The sodium silicate, ferric chloride, ferrous sulfate, sodium chlorate and other common inorganic materials were used to synthesize two new poly silicate iron coagulants: Polysilicate Ferric Chloride (PFSiC) and Po...The sodium silicate, ferric chloride, ferrous sulfate, sodium chlorate and other common inorganic materials were used to synthesize two new poly silicate iron coagulants: Polysilicate Ferric Chloride (PFSiC) and Polymeric Ferric Silicate Sulfate (PFSiS). Their coagulation effect on micro-polluted water was compared with the poly ferric choride (PFC) saled in the market. The results showed that turbidity, organic matter, total phosphorus, total nitrogen removal rate ofPFSiC, PFSiS coagulant were better than PFC on micro-polluted water treatment at the same dosage. The coagulation effect of PFSiC was the best. The surface morphology of three coagulants was observed by scanning electron microscopy (SEM), and the coagulation mechanism was discussed preliminarily.展开更多
Cerium dioxide, CeO2, is a potentially superior material in a myriad of areas, and many methods have been proposed to deposit single crystal CeO2 thin films. A novel fabrication technique utilizing dual plasma generat...Cerium dioxide, CeO2, is a potentially superior material in a myriad of areas, and many methods have been proposed to deposit single crystal CeO2 thin films. A novel fabrication technique utilizing dual plasma generated by metal vacuum arc (MEVVA) and radio frequency (RF) is discussed in this paper. We have recently conducted a systematic investigation to determine the optimal process window to deposit CeO2 thin films'on Si(100) substrates. The X-ray diffraction results show the existence of CeO2(100) in the as-deposited sample.展开更多
Numerical investigations of the 'banding' microstructure formation during solidification of Ti-6Al-4 V alloy in the centrifugal casting are conducted using a multi-scale model, which combines the finite difference m...Numerical investigations of the 'banding' microstructure formation during solidification of Ti-6Al-4 V alloy in the centrifugal casting are conducted using a multi-scale model, which combines the finite difference method (FDM) at the macroscale with a cellular automaton (CA) model at the microscale. The macro model is used to simulate the fluid flow and heat transfer throughout the casting. The micro model is used to predict the nucleation and growth of microstructures. With the proposed model, numerical simulations are performed to study the influences of the nucleation density, mould rotation speed, and casting size upon the 'banding' microstructure formation. It is noted that changing the nucleation density has a minor effect on the microstructure formation. The rotation speed promotes the formation of 'banding' microstructure, which is more noticeable for larger size castings. The 'major mechanism responsible for this 'banding' phenomenon is the spatial variation in cooling rates created by centrifugal force.展开更多
In order to investigate the effect of stripping and catalytic ozone oxidation technology on COD and ammonia nitrogen removal after coagulation and sedimentation, the efficiency of ozone oxidation and catalytic ozone o...In order to investigate the effect of stripping and catalytic ozone oxidation technology on COD and ammonia nitrogen removal after coagulation and sedimentation, the efficiency of ozone oxidation and catalytic ozone oxidation were compared. The experimental results showed that: stripping and catalytic ozone oxidation technology has a significant effect on landfill leachate treatment. The removal rate of the COD and NH3-N can reach 88.60% and 98.00% under the initial concentration of COD and NH3-N were 2053.35 mg/L and l 123. 76 mg/L separately.展开更多
Ultrasonic and jet combined process was studied to remove determined by static experiments, and stability of this combined process algae in lake type raw water. The optimum reaction time was was checked by dynamic exp...Ultrasonic and jet combined process was studied to remove determined by static experiments, and stability of this combined process algae in lake type raw water. The optimum reaction time was was checked by dynamic experiments. The results was showed that ultrasonic/jet combined process has excellent removal efficiency on algae in lake type raw water, and it's a simple operation, and has no secondary pollution. When the pH, temperature, chlorophyll-a(Chl-a) and cell concentration(OD560) of raw water are 7.69, 25.8 ℃, 29.003 mg/m^3 and 0.091, the average removal efficiency on Chl-a and OD560 are 81.60% and 80.22%, respectively, which are stable by this combined process when it is operating in 36 hours, and samples are analyzed each 4 hours.展开更多
文摘The sodium silicate, ferric chloride, ferrous sulfate, sodium chlorate and other common inorganic materials were used to synthesize two new poly silicate iron coagulants: Polysilicate Ferric Chloride (PFSiC) and Polymeric Ferric Silicate Sulfate (PFSiS). Their coagulation effect on micro-polluted water was compared with the poly ferric choride (PFC) saled in the market. The results showed that turbidity, organic matter, total phosphorus, total nitrogen removal rate ofPFSiC, PFSiS coagulant were better than PFC on micro-polluted water treatment at the same dosage. The coagulation effect of PFSiC was the best. The surface morphology of three coagulants was observed by scanning electron microscopy (SEM), and the coagulation mechanism was discussed preliminarily.
基金The work was supported by Hong Kong RGC CERG9040344 and 9040412, RGC / Germany Joint Schemes9050084 and 9050150, and CityU S
文摘Cerium dioxide, CeO2, is a potentially superior material in a myriad of areas, and many methods have been proposed to deposit single crystal CeO2 thin films. A novel fabrication technique utilizing dual plasma generated by metal vacuum arc (MEVVA) and radio frequency (RF) is discussed in this paper. We have recently conducted a systematic investigation to determine the optimal process window to deposit CeO2 thin films'on Si(100) substrates. The X-ray diffraction results show the existence of CeO2(100) in the as-deposited sample.
基金the Science and Technology Department of Hei Longjiang Province (No.GC05A209)the Science and Technology Department of Harbin (No.2005AA5CG046) for financial support.
文摘Numerical investigations of the 'banding' microstructure formation during solidification of Ti-6Al-4 V alloy in the centrifugal casting are conducted using a multi-scale model, which combines the finite difference method (FDM) at the macroscale with a cellular automaton (CA) model at the microscale. The macro model is used to simulate the fluid flow and heat transfer throughout the casting. The micro model is used to predict the nucleation and growth of microstructures. With the proposed model, numerical simulations are performed to study the influences of the nucleation density, mould rotation speed, and casting size upon the 'banding' microstructure formation. It is noted that changing the nucleation density has a minor effect on the microstructure formation. The rotation speed promotes the formation of 'banding' microstructure, which is more noticeable for larger size castings. The 'major mechanism responsible for this 'banding' phenomenon is the spatial variation in cooling rates created by centrifugal force.
文摘In order to investigate the effect of stripping and catalytic ozone oxidation technology on COD and ammonia nitrogen removal after coagulation and sedimentation, the efficiency of ozone oxidation and catalytic ozone oxidation were compared. The experimental results showed that: stripping and catalytic ozone oxidation technology has a significant effect on landfill leachate treatment. The removal rate of the COD and NH3-N can reach 88.60% and 98.00% under the initial concentration of COD and NH3-N were 2053.35 mg/L and l 123. 76 mg/L separately.
文摘Ultrasonic and jet combined process was studied to remove determined by static experiments, and stability of this combined process algae in lake type raw water. The optimum reaction time was was checked by dynamic experiments. The results was showed that ultrasonic/jet combined process has excellent removal efficiency on algae in lake type raw water, and it's a simple operation, and has no secondary pollution. When the pH, temperature, chlorophyll-a(Chl-a) and cell concentration(OD560) of raw water are 7.69, 25.8 ℃, 29.003 mg/m^3 and 0.091, the average removal efficiency on Chl-a and OD560 are 81.60% and 80.22%, respectively, which are stable by this combined process when it is operating in 36 hours, and samples are analyzed each 4 hours.