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In this paper, a new approach of bidirectional electro-migration rehabilitation (BIEM) using pulse currents was proposed. The effect of the duty cycle and frequency of the square wave pulse current on the BIEM was investigated. The results showed that the desalination efficiency was improved by 10 % with the decrease of duty ratio and frequency. Furthermore, With the increase of duty ratio and frequency, the hydrogen permeation of steel bars decreased by 28.5 %. More uniform desalination efficiency was obtained by using pulse current. The half-cell potential of the rebars was also measured and it was higher for the samples using pulse currents than for those using direct currents, indicating a lower risk of corrosion after pulse current treatment. The pH value of the concrete also increased during the BIEM process. • The amount of hydrogen permeation in the rebars of concrete repaired by pulse current is reduced. • Increasing frequency and decreasing duty cycle of pulse current make the desalination efficiency distributed more evenly. • Decreasing frequency and duty cycle of pulse current will increase the efficiency of chloride ions removal. [ABSTRACT FROM AUTHOR]

SrFe 12 O 19 /CoFe 2 O 4 and SrFe 12 O 19 /Fe–B hard/soft magnetic composites were obtained by using powders synthesized via a hydrothermal and a molten salt method, respectively. The exchange coupling interaction was found to exist in the composites after a facile grinding according to the results of magnetic hysteresis loops and irreversible sloping recoil loops. It can be found that different grinding time affects their magnetic properties slightly. Our study proves that the conditions of realizing exchange coupling interaction may not be so stringent. [ABSTRACT FROM AUTHOR]

Laminated SiC/BN ceramics with a perfect layered structure was fabricated by tap-casting process and hot-pressing sintering. Damage resistance and R-curve behavior of laminated SiC/BN ceramics were evaluated using the indentation-strength-in-bending technique, and compared with those of monolithic SiC ceramics. The results showed that the indentation strengths for monolithic SiC ceramics decreased steeply with indentation load, while for laminated SiC/BN ceramics reduced slightly with indentation load, suggesting an exceptional damage resistance. Moreover, a rising R-curve behavior was demonstrated for laminated SiC/BN ceramics, a plateau R-curve behavior for monolithic SiC ceramics. The excellent damage resistance and pronounced R-curve behavior of laminated SiC/BN ceramics were attributed to crack deflection, crack branching and crack delamination at the SiC/BN weak interfaces. [Copyright &y& Elsevier]

• The copy number variation of SHANK3 contributes 0.4 % to Chinese children with ASD. • Comprehensive clinical, neurobehavioral, and brain imaging assessments were reported in SHANK3 deficient Chinese children. • SHANK3 -deficient ASD patients relate to the disrupted striatum centered connectivity. SHANK3 deficiency represents one of the most replicated monogenic risk factors for autism spectrum disorder (ASD) and SHANK3 caused ASD presents a unique opportunity to understand the underlying neuropathological mechanisms of ASD. In this study, genetic tests, comprehensive clinical and neurobehavioral evaluations, as well as multimodal structural MRI using voxel-based morphometry (VBM) and tract-based spatial statistics (TBSS) were conducted in SHANK3 group (N = 14 with SHANK3 defects), ASD controls (N = 26 with idiopathic ASD without SHANK3 defects) and typically developing (TD) controls (N = 32). Phenotypically, we reported several new features in Chinese SHANK3 deficient children including anteverted nares, sensory stimulation seeking, dental abnormalities and hematological problems. In SHANK3 group, VBM revealed decreased grey matter volumes mainly in dorsal striatum, amygdala, hippocampus and parahippocampal gyrus; TBSS demonstrated decreased fractional anisotropy in multiple tracts involving projection, association and commissural fibers, including middle cerebral peduncle, corpus callosum, superior longitudinal fasciculus, corona radiata, external and internal capsule, and posterior thalamic radiation, etc. We report that the disrupted striatum centered brain structures are associated with SHANK3 deficient children. Study of subjects with monogenic cause offer specific insights into the neuroimaging studies of ASD. The discovery may support a path for future functional connectivity studies to allow for more in-depth understandings of the abnormal neural circuits and the underlying neuropathological mechanisms for ASD. [ABSTRACT FROM AUTHOR]

Antimony selenide film doped with Zn2+ was deposited on ultra-white glass by hydrothermal method. The photocatalytic activity was evaluated by photocatalytic decolorization reaction with methylene blue (MB) solution. According to the free radical capture experiment, photogenerated holes (h+) and superoxide radicals (·O2−) are the decisive active substances in the photocatalytic process. [Display omitted] • Zn-doped Sb 2 Se 3 thin films prepared by hydrothermal deposition. • The amount of zinc doping is the key to the enhancement of photocatalytic activity. • The doping of Zn2+ increases the visible light absorbance of the Sb 2 Se 3 thin film. • Metal ion doping provides a simple method for metal selenide photocatalysts. Sb 2 Se 3 is a promising light-absorbing material with low cost and good photocatalytic activity. In this paper, Sb 2 Se 3 thin films doped with zinc (Zn) were deposited on ultra-white glass by hydrothermal method, using ZnCl 2 , sodium selenate and antimony potassium tartrate as raw materials. And the photocatalytic activity was evaluated by photocatalytic decolorization reaction with methylene blue (MB) solution. The results showed that the highest photocatalytic activity was displayed when Zn2+ was doped with 0.10 mmol, and its degradation rate of methylene blue was 1.66 times higher than that of pure Sb 2 Se 3. Zn2+ doped Sb 2 Se 3 film can effectively inhibit the recombination of electron-hole pairs, thereby improving the optical activity. According to the free radical capture experiment, photogenerated holes (h+) and superoxide radicals (·O2−) are the decisive active substances in the photocatalytic process. This method provides a reliable way for transition metal ions doped metal selenides to degrade organic dyes. [ABSTRACT FROM AUTHOR]

Abstract: This work reports a gel-casting technology without de-airing process developed to prepare mullite-based ceramics green body using silica sol as a binder. Concentrated alumina slurry dispersed in silica sol with high solid volume loading but low viscosity was successfully prepared at about pH 9.5. In-situ consolidation of the slurry was realized through adjustment of NH4Cl concentration to control the gelation time of the slurry. High compaction and uniform green body without air entrapped was obtained by gel-casting technology without de-airing process, and dense complex-shaped mullite-based ceramics were produced through the new gel-casting system. [Copyright &y& Elsevier]

• Pulse current make the potential distribution of concrete more uniform compared to direct current. • Increasing current density will increase the total concrete desalination efficiency. • Total concrete resistance increases during ECR process. • Pulse current repair is a suitable method to improve the efficiency of chloride removal. Electrochemical chloride removal (ECR) technique as an effective repair method has been applied to chloride-attacked concrete structures. This research studies the influence of different external electrical fields on the ECR treatment for reinforced concrete. Two types of electrical fields including direct and pulse current with average current densities of 2, 3 and 4 A/m2 were investigated. The chloride ion content of concrete before and after ECR treatment was determined. The results show that no matter what current density was used for concrete repair, the effect of pulse current on the desalination of concrete was better than direct current. Also, increasing the current density can also promote the concrete chloride removal efficiency. When applying a current density of 4 A/m2 to the steel rebars for 28 days, the remained chloride concentration of the concrete after ECR treatment was obviously lower than that of using 2 and 3 A/m2. In addition, the half-cell potential method was used to evaluate the rebar potential distribution. It was found that the pulse current can make the cathode reinforcement arranged in parallel in the concrete have a more uniform potential distribution, which indicates that the applied electrical current is easier to uniformly pass through the whole concrete structures. [ABSTRACT FROM AUTHOR]