34 research outputs found
Thin films of unsubstituted and fluorinated palladium phthalocyanines: structure and sensor response toward ammonia and hydrogen
In the present work, we study and compare the structure and sensing properties of thin films of unsubstituted palladium phthalocyanine (PdPc) and hexadecafluorosubstituted palladium phthalocyanine (PdPcF16). Thin films of PdPc and PdPcF16 were obtained by the method of organic molecular beam deposition and their structure was studied using UV-visible spectroscopy, X-ray diffraction and atomic force microscopy techniques. The electrical sensor response of PdPc films toward ammonia and hydrogen was investigated and compared with that of PdPcF16 films. The nature of interaction between the phthalocyanines films and some gaseous analyte molecules has been clarified using Quantum chemical (DFT) calculations
Effect of fluorosubstitution on the structure of single crystals, Effect of fluorosubstitution on the structure of single crystals,thin films and spectral properties of palladium phthalocyanines
In this work, the crystalline structure of single crystals grown by vacuum sublimation of unsubstituted palladium phthalocyanines (PdPc), its tetrafluorinated (PdPcF4) and hexadecafluorinated (PdPcF16) derivatives have been investigated using X-ray diffraction measurements. Two crystalline phases have been identified for PdPc; the molecules in both phases crystallize in stacks with herringbone arrangement in the monoclinic space groups (C2/c for -PdPc; P21/n for -PdPc). Both PdPcF4 and PdPcF16 crystallize in the triclinic P-1 space group, forming stacks of molecules in columnar arrangement with molecules in adjacent columns are aligned parallel to one another. X-ray diffraction measurements have also been used to elucidate the structural features and molecular orientation of thin films of PdPc, PdPcF4 and PdPcF16, grown by organic molecular beam deposition at different substrate temperatures. The effect of fluorosubstitution on UV-visible optical absorption and vibrational spectra of palladium phthalocyanine derivatives is also discussed
Application of Morse potential in nonlinear dynamics of microtubules
We here present a model of nonlinear dynamics of microtubules using modified extended tanh-function method as a mathematical tool. Interaction between neighbouring dimers belonging to a single protofilament is commonly modelled by a harmonic potential. In this paper, we introduce a more realistic Morse potential energy instead. We obtained three solitary waves as before, when the harmonic potential was used. However, the Morse potential allows transition from the state when elastic term in the expression for total energy is bigger than the inertial one to the state when the inertial potential is bigger. Also, three new solutions were obtained
Karyotypic variability in some species of the genus Chondrilla (Asteraceae)
Karyotypic variability of plants was evaluated in 17 populations of six species of the genus Chondrilla (C. ambigua Fisch., C. brevirostris Fisch, et Mey., C. laticoronata Leonova, C. canescens Kar., Kir., C. juncea, C. pauciflora Ledeb.) in the Astrakhan, Voronezh and Saratov regions, the Republic of Kalmykia, and Western Kazakhstan. It is maintained that C. ambigua is a strict diploid (2n = 2x = 10) species, while its close relative - C. pauciflora - is a strict triploid (2n = 3x = 15) taxon. The research demonstrates that the plants of the apomictic taxa C. brevirostris, C. canescens, C. juncea and C. laticoronata are characterized by the genomic instability in the form of chromosome instability which results in these species’ mixed-ploidy populations
Karyotypic variability in some species of the genus Chondrilla (Asteraceae)
Karyotypic variability of plants was evaluated in 17 populations of six species of the genus Chondrilla (C. ambigua Fisch., C. brevirostris Fisch, et Mey., C. laticoronata Leonova, C. canescens Kar., Kir., C. juncea, C. pauciflora Ledeb.) in the Astrakhan, Voronezh and Saratov regions, the Republic of Kalmykia, and Western Kazakhstan. It is maintained that C. ambigua is a strict diploid (2n = 2x = 10) species, while its close relative - C. pauciflora - is a strict triploid (2n = 3x = 15) taxon. The research demonstrates that the plants of the apomictic taxa C. brevirostris, C. canescens, C. juncea and C. laticoronata are characterized by the genomic instability in the form of chromosome instability which results in these species’ mixed-ploidy populations
Demodulated standing solitary wave and DNA-RNA transcription
Nonlinear dynamics of DNA molecule at segments where DNA-RNA transcription occurs is studied. Our basic idea is that the solitary wave, moving along the chain, transforms into a demodulated one at these segments. The second idea is that the wave becomes a standing one due to interaction with DNA surrounding, e.g., RNA polymerase molecules. We explain why this is biologically convenient and show that our results match the experimental ones. In addition, we suggest how to experimentally determine crucial constant describing covalent bonds within DNA. © 2018 Author(s)
Development and Application of Remote Laboratory for Embedded Systems Design
This paper devoted to Embedded Systems’ Hardware-Software CoDesign and an overview of approach based on using ready platforms. Comparable analysis of well-known platforms from different vendors is given. Application of remote laboratories of the embedded system rapid prototyping was offered. Remote lab architecture, set of experiments and use case scenario are described. Proposed approach improves the current state of the art in the area of embedded systems design allowing to accelerate stages of hardware-software integration and testing
Thermoelectric properties and cost optimization of spark plasma sintered n-type Si0.9Ge0.1 - Mg2Si nanocomposites
We report on thermoelectric properties of low Ge content n-type Si0.9Ge0.1–Mg2Si nanocomposite. Introduction of the Mg2Si phase into a SiGe matrix resulted in a dramatic drop of the lattice thermal conductivity beyond the previously reported lowest limit for SiGe alloys due to intensification of phonon scattering on SiGe–Mg2Si grain boundaries. For a sample doped with 1 at.% of Mg2Si, the peak value of thermoelectric figure of merit ZT reached ~ 0.8 at 800 °C. Sintered nanocomposites still exhibit high thermoelectric performance while being almost two times cheaper than Si0.8Ge0.2