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Design and Experimental Verification of a Roll Control Strategy for Large Wingspan Flapping-Wing Aerial Vehicle

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Journal of Bionic Engineering 2024年第4期21卷 1644-1661页

作者： Rui Meng Bifeng Song Jianlin xuan Xiaojun Yang Dong xue School of Aeronautics Northwestern Polytechnical UniversityXi’an710072China Research and Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen518057China Yangtze River Delta Research Institute of Northwestern Polytechnical University Taicang215400China

Most flapping-wing aircraft wings use a single degree of freedom to generate lift and thrust by flapping up and down,while relying on the tail control surfaces to manage ***,these aircraft have certain limitations,such as poor accuracy in attitude control and inadequate roll control *** paper presents a design for an active torsional mechanism at the wing's trailing edge,which enables differential variations in the pitch angle of the left and right wings during *** simple mechanical form significantly enhances the aircraft's roll control *** experimental verification of this mechanism was conducted in a wind tunnel using the RoboEagle flapping-wing aerial vehicle that we *** study investigated the effects of the control strategy on lift,thrust,and roll moment during flapping ***,the impact of roll control on roll moment was examined under various wind speeds,flapping frequencies,angles of attack,and wing ***,several rolling maneuver flight tests were performed to evaluate the agility of RoboEagle,utilizing both the elevon control strategy and the new roll control *** results demonstrated that the new roll control strategy effectively enhances the roll control capability,thereby improving the attitude control capabilities of the flapping-wing aircraft in complex wind field *** conclusion is supported by a comparison of the control time,maximum roll angle,average roll angular velocity,and other relevant parameters between the two control strategies under identical roll control input.

关键词： Roll control Bio-inspired Roll moment Flapping wing aerial vehicle

Numerical Studies on the Generation and Propagation of Tsunami Waves Based on the High-Order Spectral Method

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China Ocean Engineering 2022年第2期36卷 268-278页

作者： HAO Jian LI Jin-xuan LIU Shu-xue WANG Lei State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

An effective numerical model for wave propagation over three-dimensional(3D)bathymetry was developed based on the High-Order Spectral(HOS)method and combined with a moving bottom *** on this model,tsunami waves caused by various mechanisms were simulated and ***-dimensional bed upthrust and the effect of the uplift velocity of the bathymetry on the wave profiles of tsunami waves were ***,tsunami waves caused by 3D submarine slides were generated and the effects of the slide velocity,slide dimension and water depth on the tsunami waves were *** on wavelet analysis,the properties of the tsunami wave propagation were *** results show that the bottom movement can significantly affect the generation and propagation of tsunami waves and the studies could help understand the mechanisms of tsunamis caused by a moving bottom boundary.

关键词： tsunami waves High-Order Spectral(HOS)method moving bottom boundary wavelet analysis

Visible light-mediated C—P bond formation reactions

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Science Bulletin 2019年第5期64卷 337-350页

作者： Bao-Gui Cai Jun xuan wen-Jing Xiao Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials College of Chemistry & Chemical Engineering Anhui University Key Laboratory of Pesticide & Chemical Biology Ministry of Education College of Chemistry Central China Normal University

Organophosphorus compounds have attracted continuous attention in materials science, agrochemical and pharmaceutical fields due to their unique bioactivities. Thus, the development of novel and robust manners for the construction new C—P bond has therefore gained great interests in synthetic organic chemistry. Because of their intrinsic sustainability and green chemistry character, visible light-induced photoredox catalysis has been widely applied in the construction of new chemical bonds, including the formation of C—P bond. In this review, we summarized recent achievements in C—P bond formation reactions initiated by visible light-induced photoredox catalysis, which mainly focusing on the discussion of reaction design and the mechanism.

关键词： C-P bond formation Organophosphorus compounds Photoredox catalysis Visible light

Rehabilitation of anterior pituitary dysfunction combined with extrapontine myelinolysis: A case report

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World Journal of Clinical Cases 2019年第24期7卷 4420-4425页

作者： Ming-xuan Yang xue-Nong Chen Department of Rehabilitation Affiliated Hospital of Zunyi Medical University

BACKGROUND Extramedullary myelinolysis is a rare demyelinating disease, often caused by rapid increases in serum sodium concentration in patients with *** manifestations are neuropsychiatric symptoms, limb weakness, and dysarthria. Because of its poor prognosis and high disability rate, it poses a huge burden on the global economy, societies, and families. This article reports rehabilitation in a patient with pituitary dysfunction combined with extramedullary *** SUMMARY A 27-year-old Chinese man developed anorexia, vomiting, and limb weakness and was diagnosed with pituitary insufficiency. He had low serum sodium, slow movement, muscle weakness, and muscle tone abnormalities after sodium supplementation, involuntary limb shaking, ataxia, and dysarthria. According to the symptoms and signs and imaging reports, he was diagnosed with extramedullary myelinolysis. After treatment with hormone therapy and neurotrophic drugs, motor and speech function did not improve, so he was treated in the rehabilitation department for 4 wk. The patient's physical status was improved substantially during his stay at the rehabilitation *** Patients with extramedullary myelinolysis who actively participate in rehabilitation intervention can significantly improve their activities of daily living.

关键词： Anterior pituitary dysfunction Extrapontine myelinolysis Rehabilitation Motor function Speech function Case report

Investigation of the entropy generation and efficiency of a solar thermophotovoltaic system

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Chinese Science Bulletin 2010年第32期55卷 3718-3726页

作者： CHEN xue xuan YiMin HAN YuGe School of Power Engineering Nanjing University of Science and Technology Nanjing 210094 China

Based on the second law of thermodynamics,a theoretical model is established for efficiency analysis and optimization of a solar thermophotovoltaic (STPV) system. The entropy generation in the photo-electricity conversion process is numerically calculated and analyzed for the component modules involved in the whole system assembly. The effects of the emitter temperature,concentration ratio,energy bandgap,cell temperature and the transmissivity of the filter on the entropy and the efficiency are investigated. Meanwhile,the conversion efficiencies of the modules are discussed. The following results are obtained:at first the entropy generation of the system reduces but then increases with the rise of the emitter temperature. When the concentration ratio improves,the entropy generation of the system falls. The increase of the bandgap value and chemical potential of the cell also causes the reduction of the entropy generation. Along with the increase of the cell temperature,the entropy generation increases and the conversion efficiency of the STPV system decreases.

关键词：光电系统熵产生太阳能热力学第二定律电池温度分析模块转换效率模型分析

Synthesis of Helical Poly(phenylacetylene)s Carrying Dendritic Pendants with Varied Branching Densities Through Polymerization in Different Solvents

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Chinese Journal of Polymer Science 2023年第10期41卷 1543-1554页

作者： Zhen-Zhen Sun Yan-Ning Zhang Hao-Yu Qiu xue-Ting Lu Liang-xuan Ren Le-Fei Shen wen Li Afang Zhang International Joint Laboratory of Biomimetic and Smart Polymers School of Materials Science and EngineeringShanghai UniversityShanghai200444China

Helical poly(phenylacetylene)s(PPAs)have received extensive attention because of their features in dynamic chirality and promising ***,understanding relationship among the polymer molecular structures,polymerization conditions and tunability of their chirality is of key scientific ***,we developed a novel class of dendronized PPAs carrying 3-fold dendritic oligo(ethylene glycols)(OEGs)via alanine linkage,and found that these bulky polymers exhibited tunable helical conformations through thermally-mediated dehydration and ***,we report on synthesis of a homologous series of dendronized PPAs that carry 2-fold,3-fold or 6-fold dendritic OEG pendants,and focus on effects of molecular topological structures,peripheral units and polymerization solvents on the thermoresponsiveness and their conformation switching *** of branching density and peripheral units(ethoxyl or methoxyl)of the dendritic OEG pendants were examined,and found to play a decisive role on the helical conformation and thermoresponsiveness of these dendronized PPAs due to their different bulkiness and overall *** addition,different polymerization solvents were checked for their possible influence on the polymerization,thermoresponsive behavior and the chirality of the resulting *** polymerization in selective solvents like water or methanol,the obtained dendronized PPAs exhibited weak thermal transitions,while polymerization in non-selective solvent like THF furnished PPAs with characteristic thermoresponsive behavior,indicating that solvents were involved in the process of polymerization of the dendronized *** interestingly,different chiralities of the PPAs through polymerization in various solvents were retained,irrelevant to the purification process and solvents *** work suggests that the topological structures together with polymerization solvents can modulate the thermoresponsive behavior and h

关键词： Helical polymer Dendronized polymer Thermores ponsive polymer Solvation Dendritic oligoethylene glycol

Contrasting Magnetism in Isovalent Layered LaSr3NiRuO4H4 and LaSrNiRuO4 due to Distinct Spin-Orbital States

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Chinese Physics Letters 2019年第7期36卷 98-102页

作者： xuan wen Ke Yang Hua Wu Laboratory for Computational Physical Sciences (MOE) State Key Laboratory of Surface Physics and Department of Physics Fudan University Shanghai 200433 Collaborative Innovation Center of Advanced Microstructures Nanjing 210093

The recently synthesized first 4d transition-metal oxide-hydride LaSr3NiRuO4H4 with the unusual high H:O ratio surprisingly displays no magnetic order down to 1.8 K. This is in sharp contrast to the similar unusual low-valent Ni^+-Ru^2+ layered oxide LaSrNiRuO4 which has a rather high ferromagnetic(FM) ordering Curie temperature TC^250 K. Using density functional calculations with the aid of crystal field level diagrams and superexchange pictures, we find that the contrasting magnetism is due to the distinct spin-orbital states of the Ru^2+ions(in addition to the common Ni+S = 1/2 state but with a different orbital state): the Ru^2+S = 0 state in LaSr3NiRuO4H4, but the Ru^2+S= 1 state in LaSrNiRuO4. The Ru^2+S = 0 state has the(xy)^2(xz, yz)^4 occupation due to the RuH4O2 octahedral coordination, and then the nonmagnetic Ru2+ions dilute the S= 1/2 Ni^+ sublattice which consequently has a very weak antiferromagnetic superexchange and thus accounts for the presence of no magnetic order down to 1.8 K in LaSr3NiRuO4H4. In strong contrast, the Ru^2+S = 1 state in LaSrNiRuO4 has the(3z^2-r^2)^2(xz, yz)^3(xy)^1 occupation due to the planar square RuO4 coordination, and then the multi-orbital FM superexchange between the S= 1/2 Ni^+ and S= 1 Ru^2+ions gives rise to the high TC in LaSrNiRuO4. This work highlights the importance of spin-orbital states in determining the distinct magnetism.

关键词： The recently synthesized LaSr3NiRuO4H4

Enhanced air filtration performance under high-humidity condition through electrospun membranes with optimized structure

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Chinese Journal of Chemical Engineering 2020年第7期28卷 1788-1795页

作者： xue Gao Sisi wen Bingling Yang Jian xue Haihui Wang School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640China State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhou 510640China

The separation stability under high-humidity is significant in practical applications for air ***,hydrophobic polyvinyl chloride(PVC)nanofiber filters with bead-on-string structure are designed to steadily remove particle matter under high relative humidity of 90%-95%.The developed hydrophobic filters possess comparable separation performance with the hydrophilic one,but greatly enhanced *** the introduction of beadon-string structure,the filtration performance can be furtherly improved due to the formed large cavities and *** hydrophobic PVC filters can be promising candidates for air purification in practical applications especially in wet seasons.

关键词： Bead-on-string structure Electrospun membranes High humidity Air purification

Miocene paleoenvironmental evolution based on benthic foraminiferal assemblages in the Lufeng Sag, northern South China Sea

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Acta Oceanologica Sinica 2019年第3期38卷 124-137页

作者： Liyuan xue xuan Ding Renjie Pei Xiaoqiao Wan School of Ocean Sciences China University of Geosciences School of Earth Sciences and Resources China University of Geosciences

The Miocene epoch marks the most crucial period during the Cenozoic cooling trend, characterized by the Middle Miocene Climatic Optimum(MMCO) and a series of short–lived cooling events(Miocene isotope events).To understand the paleoenvironmental evolution along the shallow water shelf in the South China Sea during the Miocene, the benthic foraminiferal assemblage and total organic carbon content(TOC) were analyzed at Hole LF14 located in the Lufeng Sag, northern South China Sea. Three benthic foraminiferal assemblages(e.g., the Uvigerina spp. assemblage, the Cibicides spp. assemblage, and the Cibicidoides spp. assemblage), corresponding to different watermass conditions, were recognized based on Q–mode factor analysis. Early studies suggested that Hole LF14 was deposited under semienclosed bay, middle to outer shelf or even upper bathyal environment during ～18.7–4.53 Ma. The dominant Uvigerina spp. assemblage was characterized by low diversity and shallow infaunal to infaunal species, indicating a warm, low–oxygenation and eutrophic conditions since the Early Miocene to MMCO(～18.7–14.24 Ma). An abrupt sea level drop and significant faunal changes were recorded during 14.24–13.41 Ma, suggesting development of the East Antarctic Ice Sheets, which resulted in a drop of sea level and change in benthic foraminiferal assemblages along the shallow water shelf. Beyond the Uvigerina ***, the Cibicides spp. assemblage became important during the middle–late Middle Miocene(14.24–11.54 Ma). This assemblage was dominated by epifaunal species with relative high diversity, suggesting high–energy, high–oxygenation and oligotrophic conditions with episodic supply of organic food. The dominant Cibicidoides spp. assemblage with high diversity, indicates a mesotrophic conditions with relative high–oxygen content during the Late Miocene to Pliocene(11.54–4.53 Ma). The appearance and continuous occurrence of Ammonia spp. and Pseudorotalia spp. since 10.02 Ma, may reflect the i

关键词： South China Sea Lufeng Sag Miocene benthic foraminiferal assemblage total organic carbon shelf paleoenvironment