New nonsymmetric dihetarylethenes were synthesized: 3-(5-methoxy-1,2-dimethyl-1
H
-indol-3-yl)-4-(3-thienyl)furan-2,5-dione and photochromic 1-alkyl-(1-aryl)-3-(5-methoxy-1,2-dimethyl-1
H
...-indol-3-yl)-4-(3-thienyl)-1(
H
)-pyrrole-2,5-diones. The absence of benzoannulation in the indole moiety results in the enhancement of the efficiencies of fluorescence and photocyclization of noncyclic isomers compared to the benzoindole derivatives.
There exists a great deal of concrete evidence in favor of the exotic four-quark nature of light scalars. At the same time, the further expansion of the area of the \(q^2\bar q^2\) model validity for ...light scalars on ever new processes seems extremely interesting and important. We analyze the BESIII data on the decay \(J/\psi\to \gamma\pi^0\pi^0\) and show that the results of this high-statistics experiment can be interpreted in favor of the four-quark nature of light scalar mesons \(f_0(980)\) and \(f_0(500)\).
MgB 2 -based bulk materials synthesized under 30 MPa-2 GPa pressure demonstrated an enhanced connectivity A F ~50%-98%,as compared tomostother reports (below50%), and a shielding fraction of ...75%-100%. The materials inhibit high critical current densities j c , but no strict correlation was found between A F and j c . On the other side, we found correlations between jc and the distribution of nanostructural inhomogeneities such as impurity oxygen in the form of oxygen-enriched Mg-B-O nanolayers or nanoinclusions and its solution in the MgB 2 matrix and as well with the amount and size of higher magnesium borides MgB x , x ≥ 4 inclusions. The distribution of boron- and oxygen-enriched (as compared to stoichiometric MgB 2 ) inhomogeneities affects the type of pinning and, thus, jc, and to some extent, it can be regulated by synthesis temperatures and pressures and by Ti addition. Auger spectroscopy, scanning electron microscopy, and X-ray with Rietveld refinement were used for structural study.
The influence of filler on the wear resistance of polymer composites is investigated. Three types of filler are considered: reinforcing fibers; short fibers; and disperse particles. Formulas for the ...proportion of the load on the polymer matrix permit optimization of the filler content in the composites, in the light of the frictional conditions.
A cross section of the process \(e^+e^- \to \pipi\pipi\) has been measured using 6798\(\pm\)93 signal events from a data sample corresponding to an integrated luminosity of 9.8 pb\(^{-1}\) collected ...with the CMD-3 detector in the center-of-mass energy range 920--1060 MeV. The measured cross section exhibits an interference pattern of the \(\phi(1020)\to\pipi\pipi\) decay with a non-resonant process \(e^+e^- \to \pipi\pipi\), from which we obtain the branching fraction of the doubly suppressed decays (by G-parity and OZI rule): \(\BR(\phi\to\pipi\pipi) = (6.5\pm2.7\pm1.6)\times 10^{-6}\).
The purpose - to optimize the quality of perioperative management of adolescents with damage of the anterior cruciate ligament of the knee. Material and methods: Perioperative methods of anesthesia ...in 71 patients were estimated. Psycho-emotional status was evaluated on the basis of determining the level of reactive anxiety (Spielberg Hanin scale) and intraoperative anesthesia (unilateral spinal anesthesia or combined) has been chosen. Results: According to the results of lactate and glucose levels in the blood the efficacy of unilateral spinal anesthesia during surgery was demonstrated. Visual analog scale revealed the advantage of extended continuous iliofascial block over an isolated femoral nerve blockade for adequate analgesia for postoperative period. The advantages of the performing continuous iliofascial block under ultrasound were demonstrated.
The effect of doping with Ti, Ta, SiC in complex with synthesis temperature on the amount and distribution of structural inhomogeneities in MgB2 matrix of high-pressure-synthesized-materials (2 GPa) ...which can influence pinning: higher borides (MgB12) and oxygen-enriched Mg-B-O inclusions, was established and a mechanism of doping effect on jc increase different from the generally accepted was proposed. Near theoretically dense SiC-doped material exhibited jc= 106 A/cm2 in 1T field and Hirr =8.5 T at 20 K. The highest jc in fields above 9, 6, and 4 T at 10, 20, and 25 K, respectively, was demonstrated by materials synthesized at 2 GPa, 600 °C from Mg and B without additions (at 20 K jc= 102 A/cm2 in 10 T field). Materials synthesized from Mg and B taken up to 1:20 ratio were superconductive. The highest jc (6×104 A/cm2 at 20 K in zero field, Hirr= 5 T) and the amount of SC phase (95.3% of shielding fraction), Tc being 37 K were demonstrated by materials having near MgB12 composition of the matrix. The materials with MgB12 matrix had a doubled microhardness of that with MgB2 matrix (25±1.1 GPa and 13.08±1.07 GPa, at a load of 4.9 N, respectively).
The relevance of this study is due to the fact that the accelerated development of industrial production combines the synergistic effects in natural and technological processes. The article deals ...with the problems of catastrophes mining regions of the North Caucasus and the method of determining the effectiveness of prevention of dangerous processes, based on the ratio of costs to eliminate the impact of disasters occurred and the costs of prevention of the occurrence of their occurrence.
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