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In this article, the sludge-based activated carbon was prepared by the sewage sludge from the municipal wastewater treatment plants with ZnCl2 as the activator. The concentration of the activator was 30% and the pyrolysis temperature and duration were 500℃ and 1 hour, respectively. The yield of sludge-based activated carbon was 30.14% with 4.66% ash. Under the best preparation condition, carbon content would be highest and the pore structure would be clear. The sludge-based activated carbon was mainly composed of mesopores. The main adsorption peaks of the sludge-based activated carbon were C-O-C (1078.3 cm-1), C=C（1568.7 cm-1）and –OH（3190.9 cm-1）groups.

A new strategy using an amperometric biosensor with Escherichia coli (E. coli) that provides a rapid toxicity determination of chemical compounds is described. The CellSense biosensor system comprises a biological component immobilized in intimate contact with a transducer which converts the biochemical signal into a quantifiable electrical signal. Toxicity assessment of heavy metals using E.coli biosensors could be finished within 30min and the 50% effective concentrations (EC50) values of four heavy metals were determined. The results shows that inhibitory effects of four heavy metals to E.coli can be ranked in a decreasing order of Hg2+>Cu2+>Zn2+>Ni2+, which accords to the results of conventional bacterial counting method. The toxicity test of organic compounds by using CellSense biosensor was also demonstrated. The CellSense biosensor with E.coli shows a good, reproducible behavior and can be used for reproducible measurements.

Nano-hydroxyapatite/polyamide66/chitosan composite (n-HA/PA66/CS) was prepared by a co-precipitation method and porous scaffolds from n-HA/PA66/CS composite were prepared by means of porogen–leaching method and were characterized by SEM, IR, XRD and universal mechanical testing machine. IR and XRD analyses showed that some chemical bonds existed between n-HA and polymers. Furthermore, macroporous structure of the scaffolds and mechanical strength were tested with a changed ratio of porogens (PVP/NaCl). When the ratio of PVP and NaCl is1: 6, the scaffold processed highly porosity and the pores were interconnected. The compressive strength of the scaffold, can meet the requirement of tissue regeneration.

The aim of this study is to explore the effects of quenching and milling processing on setting property of calcium phosphate cement (CPC). For this purpose, non-quenched α-tricalcium phosphate (α-TCP) and quenched α-TCP were synthesized and their corresponding cement systems were prepared. The particle size of α-TCP powder was introduced as a variable. Then, setting properties of these CPC systems were estimated. By a comparison between non-quenched CPC and the quenched one, it is found that milling processing mainly influences the initial setting stage by decreasing reactant particle size whereas the quenching treatment affects the final setting stage by changing α-TCP content, which supports that CPC setting initially depends on the surface area of reactants and subsequently on the diffusion through the hydrated layer formed around the reactants.

Nano-hydroxyapatite/polyamide66/chitosan composite (n-HA/PA66/CS) was prepared by a co-precipitation method, and was characterized by TG/DTG, TEM, IR, XRD and Universal mechanical testing machine. TEM test showed that some rod like crystals were formed and distributed uniformly into polymer matrix, with a size of about Φ30nm×80nm. IR and XRD analysis showed that some chemical bonds and electrostatic interaction existed between n-HA and polymers. TG/DTG curves indicated that the composites possessed a talent of high heat-resistance. The compressive strength of composite changed with different content of three compounds, the maximum compressive strength of composite (70MPa) could be acquired.