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Betulin is a biologically active triterpenoid substance, which can be isolated from birch bark. We report on a new approach to the synthesis of betulin sulfamate with sulfamic acid and ammonium sulfamate in the presence of solid catalysts, including Amberlyst 15® and Sibunit (granules) oxidized at 500 °C, Sibunit (powder) oxidized at 400 °C, Sibunit-sulfated, TiO2, and ɣ-Al2O3. It is shown that the synthesis with both sulfamic acid and ammonium sulfamate in the presence of an Amberlyst 15® catalyst yields sulfur derivatives of betulin. This catalyst has been proven to remain active at the repeated (up to four cycles) use. A reaction scheme for the catalytic production of sulfur derivatives of betulin is proposed. The obtained sulfur derivatives of betulin have been examined by Fourier transform infrared and ultraviolet visible spectroscopy, scanning electron and optical microscopy, X-ray diffractometry, thermogravimetric analysis, differential scanning calorimetry, and elemental analysis. It has been found by Fourier transform infrared spectroscopy that the use of sulfamic acid with an Amberlyst 15® catalyst ensures the formation of betulin sulfates, while when using ammonium sulfamate with the same catalyst, the sulfate and other betulin derivatives are obtained along with sulfates. It has been established from the X-ray diffractometry data that sulfation of betulin causes its stronger amorphization.

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For the first time, the process of extraction fractionation of “hemicelluloses-free” birch wood in an ethanol medium into cellulose product and ethanol lignin is studied and optimized. The composition and structure of cellulose product and ethanol lignin obtained by extraction fractionation of “hemicellulose-free” birch wood and other products of their subsequent transformations are characterized by methods of infra-red spectroscopy, nuclear magnetic resonance, X-ray diffractometry, scanning electron microscopy, BET surface area analysis, high-performance liquid chromatography, gel permeation chromatography, gas chromatography, and chemical and elemental analysis. The possibility of producing enterosorbents from birch ethanol lignin that are more effective than the commercial enterosorbents “Polyphepan” based on hydrolyzed lignin is established. A new approach to the biorefinery of birch wood into xylose, levulinic acid and enterosorbents is proposed based on the integration of an optimized process of extraction fractionation of “hemicellulose-free” birch wood in ethanol medium, alkaline isolation of xylan and its hydrolysis to xylose, cellulose product conversion into levulinic acid and ethanol lignin processing to enterosorbents.

We propose an approach for describing the effective electronic states of atoms in compounds to study the properties of molecules and condensed matter, which are circumscribed by the operators heavily concentrated in atomic cores. Among the properties are hyperfine structure, space parity (P) and time reversal invariance (7) nonconservation effects, chemical shifts of x-ray emission lines (XES), Mössbauer effect, etc. An advantage of the approach is that a good quantitative agreement of predicted and experimental data can be attained even for such difficult cases as XES chemical shifts providing correct quantum-mechanical interpretation of the experimental data. From the computational point of view the method can be quite efficient being implemented in the framework of the relativistic pseudopotential theory [A. V. Titov and N. S. Mosyagin, Int. J. Quantum Chem. 71, 359 (1999)] and procedures of recovering the wave functions in heavy-atom cores [A. V. Titov, N. S. Mosyagin, A. N. Petrov, and T. A. Isaev, ibid. 104, 223 (2005)] after a molecular, cluster or periodic structure calculation performed on the basis of pseudo-orbitals smoothed near the nuclei within the pseudopotential approximation. We report results of our studies of a number of atomic and molecular systems to demonstrate the capabilities of the approach. [ABSTRACT FROM AUTHOR]

Relativistic ab initio calculations have been performed to assess the suitability of RaF for experimental search of P- and T-and-P-violating interactions. The parameters of P- and T,P-odd terms of the spin-rotational Hamiltonian have been calculated for the 2Σ electronic ground state of the 223RaF molecule. They include the Wa parameter, which is critical in the experimental search for nuclear anapole moment, and the parameters W4 and WSP required to obtain restrictions on the electric dipole moment of the electron and T,P-odd scalar-pseudoscalar interactions, respectively. The parameter X corresponding to the "volume effect" in the T,P-odd interaction of the 223Ra nuclear Schiff moment with electronic shells of RaF has also been computed. Spectroscopic and hyperfine structure constants for 223RaF and 223Ra+ have been computed as well, demonstrating the accuracy of the methods employed. [ABSTRACT FROM AUTHOR]

Strapdown inertial navigation systems (SINS) are basic parts of modern integrated navigation systems in various vehicles. Currently, fiber-optic gyroscopes (FOGs) with closed-loop feedback are finding increasing use for inertial navigation systems. The paper presents SINS-500K, SINS-500M and SINS-501 developed and produced by the Russian Research & Production Company Optolink with Optolink FOGs. The test results are discussed. Optolink FOGs and SINS’s are compared with similar devices of world leading manufacturers.

The current limit on the electron's electric dipole moment, |de|<8.7×10-29 ecm (90% confidence), was set using the molecule thorium monoxide (ThO) in the J=1 rotational level of its H³Δ1 electronic state [J. Baron et al., Science 343, 269 (2014)]. This state in ThO is very robust against systematic errors related to magnetic fields or geometric phases, due in part to its Ω-doublet structure. These systematics can be further suppressed by operating the experiment under conditions where the g-factor difference between the Ω doublets is minimized. We consider the g factors of the ThO H³Δ1 state both experimentally and theoretically, including dependence on Ω doublets, the rotational level, and the external electric field. The calculated and measured values are in good agreement. We find that the g-factor difference between Ω doublets is smaller in J=2 than in J=1 and reaches zero at an experimentally accessible electric field. This means that the H,J=2 state should be even more robust against a number of systematic errors compared to H,J=1. [ABSTRACT FROM AUTHOR]

The sensitivity of the PbF molecule to the electron electric dipole moment has motivated detailed microwave spectroscopy. Previous theoretical approaches cannot fully explain the spectra. In turn, the explanation from "first principles" is very important both for molecular theory and for confirmation of the correctness of the interpretation of experimental data obtained with high precision. All of these issues are decisively addressed here. We have determined centrifugal correction parameters for hyperfine structure constants, both on lead and fluorine nuclei, of the X2Y\\ß state of lead monofluoride. These parameters were obtained by fitting experimentally observed pure rotational transitions and from ab initio calculations. We show that taking this correction into account is required to reproduce the experimental transition energies obtained by R. J. Mawhorter et al. [ABSTRACT FROM AUTHOR]

We perform laser-induced fluorescence spectroscopy on a pulsed supersonic beam of tungsten carbide (WC) molecules, which has been proposed as a candidate molecular system for a permanent electric dipole moment (EDM) search of the electron in its rovibrational ground state of the X 3Δ1 state. In particular, [20.6]Ω = 2, v′ = 4 ← X 3Δ1 ,v″ = 0 transition at 485 nm was used for the detection. The hyperfine structure and the Ω doublet of the transition is measured, which are essential for estimating the size of the potential systematic uncertainties for electron EDM measurement. For further suppression of the systematic uncertainty, an alternative electron EDM measurement scheme utilizing the g factor crossing point of the Ω-doublet levels is discussed. On the other hand, flux and internal temperature of the molecular beam are characterized, which sets the limit on the statistical uncertainty of the electron EDM experiment. With the given results, the prospect of electron EDM experiment with the X 3Δ1 state of WC molecule is discussed. [ABSTRACT FROM AUTHOR]

The ten-electron generalized relativistic effective core potential and the corresponding correlation spin-orbital basis sets are generated for the Ra atom and the relativistic coupled-cluster calculations for the RaO molecule are performed. The main goal of the study is to evaluate the T, P-odd parameter X characterized by the molecular electronic structure and corresponding to a "volume effect" in the interaction of the 225Ra nucleus Schiff moment with electronic shells of RaO. Our final result for X(225RaO) is -7532 which is surprisingly close to that in 205T1F but has a different sign. The obtained results are discussed and the quality of the calculations is analyzed. The value is of interest for a proposed experiment on RaO [Phys. Rev. A 77, 024501 (2008)1 due to a very large expected Schiff moment of the 225Ra nucleus. [ABSTRACT FROM AUTHOR]

Abstract: The Hartree-Fock-Roothaan ab initio self-consistent average field method has been used in calculating the pair interaction potentials for atoms in the P2 and GaP molecules. The gallium and phosphorus atoms are considered in their ground states. The calculations agree well with experiment.

Abstract: The effect of heating rate on the density, water absorption, and the Young’s modulus of ceramic materials based on clays of different mineralogic compositions is studied. It is established that the optimum heating rate depends on the mineralogic composition and the functional parameters of ceramics.

Regulatory peptides are one of the main signaling molecules that provide intercellular interactions in biological systems. Thus, regulatory peptides are known as morphogens - biologically active substances involved in the regulation of the morphogenesis of animals and plants. Until now, the interaction of plant and animal peptides and, in particular, the 'cross' effect of plant peptides on the morphogenesis of animals and vice versa has not been sufficiently investigated. The present work is devoted to the study of the effect of growth regulator peptide (CLV 3) of Arabidopsis on the morphogenesis of animals - freshwater flatworms - planaria. This peptide is an effective regulator of growth and differentiation of plant roots in low and ultra-low concentrations. Various biophysical methods have shown that this plant peptide at a concentration of 10[?]9M is also an effective morphogen of animals. At the same time, the specificity of the action of peptides on 'unrelated' biological targets has been found. The peptide CLV 3 stimulates on the morphogenesis of plant roots in concentrations up to 10[?]12M, while for planarian regeneration it acts only at concentrations up to 10[?]9M, at which it does not show a noticeable effect on root plant growth. When this peptide was applied to the of stem human stem cells Th culture, there was no effect observed. The results of the study confirm the thesis that there is a general biological level and peptide regulation mechanisms that are similar for animals and plants, and also reveal the nature of the specifics of the 'direct' and 'cross' action of this mechanism.

A theoretical study devoted to suppression of magnetic systematic effects in HfF+ cation for an experiment to search for the electron electric dipole moment is reported. The g factors for J=1, F=3/2, |MF|=3/2 hyperfine levels of the ³Δ1 state are calculated as functions of the external electric field. The minimal value for the difference between the g factors of Ω-doublet levels, Δg=3×10-6, is attained at the electric field 7 V/cm. The body-fixed g factor, G∥, was obtained both within the ab initio electronic structure calculations and with our fit of the experimental data [H. Loh, K. C. Cossel, M. C. Grau, K.-K. Ni, E. R. Meyer, J. L. Bohn, J. Ye, and E. A. Cornell, Science 342, 1220 (2013)]. For the electronic structure calculations we used a combined scheme to perform correlation calculations of HfF+, which includes both the direct four-component all-electron and generalized relativistic effective core potential approaches. The electron correlation effects were treated using the coupled cluster methods. The calculated value G∥=0.0115 agrees very well with the G∥=0.0118 obtained with our fitting procedure. The calculated ab initio value D∥=-1.53 a.u. for the molecule-frame dipole moment (with the origin in the center of mass) is in agreement with the experimental datum D∥=-1.54(1) a.u. [H. Loh, Ph.D. thesis, Massachusetts Institute of Technology, 2006.]. [ABSTRACT FROM AUTHOR]