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Palladium and cerium oxide nanoparticles obtained by pulsed laser ablation (PLA) in liquid (water or ethanol) have been used as nanostructured precursors for synthesis of the composite Pd/CeO2 catalysts. The initial mixture of Pd and CeO2 nanoparticles does not show catalytic activity at temperatures lower than 100°C. It has been found that the composites prepared by PLA in alcohol are easily activated by calcination in air at 450-600°C demonstrating high activity at room temperature. Application of XRD, TEM and XPS reveals that laser ablation in water leads to the formation of large and well crystallized nanoparticles of palladium and CeO2, whereas ablation in alcohol results in formation of much smaller PdCx nanoparticles. The activation of the composites takes place due to the strong Pd-ceria interaction which occurs easier for highly-dispersed defective particles obtained in alcohol. Such interaction implies the introduction of palladium ions into the ceria lattice with formation of a mixed phase of PdxCe1-xO2-x-δ solid solution at the contact spaces of palladium and cerium oxide nanoparticles. The TPR-CO and XPS data show clearly that on the surface of the PdxCe1-xO2-x-δ solid solution the oxidized PdOx(s)/Pd-O-Ce(s) clusters are formed. These clusters comprise the highly reactive oxygen which is responsible for the high catalytic activity in LTO CO.Please do not adjust margins Please do not adjust margins CO (molecules/cm 3 ), X is the CO conversion, V RM is the reaction mixture rate (cm 3 /sec), m is the weight of the sample (g), and

Here, we report on ZnO nanoparticles (NPs) generated by nanosecond pulsed laser (Nd:YAG, 1064 nm) through ablation of metallic Zn target in water and air and their comparative analysis as potential nanomaterials for biomedical applications. The prepared nanomaterials were carefully characterized in terms of their structure, composition, morphology and defects. It was found that in addition to the main wurtzite ZnO phase, which is conventionally prepared and reported by others, the sample laser generated in air also contained some amount of monoclinic zinc hydroxynitrate. Both nanomaterials were then used to modify model wound dressings based on biodegradable poly l-lactic acid. The as-prepared model dressings were tested as biomedical materials with bactericidal properties towards S. aureus and E. coli strains. The advantages of the NPs prepared in air over their counterparts generated in water found in this work are discussed.

In this review, we introduce the current state of the art of the growth technology of pure, lightly doped, and heavily doped (solid solution) nonlinear gallium selenide (GaSe) crystals that are able to generate broadband emission from the near infrared (IR) (0.8 mm) through the mid-and far-IR (terahertz (THz)) ranges and further into the millimeter wave (5.64 mm) range. For the first time, we show that appropriate doping is an efficient method controlling a range of the physical properties of GaSe crystals that are responsible for frequency conversion efficiency and exploitation parameters. After appropriate doping, uniform crystals grown by a modified technology with heat field rotation possess up to 3 times lower absorption coefficient in the main transparency window and THz range. Moreover, doping provides the following benefits: raises by up to 5 times the optical damage threshold; almost eliminates two-photon absorption; allows for dispersion control in the THz range independent of the mid-IR dispersion; and enables crystal processing in arbitrary directions due to the strengthened lattice. Finally, doped GaSe demonstrated better usefulness for processing compared with GaSe grown by the conventional technology and up to 15 times higher frequency conversion efficiency. INTRODUCTIONThe e-polytype of gallium selenide (hereinafter GaSe) has been known since 1934 1 and promises efficient optical frequency conversion and detection over a large range of wavelengths. The performance potential of GaSe, which belongs to the point group symmetry 6m2, can be attributed to its extreme physical properties. GaSe has a broadband transparency window over the range of 0.62-20 mm for non-polarized light continues at wavelengths o50 mm 2,3 . Other attractive physical properties of GaSe are its prodigious birefringence B 5 0.375 at l 5 10.6 mm and 0.79 at terahertz (THz) range 4 , and very high second-order nonlinear susceptibility d 22 5 54 pm V 21 at 10 mm 5 and 24.3 pm/V in the THz band 6 . Among the mid-infrared (IR) anisotropic nonlinear crystals, GaSe has the second highest optical damage threshold 7,8 and thermal conductivity in the plane of the (0001) A GaSe crystal was first used for laser frequency conversion in the mid-IR in 1972 9,10 . In subsequent years, GaSe was widely used for inlab mid-IR applications 5 . Over the past two decades, GaSe has been among the most promising nonlinear optical crystals for efficient generation of ultrabroadband radiation 0.8-5640 mm (with the

Pt−CeO 2 nanocomposites were obtained by coprecipitation, varying the Pt loading over a wide range of 1−30 wt %. The samples were calcined in air at 450−1000 °C. The Pt−CeO 2 nanocomposites were investigated by a set of structural (X-ray diffraction, extended X-ray absorption fine structure (EXAFS), pair distribution function (PDF), and transmission electron microscopy) and spectroscopic (X-ray photoelectron spectroscopy and Raman spectroscopy) methods. Over the whole range of Pt loading, the main species were Pt 2+ and Pt 4+ . They were localized either in a single-atom state or in the form of PtO x clusters on the ceria surface. The joint PDF and EXAFS modeling based on the combination of [Pt 2+ O 4 ] single-atom and Pt 3 O 4 structural fragments allowed us to propose the local structure of the PtO x clusters. The formation of such surface structures is associated with a distorted ceria surface on the Pt−CeO 2 nanocomposites. We assume that the close arrangement of platinum ions in the PtO x clusters could be responsible for the effective redox properties of the samples.