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Single-layer FeSe film on SrTiO3(001) has recently come to the fore as an interfacial superconducting system, with a transition temperature that is significantly enhanced with respect to bulk FeSe. The mechanism for this enhancement, and indeed for the superconductivity itself, is therefore of great interest. Although the film has a simple Fermi surface topology, its pairing symmetry is unclear. By using low-temperature scanning tunnelling microscopy, we have systematically investigated the superconductivity of single-layer FeSe/SrTiO3 films, and report a fully gapped tunnelling spectrum and magnetic vortex lattice in the film. Quasi-particle interference patterns reveal scatterings between and within the electron pockets, and put constraints on possible pairing symmetries. By introducing impurity atoms onto the sample, we show that magnetic impurities such as Cr and Mn can locally suppress the superconductivity, but non-magnetic impurities (Zn, Ag and K) do not. Our results indicate that single-layer FeSe/SrTiO3 has a plain s-wave pairing symmetry, with an order parameter that has the same phase on all Fermi surface sections. [ABSTRACT FROM AUTHOR]

In order to solve the shortcomings when removing lead from crude antimony in the traditional antimony smelting, a new process was provided using NaPO3 as lead elimination reagent to yield phosphate slag, and it was removed by floating on the surface of the liquid antimony. Reaction mechanism was clarified by using the TG-DTA and XRD techniques and single factor experiments of removal lead from crude antimony were engaged. The results show that PbO and NaPO3 begin endothermic reaction at 863K (590° C), and the reaction mainly form NaPb4(PO4)3 and NaPbPO4 below 1123K (850°C) and above 1123K (850°C), respectively. Sb2O3 and NaPO3 start the reaction at 773K (500°C) and generate an antimonic salt compound. The reaction product of the mixture of PbO, Sb2O3 and NaPO3 show that NaPO3 reacted with PbO prior when NaPO3 was insufficient, amorphous antimony glass will be generated only when NaPO3 was adequate. Single factor experiments were taken with NaNO3 as oxidizing agent under argon, effect of reaction time, reaction temperature and dosage of NaPO3 and NaNO3 on smelting results. The average content of lead in refined antimony was 0.05340% and 98.85% of lead were removed under optimal conditions; the content of lead in antimony have meet the requirements of commercial antimony. [ABSTRACT FROM AUTHOR]

Ta4Pd3Te16 is a newly discovered layered superconductor with quasi-one-dimensional (1D) structure. Recent thermal transport measurements show the possible existence of nodes in the superconducting gap. Here we report low-temperature scanning tunneling microscopy/spectroscopy study on Ta4Pd3Te16 single crystals. We observed stripelike structure composed of atom chains on the cleaved (103) surface. There exists charge-density-wave (CDW)-like modulations along stripes with commensurate periods. Meanwhile, the tunneling conductance shows an s-wave-like superconducting gap. The magnetic vortex mapped at low field is highly anisotropic with a bound state in the core. At increased field, strong vortex overlapping is directly observed and the bound state is suppressed, indicating the delocalization of the superconducting quasiparticles. Our observations suggest that Ta4Pd3Te16 is of multiband superconductivity with strong 1D characters, which possibly coexist with CDW transition. [ABSTRACT FROM AUTHOR]

A 2D C/SiC-BC x composite was tested under static load in both wet oxygen and dynamic combustion atmospheres. The microstructural evolution and self-healing mechanisms of the composites were investigated by a scanning electron microscope. The results indicated that the multi-scale deflection of cracks played an important role in improving the performance of 2D C/SiC-BC x in both atmospheres. The glass phase could seal the matrix cracks and flow into the fiber bundles through the cracks. As a result, the fibers and fiber/matrix interface within 2D C/SiC-BC x were protected from oxidation. The retention rate of high-temperature tensile strength of 2D C/SiC-BC x got a significant improvement in wet oxygen atmosphere at 700 °C, compared with 2D C/SiC. The damage rate of 2D C/SiC-BC x remained in a smaller scope in dynamic combustion atmosphere. The damage rates of the 2D C/SiC-BC x were about 80% and 90% lower than that of 2D C/SiC, respectively at 700 and 900 °C. [ABSTRACT FROM AUTHOR]

New composite particles of copper phthalocyanine (CuPc) via double modification of crude CuPc were prepared and characterised. Crude particles were suspended into the sodium oleate solution by ball milling method to obtain CuPc-1, which was subsequently coated with styrene through a miniemulsion polymerisation procedure to acquire CuPc-2 as an electronic ink material. The CuPc-2 ink particles were characterised by ultraviolet-visible spectroscopy and chroma. Scanning electron microscopy and transmission electron microscopy were employed to analyse the morphology and structure of CuPc-2. Furthermore, the functional group of the CuPc-2 was identified by Fourier transform infrared spectroscopy. The obtained CuPc-2 ink particles were then successfully incorporated in an electrophoretic display cell, and the contrast ratio of the same device was found to be 3·80. [ABSTRACT FROM AUTHOR]

Gd2Ti2O7 (GTO) single crystals having dimensions of 17 x 17 x 20 mm³ were grown by the Czochralski method. These crystals displayed a strong growth habit with {1 1 1} facets. The colors of the as-grown crystals were sensitive to the oxygen concentration both during growth and post-growth annealing. The possible reason for the different colors is discussed and based on transmission, energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and electron spin resonance (ESR) analyses. [ABSTRACT FROM AUTHOR]

An increase in interleukin ( IL)-17A-producing cells, particularly at sites of tissue inflammation, is observed frequently, yet the mechanism is not fully understood. This study aims to dissect the role of IL-17 in autoimmunity-mediated neuroinflammation. The cytokine milieu containing elevated IL-17, which often appears in active states of autoimmunity, was mimicked in vitro by a supernatant obtained from rat peripheral blood monocytes stimulated with phorbol mystistate acetate ( PMA)/ionomycin. The application of such inflammatory media on only primary cultured cerebellar granule neurones resulted in significant apoptosis, but the presence of astrocytes largely prevented the effect. The supernatants of the stimulated astrocytes, especially those that contained the highest level of IL-17, achieved the best protection, and this effect could be blocked by anti- IL-17 antibodies. Protein IL-17 inhibited intracellular calcium increase and protected the neurones under inflammatory attack from apoptosis. IL-17, but not interferon ( IFN)-γ, in the inflammatory media contributed to astrocyte secretion of IL-17, which depended on the Janus kinase/signal transducers and activators of transcription ( JAK/ STAT) pathway activation. The astrocytes that were treated with IL-17 alone or with prolonged treatment of the inflammatory media failed to produce sufficient levels of IL-17. Moreover, confirmatory data were obtained in vivo in a monophasic experimental autoimmune uveitis ( EAU) in Lewis rats; in this preparation, the high-level IL-17-containing the cytokine milieu was demonstrated, along with IL-17 secretion by the resident neural cells. The antagonism of IL-17 at a late stage disturbed the disease resolution and resulted in significant neural apoptosis. Our data show a dynamic role of IL-17 in the maintenance of homeostasis and neuroprotection in active neuroinflammation. [ABSTRACT FROM AUTHOR]

Vibration of the contact strip is an important phenomenon in the process of electrical sliding of a pantograph–catenary system. The correlation between the wear and vibration of a contact strip in a contact strip rubbing against a contact wire was studied. A series of experimental tests was conducted on a high-speed block-on-ring tester under electric current of 200 A, sliding speed of 160 km/h, and normal loads of 40–120 N. Scanning electron microscopy (SEM) and optical microscopy were used to observe the morphology of the worn surfaces. Experimental results indicate that the friction coefficient decreases but the wear rate of the contact strip increases with increasing vibration acceleration. Arc discharge energy increases with increasing vibration acceleration. Suppressing vibration is a practical way to decrease arc erosion wear of the contact strip. The conductivity of the contact strip becomes progressively worse with increasing vibration acceleration. [ABSTRACT FROM AUTHOR]