. The Langmuir-Freundlich and Langmuir models gave a better fit for equilibrium isotherms compared with the Freundlich model. The atrazine adsorption process was controlled by an intraparticle diffusion mechanism with a significant contribution from film diffusion. The presence of oxygen and nitrogen functionalities on the carbon surface was found to be undesirable for atrazine adsorption. The superior adsorbent was obtained by heat treatment of HAC in an inert atmosphere at 700 °C, resulting in a very high adsorption capacity due to its enhanced hydrophobicity. The adsorption of atrazine on the studied HACs mainly involves π-π dispersive interactions between the atrazine ring and the graphene layers of carbon. [ABSTRACT FROM AUTHOR]

Abstract: Thermal extraction–GC–MS (TE–GC–MS) is a relatively new analytical technique which demonstrates a large potential for the analysis of various solid matrices. This technique provides a rapid quantitative and simultaneous determination of a wide range of volatile and semi-volatile organic compounds without laborious sample preparation or any chemical pre-treatment. Its amenability to automation and coupling with on-line detection methods makes TE–GC–MS a promising technique, not only in laboratory analysis, but also for in situ emission monitoring. However, the number of studies dedicated to the application of TE–GC–MS to fly ashes, which are an unavoidable by-product of any thermal industrial process and also the sink of many environmental pollutants, is limited. The ability of TE–GC–MS to analyse a wide range of trace semi-volatile dioxin surrogate compounds in fly ash samples is investigated as an alternative to the well-established solvent extraction–GC–MS analysis (SE–GC–MS). Reproducibility, the effect of TE temperature, time, flow, and the influence of the analysed matrix are studied. Dedicated experiments demonstrate that the conversion (dechlorination and in situ formation) of target analytes and the decomposition of the fly ash matrix can take place at elevated TE temperatures and during prolonged TE times. Moreover, these effects are matrix-specific and vary from sample to sample. After optimizing the TE parameters, two fly ash samples of different origins are analysed and more than 50 individual analytes representing different classes of aromatic compounds are quantified and compared with those available from the SE–GC–MS analysis. [Copyright &y& Elsevier]

Thermogravimetric analysis (TGA) has been combined with evolved gas analysis (EGA) with the purpose of simulating the thermal behaviour of filter dust samples under inert (desorption) and de novo test oxidising conditions. Emphasis is on studying de novo formation of dioxins, surrogates and precursors arising from filter dust derived from thermal processes, such as municipal solid waste incineration and metallurgy. A new method is tested for sampling and analysing dioxin surrogates and precursors in the TGA effluent, which are collected on sampling tubes; the adsorbed compounds are eventually desorbed and quantified by TD-GC–MS. The major sources of error and losses are considered, including potential sorbent artefacts, possible breakthrough of volatiles through sampling tubes, or eventual losses of semi-volatiles due to their incomplete desorption or re-condensation inside the TG Analyser. The method is optimised and validated for di- to hexa-chlorinated benzenes in a range of 10–1000ppb with average recovery exceeding 85%. The results are compared with data obtained in similar studies, performed by other research groups. As a result, the method provides the means for simulating de novo synthesis of dioxins in fly-ash and facilitates reliable and easy estimation of de novo activity, comparable with results of other studies, in combination with wide flexibility of testing conditions. [Copyright &y& Elsevier]

Different resol phenol–formaldehyde prepolymer resins have been synthesized with different Formaldehyde/Phenol (F/P) ratios or different catalysts and characterized by 13C NMR spectroscopy in solution. A fast quantitative measuring protocol is proposed based on the use of chromium(III)acetylacetonate as a relaxation agent. APT (attached proton test) and DEPT (distortionless enhancement by polarisation transfer) spectra were acquired to enable proper resonance assignments, especially in the regions with severe signal overlap. Equations are presented in which the methylene bridges (MB), the methylol groups (MG) and the dimethylene ether bridges (DMEB) of resol resins are quantitatively taken into account. Important structural factors determined quantitatively for resol prepolymer resins are the F/P ratio after reaction, the degree of polymerization (n), the number average molecular weight (Mn) and the content of free ortho and para positions. [Copyright &y& Elsevier]

Since polycyclic aromatic hydrocarbons (PAHs) are mutagenic, teratogenic, and carcinogenic, they are of considerable environmental concern. A biotechnological approach to remove such compounds from polluted ecosystems could be based on the use of white-rot fungi (WRF). The potential of well-adapted indigenous Ganoderma strains to degrade PAHs remains underexplored. Seven native Ganoderma sp. strains with capacity to produce high levels of laccase enzymes and to degrade synthetic dyes were investigated for their degradation potential of PAHs. The crude enzymatic extracts produced by Ganoderma strains differentially degraded the PAHs assayed (naphthalene 34—73%, phenanthrene 9—67%, fluorene 11—64%). Ganoderma sp. UH-M was the most promising strain for the degradation of PAHs without the addition of redox mediators. The PAH oxidation performed by the extracellular enzymes produced more polar and soluble metabolites such as benzoic acid, catechol, phthalic and protocatechuic acids, allowing us to propose degradation pathways of these PAHs. This is the first study in which breakdown intermediates and degradation pathways of PAHs by a native strain of Ganoderma genus were determined. The treatment of PAHs with the biomass of this fungal strain enhanced the degradation of the three PAHs. The laccase enzymes played an important role in the degradation of these compounds; however, the role of peroxidases cannot be excluded. Ganoderma sp. UH-M is a promising candidate for the bioremediation of ecosystems polluted with PAHs. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) belong to the most commercialized nanomaterials, used in both consumer products and medical applications. Despite its omnipresence, in-depth knowledge on the potential toxicity of nanosilver is still lacking, especially for developing organisms. Research on vertebrates is limited due to ethical concerns, and planarians are an ideal invertebrate model to study the effects of AgNPs on stem cells and developing tissues in vivo, as regeneration mimics development by triggering massive stem cell proliferation. Our results revealed a strong interference of AgNPs with tissue- and neuroregeneration which was related to an altered stem cell cycle. The presence of a PVP-coating significantly influenced toxicity outcomes, leading to elevated DNA-damage and decreased stem cell proliferation. Non-coated AgNPs had an inhibiting effect on stem cell and early progeny numbers. Overall, regenerating tissues were more sensitive to AgNP toxicity, and careful handling and appropriate decision making is needed in AgNP applications for healing and developing tissues. We emphasize on the importance of AgNP characterization, as we showed that changes in physicochemical properties influence toxicity. [ABSTRACT FROM AUTHOR]

Raman spectroscopy and micro-Raman mapping have been used to study the distribution of different chemical components at the surface of coated papers. The paper coatings contain organic nanoparticles with a structure of poly(styrene-co-maleimide) and encapsulated vegetable oils. Raman spectroscopy is able to differentiate between various types of oil, i.e., polyunsaturated, monounsaturated, or saturated, and indicates that the degree of imidization and reactivity of the oil (amount of free oil) complement each other. The surface mapping over large areas (5 × 5 mm2) illustrates good homogeneity of the coating layer and even surface coverage. The imide and oil are homogeneously distributed within the coating itself without a tendency for agglomeration. The covered areas of imide and oil mostly overlap for polyunsaturated oils, while larger amounts of oil occur outside the imide zones for monounsaturated and saturated oils. The latter indicates that the oil is partly "free" within the coating and acts as a continuous binder phase. The surface mapping over smaller areas (1 × 1 mm2) shows the coating and cellulose covered areas are complementary. The surface maps confirm that interaction between the coating and paper substrate happens through hydrogen bonding. Heterogeneities in the coating are due to the presence of remaining ammonolyzed maleic anhydride precursors forming amic acid moieties. The organic phase, oil phase, and cellulose substrate can also be differentiated by principal component analysis of the surface maps. [ABSTRACT FROM AUTHOR]

Comprehending the decomposition process is crucial for our understanding of the mechanisms of carbon (C) sequestration in soils. The decomposition of plant biomass has been extensively studied. It revealed that extrinsic biomass properties that restrict its access to decomposers influence decomposition more than intrinsic ones that are only related to its chemical structure. Fungal biomass has been much less investigated, even though it contributes to a large extent to soil organic matter, and is characterized by specific biochemical properties. In this study, we investigated the extent to which decomposition of heathland fungal biomass was affected by its hydrophobicity (extrinsic property) and melanin content (intrinsic property). We hypothesized that, as for plant biomass, hydrophobicity would have a greater impact on decomposition than melanin content. Mineralization was determined as the mineralization of soil organic carbon (SOC) into CO2 by headspace GC/MS after inoculation by a heathland soil microbial community. Results show that decomposition was not affected by hydrophobicity, but was negatively correlated with melanin content. We argue that it may indicate that either melanin content is both an intrinsic and extrinsic property, or that some soil decomposers evolved the ability to use surfactants to access to hydrophobic biomass. In the latter case, biomass hydrophobicity should not be considered as a crucial extrinsic factor. We also explored the ecology of decomposition, melanin content, and hydrophobicity, among heathland soil fungal guilds. Ascomycete black yeasts had the highest melanin content, and hyaline Basidiomycete yeasts the lowest. Hydrophobicity was an all-or-nothing trait, with most isolates being hydrophobic. [ABSTRACT FROM AUTHOR]

Minimizing harmful effects to the environment in waste-management practices requires continuous innovation. This is especially important in the field of radioactive waste management. Alternatives to the commonly used ordinary Portland cement matrices are being increasingly studied for improved immobilisation purposes. The development of inorganic polymers (IP) from industrial residues has been successfully studied for the immobilisation of caesium (Cs + ) and strontium (Sr 2+ ). However, knowledge of the effect of these introduced elements on the IP-matrix is scarce, especially considering that studied effects are dependent on the IP-precursor characteristics and the form in which the Cs + and Sr 2+ are introduced. In this study, IPs containing varying amounts of CsNO 3 and Sr(NO 3 ) 2 were developed to study the effect of the introduced elements on the IP-characteristics. IP-samples were developed from ground granulated blast furnace slag (GGBFS) and 6 M NaOH activating solution. Cs + and Sr 2+ were added to account for 0.5, 1 and 2 wt% of the total IP-mass. Throughout the entire study, Cs + -addition showed no significant effects on the studied parameters. Calorimetric results showed that Sr 2+ severely affects reaction kinetics, consuming hydroxide ions necessary for the alkali activation reaction. Sr 2+ -addition also caused a severe decrease in compressive strength, increased calcium leaching, and decreased sodium and hydroxide leaching. Micro-chemical analyses showed that Cs + is almost fully incorporated in the formed IP-matrix, while Sr 2+ mainly precipitates as Sr(OH) 2 in concentrated regions throughout the IP-structure. The findings presented in this paper give insights on the effect of contaminant elements on the immobilising matrix. [ABSTRACT FROM AUTHOR]

Lignites from Thrace- and Sofia- coal basins, i.e. “Maritsa-East” and “Stanjanci” mines, were subjected to aqueous sequential extraction at 25 °C during 10 weeks. Each 7 days leachates were separated and pH and conductivity were measured. According to the extraction curves μS vs. time two portions were prepared, enriched in salts, extracts from the first two weeks (“front” of the elution) and in organic matter, extracts from the rest of time (“tail” of the elution curve). Combined freeze-dried extracts were characterized by yields, technical and elemental analyses. They were studied by X-ray photoelectron spectroscopy (XPS) and Infrared spectroscopy (IR). According to XPS spectra the main species on the leachate surfaces were carbon atoms in aromatic and aliphatic structures, 48–53 at. % from the total C1s signal. The intensive N1s signal at 400 eV was assigned to pyrroles and amines (1–3 at. %). The most abundant sulphur form was inorganic sulphates while intensities for the other ones were < 1%. Respectively, the sulphatic sulphur content (13.6%) determined for Maritsa leachate was almost seven times higher than the same sulphur for Stanjanci leachate. FTIR spectra gave evidences for oxygen-containing functional groups, i.e. COOH groups in benzene carboxylic acids and their derivatives, in short-chain aliphatic fatty acids and for polyols. The appearance of mineral matter, mainly gypsum and kaolinite, made equivocal the IR spectra interpretation. Acetone soluble portions of “tail” leachates have represented relatively small parts of the organic matter (340 mg/kg Maritsa East and 80 mg/kg Stanjianci lignite) but have assigned reliable evidences for the polar constituents of leachates. Linear fatty acids, n C 12 – n C 32 , n C 16 max , n -alcohols, benzoic acids, i.e. hydroxy-, methoxy-, phthalic acids, were highly abundant. Sterols, stanols, ketosterols were present in both extracts. Phthalates were recognizable as well. AP-TPR-TD-GC/MS technique has proved the presence of phenols, PAHs and heteroatom containing components in leachates flue gases. From an environmental viewpoint it seems that the identified compounds do not represent an acute toxic risk. However, N-containing compounds could raise concerns and further attention is needed to be focused on them. [ABSTRACT FROM AUTHOR]

The effects of different atmospheres on the distribution of organic and inorganic sulphur compounds during high-pyrite coal pyrolysis were investigated. Sulphur compound releases were determined by atmospheric pressure-temperature programmed reduction (AP-TPR) “on-line” coupled with MS and AP-TPR “off-line” coupled with TD-GC/MS, which is a reliable technique for coal sulphur characterization. The results show that the decomposition of both organic and inorganic sulphur is different in the three applied atmospheres: H 2 , N 2 and CO 2 . In H 2 , most sulphur from LZ coal is hydrogenated/reduced to H 2 S, decomposition of inorganic sulphur (pyrite and sulphates) has a great effect on the formation of H 2 S. It not only enhances the intensity of its m / z 34 signal but also shifts the peak maximum of its profile to a higher temperature, even without a returning to the base line. In inert N 2 gas, as expected, hydrogenation of some sulphur compounds such as less-reactive di-aryl sulphur species and simple thiophenic structures are highly limited. The dominant peak of m / z 34 can also be related to the reduction of pyrite. In CO 2 , coal sulphur is mainly converted into SO 2 /SO, because CO 2 is a more reactive gas and rather acts as an oxidizing agent. Decomposition of organic sulphonic acids occurs before 500 °C and of sulphonics/sulphoxides after 500 °C. The decomposition of sulphates and pyrite is better detectable in CO 2 than in inert gas atmosphere. After 800 °C char gasification in CO 2 results in further decomposition of sulphur compounds and lower sulphur retention. [ABSTRACT FROM AUTHOR]

The microwave assisted reaction between P25 titanium dioxide (TiO 2 ) and phenylphosphonic acid (PPA) is explored thoroughly and the influence of the reaction conditions on the grafting mechanism and formed products is presented. While the surface grafting is observed at low temperatures and water free conditions, the formation of titaniumphosphonate is favored in water and high reaction temperatures. For the first time the correlation between the amorphous TiO 2 phase and the formation of titaniumphenylphosphonate is reported. Materials are fully characterized by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), solid-state 31 P Nuclear Magnetic Resonance ( 31 P NMR) spectroscopy, energy dispersive X-ray (EDX) spectroscopy and transmission electron microscopy (TEM). [ABSTRACT FROM AUTHOR]

Hybrid materials are being developed to add organic functionalities to inorganic materials. Here, titanium dioxide is modified with organophosphonic acids (PAs). In several applications, the surface properties of the material play a key role in their performance (e.g. separation, sorption, catalysis). Hence, the surface properties of these materials need to be specifically adjusted to meet the requirements of each application (e.g. in membrane separation or chromatography). As the synthesis conditions have an important influence on the obtained surface properties, it is necessary to understand the impact and differences introduced by altering synthesis conditions. Different solvents are being applied for modification, but a comparative study of the impact of this change in environments is missing in literature. Therefore, our aim is to study the impact of concentration, temperature and pH in water and toluene on the properties of TiO 2 modified with propylphosphonic acid (3PA). By combining complementary techniques (DRIFT, TGA and 31 P/CP MAS NMR), clear differences induced by the solvent can be found. Moreover, in toluene a lower concentration of 3PA is required to obtain closed packed monolayers than in water. Furthermore, both solvent and concentration are influencing the modification degree and binding type formed on the surface. Moreover, only in water, next to the concentration, also the temperature and pH have a strong impact on the binding type of 3PA. A clear difference in thermal stability of 70 °C was found between both binding types. [ABSTRACT FROM AUTHOR]

The effects of CO 2 atmosphere on the distribution of volatile organic sulphur compounds during coal pyrolysis and the effect of kaolin addition were studied. Sulphur compounds release was determined by atmospheric pressure-temperature programmed reduction “on-line” coupled with MS (AP-TPR/MS) and “off-line” coupled with GC/MS after thermal desorption (AP-TPR-TD-GC/MS). The results show that thiophene and methyl and ethyl substituted analogues were released between 400 and 500 °C, while relatively more complex organic sulphur compounds such as benzothiophene and methyl benzothiophene evolved at higher temperature. In CO 2 , thiophenes evolved at lower temperature due to its more reactive and oxidative character. With kaolin addition, an increase in most registered volatile organic sulphur compound amounts was noticed both in inert and CO 2 gas, due to the catalytic effect of kaolin. [ABSTRACT FROM AUTHOR]

Acoustic analysis and sound patterns recognition techniques have been widely used in many branches of science, however; almost none focused on the characterization of granular activated carbon. A new methodology has been developed in order to characterize activated carbon based on the dynamic analysis in audible spectra of the sound’s relative amplitude power produced by water flooded on granular activated carbon. A home-build recording set-up and management of acoustic measurements have been presented and correlated with the results of porous structure of carbons characterized by N 2 adsorption. Five samples of granular activated carbons used in the rum production of different exhausted level have been evaluated by both methods. Parameters as the BET surface area and total pore volume showed a satisfactory correlation with acoustic measurement data when the signal is processed at 1000 Hz. Three frequencies components of the produced sound were analyzed and related with the porous characteristics. The found relationship gives the possibility to predict and calculate textural parameters of granular activated carbons applying the acoustic technique. This methodology approach opens possibilities in using acoustic experiments for the characterization of high-porosity materials and to determine their exhausted level. [ABSTRACT FROM AUTHOR]

Atmosphere Pressure–Temperature Programmed Reduction (AP–TPR) technique coupled “off-line” with thermal desorption gas chromatography–mass spectrometry (TD-GC/MS) can be effectively used to specify qualitatively/quantitatively organic functionalities in humic substances. The AP–TPR technique has been initially developed and successfully applied for sulphur speciation in coals and in their biodesulphurized products. The aim of the present study is to analyze volatiles in flue gases of a reductive pyrolysis of Miocene-aged lignite humic acids by AP–TPR “off-line” TD-GC/MS and to assign identified components to the structural compositions of the samples studied. Humic acids from two coal-bearing provinces in Bulgaria, i.e. Thrace and Sofia, have been considered. The following compounds were tracked and quantified in the flue gases released during the AP–TPR experiments: aliphatics, i.e. n C 6 – n C 14 , mono unsaturated/saturated pairs, alkylated benzenes, styrenes, naphthalenes, biphenyls, fluorene, acenaphthylene; oxygen containing compounds, i.e. phenols, methoxy phenols, furans, benzofurans; sulphur containing compounds, i.e. sulphides, thiophenes, benzothiophenes; nitrogen containing compounds, i.e. pyrroles, indoles, quinolines, benzonitriles, etc. Total content of organics in pyrolysates amounts to 55.9 mg/g C org for Thrace humic acids (Maritza-East deposit) and 55.0 mg/g C org for Sofia humic acids (Stanjanci deposit). Alkyl benzenes (C 6 –C 10 ) highly dominate in the programs up to half of the recorded components (46–58 rel.%). The low sample maturity is reflected in high abundance of phenols, C 6 –C 8 (20 rel.%), methoxy phenols (2.7 rel.%) and degradation products from carbohydrates, i.e. furaldehydes, 2-cyclopenten-1-ones, etc. Plots of four group composites, i.e. aliphatics, aromatics, O-, S- and N-containing compounds, in “spider web” diagram seem promising for bulk interpretation of pyrolysates data. According to the reductive pyrolysis data, structural units of Miocene-aged humic acids are composed by 1–2 aromatic rings, condensed or coupled, including heteroatoms arranged in linear and cyclic forms. [ABSTRACT FROM AUTHOR]

A novel class of polystyrene-based gel-type resins (SPACeR, SP), containing the large 1,4-bis(4-vinylphenoxy)benzene cross-linker, is introduced; SP-immobilized 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) and triethylamine (TEA) bases are synthesized and characterized in terms of their structural, thermal and morphological features, and their catalytic efficiency in a series of fundamental chemical transformations under solvent-free conditions is investigated. [ABSTRACT FROM AUTHOR]

The main barrier in the commercialization of phytoextraction as a sustainable alternative for remediating metal contaminated soils is its long time period, which can be countered by biomass valorization. From an environmental point of view, fast pyrolysis of the biomass is promising because its lower process temperature prevents metal volatilization. The remaining question is whether fast pyrolysis is also preferred from an economic point of view. Therefore, a techno-economic assessment of fast pyrolysis has been performed for a case study in the Campine region in Belgium. For this region, willow trees cultivated in short rotation have the right characteristics to serve as a phytoextracting crop. A techno-economic assessment requires by definition a multidisciplinary approach. The problem statement urges for a focus on the economic profitability from the viewpoint of an investor, including economic risk analysis. Fast pyrolysis seems more profitable than gasification. The profit is dependent on the scale of operation, the policy support (subsidies) and the oil yield. The economic risk can be reduced by increasing the scale of operation by means of complementing feedstocks, and by valorization of the char byproduct by subsequent processing to activated carbon. [ABSTRACT FROM AUTHOR]

Background and aims: Numerous microorganisms have been isolated from trinitrotoluene (TNT)-contaminated soils, however TNT tends to persist, indicating that the microbial biomass or activity is insufficient for degradation. Deep-rooting trees at military sites have been found to take-up contaminants from groundwater, and the extensive root and endosphere provide ideal niches for microbial TNT-transformations. Methods: We characterised the rhizosphere, root endosphere and endo-phyllosphere bacteria of Acer pseudoplatanus growing at a historically TNT-contaminated location, using 16S rRNA gene fingerprinting, bacteria isolation, oxidoreductase gene-cloning, in planta growth-promotion (PGP) tests, inoculation, plant physiology measurements and microscopy. Results: Based on terminal-restriction-fragment-length-polymorphism analysis, bulk soil and rhizosphere samples were highly clustered. Proteo- and Actinobacteria dominated the rhizosphere and root endosphere, whereas Alphaproteobacteria were more abundant in shoots and Actinobacteria in leaves. We isolated multiple PGP-bacteria and cloned 5 flavin-oxidoreductases belonging to the Old Yellow Enzyme family involved in TNT-reduction from 3 Pseudomonas spp., the leaf symbiont Stenotrophomonas chelatiphaga and the root endophyte Variovorax ginsengisola. Conclusions: The inoculation with a selection of these strains, consortium CAP9, which combines efficient TNT-transformation capabilities with beneficial PGP-properties, has the ability to detoxify TNT in the bent grass ( Agrostis capillaris) rhizosphere, stimulate plant growth and improve plant health under TNT stress. [ABSTRACT FROM AUTHOR]

This study aims to uncover the spatiotemporal involvement of glutathione (GSH) in two major mechanisms of cadmium (Cd)-induced detoxification (i.e. chelation and antioxidative defence). A kinetic study was conducted on hydroponically grown Arabidopsis thaliana (L. Heyhn) to gain insight into the early events after exposure to Cd. Cadmium detoxification was investigated at different levels, including gene transcripts, enzyme activities and metabolite content. Data indicate a time-dependent response both within roots and between plant organs. Early on in roots, GSH was preferentially allocated to phytochelatin (PC) synthesis destined for Cd chelation. This led to decreased GSH levels, without alternative pathways activated to complement GSH's antioxidative functions. After one day however, multiple antioxidative pathways increased including superoxide dismutase (SOD), ascorbate (AsA) and catalase (CAT) to ensure efficient neutralization of Cd-induced reactive oxygen species (ROS). As a consequence of Cd retention and detoxification in roots, a delayed response occurred in leaves. Together with high leaf thiol contents and possibly signalling responses from the roots, the leaves were protected, allowing them sufficient time to activate their defence mechanisms. [ABSTRACT FROM AUTHOR]

Ocular chitosan films were prepared in order to prolong ocular delivery of cyclosporine A. The mucoadhesive films were prepared using the solvent casting evaporation method. A 24 full factorial design was used to evaluate the effect of 4 preparation parameters on the film thickness, swelling index and mechanical properties. Moreover, uniformity of content and in vitro drug release were investigated. Possible interactions between the film excipients were studied by FTIR analysis. In vitro experiments were performed in order to evaluate the cytotoxicity and anti-inflammatory activity of the chitosan films. Film thickness, water uptake, mechanical properties and in vitro release of cyclosporine A were dependent on film composition, especially on the amount of plasticizer. Lower drug release was measured from chitosan films containing a higher amount of plasticizer as glycerol decreased the swelling of chitosan films. FTIR spectra suggest a reorganization of hydrogen bonds between chitosan chains in the presence of glycerol and cyclodextrins. None of the film formulations showed significant cytotoxicity as compared to the negative control using human epithelial cells (HaCaT). Cyclosporine A dispersed in the various film formulations remained anti-inflammatorily active as significant suppression of interleukin-2 secretion in concanavalin A stimulated Jurkat T cells was measured. [ABSTRACT FROM AUTHOR]

The aim of the study is to increase the bioavailability of itraconazole (ITRA) using nanosized cocrystals prepared via wet milling of ITRA in combination with dicarboxylic acids. Wet milling was used in order to create a nanosuspension of ITRA in combination with dicarboxylic acids. After spray-drying and bead layering, solid state was characterized by MDSC, XRD, Raman and FT-IR. The release profiles and bioavailability of the nanococrystalline suspension, the spray-dried and bead layered formulation were evaluated. A monodisperse nanosuspension (549±51nm) of ITRA was developed using adipic acid and Tween®80. Solid state characterization indicated the formation of nanococrystals by hydrogen bounds between the triazole group of ITRA and the carboxyl group of adipic acid. A bioavailability study was performed in dogs. The faster drug release from the nanocrystal-based formulation was reflected in the in vivo results since T max of the formulations was obtained 3h after administration, while T max of the reference formulation was observed only 6h after administration. This fast release of ITRA was obtained by a dual concept: manufacturing of nanosized cocrystals of ITRA and adipic acid via wet milling. Formation of stable nanosized cocrystals via this approach seems a good alternative for amorphous systems to increase the solubility and obtain a fast drug release of BCS class II drugs. [ABSTRACT FROM AUTHOR]

Abstract: Treatment and/or disposal of metal contaminated biomass are still an unsolved problem. Knowledge of the metal distribution is of prime importance concerning the application of pyrolysis product streams. Sorghum bicolor (L.) Moench was cultivated in a semi-hydroponic system to assess its potential use in phytoremediation and biomass production. Plants were grown in a greenhouse using perlite as substrate, half-strength Hoagland's solution as control (CTR) and the same solution supplemented with a mixture of Ni and Zn (CTM; 10 g m−3 each). Shoot and root biomass were determined and analyzed for their metals content. Flash and slow pyrolysis were performed on S. bicolor shoots at 450 °C. Biomass and pyrolysis products were analyzed focusing on metal distribution. Mass and energy balances were determined. S. bicolor delivered good shoot biomass with relatively moderate concentrations of Ni and Zn. Metal concentrations in the pyrolysis oils were below detection limits and almost all metals accumulated in the char. In fact, 99% of Ni and 98% of Zn were recovered in the char when a slow pyrolysis process was applied, while in flash pyrolysis conditions both metals were found back in the char and in the heating transfer medium. Furthermore, the percentages of char and oil were higher in slow pyrolysis compared to flash pyrolysis. Energy recovery in the char from slow pyrolysis was higher than flash pyrolysis. Flash and slow pyrolysis can likely offer a valuable processing method for metal contaminated biomass, thus limiting the waste disposal problem associated with phytoremediation of metals. [Copyright &y& Elsevier]

Hybrid titania phosphonate materials can demonstrate a high added value as tailored sorption materials. They combine high chemical stability with great structural versatility, given the wide diversity of functional groups that can be incorporated. Hereto, a fundamental understanding of the synthesis strategies influencing the material performance is required. Therefore three porous TiO 2 phosphonate hybrid structures with different functional groups (octyl, propyl, and phenyl) were evaluated in a solid-phase extraction application aimed towards solvent separation. The synthesis was performed by mixing bridged diphosphonic acids (DPAs) with Ti(OBu) 4 in a water-ethanol mixture at 30 °C, followed by a hydrothermal post-treatment at 120 °C. The materials were characterized by ICP-AES, 31P solid-state CP/MAS NMR, Raman and FTIR spectroscopy, X-ray diffraction, N 2 -sorption, and transmission electron microscopy. It is shown that the diphosphonic acids are quantitatively incorporated in the hybrid structures, leading to nanosized particles with a complex but uniquely functionalized surface. A study of the pore structure as a function of the incorporated DPA amount showed materials with a maximum BET surface area of 379 m2/g. The alkyl functionalized hybrid titania phosphonates demonstrated excellent and tunable sorption behavior. [Display omitted] • Porous Hybrid Titania phosphonates are hydrothermally prepared without template. • Incorporation of a diphosphonic acid group enhances porosity. • Material characteristics are heavily dependent on incorporation rate. • Solvent separation efficiency is highest for alkyl-modified materials. [ABSTRACT FROM AUTHOR]

Abstract: Polymethacrylates such as Eudragit® polymers are well established as drug delivery matrix. Here, we synthesize several Eudragit E PO (n-butyl-, dimethylaminoethyl-, methyl-methacrylate-terpolymer) analogues via free radical polymerization. These polymers are processed via hot melt extrusion, followed by injection molding and evaluated as carriers to produce immediate release solid solution tablets. Three chemical modifications increased the glass transition temperature of the polymer: (a) substitution of n-butyl by t-butyl groups, (b) reduction of the dimethylaminoethyl methacrylate (DMAEMA) content, and (c) incorporation of a bulky isobornyl repeating unit. These structural modifications revealed the possibility to increase the mechanical stability of the tablets via altering the polymer T g without influencing the drug release characteristics and glassy solid solution forming properties. The presence of DMAEMA units proved to be crucial with respect to API/polymer interaction (essential in creating glassy solid solutions) and drug release characteristics. Moreover, these chemical modifications accentuate the need for a more rational design of (methacrylate) polymer matrix excipients for drug formulation via hot melt extrusion and injection molding. [Copyright &y& Elsevier]

Abstract: Chars from fast and flash pyrolysis of different short rotation hardwoods are activated by steam or KOH, resulting in a variety of activated carbons (ACs). Analysis of nitrogen adsorption isotherm shows that microporous ACs are obtained. Density functional theory calculation is applied to obtain information concerning the micropore size distribution. Additionally, methylene blue (MB) and iodine adsorption experiments are performed to evaluate the AC adsorptive properties. The textural and adsorptive properties are compared with a commercial AC (Norit). KOH activation yields ACs with very high surface area, micropore volume and adsorption capacity, while steam activation promotes formation of narrower micropores but yields less pore volume. The MB adsorption kinetics can be described by the pseudo-second-order model, and most ACs adsorb at least 70% of their maximum MB adsorption capacity within 15min. [Copyright &y& Elsevier]

Abstract: Zinc (Zn) is an essential micronutrient for plants, but accumulation of excess Zn causes oxidative stress, even though the element is not redox-active. An oxidative stress signature, consisting of multiple oxidative stress related parameters, is indicative of disturbance of redox homeostasis and signaling, but has not been determined after exposure to excess Zn. To reveal general and Zn-specific effects, changes in oxidative stress related gene expression, enzyme activities and metabolites were determined after 24h exposure of Arabidopsis thaliana plants to a concentration range of 0, 100, 250 or 500μM excess ZnSO4, and the oxidative stress signature compared to the ones reported previously for cadmium or copper exposure in the same experimental system. Zn accumulated in both roots and leaves, which led to a disturbed redox homeostasis as evident from increased H2O2 levels and altered glutathione redox state. In roots, magnesium uptake was affected and glutathione levels decreased due to reduced glutathione reductase activity and increased phytochelatin production. In leaves, mRNA levels of all chloroplast-localized superoxide dismutases (SOD) were downregulated, indicating that the converse regulation by Cu availability of FeSOD (FSD) and Cu/ZnSOD genes (CSDs) was disturbed. Furthermore, an opposite stress-dependent transcriptional regulation of the different loci of a miRNA species was observed: excess Zn repressed primary transcripts of the MIR398a gene, but increased MIR398b and MIR398c transcription. Also, accumulation of mRNA was inhibited for CSD2, but stimulated for CSD1. MiR398 has been reported to downregulate CSD1 and CSD2 mRNA. Here, the opposite effect on CSD1 and CSD2 mRNA accumulation under Zn stress in the leaves could be explained if CSD1 in the leaves would be regulated exclusively by miR398a, and not by miR398b/c under these conditions. The results support the existence of Zn-specific signal transduction pathways influencing anti-oxidative responses and are useful as a starting point for genetic screens identifying upstream metal-specific sensing and signaling mechanisms. [Copyright &y& Elsevier]

Abstract: The aim was to evaluate near-infrared spectroscopy for the in-line determination of the drug concentration, the polymer–drug solid-state behaviour and molecular interactions during hot-melt extrusion. Kollidon® SR was extruded with varying metoprolol tartrate (MPT) concentrations (20%, 30% and 40%) and monitored using NIR spectroscopy. A PLS model allowed drug concentration determination. The correlation between predicted and real MPT concentrations was good (R 2 =0.97). The predictive performance of the model was evaluated by the root mean square error of prediction, which was 1.54%. Kollidon® SR with 40% MPT was extruded at 105°C and 135°C to evaluate NIR spectroscopy for in-line polymer–drug solid-state characterisation. NIR spectra indicated the presence of amorphous MPT and hydrogen bonds between drug and polymer in the extrudates. More amorphous MPT and interactions could be found in the extrudates produced at 135°C than at 105°C. Raman spectroscopy, DSC and ATR FT-IR were used to confirm the NIR observations. Due to the instability of the formulation, only in-line Raman spectroscopy was an adequate confirmation tool. NIR spectroscopy is a potential PAT-tool for the in-line determination of API concentration and for the polymer–drug solid-state behaviour monitoring during pharmaceutical hot-melt extrusion. [Copyright &y& Elsevier]

Abstract: Practically it is extremely difficult to collect observations following a fully sound statistical design, typically encompassing a high number of repetitions, of an intensive and elaborate experimental procedure such as flash pyrolysis reactor experiments. Pyrolysis–gas chromatography/mass spectrometry (Py–GC/MS) is an extremely useful analytical technique in order to simulate a high number of repetitive pyrolysis experiments in an acceptable time span. Combining Py–GC/MS experiments and statistical data processing, conclusions can be drawn on the pyrolysis behaviour of any input material, supplying crucial information on its respective behaviour during the actual flash pyrolysis experiments. In this research Py–GC/MS experiments combined with a tailored statistical data processing methodology strongly indicate the occurrence of synergetic interactions during the flash co-pyrolysis of willow/polyhydroxybutyrate (PHB) blends. Such interactions are also indicated by pattern recognition and by the analysis of the condensable and noncondensable pyrolytic gases obtained from Py–GC/MS. Accordingly, the actual influence of the flash co-pyrolysis of willow and PHB, executed with a semi-continuous pyrolysis reactor, on the pyrolytic oil features is investigated by GC/MS. Based on these experiments an explanation for the observed synergy during flash co-pyrolysis of willow and PHB is proposed. [Copyright &y& Elsevier]

Abstract: Contaminated soil particles and food are established routes of exposure. We investigated the relations between biomarkers of exposure to cadmium and lead, and the metal loading rates in house dust in the adult residents of an area with a soil cadmium concentration of ⩾3mg/kg () and a reference area (). We determined the metal concentrations in house dust allowed to settle for 3 months in Petri dishes placed in the participants’ bedrooms. The continuously distributed vegetable index was the first principal component derived from the metal concentrations in six different vegetables. The biomarkers of exposure (blood cadmium 9.2 vs. 6.2nmol/L; 24-h urinary cadmium 10.5 vs. 7.0nmol; blood lead 0.31 vs. 0.24μmol/L), the loading rates of cadmium and lead in house dust (0.29 vs. 0.12 and 7.52 vs. 3.62ng/cm2/92 days), and the vegetable indexes (0.31 vs. −0.44 and 0.13 vs. −0.29 standardized units) were significantly higher in the contaminated area. A two-fold increase in the metal loading rate in house dust was associated with increases () in blood cadmium (+2.3%), 24-h urinary cadmium (+3.0%), and blood lead (+2.0%), independent of the vegetable index and other covariates. The estimated effect sizes on the biomarkers of internal exposure were three times greater for house dust than vegetables. In conclusion, in the adult population, house dust is potentially an important route of exposure to heavy metals in areas with contaminated soils, and should be incorporated in the assessment of health risks. [Copyright &y& Elsevier]

The atmospheric pressure temperature programmed reduction (AP-TPR) technique, an approach for organic sulphur speciation, was extended by mass spectral detection. The coupling gave ground for precise assignment of sulphur compounds in flue gases of lignite lithotypes pyrolyzed in H2 atmosphere. A broad range of sulphur compounds was determined, i.e. thiols, dimethylsulphide, dimethyldisulphide, CS2, thiophenes, benzothiophenes and their alkylated homologues. Certain peculiarities in organic sulphur distribution in lithotypes under study were noticed. Humovitrain was the lithotype with the highest organic sulphur content. A preponderance of aliphatic sulphur, thiols and dimethylsulfides were determined for both homogeneous lithotypes (xylain and humovitrain). In humovitrain, additionally thiophenes were also identified. For heterogeneous lithotypes, liptain and humoclarain, a dominance of disulphides and an almost lack of sulphides was observed. This is an indication that with coalification a gradual loss of aliphatic sulphur functions has proceeded, where more resistant disulphides sulphur bridges turned out to be present. Thiophenes are the most abundant aromatic structures, dominating in humoclarain. Some amounts of oxidised organic sulphur compounds (1% up to 4.1% of Sorg) were semi-quantitative determined in lithotypes using AP-TPR-MS. [Copyright &y& Elsevier]

This article describes the vibrational evidence of reversible and irreversible phase transitions, observed in some simple amides RHNCOCONHR (R=alkyl or hydroxyethyl) and RHNCOCOOH (R=cyclopropyl). [Copyright &y& Elsevier]

[Display omitted] • A new non-invasive methodology using infrared thermography on activated carbon. • An accurate analytical alternative for characterization and monitoring is discussed. • Infrared thermography data correlate with exhaustion level of activated carbons. • Infrared thermography results correlate with outcome of dedicated analytical methods. • Infrared thermographic parameters correlate with surface area and pore volumes. A new non-invasive methodology based on infrared thermography (IRT) to evaluate the exhaustion level of granular activated carbon (GAC) at different depths of a target industrial water treatment filter is studied. IRT results are discussed in terms of adsorption capacity and correlated with dedicated analytical methods: N 2 gas adsorption, TGA, TD-GC/MS and NMR. Findings revealed that the surface temperature and surface thermal density parameters are contingent with the exhaustion level as well as the surface area and pore volumes of the GAC samples. Surface temperature decreased with 80% and the surface thermal density with 35% comparing exhausted Top-GAC and virgin GAC. Linear correlation was found between IRT parameters and the exhaustion profile of 98%. During GAC exploitation the surface area was reduced to 85% and the total volume of pore to 80%. The IRT method demonstrated to be simple and accurate and suitable for GAC management of water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ivy is a promising biomass feedstock for pyrolysis based biorefinery processes. • A pyrolysis temperature of 400 °C yields high-quality biochars. • Ethanol extractions increase biochar carbon sequestration potential by 20 %. • Steam distillations improve biochar's carbon content (12 % at 700 °C). Hedera helix L., the common ivy, is an excellent evergreen climbing plant to be applied in vertical green walls to improve urban ecosystems. These green walls need to be trimmed regularly, yielding a biomass stream, which could be promising as a renewable feedstock for biochar production and the extraction of valuable chemicals. The potential of raw and spent (extracted) common ivy as a biochar feedstock was evaluated using slow pyrolysis at different temperatures: 400, 550 and 700 °C. Biochars produced at 400 °C showed a high carbon, nitrogen and ash content, while still having residual surface functionalities. These biochars are therefore interesting to be applied as soil fertilizer. Additionally, it was found that the impact of different green extraction processes (ethanol extraction versus steam distillation) before pyrolysis on the biochar properties was generally positive. Ethanol extractions increased biochar yields and the fraction of inorganic nutrients. Furthermore, ethanol extractions increased the carbon sequestration potential compared to raw ivy. Steam distilled biochar exhibited a very high carbon content (83 %), biochar stability (97 %) and aromaticity (100 %). Steam distillation did not affect the carbon sequestration potential. In conclusion, this investigation affirms common ivy as a promising feedstock for pyrolysis based biorefinery processes. [ABSTRACT FROM AUTHOR]