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Due to its intricate operational environment, substantial mass, and elevated center of mass, the three-axle emergency rescue vehicle is more prone to rollover. This study aims to enhance the operational stability and mitigate rollover risks by establishing a rollover dynamic model with 11 degrees of freedom. Using the coupling characteristics of vehicle dynamics and tire force, an anti-rollover control strategy of the three-axle vehicle based on the cooperative work of differential braking and active suspension is proposed. According to the vehicle motion characteristics, the active suspension controller is built by using a fuzzy PID algorithm, and the differential braking controller is built by using the improved adaptive model predictive control algorithm. The step and fishhook tests of differential braking, active suspension control and joint control are carried out respectively. The simulation results show that the joint control strategy can effectively reduce the rollover tendency of the vehicle, and further improve the anti-rollover ability of the vehicle compared with the single system control.

Highly selective molecularly imprinted nanocomposites MIPRhB-PPy/TiO2 were successfully prepared by surface molecular imprinting technique with rhodamine B (RhB) as template molecule. The prepared MIPRhB-PPy/TiO2 coated with a thin imprinted layer could respond to visible light. The static and dynamic binding experiments revealed that MIPRhB-PPy/TiO2 possessed strong affinity, high adsorption capacity and fast adsorption rate for RhB. The selectivity experiments indicated that MIPRhB-PPy/TiO2 had excellent recognition selectivity for RhB. Selective photocatalytic degradation experiments indicated that the apparent rate constant (k) for the photodegradation of RhB over MIPRhB-PPy/TiO2 is 0.0158 min–1, being 3.6 times of that over non-imprinted nanocomposites NIPRhB-PPy/TiO2 (0.0044 min–1). Compared with the NIPRhB-PPy/TiO2, MIPRhB-PPy/TiO2 showed higher photocatalytic selectivity toward RhB under visible light, which was attributed the introduction of the imprinted cavities on the surface of MIPRhB-PPy/TiO2. Moreover, MIPRhB-PPy/TiO2 exhibited high reusability and stability. The results indicate that molecularly imprinted nanocomposites MIPRhB-PPy/TiO2 have a promising perspective in industrial wastewater treatment.

We aimed to describe the surgical technique and clinical outcomes of paraspinal-approach reduction and fixation (PARF) in a group of patients with Denis type B thoracolumbar burst fracture (TLBF) with neurological deficiencies. A total of 62 patients with Denis B TLBF with neurological deficiencies were included in this study between January 2009 and December 2011. Clinical evaluations including the Frankel scale, pain visual analog scale (VAS) and radiological assessment (CT scans for fragment reduction and X-ray for the Cobb angle, adjacent superior and inferior intervertebral disc height, and vertebral canal diameter) were performed preoperatively and at 3 days, 6 months, and 1 and 2 years postoperatively. All patients underwent successful PARF, and were followed-up for at least 2 years. Average surgical time, blood loss and incision length were recorded. The sagittal vertebral canal diameter was significantly enlarged. The canal stenosis index was also improved. Kyphosis was corrected and remained at 8.6±1.4o (P>0.05) 1 year postoperatively. Adjacent disc heights remained constant. Average Frankel grades were significantly improved at the end of follow-up. All 62 patients were neurologically assessed. Pain scores decreased at 6 months postoperatively, compared to before surgery (P

ZnO/Mg0.2Zn0.8O multiple quantum wells (MQWs) were grown on a c-plane sapphire (Al2O3) substrate by plasma-assisted molecular beam epitaxy. Both the spontaneous and the stimulated emission properties at room temperature (RT) in MQWs were studied under lower and higher excitation densities. The strong emission at 3.330 eV was observed in the MQWs at RT, which was attributed to the free exciton transition by the temperature-dependent photoluminescence measurement. Significantly, RT stimulated emission caused by inelastic exciton-exciton scattering was observed in the ZnO/Mg0.2Zn0.8O MQWs grown on Al2O3. Thus, the exciton binding energy was determined to be 122 meV in our MQWs. [ABSTRACT FROM AUTHOR]

ZnO nanocrystals (NCs) embedded in a BaF2 matrix have been prepared by a radio-frequency magnetron sputtering technique followed by a thermal annealing process from 400 to 1100 degC. X-ray diffraction results show that ZnO NCs with a hexagonal wurtzite structure are formed in a BaF2 matrix. The average grain sizes are estimated ranging from 7.5 to 33 nm, corresponding to fabricated samples annealed at temperatures from 400 to 800 degC. Photoluminescence showed a very strong ultraviolet near-band-edge (NBE) emission located in the 364-383 nm spectral region. The emission intensity is enhanced and the linewidth is narrowed as the annealing temperature increases. The intensity ratio of ultraviolet NBE emission to deep-level visible is also increased with annealing temperature indicating that deep-level defects in ZnO are suppressed. [ABSTRACT FROM AUTHOR]

Zn0.8Mg0.2O metal-semiconductor-metal ultraviolet photodiodes were fabricated on quartz by radio frequency magnetron sputtering. Dark current, spectral responsivity and pulse response experiments were carried out for the device. The photodetectors showed a peak responsivity at 330?nm. The ultraviolet-visible rejection ratio (R330?nm/R400?nm) was more than four orders of magnitude at 3?V bias. The photodetector showed fast photoresponse with a rise time of 10?ns and a fall time of 170?ns. In addition, the thermally limited detectivity was calculated to be 3.1 × 1011?cm?Hz1/2?W?1at 330?nm. [ABSTRACT FROM AUTHOR]

Electrical transport properties of p-type ZnO:N films grown by thermal activation of the nitrogen dopant were investigated via the temperature-dependent Hall effect. The Hall mobility increases with decreasing temperature. Varied scattering mechanisms have been analysed including lattice vibration scattering, ionized impurity scattering and dislocation scattering. A fit of the theory to temperature-dependent hole mobility experimental data in p-type ZnO:N films gives dislocation densities in the order of 1012cm?2. The analysis shows dislocation scattering is indeed important for the p-type ZnO films grown on the mismatched substrate. The thermal ionization energy of the nitrogen acceptor is estimated to be 170 meV in terms of the temperature-dependent hole concentration. On the other hand, the emission related to the acceptors is observed in PL spectra. [ABSTRACT FROM AUTHOR]

A lithium (Li) and nitrogen (N) dual-doped p-type ZnO film (ZnO?:?(Li,N)) was deposited on c-plane sapphire by RF-magnetron sputtering of Zn-2?at.% Li alloy using mixed gases of oxygen and nitrogen and then annealing in N2flow. It has a carrier concentration of 3.07 × 1016?cm?3and Hall mobility of 1.74?cm2?V?1?s?1. XPS measurement shows that there are LiZn-N complexes in the p-type ZnO?:?(Li,N), which are demonstrated by photoluminescence measured at various temperatures and different excitation powers to be acceptors and responsible for p-type conductivity of the ZnO?:?(Li,N). The optical level of the LiZn-N complex acceptor is estimated to be about 126?meV by measurement of emission energy of free electron to the acceptor level. [ABSTRACT FROM AUTHOR]

Catalyst-free needle-like ZnO nanowires have been grown on Si(111) substrate at 430 °C via a simple solid–vapour process. The obtained nanowires are found to have a uniform size distribution with sharp tips. The lengths of the nanowires range from 2.8 to 3.2 µm with diameters of about 100 nm for the root and 30 nm for the tip parts. The x-ray diffraction (XRD) result shows the nanowires are c-axis preferentially oriented. Transmission electron microscopy (TEM) and selected area electron diffraction (SAED) analysis reveal that every single nanowire is a well developed single crystal. The room temperature photoluminescence (PL) spectrum shows a dominant near-band-edge emission peak. The near-band-edge emission is further identified to originate from the radiative free exciton recombination by the temperature-dependent PL. [ABSTRACT FROM AUTHOR]

A series of MgxZn1-xO thin films has been prepared by metalorganic chemical vapor deposition and metal-semiconductor-metal structured ultraviolet photodetectors are fabricated from these films. The cutoff wavelengths of the photodetectors can cover the whole solar-blind spectrum range (220–280 nm) by varying Mg content in the MgxZn1-xO thin films. As a representative, the photodetector fabricated from Mg0.52Zn0.48O shows an ultraviolet/visible rejection ratio of about four orders of magnitude, and the dark current is 15 pA at 10 V bias. These results demonstrate that high-performance photodetectors operating in the whole solar-blind spectrum range can be realized in MgxZn1-xO films. [ABSTRACT FROM AUTHOR]

Cubic MgxZn1[?]xO thin films (x = 0.70) were grown on quartz substrates by radio frequency magnetron sputtering and a metal-semiconductor-metal structured photodetector was fabricated based on the film. The photodetector exhibited a dominant response peak at about 225 nm with a cutoff wavelength at about 230 nm, which lies in the solar-blind spectrum range (220-280 nm). A shoulder also appeared in the response spectrum at about 265 nm besides the dominant peak, which resulted from the phase separation in the Mg0.70Zn0.30O thin films as revealed by transmission electron microscopy. The photodetector showed very low dark current (2 pA at 3 V bias). [ABSTRACT FROM AUTHOR]

Background: There are limited data on the relationship of ST-segment-elevation myocardial infarction (STEMI) management strategy and in-hospital cardiac arrest (IHCA)., Aims: To investigate the trends and outcomes of IHCA in STEMI by management strategy., Methods: Adult with STEMI complicated by IHCA from the National Inpatient Sample (2000-2017) were stratified into early percutaneous coronary intervention (PCI) (day 0 of hospitalization), delayed PCI (PCI ≥ day 1), or medical management (no PCI). Coronary artery bypass surgery was excluded. Outcomes of interest included in-hospital mortality, adverse events, length of stay, and hospitalization costs., Results: Of 3,967,711 STEMI admissions, IHCA was noted in 102,424 (2.6%) with an increase in incidence during this study period. Medically managed STEMI had higher rates of IHCA (3.6% vs 2.0% vs 1.3%, p < 0.001) compared to early and delayed PCI, respectively. Revascularization was associated with lower rates of IHCA (early PCI: adjusted odds ratio [aOR] 0.44 [95% confidence interval (CI) 0.43-0.44], p < 0.001; delayed PCI aOR 0.33 [95% CI 0.32-0.33], p < 0.001) compared to medical management. Non-revascularized patients had higher rates of non-shockable rhythms (62% vs 35% and 42.6%), but lower rates of multiorgan damage (44% vs 52.7% and 55.6%), cardiogenic shock (28% vs 65% and 57.4%) compared to early and delayed PCI, respectively (all p < 0.001). In-hospital mortality was lower with early PCI (49%, aOR 0.18, 95% CI 0.17-0.18), and delayed PCI (50.9%, aOR 0.18, 95% CI 0.17-0.19) (p < 0.001) compared to medical management (82.5%)., Conclusion: Early PCI in STEMI impacts the natural history of IHCA including timing and type of IHCA., (Copyright © 2023 Elsevier B.V. All rights reserved.)