RESUMO
In this paper, flocculating performance and mechanisms of a new composite coagulant, poly-ferric aluminum chloride-polydimethyl diallylammonium chloride (PFAC-PD) with different OH-/(Fe3+ + Al3+) molar ratios, were investigated for humic acid (HA)-kaolin synthetic wastewater treatment. The impact of OH-/(Fe3+ + Al3+) molar ratios on the removal efficiencies of turbidity and dissolved organic carbon, specific UV absorbance, coagulation mechanisms and dynamics was explored during the coagulation process using composite coagulants. The coagulation experimental results revealed that the composite coagulants with lower OH-/(Fe3+ + Al3+) molar ratio exhibited better coagulation efficiency. When OH-/(Fe3+ + Al3+) molar ratio of the composite coagulant was 1.5, adsorption-bridging played a dominant role in coagulating HA-kaolin synthetic wastewater. The floc growth rate and floc size, increased with increasing OH-/(Fe3+ + Al3+) molar ratio and the highest peak height of the size distribution was obtained by PFAC-PD with OH-/(Fe3+ + Al3+) = 1.5. Also, the composite coagulants with higher OH-/(Fe3+ + Al3+) molar ratio formed more compact flocs, as reflected by the higher fractal dimension value. The flocs coagulated by PFAC-PD with basicity value of 1.0 gave strong strength and good recoverability.
Assuntos
Compostos de Alumínio/química , Precipitação Química , Cloretos/química , Compostos Férricos/química , Polietilenos/química , Compostos de Amônio Quaternário/química , Poluentes Químicos da Água/química , Adsorção , Alumínio , Cloreto de Alumínio , Floculação , Substâncias Húmicas , Caulim , Eliminação de Resíduos Líquidos , Águas ResiduáriasRESUMO
This study was aimed to examine the expression of apoptosis-associated gene Fas in HeLa cell, explore the effects of the co-immobilized cytokines (tumor necrosis factor-alpha and interferon-gamma), and probe the potential mechanism of action. The preparation and application of the research couple IFN-gamma and TNF-alpha to the polystyrene cell culture plate were performed using the Photo-immobilization method, with different doses (20 ng/well and 200 ng/well) and synthesized optical active material. HeLa cells were treated with cytokines for two dose and 1, 3, 6 days. The result showed that the free cytokines induced HeLa apoptosis quickly, yet the HeLa apoptosis induced by co-immobilized cytokines had longer effect.
