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Influence of Liquid Isoprene Rubber on Strain Softening of Carbon Black Filled Isoprene Rubber Nanocomposites

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Chinese Journal of Polymer Science 2021年第7期39卷 887-895页

作者： Feng-Yi hou Yi-hu Song Qiang Zheng MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

The reinforcement of rubbers by nanoparticles is always accompanied with enhanced dissipation of mechanical energy upon large *** for solving the contradiction between improving reinforcement and reducing energy dissipation for rubber nanocomposites have not been well *** carbon black(CB)filled isoprene rubber(IR)/liquid isoprene rubber(LR)blend nanocomposites with similar crosslink density(ve)are prepared and influence of LR on the strain softening behaviors including Payne effect under large amplitude shear deformation and Mullins effect under cyclic uniaxial deformation is *** introduction of LR could improve the frequency sensitivity of loss modulus and reduce critical strain amplitude for Payne effect and loss modulus at the low ***,tuning ve and LR content allows reducing mechanical hysteresis in Mullins effect without significant impact on the mechanical *** investigation is illuminating for manufacturing nanocomposite vulcanizates with balanced mechanical hysteresis and reinforcement effect.

关键词： Rubber nanocomposites Stress softening Mechanical hysteresis Liquid rubber

血能铁制剂对哺乳母猪生产性能及生理生化指标的影响

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农业生物技术学报 2025年第1期33卷 116-123页

作者：胡国明黄昌巧周淑棉韦玉衡谢小东胡庭俊胡永浩甘肃农业大学动物医学院广西大学动物科学技术学院贵港市动物疫病预防控制中心

铁作为一种关键的微量元素，对动物的生长具有重大的意义，铁缺乏将会导致发育障碍、繁殖性能不佳、贫血和腹泻等多种不良影响。本研究以产前7 d至产后21 d的哺乳母猪(Sus scrofa domestica)为对象，探讨饲料中添加血能铁制剂对哺乳母... 详细信息

铁作为一种关键的微量元素，对动物的生长具有重大的意义，铁缺乏将会导致发育障碍、繁殖性能不佳、贫血和腹泻等多种不良影响。本研究以产前7 d至产后21 d的哺乳母猪(Sus scrofa domestica)为对象，探讨饲料中添加血能铁制剂对哺乳母猪生产性能、生理生化指标及仔猪相关指标的影响。结果显示，与空白对照组相比，以1 kg/t饲料添加剂量添加血能铁制剂后，连续饲喂28 d能够显著降低母猪助产率、提高断配率，改善母猪产程，增加仔猪初生窝重、仔猪平均体重、断奶窝重，降低仔猪腹泻率、畸形率、死胎率，从而提高母猪生产性能和仔猪生长性能；同时血能铁制剂可以提高第7天哺乳仔猪血清铁和总铁结合力，起到预防仔猪贫血的作用。本研究为兽医临床应用血能铁制剂提高母猪生产性能提供参考和依据。

关键词：血能铁制剂生产性能血液指标

Symplectic system based analytical solution for bending of rectangular orthotropic plates on Winkler elastic foundation

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Acta Mechanica Sinica 2011年第6期27卷 929-937页

作者： Wei-An Yao xiao-Fei hu Feng xiao State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology 116024 Dalian China Department of Computer Science Dalian Medical University 116044 Dalian China

This paper analyses the bending of rectangular orthotropic plates on a Winkler elastic *** definition of symplectic inner product and symplectic space formed by generalized displacements establish dual variables and dual equations in the symplectic *** operator matrix of the equation set is proven to be a Hamilton operator *** of variables and eigenfunction expansion creates a basis for analyzing the bending of rectangular orthotropic plates on Winkler elastic foundation and obtaining solutions for plates having any boundary *** is discussion of symplectic eigenvalue problems of orthotropic plates under two typical boundary conditions,with opposite sides simply supported and opposite sides *** equations of eigenvalues and symplectic eigenvectors in analytical form *** solutions using two examples are presented to show the use of the new methods described in this *** verify the accuracy and convergence,a fully simply supported plate that is fully and simply supported under uniformly distributed load is used to compare the classical Navier method,the Levy method and the new *** show that the new technique has good accuracy and better convergence speed than other methods,especially in relation to internal forces.A fully clamped rectangular plate on Winkler foundation is solved to validate application of the new methods,with solutions compared to those produced by the Galerkin method.

关键词： Orthotropic plate Symplectic space Winklerelastic foundation Analytical solution

Numerical Study on Characteristics of Supercavitating Flow Around the Variable-Lateral-Force Cavitator

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China Ocean Engineering 2017年第1期31卷 123-129页

作者： hu xiao GAO Ye SHI xiao-tao College of Hydraulic and Environmental Engineering China Three Gorges University Yichang 443008 China Engineering Research Center of Eco-environment in Three Gorges Reservoir Region Ministry of Education China Three Gorges University Yichang 443008 China Department of Aerospace and Building Engineering Harbin Engineering University Harbin 150001 China

A control scheme named the variable-lateral-force cavitator, which is focused on the control of lift force, drag force and lateral forces for underwater supercavity vehicles was proposed, and the supercavitating flow around the cavitator was investigated numerically using the mixture multiphase flow model. It is verified that the forces of pitching, yawing, drag and lift, as well as the supercavity size of the underwater vehicle can be effectively regulated through the movements of the control element of the variable-lateral-force cavitator in the radial and circumferential directions. In addition, if the control element on either side protrudes to a height of 5% of the diameter of the front cavitator, an amount of forces of pitching and yawing equivalent to 30% of the drag force will be produced, and the supercavity section appears concave inwards simultaneously. It is also found that both the drag force and lift force of the variable-lateral-force cavitator decline as the angle of attack increases.

关键词： supercavitating flow cavitator drag force lateral forces numerical investigation

Removal of baseline wander from ECG signal based on a statistical weighted moving average filter

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第5期12卷 397-403页

作者： xiao hu Zhong xiao NiZHANG School of Mechanical and Electric Engineering Guangzhou University Guangzhou 510006 China Guangdong General Hospital Guangzhou 510080 China

Baseline wander is a common noise in electrocardiogram (ECG) *** effectively correct the baseline and to preserve more underlying components of an ECG signal,we propose a simple and novel filtering method based on a statistical weighted moving average *** a and b are theminimum and maximum of all sample values within a moving window,***,the whole region [a,b] is divided into M equal sub-regions without ***,three sub-regions with the largest sample distribution probabilities are chosen (except M<3) and incorporated into one region,denoted as [a 0,b 0 ] for ***,for every sample point in the moving window,its weight is set to 1 if its value falls in [a 0,b 0 ];otherwise,its weight is ***,all sample points with weight 1 are averaged to estimate the *** algorithm was tested by simulated ECG signal and real ECG signal from *** results showed that the proposed filter could more effectively extract baseline wander from ECG signal and affect the morphological feature of ECG signal considerably less than both the traditional moving average filter and wavelet package translation did.

关键词： ECG signal Baseline wander Morphological feature Moving average filter Wavelet package translation

Coupling Vibration of Simply-Supported Damping Beam Carrying a Moving Mass

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Acta Mechanica Solida Sinica 2022年第6期35卷 972-978页

作者： Jingjing hu Weipeng hu Chuan xiao Zichen Deng School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an710072China School of Civil Engineering and Architecture Xi’an University of TechnologyXi’an710048China State Key Laboratory of Eco-Hydraulics in Northwest Arid Region of China Xi’an University of TechnologyXi’an710048China China Research and Development Academy of Machinery Equipment Beijing100089China

The coupling dynamic problems,such as the vehicle-bridge interaction problem,are difficult to be *** this paper,the generalized multi-symplectic approach is employed to investigate the coupling dynamic behaviors in the vehicle-bridge interaction system.A simply-supported damping beam model carrying a moving mass is considered and the generalized multi-symplectic form with the dynamical symmetry breaking factors is deduced *** then,Preissmann’s scheme is employed to discretize the generalized multi-symplectic form,and the discrete structure-preserving condition for the numerical scheme is *** to the discrete structure-preserving condition,the permitted moving speed of the mass with different damping factors and different time step lengths is obtained to ensure the structure-preserving properties of the numerical ***,the effects of the damping factor of the beam and the moving speed of the mass on the vibration of the beam are investigated by Preissmann’s *** main contribution of this work is to provide a structure-preserving analysis approach for the vehicle-bridge interaction problem.

关键词： Vehicle-bridge interaction Dynamical symmetry breaking Generalized multi-symplectic Hamiltonian Moving mass

Prediction of Hyperuricemia Risk Based on Medical Examination Report Analysis

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Journal of Systems Science and Systems Engineering 2020年第4期29卷 468-503页

作者： Rong hou Yongbo xiao Yan Zhu Hongyan Zhao Research Center for Contemporary Management School of Economics and ManagementTsinghua UniversityBeijing 100084China Institute of Industry Internet Tsinghua UniversityBeijing 100084China

This study hopes to contribute to disease detection by analyzing a medical examination dataset with 123,968 *** on association rules mining and related medical knowledge,6 models were constructed here to predict hyperuricemia prevalence and investigated its risk *** different models,the prediction performances of Lasso logistic regression,traditional logistic regression,and random forest are excellent,and the results can be *** logistic regression model also works well,but it is not ***'s prediction performance is relatively poor,while data dimensionality reduction can significantly improve its *** has the worst performance and its efficiency of processing high-dimensional large dataset is extremely *** risk factors of hyperuricemia mainly belongs to 4 categories,which are obesity-related factors,renal function factors,liver function factors,and myeloproliferative diseases-related *** forest,Lasso regression,and logistic regression all treat serum creatinine,BMI,triglyceride,fatty liver,and age as key predictive *** also show that serum urea,serum alanine aminotransferase,negative urobilinogen,red blood cell count,white blood cell count and the pH are significantly correlated with the risk.

关键词： Medical examination hyperuricemia machine learning risk prediction risk factors

Investigation of high rate mechanical flow followed by ignition for high-energy propellant under dynamic extrusion loading

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Defence Technology（防务技术） 2024年第2期32卷 336-347页

作者： Liying Dong Yanqing Wu Kun Yang xiao hou State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

Investigating the ignition response of nitrate ester plasticized polyether(NEPE) propellant under dynamic extrusion loading is of great significant at least for two cases. Firstly, it helps to understand the mechanism and conditions of unwanted ignition inside charged propellant under accident ***, evaluates the risk of a shell crevice in a solid rocket motor(SRM) under a falling or overturning scene. In the present study, an innovative visual crevice extrusion experiment is designed using a dropweight apparatus. The dynamic responses of NEPE propellant during extrusion loading, including compaction and compression, rapid shear flow into the crevice, stress concentration, and ignition reaction, have been firstly observed using a high-performance high-speed camera. The ignition reaction is observed in the triangular region of the NEPE propellant sample above the crevice when the drop weight velocity was 1.90 m/s. Based on the user material subroutine interface UMAT provided by finite element software LS-DYNA, a viscoelastic-plastic model and dual ignition criterion related to plastic shear dissipation are developed and applied to the local ignition response analysis under crevice extrusion conditions. The stress concentration occurs in the crevice location of the propellant sample, the shear stress is relatively large, the effective plastic work is relatively large, and the ignition reaction is easy to occur. When the sample thickness decreases from 5 mm to 2.5 mm, the shear stress increases from 22.3 MPa to 28.6 MPa, the critical value of effective plastic work required for ignition is shortened from 1280 μs to 730 μs, and the triangular area is easily triggering an ignition reaction. The propellant sample with a small thickness is more likely to stress concentration, resulting in large shear stress and effective work, triggering an ignition reaction.

关键词： NEPE propellant Crevice extrusion Shear flow Sample thickness Ignition reaction

Application of modified quartz crystal sensors:Detection of isobutyl alcohol,ethyl acetate and ethylene

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International Journal of Agricultural and Biological Engineering 2014年第5期7卷 71-77页

作者： hou Juncai hu Yaohua Guo Kangquan College of Mechanical and Electronic Engineering Northwest A&F UniversityYangling 712100China

Aroma volatilization is one of the very important attributes of agricultural products during *** of aroma compounds experience changes over products’different ripening *** paper aimed to develop a detection system based on modified quartz crystal sensors to detect volatile organic compounds(VOCs).By drop-coating on sensors’surface,four sensors were made using quartz crystal resonators coated with four different absorbable materials:ethyl cellulose,cellulose acetate,1,2-dioleoyl-sn-glycero-3-[phosphor-L-serine],and galactosyl *** the diversely coated sensors,three VOCs:isobutyl alcohol,ethyl acetate and ethylene were detected at ppm *** investigate the structure influence of the coated sensing films on VOCs absorption,the topography of films was imaged in 3D using atomic force microscopy(AFM)in tap mode for qualitative analysis of gas *** selectivity and sensitivity were investigated when sensors were exposed to VOCs with increasing *** results showed that the frequency shift of sensors was linear to the concentrations of all three VOCs in the range of 5-25 *** values reaching over 4.5 Hz/ppm,the sensitivity of cellulose acetate coated sensor to three VOCs was similar,higher than that of sensors with other *** high sensitivity of the cellulose acetate coated sensor might be due to the film’s rough surface and porous *** results may help further research on detection of fruits’organic volatiles during the ripening stage.

关键词： quartz crystal sensor atomic force microscopy detection selectivity sensitivity volatile organic compounds