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Order of system

A low order of systemic toxicity was found in chronic feeding studies with rats. Administered in the diet for 2 years 0.215% sodium metabisulfite caused no adverse effects. Reproductive parameters were not affected in three-generation feeding smdies in rats at concentrations up to 13mmol/kg /day. ... [Pg.637]

Equations (2.4.10a) to (2.4.101) are six first order ODEs for the six unknown variables y to ye- Note that the order of system is increased from four to six in CMM, while the governing equation is transformed from a boundary value problem to an initial value problem. To solve these six equations, we therefore need to generate initial conditions for the unknowns. As we know the property of the fundamental solutions in the free stream, we can use that information to generate the initial conditions for yi to r/g. As at r/ —> 00 and (f>s, therefore we can estimate the... [Pg.39]

After defining the local composition and preferential solvation, we turn to discuss these quantities in more detail first, in three-component systems and later in two-component systems. This order of systems is not accidental. The concept of PS was first defined and studied only in three-component systems a solute s diluted in a two-component solvent. It is only in such systems that the concept of PS could have been defined within the traditional approach to solvation. However, with the new concept of solvation, as defined in section 7.2, one can define and study the PS in the entire range of compositions of two-component systems. In the last section of this chapter, we present a few representative examples of systems for which a complete local characterization is available. These examples should convince the reader that local characterization of mixture is not only equivalent to its global characterization, but also offers an alternative and more informative view of the mixture in terms of the local properties around each species in the mixture. We also present here a brief discussion of two difficult but important systems electrolyte and protein solutions. It is hoped that these brief comments will encourage newcomers into the field to further study these topics of vital importance. [Pg.262]

In the glassy state the liquid crystalline order of systems oriented in a magnetic field could be determined by deuterium NMR of spedficafiy labefled compounds Figure 5,11 illustrates the decreasing order fi-om mesogen to spacer... [Pg.92]

Pyrethrum is comprised of the dried flowers of Chrysanthemum cinerariaefolium containing not less than 1% pyrethrins. Pyrethrin esters constitute a powerful degradable contact insecticide. They have a low order of systemic toxicity to man and produce no harmful residues on food crops. The flowers and extracts for pyrethrum are imported from Kenya and... [Pg.784]

In Figure 2.14(b), we have shown the variations in the degree of order of system as a function of the quantity -kB772M AB, in the case of an A3B solid - i.e. one where Xa = 0.75 and Xb = 0.25. As we can see, when the temperature is lowered, a second minimum of the function F(s) appears for a value = 0 of the degree of order. The first minimum is still at s = 0. The position of this second minimum descends as the temperature decreases. The first minimum corresponds to a metastable state, represented by the branch ba in Figure 2.14(b), and the second minimum corresponds to the state of stable thermodynamic equilibrium, represented by the branch ab. Between the two minima, obviously, there is a maximum which corresponds to an unstable state. This state corresponds to the branch be in Figure 2.14(b). [Pg.120]

Also, if there are two separators, the order of separation can change. The tradeoffs for these two alternative flowsheets will be different. The choice between different separation sequences can be made using the methods described in Chap. 5. However, we should be on guard to the fact that as the reactor conversion changes, the most appropriate sequence also can change. In other words, different separation system structures become appropriate for different reactor conversions. [Pg.246]

Ultrasonic absorption is used in the investigation of fast reactions in solution. If a system is at equilibrium and the equilibrium is disturbed in a very short time (of the order of 10"seconds) then it takes a finite time for the system to recover its equilibrium condition. This is called a relaxation process. When a system in solution is caused to relax using ultrasonics, the relaxation lime of the equilibrium can be related to the attenuation of the sound wave. Relaxation times of 10" to 10 seconds have been measured using this method and the rates of formation of many mono-, di-and tripositive metal complexes with a range of anions have been determined. [Pg.411]

An fuel-air mixture explosion can be initiated by a sudden discharge of static electricity. Yet, while flowing in systems, a fluid develops an electrical charge which will take as long to dissipate as the fluid is a poor conductor. The natural electrical conductivity of jet fuel is very low, on the order of a few picosiemens per meter, and it decreases further at low temperature. [Pg.251]

There are, however, technological means available to burn incompletely desulfurized fuels at the same time minimizing SO2 emissions. In the auto-desulfurizing AUDE boiler developed by IFF, the effluent is treated in place by an absorbent based on lime and limestone calcium sulfate is obtained. This system enables a gas desulfurization of 80% it requires nevertheless a relatively large amount of solid material, on the order of 200 kg per ton of fuel. [Pg.256]

The cost of implementing CAO depends of course on the system installed, but for a new field development is likely to be in the order of 1 -5% of the project capital expenditure, plus 1-5% of the annual operating expenditure. [Pg.282]

Where Ui denotes input number i and there is an implied summation over all the inputs in the expression above A, Bj, C, D, and F are polynomials in the shift operator (z or q). The general structure is defined by giving the time delays nk and the orders of the polynomials (i.e., the number of poles and zeros of the dynamic models trom u to y, as well as of the noise model from e to y). Note that A(q) corresponds to poles that are common between the dynamic model and the noise model (useful if noise enters system close to the input). Likewise Fj(q) determines the poles that are unique for the dynamics from input number i and D(q) the poles that are unique for the noise N(t). [Pg.189]

The geometric compensation by means of a gradiometric coil is realised by placing the SQUID exactly between the two halfs of the coil, in order to detect only the response of the sample. In both cases we could achieve a reduction of the excitation field at the location of the SQUID of up to 1000. Electronic and geometric compensation together leads to an improvement of six orders of magnitude in the dynamic range, compared to a system without excitation field compensation. [Pg.259]

For this experiment, as well as for the microtomography ( 3.2) we used the commercial desktop microtomography system Skyscan 1072 [5], the setup of which is sketched in Figure 1. For this instrument, which is designed to study relatively large objects with a diameter up to 50 mm, the source size is 8 pm, the distance source-detector is about 50 cm and the effective resolution of the detector is about 80 pm. For this system and this object, the global effective resolution a is estimated to be of the order of 50 to 100 pm [6]. [Pg.576]

It should be noted that these results are only preliminary and have to be considered as a proof of concept. As is clear from eq. (2) the phase contrast can be improved drastically by improving the global resolution and sensitivity of the instrument. Currently, a high resolution desktop system is under construction [5] in which the resolution is much better than that of the instrument used in this work, and in which the phase contrast is expected to be stronger by one order of magnitude. [Pg.577]

At first we tried to explain the phenomenon on the base of the existence of the difference between the saturated vapor pressures above two menisci in dead-end capillary [12]. It results in the evaporation of a liquid from the meniscus of smaller curvature ( classical capillary imbibition) and the condensation of its vapor upon the meniscus of larger curvature originally existed due to capillary condensation. We worked out the mathematical description of both gas-vapor diffusion and evaporation-condensation processes in cone s channel. Solving the system of differential equations for evaporation-condensation processes, we ve derived the formula for the dependence of top s (or inner) liquid column growth on time. But the calculated curves for the kinetics of inner column s length are 1-2 orders of magnitude smaller than the experimental ones [12]. [Pg.616]

In the third order of long-range perturbation theory for a system of tluee atoms A, B and C, the leading nonadditive dispersion temi is the Axilrod-Teller-Mutd triple-dipole interaction [58, 59]... [Pg.194]

Assuming that the system has no pennanent dipole moment, tire existence ofP(t) depends on a non-stationary j induced by an external electric field. For weak fields, we may expand the polarization in orders of the perturbation. [Pg.254]

Adsorbates can physisorb onto a surface into a shallow potential well, typically 0.25 eV or less [25]. In physisorption, or physical adsorption, the electronic structure of the system is barely perturbed by the interaction, and the physisorbed species are held onto a surface by weak van der Waals forces. This attractive force is due to charge fiuctuations in the surface and adsorbed molecules, such as mutually induced dipole moments. Because of the weak nature of this interaction, the equilibrium distance at which physisorbed molecules reside above a surface is relatively large, of the order of 3 A or so. Physisorbed species can be induced to remain adsorbed for a long period of time if the sample temperature is held sufficiently low. Thus, most studies of physisorption are carried out with the sample cooled by liquid nitrogen or helium. [Pg.294]

When, for a one-component system, one of the two phases in equilibrium is a sufficiently dilute gas, i.e. is at a pressure well below 1 atm, one can obtain a very usefiil approximate equation from equation (A2.1.52). The molar volume of the gas is at least two orders of magnitude larger than that of the liquid or solid, and is very nearly an ideal gas. Then one can write... [Pg.353]

The principle of tire unattainability of absolute zero in no way limits one s ingenuity in trying to obtain lower and lower thennodynamic temperatures. The third law, in its statistical interpretation, essentially asserts that the ground quantum level of a system is ultimately non-degenerate, that some energy difference As must exist between states, so that at equilibrium at 0 K the system is certainly in that non-degenerate ground state with zero entropy. However, the As may be very small and temperatures of the order of As/Zr (where k is the Boltzmaim constant, the gas constant per molecule) may be obtainable. [Pg.373]

Oyy/Ais of the order of hT, as is Since a macroscopic system described by themiodynamics probably has at least about 10 molecules, the uncertainty, i.e. the typical fluctuation, of a measured thennodynamic quantity must be of the order of 10 times that quantity, orders of magnitude below the precision of any current experimental measurement. Consequently we may describe thennodynamic laws and equations as exact . [Pg.376]

Macroscopic systems contain a large number, N, of microscopic constituents. Typically A is of the order of... [Pg.378]

Wlien = N/2, the value of g is decreased by a factor of e from its maximum atm = 0. Thus the fractional widtii of the distribution is AOr/A i M/jV)7 For A 10 the fractional width is of the order of 10 It is the sharply peaked behaviour of the degeneracy fiinctions that leads to the prediction that the thennodynamic properties of macroscopic systems are well defined. [Pg.380]


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See also in sourсe #XX -- [ Pg.168 ]




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Experimental Determination of Reaction Order Simple Systems

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Further Examples of Simple, First-Order Spin Systems

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Order of a system

Order systems

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Response of higher-order systems

Systems of First-Order Ordinary Differential Equations

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Systems of higher order

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