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Wei Hong's picture

Surface interactions between two like-charged polyelectrolyte gels

Due to the migration of mobile molecules and ions, a thin diffusive layer of distributed charge - the electric double layer - forms at the interface between a polyelectrolyte gel and a liquid ionic solution.  When two polyelectrolyte gels are brought closely together, the electric double layers overlap and interact with each other, resulting in an effective repulsion.  The multiphysics coupling nature of soft gels makes their surface interactions significantly different from the interactions between rigid solids.

Wei Hong's picture

Electric-field-induced antiferroelectric to ferroelectric phase transition in a mechanically confined perovskite oxide

The electric-field-induced phase transition was investigated under mechanical confinements in bulk samples of an antiferroelectric perovskite oxide at room temperature. Profound impacts of mechanical confinements on the phase transition are observed due to the interplay of ferroelasticity and the volume expansion at the transition. The uniaxial compressive prestress delays while the radial compressive prestress suppresses it. The difference is rationalized with a phenomenological model of the phase transition accounting for the mechanical confinement.

point contact in ball bearing

i m doing a project on ball bearing. there is a point contact between the ball and the races. when the force is applied on the inner race, the point contact turnes into elliptical surface to surface. please guide me how to model this problem in ansys.

Two PhD Candidate Positions in Advanced Superalloys Research

Two PhD candidate positions are available in the Department of Mechanical engineering at the University of Rhode Island.  These fully supported positions are for thesis research to be performed in the area of microstructure/damage interactions in advanced superalloys at elevated temperature in both air and vacuum environment.  The successful candidate must have a Master degree in areas related to numerical simulation of material behavior using Abaqus platform, has exposure to mechanical testing and is strong in both materials science and mechanics.  Interested candidates can

Murthy N. Guddati's picture

Tenure Track Faculty Position at North Carolina State University

The Department of Civil Engineering at NCSU has an opening for tenure track faculty position in the general areas of Structural Engineering and/or Mechanics. The plan is to hire the best candidate irrespective of the specific area of research focus. Interested applicants are urged to act quickly, as the final review of applications may begin as early as next week (the week of January 11). The official advertisement is given below.


element eroding VS fracture mechanics

Hi everyone,

    I am not a student majoring in the mechanics. But I have found that: the element eroding method is so powerful in numerical simulation (i.e. using ls-dyna) if we reduce the mesh size, then we can get a very perfect fracture process of material. So why we need fracutre mechanics?

solat.noruzi's picture

friction reducton

Is it possible to reduce sliding friction coefficient less in metal contact less than 0.02 ?

what is the best coating for steel surface to reduce friction ?

td's picture

Trends in Computational Nanomechanics-Transcending Length and Time Scales

I am happy to announce the forthcoming volume titled Trends in Computational Nanomechanics - Transcending Length and Time Scales 

Amit Acharya's picture

Traveling Wave solutions for a quasilinear model of Field Dislocation Mechanics

(in Journal of the Mechanics and Physics of Solids)

Johannes Zimmer, Karsten Matthies, Amit Acharya

Jianliang Xiao's picture

van der Waals interaction controls orientations of single-walled carbon nanotubes on quartz during growth

Single-walled carbon nanotubes (SWNTs) possess extraordinary electrical and mechanical properties, with many possible applications in electronics and materials science. Dense, horizonally aligned arrays of linearly configured SWNTs represent perhaps the most attractive and scalable way to implement this class of nanomaterial in practical systems. Recent work shows that templated growth of tubes on certain crystalline substrates (e.g. quartz) yields arrays with the necessary levels of perfection, as demonstrated by the formation of devices and full systems on quartz.

Material modlelling


Any body working on microstructural modelling, here i want know how to construct Basic real microstructure to FE mesh ?? 

Melosh Competition: 2nd Call for Abstracts and Travel Fellowships

This is the second call for abstracts for the 22nd Annual Melosh Competition for the Best Student Paper on Finite Element Analysis.  Extended abstracts are due by January 8, 2010.   Details of the competition and submission procedure can be found here

BoJing Zhu's picture

Can we use constitutive relation at micro/macro scale to molecules scale ?

Hi, everyone


Now I meet a problem, wish can obtain you help.


Now i do some research on multi-compose particle materials (eg. pharmaceutical science  materials)___predict the compressibility, compactibility, flow properties and  breakage behavior.

as we know, the molecular scale at 0.1-70nm scale and crystal growth process at 0.1-100nm scale, can i use the constitutive relationship at micro(=~um)/macro to analyze the performance and structure at this scale.


thanks ! 

Amit Pandey's picture

2009 Nathan M. Newmark Medal

C. S. Desai Is Recipient of the 2009 Nathan M. Newmark Medal

C S Desai

Regents’ Professor Chandra Desai has been awarded the 2009 Nathan M.
Newmark Medal by the Structural Engineering and Engineering Mechanics
Institutes of the American Society of Civil Engineers.



Hi all,

 I´m traying to simulate a low-cycle fatigue crack growth in Abaqus 6.9 using xfem. My problem is to add the low cycle method to the xfem solution. 

I believe that the only current option for this would be to manually
create the loading curve and to do the analysis by a brute force
method but i may not be correct in this assumption however.

Please could someone explain a brief method.

i appreciate in advance.



Buryachenko's picture

Welcome to new background of micromechanics

Dear Colleagues,

 I am please to let you know about the birth of a new background of micromechanics defining a new field of micromechanics called computational analytical micromechanics (CAM). It offers opportunities for a fundamental jump in multiscale research (see the abstract attached, where avalable electronic publications are indicated and encouraged for reading). However, these opportunities can be realized only in the case of joint efforts of both computational micromechanic's society and the analyticalone. I would be happy if CAM piques your attention.

GOPALAERO2000's picture

Residual stress measurement

Hi Everyone,

 I would like to measure the residual stress imposed pattern through thickness of the plate by forming process (bending). Is it possible?

 I came to know that residual stress measurement through HOLE DRILLING METHOD offers only on the surface. That too, applicable only when residual stress imposed is uniform through thickness (like shot blasting process). If any one came across the experience of residual stress measurement, please throw some light in this regard.

 Thanks in advance

 M Gopalakrishnan

Post Doctoral Research Associate in the area of high strain rate loading and multiscale modeling at RPI

There is an immediate opening for a postdoctoral research position in the Advanced Computational Research Laboratory at RPI, Troy NY to work on problems involving high strain rate loading conditions and multiscale modeling. Encouraged to apply are creative, self-motivated candidates with a sound background in computational mechanics. RPI is home to the CCNI, one of the most powerful university-based super-computational research facilities in the world.

rajnish0007's picture

How to simulate pull out test in ABAQUS ??

Choose a channel featured in the header of iMechanica: 

hello all

How to simulate pull out test in ABAQUS 6.9  ???

How to deal with negetive plastic strain increment in FEA in an elasto - plastic problem

In case of elasto-plastic problem it is mentioned that unloading of an integration point should be started along the elastic moduli when the solution gives a negetive increment of the plastic strain at the integration point. If anyone could elaborate it a little more, it will be really helpful.


asit_rathod1's picture

Stress Defination

Hello All//

I am always confuing on that Stress is a point Function..and not Seen Physically Than Stress is a material Property or Material Behaviour?

Waiting For Answer..


Wendtland (1972) experimental results on natural frequencies of cracked cantilever beams

The effects of edge cracks on the natural frequencies of cracked cantilever beams have been extensively studied by Wendtland (1972). These results are referred to by quite a number of related journal papers; the refernce is:

Wendtland D. A¨ nderung der biegeegenfrequenzen einer idealisierten Schaufel durch Risse. Ph.D. Dissertation, University of Karlsruhe; 1972.

Does anyone know how this can be accessed online, or atleast the complete set of results for eigenfrequency (first three modes of vibration) changes due to edge cracks at different positions and depths?


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