In this reported work, quarter-wavelength stepped-impedance resonators with K inverters have been employed to realise a dual-band bandpass Wilkinson power divider (WPD). The individual bandwidth of each passband can be controlled with the dualband resonators and K inverters. A systematic design approach of the power divider is provided with the aid of the even-odd mode analysis and verified by circuit simulation. A 2.45/5.8 GHz WPD with a Chebyshev response has also been implemented for validation. The measured fractional bandwidth of 20 dB return loss (1/|S 11 |) is 7.0%/4.1% which is consistent with the theoretical design. In addition to the 3 dB power division, an insertion loss of 0.8/1.2 dB is obtained. Isolation of 20.1/19 dB at the centre frequency is also achieved. Full-wave simulated data are also presented and show good agreement with measured results. Compared with other dual-band bandpass power dividers, the proposed circuit exhibits better impedance matching and bandwidth.

The recycling of tetra-pak packages composed of paper, low-density polyethylene (LDPE), and aluminum is of great recycling significance. The recovering of paper, the major component, was conducted through a Hydrapulper apparatus. The wet separation conditions of the remaining part, a laminated sheet composed of LDPE (0.03 ～ 0.08mm) and aluminum foil (0.02 ～ 0.03mm)(Al-PE), was studied in this paper. The separation effect of different separation reagents was compared, and the major process influencing factors, such as the separation reagent concentration, reaction temperature, liquid to solid ratio and solid size was studied. By orthogonal design experiment and variance analysis based on three evaluating indicators, the optimum condition of aluminum and LDPE complete separation using methanoic acid as separation reagent was obtained: 4 mol/L of methanoic acid concentration, 60 ℃ of reaction temperature, 60L/kg of liquid to solid ratio and 5×5cm of solid size, under which the separation rate would reach 100%.

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Bi-axial MEMS scanning mirrors are considered the key component for applications like laser scanning projectors and Lidars. Most studies have shown fabricated devices driven by open-loop operation without sensing, making it difficult to meet the requirements for practical applications. To facilitate bi-axial closed-loop operation, this work presents an electro magnetically-driven scanning mirror with piezoresistive sensing conveniently implemented in a CMOS (complementary metal oxide semiconductor) process. The measured resonant frequencies with respect to the slow and fast axes are 4.3 and 36.05 kHz, respectively, with the aim to provide SXGA display resolution.

The mechanism of negative bias temperature instability (NBTI) degradation in ultra deep submicron PMOSFET's is investigated. We mainly focus on the threshold voltage shift under subsequent positive bias temperature (PBT) stress after the preceding NBT. It's experimentally demonstrated that trapped holes from inversion channel and the diffusion of hydrogen molecules in the gate oxide are the major causes of NBTI degradation in PMOSFET's. When the condition is switched to PBT stress the trapped holes can be rapidly detrapped, but only a part of hydrogen molecules can diffuse back to the interface of gate oxide and substrate and repassivate silicon dangling bond, this is responsible for the threshold voltage being only partially recovered during PBT annealing.