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The integrated microwave with Mn/γ-Al2O3 and ozone was employed to oxidize elemental mercury (Hg0) in simulated flue gas. Hg0 oxidation efficiency in the integrated system attained 92.2%. Mn/γ-Al2O3 catalyst was characterized by XRD, XPS, FT-IR, SEM. XPS spectra indicate the formation of a stable mercuric oxide species (HgO) from mercury oxidation. Ozone molecules in air could enhance free radical formation. Hg0 was oxidized to HgO in the presence of ozone and free radical. The coupling role between ozone and radical on mercury oxidation was formed. Microwave catalytic oxidation of elemental mercury reaction with the Mn/γ-Al2O3 catalyst follows Langmuir–Hinshelwood kinetics.

The integrated microwave with Mn/zeolite and ozone (MCO) and combined microwave with Mn/zeolite (MC) was employed to oxidize elemental mercury (Hg0) in simulated flue gas. The results show that mercury removal efficiency attained 35.3% in the MC, over 92% of Hg0 removal efficiency could be obtained in the MCO. The optimal microwave power and empty bed residence time (EBRT) in the microwave plasma catalytic oxidation were 264 W and 0.41 s, respectively. The effect of Hg0 oxidation in the MCO was much higher than that in the MC. Microwave accentuated catalytic oxidation of mercury, and increased mercury removal efficiency. The additional use of ozone to the microwave–catalysis over Mn/zeolite led to the enhancement of mercury oxidation. Mn/zeolite catalyst was characterized by X–ray diffraction (XRD), X–ray photoelectron spectroscopy (XPS), Fourier transform infrared spectra (FT–IR), scanning electron microscopy (SEM) and the Brunauer Emmett Teller (BET) method. Microwave catalytic mercury over Mn/zeolite was dominated by a free radical oxidation route. Ozone molecules in air could enhance free radical formation. The coupling role between ozone and radicals on mercury oxidation in the MCO was formed. The MCO appears to be a promising method for emission control of elemental mercury.

Newly acquired fingerprint images have a lot of noise. This article use BEMD decomposes the fingerprint image. Each of the IMF obtained represents a particular scale. To some extent, it reflects the image texture information at different scales. The proposed algorithm use two-dimensional empirical mode decomposition to resolve the fingerprint image into a series of IMF and the residual. Take into account the distribution of noise between each component, the method use selected components to synthesis fingerprint image. It eliminates the effect of noise and enhance fingerprint image effectively.

Various TiO2 nanostructures, such as nanorings, nanorods were synthesized via potentiostatic anodization of titanium powder under different conditions. The morphology of the obtained TiO2 nanostructures can be easily tuned by varying applied voltage. The crystal structure, compositional information and morphological structures were characterized by X-ray diffraction (XRD), X-ray photoelectron spectra (XPS) and field emission scanning electronic microscopy (FESEM). XRD and XPS analysis confirmed the anodization products were TiO2. A possible formation mechanism was suggested on the basis of the shape evolution of TiO2 nanostructures observed by FESEM. The results revealed that the applied voltage played an important role in the formation of various nanostructures. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A biofilter packed with immobilized Thiobacillus sp. ST22 was investigated for the treatment of gases containing dimethyl sulfide (DMS). Thiobacillus sp. ST22 was immobilized using a sodium alginate, polyvinyl alcohol and powdered activated carbon as entrapping materials. The experimental results showed that the removal of DMS achieved an efficiency of 99.5%. The optimal spray density and empty bed residence time (EBRT) were 0.17 m3·m−2·h−1 and 21 s, respectively. Bacterial communities in the biofilter were assessed by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), which plays a dominant role in the biological processes of simultaneous sulfur oxidation and sulfate reduction. The results showed that Thiobacillus sp. ST22, delta proteobacterium were the predominant bacteria. Dimethyl sulfide can be oxidized into H2SO4, CO2 by Thiobacillus sp. ST22 biooxidation in the outer zones of immobilized cell beads due to aerobic conditions. Dimethyl sulfide can be degradated in...

A bench scale system integrated with a non-thermal plasma (NTP) and a biotricking filtration (BTF) unit for the treatment of gases containing dimethyl sulfide (DMS) was investigated. DMS removal efficiency in the integrated system was up to 96%. Bacterial communities in the BTF were assessed by PCR–DGGE, which play the dominant role in the biological processes of metabolism, sulfur oxidation, sulfate-reducing and carbon oxidation. The addition of ozone from NTP made microbial community in BTF more complicated and active for DMS removal. The NTP oxidize DMS to simple compounds such as methanol and carbonyl sulfide; the intermediate organic products and DMS are further oxidized to sulfate, carbon dioxide, water vapors by biological degradation. These results show that NTP–BTF is achievable and open new possibilities for applying the integrated with NTP and BTF to odour gas treatment.

Here we report a mini-three-dimensional dye-sensitized solar cell (3D DSSC) based on TiO2 nanotube arrays (TNAs). TNAs were directly grown on spiral-shaped titanium wire via a facile potentiostatic anodization. Furthermore, the TNAs film was characterized by scanning electron microscopy, x-ray diffraction and transmission electron microscopy, indicating that the annealed TNAs were composed of single-crystalline anatase particles. Unlike conventional flat DSSC, this mini-3D DSSC could easily hold liquid electrolyte due to the capillary force which facilitated sealing the cell. This mini-3D DSSC showed an energy conversion efficiency of 4.1% under the AM 1.5 condition, which was much higher compared with that (3.2%) of the backside illuminated TNAs based DSSC of the same projected area.

Here we report a frontside illuminated TiO2 nanotube based dye-sensitized solar cell (DSSC). The photoanode with inclined microchannels (IMCs) formed by laser drilling acted as a multifunctional role for enhancing the cell’s efficiency; light trapping, pathway for transporting electrolyte, and extra surface area for dye loading. The amount of N719 dye absorbed on IMCs photoanode was measured to be 3.83×10−7 mol/cm2, which was almost 1.82 times as high as that of the flat photoanode. The frontside illuminated DSSC showed an energy conversion efficiency of 4.1% under AM1.5 condition, which was much higher compared to that (3.1%) of the backside illuminated DSSC.

The objectives of this work were to investigate trimethylamine (TMA) removal by thermophilic biotrickling filtration (TBTF) and to examine the microbial community developed at 56 °C. TMA removal efficiency in the TBTF system was up to 99.9%. At a bed contact time of 25.8 s, the elimination capacity at 56 °C in the TBTF was 375.2 g TMA m −3 h −1 , which was higher than that of mesophilic biotrickling filtration. TBTF was able to quickly recover from a normal temperature shutdown period of a month. The thermophilic bacterial communities in the TBTF which were assessed by polymerase chain reaction–denaturing gradient gel electrophoresis (PCR–DGGE), play the dominant role in the thermophilic biological processes of metabolism, ammoxidation, nitrification, denitrification and carbon oxidation. These results show that TBTF is achievable and open new possibilities for applying biotrickling filtration to hot odorous gas streams from sewage sludge drying.