Premature opening

Stress Relaxation. Copper alloys are used extensively in appHcations where they are subjected to moderately elevated temperatures while under load. An important example is the spring member for contacts in electrical and electronic coimectors. Critical to rehable performance is the maintenance of adequate contact force, or stabiUty, while in service. Excessive decrease in this force to below a minimum threshold value because of losses in spring property can lead to premature open-circuit failure (see Electrical connectors). 

High Process Check refrigerant temperature from 2. Premature opening of hot gas... 

In particular, vibrations and pulsations due to positive-displacement compressors can cause premature opening when the forces within the valve are anywhere near equilibrium and are acting as another upward force. For pilot-operated valves, some manufacturers provide pulsation dampeners in their pressure pick up lines so that the effect of these pressure spikes are compensated. As can be seen in Figure 6.21, for spring-operated SRVs, unfortunately, no provisions can be taken to compensate for this effect. 

Capsules manufactured for use on automatic filling machines, which covers almost all pharmaceutical capsules, have locking devices moulded into the side of the capsule (Figure 11.29). There are two locking positions, a pre-lock to prevent premature opening prior to the... 

FTO Failure to open. FTC Failure to close. R Rupture. FOD Failure on demand. PO Premature opening. 

Third, you would. suppose that parallel pumps are identical, that they were manufactured and assembled together. But it is possible that one pump of the pair is the dominant pump and the other is the runt pump. If you start the dominant pump first in the parallel system, and then decide to add the runt pump of the pair, the weaker pump may not be able to open the check valve. The pump operator perceives that the flow meter on the second pump is stuck or broken. This is because the second pump might be dead heading against a closed check valve, maintained that w ay by the dominant pump. If this situation exists, it may re.sult in premature failure of bearings and. seals, leading maintenance and operations personnel thinking that parallel pumps are problematic. 

In the low-pressure systems a shot of material is injected into the mould which, if it did not expand, would give a short shot. However, the expanding gas causes the polymer to fill the mould cavity. One important form of the low-pressure process is the Union Carbide process in which the polymer is fed to and melted in an extruder. It is blended with nitrogen which is fed directly into the extruder. The extruder then feeds the polymer melt into an accumulator which holds it under pressure (14-35 MPa) to prevent premature expansion until a predetermined shot builds up. When this has been obtained a valve opens and the accumulator plunger rams the melt into the mould. At this point the mould is only partially filled but the pressurised gas within the melt allows it to expand. 

Premature or delayed actuation (an actuation that occurs out of timing sequence) Won t stay open or closed... 

Spurious Operation c.l Opens Prematurely C.2 Failure to Rcclose once open d. Fails to Open on Demand... 

Thorough irrigation with normal saline is the first step in the care of an infected bite wound. The wound should be elevated and immobilized. Surgical closure may be advocated, especially for facial wounds. Wounds that are infected, at higher risk for infection, or older than 24 hours should be left open because premature closure can lead to disastrous infectious complications.43... 

The direct effects of ozone on plant species constituting the shrub layer in the conifer forest are not yet sufficiently understood to permit any conclusion to be drawn. In many sites where the conifer overstoiy is well developed, the shrub species are excluded completely. In more open pine stands, some shrubs are very common, such as skunk bush iAmorpha califomica) and white horn (Ceanothus cordulatus). Of these two species, only skunk bush shows highly visible chlorotic mottle of leaflets and premature defoliation where ozone dosages are high. A shrub species common to the lower chaparral zone, squaw bush Rhus trilobata), is even more susceptible to ozone injury. In the San Bernardino Moun-... 

Investigators are not out to assign blame. Actions taken to blame and shame generally do little to prevent similar incidents from occurring. Therefore, it is necessary to foster an open and trusting environment where people feel free to discuss the evolution of an incident without fear of reprisal. Without such a supportive environment, involved individuals may be reluctant to cooperate in a full disclosure of occurrences leading to an incident and the incident investigation may be concluded prematurely with the root causes left uncovered. 

Effects of antiarrhythmics. Antiarrhythmics of the Na -channel blocking type reduce the probability that Na+ channeb will open upon membrane depolarization ( membrane stabilization ). The potential consequences are (A, bottom) 1) a reduction in the velocity of depolarization and a decrease in the speed of impulse propagation aberrant impulse propagation is impeded. 2) Depolarization is entirely absent pathological impulse generation, e.g., in the marginal zone of an infarction, is suppressed. 3) The time required until a new depolarization can be elicited, i.e., the refractory period, is increased prolongation of the AP (see below) contributes to the increase in refractory period. Consequently, premature excitation with risk of fibrillation is prevented. 

The functional proteins in the cell have to be protected in order to prevent premature degradation. Some of the intracellularly active proteolytic enzymes are therefore enclosed in lysosomes (see p. 234). The proteinases that act there are also known as cathepsins. Another carefully regulated system for protein degradation is located in the cytoplasm. This consists of large protein complexes (mass 2 10 Da), the proteasomes. Proteasomes contain a barrel-shaped core consisting of 28 subunits that has a sedimentation coef cient (see p. 200) of 20 S. Proteolytic activity (shown here by the scissors) is localized in the interior of the 20-S core and is therefore protected. The openings in the barrel are sealed by 19-S particles with a complex structure that control access to the core. 

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