Fluctuations in aqueous methanol, ethanol, and propan-1-ol: amplitude and wavelength of fluctuation

1999 ◽  
Vol 77 (12) ◽  
pp. 2039-2045 ◽  
Author(s):  
Y Koga
Keyword(s):  
Isentropic Compressibility ◽  
Volume Effect ◽  
Mean Square ◽  
Aqueous Methanol ◽  
Mean Square Fluctuation ◽  
Volume Entropy ◽  
The Mean ◽  
Excess Partial Molar Enthalpy ◽  
Derivatives Of ◽  
Alcohol Alcohol

Density, heat capacity, and isentropic compressibility data for aqueous methanol, ethanol, and propan-1-ol by Benson's group were used to evaluate two kinds of fluctuations; mean-square fluctuation densities; and (mean-square) normalized fluctuations, respectively, in volume, entropy, and cross (entropy/volume) effect. The mean-square fluctuation densitiesprovide measures for the amplitude (intensity) of the fluctuation, while the normalized fluctuations contain information regarding the wavelength (extensity) of the fluctuation. Furthermore, their composition derivatives, the partial molar fluctuationsof alcohols were calculated. These quantities signify the effect of additional solute on the respective fluctuations. These data were interpreted in terms of mixing schemes learned earlier in this laboratory by using the data of excess partial molar enthalpy, entropy, and volume, and the respective alcohol-alcohol interaction functions, i.e., the composition derivatives of partial molar quantities. Key words: aqueous methanol, ethanol, and propan-1-ol;fluctuation density; normalized fluctuation; partial molar fluctuations of alcohol.

scholarly journals On fluctuations in electromagnetic radiation

1939 ◽  
Vol 170 (941) ◽  
pp. 252-265 ◽  
Keyword(s):  
Quantum Theory ◽  
Energy Density ◽  
Electromagnetic Radiation ◽  
Photoelectric Effect ◽  
Mean Square ◽  
Light Quanta ◽  
Mean Square Fluctuation ◽  
The Mean ◽  
General Thermodynamics

The question of fluctuations in electromagnetic radiation played an important part during the first period of the development of quantum theory. After having introduced (Einstein 1905) the conception of light quanta or photons in order to explain the observed phenomena of the photoelectric effect, Einstein (1909) considered the consequences of this idea for other properties of the radiation. Planck’s formula for the energy density of radiation implies, by arguments of general thermodynamics and statistics, the following expression for the mean square fluctuation of the energy contained in a volume v in terms of the mean energy Ē v .

scholarly journals A Model for Fuel Spray Formation with Atomizing Air

Fluids ◽  
2019 ◽  
Vol 4 (1) ◽  
pp. 20
Author(s):  
David J. Schmidt ◽  
William Kvasnak ◽  
Goodarz Ahmadi
Keyword(s):  
Swirling Flow ◽  
Shape Change ◽  
Fluid Velocity ◽  
Time Averaging ◽  
Mean Square ◽  
Spray Formation ◽  
Fuel Droplets ◽  
Mean Square Fluctuation ◽  
The Mean ◽  
Probability Density Function Pdf

The formation of a liquid spray emanating from a nozzle in the presence of atomizing air was studied using a computational model approach that accounted for the deformation and break up of droplets. Particular attention was given to the formation of sprays under non-swirling flow conditions. The instantaneous fluctuating fluid velocity and velocity gradient components were evaluated with the use of a probability density function (PDF)-based Langevin equation. Motions of atomized fuel droplets were analyzed, and ensemble and time averaging were used for evaluating the statistical properties of the spray. Effects of shape change of droplets, and their breakup, as well as evaporation, were included in the model. The simulation results showed that the mean-square fluctuation velocities of the droplets vary significantly with their size and shape. Furthermore, the mean-square fluctuation velocities of the evaporating droplet differed somewhat from non-evaporating droplets. Droplet turbulence diffusivities, however, were found to be close to the diffusivity of fluid point particles. The droplet velocity, concentration, and size of the simulated spray were compared with the experimental data and reasonable agreement was found.

scholarly journals Fluctuating Order Parameter in Doped Cuprate Superconductors

2003 ◽  
Vol 17 (18n20) ◽  
pp. 3607-3611 ◽  
Author(s):  
V. M. Loktev ◽  
Yu. G. Pogorelov ◽  
V. M. Turkowski
Keyword(s):  
Doping Level ◽  
Order Parameter ◽  
Cuprate Superconductors ◽  
Superconducting Order Parameter ◽  
Mean Square ◽  
Spatial Correlations ◽  
In Doping ◽  
Mean Square Fluctuation ◽  
The Mean ◽  
D Wave

We discuss the static fluctuations of the d-wave superconducting order parameter Δ in CuO 2 planes, due to quasiparticle scattering by charged dopants. The analysis of two-particle anomalous Green functions at T = 0 permits to estimate the mean-square fluctuation δ2 = <Δ2> - <Δ>2, averaged in random dopant configurations, to the lowest order in doping level c. Since Δ is found to saturate with growing doping level while δ remains to grow, this can explain the collapse of Tc at overdoping. Also we consider the spatial correlations <Δ(0)Δ(R)> for order parameter in different points of the plane.

Asymmetric X-ray line broadening of plastically deformed crystals. I. Theory

1988 ◽  
Vol 21 (1) ◽  
pp. 47-54 ◽  
Author(s):  
I. Groma ◽  
T. Ungár ◽  
M. Wilkens
Keyword(s):  
Dislocation Density ◽  
Mean Square ◽  
Line Profiles ◽  
Line Broadening ◽  
X Ray Diffraction ◽  
X Ray ◽  
Average Dislocation Density ◽  
Mean Square Fluctuation ◽  
The Mean ◽  
Dipole Polarization

X-ray diffraction line profiles of plastically deformed Cu single crystals orientated for ideal multiple slip were recently found to be markedly asymmetric. A theory is developed to interpret this kind of asymmetric line broadening in terms of the average dislocation density, the dipole polarization of the dislocation structure and the mean square fluctuation of the dislocation density.

CORRELATIONS OF PITCHES IN MUSIC

Fractals ◽  
1996 ◽  
Vol 04 (04) ◽  
pp. 547-553 ◽  
Author(s):  
YU SHI
Keyword(s):  
Power Spectrum ◽  
Long Range ◽  
Power Law ◽  
Piano Music ◽  
Fundamental Principle ◽  
Mean Square ◽  
Scaling Exponents ◽  
One Dimensional ◽  
Mean Square Fluctuation ◽  
The Mean

We investigate correlations among pitches in several songs and pieces of piano music. Real values of tones are mapped to positions within a one-dimensional walk. The structure of music, such as beat, measure and stanza, are reflected in the change of scaling exponents of the mean square fluctuation. Usually the pitches within one beat are nearly random, while nontrivial correlations are found within duration around a measure; for longer duration the mean square fluctuation is nearly flat, indicating exact 1/f power spectrum. Some interesting features are observed. Correlations are also studied by treating different tones as different symbols. This kind of correlation cannot reflect the structure of music, though long-range power-law is also discovered. Our results support the viewpoint that the fundamental principle of music is the balance between repetition and contrast.

The Bordeaux Automatic Meridian Circle

1978 ◽  
Vol 48 ◽  
pp. 227-228
Author(s):  
Y. Requième
Keyword(s):  
Mean Square Error ◽  
Mean Square ◽  
Meridian Circle ◽  
The Mean ◽  
Full Automation

In spite of important delays in the initial planning, the full automation of the Bordeaux meridian circle is progressing well and will be ready for regular observations by the middle of the next year. It is expected that the mean square error for one observation will be about ±0.”10 in the two coordinates for declinations up to 87°.

The mean-square generalized delayed decision feedback sequence detector

2003 ◽  
Vol 14 (3) ◽  
pp. 265-268 ◽  
Author(s):  
Maurizio Magarini ◽  
Arnaldo Spalvieri ◽  
Guido Tartara
Keyword(s):  
Decision Feedback ◽  
Mean Square ◽  
The Mean

Limit tolerances for sums of measurement errors

2018 ◽  
Vol 934 (4) ◽  
pp. 59-62
Author(s):  
V.I. Salnikov
Keyword(s):  
Normal Distribution ◽  
Mean Square Error ◽  
Gaussian Distribution ◽  
Measurement Errors ◽  
Theory And Practice ◽  
Mean Square ◽  
The Mean ◽  
Limiting Values ◽  
Limiting Value

The question of calculating the limiting values of residuals in geodesic constructions is considered in the case when the limiting value for measurement errors is assumed equal to 3m, ie ∆рred = 3m, where m is the mean square error of the measurement. Larger errors are rejected. At present, the limiting value for the residual is calculated by the formula 3m√n, where n is the number of measurements. The article draws attention to two contradictions between theory and practice arising from the use of this formula. First, the formula is derived from the classical law of the normal Gaussian distribution, and it is applied to the truncated law of the normal distribution. And, secondly, as shown in [1], when ∆рred = 2m, the sums of errors naturally take the value equal to ?pred, after which the number of errors in the sum starts anew. This article establishes its validity for ∆рred = 3m. A table of comparative values of the tolerances valid and recommended for more stringent ones is given. The article gives a graph of applied and recommended tolerances for ∆рred = 3m.

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