Here, for the first time, it is reported that some Mn oxides after a few hours convert to a nanolayered Mn oxide when the compounds are used as water-oxidizing catalysts in a water electrolysis device at near neutral pH and in the presence of LiClO4. The new nanolayered Mn oxide is more active than other Mn oxides toward water oxidation. This result is very important for artificial photosynthet...

The determination of halides is of interest in many chemical investigations. For example, in a recent determination of the atomic weight of chlorine[l] * it was necessary to determine the chloride content of dilute solutions with high precision. For such applications, coulometric titration is particularly advantageous because it involves a minimum of manipulation. A further advantage is that th...

Solid titration was used to explore the solubility isotherms of partially (Srx-HAp, x=1, 5, 10, 40, 60 mol.%) and fully substituted strontium hydroxyapatite (Sr-HAp). Solubility increased with increasing strontium content. No phase other than strontium-substituted HAp, corresponding to the original titrant, was detected in the solid present at equilibrium; in particular, dicalcium hydrogen phos...

New rapid, sensitive and simple electrometric method was developed to determine sertraline hydrochloride (Ser-Cl) in its pure raw material and pharmaceutical formulations. Membrane sensors based on heteropolyacids as ion associating material were prepared. Silicomolybdic acid (SMA), silicotungstic acid (STA) and phosphomolybdic acid (PMA) were used. The slope and limit of detection are 50.00, 6...

A multicopper oxidase gene, cumA, required for Mn(II) oxidation was recently identified in Pseudomonas putida strain GB-1. In the present study, degenerate primers based on the putative copper-binding regions of the cumA gene product were used to PCR amplify cumA gene sequences from a variety of Pseudomonas strains, including both Mn(II)-oxidizing and non-Mn(II)-oxidizing strains. The presence ...

The oxidizing anticancer system of vitamin C and vitamin K₃ (VC:VK₃, producing hydrogen peroxide via superoxide) was combined individually with melatonin, curcumin, quercetin, or cholecalciferol (VD₃) to determine interactions. Substrates were LNCaP and PC-3 prostate cancer cell lines. Three of the tested antioxidants displayed differences in cell line cytotoxicity. Melatonin combined with VC:V...

Substituted 2, 4- diphenyl quinolines were synthesized by a multicomponent domino reaction of anilines, aldehydes and terminal aryl alkynes. The synthetic pathway involves the formation of an imine, followed by the intermolecular addition of an alkyne to the imine. This intermediate immediately undergoes ring closure and oxidative aromatization. The reaction is catalyzed by natural kaolin, a st...

reactions of 1 ,zdihydropyridines (la-c) and 1,4-dihydropyridines (2a-c) in the presence of benzyne (3) under thermal conditions, and in the case of (2c) under photochemical conditions, have been investigated. benzyne acts as an oxidizing agent to convert dihydropyridine (la) and (2a) to the corresponding pyridine (4) or adds as a dienophile to (lb-c).

The blue triangle nanosilver (BAgNP) sol was prepared by the two reducers of NaBH4 and H2O2. Using BAgNP as the precursor, a small spherical nanosilver (AgNP) sol in yellow was synthesized by addition of suitable amounts of X (-) (X = Cl, Br, and I). The oxidization process of BAgNP to AgNP was studied in detail by resonance Rayleigh scattering (RRS), surface-enhanced Raman scattering (SERS), l...

Novel strains of obligately chemolithoautotrophic, sulfur-oxidizing bacteria have been isolated from various depths of Lake Fryxell, Antarctica. Physiological, morphological, and phylogenetic analyses showed these strains to be related to mesophilic Thiobacillus species, such as T. thioparus. However, the psychrotolerant Antarctic isolates showed an adaptation to cold temperatures and thus shou...