The electrochemical behavior of BH4- on Cu electrode in 1M NaOH was investigated by cyclic voltammetry(CV) in the potential range of -1.2V to 0.4V versus Hg/HgO. The CV results show that Cu electrode has obvious catalytic activities to the BH4- hydrolysis which belongs to ‘catalytic’ electrode materials. The BH4- electro-oxidation process on Cu is complex and it could associate with the BH4- hydrolysis reaction, followed by oxidation of the intermediate H, then, the intermediate product (e.g. BH3OH−) oxidized, and direct oxidation of BH4- at more positive potentials.

It is not accurate incorporating the demagnetizing field by the average demagnetizing factor due to the time variations of the permeability and the dependence of the demagnetization field on the permeability of the sample material. Especially when the magnetic field changes with the position greatly, the local demagnetizing tensor can't be simplified as a number D, thus the internal field H can't be described by demagnetization coefficient D. Although the transient magnetic simulation using the finite-element method can give a correct result, the computation time is relatively too long. Especially for voltage source excitation, a number of trial transient magnetic simulations have to be performed to find the suitable number of winding, the voltage supply, and the excitation frequency. To reduce the optimization time, a method was proposed in this work. With our method only one transient magnetic simulation with current source excitation using the finite-element method was needed. Optimization can be performed using HSPICE. Experiment results confirmed the validity of our method.

Addressing drawbacks of analog components and questions of multi-channel fluxgate signal operation, a FPGA (Field Programmable Gate Array) based signal processing system is designed. Three copies of sub modules compose the whole system, each of which exclusively processes one of three outputs of the fluxgate sensor. A “Phase-Sensitive-Rectification & Low-Pass-Filtering” circuit structure is employed in the processing module, through which the fluxgate signal harmonics are extracted and converted into direct quantities according to detected magnetic intensities. Firstly designed in HDL (Hardware Description Language), afterward configurated in a FPGA chip, finally tested by processing outputs of a fluxgate sensor probe in real-time, the functionality of the designed system is verified. With inherent advantages, this FPGA based design is much reliable over temperature; by processing signals not time-sharingly but synchronously, its working speed is excellently high.

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A kind of double-layer Si-based microcantilever was fabricated using standard integrated circuit and micro-mechanical machining technology. It was thermally-excited and the signal was detected based on piezoresistance effect of semiconductors. Taking the advantage of FPGA, the digital closed-loop system on silicon resonant microcantilever was implemented. On this basis, the resonant characteristics like amplitude of output signal, the resonant frequency shift, the frequency stability and the quality factor of this kind of microcantilever were studied through theoretical analysis and experiment. This paper focus on the dependence of amplitude of output signal on the exciting power, bias voltage as well as the dependence of resonant frequency shift of output signal on the exciting voltage, bias voltage. Analysis about the result of the experiment was given, which showed that this silicon microcantilever is suitable for resonant microsensor, and provided some advices for the optimum design of the system. It laid the foundation for the development of a new resonant structure of silicon micro-cantilever sensors.