Evacuation process

A pumping speed of 100 l/s alone is required to continuously pump away the quantity of gas flowing in through the leaks or evolving from the chamber walls. Here the evacuation process is similar to the examples given in Sections 2.3.1.1. However, in the case of a diffusion pump the pumping process does not begin at atmospheric pressure but at the... 

A round-bottomed flask is recommended in order to withstand the evacuation process. 

The use of bursting disc devices on the downstream side of safety valves may be considered in cases where corrosion or fouling of the valve trim may be a concern (a common problem in systems using common headers to evacuate process media). 

There are two mechanisms for contamination from McLeod gauges (1) contamination which is backstreamed into the system from the McLeod gauge and (2) contamination which comes from the McLeod gauge storage bulb during the evacuation process. 

Research by Carstens, Hord, and Martin displayed a relatively high level of mercury being pumped out of a McLeod gauge during the evacuation process. Typical readings (in mg/m3) were... 

Figure 10.12 FIs and C Is spectra from both alloy panels and Si wafer pieces attached to them. Top figure panels are from samples exposed to the evacuation process and bottom panels are from samples exposed to the O2 plasma cleaning process. The third trace in each of the bottom panels is from an alloy panel that was O2 plasma cleaned in a new reactor with minimal fluorine contamination, indicating that the high binding energy C Is peak is not associated with fluorocarbon bonding.

In order to find an effective route to pure stage-one salts, the interaction of graphite with AsFj + Fj was studied. The results in Table 1 show that a pure stage-one C AsF salt was produced by this route. Fig. 4 clearly indicates that the / distance decrease upon evacuation in these samples is very rapid compared with that of those made from graphite and AsFs alone. No AsFj was observed in the volatiles during the evacuation process, and this absence of AsFj in the galleries is probably the reason for the... 

The relative positions of the contaminated area, forward line of troops, and threat air defense systems will determine where helicopters may be used in the evacuation process. Some helicopters may be restricted to contaminated areas. Ground vehicles should be used to cross the line separating clean and contaminated areas. The routes used by ground vehicles to cross between contaminated and clean areas are considered dirty routes and should not be crossed by clean vehicles. Consider the effects of wind and time upon the contaminants some agents will remain for extended periods of time. 

Connect the apparatus to a water aspirator with a trap between the aspirator and the collection bottle. A distilled solvent is placed in the funnel and suction filtered directly into the solvent container. The air is removed during the evacuation process. The trap is used to prevent water contamination in the event the water pressure should decrease. 

In addition to knowing the natural course of the disease or injury, the triage officer also should be aware of the current medical assets, the current casualty population, the anticipated number and types of incoming casualties, the current status of the evacuation process, and the assets and casualty population at the evacuation site. Committing assets to the stabilization of a seriously injured casualty in anticipation of early evacuation and more definitive care would be pointless if evacuation could not be accomplished within the time needed... 

Triage is a matter of judgment by the triage officer. This judgment should be based on knowledge of medical assets, the casualty load, and, at least at unit-level MTFs, the evacuation process. Most importantly, the triage officer must have full knowledge of the natural course of an injury and its potential complications. 

This paper at first describes the behavioral mode characteristics of individuals in emergent evacuation process. By combining with Thurley model, analysis is conducted for its influence on evacuation effects in stages. Based on this, corresponding suggestions and measures are put forward. The suggestions provide valuable reference to enhance evacuation efficiency, lower evacuation risk in... 

Wan Qing, Li Huiguo. 1995. Dynamic Simulation of Victim Evacuation Process in Flood Storage Area (I)—Technology and Method Study. Journal of Geographical Sciences, Supplement 62-68. 

A typical example of the getter s ability to act as a chemical Hn situ pump to sorb residual gases after the evacuation process is shown in Figure 4.18, which compares the pressure trend in panels with and without the getter immediately after the evacuation and seal-off. 

Several studies have focused on methods to improve the planning and operational aspects of the evacuation process to maximize the utility of the existing transportation network (Han et al. 2006). Stepanov and Smith (2009) also review a series of evacuation models and suggest that modeling techniques can be grouped by computational techniques into analytical and simulation techniques. One class uses analytical optimization methods to offer routing policies, and then these are... 

Other co-solvent systems which do not freeze completely in commercial freeze-dryers were more diflicult to use, do not sublime but rather boil during the evacuation process, often resulted in unacceptable freeze-dried cakes, and may bypass condensers and contaminate vacuum pumps. Their use appears limited. Many of these types of solvents were near impossible to dry when levels used exceed 10%. 

Moisture is removed from the canister using a vacuum drying system or forced helium dehydration system. For canisters without high bum-up fuel, the vacuum drying system may be connected to the canister and used to remove all liquid water from the canister in a stepped evacuation process. A stepped evacuation process is used to preclude the formation of ice in the canister and vacuum drying system lines. The internal pressure is reduced to below 3 torr and held for 30 min to ensure that all liquid water is removed. 

Figure 3 shows the fraction of N2 removed from the column (ratio of the amount of N2 removed to the total amount of N2 initially present in the column as adsorbed and void gases) as a function of column pressure (P) during the evacuation process. It is much easier to remove the N2 from the column by evacuation when it is held less tightly (e.g. NaX). A much deeper vacuum is necessary to remove a substantial quantity of N2 from the zeolites when its selectivity of adsorption over O2 is large (e.g. CaX, CaLSX). 

Figure 4 shows the mole fraction of N2 in the column effluent gas during the above described evacuation process as a function of fraction desorbed (between pressure levels of 1.0-0.10 atmospheres). It also gives the specific quantities of the total desorbed gases from the zeolites and their average N2 compositions. 

Figure 4. N2 mole fraction of column effluent gas as function of total fractional amount desorbed for evacuation process of Figure 3.

Ice" crystals (of water or other liquid) so formed can remain in the work chamber as an impediment to good cleaning. They can also stay in the flow circuit throughout the evacuation process and be a threat to the proper functioning of the pumping system. 

The evacuation process for a vacuum chamber, like that of a distillation column, is effected with a rough vacuum pump, regardless of type, as follows ... 

Murakami, H., Takimito, K., Pomonis, A. 2012. Tsunami Evacuation Process and Human Loss Distribution in the 2011 Great East Japan Earthquake— A Case Study of Natori City, Miyagi Prefecture. 15 WCEE, Lisbon, Portugal, 10 pp. 

Direct all efforts in the area, including taking charge of the evacuation process and minimising property damage and loss... 

The Enchova Central Platform was located in the Campos Basin close to Rio de Janeiro, Brazil, and it was operated by the Brazilian company called Petrobras. On August 16,1984, the accident occurred due to a blowout, which, in turn, caused fire and explosion at the central platform. Although most of the workers were evacuated safely from the platform by helicopter and lifeboats, 42 of them lost their lives during the evacuation process [3,10]. 

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