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We consider some trends, achievements and a series of remaining problems in the precision determination of parton distribution functions. For the description of the scaling violations of the deep-inelastic scattering data, forming the key ingredients to all PDF fits, a solid theoretical framework is of importance [...]

In perturbative calculations, e.g., in the setting of Quantum Chromodynamics (QCD) one aims at the evaluation of Feynman integrals. Here one is often faced with the problem to simplify multiple nested integrals or sums to expressions in terms of indefinite nested integrals or sums. [...]

A dielectric-loaded linac powered by THz-pulses is one of the key parts of the 'Attosecond X-ray Science: Imaging and Spectroscopy' (AXSIS) project at DESY, Hamburg. As in conventional accelerators, the AXSIS linac is designed to have phase velocity equal to the speed of light which, in this case, is realized by tuning the thickness of the dielectric layer and the radius of the vacuum channel. [...]

The fine detail in the x-ray absorption spectra in the energy region of absorption edgesprovides the insight into the mechanism of inner-shell photoexcitation: in particular in spectra offree atoms or simple molecules, the simplest being gaseous hydrides [1-2].Measured K edge absorption spectra of hydrides of 3p (PH3, H2S in HCl) and 4p (GeH4,AsH3, H2Se, HBr) elements, and published data of 2p hydrides (CH4, NH3, H2O, HF) as well asSiH4 [3-6] and the noble gases at the end of the isoelectronic series (Ne, Ar, Kr) are compared tothe respective calculated spectra, obtained by atomic HF86, GRASP codes [7] and molecularDFT (Density functional theory) ORCA code [8]. For a clearer view of intraatomic processes,the weak and simple structural (XAFS) signal of the molecule is removed from the spectra.Among the spectral features below the continuum limit, those with the lowest energybelong to the transition of the core electron to the lowermost free orbitals with the molecularcharacter. [...]

The goal of this research is to establish the working state and correlations between atomic structure and catalytic activity of nanoshaped CuO/CeO2 catalysts used in N2O decomposition reaction. The catalysts contained CuO nanoclusters dispersed over different CeO2 morphologies: nano-rods and nano-cubes. [...]

X-ray absorption spectra in the energy region of absorption edges reveal fine details of themechanism of inner-shell photoexcitation: in particular in spectra of free atoms or simplemolecules, the simplest being gaseous hydrides [1-2]. In a collection of data from consecutiveand homologous elements, analyzed by a common procedure, the reaction channels can beidentified with better precision and reliability than in analysis of individual spectra.Absorption spectra of the hydrides of 3p elements (PH3, H2S in HCl) were measured at theXAFS beamline of the Elettra synchrotron in Trieste: a new type of adjustable absorption cellfor measurement of noxious gases at room temperature and at low photon energies wasdeveloped for the purpose. [...]

Coatings based on TiO2 are extensively investigated material for the preparation of surfaces which are referred as self-cleaning. Under solar illumination these coatings catalyze pollutants degradation and enhance their removal from the surface due to photoinduced superhydrophilicity [1]. [...]

Soils derived from ultramafic or serpentine rocks are characterized by elevated concentrations of Ni, Cr and Co. About 2% of plants on ultramafic soils accumulate metals in their shoots: a phenomenon known as hyperaccumulation [...]

TiO2 is the most studied photocatalyst for environmental application. The industrial scale application of TiO2 is facing numerous problems andimmobilization of active and stable layers is among them [...]

The possibilities of the operando XAS analysis of catalysts will be presented on two casestudies of promising new catalytic materials: alkali doped nano-dispersed copper oxideclusters on ordered mesoporous SiO2, which is highly active and selective towards propyleneepoxidation [1], and nanoshaped CuO/CeO2 catalysts used in N2O decomposition reaction [2].Operando Cu K-edge and Ce L3-edge XANES and EXAFS analysis was performed duringcatalytic reactions under controlled reaction conditions in a tubular reactor filled withprotective He atmosphere at 1 bar. The spectra were measured before the reaction at RT, thenduring heating, and during catalytic reaction at 400 °C under controlled atmosphere.Operando XANES analysis is used to monitor the changes in valence states and localsymmetries of Cu and Ce cations in the catalysts. [...]