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Efficiency equation

For sieve or valve plates, h = h , outlet weir height. For bubble-cap plates, h = height of static seal. Tbe original references present vaH-dations against laboratoiy and small-commercial-column data. Modifications of tbe efficiency equation for absorption-stripping are also included. [Pg.1381]

The maximum possible efficiency at which a heat engine can work is defined by the Carnot efficiency equation E = (T2—Tl)/T2, where E is the efficiency of the heat engine, T1 is the temperature of the cold... [Pg.888]

Referenced to 806 data points for binary systems. Equation 8-70A gives absolute deviation of 13.2%, which is about as accurate, or perhaps more so, than other efficiency equations. Equation 8-70B uses the same data and has an absolute average deviation of 10.6%. See Example 8-13 for identification of dimensionless groups. [Pg.42]

Despite their flaws, batch processes have stood the test of time for a number of reasons, the most important of which is the flexibihty it brings to the manufacturer in terms of the range of products that the plant can produce, the feedstocks used to produce them, and the speed at which they can be brought to market with very limited information on physical properties, reaction kinetics, and so on (very few, if any, Michelin-starred chefs have ever measured the rheology or kinetics of their latest culinary creation). This flexibility, however, has a price which comes in the form of lower efficiencies in terms of production, energy, labor, and so on, and ultimately efficiency equates to cost However, one should never underestimate the pull of flexibility particularly, as discussed earlier in the examples of fermentation, where control of important parameters is difficult to achieve. [Pg.314]

In comparison the theoretical efficiency of a conventional combustion engine is limited by the Camot-cycle efficiency. This efficiency (Equation 6.5) is a function of the operating temperature (T2) and the temperature of the surroundings (Ti). [Pg.179]

As noted above, formation of a furan [4 + 3]-cycloadduct during irradiation of a 4-pyrone was advanced as evidence for the zwitterionic intermediate. This process can be moderately efficient (equation 4)68, and can be envisioned as an approach to substituted cyclooctanoids. Besides the formation of three new carbon-carbon bonds, an additional attractive feature is the complete diastereoselectivity, arising from a compact [4 + 3]-cycloaddition transition state with approach from the face opposite the epoxide. However, the generality of the intermolecular reaction is limited, as competing [2 + 21-photodimerization, solvent trapping and rearrangement often predominate58. [Pg.293]

Alkenyl trifluoromethanesulphonates (enol triflates) undergo Heck coupling with alkenes efficiently (equation 123)209a 215. This reaction is a useful variation of the use of vinyl halides not only because they are easy to prepare from the corresponding carbonyl compounds, but also because yields are good, and the stereochemistry of the triflate is largely maintained. [Pg.433]

Overall, the most effective factor in Equation 5.20 is the particle size. The smaller the particle size, the higher the column efficiency. Equations 5.13, 5.15, and 5.18 are depicted in Figure 5.6 against flow velocity as A, B, and C, respectively. The band spreading is thus influenced by Equation 5.15 at a low flow rate. The band spreading is influenced by Equations 5.18 and 5.19 at a high flow rate. For gas chromatography curve D is obtained. [Pg.106]

The deprotonation of A-Boc-piperidine (159), giving substituted piperidines such as 160, proceeds with much lower efficiency (equation 36)" " . The main side reaction is the attack of i-BuLi at the Boc-group. The observation of slower and less selective lithiation is supported by quantum-chemical studies. ... [Pg.1087]

Graphite felt anode modihed by spiro-type chiral A-oxyl mediated enantioselective oxidation of primary alcohols proceeded with excellent efficiencies (equation 26)". ... [Pg.509]

Functionalized zinc carbenoids have been prepared from diiodoalkanes and diethylzinc and used in stereoselective transformations, but their use is limited by the availability of the diiodoalkane" ° and the stability of the resulting zinc carbenoid. Alternatively, the reaction of a diazoalkane with Znl2 can be used to access complex zinc carbenoids, but with modest efficiency (equation 9) . ... [Pg.241]

Consider the deciding-doing model of team efficiency [Equation (9.2)] and apply it to a team project you have worked on. Specifically, tally the total time spent in meetings versus the total time spent working on getting the project done. Calculate the optimal team size. Consider whether your team is larger or smaller than that number. [Pg.150]

In general, the chemistry of fluoro-l,3,5-triazines resembles that of the chloro derivatives, and therefore will not be discussed in detail. There is evidence that cyanuric fluoride is less reactive than cyanuric chloride in reaction with aniline (76CCC3378). Chambers et al. have reported the isolation of a stable anion cr- complex from the reaction of cyanuric fluoride and cesium fluoride (equation 32) (77JCS(Pl)l605). Such species are believed to be intermediates in the formation of (68) from cyanuric fluoride and perfluoropropene (equation 33). Olah et al. have shown that cyanuric fluoride deoxygenates sulfoxides efficiently (equation 34) (80S221). [Pg.486]

Intramolecular addition-oxidation with reactive carbanions is generally successful most of the examples involve cyano-stabilized carbanions. Formation of a six-membered fused ring (46) is efficient (equation 42), but five-membered fused ring formation is not.17 The only addition-oxidation product is a cyclic dimer, the [3.3]metacyclophane (47).17... [Pg.540]

Lewis acid-catalyzed stereoselective addition of crotylsilanes to chiral 74 has been studied in detail111,112. The presence of the chiral auxiliary at C2 (e.g. p-tolylsulfinyl or menthoxy carbonyl group) induces the diastereofacially selective addition of cyclopentenones with crotylsilanes. Thus, ( )-crotylsilane favors the erythro product, whilst (Z)-isomer favors the threo product. High enantioselectivity is observed in both reactions (equation 48). In a similar manner, conjugated addition of allylsilane to 75 proceeds with high efficiency (equation 49)113. Interestingly, the yield and enantiomeric excess of the product is dependent on the amount of TiCL used and the best selectivity... [Pg.1812]

Important Note Bubble cap HHD factor is equivalent to the DPntAYi dry pressure drop of valve trays. The bubble cap tray total pressure drop factor DPTRay is equivalent to the HDC2 factor of valve-type trays. You may therefore substitute these bubble cap values in the ETF efficiency equations as given for valve trays to determine bubble cap tray efficiency. [Pg.104]

However, neither Cul nor CuBr2 activated by ClSi(CH3)3 and HMPA is useful as a catalyst for conjugate addition of CH3MgBr to a,(5-unsaturated esters. Even the CH3Cu BF3 complex is not useful in this reaction. Surprisingly, the Cu(II) complex 1 is remarkably efficient (equation I). [Pg.37]

The definition of the grade efficiency (Equation 9) is similar to the total efficiency definition, but it applies only to a given bioparticle size. Figure 11.5 shows a typical grade efficiency curve ... [Pg.277]

Equation (17), obtained from Equation (10), shows that it is possible to estimate the total efficiency of cell separation when the curves of grade efficiency and feed size distribution are known. Based on Equations (16) and (17), it is possible to obtain a similar result for the reduced total efficiency (Equation 18). [Pg.278]

Cu(OTf)2 (2mol%) is required (Equation (110)).183 The nature of the copper salt strongly influences the enantio-selectivity, and copper carboxylates proved to be especially efficient (Equation (lll)).184b It has been applied for an enantioselective synthesis of prostaglandin E methyl ester (Equation (112)),185 and can be used for the performance of a highly regiodivergent and catalytic parallel kinetic resolution.186... [Pg.111]

In an internal combustion engine, the efficiency of the engine is given by a Carnot efficiency equation ... [Pg.36]

Express the collection efficiency in terms of dp in micrometers. The efficiency equation set out in step 1 is for dp in feet. To adapt it for dp in micrometers, note that there are 304,800 pm in a... [Pg.503]

In equilibrium-stage models, the compositions of the leaving streams are related through the assumption that they are in equilibrium (or by use of an efficiency equation). It is important to recognize that efficiencies are not used in a nonequilibrium model they may, however, be calculated from the results obtained by solving the model equations. [Pg.49]

Other measures of efficiency are derived from the experimental RTD, which is characterized at least approximately by the variance This quantity is zero for plug flow and unity for complete mixing, and thus affords natural bounds to an efficiency equated to the variance. It is possible, however, for the variance to fall out of the range (0,1) when stagnancy or bypassing occurs. [Pg.1839]

N. Single Spherical Collector Efficiencies. Four collection mechanisms are considered in the present analysis inertial impaction, interception. Brownian movement and Coulombic forces. Although in our previous analysis the electrical forces were considered to be of the induced nature (13), there is evidence that it is the Coulombic forces which dominate the electrical interactions between the particle and collector (, ], 22). Taking the net effect as the simple summation of each collection mechanism results in the single spherical collector efficiency equation. [Pg.82]

Although this method is convenient in the laboratory, t- and i-BnLi are somewhat expensive and shonld be handled carefnlly, especially in a large scale. A more practical method for the synthesis of ynolates is the rednctive lithiation method. The dibromo esters 43 are treated with lithinm naphthalenide to give the ynolates 44 in good yield. Naphthalene-catalyzed reductive lithiation of the dibromo esters can also be performed, providing the ynolates more efficiently (equation 17) . [Pg.747]

Variations on the hydrazulene skeleton have been approached via the Pauson-Khand reaction, several with high regio- and diastereo-selectivity. Pauson s cycloadditions of cycloheptene provided the Brst entries but were limited in scope and efficiency (equation 39).2° Several synthetic equivalents of cyclohep-tenes displaying greater reactivity include 8-oxa- and 8-aza-bicyclo[3.2.1]oct-6-enes (equations 48 and... [Pg.1051]


See other pages where Efficiency equation is mentioned: [Pg.42]    [Pg.365]    [Pg.1429]    [Pg.1273]    [Pg.195]    [Pg.735]    [Pg.823]    [Pg.403]    [Pg.169]    [Pg.360]    [Pg.133]    [Pg.393]    [Pg.73]    [Pg.145]    [Pg.114]    [Pg.260]    [Pg.42]    [Pg.1252]    [Pg.3329]    [Pg.365]   
See also in sourсe #XX -- [ Pg.341 ]




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