calixarenes are a readily available and important class of macrocycles in supramolecularchemistry. calixarenes have generated considerable interest due to their basket shaped structureand as useful building blocks to synthesize selective receptors for the guest species, notably alkali,alkaline earth, lanthanide and transition metal cations. in this work studied on the complexingproperties of a ...

Collective surface excitations in alkali-metal overlayers are observed using photoyield spectroscopy. Spectra for Na and K on Al~111! reveal a multipole surface plasmon and bulklike overlayer plasmon. In contrast, Li on Al exhibits only the multipole mode. In the submonolayer regime, all three alkali metals provide evidence for the threshold excitation. Time-dependent density-functional calcula...

We report the first direct solution NMR detection of the alkali metal cations (23Na+, 39K+, and 87Rb+) residing inside G-quadruplex channel structures formed by guanosine 5'-monophosphate and a DNA oligomer, d(TG4T). In solution, these channel alkali metal cations are tightly bound to the G-quadruplex structure and have been considered to be "invisible" to NMR spectroscopy for many years. Our f...

In the present study we have synthesized new trinuclear complexes of alkali metal salts with interaction of stable metal chelates of violuric Acid of Ni(II) & Cu(II) having general formula [Ma(H2Va)2.(MbL)2] and [Ma(H2Va)2.(MbX)2] where Ma=Ni (II) or Cu(II) and Mb =Li + , Na & K , H2Va= deprotonated Violuric Acid , L=deprotonated 1-nitroso-2-naphthol or 8-hydroxyquinoline and, X= ClO-4 or SCN ....

In the present study we have synthesized new binuclear complexes of alkali and alkaline earth metal salts with interaction of stable metal chelates of isonitrosopropiophenone of Ni(II) & Cu(II) having general formula [Ma(INPP)2.MbL] and [Ma(INPP)2.MbX] for alkali metal adducts and [ Ma(INPP)2.MbL2] and [ Ma(INPP)2.MbX2] for alkaline earth metal adducts where Ma=Ni (II) or Cu(II) and Mb =Li+ , N...

In vivo biosensing requires stable transistor operation in high-salt concentration bodily fluids while exhibiting impermeability to mobile alkali ions that would otherwise render the metal-oxide-semiconductor (MOS) threshold voltage to drift. Metal oxide semiconductor capacitor structures using Al2O3 as the gate dielectric were soaked in a sterile physiological buffer solution (PBS) up to 24 ho...

synthesis and cation selectivity of 25, 27, dipropoxy-26, 28, di-propoxy 5, 11, 17, 23, ptert-butyl calix[4]arene are studied in acetonitrile solution. the stability constants of differentcomplexes of calixarene (as a ligand) with alkali metal cations are determined at 25 °c by usingspectrophotometric technique.on the basis of calculations, complexation of calixarene with cs+and li+ are more fa...

Ultrathin 2D metal alloy nanomaterials have great potential applications but their controlled syntheses are limited to few noble metal based systems. Herein Ni x Co1-x alloy nanosheets with ultrathin (sub-3 nm) single-crystalline 2D structure are synthesized through a topochemical reduction method. Moreover, the optimized composition Ni0.6Co0.4 alloy nanosheets array exhibits excellent performa...

Alkali metal cations can interact with Fe-N2 complexes, potentially enhancing back-bonding or influencing the geometry of the iron atom. These influences are relevant to large-scale N2 reduction by iron, such as in the FeMoco of nitrogenase and the alkali-promoted Haber-Bosch process. However, to our knowledge there have been no systematic studies of a large range of alkali metals regarding the...