Begell House Inc.
Nanoscience and Technology: An International Journal
NST
2572-4258
9
2
2018
NANOTECHNOLOGICAL ASPECTS OF TEMPERATURE-DEPENDENT DECOMPOSITION OF POLYMER SOLUTIONS
91-97
Nikolay A.
Bulychev
Lebedev Physical Institute, Russian Academy of Sciences, 53 Leninsky Ave.,
Moscow, 119991, Russia; Moscow Aviation Institute, 4 Volokolamskoe Highway, Moscow, 125993, Russia
E. L.
Kuznetsova
Moscow Aviation Institute (National Research University), 4 Volokolamskoe
Highway, Moscow, 125933, Russia
V. V.
Bodryshev
Moscow Aviation Institute, 4 Volokolamskoe Highway, Moscow, 125993, Russia
Lev N.
Rabinskiy
Moscow Aviation Institute, 4 Volokolamskoe Highway, Moscow, 125993, Russia
In this paper, polymer deposition on a substrate upon exceeding the lower critical solution temperature
or on cooling beyond the upper critical solution temperature of poly(oxyethylene-boxypropylene-b-oxyethylene) 3-block copolymers has been studied. The decomposition mechanism
and the lower critical solution temperature inducing polymer deposition for modifying the surface of particles have been demonstrated.
OHMIC-VISCOUS DISSIPATION AND SLIP EFFECTS ON NANOFLUID FLOW OVER A STRETCHING CYLINDER WITH SUCTION/INJECTION
99-115
Ashish
Mishra
Department of Mathematics, Statistics and Computer Science, G.B. Pant University of
Agriculture and Technology, Pantnagar, Uttarakhand, India-263145
Alok Kumar
Pandey
Department of Mathematics, Statistics and Computer Science, G.B. Pant University of Agriculture and Technology, Uttarakhand-263145, India; Department of Mathematics, Roorkee Institute of Technology, Roorkee, Uttarakhand-247667, India
Manoj
Kumar
Department of Mathematics, Statistics and Computer Science, G.B. Pant University
of Agriculture and Technology, Pantnagar, Uttarakhand, India 263145
The present study investigates the consequences of viscous and ohmic dissipation, heat generation/absorption, and slip on MHD flow of silver–water nanofluid past a stretching cylinder in the regions of suction and injection. The set of acquired ODEs have been elucidated with assisting
boundary conditions by utilizing the Runge–Kutta–Fehlberg integration system nonlinear numerical approach via a shooting technique. The impact of relevant parameters on nondimensional flow and thermal fields is illustrated by graphs and elucidated in detail. Also, the dimensionless
skin friction coefficient and heat transfer rate are established in tabular way. The upshots reveal that in the temperature distribution field, an increasing value of velocity slip decreases in the suction region while it confirms dual nature in the injection region.
MODELING THE EFFECTIVE DYNAMIC PROPERTIES OF FIBER COMPOSITES MODIFIED ACROSS LENGTH SCALES
117-138
Dmitriy B.
Volkov-Bogorodsky
Institute of Applied Mechanics, Russian Academy of Sciences, 7 Leningradsky
Ave., Moscow, 125040, Russia
Sergey A.
Lurie
Institute of Applied Mechanics, Russian Academy of Sciences, 7 Leningradsky Ave., Moscow, 125040, Russia; Dorodnicyn Computing Centre FIC IU of the Russian Academy of Sciences, 40 Vavilov Str., Moscow, 119333, Russia
G. I.
Kriven
Moscow Aviation Institute (Technical University), 4 Volokolamskoe Highway,
Moscow, 125045, Russia
In the present work, we aim to estimate the effective storage and loss moduli of bristled fiber composite material (modified composites), where the surfaces of fibers are radially grown or coated with nanostructures such as nanowires, nanorods, or carbon nanotubes (fuzzy fiber). We
use the Eshelby integral formula, which plays a fundamental role in the micromechanics of composite materials and especially in gradient models of micromechanics that allow one to describe the scale effects. In a two-phase composite system, the use of an integral formula in the framework
of a generalized self-consistent scheme allows accurate closed-form solutions of effective properties for the interphase layer and for the composite as a whole. We employ a variant of generalized Eshelby's homogenization method to deduce effective damping properties of multilayer
nanostructured fiber composites where one layer is highly heterogeneous with respect to its mechanical response strain gradients. The novelty of the work lies in the fact of treating the ZnO nanowires and CNT "fuzzy" layers by the gradient model that consequently allows us to consider
the extra gradient coefficient or internal length in relation to other constitutive and geometric
parameters of the composite to definition of its overall mechanical and dynamical properties and functionality.
SYSTEMATIC STUDY OF STRUCTURAL AND CONDUCTIVE PROPERTIES OF COPPER NANOTUBES MODIFIED BY IONIZING RADIATION
139-153
I.
Kenzhina
Institute of Nuclear Physics of the Republic of Kazakhstan, Astana, Kazakhstan; L.N. Gumilyov Eurasian National University, Astana, Kazakhstan
Artem
Kozlovskiy
Institute of Nuclear Physics of the Republic of Kazakhstan, Astana, Kazakhstan; L.N. Gumilyov Eurasian National University, Astana, Kazakhstan
M.
Kaikanov
National Laboratory Astana, Astana, Kazakhstan
M.
Zdorovets
Institute of Nuclear Physics of the Republic of Kazakhstan, Astana, Kazakhstan; L.N. Gumilyov Eurasian National University, Astana, Kazakhstan; Ural Federal University named after the First President of Russia B.N. Yeltsin,
Yekaterinburg, Russia
A. V.
Tikhonov
Nazarbayev University, School of Science and Technology, Astana, Kazakhstan
In the modern materials science, irradiation by electron beams and by a γ-ray flux of metallic nanostructures is an effective tool for stimulating controlled modification of the structural and conductive properties of materials. The paper presents the results of investigation of the influence
of various types of irradiation on the structural and conductive properties of copper nanotubes obtained by electrochemical synthesis in pores of template matrices based on polyethylene terephthalate. The SEM, XRD, and EDS methods established that irradiation by an electron beam
and γ rays with doses of 50 and 100 kGy allows modifying the crystal structure of nanotubes, increasing their conductivity, and decreasing their resistance without destroying their structure. An increase in the irradiation dose leads either to an insignificant change in the conductive properties for high-energy electrons and γ quanta, or to a deterioration of the conductive properties
due to the appearance of oxide compounds in the crystal structure and to subsequent destruction of samples.
EFFECT OF THE PHASE STATE OF A POLYMER MATRIX ON THE DEGREE OF REINFORCEMENT OF POLYMER ORGANOCLAY NANOCOMPOSITES
155-163
Georgii V.
Kozlov
Kh.M. Berbekov Kabardino-Balkarian State University, 173 Chernyshevsky
Str., Nal'chik, 360000, Russia
Yulia N.
Karnet
Institute of Applied Mechanics, Russian Academy of Sciences,
7 Leningradsky Ave., Moscow, 125040, Russian Federation
I. V.
Dolbin
Kh.M. Berbekov Kabardino-Balkarian State University, 173 Chernyshevsky
Str., Nal'chik, 360000, Russia
A. N.
Vlasov
Institute of Applied Mechanics, Russian Academy of Sciences,
7 Leningradsky Ave., Moscow, 125040, Russian Federation
The article shows that a significant decrease in the modulus of elasticity of a polymer matrix in its transition from a vitreous state to an elastomeric state determines the same decrease in the modulus of elasticity of organoclay tactoids. An increase in the efficiency of a nanofiller for elastomeric matrices in comparison with vitreous matrices is conditioned by the change in the nanocomposite
structure as a whole, characterized by its fractal dimensionality. The effectiveness of a nanofiller is determined by its ability to generate interfacial regions. The mixture rule in its simplest form correctly describes the modulus of elasticity of nanocomposites, provided that the real, rather than the nominal modulus of elasticity of organoclay tactoids is used.
NANOSTRUCTURAL MODEL OF SHAPE MEMORY ALLOY WITH RESISTANCE ASYMMETRY BEHAVIOR
165-181
Ilya V.
Mishustin
Institute of Applied Mechanics, Russian Academy of Sciences, 7 Leningradsky Ave.,
Moscow, 125040, Russia
The behavior of shape memory alloys (SMAs) depends substantially on the type of stress-strain state. For example, under active tension and compression of initially chaotic martensite, the martensitic inelasticity curves differ both in absolute values and in shape. A flat sloping section of the curve like on yield plateau is present under tension and is absent in the case of compression.
A nonlinear model of polycrystalline SMA phase-structural deformation that takes into account the martensite nanostructure is proposed using the hypothesis of heterogeneous strain hardening of a representative volume and an analogue of the incremental plasticity theory with
isotropic and translational hardening to describe the structural transformation. Two dimensionless
parameters proportional to the ratio of deviator's third invariant to the cube of intensity of the inelastic strain tensor and active stress tensor are introduced to take into account the type of strain and stress state, respectively. The parameter of martensitic volume isotropic hardening
is lifetime maximum of the ratio of inelastic strain intensity to its limit value corresponding to the current strain state type. The material function of translational hardening depends on the full stress intensity and stress state type. The test modes of SMA loading to the determination of the functions used in the model are described. Special cases of SMA martensitic inelasticity in
a homogeneous stress state and corresponding simplifications of the basic equations are considered. The first case relates to the proportional loading of a specimen, the second one relates to the axial tension–compression and torsion of a thin-walled cylindrical rod.