Search results for "surface structure"

A comparative thermogravimetric study of waterlogged archaeological and sound woods

2010

Waterlogged archaeological woods Pinus pinaster and Fagus sylvatica L. were analyzed by using TG technique. Degradation processes ascribable to the holocellulose decay were evidenced at nearly the same temperature for sound and archaeological samples. The residual matters at 600 and 900 °C of the sound woods are much lower than those of archaeological waterlogged woods in agreement with the presence of inorganic materials encapsulated during the burial into the marine environment. It was proposed a new protocol to rapidly calculate the maximum water content parameter, which is related to the wood degradation state. TG experiments at variable heating rates were performed to obtain kinetic pa…

Thermogravimetric and Sorption Measurement Techniques/Instruments

2002

The survey covers commercially offered instruments for the determination of the surface structure of porous solids based on isothermal measurement of physisorption of inert gases and of thermogravimetric instruments. Basic assumptions, features and experimental uncertainties are compared.

X-ray microtomography and laser ablation in the analysis of ink distribution in coated paper

2015

A novel method was developed for studying the ink-paper interface and the structural variations of a deposited layer of ink. Combining high-resolution x-ray tomography with laser ablation, the depth profile of ink (toner), i.e., its varying thickness, could be determined in a paper substrate. X-ray tomography was used to produce the 3D structure of paper with about 1 μm spatial resolution. Laser ablation combined with optical imaging was used to produce the 3D structure of the printed layer of ink on top of that paper with about 70 nm depth resolution. Ablation depth was calibrated with an optical profilometer. It can be concluded that a toner layer on a light-weight-coated paper substrate …

Entire Reflective Object Surface Structure Understanding

2015

International audience

An empirical method to determine the free surface energy of solids at different deformations and temperatures regimes : An application to Al.

2005

Abstract We have performed molecular dynamics (MD) simulations using the three low index surfaces of Al to determine the variation of the surface energy as a function of deformation and temperature. We have also developed an empirical formulation for the surface free energy as a function of deformation. The observed difference between the numerical and analytical results has led us to divide the deformation into a mechanical and a thermal contribution. From this observation, we have obtained an expression for the surface free energy placing the temperature dependence on the bulk and surface elastic constants. Our simulations permitted us to analyze the multilayer relaxation for the particul…

A remark on the surface structure of polyethylene single crystals

1967

Structure and properties ofn-alkyldimethylsilyl bonded silica reversed-phase packings

1978

Summary The effects of the modifier functionality and the chain length ofn-alkylchlorosilanes on the surface structure of packings and on their retention behaviour in reversed-phase chromatography were investigated. Comparative retention studies on three silica packings that had been treated to maximum conversion withn-octyltrichlorosilane (I),n-octylmethyldichlorosilane (II) andn-octyldimethylmonochlorosilane (III) showed that the most pronounced reversed-phase character is obtained by using III as the modifying reagent. A series ofn-alkyldimethylsilyl bonded silica packings were prepared with widely differingn-alkyl chain lengths. Although the packings are very hydrophobic, the maximum su…

Elucidating the ligand shell structure and dynamics of Au683MBA32 gold nanocluster using molecular dynamics simulations

2017

Synthesising novel gold nanoparticles and -clusters can be often easier than characterising them, and after experimental analysis many options for the possible molecular formula of the cluster may remain as equally valid options. These options may be investigated by quantum computational means, such as density functional theory, but since DFT includes the electronic interactions, this might take time and excessive effort if the amount of options is large. In this thesis a new way of easing the computational task is introduced by a novel method, that combines a guessing algorithm and molecular dynamics simulations. The algorithm produces possible structures by utilising existing structures o…

X-ray microtomography and laser ablation in the analysis of ink distribution in coated paper

2015

A novel method was developed for studying the ink-paper interface and the structural variations of a deposited layer of ink. Combining high-resolution x-ray tomography with laser ablation, the depth profile of ink (toner), i.e., its varying thickness, could be determined in a paper substrate. X-ray tomography was used to produce the 3D structure of paper with about 1 lm spatial resolution. Laser ablation combined with optical imaging was used to produce the 3D structure of the printed layer of ink on top of that paper with about 70 nm depth resolution. Ablation depth was calibrated with an optical profilometer. It can be concluded that a toner layer on a light-weight-coated paper substrate …