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In this article, we report the first experimental results of a novel 4H-silicon carbide (SiC) p-i-n photodetector based on a vertical nanocone array (NCA). It is fabricated by electron beam lithography and inductively coupled plasma (ICP) etching technology. The performance of static and dynamic behavior was studied systematically. It shows the responsivity of ~41.9 mA/W under 360 nm at a bias voltage of -0.5 V and has a linear response to the ultraviolet (UV) light in a wide light intensity range of 0.1-10⁴ mW/cm². The response time decreased as the light intensity rose from 3 mW/cm² to 5 W/cm² and then leveled off at higher light intensity (>100 mW/cm²), which is about 0.25 ms. The photodetector -3-dB cutoff is ~3400 Hz at λ = 360 nm and light intensity = 100 mW/cm². Besides, the detector can respond to the UV light from 260 to 360 nm and the peak responsivity is ~78 mA/W at 320 nm. The analysis results have reference values for the development of an innovative 4H-SiC UV photodetector to some extent.

The tribological properties of graphene as grease additive were investigated under different contact forms and the worn surfaces were examined by X-ray photoelectron spectroscope (XPS) and Raman Spectrometer to reveal tribological mechanism. By the addition of graphene, the antiwear ability and friction reduction performance of grease were significantly improved. It is concluded that graphene can not only act as a deposition film to protect the substrate, but also stimulate formation of Fe2O3 and Li2O tribofilm. And the synergism of deposition film and tribo-chemical film significantly improve tribological properties of grease. In addition, the easy shear capability of graphene is prone to interlayer slip under the action of friction, thus decreasing the friction coefficient and promoting friction reduction performance of grease.

In the present study, triangular copper nanoplates have been prepared with CTAB as the capping reagent and ascorbic acid as the reductant. This study also provides quantitative analyses on the effects of pH and CTAB on the structural characteristics of the nanoplates. When the reaction takes place at a pH = 7 with a CTAB concentration of 0.06 M, the resulting triangular nanoplates appear to have well-defined and identical structures. As an additive for greases, the nanoplates are responsible for the formation of a film deposit at the interface of the friction pair during friction. The effects of which are a 12% drop in the friction coefficient of the grease and an 82.2% drop in wear loss, which, in turn, significantly improve the tribological properties of the lubricant.

For design of automotive airbag electronic control units (AB ECU), it is essential to have a validated and reliable finite element (FE) simulation model in place in order to allow already in an early design stage for the accurate prediction of the ECU’s structural vibration behavior. A “bottom-up” approach which described in the ASME guide for verification and validation (ASME V&V 10-2006) is applied for the validation of the AB ECU simulation model. The AB ECU is decomposed into different assembly level. Single printed circuit board (PCB) is the lowest elementary component level. In the PCB level simulation and validation, the influence of in-plane pre-stress on PCB’s transverse vibration characteristic has been encountered, but it has been found out that the source of the in-plane pre-stress can not be explained by classical beam/plate theory. Analysis and simulation for PCB fixation reveals that the fundamental source of the in-plane pre-stress is structure’s geometric nonlinearity.