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Differences between

There is a significant difference between the results shown in Figure 2 and calculated results given in Brit. Chem. Eng. Proc. Tech. 16 1036 (1971). We believe the latter to be in error. [Pg.91]

Unfortunately, many commonly used methods for parameter estimation give only estimates for the parameters and no measures of their uncertainty. This is usually accomplished by calculation of the dependent variable at each experimental point, summation of the squared differences between the calculated and measured values, and adjustment of parameters to minimize this sum. Such methods routinely ignore errors in the measured independent variables. For example, in vapor-liquid equilibrium data reduction, errors in the liquid-phase mole fraction and temperature measurements are often assumed to be absent. The total pressure is calculated as a function of the estimated parameters, the measured temperature, and the measured liquid-phase mole fraction. [Pg.97]

The sum of the squared differences between calculated and measures pressures is minimized as a function of model parameters. This method, often called Barker s method (Barker, 1953), ignores information contained in vapor-phase mole fraction measurements such information is normally only used for consistency tests, as discussed by Van Ness et al. (1973). Nevertheless, when high-quality experimental data are available. Barker s method often gives excellent results (Abbott and Van Ness, 1975). [Pg.97]

In the maximum-likelihood method used here, the "true" value of each measured variable is also found in the course of parameter estimation. The differences between these "true" values and the corresponding experimentally measured values are the residuals (also called deviations). When there are many data points, the residuals can be analyzed by standard statistical methods (Draper and Smith, 1966). If, however, there are only a few data points, examination of the residuals for trends, when plotted versus other system variables, may provide valuable information. Often these plots can indicate at a glance excessive experimental error, systematic error, or "lack of fit." Data points which are obviously bad can also be readily detected. If the model is suitable and if there are no systematic errors, such a plot shows the residuals randomly distributed with zero means. This behavior is shown in Figure 3 for the ethyl-acetate-n-propanol data of Murti and Van Winkle (1958), fitted with the van Laar equation. [Pg.105]

If there is a significant difference between the effect of pressure on... [Pg.44]

The temperature difference between stages can be manipulated by changing the heat transfer area. Figure 3.136 shows the effect of a decrease in heat transfer area. [Pg.87]

The wave function T i oo ( = 11 / = 0, w = 0) corresponds to a spherical electronic distribution around the nucleus and is an example of an s orbital. Solutions of other wave functions may be described in terms of p and d orbitals, atomic radii Half the closest distance of approach of atoms in the structure of the elements. This is easily defined for regular structures, e.g. close-packed metals, but is less easy to define in elements with irregular structures, e.g. As. The values may differ between allo-tropes (e.g. C-C 1 -54 A in diamond and 1 -42 A in planes of graphite). Atomic radii are very different from ionic and covalent radii. [Pg.45]

Apolar stationary phases having no dipolar moments, that is their center of gravities of their positive and negative electric charges coincide. With this type of compound, the components elute as a function of their increasing boiiing points. The time difference between the moment of injection and the moment the component leaves the column is called the retention time. [Pg.21]

The naphthenic carbon percentage is the difference between 100 and the sum of the above concentrations. [Pg.61]

The A/ 100 corresponds to the difference between the RON of the motor fuel and that of the fraction distilled at 100°C. The determination is carried out in three stages ... [Pg.200]

The differences between the measured cetane numbers and the cetane indices calculated by the above formula are relatively small for cetane indices between 40 and 55. Nevertheless, for diesel fuels containing a pro-cetane additive, the CCl will be much less than the actual value (refer to paragraph d). [Pg.220]

It is mainly in cold behavior that the specifications differ between bome-heating oil and diesel fuel. In winter diesel fuel must have cloud points of -5 to -8°C, CFPPs from -15 to -18°C and pour points from -18 to 21°C according to whether the type of product is conventional or for severe cold. For home-heating oil the specifications are the same for all seasons. The required values are -l-2°C, -4°C and -9°C, which do not present particular problems in refining. [Pg.233]

For other physical properties, the specification differences between diesel fuel and home-heating oil are minimal. Note only that there is no minimum distillation end point for heating oil, undoubtedly because tbe problem of particulate emissions is much less critical in domestic burners than in an engine. [Pg.233]

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]

The classification of motor oils has not been completed in the ISO standard because the technical differences between motors in different parts of the world, particularly Europe and the United States, make the implementation of a single system of classification and specifications very difficult. In practice, different systems coming from national or international organizations are used. The best known is the SAE viscosity classification from the Society of Automotive Engineers, developed in the United States. [Pg.276]

All these organizations have developed numerous working procedures, with very little difference between each other. These procedures seem at first heavy and cumbersome, but following them allows a consensus to be reached. Thus, for example, free access for all to the standardization commissions work is guaranteed, and the existence of lobbies is avoided. [Pg.296]

Refining alone can not, economically, provide a fuel to meet specifications the role of organic lead derivatives has long been to make up the difference between the octane number of the clear fuel and the octane required by legislation. [Pg.346]

Consider that at low temperatures, a lubricant is a poor solvent for polymer chains. When the temperature increases, interactions between polymer chains decrease the space occupied by the polymer ball takes on greater volume and consequently, the viscosity decrease due to the lubricant temperature increase is compensated by the unfolding of the polymer chain and the result is a reduction of the difference between the viscosities at low and high temperature, and therefore an Increase in viscosity index. [Pg.355]

Reservoir rocks are either of clastic or carbonate composition. The former are composed of silicates, usually sandstone, the latter of biogenetically derived detritus, such as coral or shell fragments. There are some important differences between the two rock types which affect the quality of the reservoir and its interaction with fluids which flow through them. [Pg.13]

In a reservoir at initial conditions, an equilibrium exists between buoyancy forces and capillary forces. These forces determine the initial distribution of fluids, and hence the volumes of fluid in place. An understanding of the relationship between these forces is useful in calculating volumetries, and in explaining the difference between free water level (FWL) and oil-water contact (OWC) introduced in the last section. [Pg.120]

Inside the capillary tube, the capillary pressure (P ) is the pressure difference between the oil phase pressure (PJ and the water phase pressure (P ) at the interface between the oil and the water. [Pg.122]

This is consistent with the observation that the largest difference between the oil-water interface and the free water level (FWL) occurs in the narrowest capillaries, where the capillary pressure is greatest. In the tighter reservoir rocks, which contain the narrower capillaries, the difference between the oil-water interface and the FWL is larger. [Pg.123]

The difference between the OWC and the FWL is greater in tight reservoirs, and may be up to 30m difference. A difference between gas-oil contact and free oil level exists for the same reasons, but is much smaller, and is often neglected. [Pg.124]

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]

As discussed at the beginning of this section, the value of information from appraisal is the difference between the outcome of the decision with the information and the outcome of the decision without the information. [Pg.179]

The main differences between oil and gas field development are associated with ... [Pg.193]

One of the major differences in fluid flow behaviour for gas fields compared to oil fields is the mobility difference between gas and oil or water. Recall the that mobility is an indicator of how fast fluid will flow through the reservoir, and is defined as... [Pg.196]

The difference between the flowing wellbore pressure (P, ) and the average reservoir pressure reservoir pressure (P) is the pressure drawdown (AP q). [Pg.216]


See other pages where Differences between is mentioned: [Pg.141]    [Pg.345]    [Pg.66]    [Pg.103]    [Pg.105]    [Pg.152]    [Pg.155]    [Pg.210]    [Pg.211]    [Pg.295]    [Pg.373]    [Pg.36]    [Pg.57]    [Pg.62]    [Pg.184]    [Pg.198]    [Pg.206]    [Pg.223]    [Pg.299]    [Pg.79]    [Pg.122]    [Pg.193]    [Pg.205]   


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A Equilibria between Isomeric Ions Differing in the Site of Proton Attachment

Alkenes difference between

Amphiphilic block copolymers differences between surfactants

Analysis Between the Different CYP Crystal Structures

Annex S - Differences between 1996 and 2004 versions

Approach differences between procedures

Are there any differences between tillage management in organic and conventional agriculture

Aryl-binding sites, differences between

Between Different Metals in Carbonyls and Their Derivatives

Between different phases

Bonding difference between

Bonds between different atoms

Chemical Interactions to the Adhesion Between Evaporated Metals and Functional Croups of Different Types at Polymer Surfaces

Chemical differences between living and

Chemical differences between living and dead

Chemical differences between living and dead plants

Chemical reaction kinetics difference between heterogeneous

Chemical reaction kinetics difference between homogeneous

Chiral drugs difference between enantiomers

Clay morphological differences between

Clustering) differences between

Commercial starches, differences between

Comparative Studies between Different Aqueous Electrolytes

Comparison Between Different Radiation and Scattering Processes

Comparison Between the Different Methods

Comparison between Different Models

Competition Between Different Nitrogens

Competition Experiments Between Different Ligands

Competition between Different Pathways for Photosynthetic Reductants

Competition between different ligands

Condensation Between Coordinately Saturated Species with Different Oxidation States

Confidence Intervals for the Difference Between Treatment Group Means

Confidence intervals for the difference between two proportions

Conformers energy differences between

Connections between different bases

Continuous phases, differences between

Copolymer differences between conventional

Crosstalk Between Different Signaling Systems

Density difference, between liquid and gas

Difference Between Cp and

Difference Between Novolac and Resole

Difference between evolution during

Difference between evolution during solution

Difference between flight and ground

Difference between reversed-phase

Difference between the volumes of activation

Difference spectrum between polymer

Differences Between Bridges

Differences Between Thermal and Thermo-Oxidative Degradation of Phosphorus Containing Polysulfones

Differences Exist between Eukaryotic and Prokaryotic Transcription

Differences between Elastomers and Thermoplasts

Differences between Force Fields

Differences between Gymnosperms

Differences between Gymnosperms and Angiosperms

Differences between J and

Differences between Metals

Differences between Photochemical and Thermal Reactions

Differences between Rice Production Systems

Differences between STM and AFM

Differences between Three- and Two-Electrode Cell Supercapacitor Characterizations

Differences between academic and

Differences between calculated and

Differences between calculated and measured values

Differences between field-exposed magnesium (Mg) and accelerated tests

Differences between flight- and

Differences between human and

Differences between mutant and wild-type

Differences between outsourcing and offshoring

Differences between process analyzers and laboratory analysis

Differences between species

Differences between the Elements Silicon and Carbon

Different Substituent Effects Between Monomer and Polymer

Diffusion difference between samples

Diffusive boundary between different phases

Directionality and Differences Between Theories

Dissolution difference between limestones

Drug discovery differences between

Effect of Sub-cooling Difference Between Layers

Elastomers comparisons between different

Electrochemistry boundary between different phases

Electrostatic Interaction Between Different Surfaces

Enantiomers differences between

Energy Conversion A Basic Difference between Chemical and Electrochemical Reactions

Energy difference between £ and

Energy difference, between axial and

Energy difference, between axial and equatorial conformers

Energy difference, between singlet and triplet

Energy differences between states

Enthalpy difference between polymorphs

Equilibria Between Complexes with Different Coordination Numbers

Equilibrium between different phases

Equilibrium between different phases in ideal solutions

Fresnel difference between polarizations

Galvani potential difference, interface between

General considerations and comparison between different chromatographic methods

Geometrical isomers calculating energy difference between

H , differences between

Heat capacity pressure, difference between

Height differences between groups

Heterogeneous chemical reactions difference between homogeneous

INDEX difference between

Interaction forces between different

Interrelationship between Different Lipid Categories

Isomers binding differences between

Junction Potentials between Different Solvents

Knowing the difference between implicit and explicit scoring

Laboratory differences between industrial

Lipid differences between hydrogen-bonding

Liquid junction potential between different solvents

Major differences between oil and gas field development

Major differences between various dyes

Mass differences between molecular formulas

Mean, differences between means

Means difference between two

Metabolite chemical differences between

Metal Atoms between Different Ligand Sites

Metal-enzyme complexes difference between metalloenzymes

Migration between Different Ligand Sites

Minimizing difference between theoretical

Mobility difference between enantiomers

Molecular Interactions Determining the Partitioning of Organic Compounds Between Different Phases

Muscle differences between other striated

Nuclear magnetic resonance spectroscopy energy difference between spin states

Odors enantiomeric differences between

Orbitals energy differences between subshells

Overall relationship between mass flow and pressure difference

Packings difference between older

Partial least-squares analysis between different

Particle maximum temperature difference between

Pharmacokinetic properties differences between

Pharmacological differences between

Pharmacological differences between Pharmacology

Pharmacological differences between cardiovascular effects

Pharmacological differences between distribution

Pharmacological differences between drug transporters

Pharmacological differences between men and women

Pharmacological differences between pathways

Pharmacological differences between pharmacodynamics

Pharmacological differences between pharmacokinetics

Photochemical reactions differences between thermal

Physiological differences between

Pictorial descriptions of the phase difference between bound and continuum vibrational wavefunctions

Potential difference between dropping

Potential difference between two contacting phases

Potential difference between two phases

Potential differences between organic liquids and aqueous solutions

Proton transfer between chemically different acceptor

Psychometric tests differences between studies

Quantitative Correlations Between Strain and Stability Differences

Relations Between Different Material Coefficients

Relationships between Different Types of Delocalized Systems

Retention difference between

Review of structural differences between solids, liquids, and gases

Sampling differences between studies

Secondary metabolite chemical differences between

Significance of Differences between Means

Skill 22.4 Demonstrate an understanding of the differences between real and ideal gases

Special differences between the second and subsequent Periods

Specific surfaces differences between

Stability difference between diastereomers

Stereochemistry chemical differences between enantiomers

Strong, weak hydrogen bonds, difference between

Structure difference between conformers

Structure-activity relationships between different SARs

Summary of differences between random and systematic failure

Supported Liquid-phase Catalyst Sandwiched between Two Different Membranes

Synchronization Between Neurons at Different Dynamic States

Systematic differences between methods

Technical differences between repair options

Temperature Difference Between Bulk Fluid and Catalyst Surface

Temperature difference between

Temperature difference between surface and

The Difference Between Initiation and Induction Phenomena

The correlation between different normalisation methods

The differences between carbon and proton NMR

Thermal equilibrium, between different spin

Thermal equilibrium, between different spin states

Three-electron bonds between different heteroatoms

Transition Between Different Episode Patterns The Conceptual Approach

Transmission spectroscopy, difference between

Virus differences between bacteriophages

Voltage Potential difference between two

Voltage difference between electrodes

Wall boundary between different phases

Wear Rates Between Different Clinical Studies

What Is the Difference between Hard and Soft Contact Lenses

What is the Difference Between Nanofiltration and Reverse Osmosis

What is the difference between an isotope and a nuclide

Whole plant differences between

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