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961.
Dalla Palma Mauro Cavazzana Roberto Erculiani Andrea Gambetta Giulio Peruzzo Simone 《Journal of Thermal Analysis and Calorimetry》2020,141(5):2061-2079
Journal of Thermal Analysis and Calorimetry - The laminar two-dimensional mixed convection in a trapezoidal enclosure with a rotating inner circular cylinder and a sinusoidal bottom wall is studied... 相似文献
962.
Luís Martins Pedro Amaro Sofia Pessanha Mauro Guerra Jorge Machado Maria Luisa Carvalho José Paulo Santos 《X射线光谱测定》2020,49(1):192-199
Zinc K-shell radiative and radiationless transition rates are calculated using the multiconfiguration Dirac–Fock method. Correlation up to the 4p orbital is included in almost all transition rate calculations. Calculated radiative transition rates and transition probabilities are compared with Scofield's Dirac–Hartree–Slater and Dirac–Hartree–Fock calculations, presenting good agreement with the later. Radiative transition intensity ratios involving the strongest lines are compared with theoretical, experimental, and empirical-fit values. Most ratios are in close agreement with the empirical-fit values from NIST's Fundamental Parameters database. Calculated radiationless transition rates and ratios are compared with Chen et al.'s Dirac–Fock values and Safronova et al.'s Dirac–Fock values. The K-LL transition rates are overall lower than Chen et al.'s values, whereas the K-LX and K-XY transition rates are overall higher. Calculated K-LX/K-LL and K-XY/K-LL ratios are relatively close to the experimental values compared. Some calculated intensities relative to K-L are in good agreement with the experimental values, whereas others present worse agreement. The calculated fluorescence yield is higher than all theoretical, experimental, and empirical-fitted values compared, probably because the total radiationless transition rate value calculated in the present work is relatively low. 相似文献
963.
A computational simulation with DFT calculations and microkinetic modeling is carried out on a complete catalytic cycle, involving Staudinger ligation, aza-Wittig condensation and phosphine oxide recycle, for non-truncated substrates and catalyst. The Staudinger reaction produces phosphazenes (R3P?=?NR), also known as iminophosphoranes, from phosphines and organic azides. Electrophilic carbonyl groups react with phospazenes to produce imines and phosphine oxides. Recently the Staudinger reaction and the aza-Wittig condensation have been combined to spawn intramolecular tandems producing cyclic molecules of great pharmaceutical interest (e.g. benzoxazoles). The release of diatomic nitrogen combined with the formation of phosphine oxide represents the driving force of the reaction. The implementation of in situ recycling of the exhausted phosphine oxide into the Staudinger/aza-Wittig tandem improves the scopes and the applicability of the reaction, transforming it into a powerful and versatile synthetic tool. 相似文献
964.
In the contact of a cone with a rough plane the mean pressure in the contact area is constant. In particular, above a critical ratio of the opening angle of the cone with respect to the rms gradient of surface roughness, the mean pressure is the same of that for nominally flat contact, no matter how large is the normal load. We introduce a new variable, namely, the local density of contact area, whose integral over the smooth nominal contact domain gives the real contact area. The results given by the theoretical model agree with the numerical simulations of the same problem presented in the paper. 相似文献
965.
Journal of Optimization Theory and Applications - The detection of optimal trajectories with multiple coast arcs represents a significant and challenging problem of practical relevance in space... 相似文献
966.
Cloud computing is an emerging technology that allows to access computing resources on a pay-per-use basis. The main challenges in this area are the efficient performance management and the energy costs minimization. 相似文献
967.
The medium range order (MRO) in containerless-processed Zr-noble metal eutectic liquids has been measured using the Beamline Electrostatic Levitation (BESL) technique. High energy X-ray diffraction data were obtained for equilibrium and supercooled Zr75.5Pd24.5 and Zr80Pt20; Zr77Rh23 and Zr82Ir18; and Zr81Au19 liquids. When Zr is alloyed with 5d transition metals (Ir, Pt, Au) a prominent pre-peak in the X-ray static structure factor appears, indicating the presence of extended order. However, the position of the pre-peak is not consistent with size considerations alone. Given the similarities between the 4d and 5d alloying elements in atomic size and enthalpy of mixing with Zr, extended MRO likely exists in all of the compositions studied. 相似文献
968.
Temperature-modulated differential scanning calorimetry (TMDSC) is based on conventional DSC but with a sinusoidally modulated temperature path. Simulations of TMDSC signals were performed for Corning EAGLE XG glass over a wide range of modulation frequencies. Our results reveal that the frequency correction commonly used in the interpretation of TMDSC signals leads to a master nonreversing heat flow curve independent of modulation frequency, provided that sufficiently high frequencies are employed in the TMDSC measurement. A master reversing heat flow curve can also be generated through the frequency correction. The resulting glass transition temperature from the frequency corrected reversing heat flow is thereby shown to be independent of frequency. 相似文献
969.
Dr. Joana T. Coutinho Dr. Mauro Perfetti Dr. José J. Baldoví Dr. Maria A. Antunes Philipp P. Hallmen Heiko Bamberger Dr. Iris Crassee Dr. Milan Orlita Prof. Manuel Almeida Prof. Joris van Slageren Dr. Laura C. J. Pereira 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(7):1758-1766
Early actinide ions have large spin-orbit couplings and crystal field interactions, leading to large anisotropies. The success in using actinides as single-molecule magnets has so far been modest, underlining the need for rational strategies. Indeed, the electronic structure of actinide single-molecule magnets and its relation to their magnetic properties remains largely unexplored. A uranium(III) single-molecule magnet, [UIII{SiMe2NPh}3-tacn)(OPPh3)] (tacn=1,4,7-triazacyclononane), has been investigated by means of a combination of magnetic, spectroscopic and theoretical methods to elucidate the origin of its static and dynamic magnetic properties. 相似文献
970.
Mauro Anselmino 《Few-Body Systems》2016,57(6):373-378
The transverse momentum dependent partonic distributions and fragmentation functions should reveal new properties of the three-dimensional structure of nucleons and of the quark hadronization process. Many experimental data are now available and much progress has been made in their phenomenological interpretation. A short summary of the situation is presented. 相似文献