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541.
Andrej B. Arbuzov Renat R. Sadykov Zbigniew Wa̧s 《The European Physical Journal C - Particles and Fields》2013,73(11):1-18
Isolated lepton momenta, in particular their directions are the most precisely measured quantities in pp collisions at LHC. This offers opportunities for multitude of precision measurements. It is of practical importance to verify if precision measurements with leptons in the final state require all theoretical effects evaluated simultaneously or if QED bremsstrahlung in the final state can be separated without unwanted precision loss. Results for final-state bremsstrahlung in the decays of narrow resonances are obtained from the Feynman rules of QED in an unambiguous way and can be controlled with a very high precision. Also for resonances of non-negligible width, if calculations are appropriately performed, such separation from the remaining electroweak effects can be expected. Our paper is devoted to validation that final-state QED bremsstrahlung can indeed be separated from the rest of QCD and electroweak effects, in the production and decay of Z and W bosons, and to estimation of the resulting systematic error. The quantitative discussion is based on Monte Carlo programs PHOTOS and SANC, as well as on KKMC which is used for benchmark results. We show that for a large class of W and Z boson observables as used at LHC, the theoretical error on photonic bremsstrahlung is 0.1 or 0.2 %, depending on the program options used. An overall theoretical error on the QED final-state radiation, i.e. taking into account missing corrections due to pair emission and interference with initial state radiation is estimated respectively at 0.2 % or 0.3 % again depending on the program option used. 相似文献
542.
Jaroslav Galba Juraj Pieanský Andrej Kov
Dominika Oleov Ondrej Cehlr Martin Kertys Petr Kozlík Petra Chaov Barbora Tir
ov Kristin Slí Peter Miku 《Molecules (Basel, Switzerland)》2021,26(2)
Oxandrolone, a synthetic testosterone analog, is used for the treatment of several diseases associated with weight loss. Unfortunately, oxandrolone is abused by many athletes and bodybuilders due to its strong anabolic effect. We have developed and validated a highly sensitive and rapid on-line SPE-UHPLC-MS/MS method for the determination of oxandrolone and simultaneous identification of its major metabolite 17-epi-oxandrolone in urine matrices. Enrichment of the analytes via an integrated solid-phase extraction was achieved using an Acquity UPLC BEH C18 Column. Subsequently, the chromatographic separation of the on-line preconcentrated sample fraction was achieved using an Acquity HSS T3 C18 Column. For the structural identification of these analytes, a high-resolution mass spectrometer Synapt-G2Si coupled to the Acquity M-class nano-LC system with ionKey source was used. A highly sensitive determination of oxandrolone was achieved using a tandem quadrupole mass spectrometer XEVO TQD. The method was successfully validated in the linear range of oxandrolone from 81.63 pg·mL−1 (limit of quantification, LOQ) to 5000 pg·mL−1 in the human urine matrix. It was applied to the analysis of real urine samples obtained from a healthy volunteer after the oral administration of one dose (10 mg) of oxandrolone. Concentration vs. time dependence was tested in the time interval of 4 h–12 days (after oral administration) to demonstrate the ability of the method to detect the renal elimination of oxandrolone from the human body. Favorable performance parameters along with successful application indicate the usefulness of the proposed method for its routine use in antidoping control labs. 相似文献
543.
Dr. Kristína Plevová Dr. Péter Kisszékelyi Dr. Denisa Vargová Samuel Andrejčák Viktor Tóth Lukáš Fertáľ Dr. Erik Rakovský Dr. Juraj Filo Prof. Dr. Radovan Šebesta 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(62):15501-15507
Diastereoselective double C−H heteroarylation of chiral ferrocenes provides valuable compounds with multiple functionalities using mild reaction conditions and simple reagents. Pd-Complexes with chiral mono-protected amino acids afforded corresponding heteroarylated ferrocenyl amines in good yields and high diastereomeric purities. In this way, a variety of indole, thiophene, pyrrole, or furan substituents were introduced to the ferrocene moiety. Furthermore, a range of relevant functional groups, for example ketone, ester, chloro, nitro, or silyl, are tolerated by this method. An alternative combination of amino acid and ferrocenyl amine configurations was leveraged to provide the complementary diastereomeric products. The products of C−H heteroarylation can be transformed into corresponding phosphines. Absolute configurations of CH-activation products were confirmed by the combination of X-ray crystallographic analysis and CD spectroscopy. 19F NMR kinetic study and DFT calculations provided insights into the reaction mechanism and reasons governing stereoinduction. 相似文献
544.
Reiffová Katarína Podolonovičová Jana Oriňák Andrej Flórián Karol Gondová Tat’ána 《平面色谱法杂志一现代薄层色谱法》2003,16(1):52-57
JPC – Journal of Planar Chromatography – Modern TLC - A rapid, simple qualitative thin-layer chromatographic method has been developed for separation of mono- and fructooligosaccharides... 相似文献
545.
Ulrike Grossner Jens S. Christensen Bengt G. Svensson Andrej Yu. Kuznetsov 《Superlattices and Microstructures》2005,38(4-6):364
Single-crystal ZnO has been hydrothermally grown with additional In2O3 in the solution. Schottky barrier contacts have been deposited by electron beam evaporation of Pd onto the face. Capacitance–voltage measurements have been performed to reveal the carrier concentration as a function of the In2O3 content in the solution, and secondary-ion mass spectrometry was used to measure the resulting In concentration in the samples. For an In2O3 content of 2×1019 cm−3, the average free electron concentration increased to 5×1018 cm−3 compared to 4×1017 cm−3 for the non-doped material. An increase of the In2O3 content to 4×1019 cm−3 leads to a measured carrier concentration of approximately 1×1019 cm−3; however, only up to a quarter of the incorporated In became electrically active. From thermal admittance spectroscopy measurements two prominent electronic levels are found, and compared with to the non-doped material case, the freeze-out of the shallow doping in the In-doped samples takes place at lower temperatures (below 80 K). 相似文献
546.
Andrej Zlatoš 《Journal of Functional Analysis》2004,207(1):216-252
We construct non-random bounded discrete half-line Schrödinger operators which have purely singular continuous spectral measures with fractional Hausdorff dimension (in some interval of energies). To do this we use suitable sparse potentials. Our results also apply to whole line operators, as well as to certain random operators. In the latter case we prove and compute an exact dimension of the spectral measures. 相似文献
547.
The correlation between recent PAS results and the outcomes from mechanical testing of RPV model alloys are presented, here significant changes due to different chemical composition and different irradiation levels are observed. The influence of alloying elements to the microstructure degradation process following irradiation was identified by analysis of the mean-lifetime parameter, since an interesting interdependency of this parameter with hardness was observed. 相似文献
548.
A. A. Ogloblin S. A. Goncharov Yu. A. Glukhov A. S. Dem’yanova M. V. Rozhkov V. P. Rudakov W. H. Trzaska 《Physics of Atomic Nuclei》2003,66(8):1478-1488
A review of recent experiments on the study of the nuclear rainbow phenomenon in scattering and some reactions induced by light heavy ions is given. It includes (i) the study of the differential cross sections of the 16O + 12C elastic scattering at seven 16O energies between 130 and 281 MeV; (ii) finding of the phenomenological potential deeper than that of folding model; (iii) the first data on 16O + 14C elastic scattering; (iv) dispersion relation analysis of the obtained data and observation of abnormal nuclear dispersion; and (v) use of the charge-exchange 14C(6Li,6He)14N reaction to search for pion-condensation effects. 相似文献
549.
Results of radionuclide activity concentration measurements in deposition and ground-level air conducted at the station of
the Institute of Physics situated 3.5 km from the Ignalina Nuclear Power Plant (Ignalina NPP) in 2005 are analyzed. Atmospheric
depositional fluxes of 7Be, 60Co and 137Cs are estimated. Radionuclide particle deposition rates are calculated. The Hybrid Single-Particle Lagrangian Integrated
Trajectory (HYSPLIT) model of the global dispersion and deposition is used to explain variations in the 137Cs activity concentration in the ground-level air in the Ignalina NPP region in 2005. An increase in the 137Cs activity concentration of up to 17.4 μBq m−3 on 30 October-5 November is studied. Modelling results show that the Chernobyl NPP Unit 4 Sarcophagus and the radiocaesium
resuspension from the Chernobyl NPP accident polluted regions are sources of 137Cs to the environment of the Ignalina NPP. Results on solubility in water of aerosols — carriers of 137Cs — are discussed. 相似文献
550.
Vladimír Slugeň Andrej Zeman Martin Petriska Vladimir Kršjak 《Applied Surface Science》2006,252(9):3309-3315
Positron annihilation spectroscopy (PAS) lifetime study was applied in the evaluation of the microstructure parameters and degradation processes of nuclear reactor pressure vessel (RPV) steel surveillance specimens. Study was oriented to the material investigation of Russian WWER-1000 steels (15Kh2MNFAA and 12Kh2N2MAA) with higher Ni content (1.26 wt.% in base metal and 1.7 wt.% in weld). For comparison, the WWER-440 weld metal (Sv10KhMFT) without Ni was measured too. Specimens were studied in as received stage, after irradiation in LVR-15 experimental reactor to the neutron fluence F(E > 0.5 MeV) = 4 × 1023 m−2 s−1 and after annealing in vacuum at 475 °C/2 h. Post-irradiation thermal treatment and annealing of defects was well detected by different PAS techniques. It was observed that the sensitivity of PAS parameters to defined irradiation treatment decreases with Ni-content increase. Results confirm the hypothesis that Ni affects size (decrease) and distribution (more homogeneous) of the Cu- and P-rich clusters and MxCx carbides. 相似文献