Metals in organic and conventional wheat flours determined by an optimised and validated ICP‐MS method

This study was undertaken (i) to optimise and validate a suitable method for multi‐element determination in cereal products and (ii) to evaluate multi‐element content differences in commercially available conventional vs. organic wheat flours. Presented ICP‐MS method is simple and accurate for the determination of eighteen elements in cereal food. Obtained results show differences in metal content between conventional and organic wheat flours and confirm that both types of production are well within the toxicological safety limits regarding the metal contents. The significant differences among conventional vs. organic wheat flours were obtained for As, Cd, Cr, Fe, Mg, Mo, Ni and V. Toxic metals (Al, As, Cd and Pb) input was higher in conventional compared with organic wheat flours. However, further and long‐term research is needed to clearly underline the effects of organic agricultural practice on the quality of food products.     

Synthesis and characterization of Cu-doped polymeric carbon nitride

Polymeric carbon nitride doped with copper through a solid-state reaction was characterized by several techniques, among them are UV-visible spectroscopy, infrared spectroscopy, X-ray photoelectron spectroscopy, etc. The material is a semiconductor with a wide band gap of 2.74 eV. Sites of both Cu(I) and Cu(II) were detected, apparently only coordinated by the polymer. The material comprises crumpled nanosheets, and is substantially an amorphous layered material with a prevalent 2D structure with low inter-planar interactions, as shown by X-ray diffractometry and TeraHertz spectroscopy. Photo-oxidation of benzyl alcohol was used to probe the active sites of the material, comparing them with the non-doped material. The higher activity and selectivity toward salicylic alcohol of the non-doped material can be due to both a more localized electron transfer and a longer lifetime of the hole–electron pair. Cu-CN favored the oxidation of hydroxymethyl group. Therefore, the presence of copper can favor different reaction pathways with respect to the non-doped material.     

Soft Matter Technology at KIT: Chemical Perspective from Nanoarchitectures to Microstructures

Bioinspiration has emerged as an important design principle in the rapidly growing field of materials science and especially its subarea, soft matter science. For example, biological cells form hierarchically organized tissues that not only are optimized and designed for durability, but also have to adapt to their external environment, undergo self‐repair, and perform many highly complex functions. Being able to create artificial soft materials that mimic those highly complex functions will enable future materials applications. Herein, soft matter technologies that are used to realize bioinspired material structures are described, and potential pathways to integrate these into a comprehensive soft matter research environment are addressed. Solutions become available because soft matter technologies are benefitting from the synergies between organic synthesis, polymer chemistry, and materials science.     

Non‐destructive detection of corrosion applied to steel and galvanized steel coated with organic paints by the pulsed phase thermography

Organic coatings in the automobile industry have to resist corrosion and mechanical damage from stone chipping. Currently, no tool is established in industrial non‐destructive applications for analyzing the damage of stone‐impacts and the following corrosion after accelerated corrosion tests. Measurement methods such as the scanning Kelvin probe can analyze the corrosion progress in a detailed manner, but with a long measurement time. The pulsed phase thermography (PPT) is a non‐destructive tool to analyze inhomogeneities and defects in materials, with a huge field of applications existing. The present work shows advances in using the PPT to detect propagation of corrosion under coatings. Physical principles of the mechanism of the corrosion detection under coatings are described. Results of measurements of organic coatings on carbon steel as well as of organic coated galvanized steel show the corrosion propagation. Influencing factors to the measurement such as the thickness of the coatings are investigated, but no significant effect on the quality of the analysis was found. The corrosion progress can be monitored by the PPT fast and reliably. The achieved results correlate with the theoretical basis and the test results after surface characterization and destructive analysis of samples.     

Continuous Cloud Point Extraction of Volatile Organic Contaminants from Wastewater in a Multi-Stage Rotating Disc Contactor: Effect of Structure and Concentration of Solutes

Abstract

Cloud point extraction (CPE) has been successfully scaled up to continuously remove aromatic contaminants from wastewater in a multi-stage rotating disc contactor (RDC) using t-octylphenolpolyethoxylate. The extraction performances for the removal of organic solutes with different structures and degrees of hydrophobicity were compared here for both batch and continuous CPE. Included are the volatile aromatics benzene, toluene, and ethylbenzene; volatile chlorinated compounds dichloroethane, trichloroethylene, and tetrachloroethylene; and non-volatile phenolics phenol, o-cresol, and catechol. The higher the K_ow (octanol-water partition coefficient) or hydrophobicity of the solutes, the better the extraction due to the greater affinity of solutes to solubilize into micelles. The empirical linear correlations between log K_ow, log (solute partition ratio), and log (height of transfer unit or HTU) were developed. Toluene is used as a model solute for the study of effect of initial solute concentrations in the continuous RDC. The extraction ability decreases as the concentration of toluene in the wastewater increases mainly due to coacervate entrainment into the overhead effluent.     

Experimental study of the natural organic matters effect on the power generation of reverse electrodialysis

In this paper, the effect of natural organic matters (NOMs), which are typically present in river and seawater, on the power generation of reverse electrodialysis was studied. Bovine serum albumin, humic acid, and sodium alginate were used as models of NOMs. A NOM model was added to concentrated salt water, diluted salt water, and/or both of them. Power density was used to measure the resulted power generation. Fourier transform infrared spectroscopy and scanning electron microscope were used to characterize the presence of NOMs on the membrane surfaces. The effect of NOMs on the generated power density was clearly observed. This effect was influenced by the NOM's type, the NOMs concentration, and the compartment in which NOMs are added. Fourier transform infrared spectroscopy and scanning electron microscope data confirmed that NOMs are deposited on both anion and cation exchange membrane surfaces. While all NOMs added to concentrated salt water did not influence the generated power density, different power density behavior was resulted from the different NOMs added to diluted salt water, where NOMs could increase or decrease or remain the generated power density. Thus, besides NOM's type, the salt concentration is very critical to determine the effect of NOMs on the generated power density. Copyright © 2017 John Wiley & Sons, Ltd.     

Reversible adsorption of metalworking fluids (MWFs) on Cu-BTC metal organic framework

Metalworking fluids(MWFs) are classified as hazardous substances. Due to the characteristics of the stable oil–water emulsions, it requires more costly and complicate treatment techniques to remove oil from spent MWFs. Metal organic frameworks(MOFs) are a porous network material used to remove contaminants from environment. One of the most prominent of MOFs is HKUST-1 or Cu-BTC. In this study, the Cu-BTCs were prepared by solvothermal method in various conditions and used as absorbent for removing oil micelles in MWF emulsion. The particle size of all synthesized Cu-BTCs ranged from ≈80 to 400 nm. The ability of all synthesized Cu-BTCs to remove oil micelle was greater than 95% in 60 min, while the capacity of GAC was obtained the result for only 6.8%. The maximum adsorption capacity(q _(max)) of oil micelles on Cu-BTCs was 1666.7 mg·g~(-1). The highest removal capacity of oil micelles in MWF emulsion is greater than 99% in 24 h by using Cu-BTCs washed with either butanol or ethanol.