RESUMO
The start-up, the characteristics of granular sludge and the treatment effect of an upflow anaerobic sludge blanket (UASB) reactor under mid-temperature were studied with high concentration carboxymethyl cellulose (CMC) wastewater as treating object. Experiment results showed that it spent 80 days to start up UASB by gradually increasing the influent CMC concentration, and the seed sludge was the mixture of the inoculum granular sludge and the digestion sludge. The removal rate of COD could reach above 80% when the value of influent COD concentration was 4000 mg/L and the organic loading was 6.86 kg/(m3 x d), respectively; granular sludge has been obtained in the reactor, and the specific methanogenic activity of the granular sludge was well.
Assuntos
Reatores Biológicos , Carboximetilcelulose Sódica , Compostos Orgânicos/isolamento & purificação , Eliminação de Resíduos Líquidos/métodos , Anaerobiose , Carboximetilcelulose Sódica/síntese química , Indústria Química , Resíduos Industriais , Compostos Orgânicos/metabolismo , Esgotos/químicaRESUMO
A novel detection approach named chromophore-decolorizing with free radicals is developed for determination of trace heavy metal. The hydroxyl radicals (HO) generated from Fe(III) and hydrogen peroxide will oxidize the free chromophore into almost colorless products. The copper-acid chrome dark blue (ACDB) complexation was investigated at pH 5.07. In the presence of Fe(III) and hydrogen peroxide, the excess ACDB was decolorized in the Cu-ACDB reaction solution, and the final solution contained only one color compound, the Cu-ACDB complex. After oxidation of free hydroxyl radicals, the complexation becomes sensitive and selective and it has been used for the quantitation of trace amounts of Cu(II) dissolved in natural water. Beer's law is obeyed in the range from 0 to 0.500 microg mL(-1) Cu(II) and the limit of detection is only 6 microg L(-1) Cu(II). Besides, the Cu-ACDB complex formed was characterized.
Assuntos
Compostos Azo/química , Cobre/química , Eletroquímica/métodos , Indicadores e Reagentes/farmacologia , Naftalenossulfonatos/química , Fotometria/métodos , DNA/química , Radicais Livres/química , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Indicadores e Reagentes/química , Ferro/química , Modelos Químicos , Sensibilidade e Especificidade , Espectrofotometria/métodos , Oligoelementos/químicaRESUMO
The interactions of 2', 4', 5', 7'-tetrabromo-4, 5, 6, 7-tetrachlorofluorescein (TBTCF) with BSA, ovalbumin (OVA) and poly-L-lysine (PLYS) at pH 3.70 have been investigated by combination of the spectral correction technique and the Langmuir isothermal adsorption. The active connection actions such as ion pairs, van der Waals' force, hydrogen bond, hydrophobic bond were proposed to explain the non-covalent interaction between TBTCF and BSA, OVA and PLYS. Effects of the electrolyte and high temperature indicated that union of the active connections between TBTCF and BSA and OVA was too firm to be destroyed. The relationship between the binding number of TBTCF and variety fraction of the amino acid residues was analyzed. The binding number of TBTCF depended on the number of positively charged amino acid residues. The other amino acid residues surrounded and seized TBTCF by hydrogen bonds and hydrophobic bonds when the electrostatic attraction pulled TBTCF to link protein. In addition, a novel method named the absorbance ratio difference was established for determination of protein in trace level and was applied with much higher sensitivity than the ordinary method.
