ElectroHeat (Sweden)

To help address global warming, various power generation methods that do not release carbon dioxide have been established, including electrostatic power generation. A wide variety of electrostatic generators have been proposed for many centuries; however, the vibration-type electrostatic generator is currently the most commonly utilised. Electricity is generated via the movement of a charge carrier, which is charged by electrostatic induction in opposition to an injection electret (Hereafter, this will be abbreviated as IE.). The carrier is displaced from the electret using external energy forms such as waves, and the resultantly generated charge is allowed to flow. As IE and charge carrier are charged with opposite polarities, a strong Coulomb force is generated between them, which acts as a braking force against the movement of the carrier. Therefore this paper present an improved method that revealed this braking force can be eliminated by placing a counter-electret (Hereafter, this will be abbreviated as CE.)—charged with the opposite polarity—adjacent to IE.

Biogenic amines (BA) are biomolecules of low molecular weight with organic basic functionalities (amine group) that are formed by the microbial decarboxylation of amino acids of fermented food/beverages. Hence BAs are an important indicator in estimating the freshness and quality of meat, seafood, and industrial food products with high protein content. The reaction of BAs with nitrites available in certain meat products forms nitrosoamine, a carcinogenic compound. Hence BAs are in general considered to be a food hazard and monitoring the level of BAs in food samples becomes crucial as their high concentrations may lead to health problems. This review offers an overview of the available chemical and electrochemical methods that are typically used for the sensing of BAs in food samples. Certain compounds are known to selectively interact with BAs via chemical or non-covalent interactions and these interactions are often accompanied by fluorescence or visible color changes (sometimes visual detection) that could be monitored/assessed using a fluorescence spectrophotometer or UV-vis spectrophotometer (colorimetric methods). The colorimetric methods are limited by sensitivity and selectivity as they are based on straight-forward chemical reactions. In the case of electrochemical sensing of BAs, mediators are often used which undergo oxidation/reduction to produce intermediates that could interact with BAs accompanied by changes in their electrochemical potential. Overall, this review summarizes the available chemical and electrochemical strategies towards the sensing of BAs with a discussion on further prospects.

Protection of steel by sacrificial coatings is of primary importance in the industry, to extend the lifetime of steel structure parts. This is frequently obtained by zinc coatings, after galvanization or electrodeposition, but pure zinc is sometimes not resistant enough when high protective properties are required. Indeed, zinc corrosion rate is quite important, even if corrosion products play an important role in protection. Therefore, Zn alloys deposition is a privileged process. However, the metallic alloy elements used for codeposition are frequently composed of harmful substances, which use is more and more regulated. In a global strategy of employees and environment protection, and to anticipate more drastic restriction, the European plating shop leader Electropoli proposed a partnership to the research institute UTINAM. The project Zincadher intended to propose an alternative to zinc alloys plating by a zinc matrix, reinforced by silica and PMMA particles which main function is to increase corrosion resistance and adhesion. To overcome the lack of availability of PMMA (poly (methyl methacrylate)) nanoparticles at a reasonable price, an original synthesis of the PMMA particles was first developed [1]. It involves the use of a custom-made ultrasonic system, were MMA (methyl methacrylate) and water mixtures are exposed to different ultrasonic systems and successive sonication steps as follows: 20 kHz → 580 kHz → 858 kHz → 1138 kHz. Then, polymerization of the droplets is conducted, in order to obtain the largest possible concentration of PMMA particles of sub micrometer size range of different electrokinetic properties [2]. In a second part of the study, electrochemical study of acid zinc electrolyte with PMMA and/or silica particle have been carried out. As ultrasound is known to improve greatly mass transfer and coating characteristics as well as particles dispersion [3], a calibration of acoustic streaming at the surface of the working electrode is conducted, to be able to compare with classical mechanical stirring with the concept of equivalent velocity. Then, after particles dispersion in an acid zinc bath, composite coatings are elaborated. The plating parameters (current density, particles nature, hydrodynamic source…) on the morphology and composition of the coatings are evaluated by SEM/EDS and XRD characterization. Acknowledgement: The authors would like to thank Electropoli Group for funding this project and the ANRT for the CIFRE convention. [1] K. Nakabayashi, T. Fuchigami, M. Atobe, Electrochimica Acta. 110 593–598 (2013) [2] L Baissac, CC Buron, L Hallez, P Berçot, JY Hihn, L Chantegrel, G Gosse Ultrasonics sonochemistry 40, 183-192 (2018) [3] JY Hihn, F Touyeras, ML Doche, C Costa, BG Pollet in Power Ultrasound in Electrochemistry: From Versatile Laboratory Tool to Engineering Solution, John Wiley & Sons, Ltd, 169-214 (2012) Figure 1

A novel hydrogen power configuration of a Light Hybrid Electric (LHE) rail train able to operate along sub-urban non-electrified rail lines is proposed and analysed in the paper. The electric motors of the emission-free LHE rail train are fed by a hybrid power unit consisting of hydrogen fuel cell stacks and a set of high-speed kinetic energy storage systems. A control strategy of the power-train components has been developed to manage power flows in order to reduce the fuel consumption. This advanced and environment friendly hybrid propulsion system offers the opportunity to increase the power-train efficiency so that the fuel consumption is minimised. Simulator software of the proposed HLE rail train has been implemented in order to design the power-train components and compute train performance. A rail transport service is considered and a round trip journey of the LHE rail train is simulated over an existing re-designed not electrified single track line in the sub-urban area of L’Aquila city (Italy). Furthermore, the specific fuel consumption comparative analysis between the hydrogen rail train and a diesel one running over the selected path in the same operating conditions has been performed and the results are discussed in terms of CO2 emissions too. The results show that the proposed LHE rail train is technically suitable and advantage to operate in urban environment.

The protection of steel parts against corrosion represents a main industrial issue. Thus, protective coatings must deal with several functional properties, and amongst them, composite zinc coatings elaboration have proven its interest. On this purpose, PMMA polymeric particles to be incorporated are synthetized by an original process. Nevertheless, due to its typical growth, zinc is known to be tricky for composite coatings elaboration. One of the possible ways to overcome this problem consists in the modification of the hydrodynamic conditions at the vicinity of the cathode, possibly with ultrasound uses. Then, after calibrating the hydrodynamic near the cathode with the equivalent flow velocity concept and characterizing the electrolyte, the zinc, zinc/PMMA, zinc/silica, and zinc/PMMA-silica coatings are elaborated under different conditions, in order to highlight how their structural properties may be affected by sonication.

This paper describes the synthesis of new 6-aminoflavone (6AFl (3)) and 6-aminochromone (6AC (4)) complexes with Cu(ii) and Ru(ii) ions ([Cu(6AC)2Cl2] (3a), [Cu(6AFl)2Cl2] (4a), [Ru(p-cymene)(6AC)Cl2] (4b)) and comparison of their properties with the previously described 7-aminoflavone (7AFl (1)) and 7-amino-2-methylchromone (7A2MC (2)) analogues. The cytotoxic effect of all these complexes against two human leukaemia cell lines (HL-60 and NALM-6), melanoma WM-115 cells and COLO205 cells, is determined. The cytotoxicity of copper(ii) complexes, especially [Cu(6AFl)2Cl2] (3a) was higher than ruthenium(ii) complexes with the same ligands. Their cytotoxic potency was also stronger in comparison to the referential agents like cisplatin. The pro-oxidative properties were determined for the most active complexes and their ability to generate ROS (reactive oxygen species)/RNS (reactive nitrogen species) in cancer cells was confirmed. The type of ligand and the chemical structure of the tested complexes had an influence on the level of ROS/RNS generated in cancer cells. The redox properties of the copper complex compounds were evaluated by cyclic voltammetry, and compared with the data for Ru(ii) complexes. The reduction and oxidation processes of Ru(iii)/Ru(ii) and Cu(ii)/Cu(i) were described as quasi-reversible.

The geometry (twist vs. planar) of a dye is one of the most pivotal factors for determining intramolecular charge transfer (ICT), light harvesting and photovoltaic properties of dye-sensitized solar cells. In order to comprehend the role of dye geometry on the above properties, we have devised the pyrene based D-π-A dyes namely 2-cyano-3-(5-pyren-1-yl-furan-2-yl)-acrylic acid (PFCC) and 2-cyano-3-(5-pyren-1-ylethynyl-furan-2-yl)-acrylic acid (PEFCC). The synthesized pyrene dyes were well characterized by NMR and EI-MS spectrometry. In both the dyes, the donor (pyrene) and acceptor (cyanoacrylic acid) segments remained the same. The varied π-spacers were furan and ethynyl furan. The influences of the ethynyl spacer on the energy levels, light absorption, dynamics of excited states and photovoltaic properties of the DSCs were systematically investigated via theoretical calculations and spectroscopic measurements. UV-visible absorption spectral measurements indicated that the introduction of the ethynyl spacer enhances the molar absorptivity of a dye (PEFCC) in the order of 2, but does not shift the absorption range, which is consistent with the results obtained from density functional theory (DFT) calculations. The theoretical analysis indicated that the charge transfer transition is mainly constituted of the HOMO to the LUMO that were found to be located on donor and acceptor segments, respectively, which is supportive for efficient charge separation and electron injection processes. TDDFT calculations highlighted that the LUMO of the PEFCC dye is more stabilized by the incorporation of the ethynyl group between the pyrene and furan moieties that aid to inject electrons efficiently into TiO2 thereby resulting in an enhanced power conversion efficiency of 2.47% when compared to the PFCC dye. Notably, the overall conversion efficiency of the PEFCC dye reached 60% with respect to that of an N719-based device (4.12%) fabricated under similar conditions. Transient absorption kinetic studies demonstrated that a slower charge recombination rate is an essential factor behind enhanced efficiencies in PEFCC based cells.

Worm gears of different purposes and dimensions belong to those objects of mechanical engineering which are connected with science intensive design works (computations and development of design arrangements) and with their not less science intensive technological realization in the course of production. In 2016 the authors published a training manual “Theory and practice of general worm gears production” (M. Infra-Engineering, 2016. – pp. 346) where there is generalized a scientific-production experience of enterprises of mechanical engineering and machine tools manufacture for the formation of the complex of modular and functionally-oriented technologies ensuring required quality and performance characteristics of such objects. As a distinctive feature of such a complex is the interconnection of design and production processes of gear basic parts: a worm, a worm wheel with similar processes in the formation of a producing surface in a gear-cutting tool for a worm wheel.

Engineering solutions intended to raise the unit capacity of the latest high-power gas-cooled turbogenerators are analyzed. Emphasis is on the intensification of air and hydrogen cooling of the stator because the temperature limitations for the indirectly cooled stator winding are determinant for this class of electrical machines.