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Kinetic, isotherm and thermodynamics investigation on adsorption of divalent copper using agro-waste biomaterials, Musa acuminata, Casuarina equisetifolia L. and Sorghum bicolor

, G.M., Chen, L., Deng, J.H., Zhang, X.R. & Niu, Q.Y. (2012). Copper (II) removal by pectin–iron oxide magnetic nanocomposite adsorbent. Chem. Eng. J. 185, 100–107. DOI: 10.1016/j.cej.2012.01.050. 21. Li, K., Fu, S., Zhan, H., Zhan, Y. & Lucia, L. (2010). Analysis of the chemical composition and morphological structure of banana pseudo-stem. Bioresources 5(2), 576–585. DOI: 10.15376/biores.5.2.576-585 22. Firdous, R. & Gilani, A.H. (2001). Changes in chemical composition of sorghum as influenced by growth stages and cultivar. Asian Australas. J

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Aqueous biological graphene based formulations for ink-jet printing

Res. 4(7), 675–684. DOI: 10.1007/s12274-011-0123-z. 3. Jangho, K., Kyoung, S.C., Yeonju, K., Ki-Tack, L., Hoon, S., Yensil, P., Deok-Ho, K., Pill-Hoon, C., Chong-Su, C., Soo, Y.K., Yun-Hoon, C. & Jong, H.C. (2013). Bioactive effects of graphene oxide cell culture substratum on structure and function of human adipose-derived stem cells. J. Biomed. Mater. Res. Part A. 101(12), 3520–3530. DOI: 10.1002/jbm.a.34659. 4. Carrow, J.K. & Gaharwar, A.K. (2015). Bioinspired Polymeric Nanocomposites for Regenerative Medicine. Macromol. Chem. Phys. 216(3), 248

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Effect of extraction method on the antioxidative activity of ground elder (Aegopodium podagraria L.)

their use. Guide to selected species. Rzeszów, Polska: Procapathia. 13. Kunstman, P., Wojcińska, M. & Popławska, P. (2012). Podagrycznik pospolity ( Aegopodium podagraria L.) Post Fitot . 4, 244–249. 14. Orav, A., Viitak, A. & Vaher, M. (2010). Identification of bioactive compounds in the leaves and stems of Aegopodium podagraria by various analytical techniques. Procedia Chem . 2, 152–160. DOI: 10.1016/j.proche.2009.12.022. 15. Priori, N.M., Lundgaard, N.H., Light, M.E., Stafford, G.I., van Staden, J. & Jäger, A.K. (2007). The polyacetylene

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Metals uptake behaviour in Miscanthus x giganteus plant during growth at the contaminated soil from the military site in Sliač, Slovakia

Abstract

Peculiarities of metals uptake by the biofuel crop Miscanthus x giganteus were explored during plant growth at soil from the military site (Sliač, Slovakia). The experiment was carried out in greenhouse during two vegetation seasons. Research soil was predominantly elevated in Fe and Ti, while other metals (As, Cu, Mn, Sr, Zn and Zr) were presented at order of magnitude lower concentrations. No inhibition of plant growth was observed. The calculated Bioconcentration Factor showed that levels of metals’ accumulation by plant roots, stems and leaves were independent of metals’ concentrations in the soil. The accumulation of metals by stems and leaves was much lower than by roots. As, Zr, Ti were almost not accumulated by stems and leaves during both seasons; accumulation of Cu, Fe, Mn, Zn and Sr was not essential which confirmed that biomass of M. x giganteus might be processed for the energy purpose.

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Daguerrotype – the first ever practically used photographic technique Daguerrotype – the first ever practically used photographic technique

Abstract

The study summarises the basic information on daguerreotype, the first ever practically used photographic process, which was used mainly in the period 1840 - 1860. Daguerrotype takes advantage of a photosensitive layer of silver halides on a silver layer to capture an image, it uses a reaction of silver with mercury vapours to develop the image. The production process via daguerreotype as described hasn’t changed since its deployment and stabilisation in the middle of 19th century. The properties of a daguerreotype image are given by its soft microstructure, which could have only been described after introduction of the electron microscopy. The susceptibility of daguerrotypes to damage and degradations stems not only from their low mechanical resistance but also from unsuitable conservation interventions and archiving conditions.

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Novel lignocellulosic wastes for comparative adsorption of Cr(VI): equilibrium kinetics and thermodynamic studies

Abstract

Cr(VI) adsorption was studied for abundantly available low-cost lignocellulosic adsorbents in Pakistan namely, tobacco stalks (TS), white cedar stem (WCS) and eucalyptus bark (EB). Several process variables like contact time, adsorbent dose, pH, metal concentration, particle size and temperature were optimized in batch mode. EB showed high Cr(VI) adsorption of 63.66% followed by WCS 62% and TS 57% at pH 2, which is higher than most of the reported literature. Langmuir isotherm (R2 = 0.999) was well fitted into the equilibrium Cr(VI) data of EB, suggesting homogeneous active sites and monolayer coverage of Cr(VI) onto the EB surface. Freundlich (R2 = 0.9982) isotherm was better fitted to the equilibrium data of TS and WCS, revealing the adsorption sites with heterogeneous energy distribution and multilayer Cr(VI) adsorption. Moreover, the Cr(VI) adsorption of studied adsorbents followed the pseudo-second order kinetic model. Thermodynamic properties were investigated in two temperature ranges, i.e., T1 (303–313 K) and T2 (313–323 K). TS and EB showed the exothermic at T1 and endothermic reactions at T2 with entropy controlled adsorption at the solid-liquid interface, and WCS exhibited an opposite thermal trend with decreasing disorderness at solid-liquid interface as temperature rises. Gibbs free energy (ΔG>0) confirmed the non-spontaneous adsorption process for all studied adsorbents.

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Silver nanoparticles deposited on calcium hydrogenphosphate – silver phosphate matrix; biological activity of the composite

Abstract

The composite containing nanosilver uniformly deposited on matrix composed of CaHPO4 x 2H2O (brushite, ca 89 mass %), CaHPO4 (monteonite, ca 9.5 mass%), and Ag3PO4 (0.5 mas%) was obtained by addition of calcium nitrate and silver nitrate aqueous solution at 30:1 Ca:Ag molar ratio into excess of (NH4)2PO4 solution at pH 5.0 – 5.5. The isolated solid was characterized by STEM, XRD, and LDI mass spectrometry. It has been found that nanosilver was uniformly distributed within composite as <10 nm diameter sized nanoparticles. Determination of silver by AAS showed that 60% of silver is present as Ag(0) nanoparticles, the present as matrix Ag3PO4 as identified by XRD method. The composite showed strong growth inhibition in E. coli and P. aeruginosa strains, and moderate towards S. aureus. The C. albicans cells were the most resistant to the tested material, although still composite was moderately cytostatic for the yeast.

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Characterization and components separation of corn stover by alkali and hydrogen peroxide treatments

ned Kraft Pulp. Holzforschung 54(6), 618-624. DOI:10.1515/HF.2000 .104. 16. Xiao, B., Sun, X.F. & Run, R.C. (2001). Chemical, structural, and thermal charactcrizations of alkali-soluble ligins and hemicelluloses and cellulose from maize stems, ryc straw, and rice straw, Polym. Degrad. Stab. 74(2), 307-319. DOI: 10.1016/ S0141-3910(01)00163-X. 17. Sain, M. & Panthapulakkal, S. (2006). Bioprocess preparation of wheat straw fi bers and their characterization , Ind Crop Prod. 23(1), 1-8. DOI: 10.1016/j.indcrop.2005

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Thin-layer drying of sawdust mixture

drying time and product quality. Bioresources 8(1), 855–863. DOI: 10.15376/biores.8.1.855-863. 6. Dincer, I. (1998). Moisture transfer analysis during drying of slab woods. Heat Mass Trans. 34(4), 317–320. DOI: 10.1007/s002310050265. 7. Gigler, J.K., van Loon, W.K.P., van den Berg, J.V., Sonneveld, C. & Meerdink, G. (2000). Natural wind drying of willow stems. Biomass Bioenerg 19(3), 153–163. DOI: 10.1016/S0961-9534(00)00029-5. 8. Weres, J., Olek, W. & Guzenda, R. (2000). Identification of mathematical model coefficients in the analysis of the

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Possibilities of utilizing the solid by-products of biodiesel production - a review

.02.002. Nielsen, C. (1995). Utilisation of straw and similar agricultural residues. Biomass and Bioenergy , 9(1-5), 315-323, DOI:10.1016/0961-9534(95)00099-2. Paukszta, D. (2006). Chemical composition of the lignified part of the rape straw stem. Zeszyty Instytutu Hodowli i Aklimatyzacji Roślin w Radzikowie , Zeszyt 1, 143-150 (in Polish). Van de Velde, K. & Kiekens, P. (2001). Thermoplastic pultrusion of natural fibre reinforced composites. Composite Structures 54(2-3), 355-360, DOI:10.1016/S0263

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