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A curves

Distillation simulated by gas chromatography is a reproducible method for analyzing a petroleum cut it is appiicabie for mixtures whose end point is less than 500°C and the boiling range is greater than 50°C. The results of this test are presented in the form of a curve showing temperature as a function of the weight per cent distilled equivalent to an atmospheric TBP. [Pg.103]

The curve obtained can be transformed into a curve at a different pressure by the equations of Maxwell and Bonnel (see article 4.5.3.2.c). [Pg.163]

Connecting the measured points will result in a curve describing the area - depth relationship of the top of fhe reservoir. If we know the gross thickness (H) from logs we can establish a second curve representing the area - depth plot for the base of the reservoir. The area between the two lines will equal the volume of rock between the two markers. The area above the OWC is the oil bearing GRV. The other parameters to calculate STOIIP can be taken as averages from our petrophysical evaluation (see Section 5.4.). Note that this method assumes that the reservoir thickness is constant across the whole field. If this is not a reasonable approximation, then the method is not applicable, and an alternative such as the area - thickness method must be used (see below). [Pg.156]

The curve is symmetric from the middle of the slot. Hence the length of the defect is determined by the position of its edges at (x2+x3)/2 and -(x2+x3)/2 in the scanning direction of the probe. Of course this result is only true if we can distinguish the 5 zones on the curve. For other relative dimensions, for example a slot smaller than the probe (outer diameter), a curve like in set 1 is obtained, where the zones are confused. [Pg.146]

Restrictions for a curve of source movement reffer to as a completeness condition. This condition determines whether the information that is contained within some geometry of cone vertices is enough to perform an artifact-free reconstruction. [Pg.218]

Finch D. Cone-beam reconstruction with sources on a curve., SIAM J. Appl. Math., V. 45(4), 1985,p.665-673. [Pg.220]

This type of coil was prepared from copper cladded printed circuit board material by applying photolithographic techniques. The p.c. board material is available with difierent copper thicknesses and with either a stiff or a flexible carrier. The flexible material offers the opportunity to adapt the planar coil to a curved three dimensional test object. In our turbine blade application this is a major advantage. The thickness of the copper layer was chosen to be 17 pm The period of the coil was 100 pm The coils were patterned by wet etching, A major advantage of this approach is the parallel processing with narrow tolerances, resulting in many identical Eddy current probes. An example of such a probe is shown in fig. 10. [Pg.303]

With the reference block method the distance law of a model reflector is established experimentally prior to each ultrasonic test. The reference reflectors, mostly bore holes, are drilled into the reference block at different distances, e.g. ASME block. Prior to the test, the reference reflectors are scanned, and their maximised echo amplitudes are marked on the screen of the flaw detector. Finally all amplitude points are connected by a curve. This Distance Amplitude Curve (DAC) serves as the registration level and exactly shows the amplitude-over-distance behaviour" of the reference reflector for the probe in use. Also the individual characteristics of the material are automatically considered. However, this curve may only be applied for defect evaluation, in case the reference block and the test object are made of the same material and have undergone the same heat treatment. As with the DGS-Method, the value of any defect evaluation does not consider the shape and orientation of the defect. The reference block method is safe and easy to apply, and the operator need not to have a deep understanding about the theory of distance laws. [Pg.813]

An experimentally recorded DAC from a reference block and a curve calculated from the DGS-diagram are equal in many cases The pre-requirements of this equivalence are ... [Pg.813]

Corrections of the reference points of a curve may be made, if required by editing the DAC table or graphically editing the DAC points. [Pg.815]

The measuren.cnts are performed on a sample made from Inconell IN 718 placed at our disposal by Me oren- und Turbinen-Union Miinchen GmbH (MTU). The sample is of disk shape and has a curved side and a flat side, see also fig. 6. On the curved side MTU had detected a segregation reaching to the surface but with unknown depth. It had been detected by segregation etching and its existence was confirmed by eddy current testing. Both methods are successful only in such a special case where the segregation extends to the surface. [Pg.990]

Equation 11-3 is a special case of a more general relationship that is the basic equation of capillarity and was given in 1805 by Young [1] and by Laplace [2]. In general, it is necessary to invoke two radii of curvature to describe a curved surface these are equal for a sphere, but not necessarily otherwise. A small section of an arbitrarily curved surface is shown in Fig. II-3. The two radii of curvature, R and / 2[Pg.6]

It has long been known that the form of a curved surface of mercury in contact with an electrolyte solution depends on its state of electrification [108, 109], and the earliest comprehensive investigation of the electrocapillary effect was made by Lippmann in 1875 [110]. A sketch of his apparatus is shown in Fig. V-10. [Pg.192]

Fig. V-13. Composite x/ln a curve for 3-pentanol. The various data points are for different E values each curve for a given E has been shifted horizontally to give the optimum match to a reference curve for an E near the electrocapillary maximum. (From Ref. 134.)... Fig. V-13. Composite x/ln a curve for 3-pentanol. The various data points are for different E values each curve for a given E has been shifted horizontally to give the optimum match to a reference curve for an E near the electrocapillary maximum. (From Ref. 134.)...
The Kelvin equation (Eq. HI-18), which gives the increase in vapor pressure for a curved surface and hence of small liquid drops, should also apply to crystals. Thus... [Pg.262]

Using the temperature dependence of 7 from Eq. III-l 1 with n - and the chemical potential difference Afi from Eq. K-2, sketch how you expect a curve like that in Fig. IX-1 to vary with temperature (assume ideal-gas behavior). [Pg.342]

As a multidimensional PES for the reaction from quantum chemical calculations is not available at present, one does not know the reason for the surprismg barrier effect in excited tran.s-stilbene. One could suspect diat tran.s-stilbene possesses already a significant amount of zwitterionic character in the confomiation at the barrier top, implying a fairly Tate barrier along the reaction path towards the twisted perpendicular structure. On the other hand, it could also be possible that die effective barrier changes with viscosity as a result of a multidimensional barrier crossing process along a curved reaction path. [Pg.857]

Larson R S 1986 Simulation of two-dimensional diffusive barrier crossing with a curved reaction path Physica A 137 295-305... [Pg.865]

Powder diffraction studies with neutrons are perfonned both at nuclear reactors and at spallation sources. In both cases a cylindrical sample is observed by multiple detectors or, in some cases, by a curved, position-sensitive detector. In a powder diffractometer at a reactor, collimators and detectors at many different 20 angles are scaimed over small angular ranges to fill in the pattern. At a spallation source, pulses of neutrons of different wavelengdis strike the sample at different times and detectors at different angles see the entire powder pattern, also at different times. These slightly displaced patterns are then time focused , either by electronic hardware or by software in the subsequent data analysis. [Pg.1382]

The Laplace equation, which defines tire pressure difference, AP, across a curved surface of radius, r. [Pg.2761]

The equilibrium vapour pressure, P, over a curved surface is defined by tlie Kelvin equation... [Pg.2761]

The chemical potential of a curved surface is extremely critical in ceramic processing. It detemiines reactivity, tlie solubility of a solid in a liquid, tire rate of liquid evaporation from solid surfaces, and material transport during sintering. [Pg.2761]

Strictly speaking, this expression is correct for a semi-infinite region bounded by a plane wall and containing a gas at rest. Here it is applied to a bounded region surrounded by a curved wall, and the molecules have a drift velocity parallel to che wall. Knudsen was concerned that this drift velocity might invalidate the treatment, but Pollard and Present [8] showed Chat this is not che case. [Pg.8]

I he function/(r) is usually dependent upon other well-defined functions. A simple example 1)1 j functional would be the area under a curve, which takes a function/(r) defining the curve between two points and returns a number (the area, in this case). In the case of ni l the function depends upon the electron density, which would make Q a functional of p(r) in the simplest case/(r) would be equivalent to the density (i.e./(r) = p(r)). If the function /(r) were to depend in some way upon the gradients (or higher derivatives) of p(r) then the functional is referred to as being non-local, or gradient-corrected. By lonlrast, a local functional would only have a simple dependence upon p(r). In DFT the eiK igy functional is written as a sum of two terms ... [Pg.147]

For this reduction use preferably a i litre round-bottomed flask having 3 necks (Fig. 23(G), p. 46), the two necks at the flanks being straight (to avoid the obstruction, during the addition of sodium, which a curved neck might cause). Fit the central neck with a stirrer, one of the side necks with a reflux water-condenser, and the other with a glass or rubber stopper. [Pg.225]

The apparatus (Fig. 82), which is constructed throughout of glass, consists of a pear-shaped bulb A (of about 5 ml. capacity) in which the solution is boiled, and which has a short length of platinum wire fused through its lowest point to assist steady boiling. The bulb A is connected near its base by a curved narrow tube B to a vertical condenser C, and from its apex by a similar tube D, undulating as shown, to the cup E. A larger outer cup F is fused to the lower neck of E as shown. [Pg.443]

On a curved surface the virtual conductivity is found analogously as... [Pg.100]

Let S be an open, two-sided surface bounded by a curve C, then the line integral of vector A (ciiiwe C is traversed in the positive direction) is expressed as... [Pg.257]

In the first pari of this project, the analytical form of the functional relationship is not used because it is not known. Integration is carried out directly on the experimental data themselves, necessitating a rather different approach to the programming of Simpson s method. In the second part of the project, a curve fitting program (TableCurve, Appendix A) is introduced. TableCurve presents the area under the fitted curve along with the curve itself. [Pg.24]

Deviations from a curve thought to be a straight line y = mx + b, not passing through the origin (b 0), are... [Pg.63]

Plotting the left side of Eq. (3-22) as a function of gives a curve with as the slope and E° as the intercept. Ionic interference causes this function to deviate from lineality at m 0, but the limiting (ideal) slope and intercept are approached as OT 0. Table 3-1 gives values of the left side of Eq. (3-22) as a function of The eoneentration axis is given as in the corresponding Fig. 3-1 beeause there are two ions present for each mole of a 1 -1 electrolyte and the concentration variable for one ion is simply the square root of the concentration of both ions taken together. [Pg.67]

Disconnection An analytical operation, which breaks a bond and converts a molecule into a possible starting material. The reverse of a chemical reaction. Symbol and a curved line drawn through the bond being broken. Called a dislocation by some people. [Pg.4]

One very popular technique is to use QSAR. It is, in essence, a curve-fitting... [Pg.113]

A curve fit is then done to create a linear equation, such as... [Pg.244]

A curved arrow shown as a single barbed fishhook signifies the movement of one electron Normal curved arrows track the movement of a pair of electrons... [Pg.169]

FIGURE 9 5 (a) Curved arrow notation and (b) transition state for electrophilic addition of a hydrogen halide HXto an alkyne... [Pg.378]


See other pages where A curves is mentioned: [Pg.100]    [Pg.708]    [Pg.900]    [Pg.1382]    [Pg.2503]    [Pg.2761]    [Pg.7]    [Pg.309]    [Pg.594]    [Pg.9]    [Pg.102]    [Pg.108]    [Pg.1]    [Pg.3]    [Pg.122]   


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Derivative of a Curve

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Establishment of a Working Curve

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Polarization Curve of a Single Electrode

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Pressure drop across a curved interface

Recombination on a Repulsive Potential Curve

Simulation of Titration Curves Using a Single Master Equation

Simulation of the curves displaying a plateau

Single-Phase Flow in a Curved Pipe

Solubility curve of an addition compound in a non-ideal solution

Solubility curve of an addition compound in a perfect solution

Stress-Strain Curve of a Single Chain

Tangent to a curve

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