Articles you may be interested inThe structure of N2 adsorbed on the rumpled NaCl(100) surface-A combined LEED and DFT-D study J. Chem. Phys. 137, 174705 (2012); 10.1063/1.4764299The monolayer structure of CO 2 adsorbed on the NaCl(100) single crystal surface: A tensor low-energy electron diffraction analysis A two-dimensional quantum crystal: H 2 on NaCl (100) Experimental and theoretical studies of the monolayer structure of OCS adsorbed on NaCl(001): Coexistence of orientationally inequivalent phases Monolayers of pure ortho-H 2 , para-H 2 , para-D 2 and normal-H 2 adsorbed on NaCl͑001͒ single crystal surfaces were investigated at temperatures Tу10 K and pressures between 1ϫ10 Ϫ10 and 1ϫ10 Ϫ5 mbar by polarization Fourier transform infrared attenuated total internal reflection spectroscopy ͑PIRS-ATR͒. Single induced polarized infrared absorptions of the fundamental vibrational modes of pure (M ϭ͉1͉) ortho-H 2 and para-H 2 , as well as pure (M ϭ͉1͉) para-D 2 and, slightly shifted, in the mixture of normal-H 2 were observed, allowing definite assignments of each. With respect to the gas phase values, the wave numbers were measured to be redshifted by 32.0 and 28.0 cm Ϫ1 for pure (M ϭ͉1͉) ortho-H 2 and para-H 2 . In close agreement with potential calculations, these absorptions were assigned to H 2 molecules adsorbed on the cation sites of the large NaCl͑001͒ terraces, while neither the absorptions associated with H 2 adsorption above defects nor the absorptions of (M ϭ0) H 2 molecules above the anion sites, detected on microcrystallite surfaces at lower temperature, are observed under the conditions set. The present experiments corroborate the fact that the NaCl surface discriminates between the (M ϭ͉1͉) ortho-, (M ϭ0) ortho-and paraspecies. The lateral interactions have no influence on the stable sites and the discrimination, but they contribute by an additional shift of the peak frequencies of about 15%. Moreover, with polarized light, induced transition dipole moments perpendicular to the surface for ortho-H 2 , para-H 2 and para-D 2 were observed, while none parallel to the surface was detected. These results are in accordance with the calculations showing that the s-component of the polarization disappears due to free rotation of the H 2 (D 2 ) molecules in a plane parallel to the surface, while the p-component gives a maximum intensity. The integrated cross sections Ќ were measured and found to have the same order of magnitude: (6Ϯ3)ϫ10 Ϫ22 m/molecule for (M ϭ͉1͉) ortho-H 2 and (4Ϯ2)ϫ10 Ϫ22 m/molecule for para-H 2 within the error limits; the theoretical value is 4.5ϫ10 Ϫ22 m/molecule for both species. Applying the extended Langmuir equation, the difference between the desorption energies (E des ortho ϪE des para ) of (Mϭ͉1͉) ortho-H 2 and para-H 2 adsorbed on the ͑001͒ terraces of NaCl͑film͒ was determined to be 0.6Ϯ0.2 kJ/mol, in agreement with the calculated value ͑0.8 kJ/mol͒. Assuming that the sticking coefficients of (M ϭ͉1͉) ortho-H 2 and para-H 2 are not dependent on temperature between 17 and 30 K,...

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On the basic of literature data on ablation was characterized as a method of nanoparticles preparation. The own research concerned the direct ultrafast laser ablation of solids used to produce the engineering nanoparticles with narrow size distributions. Without using any chemical precursors, stoichiometric nanoparticles are generated from different materials (silver, gold, NiTi alloy) and directly dispersed in a liquid, e.g. acrylic acid, acetone, water, or a monomer of polymeric material. The produced nanoparticle solutions may be used to fabricate nano-modified plastic materials with specially designed properties by polymerization directly subsequent to particles' production, without the necessity to re-disperse the particle aggregates. In order to control the size distribution and related properties, nanomaterial characterization using on-line measurements of the particle size is applied. The developed processes give access to new homogeneous nanomaterials such as multi-component nanosystems.

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Due to their outstanding properties, interest in lasers has increased greatly in precision agriculture as a potential tool for non‐chemical weed control. unwanted plants have a negative effect on crop growth, especially in close surroundings. Weed control based on mechanical (e.g. hoeing) or thermal (flaming) methods do not meet the precision requirements to preserve crop plants. An innovative combination of image processing and laser technology is promising.

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