The low-power radio is the same as that used on the Berkeley MICA2 mote, making BTnode a twin of MICA2 [20].Table 1.Characteristic ubiquitous sensor network platforms.As shown in Table 1, among the site all these platforms the smart sensor in EMMNet provides the longest communication distance. It is thus suitable for applications in complex urban environments, Inhibitors,Modulators,Libraries where electricity meters in tall buildings are often installed inside metal chests and separated by concrete walls. The external memory space of the data collector in EMMNet is 4 MB and that of data concentrators is 8 MB. The external memory space of EMMNet is large, because collectors and Inhibitors,Modulators,Libraries concentrators need to Inhibitors,Modulators,Libraries record the data and parameters from hundreds of electricity meters. The cost of EMMNet is also lower than that of any other platform listed in Table 1.

A dynamic power-management Inhibitors,Modulators,Libraries technique is an additonal feature of
Nitrite is a typical inorganic pollutant in environmental, food, industrial and physiological systems [1�C3], therefore, various methods for detection and determination of nitrite have been reported, involving spectroscopic, chromatographic, electrochemical detection methods, etc. [3�C5]. Although spectroscopic and chromatographic methods are accurate and reliable, they require bulky, delicate and expensive equipment which is not suitable for in situ applications. Biosensor-based methods have been another option for this purpose, for example, nitrate reductase (NiR)-based optical [6�C8] and electrochemical [9�C19] biosensors have been reported.

In electrochemical detection, although direct electron transfers (DET) between electrode and NiRs were seldom reported [11,20,21], most of the reported electrochemical nitrite biosensors were based on co-immobilization of NiR and respective mediators. There have been various reported co-immobilization Drug_discovery methods for NiR and mediators, such as electropolymerization [13,15], dialysis membrane [12,14] or polymer membrane covering [17], polymer entrapment [11], covalent binding on self-assembled monolayer (SAM) surface [16], electrostatic interaction [18], adsorption and following cross-linking [19], etc., each of which have their respective merits and defects. In this study, a synthesized polymeric CHIT-V mediator and NiR were co-immobilized by drop-coating of HPU, due to its simplicity and effectiveness [22].

Recently, studies on structures and catalytic mechanisms of NiRs have been actively carried out [23�C33]. NiRs can be classified into copper-based NiRs and iron-based NiRs. The iron-based NiRs include cc-NiRs which contain several c-type hemes or siroheme Gemcitabine HCl catalyzing 6-electron reduction of nitrite to ammonia and cytochrome cd1 NiR catalyzing 1-electron reduction of nitrite to nitric oxide. The Cu-NiRs are also known to catalyze 1-electron reduction reactions [12,26,29,30].