—
Adhesion/decohesion processes on the surface of dense metallic diffusion membranes in direct contact with hydrogen have been studied by scanning electron microscopy and energy dispersive X-ray ...spectroscopy. The elemental composition of the alloys has been determined to be (wt %) Pd
93
Y
7
, Pd
100 –
х
Pb
х
(
х
= 5, 20), and Pd
94
Ru
6
. We have revealed Pb emission from the surface of the Pd
100 –
х
Pb
х
membranes and Pb adhesion to the surface of the Pd
93
Y
7
membranes. No adhesion of yttrium particles to the surface of the palladium–lead membranes has been detected. The surface of Pd
94
Ru
6
alloy has good stability to adhesion/decohesion processes.
We point out that the diphoton excess at about 750 GeV recently discovered by the LHC experiments can be explained within supersymmetric models with low scale supersymmetry breaking with sgoldstino ...as a natural candidate. We discuss phenomenological consequences of this scenario describing possible signatures to test this hypothesis.
—
We have studied the effect of surface lamp processing on the hydrogen permeability of membrane foil produced by rolling an ingot of a Pd–Cu solid solution. Such processing has been shown to remove ...sorption products from the membrane surface and to significantly improve the hydrogen permeability of the membranes at temperatures of up to 300°C. The use of a reactor with a cleaned PdCu membrane allows the hydrogen yield in the methanol steam reforming process in the presence of a Ni
0.2
Cu
0.8
/Ce
0.3
Zr
0.7
O
2–δ
catalyst to be raised relative to that in a conventional flow reactor owing to the displacement of thermodynamic equilibrium as a result of the removal of hydrogen from the reaction zone. The effect of membrane surface cleaning by lamp processing is most clearly demonstrated by examining the yield of high-purity hydrogen in the permeate zone. Whereas at 360°C the yield of high-purity hydrogen in a reactor containing a membrane with a cleaned surface increased by just 15%, membrane surface cleaning by lamp processing ensured a 15‑fold gain at 260°C. This is due to the considerable difference between the hydrogen permeabilities of the membranes at low temperatures and its gradual decrease at high temperatures.
We consider nucleon-decay-like signatures of hylogenesis, a variant of the antibaryonic dark matter model. For the interaction between visible and dark matter sectors through the neutron portal, we ...calculate the rates of dark matter scatterings off a neutron which mimic neutron-decay processes n arrow right nu gamma and n arrow right nue super(+)e super(-) with richer kinematics. We obtain bounds on the model parameters from nonobservation of the neutron decays by applying the kinematical cuts adopted in the experimental analyses. The bounds are generally (much) weaker than those coming from the recently performed study of events with a single jet of high transverse momentum and missing energy observed at the LHC. Then we suggest several new nucleon-decay-like processes with two mesons in the final state and estimate (accounting for the LHC constraints) the lower limits on the nucleon lifetime with respect to these channels. The obtained values appear to be promising for probing the antibaryonic dark matter at future underground experiments like HyperK and DUNE.
—
The phase composition, texture, and substructure of foil of a Cu–36.4 at % Pd solid solution have been studied by X-ray diffractometry and electron diffraction after rolling to a thickness of 320, ...220, 180, 100, and 30 μm and subsequent heat treatment in vacuum to a temperature exceeding the upper temperature stability limit of an ordered structure. The results demonstrate that the general trends of changes in texture observed at all foil thicknesses during both deformation and subsequent heat treatment are controlled by ordering processes according to the Bain model and disordering processes, with allowance for the role of rolling deformation and recrystallization during subsequent heat treatment. At all foil thicknesses, heat treatment of the deformed samples leads to a decrease in the lattice parameter of the α-phase and an increase in that of the β-phase, suggesting an increase in the percentage of Pd in the β-phase and a decrease in that in the α-phase. The small change in the lattice parameter of the α-phase ensures the possibility of a complete α → β transformation.
We report on the results of model calculations for estimating the fragmentation effect in the registration of heavy and superheavy nuclei of galactic cosmic rays in olivine crystals from pallasite at ...the Marjalahti and Eagle Station. The measurement of fluxes and spectra of heavy and superheavy nuclei in cosmic rays is a sensitive method for studying the composition and possible sources of cosmic rays, the processes occurring in the sources themselves and in the interstellar medium, and forms the basis for constructing models of cosmic ray confinement in the Galaxy. The database obtained in the OLIMPIYA experiment, which includes characteristics of 21743 tracks, is the largest database for charges
Z
> 55 at present. The estimates of fragmentation of nuclei in pallasites, which have been obtained based on model calculations, show that the effect of this process on the resulting charge spectrum is insignificant.
Coronary occlusion (45 min) and reperfusion (120 min) in male Wistar rats
in vivo
, as well as total ischemia (45 min) of an isolated rat heart followed by reperfusion (30 min) were reproduced. The ...selective δ
2
-opioid receptor agonist deltorphin II (0.12 mg/kg and 152 nmol/liter) was administered intravenously 5 min before reperfusion
in vivo
or added to the perfusion solution at the beginning of reperfusion of the isolated heart. The peripheral opioid receptor antagonist naloxone methiodide and δ
2
-opioid receptor antagonist naltriben were used in doses of 5 and 0.3 mg/kg, respectively. It was found that the infarct-limiting effect of deltorphin II is associated with the activation of δ
2
-opioid receptors. We have demonstrated that deltorphin II can improve the recovery of the contractility of the isolated heart after total ischemia.
Diffusion filtering metallic palladium–yttrium membranes are subjected to hydrogenation from a gas phase and are studied by X-ray diffraction using synchrotron radiation. Boundaries of the formation ...of hydrogen-enriched phases are improved for a range of alloying component content, which is critical for their formation. The effect of the initial state of the alloy on conditions of hydride phase formation in the system is demonstrated. The content of hydrogen occluded in the membrane structure and hydrogen-induced lattice dilatations are determined. The parameters of the alloy substructure are calculated.
PDF
