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EAF-dust containing metal oxides can be regarded as an important source for zinc and iron. In this study, the reduction behavior of zinc ferrite with CO gas as a reducing agent under different temperatures was investigated to develop a new process for the recovery of zinc and iron from EAF-dust. The results of the phase studies with synthetic franklinite show that zinc substituted wustite, and spinel with low zinc content formed at lower temperatures from 450 to 850 °C due to incomplete zinc–iron-separation. Zinc ferrite was completely reduced to metallic zinc and iron at 950 °C. After evaporation and condensation, metallic zinc was collected in the form of zinc powder while iron, the reduction residue, was obtained in the form of direct reduced iron (DRI). The mass balance indicates a high zinc recovery ratio of over 99%. The new treatment process by thermal reduction with CO gas as a reducing agent achieved higher recovery and metallization grade of both zinc and iron from EAF-dust at lower temperatures than other commercial processes. The metallic products can be used directly as semi-products or as raw materials for refinery. [Copyright &y& Elsevier]

Abstract: A barrier structure consisting of SiO x and SiN x films was deposited on the polymer substrate at 80°C via plasma-enhanced chemical vapor deposition (PECVD). However, the low radius of curvature (R c) of the barrier-coated substrate may cause the inconvenience of the following fabrication processes. By depositing a 150nm-SiN x film, the R c of the barrier-coated polycarbonate (PC) substrate can increase from 80 to 115mm without inducing any cracks in the barrier structure. Furthermore, the thermal stress of the barrier structure can be adjusted via extending the PECVD process duration in the chamber and replacing PC by the polyethersulone (PES) substrate. The R c can increase to ∼356mm by depositing the 150nm-SiN x film on the other side of the PES substrate. Finally, the calcium test result of the barrier films/PES/SiN x sample was calculated to be around 3.05×10−6 g/m2/day, representing that the barrier structure did not fail after modification. [Copyright &y& Elsevier]

T cells with CD4–CD8– (double negative, DN) phenotype in MRL-lpr/lpr mouse serve as a model to establish the correlation between the extremely low IL-2 gene expression and the specific signaling inactivation. The extent of nonresponsiveness in lpr DN cells was distinctive in several unusual defects. First, the poor IL-2 production in lpr DN cells could not be restored by supplement of signals known to augment IL-2 response in normal T cells. Second, the activations of both mitogen-activated protein (MAP) kinase and c-Jun N-terminal kinase (JNK) were attenuated in lpr DN cells upon direct activation by TPA/A23187. Third, IL-2 mRNA was degraded much faster in lpr DN cells than that in normal T cells. Fourth, of the four major transcriptional elements on IL-2 promoter, only AP-1 and nuclear factor of activated T cells (NFAT)-binding activities were suppressed in lpr DN T cells. Altogether, these results suggest that an extremely low level of IL-2 production in lpr DN T cells was due to both the increased instability of mRNA and the reduced activation of IL-2 gene promoter, the latter defect could be attributed to the inactivation of AP-1 and NF-AT as well as the poor activation of the upstream MAP kinase and JNK. [ABSTRACT FROM AUTHOR]

The identification of threshold function (TF), which determines whether a Boolean function can be represented by an linear threshold logic gate (LTG) or not, is a fundamental but important task in the theories of threshold logic. In this paper, we propose a more efficient and effective algorithm of TF identification by constructing the system of irredundant inequalities and adjusting the weight assignment comprehensively. This is the first non-ILP-based approach that is able to identify all the eight-input TFs. The experimental results demonstrated that the proposed approach is more effective than all the existing non-ILP-based approaches and the LTGs obtained by the proposed approach are optimal for near 100% cases. For TFs with 9–15 inputs, the proposed approach can identify 100 000 randomly generated TFs as well in a reasonable CPU time. [ABSTRACT FROM AUTHOR]

Abstract: A surface‐enhanced Raman spectroscopy (SERS) detection method that allows dynamic on‐demand generation of SERS substrates at locations of interest for in situ molecular sensing is demonstrated. Thermal convection and thermophoresis, which are both generated in a laser‐induced temperature gradient, are used to accumulate suspended plasmonic nanostructures to form 3D SERS substrate. Raman signals of melamine, which is used as a model analyte, increase to ≈117‐fold within 2 min of laser irradiation because of the accumulation. In addition, it is demonstrated that the accumulation of the nanostructures is reversible, and that reproducible SERS effects can be obtained during a repeated heating and cooling process. Because of the capability of on‐demand generation of a high density of SERS hot spots at different locations in solution, this particle manipulation and SERS detection method is applicable to monitor temporal and spatial variations of the concentrations of molecules. The complexity of the detection system remains the same when using this method since all the measurements are performed with a conventional Raman system and simple fluid channels. The required temperature gradient is generated by the laser used to excite Raman signals, and no nanofabricated substrates and complicated microfluidic or optical components are needed. [ABSTRACT FROM AUTHOR]

Abstract: A barrier structure consisting of silicon oxide and silicon nitride films was deposited via plasma-enhanced chemical vapor deposition (PECVD) for the encapsulation of polymer solar cells (PSCs). The total concentration of the solution and the ratio of P3HT and PCBM on the performance of polymer solar cells were studied by UV–Vis absorption spectroscopy, atomic force microscopy and photocurrent measurement. Base on these measurements, there is a compromise between light absorption and phase separation with increasing blend concentration. The PSCs were annealed at 80, 100, 120 and 140 °C for 10–60 min to investigate the thermal effects and to estimate the best deposition temperature of the barrier layers. Nevertheless, the devices with the encapsulation of barrier layers had relatively low power conversion efficiencies (PCE) of 0.98% comparing to the devices heated in the PECVD system (1.57%) at the same condition of 80 °C for 45 min due to the plasma damage during the film deposition process. After inserting a 5-nm TiO x layer between Al/barrier structure and active layer against the plasma damage, the annealed devices presented an average PCE of 2.26% and demonstrated over 50% of their initial value after constant exposure to ambient atmosphere and sunlight for 1500 h. [Copyright &y& Elsevier]