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The density

Their boiling points increase with the number of carbon atoms. For molecules of low carbon numbers, the addition of a carbon increases the boiling point about 25°C. Further additions result in a smaller increase. The density increases with the molecular weight 0.626 kg/1 for pentane which has 5 atoms of carbon, 0.791 kg/1 for pentacosane which has 25 carbon atoms, but the density is always much lower than 1. [Pg.3]

Eleven different groups of crude oils haye been defined according to the densities of their heavy gasoline cuts (100-200°C) and their residues with boiling points above 350°C as shown in Table 3.1. [Pg.40]

The standard specific gravity is the ratio of the density of a hydrocarbon at 15.55°C (60°F) to that of water at the same temperature. It differs from the specific gravity d] which is the ratio of the density of a hydrocarbon at 15°C to that of water at 4°C. [Pg.94]

The kinematic viscosity is defined as the ratio between the absolute viscosity and the density. It is expressed in m /s. The most commonly used unit is mm /s formerly called centistoke, cSt. [Pg.95]

In the first type of method, the density at saturation pressure is calculated, then this density is corrected for pressure. The COSTALD and Rackett methods belong to this category. Correction for pressure is done using Thompson s method. These methods are applicable only if the reduced temperature is less than 0.98. [Pg.114]

The density at saturation pressure is expressed as a function of reduced temperature ... [Pg.116]

The COSTALD (Corresponding states liquid density) method was originally developed for calculating the densities of liquefied gases its use has become generally widespread. [Pg.117]

The density of a liquid depends on the pressure this effect is particularly sensitive for light liquids at reduced temperatures greater than 0.8. For pressures higher than saturation pressure, the density is calculated by the relation published by Thompson et al. in 1979 ... [Pg.118]

When the liquid compressibility, Zj, has been obtained, the density is calculated as follows ... [Pg.120]

They can also be calculated from tbe kinematic viscosities at 100 and 210°F. After having calculated the densities, pj and p, one obtains ( S )... [Pg.128]

The surface tension is calculated starting from the parachor and the densities of the phases in equilibrium by the Sugden method (1924) J... [Pg.166]

The density and the volatility, expressed by the distillation curve and the vapor pressure, constitute the most important physical characteristics of motor fuels for obtaining satisfactory operation of a vehicle in all circumstances. [Pg.187]

The density varies with the temperature according to the relationship ... [Pg.187]

In practice, the user prefers the densest possible motor fuel that is compatible with the specifications, for it gives him the best volume NHV and highest fuel economy. It is estimated that an increase in density of 4 to 5% brings a reduction in consumption of 3 to 5%. Finally for the refiner, a margin of 50 thousandths accorded for the density of each type of gasoline, makes an acceptable compromise, while a tightening of the specification would be too constraining. [Pg.188]

The density, distillation curve, viscosity, and behavior at low temperature make up the essential characteristics of diesei fuel necessary for satisfactory operation of the engine. [Pg.213]

For optimum combustion, the fuel should vaporize rapidly and mix intimately with the air. Even though the design of the injection system and combustion chamber play a very important role, properties such as volatility, surface tension, and fuel viscosity also affect the quality of atomization and penetration of the fuel. These considerations justify setting specifications for the density (between 0.775 and 0.840 kg/1), the distillation curve (greater than 10% distilled at 204°C, end point less than 288°C) and the kinematic viscosity (less than 8 mm /s at -20°C). [Pg.226]

Commercial butane comprises mainly C4 hydrocarbons, with propane and propylene content being less than 19 volume %. The density should be equal to or greater than 0.559 kg/1 at 15°C (0.513 kg/1 at 50°C). The maximum vapor pressure should be 6.9 bar at 50°C and the end point less than or equal to 1°C. [Pg.232]

The density of heavy fuels is greater than 0.920 kg/1 at 15°C. The marine diesel consumers focus close attention on the fuel density because of having to centrifuge water out of the fuel. Beyond 0.991 kg/1, the density difference between the two phases —aqueous and hydrocarbon— becomes too small for correct operation of conventional centrifuges technical improvements are possible but costly. In extreme cases of fuels being too heavy, it is possible to rely on water-fuel emulsions, which can have some advantages of better atomization in the injection nozzle and a reduction of pollutant emissions such as smoke and nitrogen oxides. [Pg.236]

It is possible to modify the quality of the coke by calcination at high temperatures (1200-1400°C) this has the effect of reducing the volatile material and to increase the density. [Pg.292]

Under standard conditions of temperature and pressure (STP), the first four members of the alkane series (methane, ethane, propane, and butane) are gases. As length of the carbon increases the density of the compound increases (pentane) to C yHgg are liquids, and from C.,gH3g, the compounds exist as wax-like solids at STP. [Pg.90]

Phase behaviour describes the phase or phases in which a mass of fluid exists at given conditions of pressure, volume (the inverse of the density) and temperature (PVT). The simplest way to start to understand this relationship is by considering a single component, say water, and looking at just two of the variables, say pressure and temperature. [Pg.97]

Now using a hydrocarbon component, say ethane, as an example, let us consider the other parameter, volume, using a plot of pressure versus specific volume (i.e. volume per unit mass of the component, the inverse of the density). The process to be described could be performed physically by placing the liquid sample into a closed cell (PVT cell), and then reducing the pressure of the sample by withdrawing the piston of the cell and increasing the volume contained by the sample. [Pg.98]

Measured in MJ/m or Btu/ft, the Wobbe Index has an advantage over the calorific value of a gas (the heating value per unit volume or weight), which varies with the density of the gas. The Wobbe Index Is commonly specified in gas contracts as a guarantee of product quality. A customer usually requires a product whose Wobbe Index lies within a narrow range, since a burner will need adjustment to a different fuel air ratio if the fuel quality varies significantly. A sudden increase in heating value of the feed can cause a flame-out. [Pg.108]

The same definition of viscosity applies to oil as gas (see Section 5.2.6), but sometimes the kinematic viscosity is quoted. This is the viscosity divided by the density (u = i7p), and has a straight line relationship with temperature. [Pg.109]

The density of the oil at reservoir conditions is useful in calculating the gradient of oil and constructing a pressure - depth relationship in the reservoir (see section 5.2.8). [Pg.110]

In Section 5.2.8 we shall look at pressure-depth relationships, and will see that the relationship is a linear function of the density of the fluid. Since water is the one fluid which is always associated with a petroleum reservoir, an understanding of what controls formation water density is required. Additionally, reservoir engineers need to know the fluid properties of the formation water to predict its expansion and movement, which can contribute significantly to the drive mechanism in a reservoir, especially if the volume of water surrounding the hydrocarbon accumulation is large. [Pg.115]

Flence it can be seen that from the density of a fluid, the pressure gradient may be caloulated. Furthermore, the densities of water, oil and gas are so significantly different, that they will show quite different gradients on a pressure-depth plot. [Pg.117]

Finally, it is worth remembering the sequence of events which occur during hydrocarbon accumulation. Initially, the pores in the structure are filled with water. As oil migrates into the structure, it displaces water downwards, and starts with the larger pore throats where lower pressures are required to curve the oil-water interface sufficiently for oil to enter the pore throats. As the process of accumulation continues the pressure difference between the oil and water phases increases above the free water level because of the density difference between the two fluids. As this happens the narrower pore throats begin to fill with oil and the smallest pore throats are the last to be filled. [Pg.124]


See other pages where The density is mentioned: [Pg.71]    [Pg.175]    [Pg.211]    [Pg.239]    [Pg.241]    [Pg.245]    [Pg.247]    [Pg.296]    [Pg.333]    [Pg.109]    [Pg.116]    [Pg.117]    [Pg.181]    [Pg.182]    [Pg.184]    [Pg.187]    [Pg.188]    [Pg.213]    [Pg.237]    [Pg.240]    [Pg.98]    [Pg.116]    [Pg.145]   
See also in sourсe #XX -- [ Pg.74 ]




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An approximate equation for the singlet density

Analysis of the Electron Density Distribution

Anisotropy of the current-induced density

Avoiding the Diagonalization Step—Density Matrix-Based SCF

Bands and the Density of States

Behaviour of the quark number densities as

Beyond the Local Density Approximation

Characteristic Function and Transport Equation for the Particle Density

Charge density on the surface

Comparing the Density of Metals

Consequences for the Electron Density Distribution

Contour plot of the electron density

DENSITY IS THE RATIO OF MASS TO VOLUME

Definition of the Lagrangian density

Definition of the deformation density

Densities in the Wild

Density A property of matter representing the

Density A property of matter representing the mass per unit volume

Density Fluctuation within the Phases

Density Functional Theory and the Dirac-Coulomb Hamiltonian

Density Functional Theory and the Kohn-Sham Equation

Density Matrix of Crystals in the Hartree-Fock Method

Density Stratification in the Ocean

Density dependence of the inversion temperature

Density determination by the Archimedes principle

Density functional theory state of the art

Density near the Central Ion Is Determined by Electrostatics Poissons Equation

Density of States for the Electron Gas

Density of states at the Fermi level

Density of the elements

Density of the fill mass and subsoil Resistance against liquefaction

Density of the metals

Density of the nucleus

Density of the polymer coil

Density of the population

Density profiles at the interface

Density, Pressure, and Gravity as a Function of Depth within the Earth

Density, calculation of the

Density-Gradient Separations in the Ultracentrifuge

Density-functional Perturbation Theory and the Calculation of Response Properties

Dependence of current density on overvoltage. The Tafel equation

Determination of the Exchange Current Density from Polarization Resistance

Do We Know the Ground State Wave Function in Density Functional Theory

Effect of high optical densities on the Beer-Lambert-Bouguer law

Effective Charge Density Determined by the Osmotic Coefficient

Electron Density and the External Potentials

Electron density at the BCP

Electron density at the iron nucleus

Electron density distribution, by the

Electronic density - the superstar

Electrorefining of Metals. Concentration Polarization and the Limiting Current Density

Equation for the change in optical density of film dosimeters

Equation of motion for the density matrix

Equivalence of the electronic wave function and electron density

Estimate the Liquid Density of n-Nonane at

Evolution of the Density Matrix

Exchange-overlap Densities and the Chemical Bond

Expansion of the density matrix in

Experimental Data on the Exchange Current Density and Symmetry Coefficient

Explicit construction of the energy density functional within an orbit

Faradaic current density and the Butler-Volmer equation

Figures FIGURE 5.7 Bayesian posterior probability density of the fraction affected at median log (HC5) for cadmium

Fitting the Site Densities

Foundations of the Density-functional Theory

Fourier Expansion of the Electron Density

Fourier transform of the density

Fourier transform of the density correlation function

Full density models the SCDS-Pixel method

Functionals of the electronic density

Gradient vector field of the charge density

Gradient vector field of the electron density

Hirshfeld Division of the Molecular Ground-State Density

INFERENCES FROM THE POSTERIOR DENSITY

Identification with the Spectral Density Approach

Influence of the Charge Density

Invariance of the Density

Laplacian of the charge density

Laplacian of the density

Laplacian of the electron density

Least-squares minimization and the residual density

Limiting behavior of the probability density

Low Densities The Virial Equation

Measuring the Density of Irregularly Shaped Solids

Measuring the Density of Liquids

Mesoscopic Equation for the Particle Density

Model Runs Using the Site Density of Amorphous Iron Hydroxide and Goethite

Moments of the Power Spectral Density

Notations for the Density Matrix and Its Subsets

Phase contributions to the deformation density

Physical Constants of Liquids The Boiling Point and Density

Plot of the electron density

Plot of the electron density distribution

Probability density distribution function for the maximum information entropy

Properties determined by the electronic charge density

Properties of the Density Matrix

Properties of the One-Particle Density Matrix

Ps states in condensed matter the contact density parameter

Radial distribution of the electron density

Relation to the Spin Density

Representing the Electron Density

Solubility and the Cohesive Energy Density

Solubility parameter and the cohesive energy density

Solution for the density distribution

Solutions for the Density Gradient

Spectral density of the autocorrelation

Spin Density Distribution of the Soliton in Pristine Polyacetylene Detected by ENDOR

Stationary density distributions in the T-space

Status of the Gaussian Electrostatic Model, a Density-Based Polarizable Force Field

TOPOLOGY OF THE CHARGE DENSITY

Temperature dependence of the density

Test method for determination of the theoretical maximum specific gravity and density

The Basic Machinery of Density Functional Programs

The Basic Principles of Density Functional Theory

The Bulk-Regions Recombination Current Density

The Canonical Density and Thermodynamic Averages

The Charge Density in Extended Solids

The Critical Current Density

The Current Density Distribution in Homogeneous Fields

The Current Density on a Stepped Crystal Face

The Density Balance Detector

The Density Cumulant

The Density Detector

The Density Domain Approach to Chemical Bonding (DDA)

The Density Functional Method

The Density Functional Theory (DFT)

The Density Gradient

The Density Matrix

The Density Matrix Representation of Spin States

The Density Model

The Density of Carbon Dioxide

The Density of Irregularly Shaped Solids

The Density of Liquids

The Density of Primes

The Density of Solid and Liquid Water

The Density of States

The Density of States in an Alloy

The Density of Wood Tissue

The Density of a Gas

The Effect of Crystallinity on Polymer Density

The Electron Density

The Electron Density Equation

The Electron Density as Molecular Descriptor

The Electron Density from Experiment

The Electronic Properties and Density of States

The Equivalence of Current Density at an Interface and Reaction Rate

The Exchange Current Density

The Fluid Dynamic Storage Behaviour at 1 Bar of Two LNG or LPG Layers with Different Density

The Gibbs-Boltzmann Probability Density

The Ionized Atmosphere Ion Composition and Number Density

The Joint Density of States

The Lagrangian density

The Lagrangian density for diffusion

The Local Density Approximation

The Master Density Equation for Particulate Processes

The Master Density Function

The Number Density Function

The Pair Density

The Pair Density. Orbital-dependent Exchange-correlation Functionals

The Proportionality Constant Relating Electric Field and Current Density Specific Conductivity

The Quantum-Classical Density Operator for Electronically Excited Molecular Systems

The Relation of Current Density to Reaction Rate

The Spectral Density Function

The Total Electron Density

The air density

The band tail density of states distribution

The charge and current densities

The charge density in beryllium metal

The charge density in copper

The charge density in vanadium and chromium

The current density

The density correlation length

The density functional model

The density functional theory framework

The density matrix approach

The density matrix for a pure system

The density of a crystal

The density profile

The density-functional formalism

The electrolyte double layer surface tension, charge density, and capacity

The electron density in a crystal

The electronic density of states

The estimation of net atomic charges from calculated electron densities

The first-order density matrix

The frozen density energy

The interpretation of electron-density maps

The limit of low densities

The local density

The many to one correspondence between wavefunctions and densities

The measurement of density (specific gravity)

The nature of limits to deposition density

The one-electron density matrix

The pair density method

The parameters in a charge density refinement

The probability density function

The residual density

The resolution of an electron-density map

The spectral density

The spin density

The steady-state density and rate coefficient

The structure factor formalism in terms of atomic densities

The surface charge density

The total density

The two-electron density matrix

The use of densities or density ratios in specifications

The wavefunctions, probability densities and shape of

Time delay and the density of states

Topic 1.4. Representation of Electron Density by the Laplacian Function

Topological analysis of the electron density

Topological features of the electron density

Topological properties of the charge density

Topology of the electron density

Total Energies in the Local Density Approximation

Two-dimensional representations of the electron density distribution

Using Density to Find the Thickness of a Wire

Weight from Gas Density (the Dumas Bulb Method)

X-ray and the Electronic Density

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