Laboratory glass types

The high-pressure water supply is employed for the operation of the ordinary filter pump , which finds so many applications in the laboratory. Several types of water-jet pumps of glass, plastic or metal construction are available from most laboratory suppliers. These are often fitted with a suitable non-return valve to prevent the apparatus being flooded as a result of fluctuating water pressure. Connection to the water tap in the case of the metal pump is by a direct screw-threaded joint with the glass or plastic models high-pressure tubing of suitable bore is wired to the tap and to the pump. 

Many disposable glass laboratory items are made of soft glass. If a laboratory glass item does not specifically bear one of the words Pyrex , Kimax , or Duran in printed or raised letters, it is likely to be a soda-lime type of glass. 

In view of all these obvious or hidden drawbacks of methods I and II, a multicomponent saturator has been developed for the generation of gaseous feed streams in laboratory flow-type units [18, 19]. Its salient features (cf. Fig. 4) are a vertical saturator column packed with an inert solid, typically glass balls, and a moving liquid phase (as opposed to the saturators shown in Fig. 2) which trickles downwards, while the carrier gas A is conducted countcrcurrently. A pump conveys the liquid B + C-l----mixture from the storage vessel via a... 

The classic laboratory glass in Bohemia was the KS (Kavalier, Sazava) type which was manufactured since 1837 and employed till recently for less demanding purposes (a = 87 X 10 ). It did not contain B2O3, had a relatively high Si02 content (75 %) and a low alkali content (9.8% Na20 + 3.9% K2O by wt.). 

Waste Disposal In laboratories two types of wastes (i.e. liquid and solid) are often encountered. Arrangements have to be made for disposal of these wastes. For disposal of liquid wastes use of lead pipes or earthen ware pipes is considered most suitable. However care be taken to avoid the flow of solids like pieces of filter paper, cork, broken glass pieces etc. through these pipes, otherwise these pipes get chocked. For disposal of such solid wastes metal boxes or wooden boxes be provided. Such boxes be placed in the comers of the laboratory and students be asked to put all solid wastes in these boxes. Such waste boxes can even be placed under the sinks as shown in Fig. 

How does the behavior of each of these simple model systems, which are not obtainable as glasses in the laboratory, differ from that of the simplest type of laboratory glass-forming material, particularly in the description of transport behavior in the vicinity of the glass transition ... 

At the moment the noise in the mean squared displacement versus time curves does not permit easy observation of this type of time-dependent behavior, and it remains a matter for future investigation. Also of interest is the question of whether, under the highly diffusive conditions of computer simulations, the systems very near equilibrium relax exponentially ( single relaxation time ) or otherwise, as for laboratory glasses. ... 

Fig. 7. A bead filter, one of many types of biological filters, shown in association with a laboratory-scale recirculating water system. Small plastic beads inside the fiber glass chamber provide surface area for colonisation by bacteria that convert ammonia to nitrate.

Four column systems are available from Amersham Pharmacia Biotech that can be used to pack SEC media for various applications at the laboratory scale. These include C, XK, SR, and HR column systems. All of the laboratory-scale columns are constructed with borosilicate glass tubes. Columns for larger scale process applications include INdEX, BPG, EineLINE, BPSS, and Stack columns. The larger scale columns are constructed to meet stringent validation requirements for the production of biopharmaceuticals. Each of the column types are described. 

---