232 research outputs found

    Effect of thermomechanical impacts on the deformation of thin polyimide films at uniaxial tension

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    Thermomechanical studies of the dependence of deformation on time (t) and temperature (T) for various static stresses in polyimide under uniaxial tension were carried out. Temporal deformation curves for static stresses in the range from 75 to 110 MPa consist of two stages: 1 - increase; 2 - exit to saturation, which is associated with a change in the nature of structural transformations of macromolecules, due to the action of the static stresses. An increase in temperature and voltage leads to an increase in the dependence e (Т). This is due to the intensification of the processes of structuring macromolecules with increasing temperature and are supplemented by processes of breaking bonds between macromolecules, which increase the strain rate. Experimental data are described in terms of exponential and linear models

    Influence of words in the sentence on the communicative function of a language (exemplified by the Russian and tajik languages)

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    A necessity in the development of the comparative grammar of the Russian and Tajik languages and a need in solving of many disputable issues of the syntactic knowledge, moreover, the lack of fundamental researches on comparative studying of the words order in Russian and Tajik allows to define our research as for actual. The objectives of the article are studying of the words order in Russian and Tajik within comparative and typological aspects formulization of peculiarities of interaction between the structural-grammar and actual aspects of studying of words order in sentences of the languages themselves. In order to achieve the objectives, the authors used a method of direct observation of word arrangement in texts when expressing the grammatical and logical base of the sentence; linguistic experiment the content whereof is various types of transformation; comparative method by means whereof differences are exposed in communicative structures of analyzed sentences, statements and types of words order in sentences and statements and descriptive method. Studying of variants of syntactic structures in the two languages expose national specificity of the semantics of the verbal execution of a statement in these consistencies/inconsistencies. The results allow expansion of theoretical knowledge of the role of words order and other means of actual articulation of a sentence in the Russian and Tajik languages as well as working out the theory of words order in sentences, the communicative structure of a sentence and functional grammar. © 2019, Slovenska Vzdelavacia Obstaravacia. All rights reserved

    Study of deformation dependence on time in polyethylene terephthalate for different static loads and irradiation doses

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    Complex experiments were conducted on deformation dependence on time for different static loads and irradiation doses in polyethylene terephthalate. Curves of time (t) dependence of deformation (?) show a significant change in the behavior of the material after irradiation. The obtained dependence curves of on t for both non-irradiated and irradiated materials are satisfactorily described by cascade-probability model

    Biosimilars: development and investigation using achievements in modern biotechnology

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    Biosimilars are biological drug products that have an equivalent clinical profile with innovator biotherapeutics but are developed under a reduced program. To this end, specific comparability approaches are followed based on reverse engineering that involves a thorough analysis of the innovator biotherapeutics and the development of the version of the latter, which should be as much as possible similar with respect to structural and functional characteristics with the innovator. This approach includes the evaluation and comparison between the biosimilar and innovator biologic with respect to the molecular structure and impurity profile and of biological activity in in vitro settings as well as pharmacokinetic, pharmacodynamic, and immunogenicity characteristics on human subjects. Where considered necessary, animal studies or phase 3 clinical studies might be performed when residual uncertainties remain in terms of biosimilarity, that could not have been resolved in the previous tests and trials. Any potentially inevitable differences should be insignificant for safety and efficacy. The state-of-the-art methods of biotechnology and analytics, when applied in line with the appropriate scientific and regulatory requirements, can allow developing similar biologics where no difference in the clinical profile exists with the respective innovator product. Available experience demonstrates the lack of major problems due to the incomparability between the biosimilar and corresponding reference biologics when applicable scientific standards and regulatory recommendations are met

    Study of the influence of the electron irradiation dose on the deformation of Mylar films taking into account the processes of destruction and crosslinking

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    Experimental studies of the dependence of the deformation [epsilon] on the dose of electron irradiation D taking into account the processes of destruction and crosslinking for films of the Mylar type have been carried out. It was obtained that the dependence of [epsilon] on D for the process of cross-linking is described by a linear and destruction by an exponential function

    Precise Measurement of the Neutron Magnetic Form Factor GnM in the Few-GeV² Region

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    The neutron elastic magnetic form factor was extracted from quasielastic electron scattering on deuterium over the range Q2 = 1.0–4.8  GeV2 with the CLAS detector at Jefferson Lab. High precision was achieved with a ratio technique and a simultaneous in situ calibration of the neutron detection efficiency. Neutrons were detected with electromagnetic calorimeters and time-of-flight scintillators at two beam energies. The dipole parametrization gives a good description of the dat

    Beam Spin Asymmetries in Deeply Virtual Compton Scattering (DVCS) With CLAS at 4.8 GeV

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    We report measurements of the beam spin asymmetry in deeply virtual Compton scattering (DVCS) at an electron beam energy of 4.8 GeV using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The DVCS beam spin asymmetry has been measured in a wide range of kinematics, 1.02\u3c2.8 (GeV/c)2, 0.12\u3cxB\u3c0.48, and 0.1\u3c−t\u3c0.8 (GeV/c)2, using the reaction →ep→e′pX. The number of H(e,e′γp) and H(e,e′π0p) events are separated in each (Q2,xB,t) bin by a fit to the line shape of the H(e,e′p)X M2x distribution. The validity of the method was studied in detail using experimental and simulated data. It was shown that with the achieved missing mass squared resolution and the available statistics, the separation of DVCS–Bethe-Heitler and π0 events can reliably be done with less than 5% uncertainty. Also, the Q2 and t dependences of the sinϕ moments of the asymmetry are extracted and compared with theoretical calculations

    Light Vector Mesons in the Nuclear Medium

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    The light vector mesons (ρ,ω, and ϕ) were produced in deuterium, carbon, titanium, and iron targets in a search for possible in-medium modifications to the properties of the ρ meson at normal nuclear densities and zero temperature. The vector mesons were detected with the CEBAF Large Acceptance Spectrometer (CLAS) via their decays to e+e−. The rare leptonic decay was chosen to reduce final-state interactions. A combinatorial background was subtracted from the invariant mass spectra using a well-established event-mixing technique. The ρ-meson mass spectrum was extracted after the ω and ϕ signals were removed in a nearly model-independent way. Comparisons were made between the ρmass spectra from the heavy targets (A\u3e2) with the mass spectrum extracted from the deuterium target. With respect to the ρ-meson mass, we obtain a small shift compatible with zero. Also, we measure widths consistent with standard nuclear many-body effects such as collisional broadening and Fermi motion

    Moments of the spin structure functions g(1)(p) and g(1)(d) for 0.05 \u3c Q\u3csup\u3e2\u3c/sup\u3e \u3c 3.0 GeV\u3csup\u3e2\u3c/sup\u3e

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    The spin structure functions g1 for the proton and the deuteron have been measured over a wide kinematic range in x and Q2 using 1.6 and 5.7 GeV longitudinally polarized electrons incident upon polarized NH3 and ND3 targets at Jefferson Lab. Scattered electrons were detected in the CEBAF Large Acceptance Spectrometer, for 0.05 \u3c Q2 \u3c 5GeV2 and W \u3c 3 GeV. The first moments of g1 for the proton and deuteron are presented – both have a negative slope at low Q2, as predicted by the extended Gerasimov–Drell–Hearn sum rule. The first extraction of the generalized forward spin polarizability of the proton γ p 0 the Q2 evolution of the first moment of g1 shows agreement in leading order with Heavy Baryon Chiral Perturbation Theory. However, a significant discrepancy is observed between the γ p 0 data and Chiral Perturbation calculations for γ p 0, even at the lowest Q2

    First Measurement of Beam-Recoil Observables C\u3csub\u3ex\u3c/sub\u3e and C\u3csub\u3ez\u3c/sub\u3e in Hyperon Photoproduction

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    Spin transfer from circularly polarized real photons to recoiling hyperons has been measured for the reactions →γ + p → K+ + →Λ and →γ+p → K+ + →Σ0. The data were obtained using the CEBAF Large Acceptance Spectrometer (CLAS) detector at the Jefferson Lab for center-of-mass energies W between 1.6 and 2.53 GeV, and for -0.85 \u3c cos θc.m.K+ \u3c +0.95. For the Λ, the polarization transfer coefficient along the photon momentum axis, Cz, was found to be near unity for a wide range of energy and kaon production angles. The associated transverse polarization coefficient Cx is smaller than Cz by a roughly constant difference of unity. Most significantly, the total Λ polarization vector, including the induced polarization P, has magnitude consistent with unity at all measured energies and production angles when the beam is fully polarized. For the Σ0 this simple phenomenology does not hold. All existing hadrodynamic models are in poor agreement with these results
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