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With the implementation of strict emission regulations and the use of cleaner fuels, there has been a considerable reduction in exhaust emissions. However, the relative contribution of tire wear particles (TWPs) to particulate matters is expected to gradually increase. This study conducted laboratory wear experiments on tires equipped on domestically popular vehicle models, testing the factors and particle size distribution of TWPs. The results showed that the content of tire wear particle emission was mainly ultrafine particles, accounting for 94.80% of particles ranging from 6 nm to 10 μm. There were at least two concentration peaks for each test condition and sample, at 10~13 nm and 23~41 nm, respectively. The mass of TWP emission was mainly composed of fine particles and coarse particles, with concentration peaks at 0.5 μm and 1.3–2.5 μm, respectively. Both the number and mass of TWPs exhibited a bimodal distribution, with significant differences in emission intensity among different tire samples. However, there was a good exponential relationship between PM10 mass emissions from tire wear and tire camber angle. The orthogonal experimental results showed that the slip angle showed the greatest impact on TWP emission, followed by speed and load, with the smallest impact from inclination angle. [ABSTRACT FROM AUTHOR]

In this work, we draw connections between the imaging conditions using the impedance kernel, the inverse scattering imaging condition, and the energy norm imaging condition in acoustic and elastic reverse-time migration (RTM). Traditional RTM often introduces large low-wavenumber artifacts that degrade image quality in intricate geological structures with large velocity variations. In practice, the Laplacian filter is commonly used to remove these low-wavenumber artifacts, but it changes the image wavenumber spectrum. The advanced imaging conditions of the inverse scattering, the energy norm, and the impedance kernel can effectively remove the low-wavenumber artifacts while not changing the wavenumber spectrum. This study aims to build a connection between these three types of imaging conditions by conducting detailed analysis in the wavenumber domain for acoustic and elastic RTMs. We find that they are exactly the same except for the varying weights of the source-receiver wavefield cross-correlation. All three imaging conditions can generate clear RTM images that are not affected by low-wavenumber artifacts. Numerical examples for a simple model, Sigsbee 2a, and BP models verify the consistency of these three imaging conditions and show their advantage over conventional simple zero-lag cross-correlation imaging conditions. This is important for improving the quality and reliability of seismic imaging technology. [ABSTRACT FROM AUTHOR]

Introduction: Targeting the parasympathetic nervous system innervating the airway with pharmacologic products has been proved to improve the clinical outcomes of severe asthma. Bronchial cryo-denervation (BCD) is a novel non-pharmacologic treatment for severe asthma using an endobronchial cryo-balloon administered via bronchoscopy to denervate parasympathetic pulmonary nerves. Preclinical studies have demonstrated that BCD significantly disrupted vagal innervation in the lung. Methods: A total of 15 patients with severe asthma were enrolled in this prospective, single-center pilot study. Patients underwent bifurcated BCD treatment at a 30-day interval after baseline assessment. Follow-up through 12 months included assessment of adverse events, technical feasibility, and changes in pulmonary function; asthma control questionnaire-7 (ACQ-7); and asthma control test (ACT). Results: BCD was performed on all 15 severe asthma patients, with technical feasibility of 96.7%. There were no device-related and 2 procedure-related serious adverse events through 12 months, which resolved without sequelae. The most frequent nonserious procedure-related adverse event was increased cough in 60% (9 of 15) patients. Pulmonary function remained unchanged, and significant improvements from baseline ACQ-7 (mean, −1.19, p = 0.0032) and ACT (mean, 3.18, p = 0.0011) scores were observed since the first month's follow-up after a single lung airway treatment, with similar trends till the end of the 12-month follow-up. Conclusion: This study provides the first clinical evidence of the safety, feasibility, and initial efficacy of BCD in patients with severe asthma. [ABSTRACT FROM AUTHOR]

In order to improve the energy-saving effect of a pure electric vehicle, this paper analyzes the causes and influencing factors of the internal resistance loss of the automobile, and expounds the necessity of internal resistance optimization. Select a model in research and development, determine the resistance through the sliding resistance test, and evaluate the energy saving potential of the vehicle through the benchmarking method. A method of resistance decomposition is proposed. The resistance values of key components are tested and analyzed, and the optimization scheme is given. In order to verify the effect of the optimization scheme, this paper proposes a theoretical calculation method. After verification, the proposed optimization scheme finally improves the energy-saving effect of the vehicle by 3%.

In order to study the gasoline working capacity and durability of the carbon canister, the gasoline working capacity test of the carbon canister was conducted under different test conditions. The results showed that the gasoline working capacity of the canister carbon decreased with the increase of fuel vapor loading rate. The fuel vapor volume ratio of the inlet has little effect on the gasoline working capacity. After 300 gasoline working capacity test cycles, the working capacity of butane decreased by about 20%. The fuel vapor adsorption amount in first cycle of each carbon canister is far greater than the desorption amount in first cycle, and also far greater than the adsorption and desorption amount in the subsequent cycles, which indicated that a large amount of fuel vapor occupied the active sites after the first use of the carbon canister and cannot desorb.

The aging of population is a worldwide social problem that all countries will face in the 21st century. The health and quality of life of the elderly will have a significant impact on the country and society. In fact, falls are the leading cause of accidental injury or death in the elderly. Fortunately, using inflatable airbags as a buffer to reduce the injuries caused by falls is currently the most effective means of fall protection. This paper designs an indoor protection device for elderly patients in the rehabilitation stage. It not only includes an accurate and effective fall detection system, but also can use airbags and mechanical exoskeleton to perform head, waist and hip joints on patients who are about to fall. Through experiments, the designed airbag can be ejected within a specified time, and the designed algorithm can accurately distinguish the fall of the human body from the daily behaviour of human body.

This paper briefly introduces the progress of evaporative emission standards for light-duty vehicles in developed countries such as the United States and Europe, and the test procedures specified in the latest evaporative emission standard were concluded. Moreover, the development of evaporative emission standards for light-duty vehicles in China was comparatively analyzed. The evaporative emission test data from 2004 to 2019 was randomly selected for analysis of the trend of evaporative emission performance of vehicles in China with the use of EPR. Affected by the more stringent China 6 Evaporative Emissions standards issued in 2016, the EPR value of the evaporative emission test conducted according to the China 5 had continuously decreased to 41% in 2018. Subsequently, the EPR value increased again to a value of 60% in 2018 and 2019 due to strengthen of the emission limit from 2g to 0.7g and the raise of deterioration factor. Finally, based on the world's latest evaporative emission standards, the development trend of evaporative emission standards for light-duty vehicles in China is forecasted. The application of canister bench aging test, BETP, running loss emission test, and a test cycle with Chinese characteristics may be more conducive to control the light-duty vehicle emissions. Compared with the LEV 3, the evaporative emission limit of 0.7g/test specified in China 6 is still relatively larger. In addition, strengthen the control of durability test and in-use emission performance test would makes the HC emission less during the actual operation of the vehicle.

A series of Yttrium (Y)-doped Bi2MoO6 composites with calcined mussel shell powder (CMS) as supports were synthesized using a solvothermal method. The as-prepared samples were analyzed using multiple techniques to investigate their microscopic morphology, composition structure, and optical properties. The photocatalytic performance of the as-prepared samples was assessed via examining their capacity to degrade Rhodamine B (RhB) under visible-light irradiation. The photocatalytic data showed that the Y-doped Bi2MoO6/CMS composites exhibited better photocatalytic activity compared to pure Bi2MoO6 and undoped Bi2MoO6/CMS samples. Among the samples, the 0.5%Y-doped Bi2MoO6/CMS (0.5%Y-BC) showed the highest photocatalytic activity, achieving a maximum degradation rate of 99.7% within 60 min. This could be attributed to highly reactive sites due to Y doping, a narrower band gap, and a lower recombination rate of photoinduced electron–hole pairs. Additionally, the 0.5%Y-BC photocatalyst exhibited excellent stability and reusability properties even after four cycles, making it suitable for practical applications. The findings provided a feasible synthesis of nanocomposite photocatalysts with outstanding properties for organic pollutant removal from the solution system. [ABSTRACT FROM AUTHOR]