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Copyright of Journal of Central European Agriculture is the property of Journal of Central European Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The study aimed to evaluate the humus quality of anthropogenic soils derived from flysch deposits. A total of 10 samples were collected in the top-soil horizon (0-20 cm) of olive groves in Kaštela Bay in Middle Dalmatia, Croatia. Five samples were taken from traditional low-input olive groves (TOG), and the other five samples were from intensive ones (IOG). The soil samples were analysed for basic soil properties: particle size distribution, pH, carbonate content, P2O5, K2O, and soil organic carbon (SOC) content. Humic substance isolation was done following the procedure given by Schnitzer (1982). Spectroscopic characterization of humic substances was carried out by measuring absorbances in VIS spectral range (400-700 nm). Optical index E4/E6 (ratio of optical absorbance at 465 and 665 nm for humic substances in solution) was calculated. The mean value of SOC content in soils of TOG was lower than in soils under IOG (1.20 and 1.60%, respectively). The absorption spectrum of the studied soils showed a monotonous decrease of absorbance from 400 to 700 nm. The E4/E6 indices for soils under TOG varied from 4.60 to 5.00, while for soils under IOG were in the range of 4.83 - 6.89. The E4/E6 indices > 4 revealed low humus quality in studied soils. However, soils under TOG have lower mean values E4/E6 index in comparison to soils under IOG (4.76 and 5.70, respectively), indicating slightly higher humus quality. [ABSTRACT FROM AUTHOR]

The collection Manuscripta Americana in Berlin consists of fragmented codices acquired by Alexander von Humboldt in Mexico. Some of these Humboldt Codices are published as hieroglyphic writings of the Aztecs in "Vues des Cordilleres et Monuments des Peuples indigènes de l'Amerique". Starting from a special compilation of seven fragments on plate 36 in the "Atlas", we investigated the corresponding original fragments using material analysis in order to clarify their historical relations. The analyses were carried out with X-ray fluorescence analysis, VIS spectroscopy, and infrared spectroscopy in diffuse reflection and revealed typical indigenous colors like cochineal, indigo, and organic yellows (e.g. mangrove and zacatlaxcalli). Four fragments under investigation show exactly the same material and thus must once have belonged together in one compendium. An additional manuscript from Mizquiahuala also shown on plate 36 can be matched to another one that is not published in the "Atlas". [ABSTRACT FROM AUTHOR]

Herein, the proof of concept of a sodium polysulfide battery consisting of two electrode chambers being separated by a solid electrolyte is described. The concept is suited for dissolved polysulfide cathodes and has the advantage that both half reactions can be optimized separately. The formation of solid sulfide discharge products is identified as the major limiting factor for cell cycling. This issue can be alleviated by adding solid P2S5. Further improvement can be achieved by replacing diglyme (2G) as the cathode compartment solvent with tetramethylurea (TMU). Using TMU, the cell cycles with Coulombic efficiencies >99% and capacities of 800 mAh g−1 are maintained for at least 30 cycles. Viscosity, density, conductivity, and the electrochemical stability window values of the 2G‐ and TMU‐based electrolytes are compared. The latter shows higher viscosity (2.806 vs 1.603 mPa s), higher density (1.016 vs 0.996 g cc−1), and higher conductivity (4.27 vs 1.45 mS cm−1). The oxidative stability limit of the TMU electrolyte is 3.2 V versus Na+/Na, which is sufficient for polysulfide redox reactions. Vis spectroscopy is used to follow the electrode reaction. In case of TMU, the reaction is based on the redox activity of S3−• radicals (blue coloration of the catholyte solution). [ABSTRACT FROM AUTHOR]

The collection Manuscripta Americana in Berlin consists of fragmented codices acquired by Alexander von Humboldt in Mexico. Some of these Humboldt Codices are published as hieroglyphic writings of the Aztecs in "Vues des Cordilleres et Monuments des Peuples indigènes de l'Amerique". Starting from a special compilation of seven fragments on plate 36 in the "Atlas", we investigated the corresponding original fragments using material analysis in order to clarify their historical relations. The analyses were carried out with X-ray fluorescence analysis, VIS spectroscopy, and infrared spectroscopy in diffuse reflection and revealed typical indigenous colors like cochineal, indigo, and organic yellows (e.g. mangrove and zacatlaxcalli). Four fragments under investigation show exactly the same material and thus must once have belonged together in one compendium. An additional manuscript from Mizquiahuala also shown on plate 36 can be matched to another one that is not published in the "Atlas". [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles have received great interest for their use in cancer diagnostics and therapy. They can be loaded with the chemotherapeutic agents and used for the targeted delivery to the tumor and the retention of the drugs there under the external magnetic field. In the present paper, we investigated the interaction between magnetic Fe3O4 nanoparticles, both bare and coated with trisodium citrate, and anticancer drug doxorubicin in the base and acidic forms, respectively. The changes in the drug absorption spectra in the visible region and the shift of ferromagnetic resonance spectra taking place at the drug-nanoparticle interaction were analyzed. The spectrophotometric titration data were processed using the Langmuir model of equilibrium binding. For both systems, we report the calculated thermodynamic binding parameters including the drug-nanoparticle binding constants and binding site sizes. We show that in order to interact with the doxorubicin molecules in acidic form, the surface of the nanoparticles needs to be modified with trisodium citrate which provides their surface with the negative charge. At the same time, the bare magnetite nanoparticles are able to interact with the base form of the drug. The comparison of the binding parameters in both systems has shown that the nanoparticle-citrate-doxorubicin system is more promising in terms of biomedical application. [ABSTRACT FROM AUTHOR]

Fe doped SnO2 transparent thin film nanostructures were grown by chemical solution deposition and its electric field induced resistive switching properties were investigated for non-volatile resistive random access memory (RRAM) applications. Simple, low temperature solution process growth of SnO2:Fe thin film nanostructures was employed. Grazing incidence X-ray diffraction (GIXRD) and atomic force microscopy (AFM), respectively, confirmed a phase pure cubic growth with mono-disperse nanocrystallites of ~ 20 nm. Sharp interface with substrate and top metal electrodes were achieved. Reproducible hysteresis in the I-V curves with symmetrical resistance switching ratio of more than 4 x 103 at a low operating voltage of ± 1.1 V has been demonstrated. Large values of memory retention of about 5 moths; confirmed the nonvolatile behaviour of the device cell consisting of Ag/SnO2:Fe/Ag planar structure. A mechanism involving the space charge limited current combined with Schottky conduction at the metal/oxide interface is proposed. A possible mechanism of the formation and rupture of conducting filament is proposed based on the Joule heating effect with external electron injection at the Ag/SnO2 interface. [ABSTRACT FROM AUTHOR]

A novel cell for complex spectroelectrochemical and nanomorphological characterization of phthalocyanine has been developed. The applicability and universality of the cell allows performing both in-situ and ex-situ characterization of the same sample, in solid and solution state, respectively, which was demonstrated on tetramethyltetra-3,4-pyridine-porphyrazino cobalt as water soluble and tetraneopentoxyphthalocyanine cobalt as water insoluble phthalocyanine based compound. The cell is composed of a planar freely replaceable bottom formed by a basal plane of highly ordered pyrolytic graphite. It allows complete characterization of modified electrode on same electrode, from spectral observation of modification process via atomic force microscopy to spectroelectrochemical characterization of redox and catalytic behavior. The relatively inert HOPG electrode serves as a substrate for phthalocyanine compounds and also as a backscattering mirror for in-situ reflection spectroscopy. This makes the cell suitable for spectroelectrochemical studies of phthalocyanine both as HOPG-supported thin film and in the solution. Moreover, the cell can take the advantage of optional utilization of supported thin layer interface of two immiscible electrolyte solutions allowing spectroelectrochemical analysis of sub-microgram quantities of water insoluble compounds. Graphical abstract: . [ABSTRACT FROM AUTHOR]

The aim of the article is to investigate the potential of honey discrimination (on the base of its botanical origins) by Vis spectroscopy and chemometric analysis. Fifty-five samples from three types of honey (acacia, linden, and honeydew) are measured by a spectrophotometer "Helios Omega" with recorded wavelength range of 380~780 nm for calibration of honey classifier. Firstly, principal components analysis (PCA) is used for reducing the number of inputs and for a proper visualization of the experimental results. Next, the first two principal components (PCs) are combined separately with k-means clustering (KMC), Naïve Bayes classification (NBC), and linear and quadratic discriminant analysis (LDA, QDA) to develop PC-KMC, PC-NBC, PC-LDA and PC-QDA models, respectively. The comparative analysis of the four classifiers is based on leave-one-out-cross validation test carried out in MATLAB environment. [ABSTRACT FROM AUTHOR]

We have synthesized a series of NiII-pdto complexes - [Ni(pdto)(NO3)]NO3·H2O (C1), [Ni(pdto)(H2O)2](NO3)2 (C2), and [Ni(pdto)(NO3)(H2O)]NO3 (C3), with pdto = 1,8-bis(2- pyridyl)-3,6-dithiaoctane - with different spectroscopic responses associated with the coordination modes of the nitrato moiety. Through UV/Vis spectroscopy and electrochemical experiments it was established that in acetonitrile solution the compounds C1, C2, and C3 are each transformed into the same chemical species [Ni(pdto)NO3]+. Cyclic voltammetry experiments gave evidence of two consecutive one-electron transfers associated with NiII-(pdto) + 1 e-→NiI- (pdto) and NiI-(pdto) + 1 e-→Ni0 + pdto processes, which are in agreement with the high flexibility of the pdto ligand with regard to accommodating the preferred geometry of the central atom. The complexation reaction between pdto and the starting salt Ni(NO)3·6H2O in acetonitrile was also studied by UV/Vis spectroscopy and cyclic voltammetry. A linear relationship between the experimentally determined value of 10 Dq and the Δ(EHOMO-LUMO) energy values obtained by computational methods was found. [ABSTRACT FROM AUTHOR]

In this study, ethylene vinyl acetate-fly ash (EVA-FA) composites were prepared by the melt mixing technique using a rheomixer for the purpose of removing 2,4,6-trichlorophenol (TCP) and p-nitrophenol (PNP) from water. The fly ash was characterized by X-ray fluorescence spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD); the composites were characterized using SEM and XRD. Brunauer, Emmett, and Teller (BET) measurements revealed a surface area ( SBET) of 0.07110 m2/g for the fly ash. The adsorption of TCP and PNP were monitored by UV-Vis spectrophotometer. The maximum adsorption of PNP was obtained at pH 5 after a contact period of 12 h, whereas that of the TCP was obtained at pH 4 after a period of 10 h has elapsed. The equilibrium adsorption data were evaluated using Langmuir and Freundlich adsorption isotherm models. The Langmuir adsorption model gave the better correlation coefficients for the equilibrium adsorption data. The kinetics data followed the pseudo-second-order model for both TCP and PNP. The theoretical maximum adsorption capacity ( qmax) of the adsorbent used in the study was found to be 3.424 mg/g and 2.544 mg/g for TCP and PNP, respectively. The desorption of the phenols from the composites was performed using 0.2 M NaOH. About 82.6% and 76.3% of TCP and PNP were recovered, respectively. The study showed that the pH of the solution and contact time play a significant role in the adsorption process. Furthermore, we have demonstrated that EVA-FA composites have the potential to adsorb phenols from acidic water solutions. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

Solution equilibrium studies on Cu-L-L ternary systems have been performed by pH-potentiometry, UV-Vis spectrophotometry and EPR methods {where L corresponds to a polyamine such as ethylenediamine (en), diethylenetriamine (dien), N, N, N′, N′, N″-pentamethyldiethylenetriamine (Medien)} and L denotes 2-aminoethylphosphonic acid (β-alaninephosphonic acid)}. The results suggest the formation of heteroligand complexes with [Cu(L)(β-Ala(P))] stoichiometry in all of the studied systems. Additionally, in the system with en, [Cu(en)(β-Ala(P))H] is formed in basic solutions. Our spectroscopic results indicate tetragonal geometry for the [Cu(en)(β-Ala(P))] species, a geometry slightly deviated from square pyramidal for the [Cu(dien)(β-Ala(P))] complex, and somewhat stronger geometry distortion was present for the [Cu(Medien)(β-Ala(P))] complex. The coordination modes in these heteroligand complexes are discussed. [ABSTRACT FROM AUTHOR]

Microspectrometry in the visible range is routinely applied in comparative examination of criminalistic traces such as paint chips, single fibers, and inks on questioned documents. It makes it possible to analyze a very small amount of sample and provides objective information about its color as well as helping to distinguish samples of similar colors. Measurements of Vis spectra are performed both in transmittance and reflectance mode, depending on the kind of traces. Application of the CIELab color system enables us to define color precisely and make use of color databases. [ABSTRACT FROM AUTHOR]

Solution equilibrium studies on Cu-L-L ternary systems have been performed by pH-potentiometry, UV-Vis spectrophotometry and EPR methods (L corresponds to polyamines such as ethylenediamine (en), diethylenetriamine (dien), or N, N, N′, N′, N″-pentamethyldiethylenetriamine (Medien) and L represents 1-aminoethylphosphonic acid ( α-alaninephosphonic acid)). The obtained results suggest the formation of heteroligand complexes with [Cu(L)( α-Ala(P))] stoichiometry in all studied systems. Additionally, in the system with en the [Cu(en)( α-Ala(P))H] species is formed in basic solution. Our spectroscopic results indicate tetragonal geometry for the [Cu(en)( α-Ala(P))] species, geometry slightly deviated from square pyramidal for the [Cu(dien)( α-Ala(P))] complex and strongly deviated from square pyramidal towards trigonal bipyramidal for the [Cu(Medien)( α-Ala(P))] species. The coordination modes in these heteroligand complexes are discussed. [ABSTRACT FROM AUTHOR]

Solution equilibrium studies on the Cu(II)-polyamine-(aminomethyl)phosphonic acid (glycinephosphonic acid) ternary systems (polyamine: ethylenediamine (en), diethylenetriamine (dien), N, N, N′, N′, N″-pentamethyldiethylenetriamine (Me5dien)) have been performed by pH-potentiometry, UV–vis spectrophotometry and EPR methods. The obtained results suggest the formation of the heteroligand complexes with [Cu(A)(Gly(P))] stoichiometry in all studied systems. Additionally, in the systems with dien the protonated [Cu(dien)(H–Gly(P))]+ species also exists in acid solution and in the system with en the [Cu(en)(Gly(P))H-1]− species is formed in the basic solution. Our spectroscopic results indicate the tetragonal geometry for the [Cu(en)(Gly(P))] species, the geometry slightly deviated from square pyramidal for the [Cu(dien)(Gly(P))] complex and strongly deviated from square pyramidal towards trigonal bipyramidal for the [Cu(Me5dien)(Gly(P))] species. The coordination modes in these heteroligand complexes are discussed. [ABSTRACT FROM AUTHOR]

The addition of different ionenes, polycations with defined structure and charge distances, to methylorange 1 in very dilute solutions of water resulted in an observable shift of the absorption maxima from 464 nm to shorter wavelengths. The extent of this so-called metachromasy effect was found to be dependent on the nature of the hydrophobic unit of the polymer backbone. The comparison of UV/VIS spectra's of these solutions with the absorption of a film of a model substance - a dication with methylorange as counteranion - lead to the conclusion that ionenes undergo an exchange of the counteranions when added to a dilute solution of methylorange. Precipitation is slowed down, but the absorption is equivalent with solid product. The new absorption spectra of methylorange can be explained by the interaction of the quaternary nitrogen with the dye anion. [ABSTRACT FROM AUTHOR]