Dehydration of Fractal Particles of Iron (III) and Aluminum Hydroxides

1995 ◽  
Vol 407 ◽  
Author(s):  
A. A. Vertegel ◽  
S. V. Kalinin ◽  
N. N. Oleynikov ◽  
Yu. D. Tretyakov
Keyword(s):  
Experimental Data ◽  
Fractal Dimension ◽  
Metal Atom ◽  
Quantitative Model ◽  
Kinetic Behavior ◽  
Dehydration Rate ◽  
Aluminum Hydroxides ◽  
Theoretical Predictions ◽  
Fractal Particles ◽  
Good Agreement

ABSTRACTThe kinetic behavior of Fe(OH)3 and AI(OH)3 powders during thermal dehydration is investigated. It has been shown that the dehydration rate is governed by the value of fractal dimension of the sample without any respect to the nature of metal atom in hydroxide. The quantitative model for dehydration of fractal particles with particular value of fractal dimension is suggested. Theoretical predictions are in a good agreement with experimental data.

Wilberforce pendulum: modelling linearly damped coupled oscillations of a spring-mass system

2021 ◽  
Author(s):  
Robert Frederik Diaz Uy ◽  
Chenghao Yuan ◽  
Zhengshan Chai ◽  
Justin Khor
Keyword(s):  
Experimental Data ◽  
Angular Displacement ◽  
Beat Frequency ◽  
Vertical Displacement ◽  
Quantitative Model ◽  
Moment Of Inertia ◽  
Lagrangian Formalism ◽  
Mass System ◽  
Coupled Oscillations ◽  
Theoretical Predictions

Abstract The Wilberforce pendulum is a coupled spring-mass system, where a mass with adjustable moment of inertia is suspended from a helical spring. Energy is converted between the translational and torsional modes, and this energy conversion is most clearly observed at resonance, which occurs when the damped natural frequencies of the two oscillation modes are equal. A theoretical model—with energy losses due to viscous damping accounted for—was formulated using the Lagrangian formalism to predict the pendulum mass’ trajectory. Theoretical predictions were compared with experimental data, showing good agreement. Fourier analysis of both theoretical predictions and experimental data further corroborate the validity of our quantitative model. The dependence of oscillation features like beat frequency and maximum conversion amplitude on relevant parameters such as the initial vertical displacement, initial angular displacement and moment of inertia was also investigated and experimentally verified.

scholarly journals New test of the dynamic theory of neutron diffraction by a moving grating

2018 ◽  
Vol 177 ◽  
pp. 03005
Author(s):  
Maxim Zakharov ◽  
Alexander Frank ◽  
German Kulin ◽  
Semyon Goryunov
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Neutron Diffraction ◽  
Dynamic Theory ◽  
Time Of Flight ◽  
Dynamical Theory ◽  
Zero Order ◽  
Significant Suppression ◽  
Theoretical Predictions ◽  
Good Agreement

Recently, multiwave dynamical theory of neutron diffraction by a moving grating was developed. The theory predicts that at a certain height of the grating profile a significant suppression of the zero-order diffraction may occur. The experiment to confirm predictions of this theory was performed. The resulting diffracted UCNs spectra were measured using time-of-flight Fourier diffractometer. The experimental data were compared with the results of numerical simulation and were found in a good agreement with theoretical predictions.

A Quantitative Model of Surface Segregation in III-V Ternary Compounds

2000 ◽  
Vol 618 ◽  
Author(s):  
Sergey Yu. Karpov ◽  
Yuri N. Makarov
Keyword(s):  
Surface Segregation ◽  
Quantitative Model ◽  
Model Verification ◽  
Key Factors ◽  
Underlying Assumption ◽  
Factors Affecting ◽  
Surface Population ◽  
Theoretical Predictions ◽  
Good Agreement ◽  
Crystal Bulk

ABSTRACTA quantitative model of surface segregation free from adjustable parameters is suggested for the growth of ternary III-V compounds. In contrast to previous approaches, the model considers the dynamics of surface population by the three elements producing the ternary alloy. The underlying assumption is that the atoms in the adsorption layer are in equilibrium with the crystal bulk. Elastic strain arising in the epitaxial layer due to the lattice constant mismatch with the substrate is found to be one of the key factors affecting segregation. Along with growth temperature, it controls the segregation efficiency and the composition profile evolution in a growing heterostructure. The effect of the V/III ratio, growth rate and other parameters is accounted for. Here, we apply the model to analyze the InGaAs growth by molecular beam epitaxy owing to the vast experimental data available for the model verification. The theoretical predictions show a good agreement with the experimental observations

Thermal Behavior and Friction in Journal Bearings

1970 ◽  
Vol 92 (3) ◽  
pp. 373-380 ◽  
Author(s):  
Al. Nica
Keyword(s):  
Experimental Data ◽  
Thermal Behavior ◽  
Heat Dissipation ◽  
Journal Bearings ◽  
Friction Torque ◽  
Operating Characteristics ◽  
Lubricant Flow ◽  
Theoretical Predictions ◽  
Theoretical Results ◽  
Good Agreement

This paper deals with friction and the field of temperature in the lubricant film of journal bearings. Theoretical results regarding the thermal behavior are checked with experimental data and good agreement is found. Emphasis is put on the variation of temperature and lubricant flow with the operating characteristics of the bearing and it is seen that theoretical predictions for minima of friction torque are backed by temperature measurements. Further on, the friction torque and the mechanism of heat dissipation in bearings are dealt with, in order to verify the assumptions used in the calculation schemes. The means of efficiently cooling the bearing are also discussed, as well as the part played by the divergent zone in this process.

MODELING OF GOLD DISPERSION IN GLASSY POLYMERS BY SMOLUCHOWSKI EQUATION

2002 ◽  
Vol 13 (09) ◽  
pp. 1301-1312 ◽  
Author(s):  
ZBIGNIEW J. GRZYWNA ◽  
JACEK STOLARCZYK
Keyword(s):  
Differential Equation ◽  
Experimental Data ◽  
Partial Differential Equation ◽  
Smoluchowski Equation ◽  
Glassy Polymers ◽  
Time Dependent ◽  
Acetone Vapor ◽  
Induced Stress ◽  
Theoretical Predictions ◽  
Good Agreement

A unidimensional diffusion in a potential field of induced stress is considered. The way from random walk (RW) to limiting partial differential equation (Smoluchowski equation) for standard and time dependent RW is shown. A technologically important case of gold dispersion in crystallizing polymer swollen by acetone vapor is analyzed. Theoretical predictions based on Smoluchowski equation with time dependent coefficients are found to be in very good agreement with experimental data.

The bursting of a charged cylindrical film

1972 ◽  
Vol 328 (1575) ◽  
pp. 529-539 ◽  
Keyword(s):  
Experimental Data ◽  
Finite Length ◽  
Experimental Results ◽  
Exact Calculation ◽  
Conducting Film ◽  
Half Wavelength ◽  
Theoretical Predictions ◽  
Long Cylinder ◽  
Good Agreement

This paper is a sequel to Sir Geoffrey Taylor’s study of the bursting of an electrified cylindrical conducting film. Taylor described experiments in which the voltages, at which the film becomes statically unstable, were observed for various lengths of film. These results were compared with the theoretical predictions for disturbances on an infinitely long cylinder having a wavelength equal to the length of film used. It is shown here that a transition in the mode of bursting from an axisymmetric whole wavelength mode to a lateral half wavelength mode is to be expected and that the experimental data conform with this transition. An exact calculation of the modes for a film of finite length is also given here and the resulting theoretical predictions of instability and bursting voltages are in very good agreement with the experimental results.

Kinetic Model of Thermoelastic Martensite Transformation in Niti and NiMn Based Shape Memory Alloys

1995 ◽  
Vol 398 ◽  
Author(s):  
K. H. Wu ◽  
J.D. Shi ◽  
F. Yang ◽  
Z. J. Pu
Keyword(s):  
Experimental Data ◽  
Shape Memory Alloys ◽  
Shape Memory ◽  
Martensite Transformation ◽  
Quantitative Model ◽  
Proposed Model ◽  
Series Of Experiments ◽  
The Relationship ◽  
Kinetics Of ◽  
Good Agreement

ABSTRACTA new, quantitative model was developed to describe the martensite transformation kinetics of thermoelastic shape memory alloys (SMAs). In addition, a series of experiments were conducted to study the Kinetics of thermoelastic martensite transformation in four SMA systems: NiTi, NiTi-15at%Hf, NiTi-20at%Zr and NiMn-7.5at%Ti alloys. Comparisons between data of the kinetic of martensite transformation with the present theoretic models show that the proposed model is in good agreement and concurs with the experimental data. Also, a comparison of data from the proposed model with data from existing kinetic models, such as Liang's and Magee's [1,7], indicates that the proposed model can better describe the experimental data, including the relationship between dξ(T)/dT and ξ, and dξ(T)/dT and T.

Reaction mechanism of the 16O + d reactions

1970 ◽  
Vol 48 (19) ◽  
pp. 2235-2253 ◽  
Author(s):  
N. E. Davison ◽  
W. K. Dawson ◽  
G. Roy ◽  
W. J. McDonald
Keyword(s):  
Experimental Data ◽  
Compound Nucleus ◽  
Cross Sections ◽  
Direct Interaction ◽  
Scattering Data ◽  
Orbit Potential ◽  
Spectroscopic Factors ◽  
Theoretical Predictions ◽  
Using Data ◽  
Good Agreement

The reactions 16O(d,d)16O, 16O(d,p)17O, and 16O(d,n)17F have been studied in the deuteron energy range 4.00–6.00 MeV in order to determine to what extent current theories can satisfactorily describe these reactions. It was found that the theoretical curves from both the optical and DWBA models fit the experimental data significantly better when the deuteron optical-model potentials had been obtained using a spin–orbit potential in the analysis of the elastic scattering data. Spectroscopic factors obtained for the ground and first-excited states of 17O and 17F using the DWBA theory are in satisfactory agreement with theoretical predictions and with values obtained by previous workers. Small, but nonzero, spectroscopic factors have been obtained for the states at 3.058 and 3.846 MeV excitation in 17O using data measured in this work and in previous experiments. The sum of the calculated direct interaction and compound-nucleus cross sections is in good agreement with experimental data for all states studied, whether they were populated primarily by direct or compound-nucleus reactions. The calculated compound-nucleus lifetimes are also in agreement with values obtained from an analysis of the fluctuations in the yield curves.

scholarly journals On ZRP wind input term consistency in Hasselmann equation

2016 ◽  
Author(s):  
Vladimir Zakharov ◽  
Donald Resio ◽  
Andrei Pushkarev
Keyword(s):  
Experimental Data ◽  
Time Domain ◽  
Source Term ◽  
Similarity Analysis ◽  
Self Similarity ◽  
The World ◽  
Theoretical Predictions ◽  
Input Source ◽  
Wind Input ◽  
Good Agreement

Abstract. The new ZRP wind input source term (Zakharov et al., 2012) is checked for its consistency via numerical simulation of Hasselmann equation. The results are compared to field experimental data, collected at different sites around the world, and theoretical predictions of self-similarity analysis. Good agreement is obtained for limited fetch and time domain statements.

Comparison Between Theoretical Predictions of Wave Resistance and Experimental Data for the Wigley Hull

1983 ◽  
Vol 27 (04) ◽  
pp. 215-226
Author(s):  
C. Y. Chen ◽  
F. Noblesse
Keyword(s):  
Experimental Data ◽  
Froude Number ◽  
Resistance Coefficient ◽  
Wave Resistance ◽  
Number Range ◽  
Theoretical Predictions ◽  
Wigley Hull ◽  
Sinkage And Trim ◽  
Theoretical Results ◽  
Good Agreement

A number of theoretical predictions of the wave-resistance coefficient of the Wigley hull are compared with one another and with available experimental data, to which corrections for sinkage and trim are applied. The averages of eleven sets of experimental data (corrected for sinkage and trim) and of eleven sets of theoretical results for large values of the Froude number, specifically for F 0.266, 0.313, 0.350, 0.402, 0.452, and 0.482, are found to be in fairly good agreement, in spite of considerable scatter in both the experimental data and the numerical results. Furthermore, several sets of theoretical results are fairly close to the average experimental data and the average theoretical predictions for these large values of the Froude number. Discrepancies between theoretical predictions and experimental measurements for small values of the Froude number, specifically for F = 0.18, 0.20, 0.22, 0.24, and 0.266, generally are much larger than for the above-defined high-Froude-number range. However, a notable exception to this general finding is provided by the first-order slender-ship approximation evaluated in Chen and Noblesse [1],3 which is in fairly good agreement with the average experimental data over the entire range of values of Froude number considered in this study.

Sign in / Sign up

Export Citation Format

Share Document