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基于质谱的脂质C=C和脂肪酰基位置鉴定方法及其在食品分析中的应用研究进展

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食品科学 2025年第1期46卷 293-303页

作者：滕蒙南段晓亮张东郭伟群浙江农林大学食品与健康学院浙江杭州311302 国家粮食和物资储备局科学研究院北京102629

脂质在生命体中发挥着重要作用,结构影响功能,脂质精细结构解析至关重要。但脂质结构的多样性和相似性对脂质分析提出了巨大挑战。质谱是脂质分析的重要技术之一,在脂质C=C和脂肪酰基位置结构解析中有着较好的应用。本文介绍脂质分析的... 详细信息

脂质在生命体中发挥着重要作用,结构影响功能,脂质精细结构解析至关重要。但脂质结构的多样性和相似性对脂质分析提出了巨大挑战。质谱是脂质分析的重要技术之一,在脂质C=C和脂肪酰基位置结构解析中有着较好的应用。本文介绍脂质分析的前处理方法,综述基于质谱的C=C位置和脂肪酰基位置鉴定方法,并讨论该方法在食品分析中的应用,最后展望质谱在脂质化合物精确结构解析方面的发展趋势,以期为不饱和脂质C=C位置和脂肪酰基位置鉴定以及异构体识别和定量分析技术发展和应用提供参考。

关键词：脂质质谱 C=C位置脂肪酰基位置应用

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虚拟数字人对用户在线学习效果的影响研究

现代情报 2025年第1期45卷 81-96页

作者：赵一鸣郑乔治沈校亮武汉大学信息资源研究中心湖北武汉430072 武汉大学信息管理学院湖北武汉430072 武汉大学大数据研究院湖北武汉430072 武汉大学图书情报国家级实验教学示范中心湖北武汉430072

[目的/意义]在教学环境中使用虚拟数字人进行授课可以促使用户更高效地在线学习。本研究旨在探究在线学习中虚拟数字人特征对用户在线学习效果的影响,为在线教学视频设计和教学策略优化提供参考。[方法/过程]结合准社会互动理论,使用VTu... 详细信息

[目的/意义]在教学环境中使用虚拟数字人进行授课可以促使用户更高效地在线学习。本研究旨在探究在线学习中虚拟数字人特征对用户在线学习效果的影响,为在线教学视频设计和教学策略优化提供参考。[方法/过程]结合准社会互动理论,使用VTube Studio软件设计虚拟数字人教学的视频材料,招募用户观看教学视频并测量用户的主观感受,对在线学习中虚拟教师授课的情境进行探究。[结果/结论]虚拟数字人的吸引力、拟人化特征通过用户对虚拟数字人的态度和学习满意度的链式中介作用积极影响在线学习效果,拟人化到学习效果的中介路径之间存在遮掩效应;准社会互动对学习满意度有积极影响,而对学习效果存在负面作用。

关键词：虚拟数字人虚拟人虚拟教师学习效果准社会互动

A new solver for granular avalanche simulation： Indoor experiment verification and field scale case study

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Science China(Physics,Mechanics & Astronomy) 2017年第12期60卷 45-55页

作者： xiaoliang Wang JiaChun Li Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China School of Engineering Science University of Chinese Academy of Sciences Beijing 100049 China

A new solver based on the high-resolution scheme with novel treatments of source terms and interface capture for the Savage-Hutter model is developed to simulate granular avalanche flows. The capability to simulate flow spread and deposit processes is verified through indoor experiments of a two-dimensional granular avalanche. Parameter studies show that reduction in bed friction enhances runout efficiency, and that lower earth pressure restraints enlarge the deposit spread. The April 9, 2000,Yigong avalanche in Tibet, China, is simulated as a case study by this new solver. The predicted results, including evolution process, deposit spread, and hazard impacts, generally agree with site observations. It is concluded that the new solver for the Savage-Hutter equation provides a comprehensive software platform for granular avalanche simulation at both experimental and field scales. In particular, the solver can be a valuable tool for providing necessary information for hazard forecasts, disaster mitigation, and countermeasure decisions in mountainous areas.

关键词： avalanche landslide WAF TVD

Propulsive Characteristics of Twin Oscillating Airfoils

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Journal of Bionic Engineering 2016年第3期13卷 468-477页

作者： xiaoliang Wang Binbin Xuan School of Aeronautics and Astronautics Shanghai Jiao Tong University Shanghai 200240 China

The bionic propulsion can be used on the aerostat and other automatic vehicles. The general single oscillating tail fin can induce the yawing and whole airship rolling because of the lateral force and the gravity moment of heavier oscillating tail fin. The parallel twin oscillating tail fins by symmetrical swing mode can eliminate the lateral force and gravity moment through the symmetrical swing of the two tail fins. The propulsive characteristics of parallel twin fins have not been investigated up to now. In this paper, we investigated the propulsive characteristics and mechanism of parallel twin oscillating airfoils using consistent and symmetrical swing mode. By using the numerical calculation and analysis, the consistent swing mode may decrease the total propulsion efficiency. While, the symmetrical swing mode can improve the propulsion efficiency and reduce the lateral force and gravity moment. This mode can be used to propel the aerostat and automatic underwater vehicles efficiently.

关键词： propulsive characteristics oscillating airfoils bionic propulsion Computational Fluid Dynamics (CFD) swingmode ground effect

Horn–Schunck optical flow applied to deformation measurement of a birdlike airfoil

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Chinese Journal of Aeronautics 2015年第5期28卷 1305-1315页

作者： Gong xiaoliang Stephan Bansmer School of Aeronautics Northwestern Polytechnical University Institute of Fluid Mechanics Technische Universitt Braunschweig

Current deformation measurement techniques suffer from limited spatial resolution. In this work, a highly accurate and high-resolution Horn Schunck optical flow method is developed and then applied to measuring the static deformation of a birdlike flexible airfoil at a series of angles of attack at Reynolds number 100,000 in a low speed, low noise wind tunnel. To allow relatively large displacements, a nonlinear Horn-Schunck model and a coarse-to-fine warping process are adopted. To preserve optical flow discontinuities, a nonquadratic penalization function, a multi- cue driven bilateral filtering and a principle component analysis of local image patterns are used. First, the accuracy and convergence of this Horn-Schunck technique are verified on a benchmark. Then, the maximum displacement that can be reliably calculated by this technique is studied on synthetic images. Both studies are compared with the performance of a Lucas-Kanade optical flow method. Finally, the Horn-Schunck technique is used to estimate the 3-D deformation of the birdlike airfoil through a stereoscopic camera setup. The results are compared with those computed by Lucas-Kanade optical flow, image correlation and numerical simulation.

关键词： Deformation measurementsFlexible airfoil Horn-Schunck Optical flow Stereoscopic

On the degradation of granular materials due to internal erosion

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Acta Mechanica Sinica 2015年第5期31卷 685-697页

作者： xiaoliang Wang Jiachun Li Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of Sciences

A new state-based elasto-plastic constitutive relationship along with the discrete element model is established to estimate the degradation of granular materials due to internal *** essential effects of internal erosion such as the force network damage and relaxation are proposed and then incorporated into the constitutive relationship to formulate internal erosion impacts on the mechanical behavior of granular *** manifestations in the degradation of granular materials,such as reduction of peak strength and dilatancy are predicted by the modified constitutive relationship in good agreement with the discrete element method（DEM）*** particular,the sudden reduction of stress for conspicuous mass erosion in a high stress state is captured by force network damage and the relaxation *** is concluded that the new modified constitutive relationship is a potential theory to describe the degradation of granular materials due to internal erosion and would be very useful,for instance,in the prediction and assessment of piping disaster risk during the flood season.

关键词： Internal erosion Degradation Granular materials Discrete element method

A Discussion on Two Stochastic Elliptic Modeling Strategies

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Communications in Computational Physics 2012年第3期11卷 775-796页

作者： xiaoliang Wan Department of Mathematics and Center for Computation and Technology Louisiana State UniversityBaton RougeLA 70803USA

Based on the study of two commonly used stochastic elliptic models:I:−∇·(a(x,w)·∇u(x,w))=f(x)and II:−∇·(a(x,w)⋄∇u(x,w))=f(x),we constructed a new stochastic elliptic model III:−∇·(a^(−1))^(⋄(−1))⋄∇u(x,w)=f(x),in[20].The difference between models I and II is twofold:a scaling factor induced by the way of applying theWick product and the regularization induced by theWick product ***[20],we showed that model III has the same scaling factor as model *** this paper we present a detailed discussion about the difference between models I and III with respect to the two characteristic parameters of the random coefficient,i.e.,the standard deviation s and the correlation length *** results are presented for both one-and twodimensional cases.

关键词： Wiener chaos stochastic PDE stochastic modeling stochastic finite element method

Association of Nurr1 gene mutations with Parkinson's disease in the Han population living in the Hubei province of China

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Neural Regeneration Research 2012年第23期7卷 1791-1796页

作者： xiaoliang Lou Weijing Liao Department of Rehabilitation Medicine Zhongnan HospitalWuhan UniversityWuhan 430071Hubei ProvinceChina Department of Neurology Fourth Affiliated HospitalNanchang UniversityNanchang 330003Jiangxi ProvinceChina

Nurr1 defects could in part underlie Parkinson’s disease pathogenesis,and Nurr1 gene polymorphism has been found in Caucasian patients with Parkinson’s *** this study,heteroduplex technology was applied to compare the DNA sequences of eight exons of Nurr1 among 200 sporadic Parkinson’s disease patients and 200 healthy controls in the Han population in the Hubei province,*** allele amplified from exon 3 of Nurr1 was polymorphic in five Parkinson’s disease patients（2.5%,5/200）,and two individuals had a polymorphic allele amplified from exon 2 （1%,2/200）.The anomalous electrophoresis fragment in exon 3 of Nurr1 gene contained a 709C/A missense mutation,and a polymorphic single nucleotide polymorphism at 388G/A was identified in exon *** with the control group,the Nurr1 gene expression level in the Parkinson’s disease group was decreased,and the Nurr1 gene expression levels in Parkinson’s disease patients carrying the polymorphisms at exons 2 and 3 were significantly *** data indicate that the single nucleotide polymorphism 388G/A in exon 2 and the 709C/A missense mutation in exon 3 of the Nurr1 gene in the Chinese population might affect the pathogenesis of Parkinson’s disease.

关键词： Nurr1 gene Parkinson’s disease gene mutations gene polymorphism pathogenesis neurode-generative disease neural regeneration

Properties, Phases and Microstructure of Microwave Sintered W-20Cu Composites from Spray Pyrolysis-continuous Reduction Processed Powders

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Journal of Wuhan University of Technology(Materials Science) 2012年第1期27卷 38-44页

作者： TAO Jianqin SHI xiaoliang State Key Laboratory of Advanced Technology for Materials Synthesis&Processing Wuhan University of TechnologyWuhan 430070 China School of Mechanical and Electronic Engineering Wuhan University of TechnologyWuhan 430070China

The effects of microwave sintering on the properties, phases and microstructure of W-2OCu alloy, using composite powder fabricated by spray pyrolysis-continuous reduction technology, were investigated. Compared with the conventional hot-press sintering, microwave sintering to W-2OCu composites could be achieved with lower sintering temperature and shorter sintering time. Furthermore, microwave sintered W-Cu composites with high densification, homogenous microstructure and excellent properties were obtained. Microwave sintering could also result in finer microstructures. ：~

关键词： W-2OCu composite powder spray pyrolysis-continuous reduction microwave sintefing