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Hi All, Simulations and experimental results show the wide range of values for Young’s modulus (0.5 to 5.5 TPa) and wall thickness (0.066 to 0.34 nm) of carbon nanotubes (CNTs) in literature. Most of the published results say that the set of values (Young’s modulus and wall thickness of CNT) are 1 TPa  and 0.34 nm, and the product is around 0.34 TPa-nm. In my point of view this set of values may be appropriate for multi-walled carbon nanotubes. Can we use the same set of values for analysis of single-walled carbon nanotubes (SWCNTs)?  The interlayer distance between the graphene layers is 0.34 nm. Can we use this value as wall thickness of SWCNT or do we need to use atomic thickness instead of 0.34 nm?

Dear Colleagues:

You are cordially invited to submit an abstract to the symposium on "Nanostructured Materials including Nanocrystalline Materials, Nanoporous Materials, Active Nanomaterials and Structures." This mini symposium is listed under Track 21 -- Processing and Engineering Applications of Novel Materials as (21-2 Symposium on Multifunctional Materials and Structures) at the 2007 ASME IMECE, which will be held on Nov. 12-15, 2007 in Seattle, Washington.

Hi everyone. My name is Michael Mahoney and I'm currently enrolled in the fracture mechanics course at the University of Nebraska. I am pursuing my master's degree in engineering mechanics. My advisor is Dr. Joseph A. Turner and my research is in acoustoelastic methods for characterizing stress in a material. Here is a link to our research group:  http://em-jaturner.unl.edu/.

Dear Colleague,

We are pleased to announce that the ICCES08( International Conference on
Computational and Experimental Engineering & Sciences) will be held at the
Waikiki Beach Marriott Resort & Spa, in Honolulu, Hawaii, during 17-22 March
2008.

Deadlines:
. 1 Oct 2007: Deadline for Mini-symposia proposals (email: icces [at] icces.org (icces[at]icces[dot]org)).
. 1 Oct 2007: Start abstract submission (http://www.icces.org).
. 15 Dec 2007: Deadline for abstract submission.
. 20 Dec 2007: End of abstract selection.
. 1 Jan 2008: Start early registration & hotel reservation (at discounted
rates).
. 15 Jan 2008: Deadline for early registration.
. 1 Feb 2008: Deadline for final 6-page paper submission to:
http://submission.techscience.com/icces08.
. 1 Feb 2008: Technical program announcement.
. 1 Mar 2008: Deadline for the regular registration.

The conference hotel is in a tourist area of the Waikiki Beach in Honolulu.
For those that make reservations by 1 January 2008, the hotel offers a
substantially discounted rate of about US$149/night (single or double
occupancy) (The room rates in Honolulu are normally about $265/night in
Waikiki). The conference deadlines above have been chosen to facilitate
inexpensive hotel accommodations for ALL the participants at the conference
hotel. Further details of ICCES08 will be posted continually at
http://www.icces.org. To ensure that you receive further e-mails about
ICCES08, please "sign up" at http://www.icces.org

If you are interested in hosting a mini-symposium at ICCES08, please send
us an email (icces [at] icces.org):
. The title of the Symposium,
. A brief description of the Symposium
. A list of potential participants whom you plan to invite( as comprehensive
as possible)

Each presentation at ICCES08 will be of  20 minutes duration (including
discussions). Keynote and Plenary Lectures will be of longer duration.

At ICCES08, very strict procedures will be implemented, to prevent no-shows.
Please submit an abstract, only if you intend to present the paper in
person, in good faith.

All accepted papers will appear in the open access journal, ICCES(
www.techscience.com/icces).

We look forward to welcoming you to Honolulu, Hawaii, in March 2008.

ICCES08 Organizing Committee
Email: icces [at] icces.org (icces[at]icces[dot]org)
http://www.icces.org

I am currently enrolled at University of Nebraska-Lincoln. The main courses I've taken in Solid Mechanics are Continuum Mechanics and Advanced Finite Element Method (currently taking). My undergraduate and Master major is Civil Engineering, both obtained in my home country Brazil. I would say that my strength related to this course is my motivation to understand the complex physical process of cracking, and my weakness is probably the fact that I don't have a good background in Fracture Mechanics. I am curretly pursuing my PhD at UNL under supervision of Dr. David Allen. Unfortunately our group doesn't have a published website. I am currently working on the development of a multi-scale computational model for predicting the evolution of damage in composites subject to impact loading. So, a better understanding of fracture mechanics and of the physical process underlying cracking will be of major importance to my research work. Finally, as fracture mechanics is present in any engineering application, I am sure it will greatly improve my education in a general basis.

• Various cracks in thin films under tensile or compressive stresses
• Micrographs of cracks in thin films
• A micrograph of a channel crack
• The origin of stress in a film
• Stress in a thin film due to mismatch in the coefficients of thermal expansion
• Stress in film due to bending
• Measure redisual stress using wafer curvature
• Channel crack:  initiation vs. steady propagation
• Steady-state energy release rate of a channel crack
• Channel crack in patterned structure

Calculating stresses in MD simulations is a controversial topic. There are two different schools of thought about the equivalence of the virial stress to the continuum Cauchy stress; for and against. Some argue based on momentum balance, that only the potential contribution to the virial stress should be considered as the continuum Cauchy stress. However, others assert that the total virial stress that contains both the kinetic and potential parts is indeed the quantity that corresponds to the Cauchy stress in continuum mechanics. We used a simple thermo-elastic analysis to verify the validity of using the total virial stress as the continuum Cauchy stress and found that the total virial stress is indeed the continuum Cauchy stress.