Electrowetting of a gold electrode by alkali bromide and iodide melts

Journal of Solid State Electrochemistry - The potential dependence of the wetting angle on a gold electrode in sodium, potassium, and cesium bromide and iodide melts was studied to establish the...     

Positive Trend of Surface Ozone in the North of the Privolzhskii Federal Region of the Russian Federation

The results of long-term continuous measurements of surface ozone concentrations, performed in 2010–2016 in the relatively low-urbanized region in the north of the Privolzhskii Federal Region of the Russian Federation (Vyatskie Polyany, Kirov oblast) are presented. A regular increase in the amplitude of diurnal variations of yearly average surface ozone concentrations is detected. The possible causes of this phenomenon can be both an increase in the atmospheric concentration of pollutants, i.e., precursors of tropospheric ozone, and climatic changes.     

Local heating of a medium in the nanovicinity of the <Superscript>57</Superscript>Co nucleus that underwent radioactive decay to <Superscript>57</Superscript>Fe

Process of formation of the Auger blob (nanosized cloud of two or three hundred of ion–electron pairs) around a ⁵⁷Co radioactive atom after E-capture followed by the emission of a cascade of Auger electrons by the daughter atom ⁵⁷Fe has been considered. The effect of local temperature elevation in the Auger blob caused by energy emission during ionization slowing down of Auger electrons and the secondary electrons generated by them is discussed. Some consequences of this effect have been noted.     

Possible observation of light neutron nuclei in the alpha-particle-induced fission of 238U

Searches for nuclear-stable multineutrons among products originating from the fission of ²³⁸U nuclei that is induced by 62-MeV alpha particles were performed by the activation method. The reaction involving the transfer of four neutrons and occurring on the isotope ⁸⁸Sr, ⁸⁸Sr( ^x n, (x ? 4) n)⁹²Sr??⁹²Y, was used to identify nuclear-stable multineutrons. A line at the energy of E = 1384 keV was found in the measured gamma-ray spectra of irradiated samples. This line, together with the measured time dependence of the decrease in its activity, is indicative of the formation of the beta-active nucleus ⁹²Sr. This result was reproduced in repeated measurements. It suggests the possible existence of nuclear-stable multineutrons ( ^x n) for x ?? 6. The differential cross section for the ^x n yield at an angle of 30° in the alpha-particle-induced fission of ²³⁸U was about 6 × 10^?2 mb/sr.     

Superacid mediated hydroxyalkylation reaction of 1,2,3‐indanetrione: a theoretical study

Energies of mono‐ and multiprotonation for 1,2,3‐indanetrione and ninhydrin in triflic acid (TFSA) media were estimated at PBE0/aug‐cc‐pvtz//6‐31+G** level of theory. The reactivity of formed intermediates in the reaction of aromatic electrophilic substitution has been studied at the same level of theory. It appears that the basicity of carbonyl groups in 1,2,3‐indanetrione is extremely low due to mutual influences of carbonyl groups. Carbonyl 2 is the least basic but the most reactive in accordance with experiment. Calculations demonstrated that monoprotonated intermediates are the principal reactive species in the reaction of hydroxyalkylation of 1,2,3‐indanetrione in TFSA. A new isomerization mechanism of 2,2‐diaryl‐1,3‐indanediones to 3‐(diarylmethylene)isobenzofuranones in TFSA media has been proposed. Copyright © 2010 John Wiley & Sons, Ltd.     

Electrophysical and acoustic properties of magnetic elastomers structured by an external magnetic field

Magnetoactive elastomers are promising for use in designing of magnetically operated devices for signal processing and sensors. The results from studying the electrophysical and acoustic properties of new magnetoactive elastomers structured by a nonuniform magnetic field are presented. It is shown that the prestructuring of the magnetic disperse filler by a magnetic field during composite synthesis substantially improves the coefficient of the transmission of electromagnetic radiation through the sample. The effect gets stronger as the mass fraction of filler increases. As the filler concentration grows, the transmission coefficient falls by 50%, and the ref lection coefficient grows by a factor of 150%. The longitudinal elastic modulus and the density vary within the ranges of 1.4–1.8 GPa and 2485–3362 kg m^–3, respectively, depending on the magnetic filler concentration and the sample’s structuring. The obtained results demonstrate the potential of usinf structured magnetoactive elastomers as radar absorbing materials.     

Synthesis and Study of Spatial Structure 3,7-Bis(Dimethylamino)-5,10-Dihydrodibenzo-[b,e]- Phosphorines by NMR

Abstract

The phosphorines (VIII-XI) were obtained in the reaction 3,3-bis(dimethylamino)triphenylphosphine (I) and bis(3-dimethylaminophenyl) pentafluorophenylphosphorine (II) with benzaldehyde (III) and its 4-methoxy (IV), 4-dimethylamino (V), 2-fluro (VI), pentafluoro (VII) derivatives according to the scheme (1).     

An Improved Measurement of Isotopic Ratios by High Resolution Mass Spectrometry

The study of protein kinetics requires an accurate measurement of isotopic ratios of peptides. Although Fourier transform-ion cyclotron resonance (FT-ICR) mass spectrometers yield accurate mass measurements of analytes, the isotopologue ratios are consistently lower than predicted. Recently, we demonstrated that the magnitude of the spectral error in the FT-ICR mass spectrometer is proportional to the scan duration of ions. Here, we present a novel isotopic ratio extrapolation (IRE) method for obtaining accurate isotopic ratio measurements. Accuracy is achieved by performing scans with different duration and extrapolation of the data to the initial moment of the ion rotation; IRE minimizes the absolute isotopic ratio error to ≤1 %. We demonstrate the application of IRE in protein turnover studies using ²H₂O-metabolic labeling. Overall, this technique allows accurate measurements of the isotopic ratios of proteolytic peptides, a critical step for enabling routine studies of proteome dynamics.