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Aluminum powder, stannous oxide powder and cuprous oxide powder are used for the preparation of tin oxide nanostructure in combustion synthesis-injection method with the formula designed using combinatorial chemistry method. The composition range of tin oxide nanostructure synthesis has been studied and the best formula of tin oxide nanowires synthesis has been screened. The research shows that the effective ingredient scope of tin oxide nanostructure is Al=30%~60%, CuO2=10%~50%, SnO=20% ~50% (mol), the main form of tin oxide nanostructure is nanowire and there are also forms such as nanorod, nanoparticle and nanobelt. The formula of tin oxide nanowire which leads to high yield, high purity and high conversion is Al:SnO:Cu2O=4:2:4(mol), the diameter of the tin oxide nanowires is within the range of 10~100 nm and most of them is from 40 to 60 nm, the highest conversion rate of SnO powder to SnO2 nanowire is 25.6%(mass), the tin oxide nanostructure synthesized by combustion synthesis-injection method has high purity, good dispensability, low preparation cost and it is also suitable for mass production.

With the increasing of extended warranty period for complex systems, the extended warranty has aroused more and more attention for manufacturers and consumers. Although the academic research on extended warranty has made some progresses, there isn’t a detailed literature review. Considering this situation, this paper first provides a classification for extended warranty, and develops a taxonomy scheme, then reviews the literatures about the extended warranty model from different perspectives. At last, the brief discussion of future research about extended warranty is put forward in this paper.

Polyimide (PI) was chosen as the matrix of the composites, barium titanate/polyimide (BT/PI) nanocomposite films were prepared with in-situ polymerization. The morphology of the samples was obtained by SEM. The factors affecting the dielectric properties are discussed. When the mass fraction of BT is 70%, the dielectric constant will be 19.32, and loss 0.00254 (at 103 Hz). The optimal solvent content and ultrasonic time were 9.2 ml and 30 min respectively. TG analysis shows that the film is stable below 500°C. The AC breakdown strength were 42 MV·m-1 and 64 MV·m-1 for 70% BT/PI and 60% BT/PI respectively, and corresponding energy storage density were 0.17 J·cm-3 and 0.30 J·cm-3 respectively.

Ni-doped ZnO diluted magnetic semiconductors nanorods were successfully synthesized by hydrothermal method. The crystal structure, morphology, constituent elements and optical proprety of the products using this method were investigated via X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray energy dispersive spectrometry (XEDS) and ultraviolet-visible spectroscopy (UV-vis). The experiment results show that the morphology of samples were nanorods with good dispersion, all the diffraction peaks correspond to the wurtzite structure hexagonal phase, no other impurity phase appeare, and the Ni2+ions successfully substituted for the lattice site and generate single-phase Zn1-xNixO. The band gap increases firstly and reduces afterward with the increase of Ni2+contents.

The StelliteNo6 alloy was surfaced on low carbon steel by plasma arc surfacing with LMF or TMF. The magnetic field current could been changed during surfacing. After plasma arc surfacing with magnetic field, the OM, XRD, wear loss test, micro-hardness test were used to analyze the effect of magnetic field style on microstructure and properties of overlay deposit. The acting mechanisms of magnetic field style and parameters on properties and microstructure of overlay deposit were researched. The results indicate that LMF and TMF all can improve the properties of overlay deposit. The active effect of TMF is better than LMF because of TMF can make the matrix metal γ-Co finer, second phase (CoCx、Cr7C3、Cr23C and FeNi) dispersion.

This paper presents a novel strategy for synthesis of carbon nanomaterials using the Cstaple biomaterials – starch as the starting materials. The carbonhydrate were vaporized by arc under helium, which leads to a large amount of monodispersive carbon nanoballs with range of 30-70nm in diameter. In addition to carbon nanoballs, some carbon nanocapsules were occasionally observed in products. Transmission electron microscopy (TEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD) were employed to characterizing products. The growth mechanism of carbon nanoballs is discussed briefly in terms of the precursor composition and process parameters.

Ag nanoparticles were successfully synthesized by hydrothermal method under the polyol system combined with traces of sodium chloride, Silver nitrate(AgNO3) and polyvinylpyrrolidone (PVP) acted as the silver source and dispersant respectively. The samples by this process were characterized via X-ray powder diffraction (XRD), Brunauer–Emmett–Teller (BET) adsorption equation, transmission electron microscopy (TEM) and the corresponding selected area electron diffraction (SAED) to determine the chemical composition, particle size, crystal structure and morphology. The experiment results indicate that the crystal structure of the samples is face centered cubic (FCC) structure as same as the bulk materials, The specific surface area is 24 m2/g, the particle size distribution ranging from10 to 50 nm, with an average particle size about 26 nm obtained by TEM and confirmed by XRD and BET results.

In the protecting inert gas, Aluminum nanoparticles were successfully prepared by anodic arc discharge plasma method. The morphology, particle size, crystal microstructure and specific surface area of the particles by this process were characterized via X-ray powder diffraction (XRD), Brunauer–Emmett–Teller(BET) adsorption equation, transmission electron microscopy (TEM) and the corresponding selected area electron diffraction (SAED). The experimental results indicate that the crystal structure of the samples is face centered cubic (fcc) structure as same as the bulk materials, the particle size distribution ranging from 20 to 70 nm, with an average particle size about 44 nm obtained by TEM and confirmed by XRD and BET results. The specific surface area is 41 m2/g, the nanopowders distributed uniformly in spherical chain shapes with uniform size and monodisperse particles.

In this paper, Silver nitrate(AgNO3) and polyvinylpyrrolidone (PVP) acted as the silver source and dispersant respectively, the silver nanowires including a small amount of folded structure of silver nanowires, were synthesized by hydrothermal method under the polyol system combined with traces of sodium chloride. The nanowires were characterized by X-ray powder diffraction(XRD), transmission electron microscopy(TEM), selected area electron diffraction(SAED), scanning electron microscopy (SEM), energy dispersive spectrometry (EDAX) and UV-vis absorption spectroscopy to determine the chemical composition, crystal structure, morphology,and the generation mechanism of Ag nanowires was also analysed. The experimental results showed that the crystal structure of the as-prepared Ag nanowires was fcc structure with uniform width, smooth surface, the diameter about 200nm,the average length about 15μm,and the aspect ratio up to 75.The folded structure of silver nanowires synthesized were due to the straight silver nanowires were connected in an end-to-end manner, with obvious spacing between them.

The high-phosphorus electroless Ni–P plating was coated on the surface of stainless steel. Five parameters, which have much effect on coating quality, were chosen to optimize the high-phosphorus electroless Ni–P plating technology in L16(45) orthogonal test. By means of x-ray diffraction and scanning electron microscopy, the morphologies and phase structures of coating were analyzed. Furthermore, the mechanical properties of coating were studied by micro-hardness tester and universal friction-wear testing machine. The results reveal that the optimal technical parameters are as follows: 20 g•L-1 for NiSO4, 23 g•L-1 for NaH2PO2, 15 g•L-1 for C6H5O7Na3•2H2O, 8 g•L-1 for H2N-CH2-COOH, 10g•L-1 for CH3COONa, 7 g•L-1 for C4H6O4, with PH value of 4.6, which leads to perfect coating quality. Besides, the P content is 11.64 wt.%, i.e. a high-P coating. The micro-hardness of the coating is 550.67 HV and the wear loss, 4.7×10-3 g. The thermal shock test suggests that between coating and matrix exist a perfect cohesion, which is due to the homogenous and compact coating, with an amorphous structure, under the condition of the optimal technical parameters.

Helical structure ZnS were successfully prepared via solvothermal method by the reaction of zinc acetate and sodium sulphide. The composition, morphology, and microstructure of the sample were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), the corresponding selected area electron diffraction (SAED) and X-ray energy spectrum (EDS). The experiment results show that the sample is 1-D hexagonal crystal ZnS and grows along the [002] direction, and is helical structure, with lengths in the range of 100-200 nm, the diameter about 5-15 nm, and pitch about 20nm.