A NiMoP/Al2O3 catalyst deactivated at the industrial plant was subjected to oxidative regeneration and reactivation with water and an aqueous solution of citric acid. The catalyst was studied at all ...stages by XRD, UV–vis, Raman spectroscopy, FTIR spectroscopy, XPS and HRTEM methods. The catalyst samples after oxidative regeneration, treatment with water and rejuvenation with citric acid were tested in hydrotreatment of the model feedstock and straight-run gasoil. It was established that the regenerated catalyst contained phosphorus strongly bound to the support and soluble or insoluble Ni and Mo compounds. The catalyst after water treatment contained only insoluble Ni and Mo compounds and a phosphate monolayer, while treatment with citric acid resulted in the formation of citrate complex compounds. Ni and Mo compounds in the sulfide form, which were obtained from insoluble components, showed high activity in the target hydrotreating reactions.
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•Regeneration of NiMoP/Al2O3 catalyst deactivated in industry was studied.•Phosphorus is strongly bonded with the support after regeneration stage.•Ni and Mo present as soluble and insoluble compounds after regeneration.•Ni and Mo sulfide compounds bonded with Al2O3 via PO4- have higher activity.
We establish estimates (interior and up to the boundary) of solutions of the inequality
, where
is a linear second-order differential operator with impulse singularities. The results in particular ...apply to the Neumann boundary value problem. The relationship between this inequality and the class of concave functions of one variable is studied.
In order to simulate ITER transient events with surface heat load parameters relevant to edge-localized-mode (ELM) impacts, tungsten samples were exposed to pulsed heat loads using pure deuterium (D) ...and with 10% helium (He) seeding plasmas in quasi-stationary high-current plasma gun QSPA-T. The pulse duration was 1 ms that is relevant to ELMs and number of pulses was varied from one to thirty. The power load was 0.7 MJ/m2 that is below the tungsten melting temperature (Tm). Two tungsten samples were used, namely, polycrystalline tungsten without (W) and with pre-existing He-induced W ‘fuzz’ (Wf). Similar to the steady state plasma, the presence of He in tungsten leads to a reduction of the D retention during transient events at temperature below Tm. We explained it as interruption of the D diffusion towards to the bulk of tungsten by (i) the strain field induced by He bubbles and (ii) the formation of interconnected He bubbles at high temperature which leads to an open porosity for accelerated D desorption, thus, decreasing the D influx into the tungsten bulk. But as the He retention in Wf decreases below 1019 He/m2, the effect of He on the D retention after the plasma gun irradiation disappears: the D retention in W and Wf is the same after 30 pulses of the exposure to pure D plasma. In both cases of pure D and He seeded D plasma gun exposures, the D retention is higher compared to the steady state plasma exposure at sample temperature above 600 K.
For the solutions of the linear differential inequality
, where
is a linear differential operator of order
defined on functions of one variable, we establish estimates of the form
, where
,
,
,
is ...the Sobolev space of
times differentiable functions,
is the Lebesgue space of integrable functions, and the constant
is independent of the choice of the function
.
Properties of the approximate rotation of vector fields generated by multivalued maps of monotone type are studied. Analogs of the Hopf theorems on the extension of multivalued maps without singular ...points and homotopy classification of the corresponding vector fields are proved. Applications to variational inequalities and operator inclusions are outlines.
The stoichiometry and phase homogeneity of the kesterite type compound Cu2ZnSnS4 play a key role in its efficiency in solar cells. In this work, CuCl2, ZnCl2 and SnCl2 were applied as solvents in the ...Cu2ZnSnS4 crystal growth for the first time. The multiphase ingot was obtained by direct fusion of the stoichiometric batch composed of constituent elements. Compared to that, the material recrystallized in SnCl2 presented a single-phase Zn-rich kesterite with composition Cu1.94Zn1.06SnS4 and unit cell parameters of a = 5.4324(3) and c = 10.8383(2) Å. The crystal structure of Cu1.94Zn1.06SnS4 was determined by single crystal X-ray diffraction analysis. The integral phase purity of the crystals grown with the use of the SnCl2 solvent was verified by powder X-ray diffraction analysis and Raman measurements. In the Raman spectrum, the FWHM value of the 337 cm−1 line was as low as 9.6 cm−1 that indicates the minimal lattice disorder.
This article provides a review of the phenomenon of entopy or local atopy from the viewpoint of allergic phenotypes and endotypes. A clinical form of the entopy endotype is local allergic rhinitis, ...which is still a fertile area for research. The exact mechanisms in the breakdown of allergen tolerance in entopy remain unclear. The review focuses on the pathogenesis, diagnostic algorithm, and the choice of treatment strategies in local allergic rhinitis.
A promising approach to study condensed-matter systems is to simulate them on an engineered quantum platform
. However, the accuracy needed to outperform classical methods has not been achieved so ...far. Here, using 18 superconducting qubits, we provide an experimental blueprint for an accurate condensed-matter simulator and demonstrate how to investigate fundamental electronic properties. We benchmark the underlying method by reconstructing the single-particle band structure of a one-dimensional wire. We demonstrate nearly complete mitigation of decoherence and readout errors, and measure the energy eigenvalues of this wire with an error of approximately 0.01 rad, whereas typical energy scales are of the order of 1 rad. Insight into the fidelity of this algorithm is gained by highlighting the robust properties of a Fourier transform, including the ability to resolve eigenenergies with a statistical uncertainty of 10
rad. We also synthesize magnetic flux and disordered local potentials, which are two key tenets of a condensed-matter system. When sweeping the magnetic flux we observe avoided level crossings in the spectrum, providing a detailed fingerprint of the spatial distribution of local disorder. By combining these methods we reconstruct electronic properties of the eigenstates, observing persistent currents and a strong suppression of conductance with added disorder. Our work describes an accurate method for quantum simulation
and paves the way to study new quantum materials with superconducting qubits.
In the present work, helium (He) was incorporated into tungsten (W) samples by inductively coupled plasma (ICP) source above the threshold of He-induced W ‘fuzz’ formation on W surface. Then, W ...samples with and without nano-structured W ‘fuzz’ were exposed to pulsed heat loads using deuterium (D) plasma in quasi-stationary high-current plasma gun QSPA-T. The pulse duration was 1 ms and number of pulses was varied from one to thirty to simulate ITER transient events with surface heat load parameters relevant to edge-localized-mode (ELM) impacts. The irradiation was performed below and above the W melting threshold. The D and He retention in each irradiated sample was measured by a method of thermal desorption spectroscopy. We examined the impact of (i) ELMs-like events and (ii) formation of He-induced nano-structured ‘fuzz’ on the D retention in W. We found that the D retention was the highest for samples irradiated by plasma gun above the melting threshold after thirty pulses. Moreover, the D retention after 10 pulses of deuterium plasma gun exposure was higher than that after stationary low-energy plasma exposure at sample temperature of either 600 or 700 K indicating the dominate influence of ELM's-like events on the D retention compared to normal operation regime. The D retention in W samples with the presence of He-induced W ‘fuzz’ was slightly smaller than without that after one pulse of plasma gun exposure with heat load below the W melting temperature. The W ‘fuzz’ was not disappear in this loading conditions, only the length and thickness of nano-structured W fibres were reduced by factors of ∼4 and ∼2, respectively. The He concentration in W with W ‘fuzz’ was decreased by a factor of about 3 after one pulse of plasma gun exposure. The results obtained give possibility to assess the particle retention in divertor areas subjected to high thermal loads at different operation regimes.
The influence of parasitic parameters (resistance and inductance) in the power grid on the diagnostic precision for resistance spot welding is considered. The effectiveness of various control ...algorithms with fluctuations in grid voltage is assessed. A method is proposed for determining the grid’s parasitic parameters.
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