This page has only limited features, please log in for full access.
Improving the trade-off between accuracy and interpretability is essential for the problem of handling high-dimensional data in Takagi-Sugeno-Kang (TSK) fuzzy systems and providing insights into real-world tasks. However, the TSK fuzzy system becomes complex and challenging to interpret as the data dimension increases. Here, we report an ensemble classifier, which is an enhanced adaptive network-based fuzzy inference system (ANFIS) integrating improved bagging and dropout to build concise fuzzy rule sets. First, the high-dimensional feature space is decomposed into a series of low-dimensional feature subsets using the bagging and random subspace method to train multiple ANFISs. An improved dropout strategy is then applied in training ANFISs by temporarily disabling rules in each training epoch and deleting rules after training to obtain sparse rulesets with high-quality rules. These sub-models are subsequently aggregated to perform the fuzzy inference. Results on high-dimensional benchmark datasets confirm that both the bagging and dropout strategies are effective, providing high interpretability by reducing the co-firing degrees and rules of sub-models while guaranteeing accuracy at the same time.
Fei Guo; Jiahuan Liu; Maoyuan Li; Tianlun Huang; Yun Zhang; Dequn Li; Huamin Zhou. A Concise TSK Fuzzy Ensemble Classifier Integrating Dropout and Bagging for High-dimensional Problems. IEEE Transactions on Fuzzy Systems 2021, PP, 1 -1.
AMA StyleFei Guo, Jiahuan Liu, Maoyuan Li, Tianlun Huang, Yun Zhang, Dequn Li, Huamin Zhou. A Concise TSK Fuzzy Ensemble Classifier Integrating Dropout and Bagging for High-dimensional Problems. IEEE Transactions on Fuzzy Systems. 2021; PP (99):1-1.
Chicago/Turabian StyleFei Guo; Jiahuan Liu; Maoyuan Li; Tianlun Huang; Yun Zhang; Dequn Li; Huamin Zhou. 2021. "A Concise TSK Fuzzy Ensemble Classifier Integrating Dropout and Bagging for High-dimensional Problems." IEEE Transactions on Fuzzy Systems PP, no. 99: 1-1.
Entanglement network is an important structural feature in concentrated polymer solutions and polymer melts, which has a great influence on the transient rheological behavior and molecular configuration evolution. However, the existing constitutive models have limitations in describing the influence of dynamic entanglement behavior on molecular chain motion, resulting in inaccurate descriptions of the transient rheological behavior. Thus, a molecular configuration evolution model for polymer solutions considering the dynamic entanglement effect is proposed by introducing an intermolecular force that changes with the orientation of the molecular chain in this work. The intermolecular force is introduced by considering the friction coefficient as anisotropic, and the orientation effect is considered by introducing an excluded volume dependent anisotropic diffusion. The proposed model can better describe the stress relaxation, stress growth, and dielectric anisotropy of polymer solutions compared with the anisotropy FENE model and FENE model. In addition, the influence of different model parameters on the transient and steady shear response of polymer solution is investigated, and the results show that the influence of volume loss on the friction anisotropy factor kσ increases as the solution concentration increases.
Wen-Jie Yu; Guan-Cheng Shen; Xiao-Wei Zhou; Mao-Yuan Li; Yun Zhang; Hua-Min Zhou; De-Qun Li. A Constitutive Model Describing Molecular Configuration Evolution and Transient Rheological Behavior of Entangled Polymer Solutions. Chinese Journal of Polymer Science 2021, 1 -15.
AMA StyleWen-Jie Yu, Guan-Cheng Shen, Xiao-Wei Zhou, Mao-Yuan Li, Yun Zhang, Hua-Min Zhou, De-Qun Li. A Constitutive Model Describing Molecular Configuration Evolution and Transient Rheological Behavior of Entangled Polymer Solutions. Chinese Journal of Polymer Science. 2021; ():1-15.
Chicago/Turabian StyleWen-Jie Yu; Guan-Cheng Shen; Xiao-Wei Zhou; Mao-Yuan Li; Yun Zhang; Hua-Min Zhou; De-Qun Li. 2021. "A Constitutive Model Describing Molecular Configuration Evolution and Transient Rheological Behavior of Entangled Polymer Solutions." Chinese Journal of Polymer Science , no. : 1-15.
Fused Filament Fabrication (FFF) is one of the most widely used material extrusion additive manufacturing techniques. Its application is limited by the poor mechanical properties because of the weak bonding interface between strands. Although numerous experimental studies have investigated the effects of process parameters on mechanical performances, the bonding fracture mechanism and the quantitative relationship between process parameters and the bonding strength are not well understood. Here, we report a novel theoretical model considering coupled effects of the bonding interface evolution and molecular diffusion for predicting the bonding strength, which provides a comprehensive insight into the FFF bonding process. The model establishes an accurate relationship between process parameters and the bonding strength parallel/perpendicular to the deposition direction. Predictions agree well with experimental results and the average root mean square error (RMS) is ~5.52%. The fracture mechanism confirms the variation of the bonding interface and molecular diffusion assumed in the model. The bonding interface evolution and molecular diffusion are proved to play an important role in the bonding strength.
Mengyuan Zhou; Xiaowei Zhou; Liang Si; Peng Chen; Maoyuan Li; Yun Zhang; Huamin Zhou. Modeling of bonding strength for Fused Filament Fabrication considering bonding interface evolution and molecular diffusion. Journal of Manufacturing Processes 2021, 68, 1485 -1494.
AMA StyleMengyuan Zhou, Xiaowei Zhou, Liang Si, Peng Chen, Maoyuan Li, Yun Zhang, Huamin Zhou. Modeling of bonding strength for Fused Filament Fabrication considering bonding interface evolution and molecular diffusion. Journal of Manufacturing Processes. 2021; 68 ():1485-1494.
Chicago/Turabian StyleMengyuan Zhou; Xiaowei Zhou; Liang Si; Peng Chen; Maoyuan Li; Yun Zhang; Huamin Zhou. 2021. "Modeling of bonding strength for Fused Filament Fabrication considering bonding interface evolution and molecular diffusion." Journal of Manufacturing Processes 68, no. : 1485-1494.
The uneven temperature field caused by the local instantaneous heating of the laser generates the thermal stress during the selective laser sintering. The stress causes the deformation of parts, affecting the precision and mechanical properties. However, it's difficult to directly measure the stress history and deformation behavior during processing through experimental methods due to its ultra-high temperature and closed cavity. In this paper, the effects of laser power and scanning speed on the stress field and deformation of polyamide 6 by selective laser sintering were systematically investigated. The results showed that as the laser power increased or the scanning speed decreased, the z-direction stress and deformation of the specimens increased. Based on the inherent strain method, the deformation behavior of large-size parts was evaluated and in good agreement with experiments, which can guarantee the accuracy of the model and predict the deformation of parts.
Mengyuan Zhou; Yuchen Han; Liang Si; Maoyuan Li. Experimental investigation and numerical simulation of the stress and deformation behavior for selective laser sintering of PA6. Journal of Physics: Conference Series 2021, 1820, 012088 .
AMA StyleMengyuan Zhou, Yuchen Han, Liang Si, Maoyuan Li. Experimental investigation and numerical simulation of the stress and deformation behavior for selective laser sintering of PA6. Journal of Physics: Conference Series. 2021; 1820 (1):012088.
Chicago/Turabian StyleMengyuan Zhou; Yuchen Han; Liang Si; Maoyuan Li. 2021. "Experimental investigation and numerical simulation of the stress and deformation behavior for selective laser sintering of PA6." Journal of Physics: Conference Series 1820, no. 1: 012088.
Carbon-coated silicon nanotube ([email protected]) anodes show tremendous potential in high-performance lithium ion batteries (LIBs). Unfortunately, to realize the commercial application, it is still required to further optimize the structural design for better durability and safety. Here, the electrochemical and mechanical evolution in lithiated [email protected] nanohybrids are investigated using large-scale atomistic simulations. More importantly, the lithiation responses of [email protected] nanohybrids are also investigated in the same simulation conditions as references. The simulations quantitatively reveal that the inner hole of the SiNT alleviates the compressive stress concentration between a-Li x Si and C phases, resulting in the [email protected] having a higher Li capacity and faster lithiation rate than [email protected] The contact mode significantly regulates the stress distribution at the inner hole surface, further affecting the morphological evolution and structural stability. The inner hole of bare SiNT shows good structural stability due to no stress concentration, while that of concentric [email protected] undergoes dramatic shrinkage due to compressive stress concentration, and that of eccentric [email protected] is deformed due to the mismatch of stress distribution. These findings not only enrich the atomic understanding of the electrochemical–mechanical coupled mechanism in lithiated [email protected] nanohybrids but also provide feasible solutions to optimize the charging strategy and tune the nanostructure of SiNT-based electrode materials.
Chen Feng; Shiyuan Liu; Junjie Li; Maoyuan Li; Siyi Cheng; Chen Chen; Tielin Shi; Zirong Tang. Molecular Understanding of Electrochemical–Mechanical Responses in Carbon-Coated Silicon Nanotubes during Lithiation. Nanomaterials 2021, 11, 564 .
AMA StyleChen Feng, Shiyuan Liu, Junjie Li, Maoyuan Li, Siyi Cheng, Chen Chen, Tielin Shi, Zirong Tang. Molecular Understanding of Electrochemical–Mechanical Responses in Carbon-Coated Silicon Nanotubes during Lithiation. Nanomaterials. 2021; 11 (3):564.
Chicago/Turabian StyleChen Feng; Shiyuan Liu; Junjie Li; Maoyuan Li; Siyi Cheng; Chen Chen; Tielin Shi; Zirong Tang. 2021. "Molecular Understanding of Electrochemical–Mechanical Responses in Carbon-Coated Silicon Nanotubes during Lithiation." Nanomaterials 11, no. 3: 564.
During the selective laser sintering process, the sintering behavior between powders is mainly affected by thermal effect. There are a large number of process parameters influencing the variation of temperature and molten pool, of which the laser density and scanning speed play a crucial role in determining the performance of the parts. In this paper, the effects of laser density and scanning speed on the precision and strength of polyamide 6 selective laser sintering parts were systematically investigated. The results show that with the increase of energy density, the positive dimensional deviation of the parts in three directions increases gradually, and the tensile strength increases at beginning and then decreases. When the laser power and scanning speed were changed, the tensile strength of the parts varied between 5.62 MPa and 58.74 MPa.
Liang Si; Yuchen Han; Mengyuan Zhou; Maoyuan Li. The influence of process parameters on the performance of nylon 6 selective laser sintering parts. Journal of Physics: Conference Series 2021, 1798, 012021 .
AMA StyleLiang Si, Yuchen Han, Mengyuan Zhou, Maoyuan Li. The influence of process parameters on the performance of nylon 6 selective laser sintering parts. Journal of Physics: Conference Series. 2021; 1798 (1):012021.
Chicago/Turabian StyleLiang Si; Yuchen Han; Mengyuan Zhou; Maoyuan Li. 2021. "The influence of process parameters on the performance of nylon 6 selective laser sintering parts." Journal of Physics: Conference Series 1798, no. 1: 012021.
High-precision aspheric negative plastic lenses are widely used in optical systems owing to their excellent performance and ease of high-efficiency manufacturing. The imaging performance of the lens is difficult to control, because it is unable to perform optical measurements directly and is sensitive to manufacturing processing meanwhile. Generally, the imaging performance is guaranteed by a strict control of geometrical deviation, such as Peak-to-Valley (PV) and Root-Mean-Square (RMS). In this study, an optical ray-tracing algorithm with the measured geometrical deviation data is proposed to perform an imaging performance analysis correlated with geometrical deviation for the injection molded high-precision aspheric negative plastic lens. Taguchi experiments are applied to investigating the effect of processing parameters. The geometrical deviation of the convex surface is found to be an order of magnitude greater than that of the concave surface. The geometrical dimension of the concave surface is mainly determined by the machining precision of the mold cavity surface, whereas the convex surface dimension is mainly affected by the lens shrinkage. However, the imaging performance has a nonlinear correlation with the geometrical deviation. Modulation Transfer Function (MTF) and Spot Diagram are equivalently affected by the concave and convex geometrical deviations, and depend on the object field height. The effect of processing parameters on geometrical deviation and imaging performance is uncorrelated. Thus, the imaging performance should be simultaneously considered as a criterion as well as the geometrical deviation in the optimization of aspheric negative lens injection molding processing. The imaging performance prediction using an optical ray-tracing algorithm with the measured geometrical deviation data is instrumental to optimize the manufacturing processing.
Xiaowei Zhou; Yun Zhang; Wenjie Yu; Maoyuan Li; Yuhong Chen; Huamin Zhou. An imaging performance analysis method correlated with geometrical deviation for the injection molded high-precision aspheric negative plastic lens. Journal of Manufacturing Processes 2020, 58, 1115 -1125.
AMA StyleXiaowei Zhou, Yun Zhang, Wenjie Yu, Maoyuan Li, Yuhong Chen, Huamin Zhou. An imaging performance analysis method correlated with geometrical deviation for the injection molded high-precision aspheric negative plastic lens. Journal of Manufacturing Processes. 2020; 58 ():1115-1125.
Chicago/Turabian StyleXiaowei Zhou; Yun Zhang; Wenjie Yu; Maoyuan Li; Yuhong Chen; Huamin Zhou. 2020. "An imaging performance analysis method correlated with geometrical deviation for the injection molded high-precision aspheric negative plastic lens." Journal of Manufacturing Processes 58, no. : 1115-1125.
Electrochemical inhomogeneity of lithium-ion batteries stemming from heterogeneous electrode microstructure adversely affects battery rate-performance, lifetime and safety. It is attributed to manufacturing errors of electrodes in previous studies. However, the significant heterogeneous electrochemistry is still found in commercial battery electrodes with high manufacturing accuracy. Here, we propose a conjoined-electrode structure to improve the electrochemical homogeneity, in which every two adjacent cathodes or anodes are connected through microholes on current collectors. The commercial level pouch lithium-ion battery with the conjoined-electrode structure is fabricated and it displays a better rate capability (26% higher capacity at 3C rate) and a lower capacity degradation rate (decreased by 50% in the cycling tests at 1C rate). A 3-D electrochemical-thermal model is used in simulation with inhomogeneous situations to reveal the self-balancing effects of state of charge, current density, and Li-ion concentration in the conjoined-electrode structure, which facilitate more homogeneous electrochemistry in lithium-ion batteries. The limitation factor of the self-balancing effects varies depending on the structural parameters, which limits the conjoined-electrode structure design.
Ruoyu Xiong; Tengfang Zhang; Tianlun Huang; Maoyuan Li; Yun Zhang; Huamin Zhou. Improvement of electrochemical homogeneity for lithium-ion batteries enabled by a conjoined-electrode structure. Applied Energy 2020, 270, 115109 .
AMA StyleRuoyu Xiong, Tengfang Zhang, Tianlun Huang, Maoyuan Li, Yun Zhang, Huamin Zhou. Improvement of electrochemical homogeneity for lithium-ion batteries enabled by a conjoined-electrode structure. Applied Energy. 2020; 270 ():115109.
Chicago/Turabian StyleRuoyu Xiong; Tengfang Zhang; Tianlun Huang; Maoyuan Li; Yun Zhang; Huamin Zhou. 2020. "Improvement of electrochemical homogeneity for lithium-ion batteries enabled by a conjoined-electrode structure." Applied Energy 270, no. : 115109.
In this paper, the thermal behavior and process optimization for polyamide 6 during the selective laser sintering process were systematically investigated via numerical simulations and experimental testing. The effects of laser power and scanning speed were studied, and the simulation results showed that the increasing laser power and decreasing scanning speed led to the increase of the maximum temperature and the three-dimensional size of molten pool. Then, the single-layer experiments under different process parameters were carried out to verify the accuracy of the model. In addition, the energy density was applied to evaluate the combined effect of laser power and scanning speed on the thermal behavior. A process map for parameter optimization was obtained based on the predicted results, and the optimized parameters were in the region that the powder can be remelt resulting in an enough depth of molten pool, while the maximum temperature was below the decomposition temperature. Meanwhile, the specimen selected in the remelting region showed the highest tensile strength.
Maoyuan Li; Yuchen Han; Mengyuan Zhou; Peng Chen; Huang Gao; Yun Zhang; Huamin Zhou. Experimental investigating and numerical simulations of the thermal behavior and process optimization for selective laser sintering of PA6. Journal of Manufacturing Processes 2020, 56, 271 -279.
AMA StyleMaoyuan Li, Yuchen Han, Mengyuan Zhou, Peng Chen, Huang Gao, Yun Zhang, Huamin Zhou. Experimental investigating and numerical simulations of the thermal behavior and process optimization for selective laser sintering of PA6. Journal of Manufacturing Processes. 2020; 56 ():271-279.
Chicago/Turabian StyleMaoyuan Li; Yuchen Han; Mengyuan Zhou; Peng Chen; Huang Gao; Yun Zhang; Huamin Zhou. 2020. "Experimental investigating and numerical simulations of the thermal behavior and process optimization for selective laser sintering of PA6." Journal of Manufacturing Processes 56, no. : 271-279.
Polymer orientation is a fundamental and key issue, exhibiting crucial impacts on physical properties of polymeric parts. Current methods are limited in transparent materials and fail to measure the dynamic orientation in industrial polymer processing in situ. Herein, we reported an innovative strategy that dynamic orientation for polymer molecular chains was successfully characterized in situ by dielectric method. A key dielectric-orientation theoretical model was established, and a facile interdigital electrode capacitor (IDEC) array sensor was designed. The experimental results not only agreed well with the classic elastic dumbbell model and the traditional optical measurement method, but also showed a universal applicability for different polymer solutions and a good application prospect in injection molding process. Investigated results showed that the orientation difference of 1 wt% PVDF/DMF, 1 wt% PVC/DMF and 1 wt% PS/DMF solution was 0.57, 0.97 and 0.75 at shear rate 0–407 1/s, respectively. Additionally, the method was successfully applied in injection molding (Δε, 0.25–0.88 under shear rate 56.6–250 1/s). Our strategy built a new ‘decoding fingerprint’ to the dynamic orientation of polymer.
Guancheng Shen; Yi Zhang; Yunming Wang; Wenjie Yu; Zhigao Huang; Maoyuan Li; Yun Zhang; Huamin Zhou. In situ dielectric characterization of dynamic orientation for polymer molecular chains. Sensors and Actuators B: Chemical 2020, 313, 128024 .
AMA StyleGuancheng Shen, Yi Zhang, Yunming Wang, Wenjie Yu, Zhigao Huang, Maoyuan Li, Yun Zhang, Huamin Zhou. In situ dielectric characterization of dynamic orientation for polymer molecular chains. Sensors and Actuators B: Chemical. 2020; 313 ():128024.
Chicago/Turabian StyleGuancheng Shen; Yi Zhang; Yunming Wang; Wenjie Yu; Zhigao Huang; Maoyuan Li; Yun Zhang; Huamin Zhou. 2020. "In situ dielectric characterization of dynamic orientation for polymer molecular chains." Sensors and Actuators B: Chemical 313, no. : 128024.
Due to its superior mechanical properties, graphene (Gr) has the potential to achieve high performance polymer-based nanocomposites. Previous studies have proved that defects in the Gr sheets could greatly reduce the mechanical properties of Gr, while the Stone-Wales (SW) defect was found to enhance the interfacial mechanical strength between Gr and epoxy. However, the combined effects of defects on the overall mechanical properties of Gr/epoxy nanocomposites have not been well understood. In this paper, the effect of the SW defect on the mechanical properties of Gr/epoxy nanocomposites was systematically investigated by using molecular dynamic simulations. The simulation results showed that the SW defect would degrade the mechanical properties of nanocomposites, including the Young’s modulus and in-plane shear modulus. Surprisingly, the transverse shear modulus could be remarkably enhanced with the existence of SW. The reinforcing mechanisms were mainly due to two aspects: (1) the SW defect could increase the surface roughness of the Gr, preventing the slippage between Gr and epoxy during the transverse shea; and (2) the nanocomposite with defective Gr enables a higher interaction energy than that with perfect graphene. Additionally, the effects of temperature, the dispersion and volume fraction of Gr were also investigated.
Maoyuan Li; Peng Chen; Bing Zheng; Tianzhengxiong Deng; Yun Zhang; Yonggui Liao; Huamin Zhou. Effect of Stone-Wales Defect on Mechanical Properties of Gr/epoxy Nanocomposites. Polymers 2019, 11, 1116 .
AMA StyleMaoyuan Li, Peng Chen, Bing Zheng, Tianzhengxiong Deng, Yun Zhang, Yonggui Liao, Huamin Zhou. Effect of Stone-Wales Defect on Mechanical Properties of Gr/epoxy Nanocomposites. Polymers. 2019; 11 (7):1116.
Chicago/Turabian StyleMaoyuan Li; Peng Chen; Bing Zheng; Tianzhengxiong Deng; Yun Zhang; Yonggui Liao; Huamin Zhou. 2019. "Effect of Stone-Wales Defect on Mechanical Properties of Gr/epoxy Nanocomposites." Polymers 11, no. 7: 1116.
In this study, the formability of woven carbon-fiber (CF)-reinforced polyether-ether-ketone (PEEK) composite sheets in the solid-state thermoforming process were investigated, and the failure mechanisms were discussed. The formability of the woven CF/PEEK sheets were analyzed using flexural tests, Erichsen test, and microscopic observation. The results show that the formability of CF/PEEK sheets significantly increases as the temperature rises from 165 to 325 °C, and slightly decreases as the deformation speed rises from 2 to 120 mm/min. The deformation of the sheets is caused by plastic deformation, shear deformation and squeeze deformation, without plastic thinning and fiber slippage, which is due to the restriction of the solid matrix and locked fibers. Moreover, the wrinkles will cause fiber fracture at lower temperatures and delamination at higher temperatures. At higher temperatures, the wrinkles mainly occur at the position with [0°/90°] fibers due to the squeezing of the matrix and fibers.
Bing Zheng; Xiping Gao; Maoyuan Li; Tianzhengxiong Deng; Zhigao Huang; Huamin Zhou; Dequn Li. Formability and Failure Mechanisms of Woven CF/PEEK Composite Sheet in Solid-State Thermoforming. Polymers 2019, 11, 966 .
AMA StyleBing Zheng, Xiping Gao, Maoyuan Li, Tianzhengxiong Deng, Zhigao Huang, Huamin Zhou, Dequn Li. Formability and Failure Mechanisms of Woven CF/PEEK Composite Sheet in Solid-State Thermoforming. Polymers. 2019; 11 (6):966.
Chicago/Turabian StyleBing Zheng; Xiping Gao; Maoyuan Li; Tianzhengxiong Deng; Zhigao Huang; Huamin Zhou; Dequn Li. 2019. "Formability and Failure Mechanisms of Woven CF/PEEK Composite Sheet in Solid-State Thermoforming." Polymers 11, no. 6: 966.
In this study, the mechanical and thermal properties of graphene were systematically investigated using molecular dynamic simulations. The effects of temperature, strain rate and defect on the mechanical properties, including Young’s modulus, fracture strength and fracture strain, were studied. The results indicate that the Young’s modulus, fracture strength and fracture strain of graphene decreased with the increase of temperature, while the fracture strength of graphene along the zigzag direction was more sensitive to the strain rate than that along armchair direction by calculating the strain rate sensitive index. The mechanical properties were significantly reduced with the existence of defect, which was due to more cracks and local stress concentration points. Besides, the thermal conductivity of graphene followed a power law of λ~L0.28, and decreased monotonously with the increase of defect concentration. Compared with the pristine graphene, the thermal conductivity of defective graphene showed a low temperature-dependent behavior since the phonon scattering caused by defect dominated the thermal properties. In addition, the corresponding underlying mechanisms were analyzed by the stress distribution, fracture structure during the deformation and phonon vibration power spectrum.
Maoyuan Li; Tianzhengxiong Deng; Bing Zheng; Yun Zhang; Yonggui Liao; Huamin Zhou. Effect of Defects on the Mechanical and Thermal Properties of Graphene. Nanomaterials 2019, 9, 347 .
AMA StyleMaoyuan Li, Tianzhengxiong Deng, Bing Zheng, Yun Zhang, Yonggui Liao, Huamin Zhou. Effect of Defects on the Mechanical and Thermal Properties of Graphene. Nanomaterials. 2019; 9 (3):347.
Chicago/Turabian StyleMaoyuan Li; Tianzhengxiong Deng; Bing Zheng; Yun Zhang; Yonggui Liao; Huamin Zhou. 2019. "Effect of Defects on the Mechanical and Thermal Properties of Graphene." Nanomaterials 9, no. 3: 347.
In this study, the flexural behavior and fracture mechanisms of short carbon fiber reinforced polyether-ether-ketone (SCFR/PEEK) composites at various ambient temperatures were investigated. First, the crystallinity and glass transition temperature (Tg) of PEEK and SCFR/PEEK were analyzed by differential scanning calorimetry analysis and dynamic mechanical analysis tests, respectively. The addition of SCFs increases the Tg but does not change the crystallinity of the PEEK matrix. Then, the three-point flexural tests of PEEK and SCFR/PEEK were performed over the temperature range of 20 to 235 °C, and the temperature-dependencies of the flexural properties of PEEK and SCFR/PEEK were discussed in detail. Finally, the microstructure of SCFR/PEEK was observed using a digital microscope and scanning electron microscope. The results show that the tension crack occurs first, and the crack extends upward leading to the shear crack and compression crack at room temperature. The fracture of SCFR/PEEK is mainly due to the extraction and rupture of SCFs. At high temperatures (above Tg), the tension crack and compression crack both occur, and the strong ductility of the matrix prevents the generation of shear crack. The fracture of SCFR/PEEK is mainly due to the rotation and extraction of SCFs, while the SCFs rupture plays a minor role.
Bing Zheng; Tianzhengxiong Deng; Maoyuan Li; Zhigao Huang; Huamin Zhou; Dequn Li. Flexural Behavior and Fracture Mechanisms of Short Carbon Fiber Reinforced Polyether-Ether-Ketone Composites at Various Ambient Temperatures. Polymers 2018, 11, 18 .
AMA StyleBing Zheng, Tianzhengxiong Deng, Maoyuan Li, Zhigao Huang, Huamin Zhou, Dequn Li. Flexural Behavior and Fracture Mechanisms of Short Carbon Fiber Reinforced Polyether-Ether-Ketone Composites at Various Ambient Temperatures. Polymers. 2018; 11 (1):18.
Chicago/Turabian StyleBing Zheng; Tianzhengxiong Deng; Maoyuan Li; Zhigao Huang; Huamin Zhou; Dequn Li. 2018. "Flexural Behavior and Fracture Mechanisms of Short Carbon Fiber Reinforced Polyether-Ether-Ketone Composites at Various Ambient Temperatures." Polymers 11, no. 1: 18.
Owing to its extraordinary physical properties and potential for next generation nanoelectronics, the in-plane graphene/hexagonal boron nitride (Gr/h-BN) heterostructure has been fabricated recently and gained a lot of attention. The defects located at the interface such as vacancies, topological defects are inevitable during the growth process. However, the effects of the defects on the interfacial thermal conductance between the Gr/h-BN interface have not well understood. In this work, the effects of defects on the interfacial thermal conductance across the Gr/h-BN interface have been systematically investigated by using nonequilibrium molecular dynamic simulations. The different types of single-vacancy and Stone–Wales defects were considered. The simulation results showed that the interfacial thermal conductance would decrease linearly with the increase of single-vacancy concentrations and it decreased with the existence of Stone–Wales defects, then reached a platform as concentration increased, the value of which was close to the interfacial thermal conductance of Gr/h-BN with the line defect formed by Stone–Wales defects. The analyses on the phonon vibration power spectra and the stress analysis indicated that the degradation in the in-plane modes accounted for the decrease caused by single-vacancy, while the stress concentration distribution and the ripple appeared near the interface dominated the degradation caused by Stone–Wales defects. Additionally, the effects of system dimensions and temperature on the interfacial thermal conductance were investigated.
Maoyuan Li; Bing Zheng; Ke Duan; Yun Zhang; Zhigao Huang; Huamin Zhou. Effect of Defects on the Thermal Transport across the Graphene/Hexagonal Boron Nitride Interface. The Journal of Physical Chemistry C 2018, 122, 14945 -14953.
AMA StyleMaoyuan Li, Bing Zheng, Ke Duan, Yun Zhang, Zhigao Huang, Huamin Zhou. Effect of Defects on the Thermal Transport across the Graphene/Hexagonal Boron Nitride Interface. The Journal of Physical Chemistry C. 2018; 122 (26):14945-14953.
Chicago/Turabian StyleMaoyuan Li; Bing Zheng; Ke Duan; Yun Zhang; Zhigao Huang; Huamin Zhou. 2018. "Effect of Defects on the Thermal Transport across the Graphene/Hexagonal Boron Nitride Interface." The Journal of Physical Chemistry C 122, no. 26: 14945-14953.
The effects of the dimensions, temperature, strain rate and the presence of a vacancy on the mechanical properties of γ-GNTs were systematically investigated using MD simulations.
Maoyuan Li; Yingming Zhang; Yunliang Jiang; Yun Zhang; Yunming Wang; Huamin Zhou. Mechanical properties of γ-graphyne nanotubes. RSC Advances 2018, 8, 15659 -15666.
AMA StyleMaoyuan Li, Yingming Zhang, Yunliang Jiang, Yun Zhang, Yunming Wang, Huamin Zhou. Mechanical properties of γ-graphyne nanotubes. RSC Advances. 2018; 8 (28):15659-15666.
Chicago/Turabian StyleMaoyuan Li; Yingming Zhang; Yunliang Jiang; Yun Zhang; Yunming Wang; Huamin Zhou. 2018. "Mechanical properties of γ-graphyne nanotubes." RSC Advances 8, no. 28: 15659-15666.
The effects of defects on the interfacial mechanical properties of graphene/epoxy are systematically investigated by molecular dynamic simulations.
Maoyuan Li; Helezi Zhou; Yun Zhang; Yonggui Liao; Huamin Zhou. The effect of defects on the interfacial mechanical properties of graphene/epoxy composites. RSC Advances 2017, 7, 46101 -46108.
AMA StyleMaoyuan Li, Helezi Zhou, Yun Zhang, Yonggui Liao, Huamin Zhou. The effect of defects on the interfacial mechanical properties of graphene/epoxy composites. RSC Advances. 2017; 7 (73):46101-46108.
Chicago/Turabian StyleMaoyuan Li; Helezi Zhou; Yun Zhang; Yonggui Liao; Huamin Zhou. 2017. "The effect of defects on the interfacial mechanical properties of graphene/epoxy composites." RSC Advances 7, no. 73: 46101-46108.