First-order phase

First of all the term stress-induced crystallization includes crystallization occuring at any extensions or deformations both large and small (in the latter case, ECC are not formed and an ordinary oriented sample is obtained). In contrast, orientational crystallization is a crystallization that occurs at melt extensions corresponding to fi > when chains are considerably extended prior to crystallization and the formation of an intermediate oriented phase is followed by crystallization from the preoriented state. Hence, orientational crystallization proceeds in two steps the first step is the transition of the isotropic melt into the nematic phase (first-order transition of the order-disorder type) and the second involves crystallization with the formation of ECC from the nematic phase (second- or higher-order transition not related to the change in the symmetry elements of the system). 

Concentration of ethanol in the compound surface layer in equilibrium with the gas phase First-order reaction constant for the silanization reaction Volumetric flow rate of ethanol from the compound to the gas phase Time... 

Kinetics First-order First-order after initial enzyme induction phase First-order First-order First-order... 

Consider a liquid-phase, first-order reaction A C, occurring in a reactor of volume V, with a specified down-time, td. The reactor initially contains 5 moles of pure A. Determine the reaction time which maximizes Pr(C), given kA = 0.021 min-1, and td = 30 min and calculate the maximum value of Pr(C). 

Reacting liquid-phase First-order in gas reactant and constant gas-phase concentration The overall rate is exactly the same as in the nonreacting liquid ... 

Pure component in gas phase and saturated liquid phase First-order kinetics in A In this case, the gas phase is a pure component A (CAG is constant) and the liquid phase is considered to be saturated with A (C is constant). Furthermore, the intrinsic rate is considered to be of fust order with respect to A -rm = /cmCAS, per unit mass of catalyst. Under these conditions, the material balances for the gas component A in the gas and liquid phases (eqs. (3.365) and (3.367)) are not needed CAL is constant and equal to CAl q = CAG/HA. The same analysis is valid for reactions of fu st order for both components, if Cbl -> > Cal and thus CBS = const (pseudo-first order) (Smith, 1981). Then (eq. (3.369))... 

Eq. (3) may be substituted into a general rate expression of the form dx/dt to give an expression of the form dq/dt (or power). For example, the general rate expression for a simple, solution phase, first-order, A -x process is given by Eq. (4). 

We begin by considering the simple chemistry of a liquid-phase, first-order, irreversible, exothermic reaction occurring in a batch reactor ... 

Example 7.6 Product B is produced in an isothermal tubular reactor where the following gas-phase, first-order chemical reactions take place ... 

Consider a liquid-phase, first-order reaction of the form A P + R in an isothermal cascade of CSTRs where only reactant A is fed to the system. Taking the inlet stream to the cascade as the reference stream and since only reactant A is fed, y o = 1- Using Eq. 8.2.3, the design equation for the nth CSTR is... 

Example 10.2 The liquid-phase, first-order reaction... 

Pure component in gas phase and saturated liquid phase First-order kinetics in A In tliis case, tire gas phase is a pme component A (C q is constant) and the hquid phase is considered to be saUirated witli A (C is constant). Fui theimore, the intrinsic rate is considered to be of fust order with respect to A -r = per unit mass of catalyst. Under these... 

Consider the continuous stirred tank reactor (CSTR) with entering fluid having concentration Cao snd flow rate F, as shown in the figure below. A liguid-phase first-order reaction takes place A- B. 

Analysis For this irreversible liquid-phase first order reaction (i.e., = tC )... 

The trickle-bed catalytic reactor shown in Fig. 6.8 utilizes product recycle to obtain satisfactory operating conditions for temperature and conversion. Use of a high recycle rate eliminates the need for mechanical agitation. Concentrations of the single reactant and the product are measured at a point in the recycle line where the product stream is removed, A liquid phase first-order reaction is involved. 

The optically active and deuterium-labelled methylenecyclobutane (392) has been thermolysed at 332°C in the gas phase first-order rate constants for deuterium scrambling and racemization were obtained. That they are unequal, with the scrambling almost twice as fast as racemization, is sufficient evidence to exclude several mechanistic possibilities and to implicate, at least to some extent, a l,3rsigmatropic migration of carbon which is antarafacial with respect to the allylic group. The rearrangement of (393) to (394) has also... 

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