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Displacement discrete

An inmortant caveat The lines are shown as continuous functions, a considerable oversimplification. Pumps, pipes, valves, and even membrane assemblies come in discrete sizes and capacities, sometimes giving a project cost with a sharper minimum and one displaced from the ideal minimum. Every process has different characteristics, but the general shape of a broad economic minimum is characteristic. [Pg.2028]

This type of chromatographic development will only be briefly described as it is rarely used and probably is of academic interest only. This method of development can only be effectively employed in a column distribution system. The sample is fed continuously onto the column, usually as a dilute solution in the mobile phase. This is in contrast to displacement development and elution development, where discrete samples are placed on the system and the separation is subsequently processed. Frontal analysis only separates part of the first compound in a relatively pure state, each subsequent component being mixed with those previously eluted. Consider a three component mixture, containing solutes (A), (B) and (C) as a dilute solution in the mobile phase that is fed continuously onto a column. The first component to elute, (A), will be that solute held least strongly in the stationary phase. Then the... [Pg.8]

Oriented strandboard (OSB) resins are quite similar to plywood resins, though they tend to be lower in alkalinity and higher in solids. Sinee OSB resins are sprayed onto dry wood in small discrete droplets rather than applied in glue lines, the problems associated with holding the glue on the wood surfaee are not usually issues of coneem. Adhesive dry-out and loss of flow displace over-penetration as major difficulties. [Pg.894]

Table 3.3 summarizes the history of the development of wave-profile measurement devices as they have developed since the early period. The devices are categorized in terms of the kinetic or kinematic parameter actually measured. From the table it should be noted that the earliest devices provided measurements of displacement versus time in either a discrete or continuous mode. The data from such measurements require differentiation to relate them to shock-conservation relations, and, unless constant pressures or particle velocities are involved, considerable accuracy can be lost in data processing. [Pg.62]

Optical devices or optical systems have provided most of the available strong shock data and were the primary tools used in the early shock-compression investigations. They are still the most widely used systems in fundamental studies of high explosives. The earliest systems, the flash gap and mirror systems on samples, provided discrete or continuous measurements of displacement versus time. [Pg.65]

Wliile all the flame arrester types disenssed above have a solid arresting element (matrix), the hydranlic (liqnid seal) flame arrester contains a liqnid, nsnally water, to provide a flame barrier. It operates by breaking np the gas flow into discrete bnbbles by means of an internal device to qnench the flame. A mechanical nonretnrn valve (check valve) is sometimes incorporated to prevent the displacement of liqnid dnring or after a flame event (deflagration or detonation). [Pg.87]

By this discretization in the polar coordinates, one can allow an atom to be displaced to one of the 121 (=1+8+16+24+32+40) discrete points around each reference lattice point. [Pg.51]

We have solved the set of integral equations on the pair distribution functions by discretizing them. This is equivalent to allowing the atomic displacements to finite number of points. When they are discretized, to solve them is a straightforward application of the exsisting CVM. [Pg.52]

Frequency-domain data are obtained by converting time-domain data using a mathematical technique referred to as Fast Fourier Transform (FFT). FFT allows each vibration component of a complex machine-train spectrum to be shown as a discrete frequency peak. The frequency-domain amplitude can be the displacement per unit time related to a particular frequency, which is plotted as the Y-axis against frequency as the X-axis. This is opposed to time-domain spectrums that sum the velocities of all frequencies and plot the sum as the Y-axis against time... [Pg.668]

The frequency-domain format eliminates the manual effort required to isolate the components that make up a time trace. Frequency-domain techniques convert time-domain data into discrete frequency components using a mathematical process called Fast Fourier Transform (FFT). Simply stated, FFT mathematically converts a time-based trace into a series of discrete frequency components (see Figure 43.19). In a frequency-domain plot, the X-axis is frequency and the Y-axis is the amplitude of displacement, velocity, or acceleration. [Pg.685]

Again an approach that chooses the displacement a to maximize the probability of obtaining the received data appears reasonable. This is illustrated in Fig. 4, where the two possible locations of the positioning of the pdf in Fig. 4(a) is clearly more consistent with the observed data than Fig. 4(b). Let us assume an ideal detector, one with a large number of pixels and with the only noise resulting from the discrete nature of photons. The probability of D photons in a pixel is given by... [Pg.386]

Qnantized adhesion was observed by Hoh et al. [53] for a SisN4 tip breaking contact with a glass snrface in water, which had been NaOH adjusted to pH 8.5. As described at the beginning of Section IILA, a more accurate description of the measurement would be quantized displacement, which can be evaluated as quantized adhesion by multiplying the observed displacement by the lever stiffness. The authors speculate that their observations conld be explained either by the breaking of discrete numbers of hydrogen bonds between the tip and surface or by the breakdown of the continuum properties of water in close proximity to a solid surface. [Pg.37]

To represent the elasticity and dispersion forces of the surface, an approach similar to that of Eqs. (3) and (4) can be taken. The waU molecules can be assumed to be smeared out. And after performing the necessary integration over the surface and over layers of molecules within the surface, a 10-4 or 9-3 version of the potential can be obtained [54,55], Discrete representation of a hexagonal lattice of wall molecules is also possible by the Steele potential [56], The potential is essentially one dimensional, depending on the distance from the wall, but with periodic variations according to lateral displacement from the lattice molecules. Such a representation, however, has not been developed in the cylindrical pore... [Pg.630]

The concentration of cations at discrete pH values which resulted in the highest observed PE permeability was obtained at pH 8.0 and 0.15M NaCl, pH 3.8 and 0.4M NaCl, or pH 3.8 and O.IM CaCl2. An increase of pH and/or cation concentration promoted an increase in PE permeability. Conversely, flux decreased with an increase in cation concentration or pH. At similar pH and cation concentrations that stimulate PE activity by competitive displacement, permeation of PE through a 30 kD MWCO UF membrane was observed. At low pH and no salt, the low level of pectin present in the PE extracts bound PE and prevented permeation. [Pg.480]

Surfactant blends of interest will exhibit clouding phenomena in aqueous solutions undergoing a phase transition from a one phase system to a two phase system at a discrete and characteristic temperature, referred to as the Cloud Point (CP). This value indicates the temperature at which sufficient dehydration of the oxyethylene portion of the surfactant molecule has occurred and this results in its "displacement" from solution. The addition of lyotropic salts will depress the CP, presumably due to the promotion of localised ordering of water molecules near the hydrophilic sheath of the surfactant molecule (8). Furthermore, the addition of different oils to surfactant solutions can induce either an elevation or a depression of the recorded CP and can be used to qualitatively predict the PIT (8x9). [Pg.320]

Fig. 3.8. Transition matrix of move proposal probabilities for the Lennard-Jones fluid at p = 0.88 and N = 110. The energy range of —700 to —500 in Lennard-Jones units has been discretized into 100 bins. Due to the adjustment of the random displacement moves to achieve 50% acceptance, the transition probabilities are highly banded. The tuned moves change the potential energy by only a small amount, and as a result, each energy level is effectively only connected to a few neighbors... Fig. 3.8. Transition matrix of move proposal probabilities for the Lennard-Jones fluid at p = 0.88 and N = 110. The energy range of —700 to —500 in Lennard-Jones units has been discretized into 100 bins. Due to the adjustment of the random displacement moves to achieve 50% acceptance, the transition probabilities are highly banded. The tuned moves change the potential energy by only a small amount, and as a result, each energy level is effectively only connected to a few neighbors...
Fick s (continuum) laws of diffusion can be related to the discrete atomic processes of the random walk, and the diffusion coefficient defined in terms of Fick s law can be equated to the random-walk displacement of the atoms. Again it is easiest to use a one-dimensional random walk in which an atom is constrained to jump from one... [Pg.485]

As mentioned earlier, a random and statistical cyclization with two different and regio-defined Ti-compounds would produce a synthetically unattractive mixture of ten different zirconacycles. In reality, however, there are a few factors that can be exploited to produce a single desired zirconacycle. A systematic investigation has revealed that there are several discrete types offive-membered zirconacycle formation, as shown in Scheme 1.53 [88,89] (Generalization 20). In the Type I reaction, the cross-selective cyclization is kinetically favored. Presumably, little ethylene is displaced during the reaction. Type I reactions cannot be readily observed with ZrCp2 complexes with 1-butene. In contrast, Type II cyclization must be thermodynamically controlled, as 1-butene is readily displaced by a number of better Ti-ligands. It is predicted, however, that the cross-combination of the two Ti-com-... [Pg.34]

Due to its large discrete jumps, rotation around the helix axis is not a continuous Gaussian random process, so its actual mean squared angular displacement cannot be used directly in C (t). However, <<5z(/)2> for the equivalent Gaussian random process that makes the same contribution to the FPA is obtained from the relation... [Pg.201]

The model of Fig. IB is taken from a review by van Holde et al. [3] which I refer to as the disruptive model. In this model the polymerase causes conditions (step A) which promote not only the displacement of the entry site H2A, H2B dimer from DNA, but also from the H3, H4 tetramer (step B). As a result of this disruption, the polymerase is free to transcribe through the tetramer alone without a general displacement from its associated DNA (step C). The H2A, H2B dimer is now free to reassociate to the vacated entry site (step D) to re-establish contacts with both the DNA and the H3, H4 tetramer. As transcription proceeds into the exit site H2A, H2B dimer, these proteins are now displaced from both the DNA and the H3, H4 tetramer in a similar manner as the entry site H2A, H2B dimer (step E). A positive feature with regard to this model is that by displacement of H2A, H2B, the polymerase is able to transcribe the DNA with half the histones displaced prior to transcription. Therefore both models, spooling and disruptive , describe mechanisms which would favorably enhance the process of transcription. Support for the disruptive model comes from the substantial in vivo information which suggests that nucleosomes undergo substantial disruption during transcription, as was described in the previous section. Of particular note are those observations which indicate that a discrete population of H2A, H2B... [Pg.479]

Continuous analysis requires flexible tubes which are not attacked by the materials under examination, and this places certain limitations on the scope of the method. Certain reactive and corrosive materials cannot he satisfactorily pumped, although advances have been made in the development of inert plastics and other synthetic materials. Displacement pumping with the aid of a liquid compatible with sample and reagents provides an alternative, though generally inconvenient, approach. No such limitations arise in discrete analysers because there is no restriction on the choice of materials for sample and reagent containment. [Pg.28]

The non-classical ion may exist as edge or face protonated nortricyclene, represented by stmcture [9], as an alternative. This species is not a resonance stmcture of [7] or [8]. If it is a discrete intermediate, one might expect to be able to detect the displaced proton via a suitably designed exchange experiment. [Pg.180]


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See also in sourсe #XX -- [ Pg.309 ]




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