Navigation Links
Nature of bonding determines thermal conductivity
Date:5/3/2011

nce, who is also currently a visiting professor at the University of Lige. "Phase change materials are very well suited because they are poor conductors of heat not only in the unordered but also in the ordered state, in contrast to semiconductors, for example," adds Prof. Matthias Wuttig from RWTH Aachen University. As part of an international research team, Hermann and Wuttig are investigating the reasons for this surprising material behaviour on alloys of germanium, antimony and tellurium. With the aid of sophisticated scattering experiments at the European Synchrotron Radiation Facility (ESRF) in Grenoble, they demonstrated that the bonding conditions between the atoms in the crystalline state as well as deviations from the perfect lattice structure influence the transmission of these vibrations through the material and thus reduce its thermal conductivity.

"The starting point for our investigations was the observation by our Japanese colleagues that the amorphous material is harder than the crystalline," says Hermann. "This contradicted all assumptions, but the measured stronger bonding forces between the atoms in the amorphous state fitted the picture." The Jlich scientists investigated how the atoms in the specimens vibrate both locally in the atomic range and also over longer distances. "In the crystalline material, we found harder vibrations for the long-range order and better conductivity for sound than in amorphous material. This is normal and is related to an increase in the order. However, we were surprised by the results for short-range vibrations in the crystal. They were softer. The short-range order in crystalline material is therefore lower than in amorphous material. This is very unusual."

On the basis of all the experimental results, the Aachen research group headed by Wuttig developed a model to explain the apparent contradictions. "Normally, the propagation of sound waves in material correlates with the thermal conductivit
'/>"/>

Contact: Angela Wenzik
a.wenzik@fz-juelich.de
49-246-161-6048
Helmholtz Association of German Research Centres
Source:Eurekalert

Page: 1 2 3

Related biology technology :

1. DOE JGI Director Eddy Rubin highlights the genomics of plant-based biofuels in the journal Nature
2. Natures Premium(R) Brand First Fresh Pork in North America to Carry DNA TraceBack(R) Seal of Authenticity
3. James L. Wittliff, Ph.D., FACB, to Present Predicting Breast Cancer Outcome with Gene Expression Signatures on the Ziplex(R) System at the Association for Molecular Pathology Conference, October 30
4. Genetic clock makers at UC San Diego publish their timepiece in Nature
5. MySignatureBook Certified Compliant With SAFE-BioPharma Digital Standard(TM)
6. Webcast Alert: Regulus Therapeutics, Alnylam Pharmaceuticals and Isis Pharmaceuticals Announce New Nature Publication on miR-21 Conference Call
7. Nature Medicine study shows Peregrines bavituximab can cure lethal virus infections
8. Research Published in Nature Medicine Shows Disruption of Chemokine Interactions Inhibits Atherosclerosis in Mice
9. Data Published in Nature Cell Biology Reveal Novel Function of Drug Target EpCAM in Cancer Cell Signalling
10. Light-speed nanotech: Controlling the nature of graphene
11. Nature Reviews Publishes Article About Jennerexs Multi-Mechanistic Cancer Therapeutic
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/29/2015)... New Columbia, Pa. (PRWEB) May 29, 2015 ... approached Thermal Product Solutions with a request to ... uniformly remove excess moisture from prescription medications being ... a custom solution that includes a robotic gantry, ... precisely positions and dries trays of 3D-printed pills ...
(Date:5/29/2015)... RESEARCH TRIANGLE PARK, N.C. , May 29, 2015 ... today that Roger Jeffs , Ph.D., President and Co-Chief ... update on the company,s business at the Jefferies 2015 Global ... The presentation and the immediately following Q&A session ... AM Eastern Time, and can be accessed via a live ...
(Date:5/28/2015)... , May 28, 2015 ... has announced the addition of Jain PharmaBiotech,s ... Markets and Companies"  to their offering.  ... disease remains a challenge in management. With ... in the seven major markets of the ...
(Date:5/28/2015)... May 27, 2015 Research and ... of Jain PharmaBiotech,s new report "Nanobiotechnology ... offering. An increasing use of ... is anticipated. Nanotechnology will be applied at ... formulations for optimal delivery to diagnostic applications ...
Breaking Biology Technology:New industrial oven with “pill pushing” robotic gantry precisely removes excess moisture from 3D-printed pharmaceuticals 2Global Alzheimer Disease Report 2015-2024 - New Drugs, Markets and Companies 2Global Alzheimer Disease Report 2015-2024 - New Drugs, Markets and Companies 3Global Nanobiotechnology Market 2015-2024 - Applications, Markets and Companies 2Global Nanobiotechnology Market 2015-2024 - Applications, Markets and Companies 3
... , ... Web Service Available Immediately to Researchers Worldwide,Free/Full NGS-based Runs Available to First Registrants ... Westborough, MA (PRWEB) ... and easy-to-use ChIP-Seq workflow solution available immediately as a web cloud service ...
... Corporation, a spinal and orthopaedic implant and instrument company ... the launch of four new product offerings. The ... Valeo(®) C VBR, Valeo(®) Concise Cervical Plating System and ... American Spine Society (NASS) prepares to meet in San ...
... Nov. 10 Genoptix, Inc. (Nasdaq: GXDX ), a ... the Lazard Capital Management 6th Annual Healthcare Conference at The ... 2009. , Genoptix,s EVP and CFO, Doug Schuling, ... beginning at approximately 11:25 a.m. EST. He will provide ...
Cached Biology Technology:GenomeQuest Places ChIP-Seq Workflow Solution On SDM “Cloud” 2GenomeQuest Places ChIP-Seq Workflow Solution On SDM “Cloud” 3GenomeQuest Places ChIP-Seq Workflow Solution On SDM “Cloud” 4Amedica Announces New Product Offering 2Genoptix Announces Participation at Lazard Capital Management 6th Annual Healthcare Conference 2
(Date:4/27/2015)... more than four decades, AUVSI,s Unmanned Systems ... event for the unmanned land, sea, and air industries. ... local, national, or trade news organization interested in gathering ... applications of unmanned technologies. The conference will explore the ... and how it will soon impact the lives of ...
(Date:4/20/2015)... April 20, 2015 The announcement ... Glenbeigh Records Management (GRM), Ireland,s ... Islamic Bank. Having built up an impressive track record of ... leading player within the records management sector in ... double is GCC staffbase and employ a further eight staff ...
(Date:4/13/2015)... 2015  higi, a leading cloud-based consumer engagement platform ... engage with their communities around health and wellness, announced ... secure API.  ... affordable, and convenient vehicle to receive validated health information ... The API will allow higi,s trusted partners, on ...
Breaking Biology News(10 mins):UNMANNED SYSTEMS 2015: Largest International Conference and Trade Show for the Drone and Unmanned Technology Industry 2UNMANNED SYSTEMS 2015: Largest International Conference and Trade Show for the Drone and Unmanned Technology Industry 3UNMANNED SYSTEMS 2015: Largest International Conference and Trade Show for the Drone and Unmanned Technology Industry 4UNMANNED SYSTEMS 2015: Largest International Conference and Trade Show for the Drone and Unmanned Technology Industry 5Glenbeigh Records Management Wins Contract With Dubai Islamic Bank 2Glenbeigh Records Management Wins Contract With Dubai Islamic Bank 3higi Launches Seamless Access to HIPAA-Compliant Health Outcomes and Activity Data 2higi Launches Seamless Access to HIPAA-Compliant Health Outcomes and Activity Data 3
... say "shade grown, please" when you order your morning ... under a canopy of multiple tree species, not only ... also maintain genetic diversity of native tree species and ... The finding comes from a study published by ...
... bone marrow that can continuously make red and white ... Michigan lab. This development could lead to ... defects and a continuous supply of blood for transfusions. ... mimics the tissues supporting bone marrow in the body, ...
... Dec. 22, 2008 NYU Langone Medical Center scientists and ... Calif., have discovered an unexpected cause for the fatal seizures ... central nervous system, according to a study published in the ... of thinking about how the human immune system responds to ...
Cached Biology News:Shade coffee benefits more than birds 2Shade coffee benefits more than birds 3Biomedical researchers create artificial human bone marrow in a test tube 2Peering inside the skull of a mouse to solve meningitis mystery 2Peering inside the skull of a mouse to solve meningitis mystery 3
...
The Holten mini vertical flow workbench provides a particle-free environment for sample protection against airborne contaminants....
...
... Shakers combine high durability and capacity ... of use. The patented triple-counterbalanced heavy-duty ... to run at high speed with ... temperature range is delivered with tight ...
Biology Products: