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Maroš Sirotiak and Alica Bartošová

, M.D. (2004): Elemental compositions, FT-IR spectra and thermal behavior of sedimentary fulvic and humic acids from aquatic and terrestrial environments. Geochemical Journal , 38, p. 255–264. GLASS, D.W.; JOHNSON, D.W.; BLANK, R.R.; MILLER, W.W. (2008): Factors affecting mineral nitrogen transformation by soil heating: a laboratory – simulated fire study. Soil Science , 173, 6, p. 387–400. GONZÁLEZ-PÉREZ, J.A.; GONZÁLEZ-VILA, F.J.; ALMENDROS, G.; KNICKER, H. (2004): The effect of fire on soil organic matter – a review. Environment International 30

Open access

Beti Rogina-Car, Sandra Flincec Grgac and Drago Katovic

., Qian, G. (2009). Analysis of the chemical composition of cotton seed coat by Fourier-transform infrared (FT-IR) microspectroscopy. Cellulose, 16, 1099-1107. DOI 10.1007/s10570-009-9349-2 [16] Edwards, H. G. M., Farwell, D. W., Webster, D. (1997). FT Raman microscopy of untreated natural plant fibres. Spectrochimica Acta Part A, 53, 2383-2392.

Open access

Martin Kopani, Milan Mikula, Daniel Kosnac, Jan Gregus and Emil Pincik

), 475709. [9] M. J. Sailor and E. J. Lee, “Surface Chemistry of Luminescent Silicon Nanocrystallites”, Advanced Materials , vol. 9, no. 10 (1997), 783–793. [10] C. Q. Lai, W. Zheng, W. K. Choi and C. V. Thompson, “Metal Assisted Anodic Etching of Silicon”, Nanoscale , vol. 7 (2015), 11123–11134. [11] Z. H. Wang, T. Urisu, H. Watanabe, K. Ooi, G. R. Rao, S. Nanbu, J. Maki and M. Aoyagi, “Assignment of Surface IR Absorption Spectra Observed the Oxidation Reactions: 2H + H 2 O/Si(100) and H 2 O + H/Si(100)”, Surface Science , vol. 57, no. 5 (2005) 330

Open access

Inga Zinicovscaia, Alexey Safonov, Varvara Tregubova, Victor Ilin, Liliana Cepoi, Tatiana Chiriac, Ludmila Rudi and Marina V. Frontasyeva

Abstract

Spirulina platensis biomass is widely applied for different technological purposes. The process of lanthanum, chromium, uranium and vanadium accumulation and biosorption by Spirulina platensis biomass from single- and multi-component systems was studied. The influence of multi-component system on the spirulina biomass growth was less pronounced in comparison with the single-component ones. To trace the uptake of metals by spirulina biomass the neutron activation analysis was used. In the experiment on the accumulation the efficiency of studied metal uptake changes in the following order: La(V) > Cr(III) > U(VI) > V(V) (single-metal solutions) and Cr(III) > La(V) > V(V) > U(VI) (multi-metal system). The process of metals biosorption was studied during a two-hour experiment. The highest rate of metal adsorption for single-component systems was observed for lanthanum and chromium. While for the multi-component system the significant increase of vanadium and chromium content in biomass was observed. In biosorption experiments the rate of biosorption and the Kd value were calculated for each metal. Fourier transform infrared spectroscopy was used to identify functional groups responsible for metal binding. The results of the present work show that spirulina biomass can be implemented as a low-cost sorbent for metal removal from industrial wastewater.

Open access

A. Bobrowski, A. Kmita, M. Starowicz, B. Hutera and B. Stypuła

Abstract

An attempt has been made to determine the effect of an addition of colloidal suspensions of the nanoparticles of magnesium oxide on the structure of water glass, which is a binder for moulding and core sands. Nanoparticles of magnesium oxide MgO in propanol and ethanol were introduced in the same mass content (5wt.%) and structural changes were determined by measurement of the FT-IR absorption spectra.

Open access

B. Grabowska, K. Kaczmarska, A. Bobrowski, Ż. Kurleto-Kozioł and Ł. Szymański

Abstract

The spectroscopic FT-IR and FT-Raman methods allowed to identify the cross-linking process of the aqueous composition of poly(acrylic acid)/sodium salt of carboxymethyl starch (PAA/CMS-Na) applied as a binder for moulding sands (as a novel group binders BioCo). The cross-linking was performed by physical agent, applying the UV-radiation. The results of structural studies (IR, Raman) confirm the overlapping of the process of cross-linking polymer composition PAA/CMS-Na in UV radiation. Taking into account the ingredients and structure of the polymeric composition can also refer to a curing process in a binder - mineral matrix mixture. In the system of binder-mineral matrix under the influence of ultraviolet radiation is also observed effect of binding. However, the bonding process does not occur in the entire volume of the investigated system, but only on the surface, which gives some possibilities for application in the use of UV curing surface of cores, and also to cure sand moulds in 3D printing technology.

Open access

B. Grabowska, K. Kaczmarska and A. Bobrowskia

Abstract

In this paper the results of studies of polymeric binders on the example of the new BioCo2 binder, including the problem of its renewability, are presented. The results of structural studies (FT-IR) for the BioCo2 binder before and after crosslinking, and bending strength tests Rg u fresh and renewed cured molding sands with BioCo2 binder are discussed. The cross-linking binder and curring of moulding sand was carried out by physical agents (microwave radiation, temperature). On the basis of obtained results was shown that it is possible to restore the initial properties of the adhesive of BioCo2 binder. The initial properties of moulding sand can be achieved, after the cross-linking binders and after curing in the moulding sands with bioCo2 binder , by supplementing the moulding sand composition by the appropriate amount of water.

Open access

Xin Gao, Keli Chen, Heng Zhang and Lincai Peng

Abstract

The parenchyma cellulose isolated from bagasse pith was used as an alternative resource for preparation of water-soluble cellouronic acid sodium salt (CAS). The influence of ultrasound treatment on the cellulose was investigated for obtaining CAS by regioselective oxidization using 4-acetamide-TEMPO and NaClO with NaClO2 as a primary oxidant in an aqueous buffer at pH 6.0. The yield, carboxylate content and polymerization degree (DP) of CAS were measured as a function of ultrasonic power, agitating time and cellulose consistency by an orthogonal test. The ultrasound-treated conditions were further improved by discussion of ultrasonic power, the most important factor influencing the yield and DP. An optimized CAS yield of 72.9% with DP value (DPv) of 212 was found when the ultrasonic strength is 550 W, agitating time is 3 h and cellulose consistency is 2.0%. The oxidation reactivity of cellulose was improved by ultrasonic irradiation, whereas no significant changes in crystallinity of cellulose were measured after ultrasonic treatment. Moreover, the ultrasound treatment has a greater effect on yielding CAS from parenchyma cellulose than from bagasse fibrous' one. The CAS was further characterized by Fourier transform infrared spectroscopy (FT-IR) and Scanning electron microscopy (SEM).

Open access

K. Kaczmarska, A. Bobrowski, S. Żymankowska-Kumon and B. Grabowska

properties of modified starch binder for foundry. Journal of Materials Processing Technology. 183(2-3), 407-411. DOI:10.1016/j.jmatprotec.2006.11.001. [4] Grabowska, B., Sitarz, M., Olejnik, E., Kaczmarska, K. & Tyliszczak, B. (2015). FT-IR and FT-Raman studies of cross-linking processes with Ca2+ ions, glutaraldehyde and microwave radiation for polymer composition of poly(acrylic acid)/sodium salt of carboxymethyl starch - In moulding sands, Part I. Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy. 135, 529-535. DOI: 10.1016/j.saa.2015

Open access

D. Nowak

., Kaczmarska, K. & Tyliszczak, B. (2015). FT-IR and FT-Raman studies of cross-linking processes with Ca2+ ions, glutaraldehyde and microwave radiation for polymer composition of poly(acrylic acid)/sodium salt of carboxymethyl starch - In moulding sands, Part II. Spectrochim. Acta Part A Mol. Biomol. Spectrosc. 151, 27-33. DOI: 10.1016/j.saa.2015.06.084. [13] Stachowicz, M., Opyd, B. & Granat, K. (2015). Comprehensive assessment of polymeric materials for foundry tooling used in microwave field. Arch. Metall. Mater. 60(1), 335-339. DOI: 10.1515/amm-2015