Reprocessing of spent nuclear fuel (SNF) is an important task in a frame of ecology and rational use of natural resources. Uranium, as the main component of SNF (>95%), can be recovered for further ...use as fresh nuclear fuel. To minimize an amount of solid radioactive waste generated during SNF reprocessing, new extractants are under investigation. Diamides of 1,10-phenanthroline-2,9-dicarboxylic acid are perspective tetradentate N-donor ligands that form strong complexes with f-elements, which are soluble in polar organic solvents. As an example of three ligands of this class, we conducted a comparative study and showed how the substituent in the amide functional group affects the extraction ability toward uranyl nitrate from nitric acid media. We have performed a careful study (NMR, FT-IR, XRD, RMC-EXAFS) of the structures of synthesized complexes of new ligands with uranyl nitrate and used quantum mechanical calculations to explain the discovered regularities through.
Plasma membrane H
+
-ATPase (PMA1), the key enzyme of the yeast metabolism, undergoes multiple phosphorylation while maturating and functioning. In the cource of this process, the ATPase is getting ...activated (glucose effect). We have employed site-directed mutagenesis to determine the functional role of potentially phosphorylable amino acid residues located in the extracytosolic L9-10 loop (846-SENWTD). The mutant enzyme forms were expressed at the plasma membrane to examine the effect of substitutions on the ATPase biogenesis and activity. Immunobloting revealed that the mutant ATPase expression was not significantly impaired. In the absence of glucose, basal activity of the mutant enzymes differed insignificantly from that of the wild type. At the same time, regulation of the mutant E847A, T850A, and D851A enzymes has been impaired; the level of the enzyme activation by glucose was lower by 2.0–2.5-fold. On the contrary, S846A mutant displayed elevated basal activity maintaining the ability to undergo futher activation. These data indicate that these residues (especially, Ser-846, Thr-850, and Asp-851) are essential for the normal functioning of the PMA1 and its regulation by glucose.
In the present work, an improved model of the Raman gas analyzer (RGA) of natural gas (NG) developed by us is described together with its operating principle. The sensitivity has been improved and ...the number of measurable gases has been expanded. Results of its approbation on a real NG sample are presented for different measurement times. A comparison of the data obtained with the results of chromatographic analysis demonstrates their good agreement. The time stability of the results obtained using this model is analyzed. It is experimentally established that the given RGA can reliably determine the content of all molecular NG components whose content exceeds 0.005% for 100 s; moreover, in this case the limiting sensitivity for some NG components is equal to 0.002%.
The paper presents nonlinear backstepping approach for nonlinear control design applied to a DC motor driven inverted pendulum system. The nonlinear closed-loop system designed simultaneously tracks ...exponentially desired reference trajectory with overdamped response specifications. A simulation example is given for illustration.
We trace what happens with asymptotically free behavior of the running coupling in φ3 theory in six-dimensional spacetime, if to compactify two spatial dimensions on a 2D closed manifold. The result ...can be considered as an effective 4D theory of infinitely many KK-type scalar fields with triple interactions. The effective dimensional coupling constant inherits running to zero at high mass scales in a modified form depending on the size of the compact manifold. Some physical implications are discussed.
Gut microbiota of patients with Parkinson’s disease and healthy volunteers was analyzed by the method of high throughput 16S rRNA sequencing of bacterial genomes. In patients with Parkinson’s ...diseases, changes in the content of 9 genera and 15 species of microorganisms were revealed: reduced content of
Dorea
,
Bacteroides
,
Prevotella
,
Faecalibacterium
,
Bacteroides massiliensis
,
Stoquefichus massiliensis
,
Bacteroides coprocola
,
Blautia glucerasea
,
Dorea longicatena
,
Bacteroides dorei
,
Bacteroides plebeus
,
Prevotella copri
,
Coprococcus eutactus
, and
Ruminococcus callidus
, and increased content of
Christensenella
,
Catabacter
,
Lactobacillus
,
Oscillospira
,
Bifidobacterium
,
Christensenella minuta
,
Catabacter hongkongensis
,
Lactobacillus mucosae
,
Ruminococcus bromii
, and
Papillibacter cinnamivorans
. This microbiological pattern of gut microflora can trigger local inflammation followed by aggregation of α-synuclein and generation of Lewy bodies.
A simple and reliable approach for determining initial parameters in the problem of resonance Lorentzian curve approximation has been suggested. The algorithm has been applied to experimental data ...and its validity is shown. The results of iterative approximation with initial parameters that are found using proposed algorithm have been compared with those of approximation by the well-known Circle Fit algorithm. The suggested approach makes it possible to reduce signal-to-noise ratio requirements without loss of approximation reliability.
The paper presents the results of a comprehensive study on the optimization of independent amplitude and phase wavefront manipulation which is implemented using a binary digital micromirror device. ...The study aims to investigate the spatial resolution and quantization achievable using this approach and its optimization based on the parameters of the target complex wave and the modulation error estimation. Based on a statistical analysis of the data, an algorithm for selecting parameters (carrier frequency of binary pattern and aperture for the first diffraction order filtering) that ensures the optimal quality of the modulated wavefront was developed. The algorithm takes into account the type of modulation, that is, amplitude, phase, or amplitude-phase, the size of the encoded distribution, and its requirements for spatial resolution and quantization. The results of the study will greatly contribute to the improvement of modulated wavefront quality in various applications with different requirements for spatial resolution and quantization.
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