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Marcin Kuśmierz and Sylwia Pasieczna-Patkowska

Abstract

The interaction of EDTA disodium salt with zinc oxide was investigated by photoacoustic (PA) FT-IR. It was demonstrated that EDTA-III adsorbs on ZnO, and the process mimics behaviour of EDTA-oxide systems, in which IEPS of oxide catalytic supports is higher than 9. Model of the interaction, described in literature, was discussed.

Open access

Selvakumar Dineshkumar, Ganesamoorthi Thirunarayanan, Perumal Mayavel and Inbasekaran Muthuvel

Abstract

Zeolite Y clay modified copper nitrate catalyst was prepared. The obtained catalyst was analyzed by SEM, EDS, and powder XRD techniques. The zeolite Y clay modified copper nitrate catalyst was used for the synthesis of various substituted mesalazine by sulfonylation. The synthesized sulfonamides have been characterized by GC-MS, IR, 1H, 13C and HSQC NMR techniques. The yield percentages of sulfonamides are more than 85%.

Open access

Ioana A. Gorodea

6 and Ca2MnWO6: a neutron diffraction study. J. Phys. Condens. Mat. 2002, 14, 38, 8817-8830. 15. Lavat, A. E., Baran, E. J. IR-spectroscopic characterization of A2BB’O6 perovskites. Vib. Spectrosc. A. 2003, 32, 167-174. 16. Martinez-Lope, M. J., Alonso, J. A., Casais, M. T., Garcia-Hernandez, M., Pomjakushin, V. Preparation, structural study from neutron diffraction data and magnetism of the disordered perovskite Ca(Cr0.5Mo0.5)O3. J. Solid State Chem. 2006, 179 ,8, 2506-2510

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Kristīne Kalneniece, Andrejs Bērziņš, Zaiga Petriņa, Kristīne Ruģele, Elīna Salava, Kārlis Švirksts, Māra Grūbe, Vizma Nikolajeva and Olga Mutere

.06.002 [10] J. De Vrieze, L. Raport, B. Willems, S. Verbrugge, E. Volcke, E. Meers, L. T. Angenent, and N. Boon, “Inoculum selection influences the biochemical methane potential of agro-industrial substrates,” Microbial Biotechnology , vol. 8, no. 5, pp. 776–786, Mar. 2015. https://doi.org/10.1111/1751-7915.12268 [11] S. Tandy, J. R. Healey, M. A. Nason, J. C. Williamson, D. L. Jones, and S. C. Thain, “FT-IR as an alternative method for measuring chemical properties during composting,” Bioresource Technology , vol. 101, no. 14, pp. 5431–5436, Jul. 2010. https

Open access

S. Pasieczna-Patkowska and J. Ryczkowski

Spectroscopic studies of alumina supported nickel catalysts precursors: Part II - catalysts prepared from alkaline solutions

Nickel alumina supported catalysts were prepared from alkaline solutions of hexaamminenickel nitrate by CIM and DIM methods (classical and double impregnation, respectively). The catalysts exhibited different nickel species due to the existence of various metal-support interaction strengths. As a consequence, the reducibility and other surface properties changed as a function of the preparation method. The aim of this work was to study the interaction between the metal precursor and alumina surface by means of FT-IR (Fourier transform infrared) and FT-IR/PAS (FT-IR photoacoustic spectroscopy).

Open access

Zofia Rzączyńska, Anna Danczowska-Burdona and Marek Drewniak

Abstract

The lanthanide(III) complexes with 2,3-pyridinedicarboxylate ligand (PDC) were obtained as crystalline compounds from the water solutions. These compounds form the series of Ln2(PDC)3 ・ nH2O. All compounds are stable in air and insoluble in both water and common organic solvents. The hydrated complexes have been characterized by elemental analysis, thermal analysis (TG/DSC/DTA, and TG−FT-IR), FT-IR spectroscopy and X-ray analysis. 2,3-pyridinedicarboxylates of lanthanides(III) are stable in air below 313−323 K. Upon heating, hydrated complexes lose crystallization and lattice water in two steps. The values of dehydration enthalpy complexes are calculated from the DSC curves. The anhydrous compounds are stable at the temperature from 473 K to about 623 K and when heated they decompose to lanthanide oxides. Thermal and spectroscopic studies are essential for further studies and classification of compounds as MOF-like structures.

Open access

L. Chmielarz, A. Węgrzyn, A. Kowalczyk, S. Witkowski, R. Walton and A. Matusiewicz

Studies of Zn-Al-Ce mixed oxides as catalysts for diesel soot combustion

A series of Zn-Al-Ce mixed oxides was synthesized by a co-precipitation method. The obtained samples were characterized with respect to composition (XRF), structure (XRD, FT-IR) and texture (BET). Zn-Al-Ce mixed oxides were tested as catalysts of diesel soot combustion. The best catalytic activity was found for Zn2Ce oxide system, which operated in the temperature range of 350-500°C.

Open access

Marius Zaharia, Gabi Drochioiu, Gheorghiță Zbancioc and Vasile Robert Grădinaru

Abstract

The effects of 2,4-dinitrophenol (2,4-DNP) on the spectroscopic parameters (UV-Vis or FT-IR absorbance) or fluorescence emission of tryptophan and glycyl-tryptophan were studied. A quenching phenomenon of fluorescence was observed, attributed to interactions between the indole ring of the fluorophore and the aromatic ring of the quencher. The analysis of fluorescence spectra confirms that the quenching is dictated by 2,4-DNP concentration and pH. A combined mechanism of static and dynamic quenching was detected. The quenching phenomenon observed in this work could be employed to explain the mechanism of action of such compounds on large fluorescent peptides or proteins.

Open access

İbrahim Șen, Cem Burak Yildiz and Akın Azizoğlu

Abstract

The syntheses of new tetraaza macrocyclic compounds of variable ring sizes by non-template methods and their characterization with the help of elemental analysis and spectroscopic techniques (FT-IR, 1H-NMR, and 13C-NMR) have been reported in detail. The vibrational frequencies determined experimentally are compared with those obtained theoretically from density functional theory (DFT) and Hartree-Fock (HF) calculations. The comparisons between the experimental and theoretical results indicate that B3LYP level with both the 3-21G(d) and 6-31G+(d,p) basis sets is able to provide satisfactory results for predicting IR properties. The frontier molecular orbital diagrams and molecular electrostatic potential maps of title compounds have been also calculated and visualized at the B3LYP/6-31G+(d,p) level of theory.

Open access

K. Adamska, M. Woźniak and A. Voelkel

Surface modification of bioceramics by PEG grafting

Surface modification of Hydroxyapatite (HAp) and β-Tricalcium phosphate (β-TCP) powders was performed using hexamethylene diisocyanate (HMDI) as a coupling agent. Polyethylene glycol (Mw = 2000) was grafted to the surface of these ceramic materials. Different methods were used to characterize modified surfaces. Fourier transform infrared (FT-IR) and Attenuated Total Reflection Fourier Transform Infrared (FTIR/ATR) technique analyses confirmed the modification reaction on HAp and β-TCP surfaces. BET isotherm analysis showed the changes in textural properties of materials after modification. Elemental analysis was performed to confirm a presence of selected elements from modifier and coupling agent. Examination of dispersion stability of materials in different solvents show better stability for samples of β-TCP than HAp.