Chamber autoclave

Heat-distribution studies include two phases (1) heat distribution in an empty autoclave chamber and (2) heat distribution in a loaded autoclave chamber. Between 10 and 20 thermocouples should be used per cycle. Thermocouples should be secured inside the chamber according to a definite arrangement (e.g., see Fig. 7) Teflon tape can be used to secure thermocouples. The trips where... 

One gram-molecular weight of water (18 g, i.e., 18 ml in the liquid state) as steam at 121 °C and 2.05 abs bar occupies a volume of approximately 15L. This means that when steam condenses at 121°C, it shrinks in volume by almost 1000 times. Consequently, additional steam spontaneously reaches the material to be sterilized. The condensate that forms can be easily removed from the autoclave chamber by means of a condensate trap or by continuous bleeding. 

To perform its microbiological inactivation action, the steam must come into contact with the micro-organisms. This can occur directly or indirectly. It occurs directly when the steam makes contact, for example, with a surgical instrument located in the autoclave chamber. It occurs indirectly when the steam is generated, for example, inside a sealed ampoule that contains an aqueous solution by heat exchange with the steam in the chamber. However, it is evident that it is impossible to steam-sterilize the inside of a closed empty ampoule or its contents if they are, for example, an anhydrous oil-based solution. 

When a container in the conditions noted earlier is sterilized in a conventional autoclave that operates with pure saturated steam, during sterilization a considerable overpressure with respect to the pressure inside the autoclave chamber is generated in the container. This is clearly attributable to the fact that the air (or gas) that was present at filling has remained in the container, whereas the air was eliminated from the autoclave chamber at the beginning of the process. Fig. 4 schematically explains the phenomenon in ideal conditions, i.e., considering air a perfect gas. 

Small unit volumes of effluent (up to 50 litres) can be treated in a steam autoclave, provided that adequate measures are taken to transfer the material in a safe and contained manner to the autoclave chamber. A Class III cabinet line or contained suite in which the work is performed, and to which the autoclave chamber has direct access provides excellent containment security, but is not conducive to the processing of more than a few litres at a time. Transport of liquid in a leak-proof secondary container permits larger volumes to be handled, but consideration must be given to the logistical problems associated with the transport, especially if the autoclave is situated in a relatively remote location, or is inside another suite. If the autoclave has one door only, procedures must be adopted to ensure that contaminated and safe materials are not mixed. Double door autoclaves permit the uni-directional flow of waste out of the facility, and in the UK are recommended or mandatory for the higher categories of containment. " ... 

Since the autoclave chamber is a pressure vessel, what provisions can be made to control the release of agent from the pressure relief devices which may be required ... 

Chamber loading. The volume of waste in the autoclave chamber has a major effect on the time required for decontamination. Also, how the bags or other contents are placed in the chamber affects the penetration of the steam. In order for the autoclave to operate properly, the steam must be able to circulate freely to reach the bottom of the chamber. 

Some high performance laminates consisting of carbon fiber webs and epoxy resins are cured in autoclaves. An autoclave is a pressure chamber in which the pressure is appHed hydrostatically. 

Great care is needed in the design of autoclaves and sterilization cycles because of the requirement for the presence of moisture. The autoclave must be loaded to allow complete steam penetration to occur in all parts of the load before timing of the sterilization cycle commences. The time required for complete penetration, the so-called heat-up time, varies with different autoclave constmction and different types of loads and packaging materials. The time may not exceed specific limits in order to guarantee reproducibility and, for porous loads, saturated steam. The volume of each container has a considerable effect on the heatup time whenever fluids are sterilized. Thermocouples led into the chamber through a special connector are often employed to determine heatup times and peak temperatures. The pressure is refleved at the end of each sterilization cycle. Either vented containers must be used or... 

The gravity-displacement-type autoclave rehes on the relative nonmiscibility of steam and air to allow the steam that enters to rise to the top of the chamber and fill it. The air is pushed out through the steam-discharge line located at the bottom of the chamber. Gravity-displacement autoclaves are utilized for the sterilization of Hquids and for unwrapped nonhoUow medical instmments at 134°C. 

Analysis of soils is an important task in the environmental researches. Reliability of ICP-MS results of soil analysis mainly depends on chemical sampling. Recently microwave systems are widely used for preparation of different samples. Influence of microwave radiation on sample ensures a complete decomposition of sample, greatly increases the mineralization, and allows possible losses of volatile elements to be minimized. In the given study to intensify decomposition of soils we applied the microwave sample preparation system MULTIWAVE (Anton Paar, Austria and Perkin-Elmer, USA) equipped with rotor from 6 autoclaves with TEM reaction chambers of 50 ml volume. 

It is common to sterilise the media and Petri dishes separately. When the medium is cooled to about 55 °C, in front of a flame or in a laminar flow chamber, lift the lid of the dish enough to pour about 25 ml of the medium to the desired depth and lower the lid in place. It is best to gently move the Petri dish in way that spreads a thin layer of agar uniformly without any ah bubbles. Distribution of media in the Petri dishes should be done in front of a flame. Most plastic Petri dishes are made of polystyrene and are not autoclaveable. Plastic Petri dishes are easily deformed during sterilisation at high temperature. Some plastic dishes can be autoclaved, but they ate more expensive. Please follow the instructions given by the manufacturer or obtain information from catalogues. 

The hydrogenation of ehtyl pyurvate (EtPy) was carried out at 23 °C in a SS autoclave equipped with an injection chamber for separate introduction of the modifier Cinchonidine (CD) and Troger s base (TB) was used as modifiers. Different batches of EtPy, (Fluka) and Pt/Al203 catalysts (Engelhard E 4759, 5 %w Pt, Dpt = 25 %) were used. Experimental details incliding GC analysis can be found elsewhere [3,12]. The optical yield was calculated as e.e. = ([R]-[S])/([R]+[S]). The e.e. values were corrected for the amount of racemic product formed in minor amount in the reactor prior to the injection of CD. 

Autoclave steam sterilization is a well-established and widely used procedure. Normally, steam enters through the top of the chamber (Fig. 9). Being lighter than air, it remains at the top of the chamber but steadily and continuously drives the air out of the chamber through the bottom vent throughout the sterilization cycle. The velocity of steam entering the... 

A hot air chamber used for heating or drying raw rubber, for vulcanising rubber products by the dry heat method, or for carrying out accelerated ageing by the air oven method. On the continent of Europe, the term oven is sometimes used in the sense of autoclave. 

Figure 3.3 Side- and top-view of the in situ infrared autoclave. A IR window B Turbine rotor C Reagent addition D Thermocouple E Opening between upper and lower chamber F Electrical heaters C Kalrez O-rings (from Ref [6], reproduced by permission of Elsevier).

Autoclave. (ABC 009) serial no. (provide number) autoclave is utilized for sterilization of solution buffer vessels, filters, filter housings, closures, filling machine dosing system, and support equipment. The unit has a chamber size of (width x length x height) mm and (provide volume) liter capacity with dual interlocking doors. 

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