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Copyright of Journal of Anatolian Environmental & Animal Science is the property of Bulent Verep 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.)

In the study, changes in the mass of concrete filled with polyacrylamide/Fe3O4 nanoparticles in an amount of 1–2% of the cement mass in sea and formation water were studied. Besides, by performing IR and X-ray characterization of the prepared samples, the chemical state of the polyacrylamide (PAA) and the nanoparticles in the structure was also determined. Changes in mass of concrete samples containing PAA/Fe3O4 nanoparticles in highly mineralized seawater were shown to be highly dependent on the amount of nanoparticles compared to PAA. It revealed that at 2% PAA-Fe3O4/concrete, the ion penetration was limited and there was a lower weight gain as compared to the control concrete. IR spectroscopic analyses proved that the polymer was in a coordination band with cement and magnetite nanoparticles. X-ray diffraction studies showed a slight increase in the crystallinity of the concrete filled with up to 2% PAA/Fe3O4 magnetite nanoparticles. [ABSTRACT FROM AUTHOR]

In this work, gelatin (G)-polyacrylamide (PAAm)-based interpenetrating polymer network (IPN) hydrogels involving maleic acid (MA) was prepared using by radical polymerization. Full-IPN and semi-IPN hydrogels were synthesized by using glutaraldehyde and ethylene glycol dimethacrylate (EGDMA) as a crosslinker. The water absorbency of hydrogels was investigated, and the values increased with MA and G. The chemical structures of full-IPN and semi-IPN hydrogels were tested by Fourier Transform Infrared Spectroscopy (FTIR). Morphological test was done by using Scanning Electron Microscope/ Energy Dispersive X-ray Spectroscopy (SEM/EDX). Thermal properties were examined with Differential scanning calorimeter (DSC) analyzer and Thermogravimetric analysis (TGA). The mechanical analysis was performed with Zwick Universal Testing Machine. Thermal and mechanical stabilities of full-IPN hydrogel was higher than semi-IPN. The efficiency of adsorption parameters (contact time, initial feed concentration, and pH) on Chromium (VI) ion adsorbing property of Full-IPN hydrogel was also determined. Isotherms were explained with the Langmuir or Freundlich equations. According to the results of both isotherms, it can be said that the hydrogel surface was homogeneous, and the adsorption of Chromium (VI) occurred in a monolayer.

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology 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.)

Copyright of Düzce University Journal of Forestry / Düzce Üniversitesi Orman Fakültesi Ormancılık Dergisi is the property of Duzce University 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.)

Because of moderate stretchable properties of acrylamide (AAM), it is used as double network hydrogel with alginates (AAL). We prepared AAM-ALG hydrogels containing various amount of crosslinker (BIS) and concentration of calcium chloride (CaCl2) solution. A series of uniaxial compression loading tests were performed on five different AAM-ALG specimens. The specimens are loaded up to 20% strain and hold at the same strain level for 300 seconds. Concentration of CaCl2 solution dependency is clear; increasing molarity of CaCl2 yields an increase in the stress level. On the other hand, effect of amount of BIS is not dominant on mechanical properties. [ABSTRACT FROM AUTHOR]

Copyright of Ege Üniversitesi Ziraat Fakültesi Dergisi is the property of Ege Universitesi, Ziraat Fakultesi 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.)

Acrylamide is a monomer widely used as an intermediate in the production of organic chemicals, e.g. polyacrylamides (PAMs). Since PAMs are low cost chemicals with applications in various industries and waste- and drinking water treatment, a certain amount of non-polymerised acrylamide is expected to end up in waterways. PAMs are non-toxic but acrylamide induces neurotoxic effects in humans and genotoxic, reproductive, and carcinogenic effects in laboratory animals. In order to evaluate the effect of acrylamide on freshwater organisms, bioassays were conducted on four species: algae Desmodesmus subspicatus and Pseudokirchneriella subcapitata, duckweed Lemna minor and water flea Daphnia magna according to ISO (International Organization for Standardisation) standardised methods. This approach ensures the evaluation of acrylamide toxicity on organisms with different levels of organisation and the comparability of results, and it examines the value of using a battery of low-cost standardised bioassays in the monitoring of pollution and contamination of aquatic ecosystems. These results showed that EC50 values were lower for Desmodesmus subspicatus and Pseudokirchneriella subcapitata than for Daphnia magna and Lemna minor, which suggests an increased sensitivity of algae to acrylamide. According to the toxic unit approach, the values estimated by the Lemna minor and Daphnia magna bioassays, classify acrylamide as slightly toxic (TU=0-1; Class 1). The results obtained from algal bioassays (Desmodesmus subspicatus and Pseudokirchneriella subcapitata) revealed the toxic effect of acrylamide (TU=1-10; Class 2) on these organisms. [ABSTRACT FROM AUTHOR]