Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Adicionar filtros








Intervalo de ano
1.
Egyptian Journal of Chemistry. 2007; 50 (6): 759-770
em Inglês | IMEMR | ID: emr-112274

RESUMO

Carbamic acid 3,4 - dichlorophenyl sulfonyl methyl ester was prepared, interaction with different amines yielded a series of N-substituted-N'-3,4- dichlorophenyl sulfonylureas. Chemical structure was confirmed on the basis of elemental analysis, MS, IR and [1]HNMR spectroscopy. A pronounced herbicidal activity against Echinoocloa crus - galli L. Beauv [barnyard grass] was attained by sulfonylureas bearing pyridyl, benzoic acid - 4 - amino- and butyl moieties. Meanwhile, the corresponding phytotoxicity to Oryza straiva L. [rice] was relatively low


Assuntos
Compostos de Sulfonilureia/química , Compostos de Sulfonilureia , Herbicidas
2.
Egyptian Journal of Chemistry. 2006; 49 (2): 149-156
em Inglês | IMEMR | ID: emr-76534

RESUMO

Novel series of triethanolammonium mono- and dibenzoate bromide cationic surfactants containing different alkyl chains were synthesized. Their surface parameters including, surface tension [gamma], critical micelle concentration [CMC], effectiveness [lambada pi[cmc]], maximum surface excess gamma and minimum surface area [A [min]] were caiculated at 25 degree sign C. Increasing the number of methylene groups in the hydrophobic chains [tails] increases the surface parameters, which decreases the surface tension of these surfactants in their solutions. Energetic parameters of micellization and adsorption of these surfactants in their solutions were also calculated at 25 degree sign C. The results of thermodynamic calculations showed the tendency of these surfactant molecules towards adsorption at the air/water interfaces rather than the micellization in the bulk of their solutions. The surface and energetic parameters were correlated to the ability of these surfactants towards adsorption at the interfaces


Assuntos
Termodinâmica , Tensão Superficial , Adsorção , Brometos
3.
Egyptian Journal of Chemistry. 2005; 48 (5): 645-651
em Inglês | IMEMR | ID: emr-70479
4.
Egyptian Journal of Microbiology. 2004; 39 (1-2): 29-40
em Inglês | IMEMR | ID: emr-65717

RESUMO

Five quaternary ammonium compounds were synthesized having the formula: [C[9]H[19C[6]H[4]O-[CH[2]CH[2]O][9] -CO-CH[2]CH[2]R][+]Br [I[a-e]] where i[a]: r=triethylamine; l[b]:r = triethanolamine; l[c]:r = hexamine; l[d: r=n-methyl diethanolamine and I[c]:R = pyridine.Critical micelle concentration [CMC], effectiverness [pi[cmc]], efficiency [P[20]] and maximum surface excess [I[max]] of the novel compounds were calculated using equilibrium surface tension profiles at 25 °C. The biocidal acivity of these compounds were tested on SMC-SRB [stabilized mixed cutlrue of sulphate reducing bacteria isolated from garden soil and enriched using Postage medium B and E]. Minimal inhibitory concentration [mic] for the prepared quaternary ammonium compounds were detected for SMC-SRB using sulphide titrmetric determination method with different concentrations [10-300 ppm], using cetyl trimethyl ammonium bromide [CTAB] as a reference. It was found that triethanolamine and N-methyldiethanolamine derivatives showed the highest biocidal effect


Assuntos
Compostos de Amônio Quaternário/síntese química , Tensoativos , Tensão Superficial , Antibacterianos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA