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We simultaneously measured the diffuse reflectance spectra and transmittance spectra of in vitro rat cerebral cortical tissue slices perfused with artificial cerebrospinal fluid (aCSF) in the wavelength range from 500 to 900 nm. An ischemia-like condition in the cortical tissue was induced by oxygen/glucose deprivation (OGD) of the aCSF. Diffuse reflectance and transmittance of the cortical slices were decreased and increased, respectively, during OGD. Spectral data of reduced scattering coefficients and absorption coefficients were estimated by the inverse Monte Carlo simulation for light transport in tissue. As with OGD, significant decrease of the reduced scattering coefficients and alteration of the absorption coefficient spectrum were observed over the measured wavelength range. The mean maximum amplitudes of change in the absorption coefficient at 520, 550, 605, and 830 nm were 0.33 [+ or -] 0.14, 0.30 [+ or -] 0.12, 0.30 [+ or -] 0.14, and -0.04 [+ or -] 0.16, respectively, whereas those in the reduced scattering coefficient at 520, 550, 605, and 830 nm were -0.37 [+ or -] 0.08, -0.38 [+ or -] 0.08, -0.38 [+ or -] 0.08, and -0.39 [+ or -] 0.08. Variations in the reduced scattering coefficients implied cell deformation mainly due to cell swelling, whereas those in the absorption spectra indicated reductions in heine [aa.sub.3] and CuA in cytochrome c oxidase and cytochrome c. [c] 2010 Optical Society of America OCIS codes: 170.0170, 170.3660, 170.6510, 170.6935.

Numerical and experimental analyses are conducted on a nanosecond pulse dielectric barrier discharge-induced nonthermal plasma (NTP) for pollution control. In the numerical analysis, a commercial simulation software, CFD-ACE+ solver, is used. The result indicates that a streamer progressing from the positive electrode to the grounded one is well simulated. At the end of the pulse, the electron temperature and electron number density in the coaxial-type plasma reactor finally reach approximately 1.7 eV and [10.sup.15] [m.sup.-3], respectively. The radial electric field is almost constant in the plasma region. During the single pulse, the peak concentration of ozone is approximately 40 ppm near the surface of the glass barrier. Next, an experimental analysis on the optical emission spectra of the NTP is carried out. In the result, the second positive bands spectra of [N.sup.2] are observed. The evaluated electron temperature is almost constant (approximately 1.8 eV), irrespective of frequency, discharge power, and radial position. This value and tendency agree well with the numerical results. Index Terms--Dielectric barrier discharge, electron temperature, emission spectroscopy, nonthermal plasma (NTP), numerical analysis, pollution control, pulse corona discharge, streamer.

Over the years, we have investigated particulate matter (PM) and N[O.sub.x] reduction using nonthermal plasma-chemical hybrid processes without using catalysts. Among nonthermal plasma hybrid processes, the ozonizer combined with the chemical hybrid reactor was investigated using a 479 cc (5.5 kW) power generation diesel engine. The PM deposited on the diesel particulate filter can be incinerated by ozone and N[O.sub.2] in a wide range of flue gas temperature. The NO was oxidized to form N[O.sub.2] by ozone, and N[O.sub.2] was reduced by the 3% [Na.sub.2]S[O.sub.3] chemical reactor. As the results, PM deposited on both metal and ceramic filters were successfully removed even at ambient temperature. The rate of PM incineration depends on the amount of ozone injected and was significantly higher than the rate of PM generation. Using 2.4% ozone concentration with a flow rate of 10 L/min, 82% of NO having 720 L/min was oxidized to N[O.sub.2], and 78% of N[O.sub.x] was removed as a chemical scrubber. However, N[O.sub.x] removal was deteriorated about 10% after 1-h operation. This was attributed to [Na.sub.2]S[O.sub.3] oxidation by air, which was evidenced by the reduction of pH in the chemical reactor. Index Terms--Diesel particulate filter (DPF), N[O.sub.x], nonthermal plasma, particulate matter (PM), plasma-chemical hybrid processes.

In this paper, the results of two experiments are reported. First, the performances of various types of nonthermal plasma reactors for N[O.sub.x] reduction were compared. It was shown that the surface-discharge reactors have as high N[O.sub.x] reduction capabilities as pulse-powered wire-cylinder reactors. Second, N[O.sub.x] treatment using the surface-discharge reactor with a NO-adsorbent zeolite 13X was performed. Thermal desorption was employed for the regeneration of the zeolite. The N[O.sub.x] of 350 ppm was kept lower than 18 ppm for at least 11 h, whereas it degraded to 75 ppm in the absence of the regeneration. The result suggested the possibility of an aftertreatment system that employed thermal desorption by utilizing the waste heat of diesel engine exhaust and N[O.sub.x] reduction by using a surface-discharge reactor. Index Terms--Nonthermal plasma (NTP), N[O.sub.x], packed-bed, surface discharge, thermal desorption, zeolite, 13X.

An effective NOx-reduction aftertreatment system for a marine diesel engine that employs combined nonthermal plasma (NTP) and adsorption is investigated. The system can also treat particulate matter (PM) that employs a diesel particulate filter (DPF) and its regeneration by NTP-induced ozone. The effect of the combined reduction of accumulated PM and NOx is studied. The marine diesel engine of interest provides an output power of 1 MW at 100% of the engine load. The NOx reduction is composed of repeated adsorption and desorption flow processes using NTP combined with NOx adsorbents. With a view toward practical use, experiments on a higher number of cycles are carried out. The amount of adsorbents is 105 kg, which is greater than that in the authors’ previous study. As a result, NOx reduction efficiency by NTP is higher than in the previous study and is greater at higher amounts of adsorbents owing to higher NOx desorption. Furthermore, DPF regeneration with plasma-induced O3 injection is achieved simultaneously. This aftertreatment system demonstrates an excellent energy efficiency of 114 g(NO2)/kWh. The present aftertreatment can generate a synergistic effect of PM and NOx reduction. [ABSTRACT FROM AUTHOR]