Reaction of chloroacetylenephosphonates with 5-thiotetrazoles

1-Chloroacetylene-2-phosphonates react with 1-substituted 5-thio-1H-1,2,3,4-tetrazoles in anhydrous acetonitrile to form new fused heterocycles, 6-(dialkoxyphosphoryl)-3H-[1,3]thiazolo[3,2-d][1,2,3,4]tetrazol-7-ium chlorides, with a small quantity of Z-dialkyl (1,2-bis{[1-amino(methyl/phenyl)-1H-tetrazol-5-yl]sulfanyl}ethenyl)phosphonates.     

Synthesis and Characterization of Niobium-Bearing Members of the NZP and NbOPO 4 Structural Families

Theoretically predicted by us, M 1/3 Nb 5/3 (PO 4 ) 3 (M = Mg, Mn, Co, Ni, Cu or Zn) compounds with the sodium zirconium phosphate (NZP) framework structure having no interstitial ions were synthesized. The rising of temperature above 900;C causes the change of chemical composition of NZP compounds and formation NbOPO 4 -like products. The phase formation regularities stated gave a possibility to choose optimal conditions for preparation of these phosphates.     

Consecutive expansions of -out-of- systems

We introduce consecutive expansions of k–out–of–n systems, which have the property that components are totally ordered by the node criticality relation and with respect to well-known structural importance measures. We propose some formulae to easily compute these measures and study the hierarchies induced for them for large systems.     

Soft template synthesis of cobalt(III) chelates with 2,8-dithio-3, 7-diaza-5-oxa-nonandithioamide-1,9 and with 2,7-dithio-3,6-diazaoctadien-3, 5-dithioamide-1,8 into cobalt(III)hexacyanoferrate(II) gelatin-immobilized matrix materials

The complexing processes in the triple Co^III–dithiooxamide–methanal and Co^III–dithiooxamide–glyoxal systems taking place in the KCoFe(CN)₆-gelatin-immobilized matrix in contact with aqueous-alkaline solutions (pH~12) containing (dithiooxamide + methanal) and (dithiooxamide + glyoxal), have been studied. Template synthesis leading to macrocyclic Co^III coordination compounds with tetradentate N,N,S,S-donor ligands-(2,8-dithio-3,7-diaza-5-oxanonandithioamide-1,9) and (2,7-dithio-3,6-diazaoctadien-3,5-dithioamide-1,8) occurs under these specific conditions. Dithiooxamide, methanal and glyoxal are the ligand synthons in these processes.     

An Overview of the Antimicrobial Properties of Lignocellulosic Materials

Pathogenic microbes are a major source of health and environmental problems, mostly due to their easy proliferation on most surfaces. Currently, new classes of antimicrobial agents are under development to prevent microbial adhesion and biofilm formation. However, they are mostly from synthetic origin and present several disadvantages. The use of natural biopolymers such as cellulose, hemicellulose, and lignin, derived from lignocellulosic materials as antimicrobial agents has a promising potential. Lignocellulosic materials are one of the most abundant natural materials from renewable sources, and they present attractive characteristics, such as low density and biodegradability, are low-cost, high availability, and environmentally friendly. This review aims to provide new insights into the current usage and potential of lignocellulosic materials (biopolymer and fibers) as antimicrobial materials, highlighting their future application as a novel drug-free antimicrobial polymer.     

Contact angle hysteresis on polymer substrates established with various experimental techniques, its interpretation, and quantitative characterization

The effect of contact angle hysteresis (CAH) was studied on various polymer substrates with traditional and new experimental techniques. The new experimental technique presented in the article is based on the slow deformation of the droplet, thus CAH is studied under the constant volume of the drop in contrast to existing techniques when the volume of the drop is changed under the measurement. The energy of hysteresis was calculated in the framework of the improved Extrand approach. The advancing contact angle established with a new technique is in a good agreement with that measured with the needle-syringe method. The receding angles measured with three experimental techniques demonstrated a very significant discrepancy. The force pinning the triple line responsible for hysteresis was calculated.     

Disorder–order phase transition in nanocrystalline titanium monoxide with two-sublattice ordering of structural vacancies

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Size effect in nonstoichiometric titanium monoxide and vanadium carbide nanocrystals measured by positron lifetime spectroscopy

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Venom-Derived Neurotoxins Targeting Nicotinic Acetylcholine Receptors

Acetylcholine was the first neurotransmitter described. The receptors targeted by acetylcholine are found within organisms spanning different phyla and position themselves as very attractive targets for predation, as well as for defense. Venoms of snakes within the Elapidae family, as well as those of marine snails within the Conus genus, are particularly rich in proteins and peptides that target nicotinic acetylcholine receptors (nAChRs). Such compounds are invaluable tools for research seeking to understand the structure and function of the cholinergic system. Proteins and peptides of venomous origin targeting nAChR demonstrate high affinity and good selectivity. This review aims at providing an overview of the toxins targeting nAChRs found within venoms of different animals, as well as their activities and the structural determinants important for receptor binding.