A lithium experiment in the program of solar neutrino research

Experiments sensitive to pp neutrinos from the Sun are very promising for precise measurement of the mixing angle ϑ ₁₂. A νe ⁻ scattering experiment (XMASS) and/or a charged-current experiment (indium detector) can measure the flux of electron pp neutrinos. One can find the total flux of pp neutrinos from a luminosity constraint after the contributions of ⁷Be and CNO neutrinos to the total luminosity of the Sun are measured. A radiochemical experiment utilizing a lithium target has high sensitivity to the CNO neutrinos; thus, it has a good promise for precise measurement of the mixing angle and for a test of the current theory of evolution of the stars. The text was submitted by the authors in English.     

Automated millimeter-wave-therapy devices of the “BAYuR” series and diagnostic and therapeutic systems based on them

The devices and systems for EHF therapy and diagnosis of the BAYuR series are examined and compared with known analogs.Scientific-Research Measuring-Systems Institute. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 37, No. 1, pp. 155–157, January, 1994.     

High-resolution four-dimensional 1H-13C NOE spectroscopy using methyl-TROSY, sparse data acquisition, and multidimensional decomposition

An approach for recording four-dimensional (4D) methyl (1)H-(13)C-(13)C-(1)H NOESY spectra with high resolution and sensitivity is presented and applied to Malate Synthase G (723 residues, 82 kDa). Sensitivity and resolution have been optimized using a highly deuterated, methyl-protonated sample in concert with methyl-TROSY, sparse data sampling in the three indirect dimensions, and 4D spectral reconstruction using multidimensional decomposition (MDD). A sparse data acquisition protocol is introduced that ensures that sufficiently long indirect acquisition times can be employed to exploit the decreased relaxation rates associated with methyl-TROSY, without increasing the duration of the 4D experiment beyond acceptable measurement times. In this manner, only a fraction ( approximately 30%) of the experimental data that would normally be needed to achieve a spectrum of high resolution is acquired. The reconstructed 4D spectrum is of similar resolution and sensitivity to three-dimensional (3D) (13)C-edited NOE spectra, is straightforward to analyze, and resolves ambiguities that emerge when 3D data sets only are considered.     

Off-resonance R(1rho) NMR studies of exchange dynamics in proteins with low spin-lock fields: an application to a Fyn SH3 domain

An (15)N NMR R(1rho) relaxation experiment is presented for the measurement of millisecond time scale exchange processes in proteins. On- and off-resonance R(1rho) relaxation profiles are recorded one residue at a time using a series of one-dimensional experiments in concert with selective Hartmann-Hahn polarization transfers. The experiment can be performed using low spin-lock field strengths (values as low as 25 Hz have been tested), with excellent alignment of magnetization along the effective field achieved. Additionally, suppression of the effects of cross-correlated relaxation between dipolar and chemical shift anisotropy interactions and (1)H-(15)N scalar coupled evolution is straightforward to implement, independent of the strength of the (15)N spin-locking field. The methodology is applied to study the folding of a G48M mutant of the Fyn SH3 domain that has been characterized previously by CPMG dispersion experiments. It is demonstrated through experiment that off-resonance R(1rho) data measured at a single magnetic field and one or more spin-lock field strengths, with amplitudes on the order of the rate of exchange, allow a complete characterization of a two-site exchange process. This is possible even in the case of slow exchange on the NMR time scale, where complementary approaches involving CPMG-based experiments fail. Advantages of this methodology in relation to other approaches are described.     

Morphology of Composite Films Based on Poly(N-vinylcaprolactam) with Titanium Dioxide Nanoparticles

Crystallography Reports - PVCL25 and PVCL40 films have been synthesized by poly(N-vinylcaprolactam) (PVCL) aqueous solution flow coating and complete desiccation below...     

Effect of thermal aging on the mechanical characteristics of a composite of a polyimide with an organosilicon resin

The effect exerted by thermal aging in air at 350°C on the thermal and mechanical properties of composite films prepared on the basis of heat-resistant polyimide PM and non-film-forming polymethylphenylsiloxane (PMPS) was examined. The phase segregation of polymeric composites of various compositions and the thermal aging rate were evaluated.     

Accelerated Nuclear Magnetic Resonance Spectroscopy with Deep Learning

Nuclear magnetic resonance (NMR) spectroscopy serves as an indispensable tool in chemistry and biology but often suffers from long experimental times. We present a proof‐of‐concept of the application of deep learning and neural networks for high‐quality, reliable, and very fast NMR spectra reconstruction from limited experimental data. We show that the neural network training can be achieved using solely synthetic NMR signals, which lifts the prohibiting demand for a large volume of realistic training data usually required for a deep learning approach.     

Study of the process of PbS nanocrystal formation in lead stearate and behenate Langmuir-Blodgett films by electron diffraction and x-ray reflectometry

Special features of the formation of PbS nanocrystals in Langmuir-Blodgett (LB) films of lead stearate and behenate under the action of H₂S are studied. It is shown that structural transformations in a multilayered LB film can be controlled using electron diffraction patterns of the oblique-texture type and x-ray reflectometry data.     

Nanocomposite: Antimony Sulfide in Channels of Single-Walled Carbon Nanotubes

A nanocomposite of antimony sulfide Sb₂S₃ embedded into the channels of single-walled carbon nanotubes (SWCNTs) has been prepared for the first time by the capillary wetting method and has been characterized by X-ray powder diffraction, transmission electron microscopy (TEM), transmission scanning electron microscopy (TSEM), and X-ray energy dispersive (EDX) spectroscopy. Antimony sulfide fills the channels of almost all SWCNTs. Channel filling is continuous along the entire length of the tube up to 1 μm. The diameters of filled SWCNTs fall in the range 0.6–3.5 nm. The periodicity of Sb₂S₃ crystal clusters observed on electron microscopic images is 2.0–2.2 nm along the nanotube axis and 2.5–3.5 nm in the transverse direction. A structural model of a Sb₂S₃ cluster is suggested.