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1.
Dalton Trans ; 52(43): 15682-15687, 2023 Nov 07.
Article in English | MEDLINE | ID: mdl-37646573

ABSTRACT

A family of robust and stable molybdenum-based metal-organic cages have been obtained based on the [Mo2O2(µ2-O)2]2+ secondary building unit. The resulting cages are decorated with different pyrdine derivatives that impart structural stability, resulting in the structural elucidation of the activated cage with single-crystal diffraction. The chemical robustness of the cage is also demonstrated by the post-synthetic modification of the cage, which allows the exchange of the pyridine derivatives without rupture of the cage.

2.
Foods ; 12(8)2023 Apr 17.
Article in English | MEDLINE | ID: mdl-37107467

ABSTRACT

There is a plethora of food products with geographical indications registered in the European Union without any study about their discrimination from other similar products. This is also the case for Greek currants. This paper aims to analyze if stable isotope analysis of C, N, and S could discriminate the Greek currants "Vositzza", registered as a product of Protected Designation of Origin, from two other currants registered as products of Protected Geographical Indication coming from neighboring areas. The first results show that the stable isotope ratio of sulfur is not detectable due to the very low sulfur content in the samples, and the analysis should be based on the stable isotope ratios of carbon and nitrogen to discriminate these products. The mean value of δ15N (1.38‱) of PDO "Vostizza" currants is lower than that of currants grown outside the PDO zone (2.01‱), while the mean value of δ13C of PDO "Vostizza" currants is higher (-23.93‱) in comparison to that of currants grown outside the PDO zone (-24.83‱). Nevertheless, the results indicate that with only two isotopic ratios, discrimination could not be achieved, and further analysis is required.

3.
J Mater Chem A Mater ; 11(10): 5320-5327, 2023 Mar 07.
Article in English | MEDLINE | ID: mdl-36911163

ABSTRACT

Two ultramicroporous 2D and 3D iron-based Metal-Organic Frameworks (MOFs) have been obtained by solvothermal synthesis using different ratios and concentrations of precursors. Their reduced pore space decorated with pendant pyridine from tangling isonicotinic ligands enables the combination of size-exclusion kinetic gas separation, due to their small pores, with thermodynamic separation, resulting from the interaction of the linker with CO2 molecules. This combined separation results in efficient materials for dynamic breakthrough gas separation with virtually infinite CO2/N2 selectivity in a wide operando range and with complete renewability at room temperature and ambient pressure.

4.
Foods ; 11(22)2022 Nov 18.
Article in English | MEDLINE | ID: mdl-36429296

ABSTRACT

Fraudulent practices are the first and foremost concern of food industry, with significant consequences in economy and human's health. The increasing demand for food has led to food fraud by replacing, mixing, blending, and mislabeling products attempting to increase the profits of producers and companies. Consequently, there was the rise of a multidisciplinary field which encompasses a large number of analytical techniques aiming to trace and authenticate the origins of agricultural products, food and beverages. Among the analytical strategies have been developed for the authentication of geographical origin of foodstuff, Inductively Coupled Plasma Mass Spectrometry (ICP-MS) increasingly dominates the field as a robust, accurate, and highly sensitive technique for determining the inorganic elements in food substances. Inorganic elements are well known for evaluating the nutritional composition of food products while it has been shown that they are considered as possible tracers for authenticating the geographical origin. This is based on the fact that the inorganic component of identical food type originating from different territories varies due to the diversity of matrix composition. The present systematic literature review focusing on gathering the research has been done up-to-date on authenticating the geographical origin of agricultural products and foods by utilizing the ICP-MS technique. The first part of the article is a tutorial about food safety/control and the fundaments of ICP-MS technique, while in the second part the total research review is discussed.

5.
Foods ; 11(19)2022 Sep 22.
Article in English | MEDLINE | ID: mdl-36230036

ABSTRACT

Consumers are increasingly interested in the geographical origin of the foodstuff they consume as an important characteristic of food authenticity and quality. To assure the authenticity of the geographical origin, various methods have been proposed. Stable isotope analysis is a method that has been extensively used for products such as wine, oil, meat, while only a few studies have been conducted for the discrimination of seafood origin and especially for mullet roes or bottarga products. Analysis of the stable isotopes of C, N and S of Bottarga samples from four different origins were carried out. The values of δ15N (5.45‱) and δ34S (4.66‱) for the Greek Bottarga Product named 'Avgotaracho Messolongiou', from Messolongi lagoon were lower than other areas while δ13C values were higher (-14.84‱). The first results show that the stable isotopes ratios of carbon, nitrogen and sulphur could be used to discriminate the Greek Protected Designations of Origin Bottarga product 'Avgotaracho Messolongiou' from other similar products.

6.
Dalton Trans ; 48(31): 11632-11636, 2019 Aug 21.
Article in English | MEDLINE | ID: mdl-31274137

ABSTRACT

The synthesis of a new {Ni8} cluster bearing tetrazolate- and azido-bridging ligands, and supported by chelating α-methyl-2-pyridine-methanol (mpmH) groups, is described herein. The reported compound has a unique trapezoidal prismatic topology, resulting from an unexpected in situ click reaction between the MeCN reaction solvent and the N3- ions under mild, room-temperature conditions. Such a click chemistry approach to the preparation of 0-D compounds is relatively unexplored and represents a fruitful strategy for the synthesis of new coordination clusters and molecule-based magnetic materials.

7.
Molecules ; 24(12)2019 Jun 13.
Article in English | MEDLINE | ID: mdl-31200586

ABSTRACT

The goal of this work is to model the nature of the chemical species [CdCl2(extractant)2] that are formed during the solvent (or liquid-liquid) extraction of the toxic cadmium(II) from chloride-containing aqueous media using hydrophobic 2-pyridyl ketoximes as extractants. Our coordination chemistry approach involves the study of the reactions between cadmium(II) chloride dihydrate and phenyl 2-pyridyl ketoxime (phpaoH) in water-containing acetone. The reactions have provided access to complexes [CdCl2(phpaoH)2]∙H2O (1∙H2O) and {[CdCl2(phpaoH)]}n (2); the solid-state structures of which have been determined by single-crystal X-ray crystallography. In both complexes, phpaoH behaves as an N,N'-bidentate chelating ligand. The complexes have been characterized by solid-state IR and Raman spectra, and by solution 1H NMR spectra. The preparation and characterization of 1∙H2O provide strong evidence for the existence of the species [CdCl2(extractant)2] that have been proposed to be formed during the liquid-liquid extraction process of Cd(II), allowing the efficient transfer of the toxic metal ion from the aqueous phase into the organic phase.


Subject(s)
Cadmium/chemistry , Chlorides/chemistry , Oximes/chemistry , Solvents/chemistry , Magnetic Resonance Spectroscopy
8.
Dalton Trans ; 48(28): 10427-10434, 2019 Jul 16.
Article in English | MEDLINE | ID: mdl-31124546

ABSTRACT

Homometallic {NiII4} cubane-like clusters with a rare chiral core have been prepared via the employment of enantiomerically pure 2-(1-hydroxyethyl)pyridine (Hmpm). Comparison with the achiral cubanes derived from the related 2-pyridinemethanol (Hpym) ligand reveals drastic structural changes as a consequence of the transfer of chirality from the ligands to the whole structure. Their magnetic properties have been related to the structural features of their cubane-type cores.

9.
Inorg Chem ; 56(6): 3568-3578, 2017 Mar 20.
Article in English | MEDLINE | ID: mdl-28267321

ABSTRACT

The introduction of the Schiff base ligand N-salicylidene-2-amino-5-chlorobenzoic acid (sacbH2) in 4f-metal chemistry has afforded a new dinuclear complex, [Dy2(NO3)4(sacbH)2(H2O)2(MeCN)2] (1), with the metal ions adopting a rare spherical tricapped trigonal prismatic coordination geometry. The deprotonated phenoxido O atoms of the organic chelate occupy the axial triangular faces of the prism and were found to be very close to the main anisotropy axes of the two DyIII ions. As a result, the {DyIII2} compound exhibits frequency- and temperature-dependent out-of-phase ac signals below ∼25 K in the absence of a static dc field, yielding an energy barrier of 109.3(1) K for the reversal of magnetization. Fast and efficient quantum tunneling of magnetization, attributed to the strong tails of signals below ∼15 K, was suppressed through the application of a small dc field, yielding entirely visible χM″ signals below 27 K. Single-crystal magnetic hysteresis studies confirmed the single-molecule magnet (SMM) behavior of 1; the hysteresis loops appear at temperatures below ∼5 K, which is one of the highest blocking temperatures in the field of 4f-SMMs to date. This joint magneto-structural and ab initio study demonstrates the ability of more common coordination numbers (i.e., 9), but with rare coordination geometries (i.e., spherical tricapped trigonal prismatic), to promote axiality that enhances the molecular anisotropy and subsequently the magnetization dynamics of the system.

10.
Dalton Trans ; 43(30): 11456-60, 2014 Aug 14.
Article in English | MEDLINE | ID: mdl-24816838

ABSTRACT

The first use of the flexible Schiff base ligand N-salicylidene-2-aminocyclohexanol in metal cluster chemistry has afforded a new family of Ln7 clusters with ideal D(3h) point group symmetry and metal-centered trigonal prismatic topology; solid-state and solution studies revealed SMM and photoluminescence behaviors.

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