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Up one level

Application of quantum chemical method on investigate the substitution reaction nitrogen and bromate into aniline

Energies (total and electronic ones, heats of formation), charges at every atom of 49 species (reactants, transition structures,products) of the electrophilic substitutions (SE) of NO2+, Br+ into monosubstituted benzene ring C6H5NH2 were obtained by quanto-chemical calculations with semiempirical method AM1. The calculated results showed that: 1/the positions which have the higher density of electron the easier are attacked by electrophilic substituents; 2/the NH2- group of C6H5NH2 has +C > -1 effect, actutes the benzene ring and orients other electrophilic groups to the para- and ortho- positions; the substitutions to the para- position is more advantageons than to the ortho- positions; 3/species of nitronation are more stable than ones of bromination.

Capability of the graft copolymerization reaction of acrylonitrile and acrylonitrile-methyl acrylate mixtures into tapioca starch

The graft copolymerization of acrylonitrile and acrylonitrile - methyl acrylate mixtures onto natural or pretreated tapioca starch was carried out with ceric salt as initiator. The effects of acid concentration in the pretreatment and in the copolymerization on the grafting level were investigated Copolymers were characterized by FTIR.

Polystyrene - Comparing features of the synthetic products generate by using method of bulk polymerization and suspension polymerization

Polystyrene is produced by two processes: bulk polymerization and suspension polymerization. The initial benzoyl peroxide (BPO) content is 0.8-1.0 %. Polyvinyl alcol (PVA) is used as stabilizing agent. The properties of two products above were compared (include the physical property, the chemical property, the mechanical property and the electrical property).

Study on complexing of Cu(II) with xilenol orange by the photometric method and its application on determination the copper concetration in Siderfol capsule - Indian pharmacy

Study on complexing of Cu(II) with xilenol orange by the photometric method is resulted in: 1/ Optimal conditions for complexing of XO - Cu(II) system are defined; 2/ The component of complex compound Cu(II) - XO in the pH range 5.4 +- 6.4 is defined; 3/ Reaction mechanism, calibration curve, the liner range of concentration Cu (II), influence of common interfering ions are investigated; 4/ Application of results in the determination of copper in some sample matrixs.

Study on the waterproofing possibility of anti-penetration solution based on waterglass

Waterproofing mechanism of waterglass based waterproofing solution is formation of C-S-H gel what precipitates in capillaries, pores, defects and cracks in mortar and concrete. So, penetration ability of the solution is important for its waterproofing effectiveness. This paper presents the study for selection of Micro-Raman as an appropriate method for determination of penetration of waterglass based waterproofing solutions CT1 and Radcon 7. By this method, there was revealed that the penetration depth of those solutions are similar and it depends on compactness of mortar and concrete and on the way of their application.