The growth in technology, digital electronics and wireless communications has made sensor networks a reality. The low cost, low power but multifunctional sensor nodes communicate with other nodes and need to be energy efficient in order to save battery power. This paper deals with the problem of sensor network lifetime optimization. By setting up data flows among sensor nodes as optimization va...

A charge-transfer complex was modified on the graphite paste electrode for making a sensitive dissolved oxygen sensor. It was composed of copper with two ligands of phenanthroline and 1,2-dicyano-1,2-dithiolethane. Because of the low redox potential of the core ion and the pull and repulsive effect from the ligands, the redox of modified complex toke place under lower potential and it could sel...

Choline can be covalently grafted on glassy carbon electrodes using cyclic voltammetric method, forming a stable cationic monolayer-modified electrode (Ch/GCE). Keggin-type molybdophosphate anions, alpha-PMo(12)O(40)(3-), then were self-assembled on the Ch/GCE through electrostatic interactions for fabrication of an electrochemical sensor, which is denoted as alpha-PMo(12)/Ch/GCE. This two-laye...

In the present paper, electrochemical methods were used to investigate the behavior of ascorbic acid at a carbon paste electrode modified with 2,2'-((1E)-(1,2 phenylenebis(azanylylidene)) bis(methanylylidene))bis(benzene-1,4-diol) (PBD) and oxidized multiwall carbon nanotubes. The modified carbon paste electrode showed high electrocatalytic activity toward ascorbic acid; the current was enhance...

This paper is concerned with a networked estimation problem in which sensor data are transmitted over the network. In the event-based sampling scheme known as level-crossing or send-on-delta (SOD), sensor data are transmitted to the estimator node if the difference between the current sensor value and the last transmitted one is greater than a given threshold. Event-based sampling has been show...

Clomipramine hydrochloride, active component of an antidepressant drug, was determined in the pharmaceutical formulation by two kinds of potentiometric sensor; a PVC membrane sensor and a carbon paste electrode modified by MWCNTs and ionic liquid. Both sensors were corporated with clomipramine-tetraphenylborate ion-pair complex and they respond based on ion exchange mechanism. The best PVC memb...

The magnetic shape-memory alloy Ni-Mn-Ga shows, in monocrystalline form, a reversible magnetic-field-induced strain (MFIS) up to 10%. This strain, which is produced by twin boundaries moving solely by internal stresses generated by magnetic anisotropy energy, can be used in actuators, sensors and energy-harvesting devices. Compared with monocrystalline Ni-Mn-Ga, fine-grained Ni-Mn-Ga is much ea...

Energy efficiency operations are essential in increasing the lifetime of Wireless Sensor Networks. Clustering sensor nodes is an energy saving based interesting technique for achieving these goals. The main challenge in wireless sensor network is to optimize energy consumption when collecting data from sensor nodes. Efficiently collecting the data in wireless sensor networks plays a key role in...

We report a novel and sensitive amperometric sensor for chlorpromazine (CPZ) based on reduced graphene oxide (RGO) and polydopamine (PDA) composite modified glassy carbon electrode. The RGO@PDA composite was prepared by electrochemical reduction of graphene oxide (GO) with PDA. The RGO@PDA composite modified electrode shows an excellent electro-oxidation behavior to CPZ when compared with other...