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Rate rational

The order in which PEH, AP, and MPC formed was determined from the time dependence of product accumulation rate rations at t 0. The variation of these rations with time was evaluated by graphic differentiation [17]. [Pg.197]

Rating programs Rational design Rational drug discovery Rauwolfia serpentina Rauwolscine [131-03-3]... [Pg.841]

Product standards may stipulate performance characteristics, dimensions, quaUty factors, methods of measurement, and tolerances and safety, health, and environmental protection specifications. These are introduced principally to provide for interchangeabiUty and reduction of variety. The latter procedure is referred to as rationalization of the product offering, ie, designation of sizes, ratings, etc, for the attribute range covered and the steps within the range. The designated steps may foUow a modular format or a preferred number sequence. [Pg.17]

To avoid confusion, several researchers have incorporated therapeutic intention into the definition of controlled release (4—7). Thus, controUed-release pharmaceuticals release dmgs in vivo according to a predictable, therapeutically rational, programmed rate to achieve the optimal dmg concentration in the minimal time (4). Specification by release rate complements specification by quantity jointly considered, they fix the duration of dmg release. Therefore, the dmg s duration of action can become a design property of a controlled release dosage form rather than an inherent pharmacokinetic property of the dmg molecule. [Pg.140]

Plate-Column Capacity The maximum allowable capacity of a plate for handling gas and liquid flow is of primaiy importance because it fixes the minimum possible diameter of the column. For a constant hquid rate, increasing the gas rate results eventually in excessive entrainment and flooding. At the flood point it is difficult to obtain net downward flow of hquid, and any liquid fed to the column is carried out with the overheaa gas. Furthermore, the column inven-toiy of hquid increases, pressure drop across the column becomes quite large, and control becomes difficult. Rational design caUs for operation at a safe margin below this maximum aUowable condition. [Pg.1371]

For certain simplified cases it is possible to calculate directly the number of stages required to attain a desired product composition for a given set of feed conditions. For example, if equilibrium is attained in all stages and if the underflow mass rate is constant, both the equilibrium and operating lines on a modified McCabe-Thiele diagram are straight, and it is possible to calculate direc tly the number of ideal stages required to accommodate arw rational set of terminal flows and compositions (McCabe, Smith, and Harriott, op. cit.) ... [Pg.1677]

Significant distinction in rate constants of MDASA and TPASA oxidation reactions by periodate ions at the presence of individual catalysts allow to use them for differential determination of platinum metals in complex mixtures. The range of concentration rations iridium (IV) rhodium (III) is determined where sinergetic effect of concentration of one catalyst on the rate of oxidation MDASA and TPASA by periodate ions at the presence of another is not observed. Optimal conditions of iridium (IV) and rhodium (III) determination are established at theirs simultaneous presence. Indicative oxidation reactions of MDASA and TPASA are applied to differential determination of iridium (IV) and rhodium (III) in artificial mixtures and a complex industrial sample by the method of the proportional equations. [Pg.37]

Describe the nature of the process measured by each of these rate constants, and devise a mechanism which includes each of these processes. Rationalize the order of the rates > ex > K-... [Pg.338]

Give a rationalization for the form of this correlation equation. What information does it give regarding involvement of the Ari ring in the rate-determining step ... [Pg.403]

A computer program is provided for ease of calculation and efficient use of the standard. This rational method of assessing hot environments allows identification of the relative importance of different components of the thermal environment, and hence can be used in environmental design. The WBGT index is an empirical index, and it cannot be used to analyze the influence of the individual parameters. The required sweat rate (SW. ) has this capability, but lack of data may make it difficult to estimate the benefits of protective clothing. [Pg.385]

The anomalous iodoacetamide-fluoride reaction violates this rule, in that a less stable -halonium complex (18) must be involved, which then opens to (19) in the Markownikoff sense. This has been rationalized in the following way estimates of nonbonded destabilizing interactions in the possible products suggest that the actual product (16) is more stable than the alternative 6)5-fluoro-5a-iodo compound, so the reaction may be subject to a measure of thermodynamic control in the final attack of fluoride ion on the iodonium intermediate. To permit this, the a- and -iodonium complexes would have to exist in equilibrium with the original olefin, product formation being determined by a relatively high rate of attack upon the minor proportion of the less stable )9-iodonium ion. [Pg.458]

Repeat your analysis for Z,Z-hexa-2,4-diene, and again calculate the energy to twist the diene into the same conformation as seen in the Diels-Alder transition state (Z,Z-hexa-2,4-diene+TCNE). Compare the two twisting energies , and rationalize the observed relative rates for the two cycloaddition reactions. [Pg.277]

During the early development of the Jacobsen-Katsuki epoxidation reaetion, it was elear that trans-disubstituted olefins were very poor substrates (slow reaetion rates, low enantioseleetivity) eompared to cis-disubstituted olefins. The side-on approaeh model originally proposed by Groves for porphyrin epoxidation systems was used to rationalize the differenees observed in the epoxidation of the cis and trans-disubstituted elasses (Seheme 1.4.7). ... [Pg.37]


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See also in sourсe #XX -- [ Pg.154 ]




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