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The 1TW HELEN laser at AWE has been used to obtain data on material properties at high pressures and strain-rates. This paper presents recent results from experiments in some of these areas. These studies include measurements of the Principal shock Hugoniot from (relative) impedance match experiments using aluminium as the standard. Shock transit times are measured using optical streak cameras to record the times of shock breakout on stepped targets. Attention to target fabrication, step height measurement and streak camera calibration have enabled us to achieve an accuracy of ~1% in shock velocity. The techniques developed in this programme have applications to other experiments such as hohlraum drive characterisation. Designs for off-Hugoniot EOS experiments, including adiabatic compression, by shaping the hohlraum X-ray drive are being studied The feasibility of this has already been tested by using a shaped laser pulse to generate an increased duration steady single shock. A Michelson interferometer has been developed to assess the effects of preheat on EOS targets by measuring surface motion before shock arrival. This instrument has also been used to measure spall strengths and thicknesses in bulk aluminium at the very high strain rates associated with such laser experiments. [ABSTRACT FROM AUTHOR]

We present some recent results of a systematic study regarding polymer-based nanocomposites with carbon nanostructures as guest components. This paper is focused on the coupling of conductive polymers, as polyanilines and polythiophenes, with nanodiamond grains. The peculiar properties of such crystalline nanomaterial not only help in improving the mechanical and thermal properties of the host polymeric matrices, but also act on the polymerization mechanism, modifying the morphological features of the polymers. Triggered by the nanodiamond presence, the final nanocomposites show a prominent arrangement of polymer segments into tubular forms and a subsequent structural organization suitable for many technological applications. [ABSTRACT FROM AUTHOR]

XAFS analysis can be applied to various fields such as material science, environmental study, biological science, etc. and is widely used for characterization in those fields. In the early days that XAFS technique was started to be used, scientists wrote their own code for XAFS data analysis. As XAFS technique became very popular and XAFS community grew big, a several analysis code or package had been developed and submitted for people to use. The REX2000 is one of those XAFS analysis packages, which is commercially available. Counting up from its predecessor “REX”, REX2000 has been used for more than 15 years in XAFS society. From the previous modification in 2003, a major change was made in this year of 2006. For a dynamical study of advanced material, many XAFS DATA were measured (quick XAFS and in-situ XAFS) and hundreds of DATA sets need to be processed. The REX2000’s DATA handling is improved to cope with those huge volume DATA at once and report the fitting result as CSV file. Well-established user-interface is enhanced so that user can customize initial values for data analysis and specify the options through graphical interface. Many small changes are made and described in this paper. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Determination of ultra trace elements is important in many disciplines both in basic and applied sciences. Numerous applications show their importance in medical science, environmental science, materials science, food processing and semiconductor industries and in maintaining the quality control of ultra pure chemicals and reagents. We report commissioning of a synchrotron based total reflection x-ray fluorescence (TXRF) facility on the BL-16 microfocus beamline of Indus-2. This paper describes the performance of the BL-16 TXRF spectrometer and the detailed description of its capabilities through examples of measured results. [ABSTRACT FROM AUTHOR]

In the paper is presented energy method that determines the electric field pressure on a conductor. This method is more understandable for mechanical faculty students, which is way for them it is easier to comprehend the material. It is shown that molecular electric fields of the order of 1011 V/m create huge tension (∼1010∼Pa) and they are responsible for the strength of the solids. In this way we introduce electrical picture in determining the strength of the solid and show one of the application of physics in material science and strength of material classes. [ABSTRACT FROM AUTHOR]

In sheet forming, the creation of wrinkles in the flange area of the blank commonly occurs. When diaphragm forming aligned-fiber-reinforced thermoplastic composites, observations reveal that the wrinkles tend to occur at angles oriented at forty-five degrees to the axis of the fibers. Intuition suggests that this is related to shear, but this may be misleading. The results of a stress-analysis and buckling analysis of this flange wrinkling problem are discussed. The forming of the thermoplastic sheets occurs at elevated temperatures and the sheet is essentially inextensible in the fiber direction. This leads to high anisotropy ratios of in-plane stiffness properties. The out-of-plane bending of the sheet will be strongly influenced by the presence of polymeric diaphragms. To investigate the buckling problem for this forming situation, a finite-difference formulation was developed. The solution revealed that only when one considers the combined effect of the thermoplastic composite and the polymeric diaphragms does the analysis predict the observed forty-five degree buckles. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]