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Microwave bubble plasma in water is a novel plasma applicable to the processing of materials in liquid. An electromagnetic simulation of slot excitation of microwaves reveals that the electric field at a slot antenna is significantly influenced by the size of the bubble existing in front of the antenna. To improve the power efficiency and the plasma stability, a bubble control plate is installed adjacent to the antenna, the effect of which on the electric field enhancement is confirmed in the simulation. Furthermore, three slot antennas are newly developed. According to these modifications of the microwave excitation system, a dramatic increase in the decomposition efficiency of an organic solute by a factor of 20 is found in the experiment.

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The local atomic structure in the amorphous Al x ͑Cu 0.4 Y 0.6 ͒ 100Ϫx and Mg x ͑Cu 0.4 Y 0.6 ͒ 100Ϫx ͑0рxр85͒ alloys was determined by neutron-diffraction experiments. The electronic structure near the Fermi level was determined using the same samples by means of x-ray photoemission spectroscopy and soft x-ray spectroscopy. Both sets of data are combined to determine self-consistently and uniquely the local atomic structure in both Al-and Mg-based amorphous alloys. The bonding nature and resulting atomic environment are found to depend significantly on whether the third element is Al or Mg. Based on the atomic and electronic structures thus derived, we could interpret the Al or Mg concentration dependence of the crystallization temperature, electronic specific-heat coefficient, and also that of the resistivity value of 300 K. The origin of the appearance of a positive Hall coefficient observed in the Al-based amorphous alloys but not in the Mg-based amorphous alloys is also briefly discussed.

The in situ binding of tin oxide (SnO 2 ) nanoparticles (SNp) and graphene nanosheets (GNs) that synthesized simultaneously in single-step atmospheric-pressure processing was achieved at a low temperature by employing in-liquid plasma in a solution of tin chloride (SnCl 2 •2H 2 O) in ethanol as the only precursor. Transmission electron microscopy, Raman analysis, and X-ray diffraction revealed the composite (SNp/GNs) synthesis with SNp of sizes 2−3 nm, which were distributed uniformly and attached to both sides of the GNs. The SNp/GNs composite synthesis was provided by the simple, low-cost, singleprocessing method of the in-liquid plasma for future gas-sensing and lithium-ion battery applications.

BackgroundArsenic exposure induces overproduction of reactive nitrogen species (RNS) in brain tissue and results in nucleic acid damage to the nerve cells. The 8-nitroguanine is one of the major products formed by the reaction of guanine, and ONOO-, and has been used as a popular biomarker of nucleic acid damage due to RNS attacking. In the present study, we examined whether the administration of taurine can protect against nucleic acid damage of brain neurons by arsenic-induced RNS.Materials and methodsSixty mice (30 male and 30 female) weighing 19.5 ± 1.5 g were divided into 3 groups: (1) control group, (2) experimental group that received arsenic (As2O3), and (3) antagonistic group that received taurine with arsenic. Arsenic was administered for 60 days. 8-Nitroguanine expressions in brain neurons of mice were examined by the immunohistochemical method. Histopathological changes in brain tissues of mice were observed under light microscope and the immunohistochemistry method was used to investigate 8-nitroguanine expressions in cerebrum and cerebellum of mice.ResultsIn the control group, no abnormal histopathological changes were observed in brain tissue of the mice. In brain tissue of the mice exposed to arsenic, histopathological results showed swells, evident vacuolar degeneration in cytoplasm, karyorrhexis and karyolysis. Relatively light pathological changes were observed in brain of the mice co-administered arsenic and taurine. Little or no expression of 8-nitroguanine in brain tissue was observed in controls. However, intensive expression of 8-nitroguanine was found in brain tissue of mice exposed to arsenic and it was mainly distributed in nucleus neighbouring the nuclear membrane, but a little in cytoplasm. A weak expression of 8-nitroguanine was observed in brain cells of mice co-administered arsenic and taurine.ConclusionsThe brain neurons may be the major target cells of arsenic neurotoxicity. Co-administration of arsenic and taurine can alleviate DNA damage of brain neurons caused by arsenic through the RNS signal pathway.

The tin oxide (SnO 2 )-graphene composite was synthesized by the in-liquid plasma method using SnO 2 nanoparticles (average diameter ~30 nm) dispersed ethanol as a precursor without providing external heat. As observed from scanning electron microscopy (SEM) and transmission electron microscopy (TEM), the SnO 2 nanoparticles were distributed uniformly on flaky graphene sheets. The formation of SnO 2 and high crystalline graphene was supported by the Raman analysis and x-ray diffraction (XRD) studies. A facile, low-cost method operating at atmospheric pressure based on the in-liquid plasma technology can be utilized to fabricate SnO 2 -graphene composite using minimum precursors for future applications such as gas sensing devices and fuel cells.

Amorphous carbon (a-C) films are deposited using a radical-injection plasma-enhanced chemical vapor deposition (RI-PECVD) system employing a mixture of H 2 and CH 4 gases. Variations in the structural and electronic properties of the resulting films with changes in the residence times of radical species and molecules are investigated by varying the total gas flow rate from 50 to 400 sccm. With decreasing residence time, the deposition rate is found to gradually increase, reaching a maximum value at a residence time of 6 ms, after which a decrease was observed. Optical emission spectra showed that the relative intensity of the CH emission increased with decreasing residence time. These results indicate a change in the dominant radical species resulting from suppression of the dissociation of radicals and molecules. Increasing amorphization and an obvious increase in the Tauc gap from 0.6 to 0.9 eV are found with decreasing residence time, while there is little change in the hydrogen content of the films. From these data, it is evident that control over the structural properties and optical bandgap of a-C films can be realized by optimizing the distribution of radical species.