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Viscoelastic Evaluation of Different Hyaluronic Acid Based Fillers Using Vibrational Optical Coherence Tomography 预览
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作者 Frederick H. Silver Ruchit G. Shah +3 位作者 Nikita Kelkar Dominick Benedetto Dale DeVore Justin Cohen 《材料科学与应用期刊(英文)》 2019年第5期423-431,共9页
Hylauronic acid (HA) is used as a viscoelastic in Ophthalmology during cataract surgery based on its high viscosity at rest, its ability to shear thin and dissipate energy during phacoemulsification. However, these pr... Hylauronic acid (HA) is used as a viscoelastic in Ophthalmology during cataract surgery based on its high viscosity at rest, its ability to shear thin and dissipate energy during phacoemulsification. However, these properties of HA solutions would make them susceptible to migration when used as dermal filler materials. In this study, we apply a new technique termed vibrational optical coherence tomography (VOCT) to compare the physical properties of different HA solutions and fillers used in facial aesthetics. Results presented in this study suggest that HA solutions and HA dermal fillers have markedly different physical properties. HA solutions are highly viscoelastic with high % viscous losses while fillers tend to have lower viscous energy dissipation properties. Clinical observations suggest that the high loss fillers are injected more superficially in the face where tension and internal and external forces are more likely minimized giving tissue of the hands and lips more volume and allowing more natural movement. In contrast, the lower loss gels that are used to lift tissue, generally have a higher G’, and are injected deeper into the face where injection and internal forces are likely to be higher. It is concluded that HA filler gel design can be optimized by use of VOCT to evaluate the % viscous energy loss both in vitro and in vivo. 展开更多
关键词 Hyaluronic Acid Injectable FILLER Dermal FILLER Plastic SURGERY Cosmetic SURGERY VISCOELASTIC Mechanical Properties Facial SURGERY Optical COHERENCE TOMOGRAPHY VIBRATIONAL Optical COHERENCE TOMOGRAPHY
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Proposal to Study Uniqueness Problem of Rayleigh Wave in Half-Space Kelvin Viscoelastic Media 预览
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作者 Hua Cheng Takashi Takiguchi 《应用数学与应用物理(英文)》 2019年第9期2074-2088,共15页
Rayleigh wave is an interference wave of longitudinal wave and transverse wave which propagate along the free surface of solids. There remains a dispute about the number of Rayleigh waves in viscoelastic media until n... Rayleigh wave is an interference wave of longitudinal wave and transverse wave which propagate along the free surface of solids. There remains a dispute about the number of Rayleigh waves in viscoelastic media until now, which is an essential problem of Rayleigh wave propagation. The purpose of this study is to propose a brief way of handling this essential problem within half-space Kelvin viscoelastic media. Starting from the dynamic equations of transverse wave and longitudinal wave based on Kelvin viscoelastic model, this study sets the complex wave number as a variable, introduces complex moduli and complex exponential factors, then a characteristic equation of Kelvin viscoelastic Rayleigh wave in half space is derived and simplified support for analysis of its uniqueness. After reviewing mathematical models describing phenomena of having multiple solutions but uniqueness when a natural condition is taken into account, a conjecture is given that the Rayleigh wave in Kelvin viscoelastic media must be unique if we assume a natural condition in accordance with the natural phenomena. 展开更多
关键词 Rayleigh WAVE VISCOELASTIC WAVE EQUATION Characteristic EQUATION KELVIN Model
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海洋柔性管道用复合材料的粘弹性研究 预览
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作者 黄允灿 韩霞 《船电技术》 2019年第12期24-28,共5页
本文主要研究了柔性管道的结构中起增强作用的增强层材料在长期载荷下的蠕变行为。文中用连续拉挤成型工艺制备了CGFRPP单层板,利用万能力学试验机和DMA测试仪测得了预测模型和理论所需要的力学数据,根据所测得的力学数据分别用Burgers... 本文主要研究了柔性管道的结构中起增强作用的增强层材料在长期载荷下的蠕变行为。文中用连续拉挤成型工艺制备了CGFRPP单层板,利用万能力学试验机和DMA测试仪测得了预测模型和理论所需要的力学数据,根据所测得的力学数据分别用Burgers模型和时间-温度-应力等效原理(TTSSP)预测CGFRPP的长期力学性能,并将两种预测方法所得的结果进行了分析和比较。研究表明TTSSP对CGFRPP复合材料低应力下的蠕变行为预测具有较好的适用性,Burgers粘弹性模型对于CGFRPP复合材料的蠕变行为预测具有良好的适用性。 展开更多
关键词 柔性管道 复合材料 粘弹性
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Direct numerical simulation of the viscoelastic channel flow using Giesekus model with variable parameters 预览
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作者 Wei-guo Gu Yu Li De-zhong Wang 《水动力学研究与进展:英文版》 SCIE EI CSCD 2019年第2期326-332,共7页
The paper presents a direct numerical simulation(DNS)for the drag-reducing channel flow using the Giesekus model with variable parameters.It is assumed that the relaxation time in the constitutive equation is varied d... The paper presents a direct numerical simulation(DNS)for the drag-reducing channel flow using the Giesekus model with variable parameters.It is assumed that the relaxation time in the constitutive equation is varied depending on the local shear rate.The maximal drag reduction rate is obtained when variable parameters are applied in the Giesekus model at a high Weissenberg number.The Reynolds shear stress is reduced when the Weissenberg number increases.In this case,the turbulence generation and transportation are further weakened and increasingly approach to the values in the experiments. 展开更多
关键词 VISCOELASTIC FLUID Giesekus model direct NUMERICAL simulation(DNS) VARIABLE parameters
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变张力轴向运动Rayleigh梁组合参激共振的稳态响应 预览
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作者 王波 钱伟 蒋敏 《机械设计与制造》 北大核心 2019年第6期33-36,41共5页
研究非线性轴向变速黏弹性Rayleigh梁的参激振动问题。梁的本构关系使用Kelvin黏弹性模型描述,并且取全导数。基于广义哈密顿原理,导出轴向运动Rayleigh梁的非线性控制方程。考虑轴向速度在平均速度的基础上有简谐变化。运用直接多尺度... 研究非线性轴向变速黏弹性Rayleigh梁的参激振动问题。梁的本构关系使用Kelvin黏弹性模型描述,并且取全导数。基于广义哈密顿原理,导出轴向运动Rayleigh梁的非线性控制方程。考虑轴向速度在平均速度的基础上有简谐变化。运用直接多尺度法近似求解控制方程,并考虑轴向速度变化频率接近任意两阶固有频率之和时而发生的组合参激共振。依据可解性条件,得到振幅频率方程。通过对数值例子的分析,得到梁的刚度、扭转刚度以及平均速度对稳态响应的影响。 展开更多
关键词 轴向运动Rayleigh梁 黏弹性 多尺度法 组合参数共振 稳态响应
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BLOW-UP OF SOLUTION FOR A VISCOELASTIC WAVE EQUATION WITH DELAY 预览
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作者 吴舜堂 《数学物理学报:B辑英文版》 SCIE CSCD 2019年第1期329-338,共10页
In this paper, we consider the following viscoelastic wave equation with delay|ut|ρutt-△u-△utt+∫0t g(t-8)△u(8)d8 + μ1 ut(x,t) + μ2 ut(x,t-τ) = b|u|p-2 u in a bounded domain. Under appropriate conditions on μ... In this paper, we consider the following viscoelastic wave equation with delay|ut|ρutt-△u-△utt+∫0t g(t-8)△u(8)d8 + μ1 ut(x,t) + μ2 ut(x,t-τ) = b|u|p-2 u in a bounded domain. Under appropriate conditions on μ1, μ2, the kernel function g, the nonlinear source and the initial data, there are solutions that blow up in finite time. 展开更多
关键词 BLOW up nonlinear SOURCE WAVE EQUATION DELAY VISCOELASTIC
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Experimental study on the effects of shear stress on viscoelastic properties of the intestines
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作者 LI Jie BI XiaoNan +2 位作者 ZHANG Ke ZHANG Cheng LIU Hao 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第6期1028-1034,共7页
Shear deformation induced by shear stress is one of the major forms of interaction between the locomotion mechanism and the intestines. Relatively few experimental studies using locomotion mechanisms have been perform... Shear deformation induced by shear stress is one of the major forms of interaction between the locomotion mechanism and the intestines. Relatively few experimental studies using locomotion mechanisms have been performed to investigate the viscoelastic property of intestines. There is a lack of reliable data regarding the relative movement between various locomotion mechanisms and the small intestine, and how that movement affects the measurement of shear displacement. In this work, a novel platform was constructed with two elaborately designed clamps that could securely fix both sides of an intestine sample using negative gas adsorption. The platform was also integrated with noncontact measuring equipment to record the thickness of the intestine sample. Subsequently, preservation measure was applied to porcine intestine, and multiple intestine samples were prepared and tested under strains of 20%, 50%, 80% and 100%. A five-element viscoelastic model that was fitted to multiple sets of data could accurately predict the biomechanical property of the intestines. Finally, a new criterion, the loss factor, was calculated with the parameters of the five-element model to represent the dynamic behavior of soft tissue, and it was used to verify the reliability and effectiveness of the experimental setup and results. 展开更多
关键词 SHEAR stress nonlinear VISCOELASTIC property INTESTINE LOSS factor NEGATIVE gas adsorption
Asymptotic Stability of Memory-Type Euler-Bernoulli Plate with Variable Coefficients and Time Delay
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作者 WANG Peipei HAO Jianghao 《系统科学与复杂性学报:英文版》 CSCD 2019年第5期1375-1392,共18页
This paper considers a viscoelastic Euler-Bernoulli plate system with variable coefficients and time-varying delay. By the multiplier method, Riemannian geometry method, and under suitable assumptions on viscoelastic ... This paper considers a viscoelastic Euler-Bernoulli plate system with variable coefficients and time-varying delay. By the multiplier method, Riemannian geometry method, and under suitable assumptions on viscoelastic term and time delay, the authors obtain the general stability of the solution for the system which depends on the behavior of the relaxation function. 展开更多
关键词 Euler-Bernoulli PLATE general decay rate time-varying DELAY variable coefficients viscoelastic term
A unified poroviscoelastic model with mesoscopic and microscopic heterogeneities
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作者 Boya Zhang Dinghui Yang +1 位作者 Yuanfeng Cheng Yunyin Zhang 《科学通报:英文版》 SCIE EI CSCD 2019年第17期1246-1254,共9页
The wave-induced fluid flow(WIFF) is considered to be the main cause of dispersion and attenuation of seismic waves in fluid-saturated porous media. Among numerous theories, the mesoscopic and microscopic heterogeneit... The wave-induced fluid flow(WIFF) is considered to be the main cause of dispersion and attenuation of seismic waves in fluid-saturated porous media. Among numerous theories, the mesoscopic and microscopic heterogeneities are considered to be the primary mechanisms causing the WIFF. Furthermore,in most rocks, the mesoscopic and microscopic heterogeneities exist simultaneously and can cause obvious transitions of the fast P-wave velocity, which means it is necessary to consider the influence of the two mechanisms on the dispersion and attenuation simultaneously. Numerous results have shown that the dispersions and attenuations caused by these two mechanisms can be approximated in terms of the Zener model. To combine the two mechanisms into a unified model, we introduce a new generalized Zener model into the Biot poroelasticity theory to obtain a new poroviscoelastic model. Comparisons between the numerical results and two groups of experimental data further confirm the validity of our new model. 展开更多
关键词 MESOSCOPIC HETEROGENEITY MICROSCOPIC HETEROGENEITY VISCOELASTIC MODEL Poroviscoelastic MODEL
Extension Omega and Omega-Liutex methods applied to identify vortex structures in viscoelastic turbulent flow 预览
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作者 Lu Wang Zhi-ying Zheng +1 位作者 Wei-hua Cai Wan-you Li 《水动力学研究与进展:英文版》 SCIE EI CSCD 2019年第5期911-921,共11页
The vortex structure plays a significant role in the investigation of the turbulent drag reduction effect of the viscoelastic turbulent flow.This paper aims to find out an optimal vortex identification method for the ... The vortex structure plays a significant role in the investigation of the turbulent drag reduction effect of the viscoelastic turbulent flow.This paper aims to find out an optimal vortex identification method for the viscoelastic turbulent flows,and then studies the turbulent drag reduction mechanism by analyzing the characteristics of the identified vortex structures in the turbulent flows of the viscoelastic fluids.The Q,λ2,Liutex,Omega(Ω)and Omega-Liutex(ΩR)methods are adopted for the identification of vortex structures in the forced homogeneous isotropic turbulence(FHIT)with/without the polymer additive,respectively.The comparison among these five methods shows that the threshold values for the Q,λ2 and Liutex methods should be specially adjusted so as to suitably describe the strong and weak vortex structures in the FHIT of both the Newtonian and viscoelastic fluids,while a fixed threshold value of 0.52 for theΩandΩR methods is effective for both the Newtonian and viscoelastic fluids.The comparison between the identified vortex structures in the FHIT with and without the polymer additive indicates that theΩandΩR methods are more appropriate for the vortex identification because their dimensionless values with a fixed range from 0 to 1 can avoid the effect of the different ranges of the Q,λ2 and∣R∣(for the Liutex method)for the Newtonian and viscoelastic fluids.This also illustrates that theΩandΩR methods can be extended to identify the vortex structures in the turbulent flow of the viscoelastic fluid.Finally,the characteristics of the vortex structures in the FHIT of the viscoelastic fluid are analyzed by utilizing theΩandΩR methods.The results show that both the strong and weak vortex structures are inhibited by increasing the concentration of the polymer solution and by decreasing the Weissenberg number,especially for the weak vortex structures. 展开更多
关键词 Vortex identification Omega method(Ω) Omega-Liutex(ΩR)method forced homogeneous isotropic turbulence viscoelastic fluid
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考虑黏弹性的簧片单元力学性能分析 预览
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作者 叶红玲 史雪松 张洋 《北京工业大学学报》 CAS CSCD 北大核心 2019年第3期275-282,共8页
为提高空间可展簧片铰链的运行稳定性和可靠性,研究了材料黏弹性对其弯曲折叠过程中的应变能、临界弯矩和稳态弯矩的影响.利用广义Maxwell黏弹性模型建立了考虑黏弹性的簧片单元力学模型,采用数值模拟方法探究了外界温度、折叠速率、Pr... 为提高空间可展簧片铰链的运行稳定性和可靠性,研究了材料黏弹性对其弯曲折叠过程中的应变能、临界弯矩和稳态弯矩的影响.利用广义Maxwell黏弹性模型建立了考虑黏弹性的簧片单元力学模型,采用数值模拟方法探究了外界温度、折叠速率、Prony常数、松弛时间对簧片单元应变能、临界弯矩和稳态弯矩的影响规律.结果表明:在折叠过程中,随着Prony常数,松弛时间和折叠速度的减小,簧片单元应变能、临界弯矩和稳态弯矩均有所减小.随着温度的增加,簧片单元应变能、临界弯矩和稳态弯矩均呈现不同程度的减小.在装载过程中,簧片单元的稳态弯矩和应变能随着装载时间的增加而减小并趋于稳定.本研究对于提高空间可展结构的设计可靠性提供了一定的依据. 展开更多
关键词 簧片单元 黏弹性 力学性能 数值仿真 稳定性 可靠性
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低浮纤GFRPP复合材料的流变性能分析
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作者 于相慧 徐培琦 +2 位作者 曲敏杰 王书唯 张勇杰 《塑料科技》 CAS 北大核心 2019年第10期66-69,共4页
采用包覆工艺制备了聚丁烯-1/玻璃纤维(PB-1/GF)母粒,与聚丙烯(PP)等熔融共混制备了玻纤增强聚丙烯(GFRPP)复合材料,并在200℃下分析了复合材料的静态和动态黏弹性。结果表明:复合材料的剪切黏度随着剪切速率的增大呈现出线性降低的趋... 采用包覆工艺制备了聚丁烯-1/玻璃纤维(PB-1/GF)母粒,与聚丙烯(PP)等熔融共混制备了玻纤增强聚丙烯(GFRPP)复合材料,并在200℃下分析了复合材料的静态和动态黏弹性。结果表明:复合材料的剪切黏度随着剪切速率的增大呈现出线性降低的趋势。当PB-1用量为10%时,复合材料具有较高流动性。复合材料有很强的频率依赖性,在低频区,材料显示出黏性的特点;在高频区,材料则表现出橡胶弹性的特点。 展开更多
关键词 玻纤增强聚丙烯 流动性 频率 黏弹性
橡胶超弹-黏弹模型建立及结构动态响应 预览
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作者 初红艳 孙冬明 +1 位作者 陈其 蔡力钢 《北京工业大学学报》 CAS CSCD 北大核心 2019年第10期927-936,共10页
为了研究橡胶结构的动态响应,需要准确建立本构模型.通过动态热机械分析仪(dynamic thermomechani-cal analysis,DMA)测试圆盘形橡胶试样,获得橡胶黏弹因子、储能模量、损耗模量等力学数据,建立超弹-黏弹本构模型,超弹模型表征橡胶的大... 为了研究橡胶结构的动态响应,需要准确建立本构模型.通过动态热机械分析仪(dynamic thermomechani-cal analysis,DMA)测试圆盘形橡胶试样,获得橡胶黏弹因子、储能模量、损耗模量等力学数据,建立超弹-黏弹本构模型,超弹模型表征橡胶的大变形特性,黏弹模型表征橡胶的滞后效应,其中黏弹模型参数是通过利用 ANSYS 拟合 DMA 实验所得松弛曲线数据获得,超弹模型参数是通过利用经验公式辨识得到.建立与实验条件一致的动力学仿真模型,实验数据与仿真数据的误差较小,在合理范围内,验证了通过上述方法辨识模型参数所建立超弹-黏弹本构模型的正确性.仿真获得了圆盘形橡胶试样、立方块橡胶试样分别在周期性扭转载荷和垂直载荷作用下的应力、应变、损耗等响应特性,并验证了所建立本构模型的适用性.通过研究立方块橡胶试样在超弹-黏弹本构模型、线弹-黏弹本构模型、单一的超弹本构模型下的动态响应特性,表明了本构模型的选择对橡胶结构动态响应分析的重要性,为工程实际问题中橡胶本构模型的选择提供参考. 展开更多
关键词 橡胶 黏弹性 超弹性 参数辨识 本构模型 滞后特性
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黏弹性正交各向异性空心圆柱中纵向导波的传播
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作者 李思宇 张宇 +3 位作者 刘宏业 范彦平 吕炎 刘增华 《复合材料学报》 EI CAS CSCD 北大核心 2019年第10期2275-2285,共11页
基于线性三维弹性理论和Kelvin-Voigt模型,采用勒让德正交多项式展开法推导了黏弹性正交各向异性空心圆柱中纵向导波的波动方程,数值求解了波动方程并阐述了相关方程的含义。首先计算了大径厚比下黏弹性管的相速度频散曲线和衰减曲线,... 基于线性三维弹性理论和Kelvin-Voigt模型,采用勒让德正交多项式展开法推导了黏弹性正交各向异性空心圆柱中纵向导波的波动方程,数值求解了波动方程并阐述了相关方程的含义。首先计算了大径厚比下黏弹性管的相速度频散曲线和衰减曲线,并与已发表文献的结果进行了对比,验证了程序的正确性,并进一步计算了低阶纵向导波的位移分布和应力分布曲线,验证了方法的可靠性。然后利用方程的解耦特性,分别求解了不同径厚比、不同黏性常数下纵向模态和扭转模态的频散和衰减曲线,研究了径厚比和黏性常数效应对两种模态的影响。最后针对扭转模态导波,研究了材料相关黏弹性常数对其频散特性和衰减特性的影响。 展开更多
关键词 正交多项式 纵向导波 黏弹性 频散曲线 衰减曲线
粘弹性材料动态体积模量测试方法研究进展
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作者 张栋洋 李登峰 王兵 《材料开发与应用》 CAS 2019年第1期106-112,共7页
分析了国内外相关文献,对目前粘弹性材料动态体积模量的测试方法进行了总结,并对未来测试技术的发展进行了简单展望。
关键词 粘弹性 体积模量 声学性能 测试方法
Seismic performance evaluation of typical dampers designed by Chinese building code 预览
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作者 Guo Wei Wu Jun +2 位作者 Hu Yao Li Yunsong Yang T.Y. 《地震工程与工程振动:英文版》 SCIE EI CSCD 2019年第2期433-446,共14页
Adding dampers is a commonly adopted seismic risk mitigation strategy for modern buildings, and the corresponding design procedure of dampers has been well established by the Chinese Building Code. Even though all typ... Adding dampers is a commonly adopted seismic risk mitigation strategy for modern buildings, and the corresponding design procedure of dampers has been well established by the Chinese Building Code. Even though all types of dampers are designed by the same procedure, actual seismic performance of the building may differ from one to the others. In this study, a nine-story benchmark steel building is established, and three different and typical types of dampers are designed according to the Chinese Building Code to realize structural vibration control under strong earthquake excitation. The seismic response of the prototype building equipped with a viscoelastic damper, viscous damper and buckling-restrained brace(BRB) subjected to 10 earthquake records are calculated, and Incremental Dynamic Analysis(IDA) is performed to describe progressive damage of the structure under increasing earthquake intensity. In the perspective of fragility, it shows that the viscoelastic damper has the highest collapse margin ratio(CMR), and the viscous damper provides the best drift control. Both the BRB and viscoelastic dampers can effectively reduce the floor acceleration responses in the mid-rise building. 展开更多
关键词 CHINESE building design code viscoelastic DAMPER VISCOUS DAMPER buckling-restrained BRACE seismic response FRAGILITY analysis
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Stationary response of stochastic viscoelastic system with the right unilateral nonzero offset barrier impacts
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作者 王德莉 徐伟 谷旭东 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第1期195-204,共10页
The stationary response of viscoelastic dynamical system with the right unilateral nonzero offset barrier impacts subjected to stochastic excitations is investigated. First, the viscoelastic force is approximately tre... The stationary response of viscoelastic dynamical system with the right unilateral nonzero offset barrier impacts subjected to stochastic excitations is investigated. First, the viscoelastic force is approximately treated as equivalent terms associated with effects. Then, the free vibro-impact(VI) system is absorbed to describe the periodic motion without impacts and quasi-periodic motion with impacts based upon the level of system energy. The stochastic averaging of energy envelope(SAEE) is adopted to seek the stationary probability density functions(PDFs). The detailed theoretical results for Van der Pol viscoelastic VI system with the right unilateral nonzero offset barrier are solved to demonstrate the important effects of the viscoelastic damping and nonzero rigid barrier impacts condition. Monte Carlo(MC) simulation is also performed to verify the reliability of the suggested approach. The stochastic P-bifurcation caused by certain system parameters is further explored. The variation of elastic modulus from negative to zero and then to positive witnesses the evolution process of stochastic P-bifurcation. From the vicinity of the common value to a wider range, the relaxation time induces the stochastic P-bifurcation in the two interval schemes. 展开更多
关键词 viscoelastic system RIGHT UNILATERAL nonzero offset BARRIER IMPACTS STOCHASTIC AVERAGING of energy envelope(SAEE) STOCHASTIC P-bifurcation
变密度自增稠支撑剂制备及其性能评价 预览
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作者 郐婧文 陈清 +2 位作者 孟祥海 张云宝 王楠 《化学工程师》 CAS 2019年第3期31-36,共6页
为满足矿场压裂施工技术需求,本文采用将聚合物细粉黏附在支撑剂颗粒外表面的方法,制作了变密度自增稠支撑剂,并对其进行性能评价。结果表明,在支撑剂粒径一定条件下,当黏附比(聚合物:支撑剂)为6.6%时,支撑剂视密度变化率接近30%。当砂... 为满足矿场压裂施工技术需求,本文采用将聚合物细粉黏附在支撑剂颗粒外表面的方法,制作了变密度自增稠支撑剂,并对其进行性能评价。结果表明,在支撑剂粒径一定条件下,当黏附比(聚合物:支撑剂)为6.6%时,支撑剂视密度变化率接近30%。当砂比≥20%后,大庆油田清水、长庆油田注入水、大港油田注入水配制变密度自增稠支撑剂的沉降时间均大于240min。采用大庆油田清水复配“变密度自增稠支撑剂+普通陶粒支撑剂”压裂液,当“变密度自增稠支撑剂:支撑剂”大于4∶1后,可在240min内不发生沉降。温度对抗盐聚合物溶液的流变性和粘弹性影响均较小。在振荡频率一定的条件下,随着配制水矿化度增大,抗盐聚合物溶液的储能模量和损耗模量减小。 展开更多
关键词 陶粒 黏结剂 聚合物 支撑剂 悬砂时间 流变性 粘弹性
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A GENERAL DECAY AND OPTIMAL DECAY RESULT IN A HEAT SYSTEM WITH A VISCOELASTIC TERM 预览
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作者 Abderrahmane YOUKANA Salim A. MESSAOUDI Aissa GUESMIA 《数学物理学报:B辑英文版》 SCIE CSCD 2019年第2期618-626,共9页
We consider a quasilinear heat system in the presence of an integral term and establish a general and optimal decay result from which improves and generalizes several stability results in the literature.
关键词 heat EQUATION VISCOELASTIC general DECAY OPTIMAL
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带式输送机输送带张紧力检测装置的设计与测试 预览
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作者 张黎军 《机械管理开发》 2019年第8期17-19,共3页
为了更好地进行带式输送机的设计,对输送带张紧力的变化趋势进行了研究,避免设计张紧力过大时出现带式输送机滚筒及机架较大而造成浪费、张紧力过小时不能保证物料的平稳输送的问题,采用称重式传感器设计了张紧力的检测装置,并将其应用... 为了更好地进行带式输送机的设计,对输送带张紧力的变化趋势进行了研究,避免设计张紧力过大时出现带式输送机滚筒及机架较大而造成浪费、张紧力过小时不能保证物料的平稳输送的问题,采用称重式传感器设计了张紧力的检测装置,并将其应用于伸缩式带式输送机上进行张紧力的检测,以期为带式输送机张紧力的研究提供依据,为带式输送机的改进设计提供参考。 展开更多
关键词 带式输送机 输送带 黏弹性 张紧力
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