Wood - a renewable resource for production of sugar and biofuel

Albies Alba wood samples were subjected to autohydrolysis extraction at different severities (180, 190 and 200°C), delignification with sodium chloride, and acid hydrolysis of pretreated and delignified substrates. After autohydrolysis pre-treatment under selected operation conditions, cellulose and lignin, in solid phases, and liquors containing hemicellulose products (monosaccharides, oligosaccharides and inhibitory compounds) have been obtained. The purpose of this study is to obtain glucose by autohydrolysis, delignification and acid hydrolysis of fir wood. Fir wood was pretreated at 180, 190 and 200 °C for 5, 10 and 15 minutes, followed by delignification with sodium chloride and acid hydrolysis. The acid hydrolysis of pretreated material and pretreated-delignified material was hydrolyzed using H2SO4 in two stages of impregnation with acid. The results show that elimination of hemicellulose by autohydrolysis pretreatment and lignin by delignification method improve acid hydrolysis yield

Applying of multivariate analysis to study the correlation of mercury and other trace elements distribution in soil from a city from NW Romania

The mercury (Hg) concentrations were evaluated in soils and perennial plants from four districts of Baia Mare city, a historical mining and ore processing center from NW Romania. The results showed that in 24% of the analysed soil samples the mercury concentrations exceeded the guideline value of 1.0 mg kg'1, established by the Romanian Legislation, while the median concentration was 0.70 mg kg'1, bellow the guideline values, but higher than the normal values for soil and the mean or median concentration in soils from other cities all over the world. In the perennial plants, the median concentration was 0.22 mg kg'1, value that exceed the maximum level of Hg (0.10 mg kg'1) established by European Directive 2002/32/EC for animal feed in order to prevent its transfer and further accumulation in the higher levels of food chain. Poor correlations were found between Hg and other elements such as As, Cd, Cu, Pb and Zn known as pollutants resulted from non-ferrous smelting activities, probably due to the different physicochemical properties of Hg that lead to a different dispersion patter compared to other metals emitted by the two smelters

Assessing the bioavailability and translocation efficiency of mineral elements in Lycium barbarum species from R. Macedonia and R. China

Goji berries or wolfberries (Lycium barbarum L.) have been traditionally used as food and a medicinal plant. The interest in the chemical composition of goji berries has intensified because of an increased awareness of their possible health benefits. On the other hand, the toxic elements can also be interacting in the plant tissue through the bioavailable pathway of the root-soil system. The present work reports the results obtained by the proposed method for the simultaneous determination of metals (Na, Mg, K, Ca, Mn, Fe, Cu and Zn) and nonmetals (P and S) in goji berries by using inductively coupled plasma–optical emission spectrometry (ICP-OES), following digestion using a diluted oxidant mixture in a closed-vessel microwave oven. Determinations of Cr, As, Pb, Cd and Ni were realized using the graphite furnace atomic absorption spectrometer (GFAAS). Mercury quantification was realized on the solid samples by the TDAAS method, with the automated direct mercury analyzer hydra-C. The obtained data for element contents reports the multi-element characterization of different plant parts, and variation in multi-elements content between Macedonian and Chinese species. Bioaccumulation and bioconcentration factor scores revealed the translocation efficiency of metals and nonmetals across the Lycium barbarum plant parts

ASSESSMENT OF Pb, Cd, Cu AND Zn AVAILABILITY FOR PLANTS IN BAIA MARE MINING REGION

In order to evaluate the mobility of heavy metals in soil from Baia Mare mining region, the total, water and DTPA extractable metal contents were determined. The results showed that despite the high total metals contents and the high percentages of plant available metals only a low percent was water soluble, indicating a potential accumulation of metals in trophic chain and a potential risk for public health. Among the investigated metals, the plant available Pb and Cd species are the most severe contaminants. Significant correlations between total and DTPA extractable metals were found for Cu (r=0.510) and Pb (0.418), and also an affinity between total and water extractable metals were identified for Cu (0.366), Pb (0.502) and Zn (0.597)

Biodegradation studies of polylactic acid copolymers

Medium molecular weight copolymers were synthesized by the condensation of L-lactic acid (LA), terephthalic acid (TPA) and 1,3-propanediol (PDO). The obtained copolymers were characterized for acid value, hydroxyl value and number average molecular weight. Also, the biodegradation behavior by different fungal species (A spergillus niger, A spergillu s versicolor, A lternaría altern a ta and P enicilliu m ) was performed. The degree of biodegradation was examined by weight loss. It was observed that the biodegradation of copolymer with higher quantity of lactic acid was faster and more effective than the biodegradation of copolymer with smaller quantity of lactic acid

Progress, Challenges and Opportunities in Divalent Transition Metal-Doped Cobalt Ferrites Nanoparticles Applications

Engineered nanomaterials with tailored properties are highly required in a wide range of industrial fields. Consequently, the researches dedicated to the identification of new applications for existing materials and to the development of novel promising materials and cost effective, eco-friendly synthesis methods gained considerable attention in the last years. Cobalt ferrite is one of the nanomaterials with a wide application range due to its unique properties such as high electrical resistivity, negligible eddy current loss, moderate saturation magnetization, chemical and thermal stability, high Curie temperature and high mechanical hardness. Moreover, its structural, magnetic and electrical properties can be tailored by the selection of preparation route, chemical composition, dopant ions and thermal treatment. This chapter presents the recent applications of nanosized cobalt ferrites doped or co-doped with divalent transition ions such as Zn2+, Cu2+, Mn2+, Ni2+, Cd2+ obtained by various synthesis methods in ceramics, medicine, catalysis, electronics and communications

Rapid Determination of Trace Elements in Macedonian Grape Brandies for Their Characterization and Safety Evaluation

A graphite furnace atomic absorption spectrometry (GFAAS) was used for determination of trace elements (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in Brakija^ samples, a grape brandy traditionally produced in Republic of Macedonia by distillation of grape pomace or wine, for characterization and safety evaluation. Cd, Pb, Cr, and Ni were determined directly, while Cu, Fe, Mn, and Zn were quantified after appropriate dilution. The calibration curves of all elements were linear with correlation coefficients (R 2 ) ranging from 0.9995 to 0.9998. The accuracy of the method was checked with a standard addition method showing good repeatability and reproducibility (relative standard deviation (RSD) <10 %). Relationship between several metal concentrations (Cu, Fe, Mn, Zn) in brandies and distillation system (homemade/industrial) on one side and aging mode (oak barrels/oak chips) on the other side were demonstrated. Two homemade brandies showed Cu, Fe, and Zn concentrations higher than industrial distillates and thus were found to be not safe for consumption because of Cu and Zn over the maximum allowed values. For the industrially produced brandies, Mn was identified to be a suitable marker related to aging with oak chips regardless variety, while Cu a marker for the influence of oak chip type

Environmental and socioeconomic assessment of impacts by mining activities—a case study in the Certej River catchment, Western Carpathians, Romania

Background, aim and scope: In the region of the Apuseni Mountains, part of the Western Carpathians in Romania, metal mining activities have a long-standing tradition. These mining industries created a clearly beneficial economic development in the region. But their activities also caused impairments to the environment, such as acid mine drainage (AMD) resulting in long-lasting heavy metal pollution of waters and sediments. The study, established in the context of the ESTROM programme, investigated the impact of metal mining activities both from environmental and socioeconomic perspectives and tried to incorporate the results of the two approaches into an integrated proposition for mitigation of mining-related issues. Study site: The small Certej catchment, situated in the Southern Apuseni Mountains, covers an area of 78km2. About 4,500 inhabitants are living in the basin, in which metal mining was the main economic sector. An open pit and several abandoned underground mines are producing heavy metal-loaded acidic water that is discharged untreated into the main river. The solid wastes of mineral processing plants were deposited in several dumps and tailings impoundment embodying the acidic water-producing mineral pyrite. Methods: The natural science team collected samples from surface waters, drinking water from dug wells and from groundwater. Filtered and total heavy metals, both after enrichment, and major cations were analysed by inductively coupled plasma optical emission spectroscopy (ICP-OES). Major anions in waters, measured by ion chromatography, alkalinity and acidity were determined by titration. Solid samples were taken from river sediments and from the largest tailings dam. The latter were characterised by X-ray fluorescence and X-ray diffraction. Heavy metals in sediments were analysed after digestion. Simultaneously, the socioeconomic team performed a household survey to evaluate the perception of people related to the river and drinking water pollution by way of a logistic regression analysis. Results and discussion: The inputs of acid mine waters drastically increased filtered heavy metal concentrations in the Certej River, e.g. Zn up to 130mg L−1, Fe 100mg L−1, Cu 2.9mg L−1, Cd 1.4mgL−1 as well as those of SO4 up to 2.2g L−1. In addition, river water became acidic with pH values of pH 3. Concentrations of pollutant decreased slightly downstream due to dilution by waters from tributaries. Metal concentrations measured at headwater stations reflect background values. They fell in the range of the environmental quality standards proposed in the EU Water Framework Directive for dissolved heavy metals. The outflow of the large tailing impoundment and the groundwater downstream from two tailings dams exhibited the first sign of AMD, but they still had alkalinity. Most dug wells analysed delivered a drinking water that exhibited no sign of AMD pollution, although these wells were a distance of 7 to 25m from the contaminated river. It seems that the Certej River does not infiltrate significantly into the groundwater. Pyrite was identified as the main sulphide mineral in the tailings dam that produces acidity and with calcite representing the AMD-neutralising mineral. The acid-base accounting proved that the potential acid-neutralising capacity in the solid phases would not be sufficient to prevent the production of acidic water in the future. Therefore, the open pits and mine waste deposits have to be seen as the sources for AMD at the present time, with a high long-term potential to produce even more AMD in the future. The socioeconomic study showed that mining provided the major source of income. Over 45% of the households were partly or completely reliant on financial compensations as a result of mine closure. Unemployment was considered by the majority of the interviewed persons as the main cause of social problems in the area. The estimation of the explanatory factors by the logistic regression analysis revealed that education, household income, pollution conditions during the last years and familiarity with environmental problems were the main predictors influencing peoples' opinion concerning whether the main river is strongly polluted. This model enabled one to predict correctly 77% of the observations reported. For the drinking water quality model, three predictors were relevant and they explained 66% of the observations. Conclusions: Coupling the findings from the natural science and socioeconomic approaches, we may conclude that the impact of mining on the Certej River water is high, while drinking water in wells is not significantly affected. The perceptions of the respondents to pollution were to a large extent consistent with the measured results. Recommendations and perspectives: The results of the study can be used by various stakeholders, mainly the mining company and local municipalities, in order to integrate them in their post-mining measures, thereby making them aware of the potential long-term impact of mining on the environment and on human health as well as on the local econom