A Novel Thin-Layer Flow Cell Sensor System Based on BDD Electrode for Heavy Metal Ion Detection.

An electrochemical sensor based on a thin-layer flow cell and a boron-doped diamond (BDD) working electrode was fabricated for heavy metal ions determination using anodic stripping voltammetry. Furthermore, a fluidic automatic detection system was developed. With the wide potential window of the BDD electrode, Zn with high negative stripping potential was detected by this system.

Pattern formation based on the triple-layer coupling mechanism.

We report on the first investigation of the triple-layer coupling pattern formation in a dielectric barrier discharge system. The pattern basically consists of one discharge subpattern ignited in the gas gap and two surface-charge subpatterns deposited on the dielectric surfaces. The coupling of the three subpatterns (layers) is presented by analyzing the time-resolved discharge sequence of a white-eye hexagonal super lattice pattern (WEHSP).

[Measurement of molecular vibrational temperature of the white-eye pattern in dielectric barrier discharge].

The white-eye pattern, whose cell is composed of a bright dot surrounded by a closed hexagon, was observed in air/ argon dielectric barrier discharge. It was found that the center dot, the vertex of hexagon and the center of hexagon side in a cell have different brightness. By using optical emission spectra, the vibrational temperature in the center dot, the vertex of hexagon and the center of hexagon side was measured, respectively.

[Measurement of plasma parameters in cluster hexagon pattern discharge by optical emission spectrum].

The cluster hexagon pattern was obtained in a dielectric barrier discharge in air/argon for the first time. Three plasma parameters, i. e.

Formation of spiral patterns in dielectric-barrier discharge investigated by an intensified-charge coupled device.

The formation of the spiral patterns in dielectric-barrier discharge is investigated through instantaneous pictures at successive driving half cycles taken by an intensified-charge coupled device (ICCD). The filaments discretely distributed in each instantaneous picture corresponding to one discharge pulse indicate that they are the basic unit of the spiral patterns. An individual filament can undergo two movement states within continuous discharges: pinning at the same locations and shifting along the arm with a small displacement (less than the filament radius), which results in the formation of smooth arms.

Motion of rotating pairs in a hexagonal superlattice pattern within dielectric barrier discharge.

Stochastic rotation of rotating pairs in a hexagonal superlattice pattern is observed in a dielectric barrier discharge system. It is found that the pairs rotate with orientation and diameter randomly changing by observing a series of frames recorded by a high speed video camera. Frames recorded by a high speed framing camera with an exposure time corresponding to current pulse phases in one half cycle of the applied voltage show that one rotating spot, six small spots, and another rotating spot in one cell discharge successively.

[Spectra line profile and vibrational temperature of bright dot and dark dot discharge in a dielectric barrier discharge].

The emission spectrum line shift and vibrational temperature of the bright dot and dark dot discharges, which are observed in the argon and air dielectric barrier discharge at high temperature for the first time were measured and compared. The line shift of the spectral line of the Ar I (2P2-->1S5) is measured and the vibrational temperature was calculated using by the emission spectral lines of the N2 second positive band system (C3Pi(u)-->B3Pi(g)). The results show that the spectrum line shift of the bright dot discharge channel is larger than that of the dark dot channel, which indicates that the former has higher electron density compared to the latter, and the vibrational temperature of the dark dot discharge channel is higher than that of the bright dot discharge channel.

[Study on plasma parameters in diffuse discharge with semispherical electrod by optical emission spectrum].

The diffuse discharge plasma in air was observed in a dielectric barrier discharge with two semispherical water electrodes. The variations of vibration temperature, rotation temperature, and average electron energy as the function of the applied voltage were studied by emission spectroscopy. The vibration temperature and the rotation temperature were calculated through the second positive band system (C3Pi(u)-->B3Pi(g)) of N2+ and the first negative band system (B2 Sigma(u+)-->Chi2Sigma(g+)) of N(2+) respectively.