In our attempt to search for mixed alkaline-earth and transition metal arsenates, the title compound, barium dimanganese(II) bis-(arsenate), has been synthesized by employing a high-temperature RbCl flux. The crystal structure of BaMn2(AsO4)2 is made up of MnO6 octa-hedra and AsO4 tetra-hedra assembled by sharing corners and edges into infinite slabs with composition [Mn2(AsO4)2]2- that extend ...

Novel 2-benzothiazole-, 4-pyridine-, and 2- and 4-quinoline-based styryl dyes containing an N-methylbenzoaza-15(18)-crown-5(6)-ether moiety were synthesized. A detailed electronic spectroscopy study revealed high performance of these compounds as optical molecular sensors for alkali and alkaline-earth metal cations. They were shown to considerably surpass analogous chromoionophores based on N-p...

The alkaline-earth metal cyanamides MgCN* SrCN* and BaCN 2 were prepared by the reaction of melamine with the metal nitrides (M&N2, Sr-jN, Ba 3 N 2 ) at temperatures between 740 e C and 850 °C. MgCN 2 was structurally characterized by X-ray analysis using powder methods (R3m, Ζ 3 , a=327.34(1) pm, c-1412.82(5) pm). The crystal structures of S r C N 2 and BaCN 2 were determined from X-ray single...

A fast separation of alkali and alkaline earth metal cations and ammonium was carried out by capillary electrochromatography on monolithic octadecylsilica columns of 15 cm length and 100 microm inner diameter using water/methanol mixtures containing acetic acid as mobile phase. On-column contactless conductivity detection was used for quantification of these non-UV-absorbing species. The method...

a new polyvinyl choloride (pvc) membrane sensor for cerium (iii) was prepared based on 4,13-didecyl-1,7,10,16-tetraoxa-4,13-diazacyclooctadecane (kryptofix22dd) as an ionophore. the sensor exhibites a linear concentration range of 1.0×10-6to 1.0×10-1m, with a nernstian slope of 18.0±1.0 mv/decade, and a detection limit of 9.7×10-7m. it has a fast response time (5 s) and can be used for two mont...

Oxygen is one of the most important products in chemical industries. This chemical element is used in various processes such as: refinery industries, manufacturing metal and other industrial operations. For instance, oxygen with high purity is utilized in different chemical processes like: steel construction, paper industries, wastewater treatment and glass production. In 1907, oxygen was produ...

New multinary selenides Ae3SnPn2Se8 (Ae = Sr, Ba; Pn = Sb, Bi), Sr8.01Ge2.04Bi7.95Se24, and Sr8YGe2Bi7Se24 were synthesized by solid-state reaction, and their structures were determined by single-crystal X-ray diffraction. These compounds crystallize in orthorhombic space group Pnma (no. 62) for Ae3SnPn2Se8 (Ae = Sr, Ba; Pn = Sb, Bi) and in Pna21 (no. 33) for Sr8.01Ge2.04Bi7.95Se24 and Sr8YGe2B...

Understanding and manipulation of the forces assembling DNA/RNA helices have broad implications for biology, medicine, and physics. One subject of significance is the attractive force between dsDNA mediated by polycations of valence ≥ 3. Despite extensive studies, the physical origin of the "like-charge attraction" remains unsettled among competing theories. Here we show that triple-strand DNA ...