An Analysis of the Performance of Trolleybus Brushes Developed from Recycled Materials

The paper presents an analysis of the performance of traction brushes produced from waste materials. Brushes are used to ensure good electrical contact between the rail and the pantograph. Slides are produced by the process of hot pressing, with the parameters of heating up to max 175 °C, at the minimal pressure value of 200 MPa. Some of the developed brushes with a high (55–60%) content of recycled materials are more durable and break-resistant than their commercial counterparts.

An Analysis of the Possibility to Develop Trolleybus Current Brushes From Recycled Materials

The paper presents an analysis of the possibility of producing traction brushes from waste materials. Brushes are used to ensure good electrical contact between the rail and the pantograph. Slides are produced in the process of hot pressing, with parameters of heating up to max 175 ⁰C, at the minimal pressure value of 200 MPa. The developed brushes with a high (55-60%) content of recycled materials have comparable characteristics to commercial brushes, and some of the prototypes are even more durable and break-resistant.

FeOx@carbon yolk/shell nanowires with tailored void spaces as stable and high-capacity anodes for lithium ion batteries

Porous FeOx@C yolk/shell nanowires with optimized void space delivered a stable cyclability over 400 cycles, high capacities and a good rate capability. The optimized void space contributes to preserve structural integrity and maintain good electrical contact between FeOx and C.

Scaling the 3D Bumps Pitch from 20 to 10 μm, Focusing on the Wet Cu Seed Etch Process Development

Within 3D stacked integrated circuits (3D-SIC), the fabrication of well-defined and solid microbumps is required. These bumps are typically being processed in presence of probing metal such as Al in order to stack functioning dies [1]. As a result of the variety of metals present and the continuous microbump downscaling towards 10 μm, more selective Cu seed etch chemistries are being screened. These Cu seed etch chemistries should be compatible with a variety of metals (Ni, Sn, Al, Co) and generate bumps without undercut and acceptable lateral etch (< 300 nm/side for 20 μm and < 150 nm/side for 10 μm). However the lateral etch specifications were just met for 20 μm [2] and will be more stringent for 10 μm, especially as the lateral etch specification are within the same range as the Cu seed layer thickness (150 nm). Additionally, the current seed etch process is yielding rough bumps (Rs >15 nm) whereas our target is set to be <12 nm in order to guarantee a good electrical contact.

Rand- und Grenzbedingungen in der Theorie stark verunreinigter Supraleiter

The kernel of the linearized integral equation for the order parameter Δ (r) was shown] by DE GENNES to be the solution of a diffusion equation in the case of a very impure superconductor. On the basis of the method of the correlation function originating from DE GENNES and further developed by LÜDERS, boundary conditions to the diffusion equation are derived for surfaces and for interfaces between different conductors. In the case of good electrical contact, our results are identical with those given by DE GENNES.