A novel method of controlling the shape memory properties of shape memory polyurethane （SMPU） by addition of micro-phase separation promoters including 1-octadecanol （ODO） and liquid paraffin （LP） is reported. T...A novel method of controlling the shape memory properties of shape memory polyurethane （SMPU） by addition of micro-phase separation promoters including 1-octadecanol （ODO） and liquid paraffin （LP） is reported. The results indicate that the strain recovery temperature and the strain modulus rate （Eg/Er） were increased significantly with addition of small amount of micro-phase separation promoters. Thus it can increase the shape memory fixity rate and other shape memory behaviors of SMPU.展开更多
Sub-micron sized phenolic epoxy resin waterborne particles were prepared by phase inversion emulsification. Micro-phase separation occurred during the curing process at high temperature. The as-prepared samples posses...Sub-micron sized phenolic epoxy resin waterborne particles were prepared by phase inversion emulsification. Micro-phase separation occurred during the curing process at high temperature. The as-prepared samples possessed one glass transition temperature （Tg） and two exothermal processes during DSC heating scannings. After being thermally treated above the exothermal peak temperature, they possessed two glass transition temperatures with the disappearance of exothermal peaks, whilst a core/shell structure was formed. This was likely related with the outward diffusion of reactive oligomers to the outer layer of particles.展开更多
In the process of geologic prospecting and development, it is important to forecast the distribution of gritstone, master the regulation of physical parameter in the reserves mass level. Especially, it is more importa...In the process of geologic prospecting and development, it is important to forecast the distribution of gritstone, master the regulation of physical parameter in the reserves mass level. Especially, it is more important to recognize to rock phase and sedimentary circumstance. In the land level, the study of sedimentary phase and micro-phase is important to prospect and develop. In this paper, an automatic approach based on ANN (Artificial Neural Networks) is proposed to recognize sedimentary phase, the corresponding system is designed after the character of well general curves is considered. Different from the approach extracting feature parameters, the proposed approach can directly process the input curves. The proposed method consists of two steps: The first step is called learning. In this step, the system creates automatically sedimentary micro-phase features by learning from the standard sedimentary micro-phase patterns such as standard electric current phase curves of the well and standard resistance rate curves of the well. The second step is called recognition. In this step, based the results of the learning step, the system classifies automatically by comparing the standard pattern curves of the well to unknown pattern curves of the well. The experiment has demonstrated that the proposed approach is more effective than those approaches used previously.展开更多
Self-organization in thin micro-films has shown potential for the production of microelements with specific structures and functions; however, little is known about its mechanism of formation. A 2-D molecular dynamics...Self-organization in thin micro-films has shown potential for the production of microelements with specific structures and functions; however, little is known about its mechanism of formation. A 2-D molecular dynamics (MD) simulation on this process is carried out in this paper for films between two parallel walls (substrates) under different initial conditions. The films consist of two immiscible components (A and B). The simulation results in alternative columns perpendicular to the walls, which are rich either in A or in B molecules, respectively, apparently owing to their different interactions with the walls. The characteristic breadths of the columns depend on the distance between the two walls. By providing microscopic details of the self-organization processes and the resulted structures, MD simulation proves itself as a unique way for analyzing the dynamics of thin films.展开更多
针对微特电机驱动控制系统中,双有源桥(dual active bridge,DAB)变换器在高频调制过程中易产生较大电流应力,导致器件温升高、寿命衰减及负载扰动下系统稳定性下降等问题,本文提出一种改进型双移相优化调制策略。该方法基于双有源桥拓扑...针对微特电机驱动控制系统中,双有源桥(dual active bridge,DAB)变换器在高频调制过程中易产生较大电流应力,导致器件温升高、寿命衰减及负载扰动下系统稳定性下降等问题,本文提出一种改进型双移相优化调制策略。该方法基于双有源桥拓扑,建立双移相调制下的功率传输模型与电流应力数学模型,采用拉格朗日乘数法求解最优移相比组合,并进一步推导多功率场景下的电流应力解析表达式;在控制器设计方面,引入电感电流内环补偿机制,提高系统对电机驱动过程中负载变化的动态响应能力。MATLAB/Simulink仿真结果表明,该方法在典型微特电机负载工况下能有效降低变换器的电流应力,缩短暂态响应时间,并改善输出电压纹波,对提升微特电机控制系统的稳态与暂态性能具有良好效果,为高效能电机驱动供电模块的优化设计提供理论依据。展开更多
Silicon suboxide(SiO_(x),0<x<2)is an appealing anode material to replace traditional graphite owing to its much higher theoretical specific capacity enabling higher-energy-density lithium batteries.Nevertheless,...Silicon suboxide(SiO_(x),0<x<2)is an appealing anode material to replace traditional graphite owing to its much higher theoretical specific capacity enabling higher-energy-density lithium batteries.Nevertheless,the huge volume change and rapid capacity decay of SiO_(x)electrodes during cycling pose huge challenges to their large-scale practical applications.To eliminate this bottleneck,a dragonfly wing microstructure-inspired polymer electrolyte(denoted as PPM-PE)is developed based on in-situ polymerization of bicyclic phosphate ester-and urethane motif-containing monomer and methyl methacrylate in traditional liquid electrolyte.PPM-PE delivers excellent mechanical properties,highly correlated with the formation of a micro-phase separation structure similar with dragonfly wings.By virtue of superior mechanical properties and the in-situ solidified preparation method,PPM-PE can form a 3D polymer network buffer against stress within the electrode particles gap,enabling much suppressed electrode volume expansion and more stabilized solid electrolyte interface along with evidently decreased electrolyte decomposition.Resultantly,PPM-PE shows significant improvements in both cycling and rate performance in button and soft package batteries with SiO_(x)-based electrodes,compared with the liquid electrolyte counterpart.Such a dragonfly wing microstructure-inspired design philosophy of in-situ solidified polymer electrolytes helps facilitate the practical implementation of high-energy lithium batteries with SiO_(x)-based anodes.展开更多
基金We are grateful to the Natural Science Foundation of Hunan Province(Project no.01JJY33011)for financial support for this work.We also thank Dr.Yuan Li Cai for his assistance.
文摘A novel method of controlling the shape memory properties of shape memory polyurethane （SMPU） by addition of micro-phase separation promoters including 1-octadecanol （ODO） and liquid paraffin （LP） is reported. The results indicate that the strain recovery temperature and the strain modulus rate （Eg/Er） were increased significantly with addition of small amount of micro-phase separation promoters. Thus it can increase the shape memory fixity rate and other shape memory behaviors of SMPU.
基金This work was financially supported by the National Natural Science Foundation of China(No.20104008).
文摘Sub-micron sized phenolic epoxy resin waterborne particles were prepared by phase inversion emulsification. Micro-phase separation occurred during the curing process at high temperature. The as-prepared samples possessed one glass transition temperature （Tg） and two exothermal processes during DSC heating scannings. After being thermally treated above the exothermal peak temperature, they possessed two glass transition temperatures with the disappearance of exothermal peaks, whilst a core/shell structure was formed. This was likely related with the outward diffusion of reactive oligomers to the outer layer of particles.
文摘In the process of geologic prospecting and development, it is important to forecast the distribution of gritstone, master the regulation of physical parameter in the reserves mass level. Especially, it is more important to recognize to rock phase and sedimentary circumstance. In the land level, the study of sedimentary phase and micro-phase is important to prospect and develop. In this paper, an automatic approach based on ANN (Artificial Neural Networks) is proposed to recognize sedimentary phase, the corresponding system is designed after the character of well general curves is considered. Different from the approach extracting feature parameters, the proposed approach can directly process the input curves. The proposed method consists of two steps: The first step is called learning. In this step, the system creates automatically sedimentary micro-phase features by learning from the standard sedimentary micro-phase patterns such as standard electric current phase curves of the well and standard resistance rate curves of the well. The second step is called recognition. In this step, based the results of the learning step, the system classifies automatically by comparing the standard pattern curves of the well to unknown pattern curves of the well. The experiment has demonstrated that the proposed approach is more effective than those approaches used previously.
文摘Self-organization in thin micro-films has shown potential for the production of microelements with specific structures and functions; however, little is known about its mechanism of formation. A 2-D molecular dynamics (MD) simulation on this process is carried out in this paper for films between two parallel walls (substrates) under different initial conditions. The films consist of two immiscible components (A and B). The simulation results in alternative columns perpendicular to the walls, which are rich either in A or in B molecules, respectively, apparently owing to their different interactions with the walls. The characteristic breadths of the columns depend on the distance between the two walls. By providing microscopic details of the self-organization processes and the resulted structures, MD simulation proves itself as a unique way for analyzing the dynamics of thin films.
文摘针对微特电机驱动控制系统中,双有源桥(dual active bridge,DAB)变换器在高频调制过程中易产生较大电流应力,导致器件温升高、寿命衰减及负载扰动下系统稳定性下降等问题,本文提出一种改进型双移相优化调制策略。该方法基于双有源桥拓扑,建立双移相调制下的功率传输模型与电流应力数学模型,采用拉格朗日乘数法求解最优移相比组合,并进一步推导多功率场景下的电流应力解析表达式;在控制器设计方面,引入电感电流内环补偿机制,提高系统对电机驱动过程中负载变化的动态响应能力。MATLAB/Simulink仿真结果表明,该方法在典型微特电机负载工况下能有效降低变换器的电流应力,缩短暂态响应时间,并改善输出电压纹波,对提升微特电机控制系统的稳态与暂态性能具有良好效果,为高效能电机驱动供电模块的优化设计提供理论依据。
基金financially supported by the National Key R&D Program of China(2023YFC2812700)the Key Scientific and Technological Innovation Project of Shandong(2022CXGC020301)+6 种基金the National Natural Science Foundation of China(22279153,U22A2044,22479154,52303287)the Taishan Scholars of Shandong Province(No.ts201511063)the Shandong Energy Institute(Grant No.SEI I202108)the Postdoctoral Fellowship Program of CPSF(E31Z3F04)China Postdoctoral Science Foundation(2024 M753350)the Natural Science Foundation of Shandong Province(ZR2023QB208)Qingdao Natural Science Foundation(23-2-1-77-zyyd-jch)。
文摘Silicon suboxide(SiO_(x),0<x<2)is an appealing anode material to replace traditional graphite owing to its much higher theoretical specific capacity enabling higher-energy-density lithium batteries.Nevertheless,the huge volume change and rapid capacity decay of SiO_(x)electrodes during cycling pose huge challenges to their large-scale practical applications.To eliminate this bottleneck,a dragonfly wing microstructure-inspired polymer electrolyte(denoted as PPM-PE)is developed based on in-situ polymerization of bicyclic phosphate ester-and urethane motif-containing monomer and methyl methacrylate in traditional liquid electrolyte.PPM-PE delivers excellent mechanical properties,highly correlated with the formation of a micro-phase separation structure similar with dragonfly wings.By virtue of superior mechanical properties and the in-situ solidified preparation method,PPM-PE can form a 3D polymer network buffer against stress within the electrode particles gap,enabling much suppressed electrode volume expansion and more stabilized solid electrolyte interface along with evidently decreased electrolyte decomposition.Resultantly,PPM-PE shows significant improvements in both cycling and rate performance in button and soft package batteries with SiO_(x)-based electrodes,compared with the liquid electrolyte counterpart.Such a dragonfly wing microstructure-inspired design philosophy of in-situ solidified polymer electrolytes helps facilitate the practical implementation of high-energy lithium batteries with SiO_(x)-based anodes.
