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Chinese Physics B 2020年第12期29卷 93-98页

作者： Jun Liu hua tong Yunhuan Nie Ning Xu Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Microscale Magnetic Resonanceand Department of PhysicsUniversity of Science and Technology of ChinaHefei 230026China School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China

In marginally jammed solids confined by walls,we calculate the particle and ensemble averaged value of an order parameter,Ψ(r),as a function of the distance to the wall,*** a microscopic indicator of structural disorder and particle mobility in solids,Ψis by definition the response of the mean square particle displacement to the increase of temperature in the harmonic approximation and can be directly calculated from the normal modes of vibration of the zerotemperature *** find that,in confined jammed solids,Ψ(r)curves at different pressures can collapse onto the same master curve following a scaling function,indicating the criticality of the jamming *** scaling collapse suggests a diverging length scale and marginal instability at the jamming transition,which should be accessible to sophisticatedly designed ***,Ψ(r)is found to be significantly suppressed when approaching the wall and anisotropic in directions perpendicular and parallel to the *** finding can be applied to understand the r-dependence and anisotropy of the structural relaxation in confined supercooled liquids,providing another example of understanding or predicting behaviors of supercooled liquids from the perspective of the zero-temperature amorphous solids.

关键词： jamming transition supercooled liquids amorphous solids criticality

Optimizing loading path and die linetype of large length-to-diameter ratio metal stator screw lining hydroforming

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Journal of Central South University 2015年第1期22卷 224-231页

作者：祝效华石昌帅童华 Mechatronic Engineering College Southwest Petroleum University

In order to meet the high temperature environment requirement of deep and superdeep well exploitation, a technology of large length-to-diameter ratio metal stator screw lining meshing with rotor is presented. Based on the elastic-plasticity theory, and under the consideration of the effect of tube size, material mechanical parameters, friction coefficient and loading paths, the external pressure plastic forming mechanical model of metal stator screw lining is established, to study the optimal loading path of metal stator lining tube hydroforming process. The results show that wall thickness reduction of the external pressure tube hydroforming(THF) is about 4%, and three evaluation criteria of metal stator screw lining forming quality are presented: fillet stick mold coefficient, thickness relative error and forming quality coefficient. The smaller the three criteria are, the better the forming quality *** indicator has a trend of increase with the loading rate reducing, and the adjustment laws of die arc transition zone equidistance profile curve are acquired for improving tube forming quality. Hence, the research results prove the feasibility of external pressure THF used for processing high-accuracy large length-to-diameter ratio metal stator screw lining, and provide theoretical basis for designing new kind of stator structure which has better performance and longer service life.

关键词： tube hydroforming loading path large length-to-diameter ratio metal stator lining simulation

Role of disorder in determining the vibrational properties of mass-spring networks

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Frontiers of physics 2017年第3期12卷 175-185页

作者： Yunhuan Nie hua tong Jun Liu Mengjie Zu Ning Xu CAS Key Laboratory of Soft Matter Chemistry Hefei National Laboratory for Physical Sciences at the Micrascale and Department of Physics University of Science and Technology of China Hefei 230026 China Institute of Industrial Science University of Tokyo Meguro-ku Tokyo 153-8505 Japan

By introducing four fundamental types of disorders into a two-dimensional triangular lattice separately, we determine the role of each type of disorder in the vibration of the resulting mass-spring networks. We are concerned mainly with the origin of the boson peak and the connection between the boson peak and the transverse Ioffe-Regel limit. For all types of disorders, we observe the emergence of the boson peak and Ioffe-Regel limits. With increasing disorder, the boson peak frequency ωBP, transverse Ioffe-Regel frequency ω^TIR, and longitudinal Ioffe-Regel frequency wLn all decrease. We find that there are two ways for the boson peak to form： developing from and coexisting with （but remaining independent of） the transverse van Hove singularity without and with local coordination number fluctuation. In the presence of a single type of disorder, ωTR 〉 wBp, and ωTIR≈BP only when the disorder is sufficiently strong and causes spatial fluctuation of the local coordination number. Moreover, if there is no positional disorder, ωTIR ≈ωLIR. Therefore, the argument that the boson peak is equivalent to the transverse Ioffe-Regel limit is not general. Our results suggest that both local coordination number and positional disorder are necessary for the argument to hold, which is actually the case for most disordered solids such as marginally jammed solids and structural glasses. We further combine two types of disorders to cause disorder in both the local coordination number and lattice site position. The density of vibrational states of the resulting networks resembles that of marginally jammed solids well. However, the relation between the boson peak and the transverse Ioffe-Regel limit is still indefinite and condition-dependent. Therefore, the interplay between different types of disorders is complicated, and more in-depth studies are required to sort it out.

关键词： disorder boson peak Ioffe-Regel limit amorphous solid

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可食用昆虫蛋白的医药领域研究进展

食品工业 2024年第5期45卷 288-291页

作者：苟梦星魏煜铠仝画郑州工程技术学院化工食品学院郑州450053

随着全球对新型可食用资源的关注度增加,昆虫蛋白质成为了新的研究热点。本文综述了近年来昆虫蛋白在医药领域的研究进展,包括免疫、抗菌、抗病毒、抗肿瘤、抗氧化、抗炎、降血压、降血糖等方面。结果显示,昆虫蛋白含有丰富的生物活性物... 详细信息

随着全球对新型可食用资源的关注度增加,昆虫蛋白质成为了新的研究热点。本文综述了近年来昆虫蛋白在医药领域的研究进展,包括免疫、抗菌、抗病毒、抗肿瘤、抗氧化、抗炎、降血压、降血糖等方面。结果显示,昆虫蛋白含有丰富的生物活性物质,使其在医药领域有着广阔的应用前景。文章可为昆虫蛋白的研究和进一步开发利用提供一定参考,为昆虫蛋白促进人类健康事业发展做出指导。

关键词：昆虫蛋白抗菌肽医学领域应用

Electronic Localization Length of Carbon Nanotubes with Different Chiral Symmetries

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Chinese Physics Letters 2001年第8期18卷 1105-1107页

作者： YANG hua-tong DONG Jin-Ming XING Ding-Yu Department of Physics and National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093

The electronic localization lengthsλof metallic carbon nanotubes with different chiral symmetries have been calculated by one parameter scaling *** is found thatλis independent of the nanotube chirality,but depends linearly on their *** dependence ofλon the disorder strength W has also been studied,and a power-law relation betweenλand W is also found to be independent of the tube *** numerical results are in good agreement with recent experimental observations and other theoretical result for only the“armchair”nanotubes.

关键词： diameters scaling Carbon

A novel trilinear decomposition algorithm:Three-dimension non-negative matrix factorization

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Chinese Chemical Letters 2007年第4期18卷 495-498页

作者： Hong Tao Gao Dong Mei Dai tong hua Li College of Chemistry and Molecular Engineering Qingdao University of Science ＆ Technology Qingdao 266042 China Department of Chemistry Jining Teachers College Jining 273100 China Department of Chemistry Tongji University Shanghai 200092 China

Non-negative matrix factorization （NMF） is a technique for dimensionality reduction by placing non-negativity constraints on the matrix. Based on the PARAFAC model, NMF was extended for three-dimension data decomposition. The three-dimension nonnegative matrix factorization （NMF3） algorithm, which was concise and easy to implement, was given in this paper. The NMF3 algorithm implementation was based on elements but not on vectors. It could decompose a data array directly without unfolding, which was not similar to that the traditional algorithms do, It has been applied to the simulated data array decomposition and obtained reasonable results. It showed that NMF3 could be introduced for curve resolution in chemometrics.

关键词： Three-dimension non-negative matrix factorization NMF3 Algorithm Data decomposition Chemometrics

M2C-GVIO:motion manifold constraint aided GNSS-visual-inertial odometry for ground vehicles

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Satellite Navigation 2023年第1期4卷 77-91,I0003页

作者： tong hua Ling Pei Tao Li Jie Yin Guoqing Liu Wenxian Yu Shanghai Key Laboratory of Navigation and Location Based Services Shanghai Jiao Tong UniversityShanghaiChina

Visual-Inertial Odometry(VIO)has been developed from Simultaneous Localization and Mapping(SLAM)as a lowcost and versatile sensor fusion approach and attracted increasing attention in ground vehicle ***,VIOs usually have the degraded performance in challenging environments and degenerated motion *** this paper,we propose a ground vehicle-based VIO algorithm based on the Multi-State Constraint Kalman Filter(MSCKF)*** on a unifed motion manifold assumption,we derive the measurement model of manifold constraints,including velocity,rotation,and translation *** we present a robust flter-based algorithm dedicated to ground vehicles,whose key is the real-time manifold noise estimation and adaptive measurement ***,GNSS position measurements are loosely coupled into our approach,where the transformation between GNSS and VIO frame is optimized ***,we theoretically analyze the system observability matrix and observability *** algorithm is tested on both the simulation test and public datasets including Brno Urban dataset and Kaist Urban *** compare the performance of our algorithm with classical VIO algorithms(MSCKF,VINS-Mono,R-VIO,ORB_SLAM3)and GVIO algorithms(GNSS-MSCKF,VINS-Fusion).The results demonstrate that our algorithm is more robust than other compared algorithms,showing a competitive position accuracy and computational efciency.

关键词： Sensor fusion Visual-inertial odometry Motion manifold constraint

Elastoplastic analysis for infinite plate with centric crack loaded by two pairs of point shear forces

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Journal of Central South University of Technology 2005年第Z1期12卷 189-193页

作者： ZHOU Xiao-ping LING tong-hua School of Civil Engineering Chongqing University Chongqing 400045 China School of Geoscience and Environmental Engineering Central South University Changsha 410083 China

The near crack line analysis method was used to investigate a crack loaded by two pairs of point shear forces in an infinite plate in an elastic-perfectly plastic solid, and the analytical solution was obtained. The solutions include: the unit normal vector of the elastic-plastic boundary near the crack line, the elastic-plastic stress fields near crack line, law that the length of the plastic zone along the crack line is varied with an external loads, and the bearing capacity of an infinite plate with a center crack loaded by two pairs of point shear forces. The results are sufficiently precise near the crack line because the assumptions of the small scale yielding theory have not been made and no other assumption have been taken.

关键词： near crack line analysis method elastoplastie analytical solution two pairs of point shear forces

Algal biomass derived biochar anode for efficient extracellular electron uptake from Shewanella oneidensis MR-1

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Frontiers of Environmental Science & Engineering 2018年第4期12卷 109-117页

作者： Yan-ShanWang Dao-Bo Li Feng Zhang Zhong-hua tong Han-Qing Yu CAS Key Laboratory of Urban Pollutant Conversion Department of Applied Chemistry University of Science & Technology of China Hefei 230026 China Anhui Province Key Laboratory of Polar Environment and Global Change University of Science & Technology of China. Hefei 230026 China"

The development of cost-effective and highly efficient anode materials Ibr extracellular electron uptake is important to improve the electricity generation ofbioelectrochemical systems. An effective approach to mitigate harmful algal bloom （HAB） is mechanical harvesting of algal biomass, thus subsequent processing for the collected algal biomass is desired. In this study, a low-cost biochar derived from algal biomass via pyrolysis was utilized as an anode material tbr efficient electron uptake. Electrochemical properties of the algal biochar and graphite plate electrodes were characterized in a bioelectrochemical system （BES）. Compared with graphite plate electrode, the algal biochar electrode could effectively utilize both indirect and direct electron transfer pathways tbr current production, and showed stronger electrochemical response and better adsorption of redox mediators. The maximum current density of algal biochar anode was about 4.1 times higher than graphite plate anode in BES. This work provides an application potential for collected HAB to develop a cost-effective anode material for eff-cient extracellular electron uptake in BES and to achieve waste resource utilization.

关键词： Algal biochar Anode material Electrochemical activity Extracellular electron transport Waste resource utilization

Relativistic motion on Gaussian quantum steering for two-mode localized Gaussian states

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Chinese Physics B 2022年第5期31卷 189-196页

作者： Xiao-Long Gong Shuo Cao Yue Fang tong-hua Liu School of Physics and Optoelectronic Yangtze UniversityJingzhou 434023China Department of Astronomy Beijing Normal UniversityBeijing 100875China Advanced Institute of Natural Sciences Beijing Normal University at ZhuhaiZhuhai 519087China

Realistic quantum systems always exhibit gravitational and relativistic *** this paper,we investigate the properties of Gaussian steering and its asymmetry by the localized two-mode Gaussian quantum states,instead of the traditional single-mode approximation method in the relativistic *** find that the one-side Gaussian quantum steering will monotonically decrease with increasing observers of ***,our results also reveal the interesting behavior of the Gaussian steering asymmetry,which increases for a specific range of accelerated parameter and then gradually approaches to a finite *** finding is well consistent and explained by the well-known Unruh effect,which could significantly destroy the one-side Gaussian quantum ***,our results could also be applied to the dynamical studies of Gaussian steering between the Earth and satellites,since the effects of acceleration are equal to the effects of gravity according to the equivalence principle.

关键词： relativistic quantum information quantum nonlocality Unruh effect