The effectiveness of a magnetic ion exchange resin （MIEX） for the treatment of Hongze Lake water in China was evaluated, The kinetics of natural organic matter （NOM） removal at various MIEX doses and contact time,...The effectiveness of a magnetic ion exchange resin （MIEX） for the treatment of Hongze Lake water in China was evaluated, The kinetics of natural organic matter （NOM） removal at various MIEX doses and contact time, multiple-loading experiments, impacts of MIEX prior to coagulation on coagulant demands and the effectiveness of combination of MIEX, pre-chlorination and coagulation were investigated. Kinetic experimental results show that more than 80% UV254 and 67% dissolved organic carbon （DOC） from raw water can be removed by the use of MIEX alone. 94% sulfate, 69% nitrate and 98% bromide removals are obtained after the first use of MIEX in multiple-loading experiments. It is suggested that MIEX can be loaded up to 1 250 bed volume （BV, volume ratio of tested water to resin） or more without saturation when regarding organics removal as a target. MIEX can remove organics to a greater extend than coagulation and lower the coagulant demand when combining with coagulation. Chlorination experimental results show that MIEX can remove 57% chlorine demand and 77% trihalomethane formation potential （THMFP） for raw water. Pre-chlorination followed by MIEX and coagulation can give additional organic and THMFP removals. The results suggest that MIEX provides a new method to solve thc problem algae reproduction.展开更多
Salt-induced osmotic pressure has been drawing increasing attention in the field of microalgal biomechanics because it can enhance the lipids accumulation of microalgae.Studies have shown that osmotic stress can affec...Salt-induced osmotic pressure has been drawing increasing attention in the field of microalgal biomechanics because it can enhance the lipids accumulation of microalgae.Studies have shown that osmotic stress can affect the synthesis of phospholipids by activating different phospholipid signaling pathways.However,there is little research about the mechanism of action of osmotic stress in neutral lipids synthesis.In this work,the effects of different salt-induced osmotic pressure on oil synthesis and potential mechanismwere studied.First,effect of various salt4nduced osmotic pressure of 64,112,191,453 and 1304 mOsm/kg on Chlorella pyrenoidosa oil synthesis were studied and optimal salt-induced osmotic pressure of 453 mOsm/kg was acquired.Then the content of key signaling chemicals in the Cyclic Adenosine monophosphate(cAMP)signaling pathway and the key enzyme activities in the lipid synthesis pathway were determined under salt-induced osmotic pressure of 453 mOsm/kg.It was found that the cAMP signaling pathway were up-regulated under salt osmotic pressure conditions of 453 mOsm/kg;in addition,the key enzymes related to lipid synthesis increased,while those related to protein synthesis decreased,enabling the increase of the lipid content.Finally,the effects of inhibitor atropine and promoter IBMX of cAMP signal pathway were also investigated.Results showed that atropine inhibits the cAMP signaling pathway and the lipid contents decreased;in contrast,IBMX activated thecAMP signaling pathway and the lipids content increased.These observations further confirm that salt-induced osmotic pressure had the same function as the signal promoter to regulate lipid synthesis by adjusting cAMP signaling pathway regulating lipid synthesis.This study preliminarily revealed the mechanism that salt-induced osmotic pressure affected lipid synthesis pathway through cAMP signaling pathway to regulate lipid synthesis in microalgae.展开更多
基金Project(2008ZX07421-002) supported by the Key National Science and Technology Project of ChinaProject(50638020) supported by the National Natural Science Foundation of China
文摘The effectiveness of a magnetic ion exchange resin （MIEX） for the treatment of Hongze Lake water in China was evaluated, The kinetics of natural organic matter （NOM） removal at various MIEX doses and contact time, multiple-loading experiments, impacts of MIEX prior to coagulation on coagulant demands and the effectiveness of combination of MIEX, pre-chlorination and coagulation were investigated. Kinetic experimental results show that more than 80% UV254 and 67% dissolved organic carbon （DOC） from raw water can be removed by the use of MIEX alone. 94% sulfate, 69% nitrate and 98% bromide removals are obtained after the first use of MIEX in multiple-loading experiments. It is suggested that MIEX can be loaded up to 1 250 bed volume （BV, volume ratio of tested water to resin） or more without saturation when regarding organics removal as a target. MIEX can remove organics to a greater extend than coagulation and lower the coagulant demand when combining with coagulation. Chlorination experimental results show that MIEX can remove 57% chlorine demand and 77% trihalomethane formation potential （THMFP） for raw water. Pre-chlorination followed by MIEX and coagulation can give additional organic and THMFP removals. The results suggest that MIEX provides a new method to solve thc problem algae reproduction.
基金supported by the National Natural Science Foundation of China ( 51376200)the social livelihood projects of Chongqing City ( 10 cstc2018jscx-msybX0227)
文摘Salt-induced osmotic pressure has been drawing increasing attention in the field of microalgal biomechanics because it can enhance the lipids accumulation of microalgae.Studies have shown that osmotic stress can affect the synthesis of phospholipids by activating different phospholipid signaling pathways.However,there is little research about the mechanism of action of osmotic stress in neutral lipids synthesis.In this work,the effects of different salt-induced osmotic pressure on oil synthesis and potential mechanismwere studied.First,effect of various salt4nduced osmotic pressure of 64,112,191,453 and 1304 mOsm/kg on Chlorella pyrenoidosa oil synthesis were studied and optimal salt-induced osmotic pressure of 453 mOsm/kg was acquired.Then the content of key signaling chemicals in the Cyclic Adenosine monophosphate(cAMP)signaling pathway and the key enzyme activities in the lipid synthesis pathway were determined under salt-induced osmotic pressure of 453 mOsm/kg.It was found that the cAMP signaling pathway were up-regulated under salt osmotic pressure conditions of 453 mOsm/kg;in addition,the key enzymes related to lipid synthesis increased,while those related to protein synthesis decreased,enabling the increase of the lipid content.Finally,the effects of inhibitor atropine and promoter IBMX of cAMP signal pathway were also investigated.Results showed that atropine inhibits the cAMP signaling pathway and the lipid contents decreased;in contrast,IBMX activated thecAMP signaling pathway and the lipids content increased.These observations further confirm that salt-induced osmotic pressure had the same function as the signal promoter to regulate lipid synthesis by adjusting cAMP signaling pathway regulating lipid synthesis.This study preliminarily revealed the mechanism that salt-induced osmotic pressure affected lipid synthesis pathway through cAMP signaling pathway to regulate lipid synthesis in microalgae.
