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Wioletta Drożdż, Hanna Boruczkowska, Tomasz Boruczkowski, Ewa Tomaszewska-Ciosk and Ewa Zdybel

Abstract

Fruit and vegetable processing by-products, undervalued until recently, are rich sources of nutrients. This study investigated properties of extruded corn puffs with addition (5–20%) of blackcurrant or chokeberry pressings. We assessed expansion rate, water absorption index (WAI) and water solubility index (WSI) of the produced extru-dates, the concentration of polyphenols, and antioxidant activity measured by FRAP method and ABTS method. The puffs with addition of chokeberry pressings had higher WSI values, higher phenolic acids, flavonols, and anthocyanins content, and higher antioxidant activity than puffcorn with addition of blackcurrant pressings. The corn puffs with addition of fruit pressings contained much higher concentrations of phenolic compounds and were characterized by much higher antioxidant activity than pure puffcorn. This confirms the usefulness of addition of such fruit processing by-products in order to manufacture functional food.

Open access

Maciej Mrówka, Tomasz Machoczek, Paweł Jureczko, Małgorzata Szymiczek, Magdalena Skonieczna and Łukasz Marcoll

Abstract

The purpose of the conducted study was to analyse new materials intended for contact with the human body in view of their physical, chemical and biological properties. The authors have put to test six commercially available materials, four out of which were composite polyamide 12-based materials, while two were polyurethanes. The examined materials were assessed in terms of the surface. Subsequently, their hardness and biocompatibility were tested. The authors devoted major attention to the tests of absorption and emissivity of water, the pH = 7.4 PBS buffer solution and pH = 4.3 artificial sweat in temperatures of 21°C and 37°C. The results of the tests have confirmed the non-toxicity of all the tested materials and allowed to provide their characteristics in terms of their surface, hardness, as well as absorption and emissivity of various body fluids. Both polyamide 12 and the tested polyurethanes are classified as thermoplastics that may be used in additive technology.

Open access

H. Geiplová, L. Mindoš, J. Mrázek, D. Majtás, P. Macová and P. Pokorný

Abstract

The paper follows the paper describing the condition of wrought iron structure of main railway station [1]. In this paper the investigation of condition of paint system corrosion surface treatment is given and the restoration procedure is described. The withdrawal samples of paint systems were analysed by stratigraphy, FTIR and XRF analysis. Due to identification of Pb pigment presence in primer the water jet technology was chosen which minimalised the danger waste formation.

Open access

P. Pokorný, M. Hrabánek and H. Geiplová

Abstract

This article presents the results of the corrosion survey of the load-bearing structure of the main hall of the Main railway station in Prague. The chemical composition and microscopy view of the metal alloy has been explored, the current state of the anti-corrosion protection system as well as its composition were also evaluated. The corrosion damage of sheets and reinforcements of individual columns of the peron hall is also reported. The corrosion damage of the plates and reinforcements is locally very significant and is related to the drainage of rain water from the damaged roof structure. Renovation is also necessary for the protective coating system. The article concludes a restoration project that fully respects the historical form of the construction of the early twentieth century with minimal compromise.

Open access

Junyi Hu, Aiqiang Guo, Yingqian Xu, Changsheng Pan, Xingfu Wei, Longlong Wang and Guoyong Xiao

Abstract

α-Damascone is widely used in perfumes. However, the manufacture of α-damascone remains challenging owing to the limitations of current production processes. Herein, α-damascone was successfully synthesized from α-ionone using a new route involving only four steps, namely oximization, epoxidation, dehydration, and reduction. The total yield was 54.9% with a final chemical purity of 97% (by GC). Only water, cyclohexane, and ethanol were used in the reactions except in the purification step, and all solvents could be recycled. The structures of the intermediates and target compound were identified by 1H NMR and 13C NMR analyses and MS experiments. This route is a simple and successful method for the industrial preparation of α-damascone.

Open access

Damian Milde, Leszek Urbańczyk, Marcin Figura and Wojciech Piś

Abstract

The polyphosphoric acids (PPA) were synthesized in a cascade reactors system from P2O5 obtained from the burning of Kazakh phosphorus. Presented system provides guidelines for the PPA production process using phosphoric acids only at concentrations above 100% (in conversion to H3PO4). Polyphosphoric acids are processed in a cascade reactors system, where the in 1st concentration of PPA is increased by addition of P2O5, while in the 2nd reactor PPA is diluted with the use of 85% phosphoric acid. Produced PPA can be obtained in the 100–118% range and is characterized by high chemical purity due to the reduction of the corrosivity of the reaction, which results in very low content of iron (below 2 ppm Fe).

Open access

Paulina Pianko-Oprych and Mateusz Palus

Abstract

The objective of the study was to develop a steady-state system model in Aspen TECH using user-defined subroutines to predict the SOFC electrochemical performance. In order to achieve high overall fuel utilization and thus high electrical efficiency, a concept of Combined Heat and Power system with two-stage SOFC stacks of different number of cells was analyzed. The concept of two-stage SOFC stacks based system was developed in the framework of the FP7 EU-funded project STAGE-SOFC. The model was validated against data gathered during the operation of the proof-of-concept showing good agreement with the comparative simulation data. Following model validation, further simulations were performed for different values of fuel utilization to analyze its influence on system electrical performance. Simulation results showed that the concept of two-stage SOFC stacks configuration was viable and reliable. The model can be useful for development the optimal control strategy for system under safe conditions.

Open access

Zofia Nizioł-Łukaszewska, Tomasz Bujak, Tomasz Wasilewski and Edyta Szmuc

Abstract

Jerusalem artichoke (Helianthus tuberosus) and chicory (Cichorium intybus) are valuable pharmaceutical raw materials on account of their high content of inulin, a natural prebiotic. Inulin-rich plants are also increasingly employed in the formulation of cosmetic products. The paper presents the biological properties of aqueous and aqueous-ethanolic extracts of Jerusalem artichoke and chicory. The extracts have been found to have a high free radical scavenging ability, with the most beneficial antioxidant properties being observed for the aqueous-ethanolic extract of Jerusalem artichoke. Inulin isolated from both plant types is a safe and non-toxic raw material. Inulin added to model body wash gel formulations markedly reduces their potential to cause skin irritation and sensitization.

Open access

K. C. Strachotová, M. Kouřil, K. Kuchťáková and Š. Msallamová

Abstract

Lead in archive environment suffers from severe corrosion attack caused by the organic acids’ vapours usually presented in such an environment. One of possible ways of corrosion protection of lead is its surface treatment by solutions of sodium salts of monocarboxylic acids (general formula CH3(CH2)n-2COONa, noted NaCn, n = 10, 11, 12). The principle of this corrosion protection is a creation of conversion coating on the lead’s surface, which decreases corrosion rate of lead in the atmospheric environment polluted by organic acids’ vapour. Our research aims at the selection of a suitable protection system that would be applicable to conservation of historical lead in archives and museums. This paper evaluates the corrosion behaviour of treated lead based on the values of polarisation resistance and shape of potentiodynamic curves in simulated corrosive environment (0.01 mol l−1 solution of acetic acid). The lead samples with different state of surface (pure, corroded and electrochemically cleaned) were treated with sodium salts of monocarboxylic acids NaCn (n = 10, 11, 12) having concentration of 0.01 and 0.05 mol l−1. In simulated corrosive atmosphere (above 0.001 mol l−1 acetic acid solution vapours), corrosion rate was measured by means of electrical resistance technique. The inhibition efficiency of monocarboxylic acids is dependent on their carbon chain length and their concentration. The greatest inhibiting efficiency in corrosive atmospheres and for all lead samples was observed for the sodium salt of dodecanoic acid having concentration of 0.05 mol l−1. Artificially created corrosion products and salt coatings were analysed by X-ray diffraction analysis and their surface morphology was observed by scanning electron microscopy. A protective salt coatings are mainly composed of metallic soaps in dimer form.

Open access

P. Pokorný and M. Kouřil

Abstract

In this paper, the influence of calcium cations on the corrosion behavior of hot-dip galvanized steel in model concrete pore solutions is evaluated by means of conventional electrochemical methods (measurement of free corosion potencial and polarization resistance), surface analysis methods (optical and confocal microscopy) and XRD phase analysis of precipitated corrosion products. The results of these experiments confirm the conclusions of the current work on a similar topic, i.e. the crystalline calcium based corrosion products Ca[Zn(OH)3]2·2H2O are not able passivate effectively surface of hot-dip galvanized steel in model of concrete pore solutions (pH 12.6; 13.0). If passivation occurs, a mixed Ca[Zn(OH)3]2·2H2O, ZnO and Zn(OH)2 is involved.