scholarly journals Theory of Holographic Formation in Multicomponent Photopolymer-Based Nanocomposites-=SUP=-*-=/SUP=-

2020 ◽  
Vol 128 (8) ◽  
pp. 1201
Author(s):  
V.N. Borisov ◽  
V.V. Lesnichii
Keyword(s):  
Volume Fraction ◽  
Effective Diffusion ◽  
Multicomponent Diffusion ◽  
Spatial Spectrum ◽  
Relative Volume ◽  
Neutral Component ◽  
Relative Volume Fraction ◽  
Polymer Component ◽  
Good Guide ◽  
Modified Theory

The derivation of the three-component (monomer, chemically neutral component, and polymer) photopolymerization model from general thermodynamic considerations is presented. This model, together with another previously published one, are subject to a numerical solution for the case of a two-component one-dimensional diffusion (polymer component being steady). The divergence of results of work for both models was compared based on the average speed of the root-mean-square deviation in the spatial spectrum domain for relative volume fraction functions for all three components. Such a comparison was performed for 81 pairs of initial relative amount of neutral component and effective diffusion coefficient. The results of the work may serve as a good guide for the choice of parameters of experiments, which are aimed to verify the correctness of the modified theory. Keywords: photopolymerization, photoformer, holographic grating, multicomponent diffusion, polymer, holography.

scholarly journals Thermoplasmonic of Single Au@SiO2 and SiO2@Au Core Shell Nanoparticles in Deionized Water and Poly-vinylpyrrolidoneMatrix

2019 ◽  
Vol 16 (2) ◽  
pp. 0376 ◽  
Author(s):  
Gatea Et al.
Keyword(s):  
Light Propagation ◽  
Volume Fraction ◽  
Relative Volume ◽  
Core Shell ◽  
Distribution Profile ◽  
Shell Nanoparticles ◽  
Thermal Generation ◽  
Relative Volume Fraction ◽  
Core Shell Nanoparticles ◽  
532 Nm

Metal nanoparticles can serve as an efficient nano-heat source with confinement photothermal effects. Thermo-plasmonic technology allows researchers to control the temperature at a nanoscale due to the possibility of precise light propagation. The response of opto-thermal generation of single gold-silica core-shell nanoparticle immersed in water and Poly-vinylpyrrolidone surrounding media is theoretically investigated. Two lasers (CW and fs pulses) at the plasmonic resonance (532 nm) are utilized. For this purpose, finite element method is used via COMSOL multiphysics to find a numerical computation of absorption cross section for the proposed core –shell NP in different media. Thermo-plasmonic response for both lasers is studied. The heat profile of different nanostructures is estimated. The results revealed that the temperature distribution profile was varied due to changing in the relative volume fraction between the core and the shell of nanoparticle.

UV-induced vesicle to micelle transition: a mechanistic study

2019 ◽  
Vol 10 (44) ◽  
pp. 6037-6046 ◽  
Author(s):  
Craig A. Machado ◽  
Roger Tran ◽  
Taylor A. Jenkins ◽  
Amanda M. Pritzlaff ◽  
Michael B. Sims ◽  
...  
Keyword(s):  
Block Copolymer ◽  
Volume Fraction ◽  
Relative Volume ◽  
Mechanistic Study ◽  
Relative Volume Fraction ◽  
Self Assembled

The morphology of self-assembled block copolymer aggregates is highly dependent on the relative volume fraction of the hydrophobic block.

Degree of Mixing Analyses of Concentrated Suspensions by Electron Probe and X-Ray Diffraction

1993 ◽  
Vol 66 (4) ◽  
pp. 527-537 ◽  
Author(s):  
R. Yazici ◽  
D. M. Kalyon
Keyword(s):  
Electron Probe ◽  
Volume Fraction ◽  
Relative Volume ◽  
Mixing Efficiency ◽  
Energy Dispersive Analysis ◽  
X Ray Diffraction ◽  
Concentrated Suspensions ◽  
Relative Volume Fraction ◽  
X Ray ◽  
Definition Of

Abstract Two x-ray based techniques involving energy-dispersive analysis and diffractometry were introduced to the analyses of the degree of mixedness, i.e. the “goodness of mixing” of concentrated suspensions. A hydroxyl terminated polybutadene matrix was mixed with aluminum and ammonium sulfate. In the analysis, the ratio of the relative volume fractions of the two solid components was used as the basis of the analytical evaluation. Both characterization techniques are capable of determining the relative volume fraction of the two solid components as a representative measurement of the distributive mixing efficiency and both are sensitive to the scale of examination. The introduced techniques should be useful in the better definition of the degree of mixedness as well as in resolving differences in mixing efficiencies of various mixers used in processing of concentrated suspensions.

Dynamics of Multilayered Composite Plates With Shape Memory Alloy Wires

2003 ◽  
Vol 70 (3) ◽  
pp. 313-327 ◽  
Author(s):  
A. J. Zak ◽  
M. P. Cartmell ◽  
W. Ostachowicz
Keyword(s):  
Finite Element ◽  
Shape Memory ◽  
Volume Fraction ◽  
Composite Plates ◽  
Relative Volume ◽  
The Finite Element Method ◽  
Relative Volume Fraction ◽  
Multilayered Composite ◽  
Reinforcing Fibers ◽  
Tuning Methods

In this paper certain aspects of the dynamic behavior of a multilayered, composite plate with shape memory alloys (SMA) wires have been investigated. The influence of parameters such as the orientation and location of SMA wires, the orientation and relative volume fraction of reinforcing fibers, the thickness-to-length and length-to-width ratios, and different boundary conditions, on changes in the critical load, the natural frequencies and the modes of vibrations of the plate have all been studied and discussed in the paper. The use of two different techniques, generally known in the literature as the active property tuning and active strain energy tuning methods, has also been investigated. The results presented in this paper have been obtained by the use of the finite element method and a new finite element formulated for multilayered composite plates has been applied for this purpose.

scholarly journals EFFECTIVENESS OF USE OF NANO FILLERS OF DIFFERENT TYPES IN POLYMERIC COMPOSITES

2020 ◽  
Vol 63 (4) ◽  
pp. 81-85
Author(s):  
Vladimir Z. Aloyev ◽  
Zaira M. Zhirikova ◽  
Memunat A. Tarchokova
Keyword(s):  
Fractal Dimension ◽  
Polymer Nanocomposites ◽  
Maximum Degree ◽  
Volume Fraction ◽  
Relative Proportion ◽  
Relative Volume ◽  
Theoretical Evaluation ◽  
Relative Volume Fraction ◽  
Different Types ◽  
Degree Of Filling

The paper provides a theoretical analysis of the effectiveness of using different types of nanofillers to produce high-strength polymer composites. Three basic types of nanoscale inorganic nanofillers were selected: dispersed nanoparticles (0D-nanofillers), carbon nanotubes and nanofibers (1D-nanofillers), and organoclay, graphene, etc. (2D-fillers). The relative modulus of elasticity, i.e. the degree of amplification, is used as the main criterion for the effectiveness of nanofillers. Within the framework of the percolation model, the amplification levels of nanocomposites for different types of nanofillers are determined depending on the relative volume fraction of nanofillers and interfacial regions. It is shown that interfacial regions in polymer nanocomposites are treated as a reinforcing element of the nanocomposite structure. To describe the surface structure of nanofiller particles, an effective value of the fractal dimension is used, which serves as a determining factor for the relative proportion of interfacial regions. At a condition that the fractal dimension of the structural framework of nanofiller particles cannot exceed the fractal dimension of the enclosing Euclidean space, the relative proportion of interfacial regions and, through it, the maximum degree of filling for the types of nanofillers under consideration are determined. The results of the theoretical evaluation of the maximum limit value of the fractal dimension of nanofiller particles carried out in this work show that the formation of a bulk frame of particles is possible only for anisotropic nanofillers, and dispersed particles form chains that do not change the structure of the polymer matrix in comparison with the matrix polymer. It is also found that for each type of nanofiller, there is a limit maximum degree of filling, which ultimately determines the limit maximum degree of amplification of the nanocomposite. These results allow us to conclude that the most effective for creating structural polymer nanocomposites is a dispersed nanofiller.

EVALUATION OF RELATIVE VOLUME FRACTION OF TETRAGONAL PHASE AND RHOMBOHEDRAL PHASE IN Pb(Zr,Ti)O3 FILM BY RAMAN SPECTROSCOPY

2010 ◽  
Vol 112 (1) ◽  
pp. 33-41 ◽  
Author(s):  
MASAMICHI NISHIDE ◽  
HIROSHIGE TAKEUCHI ◽  
TAKESHI TAI ◽  
TAKASHI KATODA ◽  
SHINTARO YOKOYAMA ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Tetragonal Phase ◽  
Volume Fraction ◽  
Rhombohedral Phase ◽  
Relative Volume ◽  
Relative Volume Fraction

scholarly journals Influence of Polymer Modification on the Microstructure of Shielding Concrete

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 498 ◽  
Author(s):  
Kamil Zalegowski ◽  
Tomasz Piotrowski ◽  
Andrzej Garbacz
Keyword(s):  
Compressive Strength ◽  
Volume Fraction ◽  
Voronoi Tessellation ◽  
Relative Volume ◽  
Polymer Modification ◽  
Relative Volume Fraction ◽  
Shielding Properties ◽  
Student’S T ◽  
Polymer Dispersions ◽  
The Impact

In this paper an analysis of the influence of polymer modification on the microstructure, shielding properties against neutrons, and compressive strength of heavy-weight magnetite concrete is carried out. The modifications involve the addition of acrylic or epoxy dispersions as well as micro- or/and macrofibers. A computer image analysis method is used to evaluate the microstructure of concretes and parameters of pore structure are calculated; these parameters include relative volume fraction, relative specific surface area, and pore arrangement ratios, including a proprietary ratio based on Voronoi tessellation. An assessment of significance of differences between stereological parameters of reference concrete and polymer modified concretes, as well as the impact of polymer form (dispersion or fibers) on shielding properties and compressive strength is carried out using Student’s t-test. The results show that except for the effect of the addition of both polypropylene micro- and macrofibers on the relative volume of pores, all other modifications result in statistically significant changes in the values of stereological parameters. Nevertheless, it is shown that neither polymer dispersions nor fibers have a statistically significant impact on shielding properties, but that they do influence compressive strength.

Effect of nano BiPb-2212 phase addition on BiPb-2223 phase properties

2018 ◽  
Vol 32 (16) ◽  
pp. 1850178 ◽  
Author(s):  
N. H. Mohammed ◽  
A. I. Abou-Aly ◽  
M. ME. Barakat ◽  
M. S. Hassan
Keyword(s):  
Electron Microscope ◽  
Volume Fraction ◽  
Interlayer Coupling ◽  
Xrd Analysis ◽  
Solid State Reaction Method ◽  
Relative Volume ◽  
Fermi Velocity ◽  
Superconducting Transition ◽  
Relative Volume Fraction ◽  
Transmission Electron

BiPb-2212 phase in nanoscale was added to BiPb-2223 phase with a general stoichiometry of (Bi[Formula: see text]Pb[Formula: see text]Sr[Formula: see text]Ca[Formula: see text]Cu[Formula: see text]O[Formula: see text]/Bi[Formula: see text]Pb[Formula: see text]Sr[Formula: see text]Ca[Formula: see text]Cu[Formula: see text]O[Formula: see text], 0.0 [Formula: see text] x [Formula: see text] 2.5 wt.%. All samples were prepared by the standard solid-state reaction method. The prepared nano BiPb-2212 phase was characterized by X-ray powder diffraction (XRD) and transmission electron microscope (TEM). The prepared samples were characterized by XRD and the scanning electron microscope (SEM). XRD analysis indicated that the sample with x = 1.5 wt.% has the highest relative volume fraction for BiPb-2223 phase. Samples were examined by electrical resistivity and I–V measurements. There is no significant change in the superconducting transition temperature [Formula: see text] for all samples. The highest critical current density [Formula: see text] was recorded for the sample with x = 1.5 wt.%. The normalized excess conductivity [Formula: see text] was calculated according to Aslamazov–Larkin (AL) model. Four different fluctuating regions were recorded as the temperature decreased. The coherence length along the c-axis at 0 K [Formula: see text], interlayer coupling strength s, Fermi velocity [Formula: see text] of the carriers and Fermi energy [Formula: see text] were calculated for both samples with x = 0.0 wt.% and 1.5 wt.%.

scholarly journals Nanostructural, Chemical, and Mechanical Features of nc-Si:H Films Prepared by PECVD

2012 ◽  
Vol 2012 ◽  
pp. 1-8
Author(s):  
Jong-Ick Son ◽  
Hee-Jong Nam ◽  
Nam-Hee Cho
Keyword(s):  
Film Thickness ◽  
Vapor Deposition ◽  
Deposition Time ◽  
Volume Fraction ◽  
Chemical Vapor ◽  
Relative Volume ◽  
Relative Volume Fraction ◽  
The Mean ◽  
Si Films ◽  
Si Nanocrystallites

This study examined the effects of film thickness on the nanostructural, chemical, and mechanical features of nc-Si:H films deposited by plasma-enhanced chemical vapor deposition. SiH4and H2were used as the source gases, and the deposition time was varied from 10 to 360 min. The mean nanocrystallites size in the Si films increased from~6 to~8 nm with increasing film thickness from 85 to 4150 nm. Moreover, the nanocrystallite concentration and elastic modulus increased from~7.5 to~45% and from 135 to 147 Gpa, respectively. In the 4150 nm thick film, the relative volume fraction of Si nanocrystallites and relative fraction of Si–H bonds in the films were approximately~45% and~74.5%, respectively.

Synthesis of porosity controlled ceramic membranes

1991 ◽  
Vol 6 (5) ◽  
pp. 1073-1081 ◽  
Author(s):  
Qunyin Xu ◽  
Marc A. Anderson
Keyword(s):  
Pore Radius ◽  
Volume Fraction ◽  
Sol Gel ◽  
Ceramic Membranes ◽  
Relative Volume ◽  
Particle Packing ◽  
Relative Volume Fraction ◽  
Charged System ◽  
Gel Processing ◽  
Aggregate Structures

Porosity control in ceramic membranes has been achieved by controlling particle packing densities in sol-gel processing. TiO2 xerogels with two mean pore radii of 0.7 and 1.7 nm and a porosity varying from 30% to 52% have been obtained. ZrO2 xerogels with a mean pore radius of 0.7 nm and a porosity varying from 7% to 34% have also been prepared. The principle of controlling porosity is to make spongy aggregates and to control the degree of aggregation. Experiments have been conducted to show that spongy aggregates can be produced by gradually removing protons from the strongly charged particles. Viscosity techniques have been used to measure the relative volume fraction of the dispersed phase which, in turn, provides information on aggregate structures. Two aggregation models have been proposed to explain different structural aggregates formed through thermal destabilization in the highly charged system and through charge neutralization by gradually removing charge from the particles in the system.

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