A solid acid membranes based on poly (vinyl alcohol) (PVA), sodium bromide (NaBr) and phosphoric acid (H3PO4) were prepared by a solution casting method. The morphological, IR, electrical and optical properties of the (PVA)0.7(NaBr)0.3(H3PO4) x M solid acid membranes where x = 0.00, 0.85, 1.7, 3.4, 5.1 M were investigated. The variation of film morphology was examined by scanning electron micro...

The privileged spiro[pyrrolidin-3,3'-oxindole] derivatives exhibit important biological activities. An enantioselective organocatalytic approach to the rapid synthesis of spiro[pyrrolidin-3,3'-oxindole] derivatives with high enantiopurity and structural diversity is described. The asymmetric catalytic three-component 1,3-dipolar cycloaddition of a broad range of methyleneindolinones with aldehy...

THE phosphatase obtained from the bones of growing animals has proved very useful in the study of the chemical composition of phosphoric esters of biochemical interest. By its aid the phosphoric acid groups may be quantitatively removed under conditions of pH and temperature which do not involve the rupture of other linkages in the molecule such as would occur during acid hydrolysis. For such p...

We report here the first catalytic asymmetric thioacetalization of salicylaldehyde and dithiol. Chiral phosphoric acid STRIP C5 is identified as a powerful catalyst for this reaction to afford various chiral dithioacetals in high to excellent yields and enantioselectivities under mild conditions.

In this study, the adsorption of Reactive blue 19 onto pomegranate residual-based activated carbon PRAC was investigated in aqueous solution. The activated carbon prepared by phosphoric acid activation under air condition. PRAC was characterized for its surface chemistry by point of zero charge measurements, Scanning Electron Microscopy and nitrogen adsorption at 77 K. The effect of operational...

Introduction Soft drinks are complex mixtures containing a variety of substances such as coloring compounds, flavoring agents, acidifiers, sweeteners, preservatives, and caffeine. Acidulants reduce the soft drink’s pH and thereby assist in beverage preservation for long-term storage. Acidulants can also be used as chelating agents, buffers, coagulators, and flavoring agents. In the latter role,...