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A novel methodology is developed for the evaluation of receptor arrangement in structurally flexible anion chemosensors and is applied to map the binding site of a new pseudocyclic tristhiourea chemosensor. The binding patterns are found to be different for the chemosensors, indicating dissimilarity in the arrangement of the binding sites of pseudocyclic tristhiourea chemosensor and macrocyclic chemosensor.

Research has been conducted on the furcated modular units of the type AB (sub)2 or ABB', possible monomers used in constructing the branched oligomers. The synthesis of the AB (sub)2 type units suitable for the ether-linked dendrimer construction has been performed via a divergent strategy and the results are reported.

Effective and clean routes are described for constructing poly(aryl benzyl ether), poly(aryl benzyl thioether) and poly(aryl benzyl amine) dendrons on polystyrene beads from readily available starting materials. The analysis has demonstrated the influence of the coordination ability of the backbone on the activity of a supported dendritic catalyst.

• Uranium and cerium containing samples were examined as part of an international nuclear forensics exercise. • The main technique for characterization was the combined analysis by SEM-EDS/Raman of the surface. • Connection between the ingots was determined by uranium and cerium isotopic ratios as well as yttria and graphite surface contaminations. • Sample preparation history was interpreted based on surface contaminations, showing multiple impurities present in suggested production and processing sites. The objective of this paper is to describe nuclear forensics material characterization, as conducted in the Israeli National Nuclear Forensic Laboratory (INNFL) during an international exercise Collaborative Material Exercise 6 (CMX6) organized by the Nuclear Forensics international technical working group (ITWG). The characterized materials are uranium and cerium metal ingots. The goal was characterization of physical parameters, elemental and isotopic composition, morphology and chemical composition of the surface. Electron microscopy and Raman spectroscopy techniques were combined for morphological, structural and elemental study of the surface. The information from these analyses was used to answer the exercise questions, comparing the materials (labeled ES-1 and ES-2) to each other and to other samples described in the scenario. The INNFL investigation identified a connection between ES-1 and ES-2 based on several indicators, including the isotopic composition of the uranium present in both samples, as well as other surface contaminations, mainly yttria and graphite. Based on these finding the INNFL established a connection between ES-1 and ES-2 to ES-3B (theoretical sample with uranium traces) and has not established a connection to ES-3A (theoretical sample of plutonium powder). ES1 and ES-2 have been suggestively connected to their theoretical source, by their isotopic ratio. The INNFL conclusion was that the theoretical source materials (oxide and fluoride) were converted into the actual materials. [Display omitted] [ABSTRACT FROM AUTHOR]