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The fixed scroll of the scroll compressor is usually immovable, and the deformation of the scrolls may lead to the operation stuck, which may be avoided by designing the fixed scroll as floating one. However, the introduction of floating fixed scroll will inevitably cause the variation of the dynamic characteristics, so it is necessary to establish a simulation model to explore the influence of floating fixed scroll. In this study, a tribo-dynamics model considering floating fixed scroll is established, which couples the key friction pairs composed of fixed scroll, orbiting scroll and frame to reveal the influence of floating scroll on tribological and dynamics performance. The variation of the lubricant viscosity and boundary pressure as well as the deformation of components are included in the model to consider the real working conditions. The results show that compared with the fixed scheme, the floating scheme provides a compensation space for the components deformation, which is conducive to the operation stability; The floating scheme can not only ensure the sealing of the compression chamber, but also reduce the friction work by 53% compared with the fixed clearance of 4µm. [ABSTRACT FROM AUTHOR]

The Oldham's ring is a key component to prevent the orbiting scroll from rotating, and the complex working conditions make its keys wear, which seriously affect the reliability of the scroll compressor. In order to simulate the real working state and explore the wear reduction scheme of the Oldham's ring, an 8 degrees of freedom (DOF) tribo-dynamics model with multi-component coupling is established in this study, and the variations of lubricant viscosity, boundary pressure and the deformation of components are considered. The results show that the quadratic-function profile of the Oldham's ring keys significantly affects its dynamics properties, and the profile with a height of 3 µm can reduce the wear by 59% compared with no profile. [ABSTRACT FROM AUTHOR]

Investigates the annealing behavior of amorphous germanium bilayer thin films. Applications of amorphous germanium bilayer films; Details on the experiment; Discussion on the results of the study.

The objective of the present study is to provide understanding of potential energy absorption and dissipation mechanisms and benefits of topologically interlocked material (TIM) assemblies under impact loading. The study is motivated by earlier findings that TIMs under low rate loading demonstrated attractive properties including the capability to arrest and localize cracks and to exhibit a quasi-ductile response even when the unit elements are made of brittle materials. It is hypothesized that TIMs due to their modularity would possess advantageous impact characteristics. In order to test this hypothesis, a series of computational experiments on the dynamic loading of TIMs are conducted. Results obtained in this study are presented for a planar TIM configuration based on a dense packing of tetrahedral unit elements to form an energy absorption layer. Finite element models are calibrated on samples fabricated using fused deposition modeling (FDM) additive manufacturing (AM). With employing the Lambert–Jonas formula to interpret the numerical data, it is demonstrated that TIMs can absorb more impact energy than conventional solid plates. An extended Lambert–Jonas model is defined such that accurate description of the impact response of TIMs is obtained. [ABSTRACT FROM AUTHOR]

This work reports on the role of the synergy peptide PHSRN in mediating the adhesion of cells. The attachment of baby hamster kidney cells and 3T3 Swiss fibroblasts to model substrates presenting either GRGDS or PHSRN was evaluated using self-assembled monolayers of alkanethiolates on gold presenting the peptide ligands mixed with tri(ethylene glycol) groups. These substrates permit rigorous control over the structures and densities of peptide ligands and at the same time prevent nonspecific interactions with adherent cells. Both cell types attached efficiently to monolayers presenting either the RGD or the PHSRN peptide but not to monolayers presenting scrambled peptide GRDOS or HRPSN. Cell attachment was comparable on substrates presenting either peptide ligand but less efficient than on substrates presenting the protein fibronectin. The degree of cell spreading, however, was substantially higher on substrates presenting RGD relative to PHSRN. Staining of 3T3 fibroblasts with anti-vinculin and phalloidin revealed clear cytoskeletal filaments and focal adhesions for cells attached by way of either RGD or PHSRN. Inhibition experiments showed that the attachment of 3T3 fibroblasts to monolayers presenting RGD could be inhibited completely by a soluble RGD peptide and partially by a soluble PHSRN peptide. IMR 90 fibroblast attachment to monolayers presenting PHSRN could be inhibited with anti-integrin α5 or anti-integrin β antibody. This work demonstrates unambiguously that PHSRN alone can support the attachment of cells and that the ROD and PHSRN bind competitively to the integrin receptors. [ABSTRACT FROM AUTHOR]