Rate, meaning

Relative rate meaning, here, simply the ratio of nitro-alkylbenzene to nitrobenzene, multiplied by the initial ratio of alkylbenzene to benzene. This is not precisely the same as the ratio of rate constants for nitration. ... 

Fits some, but not all, data. Low mass transfer rate. = mean molecular weight of dispersed phase tf= formation time of drop. k[, i = mean dispersed liquid phase M.T. coefficient kmole/[s - m" (mole fraction)]. 

The GIDEP Reliability-maintainability Data Bank (RMDB) has failure rates, failure modes, replacement rates, mean time between failure (MTBF) and mean time to repair (MTTR) on components, equipment, subsystems and systems. The RMDB includes field experience data, laboratory accelerated life test data, reliability and maintainability demonstration test results. The... 

FIGURE 5.33 (a) Excretion rate (means and standard deviations of the means) of ethyle-... 

The NERC GADS ten-year review report for 1971-1980 on equipment availability presents statistical data sets on the performance of major types of electrical power generating units. Cumulative and unit.-year averages are calculated on such quantities as service hours, available hours, scheduled outage rate, mean time between full forced outages, shutdown because of economic reasons, and probability of outage. The number of start demands and successful starts are included. 

Table I. Photosynthetic rates (mean standard deviation n=3) for samples taken from three different habitats and incubated for 4 hours under the four experimental conditions described in the text (Amb = ambient UV Exc =...

More recent reports conclude that early CEA after a nondisabling ischemic stroke can be performed with perioperative mortality and stroke rates comparable to those of delayed CEA. In a subgroup analysis by the North American Symptomatic Carotid Endarterectomy Trial (NASCET) investigators, 42 patients who underwent early CEA (<30 days after stroke) were compared with 58 patients who underwent delayed CEA (>30 days), and no overall difference was demonstrated in the perioperative stroke rate (4.8% vs. 5.2%). Another recent prospective randomized study of 86 patients showed no difference in either perioperative stroke (2% in both groups) or survival rates (mean 23 months follow-up) between patients randomized to early or delayed CEA. ... 

In general, a preparation of mixed monolayer can be realized by either a kinetic control or a thermodynamic control (Figure 1, left). Kinetic control is based on a suggestion that for an initial deposition step the desorption rate is ignorable in comparison with the adsorption rate. In this case, the concentration ratio of the adsorbed species A and B on the surface corresponds to the ratio of products of their adsorption rate constant ( a or b) and concentration (Ca or Cb) A aCa/A bC b. The validity of the initial assumption on low desorption rate means that the total surface coverage obtained under kinetic control is essentially lower than 100%. This non-complete coverage does not disturb most of optical applications of the... 

Instant coffee beverages are markedly different from coffee prepared from roast and ground coffee directly. As has already been described in Section III.E, instant coffees contain extra water-soluble carbohydrates obtained from hydrolyzed complex carbohydrates. The high extraction rate means that about 100 cups of instant coffee can be prepared from 1 lb of coffee, compared with 40 to 50 cups per pound of normally brewed coffee. 

Hemodynamics (blood pressure, heart rate, mean arterial pressure, etc.)... 

First, the authors examined the distribution of total PCL-R scores using special probability graph paper (Harding, 1949). This method is a predecessor to mixture modeling it allows for estimation of taxon base rate, means, and standard deviations of latent distributions. The procedure suggested the presence of two latent distributions, with the hitmax at the PCL-R total score of 18. Harding s method is appropriate conceptually and simple computationally, but it became obsolete with the advent of powerful computers. On the other hand, there is no reason to believe that it was grossly inaccurate in this study. 

Obviously one of the important economic requirements for electroplating industry is that as much material is plated in as short a time as possible. Therefore industrially the process is run at high currents for maximum discharge rate (Faraday s first law). However higher discharge rates mean that the surface concentration of the ions at the... 

Table 3.2 Rouse rates mean-square monomer length monomeric...

In contrast, at [H+] > 0.1 M, the same reaction results in two or three new EPR signals (glso 1.974, 1.971, and 1.966) in addition to the one already mentioned feso= 1.979).68,75 These EPR signals turn out to be consistent with six-coordinated oxo-Cr(V) species. In this situation, the relative intensity of the EPR signal is pH dependent but is independent of the aldohexose/Cr(VI) ratio. In fact, six-coordinated species are dominant at [H+] > 0.75 M. In addition, both species [six- and five-coordinated oxo-Cr(V) complexes] decay at the same rate, meaning that they are in a rapid equilibrium. Scheme 5 shows the complexation chemistry and the observed Cr(V)-sugar redox processes. 

The reaction of 2-deoxy-D-arabino-hexose (26) and Cr(VI) results in the formation of two oxo-Cr(V) species with giso= 1.9781 and 1.9754 in 2 6 ratio, independently of the pH and concentration of 26.85The two species disappear at comparable rates, meaning that these Cr(V) intermediates are in rapid equilibrium compared to the timescale of their subsequent reduction to Cr(III). The analysis of the EPR parameters indicates that the signals can be assigned to Cr(V)-bis- and monochelates formed with the substrate, namely [Cr0(03,04-26)(01-26)(H20)] and [Cr0(01-26)(H20)3]2+.50... 

The decrease in film burn-out heat flux with increasing mass velocity of flow at constant quality has been explained by Lacey et al. in the following way. At constant quality, increasing total mass flow rate means increasing mass flow of vapor as well as liquid. It has been shown that above certain vapor rates increased liquid rates do not mean thicker liquid layers, because the increased flow is carried as entrained spray in the vapor. In fact, the higher vapor velocity, combined with a heat flux, might be expected to lead to easy disruption of the film with consequent burn-out, which seems to be what actually occurs at a constant steam mass velocity over very wide ranges of conditions—that is, the critical burn-out steam quality is inversely proportional to the total mass flow rate. 

Kinetic data are frequently acquired in continuous reactors rather than batch reactors. These data permit one to determine whether a process has come to steady state and to examine activation and deactivation processes. These data are analyzed in a similar fashion to that discussed previously for the batch reactor, but now the process variables such as reactant flow rate (mean reactor residence time) are varied, and the composition will not be a function of time after the reactor has come to steady state. Steady-state reactors can be used to obtain rates in a differential mode by maintaining conversions small. In this configuration it is particularly straightforward to vary parameters individually to find rates. One must of course wait until the reactor has come to steady state after any changes in feed or process conditions. 

With the acceptance of the atomic view of the world - accompanied by the necessity to explain reactions in extremely dilute gases (where the continuum theory fails) - the kinetic gas theory was developed. Using this it is possible not only to derive the ideal gas law in another manner but also to calculate many other quantities involved with the kinetics of gases - such as collision rates, mean free path lengths, monolayer formation time. 

The secondary variables, such as shear rate, mean residence time, power consumption, throughput rate, etc., are expressed as a function of the primary variables. For example, the shear rate (or material displacement rate) in the screw channel is a function of the primary variables D, N, and H... 

Overall rate means the expression of the rate of the process in terms of the bulk liquid or gas-phase concentration. The overall rate can be expressed in terms of the bulk liquid concentration for continuous and semibatch operation. However, the overall rate can be expressed in terms of bulk gas-phase concentration only in the case of a semibatch operation, i.e. continuous flow of gas and batch liquid. Both cases are analyzed in detail in the following sections. 

The first term is represents the motion of the lower left-hand comer and the second term, the linear expansion, indicates how the circumferential velocity changes over the length of the element, dr. Since the circumferential velocity w(r) is generally not a linear function of r, there is a relative speedup or slowdown of the right-hand comer relative to the linear rate, meaning that there is shearing as evidenced by da 0 and ds 0. The distance ds... 

Explain what each of the three numbered hazard ratings means for 37 wt% HC1 in Figure 2-2. 

The two most important classes of radical initiators are azo-compounds and peroxides (Fig. 10.1). The most commonly used azo-initiators are 2,2/-azobis(isobutyronitrile) (AIBN) and l,l/-azobis(cyclohexane-l-carbonitrile) (ACN). The shorter half-life of AIBN ( ti/2 = 1.24 h at 80°C in benzene) has led to international shipping restrictions and ACN (ti/2 = 29.61 h under the same conditions [l])isbecominganincreasinglyvaluablereplace-ment. As explained in Section 10.4, however, this appreciable difference in decomposition rate means that ACN cannot replace AIBN as an initiator for all radical reactions. Furthermore, AIBN is soluble in a wider range of solvents, polar as well as non-polar (including alcohols, acetonitrile and benzene), compared with ACN which is restricted to use in nonpolar solvents, such as benzene, toluene and cyclohexane. 

The flexibility this approach brings when applied to royalty rates means that it is possible to institute a differential approach to rates depending upon performance. Thresholds for performance can sit on either side of the product s true sales forecast, allowing the provision for a step up in the royalty rate or a step down according to the desired reward structure. In fact a series of steps can be built into a tiered structure, which can give a steady improvement or a tailing off, and these modifications can act as an incentive for a company to sell... 

For cases where the secondary reaction plays a role (class 5), or if the gas release rate must be checked (classes 2 or 4), the heat release rate can be calculated from the thermal stability tests (DSC or Calvet calorimeter). Secondary reactions are often characterized using the concept of Time to Maximum Rate under adiabatic conditions (TMRad). A long time to maximum rate means that the time available to take risk-reducing measures is sufficient. However, a short time means that the... 

---