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Sludge Concentration (MLSS) is one of major parameters for operation of Anoxic/Aerobic-Membrane Bioreactors（A/O-MBR）and it influences the removal efficiency of pollutants and the rate of membrane fouling as well. This paper focuses on the effects of different MLSS on the treatment of domestic wastewater, the quantity and composition of extracellular polymeric substance (EPS), and the variation of the rate of membrane fouling. It also includes a preliminary analysis of the correlation between EPS and membrane fouling to provide reference for future studies of the mechanism of membrane fouling.

Micro-structure injection molding machine is mainly used for processing the plastic products in micron-size or with micro-structures. This paper focuses on the design and control of the clamping mechanism of micro-structure injection molding machine. Firstly, the deformation of the clamping mechanism was analyzed. The simulation results shows that the clamping force is 5.0051×105N, and it’s bigger than the design value 500kN. Secondly, the kinetic characteristic of the clamping was simulated by ADAMS software. The curves of the displacement, velocity, clamping force of moving platen were analyzed. Thirdly, the control model of clamping mechanism was established. And the LQR controller was designed and simulated by Matlab. The rise time is 0.010s, the settling time is 0.026s and the steady-state is 0.307m.

To investigate the protective effects and the possible molecular mechanisms of chlorogenic acid on H2O2-induced dysfunction and apoptosis in human umbilical vein endothelial cells (HUVECs). HUVECs were divided into three groups: H2O2groups (0, 5, 10, 20, 50mM), chlorogenic acid (100nmol/L) groups and atorvastatin (10μmol/L) groups. The eNOS mRNA expression was measured by RT-PCR. The content of NO in the supernatant was detected by the nitrate reductase assay. Cells activity was evaluated by the MTT assay. The level of reactive oxygen species (ROS) in cells was measured using H2DCF-DA as a fluorescence probe. Results demonstrated that H2O2caused a significant down-regulation of eNOS mRNA expression and decreased the secretion of NO in a dose-dependent manner compared with the control group. Furthermore, H2O2 induced cell apoptosis, increased ROS accumulation. Nevertheless, these effects of H2O2could be blocked by chlorogenic acid in chlorogenic acid pretreatment groups. CONCLUSION:chlorogenic acid can inhibite H2O2-induced dysfunction and apoptosis in HUVECs, which may be related to its effects on suppressing oxidative stress, up-regulating eNOS pathway. These results suggest the usefulness of chlorogenic acid particularly in the treatment of cardiovascular disease.

Anoxic/Oxic Membrane Bioreactor (A/O-MBR) was used to treat domestic sewage, the effect of different sludge retention time (SRT) on nitrogen removal and the sludge properties were investigated. The results indicated that the change of NH3-N removal increased gradually with the SRT extension, then basically tends to be stable. The systematic elimination effect of TN rises with the SRT extension and then slightly tends to decrease. MLVSS/MLSS presents a gradually declining trend with the SRT extension. Sludge volume index (SVI) reduces along with the SRT extension according to the exponential decay tendency, but sludge sedimentation rate (SV30) increases progressively by two step multinomial tendency.