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Design and motion analysis of reconfigurable wheel-legged mobile robot

Defence Technology（防务技术） 2022年第6期18卷 1023-1040页

作者： Shuo Zhang jian-tao Yao Ying-bin Wang Zi-sheng Liu Yun-dou Xu Yong-sheng Zhao School of Mechanical Engineering Yanshan UniversityHebeiChina

An adaptive wheel-legged shape reconfigurable mobile robot,based on a scissor-like mechanism,is proposed for an obstacle detecting and surmounting robot,moving on complex terrain.The robot can dynamically adjust its own shape,according to the environment,realizing a transformation of wheel shape into leg shape and vice versa.Each wheel-legged mechanism has one degree of freedom,which means that only the relative motion of the inner and outer discs is needed to achieve the transformation of the shape into a wheel or a leg.First,the force analysis of the conversion process of the wheel-legged mechanism is carried out,while the relationship between the driving torque and the friction factor in the non-conversion trigger stage and in the conversion trigger stage is obtained.The results showed that the shape conversion can be better realized by increasing the friction factor of the trigger point.Next,the kinematics analysis of the robot,including climbing the obstacles,stairs and gully,is carried out.The motion of the spokes tip is obtained,in order to derive the folding ratio and the surmountable obstacle height of the wheel-legged mechanism.The parameters of the wheel-legged structure are optimized,to obtain better stability and obstacle climbing ability.Finally,a dynamic simulation model is established by ADAMS,to verify the obstacle climbing performance and gait rationality of the robot,in addition to a prototype experiment.The results showed that the surmountable obstacle height of the robot is about3.05 times the spoke radius.The robot has the stability of a traditional wheel mechanism and the obstacle surmount performance of a leg mechanism,making it more suitable for field reconnaissance and exploration missions.

关键词： Mobile robots Scissor mechanism Kinematics ADAMS simulation Obstacle surmounting

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Advances in extraction and analysis of phenolic compounds from plant materials

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Chinese Journal of Natural Medicines 2017年第10期15卷 721-731页

作者： XU Cong-Cong WANG Bing PU Yi-Qiong TAO Jian-Sheng ZHANG Tong Experiment Ceiter of Teaching and Learning Shanghai University of Traditional Chinese Medicine Shanghai 201203 China School of Phar nacy Shanghai University of Traditional Chinese Medicine Shanghai 201203 China

Phenolic compounds,the most abundant secondary metabolites in plants,have received more and more attention in recent years because of their distinct bioactivities.This review summarizes different types of phenolic compounds and their extraction and analytical methods used in the recent reports,involving 59 phenolic compounds from 52 kinds of plants.The extraction methods include solid–liquid extraction,ultrasound-assisted extractions,microwave-assisted extractions,supercritical fluid extraction,and other methods.The analysis methods include spectrophotometry,gas chromatography,liquid chromatography,thin-layer chromatography,capillary electrophoresis,and near-infrared spectroscopy.After illustrating the specific conditions of the analytical methods,the advantages and disadvantages of each method are also summarized,pointing out their respective suitability.This review provides valuable reference for identification and/or quantification of phenolic compounds from natural products.

关键词： Phenolic compounds Flavonoid Extraction Quantification Liquid chromatography Gas chromatography

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Transport in electron–photon systems

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Frontiers of physics 2023年第4期18卷 129-175页

作者： jian-sheng Wang Jiebin Peng Zu-Quan Zhang Yong-Mei Zhang tao Zhu Department of Physics National University of SingaporeSingapore 117551Republic of Singapore Center for Phononics and Thermal Energy Science China-EU Joint Center for NanophononicsShanghai Key Laboratory of Special Artificial Microstructure Materials and TechnologySchool of Physics Science and EngineeringTongji UniversityShanghai 200092China Department of Physics Zhejiang Normal UniversityJinhua 321004China College of Physics Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Electronic and Information Engineering Tiangong UniversityTianjin 300387China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

We review the description and modeling of transport phenomena among the electron systems coupled via scalar or vector photons.It consists of three parts.The first part is about scalar photons,i.e.,Coulomb interactions.The second part is with transverse photons described by vector potentials.The third part is onϕ=0 or temporal gauge,which is a full theory of the electrodynamics.We use the nonequilibrium Green’s function(NEGF)formalism as a basic tool to study steady-state transport.Although with local equilibrium it is equivalent to the fluctuational electrodynamics(FE),the advantage of NEGF is that it can go beyond FE due to its generality.We have given a few examples in the review,such as transfer of heat between graphene sheets driven by potential bias,emission of light by a double quantum dot,and emission of energy,momentum,and angular momentum from a graphene nanoribbon.All of these calculations are based on a generalization of the Meir–Wingreen formula commonly used in electronic transport in mesoscopic systems,with materials properties represented by photon self-energy,coupled with the Keldysh equation and the solution to the Dyson equation.

关键词： quantum transport thermal radiation scalar and vector photons nonequilibrium Green's function

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Analysis and Optimization of a Spatial Parallel Mechanism for a New 5-DOF Hybrid Serial-Parallel Manipulator

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Chinese Journal of Mechanical Engineering 2018年第3期31卷 60-68页

作者： Dong-sheng Zhang Yun-Dou Xu jian-tao Yao Yong-sheng Zhao Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan University Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of National Education Yanshan University

Hybrid manipulators have potentially application in machining industries and attract extensive attention from many researchers on the basis of high sti ness and high dexterity. Therefore,in order to expand the application prospects of hybrid manipulator,a novel 5?degree?of?freedom(DOF) hybrid serial?parallel manipulator(HSPM) is proposed. Firstly,the design plan of this manipulator is introduced. Secondly,the analysis of this manipulator is carried out in detail,including kinematics analysis,statics analysis,and workspace analysis. Especially,an amplitude equivalent method of disposing the over?constrained force/couple to the non?overconstrained force/couple is used in the statics analysis. Then,three performance indices are used to optimize the PM. Two of them have been widely used,and the third one is a new index which considers the characteristics of the actuated force. Based on the performance indices,the performance atlas is drawn and the optimal design of the PM is investigated. In order to satisfy the anticipant kinetic characteristics of the PM,the verification of the optimized physical dimension is done and the workspace based on the optimized physical dimension is carried out. This paper will lay good theoretical foundations for application of this novel HSPM and also can be applied to other hybrid manipulators.

关键词： Parallel mechanism Performance indices Optimal design Performance atlas

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Trace Analysis of Anions in Perfluorodecalin by Green Liquid-Liquid Extraction Combined with Ion Chromatography

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Journal of Analysis and Testing 2022年第3期6卷 346-351页

作者： sheng Liu jian Xu Yu Lu Yong Huang Zhi-Wen Fang Mei Lv Li-tao Wang The Technical Center of Zibo Customs Zibo 255031China Suzhou Jieshitong Medical Equipment Co. Ltd.Suzhou 215000China School of Pharmacy Jining Medical UniversityJining 272000China Jining Medical University No.669Xueyuan RoadRizhao 276800China

Perfluoronaphthenes,with inert chemical and biological properties and ability to dissolve large amounts of oxygen,have received the most attention in medical applications.However,the excessive anion contained may cause some side effects.Herein,liquid-liquid extraction technique with shaking and ultrasonic extraction was used for the trace analysis of five anions(F^(-),Cl^(-),NO_(3)^(-),PO_(4)^(3-),SO_(4)^(2-))in perfluorodecalin using water as green extractant.The optimum pretreatment technology and ion chromatography detection conditions were established.Good linearity was observed in each concentration range,and the linear correlation coefficient(R^(2))was better than 0.997.The limits of detection(S/N=3)of five anions from perfluorodecalin were 3.2,5.5,14.2,23.2 and 29.5μg/L,respectively.The established method with high sensitivity and accuracy has been successfully appliedfor the determination of five anions in three perfluorodecalin products,which provides a basis for further development of green detection and quality standard formulation in perfluorodecalin and other fluorocarbon solvents.

关键词： Perfluorodecalin Trace analysis Anions Liquid-liquid extraction Ion chromatography

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Cellular model of neuronal atrophy induced by DYNC111 deficiency reveals protective roles of RAS-RAF-MEK signaling

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Protein & Cell 2016年第9期7卷 638-650页

作者： Zhi-Dong Liu Su Zhang jian-Jin Hao tao-Rong Xie jian-sheng Kang Key Laboratory of Nutrition and Metabolism Institute for Nutritional Sciences Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200231 China University of Chinese Academy of Sciences Beijing 100049 China

Neuronal atrophy is a common pathological feature occurred in aging and neurodegenerative diseases. A variety of abnormalities including motor protein mal- function and mitochondrial dysfunction contribute to the loss of neuronal architecture; however, less is known about the intracallular signaling pathways that can pro- tect against or delay this pathogenic process. Here, we show that the DYNClll deficiency, a neuron-specific dynein intermediate chain, causes neuronal atrophy in primary hippocampal neurons. With this cellular model, we are able to find that activation of RAS-RAF.MEK signaling protects against neuronal atrophy induced by DYNClll deficiency, which relies on MEK-dependent autophagy in neuron. Moreover, we further reveal that BRAF also protects against neuronal atrophy induced by mitochondrial impairment. These findings demon- strate protective roles of the RAS-RAF-MEK axis against neuronal atrophy, and imply a new therapeutic target for clinical intervention.

关键词： RAS-RAF-MEK pathway atrophy dyneinintermediate chain mitochondria hippocampal neuron,autophagy

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Effect of Mn Modification on the Corrosion Susceptibility of Mg–Mn Alloys by Magnesium Scrap

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Acta Metallurgica Sinica(English Letters) 2021年第1期34卷 1-11页

作者： Dong-Dong Gu jian Peng Jia-Wen Wang Zheng-tao Liu Fu-sheng Pan State Key Laboratory of Mechanical Transmission College of Materials Science and EngineeringChongqing UniversityChongqing 400044China Chongqing Research Center for Advanced Materials Chongqing Academy of Science and TechnologyChongqing 401123China

The microstructure and anti-corrosion behavior of Mg–Mn alloys by magnesium scrap have been investigated in this study.The results show that the size of the Fe-rich particles in magnesium scrap decreases but the quantity increases with the Mn addition.Although the presence of Mn-containing Fe-rich particles with unique symbiotic structure can eff ectively weaken the micro-galvanic corrosion,the presence of more free Fe(Fe-rich particles)does not necessarily lead to severe corrosion of the alloy.The corrosion susceptibility of Mg–Mn–Fe alloy primarily depends on the solubility of iron in the Mg matrix,while it can be significantly reduced by suitable Mn addition.Besides,the tolerance limit of the Fe impurity can be expressed as Femax=0.0083 Mn(relative to the iron solubility).Only when the Fe/Mn ratio is below 0.0083 can the alloy have excellent corrosion resistance,with the corrosion rate changing in the scope of 0.38±0.09 to 0.54±0.15 mg/cm^(2) day and icorr from 3 to 9×10^(–4) A/cm^(2).

关键词： Magnesium scrap Mn modification Fe impurity Corrosion susceptibility Corrosion resistance

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Methods for Force Analysis of Overconstrained Parallel Mechanisms： A Review

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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1460-1472页

作者： Wen-Lan Liu Yun-Dou Xu jian-tao Yao Yong-sheng Zhao Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan University Qinhuangdao 066004 China Key Laboratory of Advanced Forging and StampingTechnology and Science of Ministry of National Education Yanshan University Qinhuangdao 066004 China

The force analysis of overconstrained PMs is relatively complex and difficult, for which the methods have always been a research hotspot. However, few liter- atures analyze the characteristics and application scopes of the various methods, which is not convenient for researchers and engineers to master and adopt them prop- erly. A review of the methods for force analysis of both passive and active overconstrained PMs is presented. The existing force analysis methods for these two kinds of overconstrained PMs are classified according to their main ideas. Each category is briefly demonstrated and evaluated from such aspects as the calculation amount, the compre- hensiveness of considering limbs＇ deformation, and the existence of explicit expressions of the solutions, which provides an important reference for researchers and engi- neers to quickly find a suitable method. The similarities and differences between the statically indeterminate prob- lem of passive overconstrained PMs and that of active overconstrained PMs are discussed, and a universal method for these two kinds of overconstrained PMs is pointed out. The existing deficiencies and development directions of the force analysis methods for overconstrained systems are indicated based on the overview.

关键词： Redundantly actuated PM ~ Passiveoverconstrained PM ~ Statically indeterminate problemForce analysis ~ Weighted generalized inverse

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Dye-based mito-thermometry and its application in thermogenesis of brown adipocytes

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Biophysics Reports 2017年第Z2期3卷 85-91页

作者： tao-Rong Xie Chun-Feng Liu jian-sheng Kang CAS Key Laboratory of Nutrition and Metabolism Institute for Nutritional SciencesShanghai Institutes for Biological SciencesGraduate School of the Chinese Academy of SciencesChinese Academy of Sciences

Mitochondrion is the main intracellular site for thermogenesis and attractive energy expenditure targeting for obesity therapy. Here, we develop a method of mitochondrial thermometry based on Rhodamine B methyl ester, which equilibrates as a thermosensitive mixture of nonfluorescent and fluorescent resonance forms. Using this approach, we are able to demonstrate that the efficacy of norepinephrine-induced thermogenesis is low, and measure the maximum transient rate of temperature increase in brown adipocytes.

关键词： Brown adipocytes Mitochondrial thermometry Nanothermometry Thermogenesis

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Globulin-platelet model predicts minimal fibrosis and cirrhosis in chronic hepatitis B virus infected patients

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World Journal of Gastroenterology 2012年第22期18卷 2784-2792页

作者： Xu-Dong Liu jian-Lin Wu jian Liang tao Zhang Qing-Shou sheng Department of Liver Diseases Ruikang Hospital of Guangxi Tra-ditional Chinese Medicine University Nanning 530011 GuangxiZhuang Autonomous Region China Department of Infectious Disease the First Affili- ated Hospital of Guangxi Medical University Nanning 530021 Guangxi Zhuang Autonomous Region China

AIM: To establish a simple model consisting of the routine laboratory variables to predict both minimal fibrosis and cirrhosis in chronic hepatitis B virus (HBV)-infected patients. METHODS: We retrospectively investigated 114 chronic HBV-infected patients who underwent liver biopsy in two different hospitals. Thirteen parameters were analyzed by step-wise regression analysis and correlation analysis. A new fibrosis index [globulin/platelet (GP) model] was developed, including globulin (GLOB) and platelet count (PLT). GP model = GLOB (g/mL) × 100/PLT (× 109/L). We evaluated the receiver operating characteristics analysis used to predict minimal fibrosis and compared six other available models. RESULTS: Thirteen clinical biochemical and hematological variables [sex, age, PLT, alanine aminotransferase, aspartate aminotransferase (AST), albumin, GLOB, total bilirubin (T.bil), direct bilirubin (D.bil), glutamyltransferase, alkaline phosphatase, HBV DNA and prothrombin time (PT)] were analyzed according to three stages of liver fibrosis (F0-F1, F2-F3 and F4). Bivariate Spearman's rank correlation analysis showed that six variables, including age, PLT, T.bil, D.bil, GLOB and PT, were correlated with the three fibrosis stages (FS). Correlation coefficients were 0.23, -0.412, 0.208, 0.220, 0.314 and 0.212; and P value was 0.014, < 0.001, 0.026, 0.018, 0.001 and 0.024, respectively. Univariate analysis revealed that only PLT and GLOB were significantly different in the three FS (PLT: F = 11.772, P < 0.001; GLOB: F = 6.612, P = 0.002). Step-wise multiple regression analysis showed that PLT and GLOB were also independently correlated with FS (R 2 = 0.237). By Spearman's rank correlation analysis, GP model was significantly correlated with the three FS (r = 0.466, P < 0.001). The median values in F0-F1, F2-F3 and F4 were 1.461, 1.720 and 2.634. Compared with the six available models (fibrosis index, AST-platelet ratio, FIB-4, fibrosis-cirrhosis index and age-AST model and age-PLT ratio), GP model showed a highest correlation

关键词：血小板计数模型预测肝纤维化病毒感染肝硬化球蛋白患者乙肝

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