Determination of Selected Beneficial Substances in Peach Fruits

Peaches (Prunus persica L.) are a popular and sought-after dessert fruit. This is mainly due to their flavour, aroma, attractive appearance, and high content of substances that play an important role in human nutrition. The present study was carried out to determine some important analytical properties (sugars/sucrose, glucose, fructose and sorbitol), total acid, total phenolics, flavonoids, antioxidant capacity, carotenoids and anthocyanins of 34 selected peach varieties. The analyses are also complemented by colorimetric measurements of peach skin colour using CIELAB and other chromatic parameters. The results show, for example, that all peach varieties are good sources of phenolic compounds (9.43–577 mg gallic acid equivalent (GAE).100 g−1), flavonoids (1.12–95.1 mg catechin equivalent (CAE).100 g−1), and antioxidant capacity (136–462 mg Trolox equivalent (TE).100 g−1).

Study of a surface coating present on a Renaissance Piety from the Museum of Ancient Art (Castello Sforzesco, Milan)

The surface coating present on a marble Piety dating to the Renaissance period and stored at the Castello Sforzesco-Museum of Ancient Art (Milan, Italy) was studied and chemically characterised. For this purpose, both portable non-invasive (XRF and colorimetric measurements) and micro-invasive techniques (FTIR-ATR and SEM-EDS), have been applied. The statue has been recently submitted to a restoration, since its surface appeared dark and yellowed, before an exhibition at the Louvre Museum and the original appearance of the marble surface recovered thanks to the surface coating removal. Through the analytical characterisation carried out before and after the marble cleaning, the presence of a degradation layer composed by gypsum was evidenced on the stone. The origin of this layer is ascribable to the exposure of the statue to outdoor environment and interaction with atmospheric pollution. The chemical nature of the coating applied at the end of nineteenth century also responsible for the surface alteration was hypothesized.

Chemical Degradation and Color Changes of Paint Protective Coatings Used in Solar Glass Mirrors

This paper reports a study of the influence of outdoor natural aging on paint coatings applied to the back of three commercial solar glass mirrors (A1, C2, and D2) under two different exposure environments (marine and desert) in Morocco for a period of about three years. The aging assessment was carried out through colorimetric measurements and FTIR-ATR (Attenuated total reflection-Fourier transform infrared) analyses of the top coat paints. The obtained results demonstrate that the tested coating system had a high resistance at the desert site. Under the desert environment, no obvious changes to the coating occurred after 350 days. However, at the marine site, some color changes were detected, and the coating got yellow and more matte, especially for mirror A1. FTIR-ATR analyses have indicated many modifications in the intensity of many bonds of infrared spectra especially for paint of this mirror type (A1). This chemical degradation is not only due to UV degradation but also related to many factors, such as humidity, salinity, and rainfall. This finding was concluded after the faster degradation observed on samples exposed at the marine site. The present study confirms the need to use different exposure environments for testing the limits of new protective systems for solar glass mirrors rather than using only the real service conditions. Finally, accelerated tests are necessary for understanding the effect of each degrading parameter and their results should be compared to outdoor tests data for a complete analysis of coatings durability.

A multi-analytical diagnostic approach to study patinas, trace of colours and degradation process on the stone surface of a Renaissance Piety from the Museum of Ancient Art (Castello Sforzesco, Milan)

Alteration dark patinas and traces of colours present on the surface of a marble Piety dating to the Renaissance period and stored at the Castello Sforzesco-Museum of Ancient Art (Milan, Italy) were studied and chemically characterized. For this purpose, a multi-analytical approach based on both portable non-invasive (XRF and colorimetric measurements) and micro-invasive techniques (FTIR/ATR and SEM-EDS), has been applied. The statue has been recently submitted to a restoration before an exhibition at the Louvre Museum and the original appearance of the marble surface recovered thanks to the patina removal. Through the analytical characterization carried out before and after the marble cleaning, the presence of a degradation layer composed by gypsum was evidenced on the stone surface. The origin of this layer is probably ascribable to the exposure of the statue to outdoor environment and interaction with atmospheric pollution. The chemical nature of the coating applied at the end of 19th century and responsible for the patina formation was hypothesized. Finally, the use of pigments originally applied by means of an organic binder was also highlighted.

Poly(3-HydroxyButyrate-co-3-HydroxyValerate) based Inorganic Consolidate for Firwood Preservation

The aim of this study was to address one of the major challenges of the conservation state of wooden artifacts or artworks namely, the preservation and restoration of wood surfaces. The factors involved in the deterioration of wood are mainly the external factors such as fire, low temperature and microbiological agents, which induce some degradation processes in wood, identified by discoloration, fragility and unsightly appearance. In this study, biodegradable materials based on poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBHV) and composites based on PHBHV and particles (zinc oxide (ZnO), carbonated hydroxyapatite (CHAp) and its metallic derivatives with silver (AgCHAp) and strontium (SrCHAp) were applied on firwood specimens in order to investigate their consolidation capacity. Colorimetric measurements have confirmed that the chosen treatments did not change the colour of the natural wood. The hardness test revealed that the consolidation system increases the mechanical properties of the samples. The used treatments confer a strong hydrophobic character which prevents exfoliation of the wood samples, as confirmed by the performed water absorption test.

Optimization of flexographic print properties on ecologically favorable paper substrates

Nowadays, the attention in many industries is shifting towards the problem of waste overproduction and production of the waste in general. This study aimed to find an alternative approach to the production of packaging which will be environmentally friendly and at the same time optimal in terms of the print quality. This was accomplished by using the minimal needed amount of material for the production of packaging and adjusting the parameters of the flexographic printing process to achieve the desired visual impression of the print. The designed motive for the packaging was printed on five different recycled papers, following the guidelines of sustainable design. Printing was performed on each recycled paper with different printing pressures (50N, 150N, and 400N). Smoothness was measured on each paper; and for every printed sample, colorimetric measurements and thickness of the lines in positive and negative were measured. Print contrast for each print was calculated, and microscopy of fine printed elements was performed. All chosen papers except one had average smoothnes of up to 3.2 s (the smoothest paper had the average smootheness value of 54.72 s). Smoothness results influenced the printed line widths. Specifically, when increasing the printing pressure, a significant deformation of the line width has occured on all papers except the smoothest one (deformations of the lines printed in positive were up to 400 μm for rough papers compared to maximum of 60 μm for lines printed on the smoother paper). Similar results were obtained for the lines printed in negative. Furthermore, legibility of the printed typographic elements of 4pt size was significantly influenced by the smoothness of the paper. Elements printed on the smoothest paper have displayed the negligible deformations when changing the printing pressure. For other papers, elements in positive were optimally printed by 50 N pressure, and elements in negative by the pressure of 400 N. The results of this research have enabled the optimization of the flexographic printing process when using each of the five types of recycled papers. Furthermore, the presented qualitative and colorimetric parameters of the prints enabled the assessment of the applicability of used papers as printing substrates for ecologically favorable packaging.

A Paper-Based Analytical Device for Analysis of Paraquat in Urine and Its Validation with Optical-Based Approaches

Paraquat is a highly toxic herbicide. Paraquat poisoning is often fatal and is an important public health threat in many places. The quick identification and timely initiation of treatment based on timely analysis of the paraquat concentration in urine/serum could improve the prognosis for patients. However, current paraquat concentration measurements are time-consuming and difficult to implement due to the expensive and bulky equipment required. To address these practical challenges, paper-based devices have emerged as alternative diagnostic tools for improving point-of-care testing. In this study, we demonstrate the successful use of a paper-based analytical device for the accurate detection of urine paraquat concentration. The developed paper-based analytical device employs colorimetric paraquat concentration measurements. The R2 value for the urine paraquat standard curve was 0.9989, with a dynamic range of 0–100 ppm. The limit of detection was 3.01 ppm. Two other optical-based approaches, Spectrochip and NanoDrop, were used for comparison. The results suggest that the developed paper-based analytical device is comparable to other colorimetric measurements, as determined by Bland–Altman analysis. The device was clinically validated using urine from six paraquat-poisoned patients. The results prove that the developed paper-based analytical device is accurate, easy-to-use, and efficient for urine paraquat concentration measurement, and may enable physicians to improve clinical management.