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This paper studied the ultrasonic removal of indigenous blue-green algae taken from Lake Taihu. The results showed that higher ultrasound frequency benefited the removal of indigenous algae. But in consideration of complex condition of the natural lakes and reservoirs such as the lack of powerful electrical supply system, low sound frequency is more suitable. Because of slightly improvement in the algae removal rate constants among the low frequency range (20-100 kHz), 20 kHz is the best ultrasound frequency for indigenous algae removal. Moreover, little change in the microcystins concentration was found with sonication at 20 kHz, 2W for 60s, which was compared with the increased microcystins from 2.67 to 2.851 mg/L after sonication at 1000 kHz, 2W for 60s. the concentration of chlorophyll.

Polyacrylamide-urea-sulfanilamide(PUS) was prepared as a novel heavy metal ions chelator and successfully used to simultaneously remove heavy metals from wastewater effluents. The effects of reaction parameters (sodium hydroxide, material ratio, temperature and contact time) were monitored to specify the best synthesis conditions. PUS was chemically characterized by means of infrared spectroscopy (FTIR). The simultaneous chelation performance of PUS towards selected heavy metals ions, nickel, copper, lead, cadmium and zinc, was discussed, and Ni2+, Cu2+, Pb2+, Zn2+ can be chelated better especially, indicating that the synthesized PUS is a potential remediation material when used for the treatment of wastewater containing metal ions.

Direct preparation of activated carbon (AC) from coal was reported by microwave heating with potassium hydroxide as activation agent. Electrochemical properties of AC electrodes were investigated by cyclic voltammetry, constant current charge–discharge. The results show that functional groups on AC include –C=O, –O–H and –C–O. The micropore volume of AC from different coal totals 48.5–95.6%. The total pore volume of AC from different coal passes through a maximum with the decrease of volatile mater content in coal. The specific surface area and total pore volume of AC from Qing ting coal reach 1874 m2 g-1 and 1.00 cm3 g-1, respectively. The specific capacitance and energy density of AC from higher coal rank is usually bigger than that of AC from lower coal rank.

The aluminum profile can be formed into a complicated part such as 360º abnormity section circle parts that is difficult to be manufactured by other techniques. A new bending method was proposed for bending process. The push-bending principle, deformation procedure, curvature spring-back, section distortion and wrinkling are studied numerically. All cross-sections for the profile are provided a rather homogenous deformation degree. The curvature value of component and the distortion of section keep high consistence in push-bending process. The wrinkling tendency is reduced with increasing relative cross section thickness t/H and die radius R. The numerical model represents the observed response in the laboratory tests fairly well.