<abstract xmlns="http://www.w3.org/1999/xhtml">Different types of 1D and 2D NMR experiments were used to completely characterize quinic acid and demonstrate its presence in complex mixtures. The identification of quinic acid in apple juice was done without any separation step. The NMR experiments presented in this study can be used to analyze other metabolites in different complex natural fluids, of vegetal or biological origin.</abstract>

“Petru Poni” Institute of Macromolecular Chemistry, Romanian Academy, Group of Biospectroscopy, Aleea Grigore Ghica 41-A, RO-700487 Iasi, Romania

“Costin D. Nenitescu” Centre of Organic Chemistry, Romanian Academy, Group of Biospectroscopy, Spl. Independentei 202-B, RO-060023 Bucharest, Romania

“Ovidius” University of Constanta, Department of Chemistry and Chemical Engineering, Bd. Mamaia 124, RO-900527 Constanta, Romania

NMR detected metabolites in complex natural fluids. Quinic acid in apple juice

<abstract xmlns="http://www.w3.org/1999/xhtml">Milk consumption is important in the diet of all age groups because it provides important nutrients that are essential for humans. Children are the largest consumers of milk, thus, it’s very important that milk is free of toxic compounds that can be harmful for humans. Aim of the study was to determine the physico-chemical characteristics of some samples of milk powder for different stage of baby growing and for some samples of fresh milk: raw cow’s milk, milk trade and UHT type. The following physico-chemical properties: density, pH, acidity, the presence of acetone, enzymes, antiseptics, dry substance, the ash, total fat, saponification and peroxide index, total nitrogen and protein content were determined. Comparing the values of acidity for analyzed samples it can be concluded that the powder milk acidity value is much lower than the fresh milk. The presence of antiseptics and acetone was not identified, and amylase and peroxidase were found only in raw cow's milk. The highest protein content was found for milk powder (27.22%).</abstract>

Physico-chemical characterisation of some samples of fresh milk and milk powder

<abstract xmlns="http://www.w3.org/1999/xhtml">In our recent studies, we have investigated the tunability of optical properties of zinc oxide nanoparticles (ZnO NPs) through surface modification with organosilane surfactants. In the present paper, the effect of ZnO NPs modified with variable amount of 3-(trimethoxysilyl)propylmethacrylate (MPS) surfactant was investigated toward the photocatalytic degradation of methylene blue (MB), using two different UV light sources emitting at 254 nm and 365 nm. While the maximum photodegradation efficiency of 63% was reached by ZnO NPs loaded with the highest concentration of MPS upon exposure at 254 nm, in the case of UV exposure at 365 nm an opposite photodegradation trend was observed. Actually, a significant photodegradation efficiency of 95% was recorded by the unmodified ZnO, followed by ZnO NPs modified with 2% MPS for which the photodegradation efficiency amounted to 80%, thus highlighting their best photocatalytic performance.</abstract>

Photocatalytic study of organosilane-modified zinc oxide nanoparticles

<abstract xmlns="http://www.w3.org/1999/xhtml">The offered article explores various research studies, developed patents in terms of physical and chemical approaches to the activation of fuel. In this regard, national and foreign researches in the field of fuels activators with different principles of action were analysed, evaluating their pros and cons. The article also intends to classify these methods and compare them regarding diverse desired results and types of fuels used. In terms of physical and chemical influences on fuels and the necessity of making constructive changes in the fuel system of internal combustion engines, an optimal approach was outlined.</abstract>

University of Hull, Hull, School of Politics, Philosophy & International Relations, Cottingham Road, Hull, UK, HU6 7RX

National Aviation University, Institute of Environmental Safety, Kosmonavta Komarova Ave 1, Kyiv, Ukraine, 03680

Analysis and classification of physical and chemical methods of fuel activation

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Ovidius University Annals of Chemistry

 We are pleased to announce that Ovidius University Annals of Chemistry was accepted to Emerging Source Citation Index by Clarivate Analytics (Thomson Reuters). Ovidius University Annals of Chemistry is an open access journal, published as electronic open volume. It was founded in 1990 by the Department of Chemistry and Chemical Engineering, Ovidius University of Constanta, Romania.The biannual journal publishes peer-reviewed original research articles and reviews in all fields of fundamental and applied chemistry. The articles are published on the journal’s website as soon as they are accepted for publication.  Archiving  Sciendo archives the contents of this journal in Portico - digital long-term preservation service of scholarly books, journals and collections.  Plagiarism Policy  The editorial board is participating in a growing community of Similarity Check System's users in order to ensure that the content published is original and trustworthy. Similarity Check is a medium that allows for comprehensive manuscripts screening, aimed to eliminate plagiarism and provide a high standard and quality peer-review process. 