Development of complex of mathematical models at production stages of multilayer structures of spherical shape by polymerization method

Polystyrene (PS)-based hybrid particles containing a large amount of Mg(OH)2powder treated with methylhydrogen polysiloxane (MHS) were fabricated by a bulk and subsequent suspension two-step polymerization method. All the particles fabricated showed spherical shape and their particle sizes were about 500 μm, irrespective of the additive amount of the Mg(OH)2powder modified with MHS (ST-1). The actual content of ST-1 powder incorporated inside each kind of hybrid particle was almost the same as that in the raw mixture, and agglomeration of ST-1 powder was hardly observed inside the hybrid particles. The compressive strength of the hybrid particles remained almost unchanged, even when the ST-1 powder content increased from 10 to 50 phr. Furthermore, a composite fabricated by employing the hybrid particles achieved homogenous distribution of ST-1 powder and showed a higher oxygen index than that of a composite fabricated by directly mixing of PS pellets and ST-1 powder.

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MATHEMATICAL MODELING OF NON-STATIONARY THERMAL CONDUCTIVITY IN THE THIRD STAGE OF PRODUCTION OF MULTILAYER STRUCTURES BY THE POLYMERIZATION METHOD WITH DIFFERENT THERMAL CONDUCTIVITY COEFFICIENTS

Scientific and Technical Volga region Bulletin ◽

10.24153/2079-5920-2017-7-5-112-115 ◽

2017 ◽

Vol 7 (5) ◽

pp. 112-115

Author(s):

I.A. Akimov ◽

◽

V.N. Abuzyarov ◽

Keyword(s):

Mathematical Modeling ◽

Thermal Conductivity ◽

Multilayer Structures ◽

The Third ◽

Third Stage ◽

Polymerization Method

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Macrostructure and microphysics of Saturn's E-ring

International Astronomical Union Colloquium ◽

10.1017/s0252921100101691 ◽

1984 ◽

Vol 75 ◽

pp. 607-613 ◽

Cited By ~ 2

Author(s):

Kevin D. Pang ◽

Charles C. Voge ◽

Jack W. Rhoads

Keyword(s):

Size Distribution ◽

Spherical Shape ◽

Mie Scattering ◽

Narrow Size Distribution ◽

Electrostatic Levitation ◽

Volcanic Origin ◽

Micron Diameter

Abstract.All observed optical and infrared properties of Saturn's E-ring can be explained in terms of Mie scattering by a narrow size distribution of ice spheres of 2 - 2.5 micron diameter. The spherical shape of the ring particles and their narrow size distribution imply a molten (possibly volcanic) origin on Enceladus. The E-ring consists of many layers, possibly stratified by electrostatic levitation.

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On the Shape of Field-Ion Emitters

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100092566 ◽

1976 ◽

Vol 34 ◽

pp. 520-521

Author(s):

H.C. Eaton ◽

B.N. Ranganathan ◽

T.W. Burwinkle ◽

R. J. Bayuzick ◽

J.J. Hren

Keyword(s):

Grain Boundary ◽

Spherical Shape ◽

Theoretical Strength ◽

Evaporation Process ◽

Field Evaporation ◽

Geometric Information ◽

Field Ion Microscopy ◽

Considerable Error ◽

True Shape ◽

Ion Microscopy

The shape of the emitter is of cardinal importance to field-ion microscopy. First, the field evaporation process itself is closely related to the initial tip shape. Secondly, the imaging stress, which is near the theoretical strength of the material and intrinsic to the imaging process, cannot be characterized without knowledge of the emitter shape. Finally, the problem of obtaining quantitative geometric information from the micrograph cannot be solved without knowing the shape. Previously published grain-boundary topographies were obtained employing an assumption of a spherical shape (1). The present investigation shows that the true shape deviates as much as 100 Å from sphericity and boundary reconstructions contain considerable error as a result.Our present procedures for obtaining tip shape may be summarized as follows. An empirical projection, D=f(θ), is obtained by digitizing the positions of poles on a field-ion micrograph.

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Investigation of ultra-thin films of YBa2Cu3O7−δ grown on MgO

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100173169 ◽

1990 ◽

Vol 48 (4) ◽

pp. 6-7

Author(s):

S.K. Streiffer ◽

C.B. Eom ◽

J.C. Bravman ◽

T.H. Geballet

Keyword(s):

Thin Films ◽

Room Temperature ◽

Deposition Process ◽

Nucleation And Growth ◽

Multilayer Structures ◽

Rf Power ◽

Oxygen Loss ◽

Transmission Electron ◽

Single Target ◽

Mtorr Argon

The study of very thin (<15 nm) YBa2Cu3O7−δ (YBCO) films is necessary both for investigating the nucleation and growth of films of this material and for achieving a better understanding of multilayer structures incorporating such thin YBCO regions. We have used transmission electron microscopy to examine ultra-thin films grown on MgO substrates by single-target, off-axis magnetron sputtering; details of the deposition process have been reported elsewhere. Briefly, polished MgO substrates were attached to a block placed at 90° to the sputtering target and heated to 650 °C. The sputtering was performed in 10 mtorr oxygen and 40 mtorr argon with an rf power of 125 watts. After deposition, the chamber was vented to 500 torr oxygen and allowed to cool to room temperature. Because of YBCO’s susceptibility to environmental degradation and oxygen loss, the technique of Xi, et al. was followed and a protective overlayer of amorphous YBCO was deposited on the just-grown films.

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