Abstract: The present invention provides a method for detecting biochemical oxygen demand. Active sludge, surface water, domestic waste water, or industrial waste water comprising microorganism is taken as a water sample with microorganism in the method provided by the present invention. The water sample with microorganism is cultivated to obtain a microorganism film. The blank water sample and the target water sample are made to pass through the microorganism film respectively. The dissolved oxygen reduction current values of the blank water sample and the target water sample are detected. The difference value between the dissolved oxygen reduction current value of the target water sample and that of the blank water sample is obtained. On the basis of the difference value and the predetermined standard curve, the biochemical oxygen demand of the target water sample is acquired.

Abstract: The present invention provides a method for detecting biochemical oxygen demand. Active sludge, surface water, domestic waste water, or industrial waste water comprising microorganism is taken as a water sample with microorganism in the method provided by the present invention. The water sample with microorganism is cultivated to obtain a microorganism film. The blank water sample and the target water sample are made to pass through the microorganism film respectively. The dissolved oxygen reduction current values of the blank water sample and the target water sample are detected. The difference value between the dissolved oxygen reduction current value of the target water sample and that of the blank water sample is obtained. On the basis of the difference value and the predetermined standard curve, the biochemical oxygen demand of the target water sample is acquired.

Abstract: The present invention provides a method for preparation of poly(o-phenylenediamine) nano-belt comprising mixing aqueous solutions of o-phenylenediamine and of oxidant in a mole ratio of 1:0.1–1 under stirring; standing for 0.5–2 hrs at room temperature; and obtaining poly(o-phenylenediamine) nano-belt. The method is suitable for large-scale production. In the absence of template and surfactant, aqueous solutions of o-phenylenediamine and of oxidant are mixed in a specified mole ratio and thus obtain a poly(o-phenylenediamine) nano-belt with length of several hundred micrometers, width of several hundred nanometers and thickness of tens nanometers. The method is simple, quick and suitable for large-scale manufacture. The poly(o-phenylenediamine) nano-belt thus prepared possesses excellent semiconductor properties and is one of the most promising conductive polymer materials.

Abstract: The present invention provides a method for preparation of poly(o-phenylenediamine) nano-belt comprising mixing aqueous solutions of o-phenylenediamine and of oxidant in a mole ratio of 1:0.1-1 under stirring; standing for 0.5-2 hrs at room temperature; and obtaining poly(o-phenylenediamine) nano-belt. The method is suitable for large-scale production. In the absence of template and surfactant, aqueous solutions of o-phenylenediamine and of oxidant are mixed in a specified mole ratio and thus obtain a poly(o-phenylenediamine) nano-belt with length of several hundred micrometers, width of several hundred nanometers and thickness of tens nanometers. The method is simple, quick and suitable for large-scale manufacture. The poly(o-phenylenediamine) nano-belt thus prepared possesses excellent semiconductor properties and is one of the most promising conductive polymer materials.