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A simple and sensitive high performance liquid chromatography method with UV detection was described for the determination of colchicine (COL) in mouse plasma. After single-step deproteinization by acetonitrile using berberine hydrochloride as an internal standard (I.S.), solutes were separated on a Diamonsil C 18 column (250 mm×4.6 mm I.D., 5 mm particle size)(Dikma), using acetonitrile 0.15％ phosphoric acid solution (27：73, v/v) as mobile phase (‰ow-rate 1.0 ml/min); wavelength of the UV detector was set at 350 nm. No interference from any endogenous substances was observed during the elution of COL and internal standard (I.S., berberine hydrochloride). The retention times for COL and I.S. were 11.23 min and 8.82 min, respectively. The limit of quantiˆcation was evaluated to be 1.5 ng/ ml and the limit of detection was 0.5 ng/ml. The method was used in the study of pharmacokinetics of COL after intravenous injection (i.v.) and intraperitoneal injection (i.p.). The result indicated that COL disappears from the plasma according to a three compartment open model.

The resistive switching variability and reliability degradation are the two major challenges that hinder the high-volume production of the Resistive Random Access Memory (RRAM) devices. In this work, a 3D electrode structure engineering method is proposed. The geometric parameters defined as electrode angle (EA), electrodes spacing (ES) and electrode trench depth (ETD) associated with the double wedge-like electrodes of the filament-type RRAM devices are studied for the first time. Our experimental results show that apart from the resistive switching uniformity, the reliability performance such as cycling endurance and data retention are significantly improved for the device with small EA (90 •), narrow ES (440 nm) and deep ETD (90 nm) owing to the electric field confinement and enhancement. Thus, this new approach can be served as a guideline for the design and optimization of the filament-type RRAM devices. INDEX TERMS Electrode structure engineering, resistive switching uniformity, RRAM device reliability.

Since Particle Reinforced Metal Matrix Composites (PRMMC) normally applied Al2O3, SiC particle and other hard material as reinforce item, traditional manufacturing processes are hard to machine PRMMC with high efficiency and low tool cost. This paper presents an electrochemical mechanical (ECMM) hybrid polishing procedure for PRMMC, and the influences of parameters such as work voltage, grinding area proportion, the formula and concentration of electrolyte has been investigated. Through a hybrid polishing compound with a no Z direction feed pure mechanical grinding progress in Vx opposite direction, Ra around 0.5um PRMMC surface can be achieved.

A micro Electrochemical Machining (ECM) system has been developed, and macro/micro complex feed mechanism has been presented in order to achieve high-resolution. A nanosecond pulse power supply for micro-ECM has been developed, and the minimum pulse width can reach 50 ns. Complementary chopper circuit has been designed to avoid waveform distortion, which can achieve higher pulse frequency. A series of ECM experiments using the machining system have been carried out, and results of tests have proved that high-resolution spindle, and high frequency, short pulse width power supply help to achieve better quality surface, higher machining accuracy.