A coaxial nonthermal plasma (NTP) reactor was used for oxidizing and removing NO in mist. The effects of gas/mist components on O3 formation, NO oxidation, and NO x removal by NTP in simulated flue gas after wet desulfurization were investigated. The presence of mist results in the significant decrease of O3 concentration. Formation of active species, such as OH and HO2, would promote the reactions between NO and OH/HO2. Thus, the NO oxidation, NO x removal, and energy efficiency are significantly improved in the presence of mist. The promotion effects of mist component on the NO oxidation and NO x removal follow the order: Na2SO3 mist > FeSO4 mist > Na2SO4 mist. Increase of the mist pH can enhance the absorption of nitrogen oxides with the mist. Adding SO2 to the gas mixtures or raising the NO2/NO x ratio of simulated gas increases the NO x removal efficiency. This process demonstrates that NO oxidation by NTP and subsequently absorption by mist are feasible and have great value to practical application.

Purpose: The aim of this study is to explore how pedicle screws (PSs) and cortical bone trajectory (CBT) screws differ in fixation strength when implanted in L1–L5 with osteoporosis, providing support for choosing implants and trajectories in spine internal fixation surgeries. Methods: We filtered 30 lumbar segments out from CT images of eight osteoporotic participants and simulated PS or CBT screw implantation in each segment, generating 60 vertebra-screw assembly FE models. To evaluate the fixation effect, we performed a pull-out force test simulation in each model and analyzed the maximal pull-out force, pull-out stiffness, and equivalent stress of vertebrae and screws. Results: The maximal pull-out force of PS and CBT screws in L1–L5 was in the range of 905–1552 (N) and 587–1012 (N), while the pull-out stiffness was in the range of 1990–2617 (N/mm) and 1007–1681 (N/mm). The fixation strength of PS in L4 and L5 was higher ([Formula: see text]), while in L1–L3 PS and CBT screws are similar ([Formula: see text]). The maximal stress of vertebrae and screws when PS was pulled at 0.25[Formula: see text]mm was larger than that of CBT screws. Conclusions: For patients with moderate osteoporosis, it is recommended to insert PS into L4 and L5 to attain better fixation strength, but vertebrae are more prone to fracture. Consequently, under severe osteoporosis, the implantation of CBT screws should be considered first. Bone cement injection may be necessary to consolidate the screw-vertebrae interface with osteoporosis.

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Human body finite element (FE) models can be used for seating comfort assessment by providing biomechanical related parameters such as internal loads and soft-tissue deformations. However, most of the published models were only validated under a condition far from a real seating situation. Their ability to be repositioned may also be limited. In recent years, an open-source PIPER software package has been developed to help personalize and position Human Body Models (HBMs) for crash simulation. We have morphed the PIPER Child model into an adult FE model. In this paper, we present how the initially morphed adult FE model was adapted for assessing seating comfort and validated for different seating conditions.Experimental data was collected using a reconfigurable experimental seat and pressure mats. Four seat configurations were defined with the seat pan angle (SPA) from 0° to 15° (5° in steps) and seat pan to seat backrest angle (SP2BA) kept to 100°. Simulated results in terms of seat contact area (ContactA), peak pressure (PeakP), mean pressure (MeanP), and pressure profiles showed good agreement with experimental observations. The full-body FE model developed and validated in this work will be used as a reference for further development of scalable and positionable models using the PIPER software framework. The model will be open source to facilitate reuse and further improvements.