Investigation on wear and rolling contact fatigue of wheel-rail materials under various wheel/rail hardness ratio and creepage conditions

The wear and rolling contact fatigue of wheel-rail materials were investigated through varying wheel/rail hardness ratios (Hw/Hr) and creepages. The results indicated that with the Hw/Hr increasing from 0.927 to 1.218, the wheel wear rate reduced significantly in the case of Hw/Hr = 1.218, the rail wear rate showed an increasing trend. Both the wheel and rail wear rates increased as the creepage enlarged. The synergistic results of Hw/Hr and creepage caused a transition of the wear and damage mechanisms on the wheel-rail steels. Besides, the fatigue damage of ER7 and CL60 wheel materials was dominated by slender multi-layer cracks, while the fatigue cracks were short and contained lots of interlayer broken materials on C-class wheel steel

An Integrated Modeling Approach for Predicting Process Maps of Residual Stress and Distortion in a Laser Weld: A Combined CFD–FE Methodology

Laser welding has become an important joining methodology within a number of industries for the structural joining of metallic parts. It offers a high power density welding capability which is desirable for deep weld sections, but is equally suited to performing thinner welded joints with sensible amendments to key process variables. However, as with any welding process, the introduction of severe thermal gradients at the weld line will inevitably lead to process-induced residual stress formation and distortions. Finite element (FE) predictions for weld simulation have been made within academia and industrial research for a number of years, although given the fluid nature of the molten weld pool, FE methodologies have limited capabilities. An improvement upon this established method would be to incorporate a computational fluid dynamics (CFD) model formulation prior to the FE model, to predict the weld pool shape and fluid flow, such that details can be fed into FE from CFD as a starting condition. The key outputs of residual stress and distortions predicted by the FE model can then be monitored against the process variables input to the model. Further, a link between the thermal results and the microstructural properties is of interest. Therefore, an empirical relationship between lamellar spacing and the cooling rate was developed and used to make predictions about the lamellar spacing for welds of different process parameters. Processing parameter combinations that lead to regions of high residual stress formation and high distortion have been determined, and the impact of processing parameters upon the predicted lamellar spacing has been presented

Digital processing of position error signal in hard disk drives

10.1109/IMTC.2004.1351237Conference Record - IEEE Instrumentation and Measurement Technology Conference21025-1029CRII

High-power fibre laser cleaning for green shipbuilding

Journal of Laser Micro Nanoengineering73249-25

Selective growth of gallium nitride nanowires by femtosecond laser patterning

10.1016/j.jallcom.2006.02.086Journal of Alloys and Compounds4491-2250-252JALC

Fabrication of nanostructures with laser interference lithography

10.1016/j.jallcom.2006.02.115Journal of Alloys and Compounds4491-2261-264JALC

SNP-mediated binding of TBX1 to the enhancer element of IL-10 reduces the risk of Behcet's disease

Aims: The genetic association between Behcet's disease susceptibility and IL-10 has been confirmed in multiple cohorts, but the underlying mechanism of this association remains unclear. Materials & methods: We combined public resources and laboratory experiments (electrophoretic mobility shift assays, chromatin immunoprecipitation, luciferase reporter gene and CRISPR/Cas9 genome editing) to analyze transcription factor binding and enhancer activity controlling IL-10 expression. Results & conclusion: The T allele of noncoding rs3024490 within super-enhancer elements is able to specifically bind TBX1 and, in turn, promotes the enhancer activity and increased expression of IL-10. However, a relative deficiency in TBX1 in Behcet's disease patients leads to the low expression of IL-10 and increased risk of developing Behcet's disease.Lay abstract Behcet's disease is an important cause of blindness. Previous reports show that genetic factors are linked with this disease, although the exact genetic mechanism is unclear. Many of these genetic factors are involved in the control of the immune response, including a large family of proteins known as cytokines. Some of the cytokines are proinflammatory while others can dampen the inflammatory response. An example of the latter is the IL-10 cytokine. We found that individuals carrying a specific site in the noncoding region of the IL-10 gene had a higher risk of Behcet's disease than other noncarriers. This study was designed to further investigate the biological mechanisms explaining the role of the specific site in the development of Behcet's disease. The results show that this specific site affects the binding of an important transcription factor, TBX1, which reduces IL-10 production. The dysregulated control of IL-10 explains why individuals with this genetic trait are more susceptible to developing Behcet's disease

Surface preparation for shipbuilding using pulsed high-power fibre laser

29th International Congress on Applications of Lasers and Electro-Optics, ICALEO 2010 - Congress Proceedings103451-45

Underwater laser cleaning for marine and offshore applications

29th International Congress on Applications of Lasers and Electro-Optics, ICALEO 2010 - Congress Proceedings103456-46