TY - JOUR
A1 - Zhao, Jun-Hua
A1 - Wang, L.
A1 - Jiang, Jin-Wu
A1 - Wang, Z.
A1 - Guo, Wanlin
A1 - Rabczuk, Timon
T1 - A comparative study of two molecular mechanics models based on harmonic potentials
JF - Journal of Applied Physics
N2 - A comparative study of two molecular mechanics models based on harmonic potentials
KW - Angewandte Mathematik
KW - Strukturmechanik
Y1 - 2013
ER -
TY - JOUR
A1 - Zhao, Jun-Hua
A1 - Jiang, Jin-Wu
A1 - Jia, Yue
A1 - Guo, Wanlin
A1 - Rabczuk, Timon
T1 - A theoretical analysis of cohesive energy between carbon nanotubes, graphene and substrates
JF - Carbon
N2 - Explicit solutions for the cohesive energy between carbon nanotubes, graphene and substrates are obtained through continuum modeling of the van der Waals interaction between them. The dependence of the cohesive energy on their size, spacing and crossing angles is analyzed. Checking against full atom molecular dynamics calculations and available experimental results shows that the continuum solution has high accuracy. The equilibrium distances between the nanotubes, graphene and substrates with minimum cohesive energy are also provided explicitly. The obtained analytical solution should be of great help for understanding the interaction between the nanostructures and substrates, and designing composites and nanoelectromechanical systems.
KW - Angewandte Mathematik
KW - Strukturmechanik
Y1 - 2014
U6 - http://dx.doi.org/10.1016/j.carbon.2013.01.041
SP - 108
EP - 119
ER -
TY - JOUR
A1 - Zhao, Jun-Hua
A1 - Guo, Wanlin
A1 - Rabczuk, Timon
T1 - An analytical molecular mechanics model for the elastic properties of crystalline polyethylene
JF - Journal of Applied Physics
N2 - We present an analytical model to relate the elastic properties of crystalline polyethylene based on a molecular mechanics approach. Along the polymer chains direction, the united-atom (UA) CH2-CH2 bond stretching, angle bending potentials are replaced with equivalent Euler-Bernoulli beams. Between any two polymer chains, the explicit formulae are derived for the van der Waals interaction represented by the linear springs of different stiffness. Then, the nine independent elastic constants are evaluated systematically using the formulae. The analytical model is finally validated by present united-atom molecular dynamics (MD) simulations and against available all-atom molecular dynamics results in the literature. The established analytical model provides an efficient route for mechanical characterization of crystalline polymers and related materials.
KW - Angewandte Mathematik
KW - Strukturmechanik
Y1 - 2012
U6 - http://dx.doi.org/10.1063/1.4745035
ER -
TY - JOUR
A1 - Zhang, Yancheng
A1 - Zhao, Jun-Hua
A1 - Jia, Yue
A1 - Mabrouki, Tarek
A1 - Gong, Yadong
A1 - Wei, Ning
A1 - Rabczuk, Timon
T1 - An analytical solution on the interface debonding for large diameter carbon nanotube-reinforced composite with functionally graded variation interphase
JF - Composite Structures
N2 - An analytical solution on the interface debonding for large diameter carbon nanotube-reinforced composite with functionally graded variation interphase
KW - Angewandte Mathematik
KW - Strukturmechanik
Y1 - 2013
SP - 261
EP - 269
ER -
TY - JOUR
A1 - Zhao, Jun-Hua
A1 - Lu, Lixin
A1 - Rabczuk, Timon
T1 - Binding energy and mechanical stability of single- and multi-walled carbon nanotube serpentines
JF - The Journal of Chemical Physics
N2 - Binding energy and mechanical stability of single- and multi-walled carbon nanotube serpentines
KW - Angewandte Mathematik
KW - Strukturmechanik
Y1 - 2014
U6 - http://dx.doi.org/10.1063/1.4878115
ER -
TY - JOUR
A1 - Zhao, Jun-Hua
A1 - Jia, Yue
A1 - Wei, Ning
A1 - Rabczuk, Timon
T1 - Binding energy and mechanical stability of two parallel and crossing carbon nanotubes
JF - Journal of Applied Mechanics
N2 - Binding energy and mechanical stability of two parallel and crossing carbon nanotubes
KW - Angewandte Mathematik
KW - Strukturmechanik
Y1 - 2015
ER -
TY - JOUR
A1 - Zhao, Jun-Hua
A1 - Lu, Lixin
A1 - Zhang, Zhiliang
A1 - Guo, Wanlin
A1 - Rabczuk, Timon
T1 - Continuum modeling of the cohesive energy for the interfaces between _lms, spheres, coats and substrates
JF - Computational Materials Science
N2 - Continuum modeling of the cohesive energy for the interfaces between _lms, spheres, coats and substrates
KW - Angewandte Mathematik
KW - Strukturmechanik
Y1 - 2015
SP - 432
EP - 438
ER -
TY - JOUR
A1 - Zhao, Jun-Hua
A1 - Wei, Ning
A1 - Fan, Z.
A1 - Jiang, Jin-Wu
A1 - Rabczuk, Timon
T1 - Mechanical properties of three types of carbon allotropes
JF - Nanotechnology
N2 - Mechanical properties of three types of carbon allotropes
KW - Angewandte Mathematik
KW - Strukturmechanik
Y1 - 2013
ER -
TY - THES
A1 - Zhao, Jun-Hua
T1 - Multiscale modeling of nanodevices based on carbon nanotubes and polymers
T1 - Multiskalige Modellierung von auf Kohlenstoffnanoröhren und Polymeren basierenden Nanobauteilen
N2 - This thesis concerns the physical and mechanical interactions on carbon nanotubes and polymers by multiscale modeling. CNTs have attracted considerable interests in view of their unique mechanical, electronic, thermal, optical and structural properties, which enable them to have many potential applications.
Carbon nanotube exists in several structure forms, from individual single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) to carbon nanotube bundles and networks. The mechanical properties of SWCNTs and MWCNTs have been extensively studied by continuum modeling and molecular dynamics (MD) simulations in the past decade since the properties could be important in the CNT-based devices. CNT bundles and networks feature outstanding mechanical performance and hierarchical structures and network topologies, which have been taken as a potential saving-energy material. In the synthesis of nanocomposites, the formation of the CNT bundles and networks is a challenge to remain in understanding how to measure and predict the properties of such large systems. Therefore, a mesoscale method such as a coarse-grained (CG) method should be developed to study the nanomechanical characterization of CNT bundles and networks formation.
In this thesis, the main contributions can be written as follows: (1) Explicit solutions for the cohesive energy between carbon nanotubes, graphene and substrates are obtained through continuum modeling of the van der Waals interaction between them. (2) The CG potentials of SWCNTs are established by a molecular mechanics model. (3) The binding energy between two parallel and crossing SWCNTs and MWCNTs is obtained by continuum modeling of the van der Waals interaction between them. Crystalline and amorphous polymers are increasingly used in modern industry as tructural materials due to its important mechanical and physical properties. For crystalline polyethylene (PE), despite its importance and the studies of available MD simulations and continuum models, the link between molecular and continuum descriptions of its mechanical properties is still not well established. For amorphous polymers, the chain length and temperature effect on their
elastic and elastic-plastic properties has been reported based on the united-atom (UA) and CG MD imulations in our previous work. However, the effect of the CL and temperature on the failure behavior is not understood well yet. Especially, the failure behavior under shear has been scarcely reported in previous work. Therefore, understanding the molecular origins of macroscopic fracture behavior such as fracture energy is a fundamental scientific challenge.
In this thesis, the main contributions can be written as follows: (1) An analytical molecular mechanics model is developed to obtain the size-dependent elastic properties of crystalline PE.
(2) We show that the two molecular mechanics models, the stick-spiral and the beam models, predict considerably different mechanical properties of materials based on energy equivalence. The difference between the two models is independent of the materials. (3) The tensile and shear failure behavior dependence on chain length and temperature in amorphous polymers are scrutinized using molecular dynamics simulations. Finally, the influence of polymer wrapped two neighbouring SWNTs’ dispersion on their load transfer is investigated by molecular dynamics (MD) simulations, in which the SWNTs' position, the polymer chain length and the temperature on the interaction force is systematically studied.
T3 - ISM-Bericht // Institut für Strukturmechanik, Bauhaus-Universität Weimar - 2014,1
KW - Mehrskalenmodell
KW - Kohlenstoff Nanoröhre
KW - Polymere
KW - Multiscale modeling
KW - Carbon nanotubes
KW - Polymers
Y1 - 2014
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20140130-21078
ER -
TY - JOUR
A1 - Zhang, Yancheng
A1 - Wei, Ning
A1 - Zhao, Jun-Hua
A1 - Gong, Yadong
A1 - Rabczuk, Timon
T1 - Quasi-analytical solution for the stable system of the multi-layer folded graphene wrinkles
JF - Journal of Applied Physics
N2 - Quasi-analytical solution for the stable system of the multi-layer folded graphene wrinkles
KW - Angewandte Mathematik
KW - Strukturmechanik
Y1 - 2013
ER -
TY - JOUR
A1 - Jiang, Jin-Wu
A1 - Zhao, Jun-Hua
A1 - Rabczuk, Timon
T1 - Size-Sensitive Young’s Modulus of Kinked Silicon Nanowires
JF - Nanotechnology
N2 - We perform both classical molecular dynamics simulations and beam model calculations to investigate the Young's modulus of kinked silicon nanowires (KSiNWs). The Young's modulus is found to be highly sensitive to the arm length of the kink and is essentially inversely proportional to the arm length. The mechanism underlying the size dependence is found to be the interplay between the kink angle potential and the arm length potential, where we obtain an analytic relationship between the Young's modulus and the arm length of the KSiNW. Our results provide insight into the application of this novel building block in nanomechanical devices.
KW - Angewandte Mathematik
KW - Strukturmechanik
Y1 - 2013
U6 - http://dx.doi.org/10.1088/0957-4484/24/18/185702
ER -
TY - JOUR
A1 - Vu-Bac, N.
A1 - Lahmer, Tom
A1 - Keitel, Holger
A1 - Zhao, Jun-Hua
A1 - Zhuang, Xiaoying
A1 - Rabczuk, Timon
T1 - Stochastic predictions of bulk properties of amorphous polyethylene based on molecular dynamics simulations
JF - Mechanics of Materials
N2 - Stochastic predictions of bulk properties of amorphous polyethylene based on molecular dynamics simulations
KW - Angewandte Mathematik
KW - Stochastik
KW - Strukturmechanik
Y1 - 2014
SP - 70
EP - 84
ER -
TY - JOUR
A1 - Jiang, Jin-Wu
A1 - Zhao, Jun-Hua
A1 - Zhou, K.
A1 - Rabczuk, Timon
T1 - Superior thermal conductivity and extremely high mechanical strength in polyethylene chains from ab initio calculation
JF - Journal of Applied Physics
N2 - The upper limit of the thermal conductivity and the mechanical strength are predicted for the polyethylene chain, by performing the ab initio calculation and applying the quantum mechanical non-equilibrium Green’s function approach. Specially, there are two main findings from our calculation: (1) the thermal conductivity can reach a high value of 310 Wm−1 K−1 in a 100 nm polyethylene chain at room temperature and the thermal conductivity increases with the length of the chain; (2) the Young’s modulus in the polyethylene chain is as high as 374.5 GPa, and the polyethylene chain can sustain 32.85%±0.05% (ultimate) strain before undergoing structural phase transition into gaseous ethylene.
KW - Angewandte Mathematik
KW - Strukturmechanik
Y1 - 2012
U6 - http://dx.doi.org/10.1063/1.4729489
ER -
TY - JOUR
A1 - Zhao, Jun-Hua
A1 - Kou, Liangzhi
A1 - Jiang, Jin-Wu
A1 - Rabczuk, Timon
T1 - Tension-induced phase transition of single-layer molybdenum disulphide (MoS2) at low temperatures
JF - Nanotechnology
N2 - Tension-induced phase transition of single-layer molybdenum disulphide (MoS2) at low temperatures
KW - Angewandte Mathematik
KW - Strukturmechanik
Y1 - 2014
U6 - http://dx.doi.org/10.1088/0957-4484/25/29/295701
ER -
TY - JOUR
A1 - Ben, S.
A1 - Zhao, Jun-Hua
A1 - Zhang, Yancheng
A1 - Rabczuk, Timon
T1 - The interface strength and debonding for composite structures: review and recent developments
JF - Composite Structures
N2 - The interface strength and debonding for composite structures: review and recent developments
KW - Angewandte Mathematik
KW - Strukturmechanik
Y1 - 2015
ER -