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The TiAlLaN films were deposited on YG8 and silicon (1 1 1) substrates by a hybrid PVD coater which is combined with medium frequency reactive magnetron sputtering and ion-plating evaporation. The effects of lanthanum addition and bias voltages on the composition, crystal morphology, microstructure, mechanical properties, and oxidation resistance of the TiAlLaN films were investigated systematically. With lanthanum addition in the TiAlN film, the crystal morphology changed from columnar to equiaxial, and the grain refinement accompanied by the increase of hardness and elastic modulus was found. The indentation adhesion test showed that the adhesion strength was deteriorated by adding lanthanum in the deposited film; however, the scratch adhesion test expressed a better morphology of the scratch track line for the TiAlLaN film. With the substrate bias increasing, the elements concentration of films were alternated, and the equiaxial crystals were turned to columnar crystals. The oxidation resistance of the deposited films increased with the increase of bias voltage. The adhesion qualities, which are affected by the increasing hardness and elastic modulus, were worse for the TiAlLaN films under higher bias voltages. The TiAlLaN film under the bias of −10 V showed the highest H/E ratio.

TiAlSiN coatings with Ti or Cr interlayers were deposited on high-speed steel using magnetron sputtering methods. The structure, crystal morphology and mechanical properties were investigated systematically. The results show that (200) is the dominant preferred orientation in Ti/TiAlSiN coating, while (111) become the predominant orientation of the deposited Cr/TiAlSiN coating, which is related to the surface energy. Due to the changes of the coating growth style, the Cr/TiAlSiN coating shows columnar crystals morphology. The Ti/TiAlSiN coating performs better adhesion and H/E ratio, which is proved to have better wear resistance. But the specimens with Cr interlayer have better hardness and elastic modulus, which is due to the growth style of the crystals.

TiAlLaN coatings were deposited on the cemented carbide substrates by mid-frequency magnetron sputtering system. The effects of Ar/N2 flow ratio on the composition, structure, adhesion and hardness followed with elastic modulus and H/E ratio were investigated systematically. Results indicate that all the Ti/Al ratios of the coatings were higher than that of the Ti/Al ratio in the target; however, the Ti/Al ratio increased with the Ar/N2 flow ratio changed. XRD patterns show that the intensity of (111) peak was elevated with the Ar/N2 flow ratio increased. Meanwhile, the peak shifted to lower angles, which implied increases of the lattice parameter. The TiAlLaN coating under the Ar/N2 flow ratio of 3:1 showed the best adhesion, the highest hardness and the lowest H/E ratio which indicated perfect wear resistance.

The purpose of this paper is to establish a three-dimensional model of sliding friction and to study the influence of surface topography fractal parameters on the model. Firstly, the analysis of the contact between two asperities is completed, for according to the classical molecular-mechanical friction theory, the sliding friction among rough surfaces should be the sum of mechanical force and molecular adhesion. Then based on the fractal theory, the three-dimensional fractal model of sliding friction is deduced. Finally, the influence of the maximum contact area of asperity al, the fractal roughness G and the fractal dimension D on the sliding friction is analyzed by a simulation example, and the analysis results show that the sliding friction F has positive correlation with al and G, and there is an optimal fractal dimension D which minimizes F. The study of the paper can be used to explain the existing experimental results and the friction theory reasonably.

Surface-layer associated proteins (SLAP) that envelop Lactobacillus paracasei ssp. paracasei M5-L and Lactobacillus casei Q8-L cell surfaces are involved in the adherence of these strain to the human intestinal cell line HT-29. To further elucidate some of the properties of these proteins, we assessed the yields and expressions of SLAP under different incubation conditions. An efficient and selective extraction of SLAP was obtained when cells of Lactobacillus were treated with 5 M LiCl at 37°C in aerobic conditions. The SLAP of Lactobacillus M5-L and Q8-L in cell extracts were visualized by SDS-PAGE and identified by Western blotting with sulfo-N-hydroxysuccinimide-biotin-labeled HT-29 cells as adhesion proteins. Atomic force microscopy contact imaging revealed that Lactobacillus strains M5-L and Q8-L normally display a smooth, homogeneous surface, whereas the surfaces of M5-L and Q8-L treated with 5 M LiCl were rough and more heterogeneous. Analysis of adhesion forces revealed that the initial adhesion forces of 1.41 and 1.28 nN obtained for normal Lactobacillus M5-L and Q8-L strains, respectively, decreased to 0.70 and 0.48 nN, respectively, following 5 M LiCl treatment. Finally, the dominant 45-kDa protein bands of Lactobacillus Q8-L and Lactobacillus M5-L were identified as elongation factor Tu and surface antigen, respectively, by liquid chromatography-tandem mass spectrometry.