an efficient and environmentally benign   method for the synthesis of aryl iodides have been developed by diazotization of aromatic amines with nano2 and nanosilica periodic acid (nano-spia) as a green catalyst via grinding followed by a sandmeyer iodination by ki under solvent-free conditions at room temperature. the ensuing aryl diazonium salts supported on nano-spia were sufficiently stable ...

knoevenagel condensation between barbituric acid and aldehyde was investigated in the presence of sulfonic acid functionalized nanoporous silica (sba-pr-so3h) and resulted in the formation of arylidene and bis-arylidene barbiturates. excellent yields and short reaction times are related to the high efficiency of sba-pr-so3h that the reactions take place easily in its nano-pores. sba-pr-so3h as ...

The molecular processes leading to formation of nanoparticles of blue haze over forested areas are highly complex and not fully understood. We show that the interaction between biogenic organic acids and sulfuric acid enhances nucleation and initial growth of those nanoparticles. With one cis-pinonic acid and three to five sulfuric acid molecules in the critical nucleus, the hydrophobic organic...

A highly efficient, inexpensive, recyclable, convenient, and green protocol for chemoselective aza-Michael addition reactions of amines/thiols to alpha,beta-unsaturated compounds using silica sulfuric acid (SSA or SiO(2)-SO(3)H) was developed. This method is simple, convenient and the title compounds are produced in good to excellent yields.

a number of 6-hydroxy-2-benzylidene-3-coumaranones were synthesized from condensation of 6-hydroxy-3-coumaranone with appropriate aldehydes and were evaluated for their antioxidant activities. the antioxidant activity was assessed using two methods, including, 1,1-biphenyl-2-picrylhydrazyl (dpph) radical scavenging, and reducing power assays. some of the benzylidene coumaranones showed antioxid...

The major complement-fixing antigen of Mycoplasma pneumoniae is found in the lipid fraction of the organism. When the lipids of M. pneumoniae were fractionated by column chromatography on silicic acid, serological activity against both rabbit and human immune sera was found in two fractions, B and D. Fraction B, eluted with chloroform-methanol (9:1), was a minor component in terms of total comp...

The synthesis of polymer brush decorated silica nano-particles is demonstrated by activator regeneration by electron transfer atom transfer radical polymerization (ARGET ATRP) grafting of poly(tert-butyl methacrylate). ATRP initiator decorated silica nano-particles were obtained using a novel trimethylsiloxane derivatised ATRP initiator obtained by click chemistry. Comparison of de-grafted poly...

introduction conventional water treatment consist of unit processes include coagulation, flocculation, clarification, filtration and disinfection that goal is removal of turbidity, color and certain bacterial species. in filtration process flocculated substances that have not removed in pervious stage are sediment. filter media is often silica sand that removal mechanism is complex and consists...

A novel Congo red (CR) derivatized silica stationary phase was prepared and packed into a fused silica capillary tube for nano-flow HPLC. A variety of analytes including poly-aromatic hydrocarbons, parabens, acids, sulfonamides, bases, and nucleosides were successfully separated using the CR. In comparison with commercial ODS columns, this new stationary phase has a different separation mechani...