# research

## Nanoscience and Technology

Synthesis, Characterization and Phase Transitions

## Journal Club Theme of July 2007: Mechanics of Hydrogels

Before we start this issue of J-club, I would like to recommend Prof. Langer's lecture for his MRS Von Hippel Award in the 2005 MRS Fall Meeting (Langer, 2006). His lecture not only delineated the history of the new exciting field of drug delivery and controlled release, but also told us many interesting stories happened in his career development. With Prof. Langer's pioneer work, many new materials are developed for designing new drug delivery and controlled drug release systems.

## List of Journals in Microfluidics

I am working in the area of microfuidics and wish to apply meshless methods to solve electroosmotic flow in microchannel. Can anybody suggest the journals which accepts papers on this field.

Key Words: Microfluidics, Navier-Stokes equations, microchannels, electroosmotic flow

## Maths in the study of fractured surfaces

Hello,

I'm working now at a study about the possibles applications of mathematics in fracture mechanics.Please give me the suggestions about the possibles Mathematics applied in the Fracture Mechanics:

(- fuzzy;

-hypermathematics

-fractal geometry).

Thank you very much.

## Nonlinear finite elements

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How to use the hybrid/mixed method to solve geometrical nonlinear problems?
It seems the the difficulties are how to choos strss(Cauchy, Lagrange or Kirchhoff ) and the corresponding expression of energy functional. When the large deformation is considered, the equilibrium equation is coupled with the displacements and the complementary energy is different with linear problems.

## Cohesive interface line element

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Dear  researchers,

I'm working with line cohesive interface element. It is been implemented  in Fortran Code. I have some doubts about it.

The first one is: this element will be coupled with shell element, but as the line interface element doesn't have degrees of freedom of rotation this could cause some problems. Someone knows a formulation to line interface element that incorporate rotation in formulation?

## Lath martensite

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Does any one knows a good reference about lath martensite?

Why we see the retained austenite? why doesn't it transformto martensite? What's its effect on the phase transformation? Does the plasticity change the morphology of the transfromation? How about the speed of the transfromation? When should we expect to see the lath martensite? What's the effect of the diagonal terms in the transformation matrix? What's the effect of the shear components? Is there any difference between 2d and 3d simulations, and which one is more realistic?

## Austenite Martensite transformation

Does any one knows a good reference about lath martensite?

Why we see the retained austenite? why doesn't it transformto martensite? What's its effect on the phase transformation? Does the plasticity change the morphology of the transfromation? How about the speed of the transfromation? When should we expect to see the lath martensite? What's the effect of the diagonal terms in the transformation matrix? What's the effect of the shear components? Is there any difference between 2d and 3d simulations, and which one is more realistic?

## Cohesive zone modeling

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I am trying to use cohesive zone modeling for bimaterial fracture in ANSYS, but I have some problem while inputing the data. Can anybody suggest how to use cohesive zone modeling in ANSYS.

## Constant Stress across a Beam

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Hello,

## End Notched Flexure Problem

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Hi

I want to model an End Notched Flexure (ENF) specimen in ABAQUS for
studying the mode II fracture behaviour in laminated composites.

I have modeled the problem using shell elements and continuum shell
elements.

To prevent the two legs from penetration, I have examined almost all
of connector types (in ABAQUS/CAE) and also contact types but the
results have not been satisfactory.

At this moment I don't have any idea about what to do.

Can anybody help me in this regard?

Best Regards

Kamyar

## ABAQUS ( viscoelastic material model)

Does any one know how to implement other viscoelastic material models, like Burgers' model, in ABAQUS? To my knowledge only Prony series can be used to model visoelastic materials in ABAQUS/standard.

thanks,

Milliyon

Small version

## Open Source Publishing Flow Chart

Here is my flow cart...

## Non-conformability in Mesh-free Methods

Can any one please tell me where to find some mathematical proof (or justification) of the non-conformability arises due to misalignment of background cell and the support domain in mesh-free methods based on Galerkin formulation.

Amit

## Elastoplastic Indentation Stress Field

This model has a simple closed-form analytical expression, matching with finite element results nearly perfectly.

Ref: G. Feng, S. Qu, Y. Huang and W.D. Nix, An analytical expression for the stress field around an elastoplastic indentation/contact, Acta Materialia, V.55, 2007, P2929-2938. http://dx.doi.org/10.1016/j.actamat.2006.12.030

## Mimics Innovation Awards 2007 Winners Announced!

June 1st  2007, Materialise announced the winners of the Mimics Innovation Awards 2007 at the International Mimics User Group Meeting in Washington, D.C.

We congratulate:

• Category 1: Innovative implant design system & the development of innovative medical procedures.

Vos W. – University Hospital Antwerp, Belgium

## Discusssion on Crystal plasticity

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Discusssion on Crystal plasticity
(1):How to establish a model which reflect the size effect in material
(2):How to form the finite element implementation of equilibrium field equation

I hope to have discussion with you in these topics
My E-mail: zhangxu26@126.com