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Plastic bronchitis associated with Botrytis cinerea infection in a child:A case report

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World Journal of Clinical Cases 2020年第20期8卷 5019-5024页

作者： Yan-Ru Liu tao ai Department of Pediatric Respiratory Medicine Chengdu Women’s and Children’s Central HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengdu 611731Sichuan ProvinceChina

BACKGROUND Plastic bronchitis(PB)frequently occurs in children after the surgical repair of congenital cardiac defects or in the presence of inflammatory or allergic diseases of the *** epidemiological data of this condition are still *** SUMMARY A 5-year-old boy,with a clear medical history,presented to our hospital with persistent cough and pneumonia with segmental atelectasis on chest computerized *** showed no significant improvement after 1 wk of amoxicillin-clavulanate potassium *** casts were extracted using flexible *** examination of the dendritic cast confirmed the diagnosis of type I *** cinerea was detected by next-generation sequencing of the bronchoalveolar lavage *** the removal of the airway obstruction and fluconazole treatment,the patient recovered and was discharged 14 d after admission without the recurrence of *** Botrytis cinerea pneumonia should be considered in children with PB who still have prolonged cough and atelectasis after a regular course of antibiotic *** bronchoscopy and etiological examination should be performed in a timely manner to determine the diagnosis,clear the airway obstruction,and target etiological treatment.

关键词： Bronchial casts Botrytis cinerea Pneumonia Children Case report

Mass transfer area in a multi-stage high-speed disperser with split packing

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Chinese Journal of Chemical Engineering 2019年第4期27卷 772-780页

作者： tao ai Aslam M.Mudassar Ziqi Cai Zhengming Gao State Key Laboratory of Chemical Resource Engineering School of Chemical Engineering Beijing University of Chemical Technology Beijing 100029 China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Beijing 100029 China

In this study, the mean droplet diameter in the cavity zone and the total mass transfer area of a multi-stage highspeed disperser(HSD) reactor with different packing combinations were measured and evaluated. The effects of rotational speed and packing radius, as well as the packing ring radius and numbers, on the mean droplet diameter and the total mass transfer area were evaluated. A model was established to calculate the mass transfer area in the cavity zone in the HSD reactor, and it was found that the packings contribute 61%–82% of the total mass transfer area. A correlation for predicting the mass transfer area in the packing zone was regressed by the dimensionless analysis method. An enhancement factor based on the mass transfer area in the packing zone was proposed to evaluate the effect of packing combination on mass transfer area. Two optimum packing combinations were proposed in consideration of the mean droplet diameter and the enhancement factor.

关键词： High-speed disperser Mean droplet diameter Mass transfer area Split packing

Review on the Progress and Issues in Liquid Tank Sloshing of Ships

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China Ocean Engineering 2023年第5期37卷 709-724页

作者： ZHANG Zhen tao ai-feng WU Qiao-rui XIE Yong-he Key Laboratory of Ministry of Education for Coastal Disaster and Protection Hohai UniversityNanjing 210098China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China College of Naval Architecture and Maritime Zhejiang Ocean UniversityZhoushan 316022China

With the development of large liquid cargo ships,liquid tank sloshing has gradually become a hot research topic in the area of shipping and ocean *** tank sloshing,characterized by strong nonlinearity and randomness,not only affects the stability of the ship but also generates a huge impact force on the wall of the *** further investigate liquid tank sloshing,a comprehensive review is given on the research process of the most focused subjects of liquid *** the existing research will help to identify issues in the current field and provide useful *** methods for investigating sloshing,the research progress and the situations worldwide are *** advantages and defects of experiments and numerical simulations are also *** problems which need to be explored in the future are subsequently proposed.

关键词： naval architecture and marine engineering liquid tank sloshing liquid cargo ship large deformation progress review

Metastable magnetic behavior in La_(0.9)Tb_(0.1)MnO_3

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Rare Metals 2017年第7期36卷 596-600页

作者： Wei-Bin Liu Ying-Tang Zhang Zi-Yu Chen Li-Zhu Liu Sheng-tao Li tao-tao ai Department of Physics Beijing University of Aeronautics and Astronautics School of Material Science and Engineering Institute of Functional MaterialShaanxi University of Technology Key Laboratory of Engineering Dielectrics and Its Application Ministry of EducationHarbin University of Science and Technology State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong University

The linear and nonlinear magnetizations of La0.9Tb0.1MnO3 at low temperatures were reported in de- tail. The temperature dependence of magnetization shows peaks at 50, 100 and 150 K, respectively. When LaMnO3 is Tb-doped, its magnetic structure exhibits a canted an- tiparallel spin order. This is different from classical antiferromagnetic （AFM） in which the relaxation behavior takes place at about 150 K. At 50 K, Tb-doped LaMnO3 exhibits canonical spin glass behavior, arising from the competition of exchange and super-exchange between spins. The peak at 100 K shows neither spin glass behavior nor canted AFM behavior. Its peak value increases with frequency increasing, and the transition temperature of the peak shifts to higher temperatures with frequency increasing. The study of aging behavior at 100 K shows a periodical variable metastability, which is ascribed to the competition between ferromagnetic （FM）-, AFM- and sinusoidal-order interactions. This work should shed a light on understanding the complex magnetic structure of the perovskite oxides.

关键词： La0.9Tb0.1MnO3 Relaxation behavior Metastability

Flume Experiment Investigation on Propagation Characteristics of Tidal Bore in A Curved Channel

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China Ocean Engineering 2023年第1期37卷 131-144页

作者： FAN Jun tao ai-feng SHI Mo-quan LI Ying PENG Ji Key Laboratory of Ministry of Education for Coastal Disaster and Protection Hohai UniversityNanjing 210098China College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210098China The Adminstrative Committee of Nantong Haimen Sanchang Industrial Park Nantong 226121China Zhejiang University of Water Resources and Electric Power Hangzhou 310018China China Renewable Energy Engineering Institute Beijing 100120China

Tidal bore is a special and intensive form of flow movement induced by tidal effect in estuary areas, which has complex characteristics of profile, propagation and flow velocity. Although it has been widely studied for the generation mechanism, propagation features and influencing factors, the curved channel will complicate the characteristics of tidal bore propagation, which need further investigation compared with straight channel. In this study, the flume experiments for both undular and breaking bores’ propagation in curved channel are performed to measure the freesurface elevation and flow velocity by ultrasonic sensors and ADV respectively. The propagation characteristics,including tidal bore height, cross-section surface gradient, tidal bore propagation celerity, and flow velocity are obtained for both sides of the curved channel. And three bore intensities are set for each type of tidal bores. The freesurface gradients are consistently enlarged in high-curvature section for undular and breaking bores, but have distinct behaviors in low-curvature section. The spatial distributions of tidal bore propagation celerity and flow velocity are compared between concave and convex banks. This work will provide experimental reference for engineering design of beach and seawall protection, erosion reduction and siltation promotion in estuary areas with the existence of tidal bores.

关键词： tidal bore curved channel flume experiment propagation celerity bore intensity

On the Downshift of Wave Frequency for Bragg Resonance

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China Ocean Engineering 2022年第1期36卷 76-85页

作者： PENG Ji tao ai-feng FAN Jun ZHENG Jin-hai LIU Yu-ming Key Laboratory of Ministry of Education for Coastal Disaster and Protection Hohai UniversityNanjing 210098China Quality Supervision Department China Renewable Energy Engineering InstituteBeijing 100120China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridge 02139USA

For surface gravity waves propagating over a horizontal bottom that consists of a patch of sinusoidal ripples,strong wave reflection occurs under the Bragg resonance *** critical wave frequency,at which the peak reflection coefficient is obtained,has been observed in both physical experiments and direct numerical simulations to be downshifted from the well-known theoretical *** has long been speculated that the downshift may be attributed to higher-order rippled bottom and free-surface boundary effects,but the intrinsic mechanism remains *** a regular perturbation analysis,we derive the theoretical solution of frequency downshift due to third-order nonlinear effects of both bottom and free-surface *** is found that the bottom nonlinearity plays the dominant role in frequency downshift while the free-surface nonlinearity actually causes frequency *** frequency downshift/upshift has a quadratic dependence in the bottom/free-surface *** bottom leads to a larger frequency downshift relative to the monochromatic *** addition,direct numerical simulations based on the high-order spectral method are conducted to validate the present *** theoretical solution of frequency downshift compares well with the numerical simulations and available experimental data.

关键词： gravity surface wave Bragg resonance frequency downshift regular perturbation analysis

Mechanical properties and energy absorption of extruded Mg–2.0Zn–0.3Zr alloy with Y addition

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Rare Metals 2015年第5期34卷 314-323页

作者： Bin-Jiang Lv Jian Peng Yi Peng ai-tao Tang Fu-Sheng Pan College of Materials Science and Engineering Chongqing University Chongqing Advanced Materials Research Center Chongqing Academy of Science and Technology

The effects of the rare earth element Y addition on mechanical properties and energy absorption of a low Zn content Mg-Zn-Zr system alloy and the deformation temperature of optimized alloy were investigated by room tensile test, optical microscopy （OM）, X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and transmission electron microscope （TEM）. The results show that, after homogenization at 420℃ for 12 h for the as-cast alloys, MgZn phase forms, which decreases the strength of Mg-2.0Zn-0.3Zr alloy with Y content of 0.9 wt%. The tensile strength and elongation of the alloy with a Y addition of 5.8 wt% reach the max value （281 ±2） MPa and （30.1 ± 0.7） %, respectively; the strength and elongation of Mg-2.0Zn-0.3Zr-0.9Y alloy at the optimized extrusion temperature of 330 ℃ reach （321 ± 1） MPa and （21.9 ± 0.7） %, respectively. The energy absorption increases with the increase of Y content, the max value reached 0.79 MJ·m^-3 with Y content of 5.8 wt%, and the energy absorption of Mg-2.0Zn-0.3Zr-0.9Y alloy at the optimized extrusion temperature of 330 ℃ reaches 0.75 MJ·m^-3.

关键词： Yttrium Microstructure Mechanical properties Energy absorption

Effects of Sb Addition on Microstructural Evolution and Mechanical Properties of Mg–9Al–5Sn Alloy

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Acta Metallurgica Sinica(English Letters) 2021年第2期34卷 278-288页

作者： Chun-Hua Ma Fu-Sheng Pan Ding-Fei Zhang ai-tao Tang Zhi-Wen Lu College of Materials Science and Engineering Chongqing UniversityChongqing 400045China College of Mechanical and Electronic Engineering Nanyang Normal UniversityNanyang 473061China

The Mg–9Al–5Sn-xSb(x=0.0,0.3,0.6,1.0,1.5 wt%)alloys were prepared by a simple alloying process followed by hot extrusion with an extrusion ratio of *** effects of Sb additions on the microstructure and mechanical properties of the Mg–9 Al–5 Sn alloys were investigated by optical microscopy,X-ray diffraction,transmission electron microscopy,scanning electron microscopy equipped with an energy-dispersive X-ray *** results indicated that the phasesα-Mg matrix,Mg2Sn,Mg_(3)Sb_(2) and Mg17 Al12 exist in the as-cast Sb-containing *** addition results in the precipitation of Mg_(3)Sb_(2).The dendritic size of these alloys decreases with the addition of *** their ultimate tensile strength and yield strength of extruded alloys increase,and their elongation decreases gradually with increasing the content of *** better mechanical properties of the as-extruded alloys were achieved due to the refined grains and the formation of dispersive second phases Mg_(3)Sb_(2).

关键词： Mg–Al–Sn–Sb alloy Microstructure Extrusion Second phase Mechanical properties

Wave Power Focusing due to the Bragg Resonance

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China Ocean Engineering 2017年第4期31卷 458-465页

作者： tao ai-feng YAN Jin WANG Yi ZHENG Jin-hai FAN Jun QIN Chuan State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China College of Harbor Coastal and Offshore Engineering Hohai University Nanjing 210098 China College of Energy and Electrical Engineering Hohai University Nanjing 210098 China

Wave energy has drawn much attention as an achievable way to exploit the renewable energy. At present, in order to enhance the wave energy extraction, most efforts have been concentrated on optimizing the wave energy convertor and the power take-off system mechanically and electrically. However, focusing the wave power in specific wave field could also be an alternative to improve the wave energy extraction. In this experimental study, the Bragg resonance effect is applied to focus the wave energy. Because the Bragg resonance effect of the rippled bottom largely amplifies the wave reflection, leading to a significant increase of wave focusing. Achieved with an energy conversion system consisting of a point absorber and a permanent magnet single phase linear motor, the wave energy extracted in the wave flume with and without Bragg resonance effect was measured and compared quantitatively in experiment. It shows that energy extraction by a point absorber from a standing wave field resulted from Bragg resonance effect can be remarkably increased compared with that from a propagating wave field （without Bragg resonance effect）.

关键词： wave power experiment Bragg resonance