The structure and properties of cold-rolled strips with a thickness of 3 mm from an experimental aluminum alloy 1580 with a lower scandium content of 0.03% (wt.) relative to the grade of the aluminum ...alloy and a 5083 similar alloy without scandium were studied. Ingots obtained at the laboratory installation of semicontinuous casting of the foundry department of the Siberian Federal University (Siberian Federal University, Russia, Krasnoyarsk) were used. The preparation of ingots for rolling included milling up to sizes of 40 × 100 × 145 mm and annealing according to a two-stage mode: at a temperature of 350 °C for 3 h (first stage) and at a temperature of 425 °C for 4 h (second stage). Hot rolling was carried out in the laboratory of the Department of Metal Forming at the Siberian Federal University at a temperature of 450 °C on a two-roll hot rolling mill with a roll diameter of 330 mm and a barrel length of 520 mm to a thickness of 5 mm, which corresponded to a total reduction of 88% with a single reduction of 2–5%. For cold rolling, a two-roll sheet rolling mill with a roll diameter of 200 mm and a barrel length of 400 mm grade LS 400 AUTO was used. Rolling was carried out to a thickness of 3 mm with a single reduction of 2–5%, and then the strip was annealed. The results of determining the mechanical properties by tension by the universal LFM400 machine showed that with an increase in the annealing temperature in the range from 250 to 350 °C for 3 h, ultimate tensile strength of the cold-rolled strips of aluminum alloy 1580 decreases from 385 to 365 MPa. For aluminum alloy 5083, a decrease in this strength characteristic is also observed from 345 to 320 MPa. A decreasing tendency with increasing annealing temperature was also observed for the conditional yield strength
R
p
, and over the entire range of annealing temperatures, the values of
R
p
for strips of alloy 1580 were higher than for alloy 5083 by 35–40 MPa, which amounted to 14–17% The values of the plastic properties, for which the value of the elongation to failure was analyzed, were close throughout the range of annealing temperatures for both alloys. The results of the analysis of micro- and fine structure allowed to conclude that an increase in the strength properties of cold-rolled and annealed sheets from the experimental alloy 1580, compared with alloy 5083, is a consequence of the addition of scandium in the experimental alloy 1580, which leads to an increase in the temperature of recrystallization of the alloy, preserving it contains a subgrain structure and dispersion hardening caused by precipitation of Al
3
(Sc, Zr) phase particles during the decomposition of a solid solution.
The dynamics of the parameters of the diffraction peak 0012 of LiNbO
3
:Fe crystals was recorded with a time resolution of less than 1 ns using synchronization of nanosecond laser pulses with ...synchrotron bunches of the KISI-Kurchatov source. The impact of a laser pulse (λ = 532 nm, τ = 4 ns, energy density 0.6 J/cm
2
) at different polarization directions of laser radiation causes a change in the peak intensity; this change depends on the angle between the laser beam polarization direction and the crystallographic axes. The obtained results are supplemented with the wavelet analysis of experimental data. The observed polarization dependence correlates with the data in the literature on the photovoltaic effect.
Measurement of Γee(J/ψ) with KEDR detector Anashin, V. V; Aulchenko, V. M; Baldin, E. M ...
The journal of high energy physics,
05/2018, Letnik:
2018, Številka:
5
Journal Article
Recenzirano
Odprti dostop
A
bstract
The product of the electronic width of the
J/ψ
meson and the branching fractions of its decay to hadrons and electrons has been measured using the KEDR detector at the VEPP-4M
e
+
e
−
...collider. The obtained values are
Γ
e
e
J
/
ψ
=
5.550
±
0.056
±
0.089
keV
,
Γ
e
e
J
/
ψ
·
ℬ
hadrons
J
/
ψ
=
4.884
±
0.048
±
0.078
keV
,
Γ
e
e
J
/
ψ
·
ℬ
e
e
J
/
ψ
=
0.3331
±
0.0066
±
0.0040
keV
.
The uncertainties shown are statistical and systematic, respectively. Using the result presented and the world-average value of the electronic branching fraction, one obtains the total width of the
J/ψ
meson:
Γ
=
92.94
±
1.83
keV
.
These results are consistent with the previous experiments.
A method to measure the velocity of subsonic submerged plasma jets with unstable flows based on an analysis of the motion of optical inhomogeneities introduced into the jet is considered. A source of ...these inhomogeneities in the form of a heat-resistant thin rod is placed in a diametrical direction of a chosen cross section of the jet flowing from the output channel of a high-current DC plasmatron into ambient air under atmospheric pressure. The plasma-forming gas is a mixture of argon and nitrogen, and the characteristic Reynolds numbers of the studied flows are Re
D
= 50–300. The perturbation effect of the body introduced into the plasma jet on the two most important characteristics (plasma temperature and velocity) was studied. Specific features of laminar and pulsating flows of submerged plasma jets were studied via two-site, high-speed, synchronous visualization. It is shown that the length of the continuity restoration part of the jet flowing around the rod at a temperature of 10–12 kK and a velocity of 100–500 m/s is very small (several millimeters) under these conditions. The plasma temperature in the region of the strongest thermal perturbation caused by the introduction of the rod was measured with spectral methods. The observed plasma cooling is compared with the calculated decrease in the enthalpy due to expenditures for the heating and ablation of the rod material.
Purpose: to provide clinical and morphological evaluation of the corneal epithelium phenotype in total vascular leukomas of varied etiologies and determine the optimal surgical treatment using ...impression cytology (IC).
Materials and methods. 44 patients (44 eyes) with corneal vascular leukomas of various etiologies underwent optic keratoplasty preceded by IС. The patients were divided into 2 groups according to IC findings. Group 1 included 30 patients who were shown by IC to have corneal epithelium. These patients received penetrating keratoplasty (PK). Group 2 consisted of 14 patients whose epithelium was determined to be of conjunctival phenotype. Eight of group 2 patients had their corneal epithelium phenotype restored by limbal transplantation followed by PK. The remaining patients of group 2 were not operated for various reasons.
Results. In the remote postoperative period (9–12 months after the operation) corrected visual acuity of group 1 patients ranged from 0.3 to 0.6 (ave. 0.450 ± 0.073). A relapse of corneal leukoma was observed in three patients of group 1 (10%). In group 2, a transparent vascular-free engraftment of keratotransplants was observed in 5 patients after limbal transplantation (the first stage of surgical treatment) and PK, their corrected visual acuity ranged from 0.1 to 0.5 (ave 0.37 ± 0.12), 1 (20%) patient had a relapse of the leukoma. C
onclusions. Impression cytology is an acceptable and low invasive diagnostic technique that allows clinical and morphological evaluation of the epithelium phenotype that covers the vascular leukoma and helps determine validated indications for the choice of a surgical treatment technique for such patients.
The focus of this paper is on the impedance-based fault location in a transmission line via synchronized phasor measurements. Physical and mathematical modeling involving real-time digital ...simulations is used to show that fault location based on synchronized phasor measurements is promising for extra-high voltage overhead transmission lines. Avariety of single-end and double-end fault location methods are put together to show that the fault location accuracy can be well within 1 – 2% for both P and M class filters defined in the IEEE C37.118 standard. The methods are analyzed for a validated 750 kV line model generated using ATPDraw software and an electric grid model with 500, 330, and 220 kV overhead lines sharing the same right-of-way. Unlike many other publications, no Fourier-simulated phasors under transients are used here. Instead, we resort to physical modeling involving hardware equipped with synchrophasor functionality. An experimental setup is described, and future research areas are highlighted.
The variety of research being conducted at the instruments on the external beams of the IBR-2M pulsed fast reactor in Frank Laboratory of Neutron Physics Joint Institute for Nuclear Research (FLNP ...JINR) is the reason of the differences in the requirements of the detectors for these instruments. This leads to the necessity of developing a variety of detectors in the Laboratory that are used in experiments. This report reviews the neutron detection systems developed and used at the instruments on the external beams of the IBR-2M pulsed research reactor, the current status and operating features of which have been considered.
The increased requirements to high-speed travelling-wave relay protective systems of high- and extra-high-voltage transmission lines are imposed for ensuring high reliability of interaction of ...protection algorithms and fault-phase selection detectors of single-phase automatic reclosings for the purpose of ensuring the necessary conditions for the maximum use of advantages of these protective systems. The discussion covers travelling-wave relay protection device operation principles, together with the fault-phase selection detector, in which the comparison of magnitudes of phase fault currents (voltages) of the transmission lines average in absolute values takes place. Criteria for selecting the response and return time of the travelling-wave protection directional elements and the fault-phase selection detectors are developed that allow improving the efficiency of operation of protection in the single-phase automatic reclosing cycle. It is shown that the response times of the fault-phase selection detector and the directional elements should be commensurate and the devices themselves should have the ability to detect not only the occurrence of a short circuit, but also the short circuit’s transition to more complex modes in the single-phase automatic reclosing cycle. In the open-phase mode of transmission line operation, the reset time of protection can be significantly reduced compared to the previously selected values due to the fact that the decay constants of the free periodic component are 30–50 ms and decrease with the component frequency and increase in transient resistance at the point of a short circuit.
The awareness of malignant metabolism transformations has recently emerged. Since Otto Warburg found that tumor cells prefer glycolysis to oxidative phosphorylation even in the presence of oxygen, ...studies have shown that cancer cells also depend on upregulated fatty-acid synthesis and glutaminolysis. The present review covers the key metabolic enzymes known as metabolic oncogenes and suggests ways of modulating their activity. It is concluded that metabolic transformations during carcinogenesis present opportunities for targeted action on neoplasms and provide a new field for antitumor drug development.
A method is proposed for integral assessment of the propagation of microbial cells and phage particles during seasonal thawing of relic ice wedge layers. The results of field and laboratory ...investigation carried out in the upper part of permafrost exposure at Mamontova Gora (Yakutiya, Russia) are presented. Suspensions of yeast, bacteria, and two coliphages were introduced as biomarkers directly on the surface of thawing ice and in the meltwater flow. Microorganisms and phages were shown (a) to possess particular parameters of dissemination in the meltwater flow and (b) were able to move 132 m in 25–35 min with the stream water flow.
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