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Simple approach

It is immediately seen that a solution of the set of equations is AG(i) = Q i. Further, [Pg.480]


Unfortunately, this simple approach is not plausible numerically. The integral, as presented, will not converge, even for short times. The problem is that even trajectories which are wild , i.e. highly fluctuating, contribute. [Pg.2314]

The examples of modelling discussed in section C2.5.2 and section C2.5.3 are meant to illustrate tlie ideas behind tlie tlieoretical and computational approaches to protein folding. It should be borne in mind tliat we have discussed only a very limited aspect of tlie rich field of protein folding. The computations described in section C2.5.3 can be carried out easily on a desktop computer. Such an exercise is, perhaps, tlie best of way of appreciating tlie simple approach to get at tlie principles tliat govern tlie folding of proteins. [Pg.2659]

To know simple approaches to quantify chemical reactivity... [Pg.169]

Simple Approaches to Quantifying Chemical Reactivity 3.4.2.1 Frontier Molecular Orbital Theory... [Pg.179]

L. iitortunately, this simple approach does not work well, but Becke has proposed a strategy which does seem to have much promise [Becke 1993a, b]. In his approach the exchange-correlation energy Exc is written in the following form ... [Pg.155]

The design of a collaborative test must provide the additional information needed to separate the effect of random error from that due to systematic errors introduced by the analysts. One simple approach, which is accepted by the Association of Official Analytical Chemists, is to have each analyst analyze two samples, X and Y, that are similar in both matrix and concentration of analyte. The results obtained by each analyst are plotted as a single point on a two-sample chart, using the result for one sample as the x-coordinate and the value for the other sample as the -coordinate. ... [Pg.688]

There is, however, only a limited quantity of by-product power available, and for large process operations the demand for power is usually far greater than the simple steam cycle can produce. Many steam system design decisions fall back to the question of how to raise the ratio of by-product power to process heat. One simple approach is to limit the turbines that are used to extract power to large sizes, where high efficiency can be obtained. [Pg.224]

Analysis and reporting of results, including a conformation run. The analysis of results should be transparent. Simple approaches should be used where possible to build confidence and provide clarity. [Pg.309]

The most straightforward approach is to assume that the field charging and diffusion charging are independent processes i.e., particle charge can be presented as a sum of charges due to field (s ) and diffusion (sj) charging. Another simple approach to estimating the combined effect is... [Pg.1225]

We concentrate here on open loop cooling in which compressor air mixes with the mainstream after cooling the blade row, the system most widely used in gas turbine plants (but note that a brief reference to closed loop. steam cooling in combined cycles is made later, in Chapter 7). For a gas turbine blade row, such as the stationary entry nozzle guide vane row where most of the cooling is required, the approach first described here (called the simple approach) involves the following ... [Pg.60]

Young and Wilcock [7] have recently provided an alternative to this simple approach. They also follow step (a), but rather than obtaining as in (b) they determine the constituent entropy increa.ses (due to the various irreversible thermal and mixing effects). Essentially, they determine the downstream state from the properties To and the entropy. v, rather than T), and po- This approach is particularly convenient if the rational efficiency of the plant is sought. The lost work or the irreversibility ( f = "lay be subtracted... [Pg.60]

Here we first describe the simple approach, assuming that ip is known, and describe how /),) and To downstream of the cooled row are obtained (steps (a) and (b) above). We then briefly describe the YoungAVilcock approach which leads to the determination and summation of the component entropy increa.ses, again for a given ip. [Pg.60]

In the simple approach, the change po due to Q (the first term in Eiq. (4.42)) is usually ignored for both streams. The change of po due to frictional effects in the mainstream flow is usually included in the basic polytropic efficiency (rjp) of the uncooled flow, so that... [Pg.62]

The simple approach described before involves approximations, particularly to obtain the stagnation pressure loss. The full determination of pf) m (7 o)5m from the various equations given above can lead to an approximation for the downstream entropy (.vsni). using the Gibbs relation applied between stagnation states. [Pg.64]

A relatively simple approach suggests itself if the interfaces are known to be almost flat. In that case, the interface position can be described by a single-valued function z(x,y), where (A,y) are cartesian coordinates on a flat parallel reference plane. The functional (21) can be approximated by... [Pg.668]

Determine the initial strengths of the charges. A quick and simple approach to estimation of initial strengths of the charges expressing the potential explosive power within the vapor cloud is to use the following safe and conservative approach ... [Pg.270]

A ratlier simple approach is to superimpose the settling velocity of the particle on the initial point of discharge in the following manner ... [Pg.378]

A simple approach for the formation of 2-substituted 3,4-dihydro-2H-pyrans, which are useful precursors for natural products such as optically active carbohydrates, is the catalytic enantioselective cycloaddition reaction of a,/ -unsaturated carbonyl compounds with electron-rich alkenes. This is an inverse electron-demand cycloaddition reaction which is controlled by a dominant interaction between the LUMO of the 1-oxa-1,3-butadiene and the HOMO of the alkene (Scheme 4.2, right). This is usually a concerted non-synchronous reaction with retention of the configuration of the die-nophile and results in normally high regioselectivity, which in the presence of Lewis acids is improved and, furthermore, also increases the reaction rate. [Pg.178]

A SIMPLE APPROACH TO THE ENERGETICS OF SURFACE DEFECTS IN TRANSITION METALS... [Pg.371]

Grolmes, M. A., A Simple Approach to Transient Two-Phase Level Swell, Multi-Phase Flow and Heat Transfer III. Part A Fundamentals. Proceedings of the Third Multi-Phase Flow and Heat Transfer Symposium—Workshop, Miami Beach, FL, April 18-20, 1983. [Pg.545]

The ideal gas law offers a simple approach to the experimental determination of the molar mass of a gas. Indeed, this approach can be applied to volatile liquids like acetone (Example 5.4). All you need to know is the mass of a sample confined to a container of fixed volume at a particular temperature and pressure. [Pg.109]

There are several ways to determine Kb of a weak acid. A simple approach involves measuring [H+] or pH in a solution prepared by dissolving a known amount of the weak acid to form a given volume of solution. [Pg.362]

The cyclotetramerization of suitable monopyrroles is the most simple approach to prepare porphyrins and it has been used in the synthesis of numerous porphyrin structures. But this method can only be used satisfactorily if the pyrroles 1 and 2 bear identical /i-substituents (R = R), otherwise the cyclotetramerization leads to a statistical mixture of four possible constitutional isomers. [Pg.581]

The above rate equation is in agreement with that reported by Madhav and Ching [3]. Tliis rapid equilibrium treatment is a simple approach that allows the transformations of all complexes in terms of [E, [5], Kls and Kjp, which only deal with equilibrium expressions for the binding of the substrate to the enzyme. In the absence of inhibition, the enzyme kinetics are reduced to the simplest Michaelis-Menten model, as shown in Figure 5.21. The rate equation for the Michaelis-Menten model is given in ordinary textbooks and is as follows 11... [Pg.137]

This simple approach means that HW heating and LP steam heating systems generally are treated in like manner, and often no specific oxygen scavenger is employed. Thus, the potential for significant oxygen corrosion commonly exists. [Pg.178]

The rationale for these simple approaches to water treatment is the argument that these kinds of systems have minimal requirements for MU water and are therefore subject to a reduced level of risk. In practice, the validity of this argument is suspect but is difficult to prove because totalizing water meters are seldom installed on the MU water line. [Pg.178]

The Alexander model allows a simple approach to this problem. Within this model, each tethered chain is, in effect, confined within a cylindrical capillary of diameter d. Combining Eq. 5 and 7, we can express the stretching energy as ... [Pg.64]

Alternative simple approaches to approximations for the exponential integral exploit the linearity of the log P(t/) against U relation over short ranges [533,542,543]... [Pg.103]

If the rate of a reaction is governed by the encounter frequency, it is said to be diffusion-controlled. This frequency imposes an upper limit on the rate of reaction that can be evaluated by the use of Fick s laws of diffusion. The mathematical expression of this phenomenon was first presented by von Smoluchowski.2 We shall adopt a simple approach,3,4 although more rigorous derivations have been given.5... [Pg.199]

Strecker153 reported in 1910 that the reaction of thionyl chloride with two equivalents of phenylmagnesium bromide or benzylmagnesium bromide afforded diphenyl or dibenzyl sulphoxides, respectively (equation 49 Table 8). The corresponding sulphides are formed as by-products of this reaction. Recently, other sulphoxides were prepared by this procedure154,155. It should be pointed out that this rather simple approach to the synthesis of symmetrical sulphoxides has not yet found wider application. [Pg.257]


See other pages where Simple approach is mentioned: [Pg.1509]    [Pg.136]    [Pg.370]    [Pg.483]    [Pg.352]    [Pg.65]    [Pg.100]    [Pg.187]    [Pg.1198]    [Pg.61]    [Pg.181]    [Pg.78]    [Pg.1052]    [Pg.459]    [Pg.310]    [Pg.533]    [Pg.88]   
See also in sourсe #XX -- [ Pg.342 , Pg.362 ]




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