Effect on performance

The H2SO4 catalyst produces a high octane product of similar composition from either 2-butene or 1-butene. This fact suggests that the isomerization of 1-butene to 2-butene is more complete than in the HF system. Isobutylene produces a slightly lower product octane than do the / -butenes. The location of a methyl tert-huty ether [1634-04-4] (MTBE) process upstream of the H2SO4 alkylation unit has a favorable effect on performance because isobutylene is selectively removed from the alkylation feed. 

Primary Variables. The most obvious variables are those whose effects on performance are to be evaluated directiy these ate the variables that, most likely, created the need for the investigation in the first place. Such variables may be quantitative, such as catalyst concentration, temperature, or pressure, or they may be quaUtative, such as method of preparation, catalyst type, or batch of material. 

Quahtative variables can be broken down into two categories. The first consists of those variables whose specific effects ate to be compared directiy eg, comparison of the effect on performance of two proposed preparation methods or of three catalyst types. The requited number of conditions for such variables is generally evident. Such variables are sometimes referred to as fixed effects or Type I variables. 

To determine the effects on performance, costs, and time-scales... 

Wet steam erodes the ejector nozzle and interferes with performance by clogging the nozzle with water droplets [16]. The effect on performance is significant and is usually reflected in fluctuating vacuum. 

The distributor and packing are the heart of the performance of this equipment. Their proper selection entails an understanding of packing operational characteristics and the effect on performance of the points of significant physical difference between the various types. 

Table 12-16 (presented in the fan section of this chapter) indicates a more complete examination of the variables and their effects on performance of the rotating devices, such as centrifugal compressors and fans. 

As noted for experiment HGR-13, the deactivation rate increased significantly when the fresh feed space velocity was increased from 2000 to 3000/hr. During the period of 841-1058 hrs, the fresh feed space velocity was returned to 2000/hr and the CGR ratio was increased from — 3 1 to 9 1 to give a low deactivation rate of 0.0027%/mscf/lb. When the CGR ratio was returned to 3 1 at 1058-1760 hrs, the rate of catalyst deactivation increased to 0.0187%/mscf/lb. After 1760 hrs, the unit was shut down and put in standby condition under hydrogen. After the unit was restarted, the deactivation rate had increased greatly to 0.0821%/ mscf/lb which indicates that the increase in deactivation rate was associated with this particular shutdown. Since this experiment had previously undergone three unscheduled shutdowns at 215, 798, and 894 hrs with no adverse effect on performance, some unknown factor unique to the shutdown at 1760 hrs was responsible for the subsequent rapid decline in activity. 

Licht S, Tenne R, Flaisher H, Manassen J (1984) A pronounced cation effect on performance and stability of Cd- chalcogenide/polysulfide photoelectrochemical cells. J Electrochem Soc 131 950-951... 

The effectiveness of a number of crude oil dispersants, measured using a variety of evaluation procedures, indicates that temperature effects result from changing viscosity, dispersants are most effective at a salinity of approximately 40 ppt (parts per thousand), and concentration of dispersant is critical to effectiveness. The mixing time has little effect on performance, and a calibration procedure for laboratory dispersant effectiveness must include contact with water in a manner analogous to the extraction procedure otherwise, effectiveness may be inflated [587]. Compensation for the coloration produced by the dispersant alone is important only for some dispersants. 

Dodd et al.48 tested 17 moderately trained males for V02 max and time to exhaustion on a bicycle ergometer. Experimental trials involved the administration of 3- or 5-mg/kg caffeine 1 h prior to testing. Caffeine had no effect on exercise performance. Since nearly half of the subjects were caffeine naive (<25 mg/d), while the other half were caffeine tolerant (>310 mg/d), the researchers were able to conclude that even though caffeine had no significant effects on performance, it did produce a variety of physiologically significant effects (heart rate and expired ventilation volume) in the caffeine naive group. 

No neurobehavioral effects were seen in 288 randomly selected males who were occupationally exposed to lead as compared to 181 demographically similar controls (Ryan et al. 1987). The mean PbB level in the exposed workers was 40.1 pg/dL and that of the controls was 7.2 pg/dL. Nineteen tests of neuropsychological performance were conducted. The lead-exposed workers performed no differently from controls on all measures except psychomotor speed and manual dexterity. The authors discounted this difference due to the observation that conflicting results were obtained in two different tests of motor speed and manual dexterity and possible confounding effects of age. There was no evidence that history of previous very high exposure had any effect on performance. 

Illustrative performance properties for a "general purpose polycarbonate," and for the same resin modified with the additive formulations "700" (without PTFE) and "800" (with PTFE) are summarized in Table IV (adapted from reference 32). It is clear that the objective of minimal effect on performance properties has been attained for this system. It is evident that flame retardant effectiveness attained with minimal levels of additive can provide optimum solutions to the problem of decreasing flammability without sacrifice in performance properties. Work documented to date suggests that in depth studies of thermal degradation such as reported for aromatic sulfonates in polycarbonates (28) would be rewarding for other systems. 

Tewe, 0.0. 1982a. Protein supplementation of cassava diets for growing pigs effects on performance, nutrient utilization and cyanide metabolism. Nutr. Rep. Inter. 25 451-462. 

Gy, single exposure No effect on performance for at least 6 weeks 45... 

Wilson, M. S. Membrane catalyst layer for fuel cells. US Patent 5,234,777,1993. Xie, J., Garzon, R, Zawodzinski, T., and Smith, W. Porosimetry of MEAs made by "thin film decal" method and its effect on performance of PEFCs. Journal of the Electrochemical Society 2004 151 A1841-A1846. 

In actual use, many among the target population would necessarily receive multiples of the IDso and be unable to function within a few minutes. This would create both an early and dramatic psychological impact as well as a rapid effect on performance. BZ and similar belladonnoids would actually begin to cause casualties in a very short time. Unfortunately, because the official onset time is about four hours, the markedly more rapid onset of incapacitation at higher doses can easily be overlooked or ignored by military planners. 

Previously published civilian studies of drug effects on performance over time did not give this problem much consideration, and usually included only 1-3 practice trials. In some cases, improvement by the time of recovery was indeed evident, but for the investigators it was usually not a matter of great concern since the objectives of their studies were usually limited to showing a statistically significant rather than a precise degree of impairment. 

The IDso of 302196 produces essentially the same effect on performance, whether given by the intramuscular or the intravenous route (Fig. 51). Peak effects occur early, with a Tonso of abut 10 minutes. Partial recovery occurs at less than 4 hours and full recovery at about 10 hours. By both routes, the onset is very rapid and short dived. 

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