Polythene bags

Lithium aluminium hydride if carelessly manipulated may be dangerous for two distinct reasons. The material is caustic, and should not be allowed to touch the skin it is particularly important that the finely divided material should be kept away from the lips, nostrils and eyes, and consequently pulverisation in a mortar must be carried out with the mortar in a fume-cupboard, and with the window drawn down as far as possible in front of the operator. This danger from handling has however been greatly reduced, for the hydride is now sold in stated amounts as a coarse powder enclosed in a polythene bag in a metal container this powder dissolves readily in ether, and preliminary pulverisation is unnecessary. 

There are a number of applications for the acid, outlined in Scheme 6.5. The current major use is in the production of erucamide, a slip agent used in the manufacture of polythene bags to make them open more easily. 

Dry metal-impregnated charcoal catalyst was being added from a polythene bag to an aqueous solution under nitrogen. Static so generated ignited the charcoal dust and caused a flash fire. The risk was eliminated by adding a slurry of catalyst in water from a metal container. 

A violent explosion occurred when the lid was levered off an old paint tin used to contain a polythene bag of sodium chlorate. Subsequent tests showed that low energy input (0.2 J) would cause explosion of unconfined chlorate on a rusty steel surface. The presence of contaminants (sawdust, copper acetate, paint flakes or shredded polythene) increases the sensitivity, and a mixture with paint flakes and polythene caused 100 mg portions to explode under 0.2 J impact in 24 out of 100 attempts. 

Iron flake powder and polystyrene beads had been blended in a high-speed mixer. The mixture ignited and binned rapidly when discharged into a polythene bag. Rapid oxidation of the finely divided metal and/or static discharge may have initiated the fire. No ignition occurred when the iron powder was surface coated with stearic acid. 

Addition of sodium hydride to a damp reactor which had not been pinged with inert gas caused evolution of hydrogen and a violent explosion. Solid dispersions of the hydride in mineral oil are more easily and safely handled [1], When an unprotected polythene bag containing the hydride was moved, some of the powder leaked from a hole, contacted moisture and immediately ignited. Such materials should be kept in tightly closed containers in an isolated, dry location [2],... 

Biological material in a polythene bag filled with oxygen and being prepared for analytical combustion exploded. Diethyl ether used to anaesthetise the experimental animal from which the sample was derived may have still been present, and ignition from static charge on the plastics bag may have been involved. 

Galvanized sampling tools should not be used for trace element analysis. Usually from 20 to 25 cores are taken in a W pattern across the whole area. An alternative approach is to traverse the whole area in a zig-zag manner, sampling at random along different sections of the area (Scott et ai, 1971). The cores should be broken up and mixed well in a bucket, then about 200 g retained in a labelled polythene bag. 

Chemical. To check against the possibility of errors either in the sampling procedure or in the value taken for the total volume of gas passed through the arc, the total amount of acetylene produced was estimated by a wet chemical method. The total volume of gas collected in the Polythene bag was used for this analysis. Acetylene determination was made using potassium mercuric iodide, dissolved in potassium iodide, in the presence of sodium hydroxide. 

Place each blot strip in a suitably sized polythene bag, and add 1 mL of neat culture supernatant or purified antibody (10 pg/mL in PBS-Marvel) for every 20 cm2 of membrane... 

When moving the samples, place each Kraft bag in a 15 x 40 cm polythene bag and secure the top of the bag with a knot to prevent loss or cross contamination of samples during transport. 

Slot the polythene bags containing the tuber sample and SEB into the frame of a HOMEX 6 Plant Tissue Homogenizer, and grind. 

Potatoes are sampled on a disposable surface (such as a polythene bag) on top of a ceramic tile, giving a clean cutting surface for each tuber. 

Sampler 2 collects the pH and conductivity/alkalinity samples immediately after the filtered water samples. Like the filtered samples, they should be collected from the mid-stream flow, on the upstream side of the sampler. Thoroughly rinse the sample containers and caps with stream water three times. Submerge the containers in the stream to fill then seal underwater, ensuring that all air has been expelled. Place the unfiltered samples into a clean, self-seal polythene bag along with the knotted bag containing the filtered water samples. 

Sampler 2, in order to complete the water colour and suspended solids part of the field form, needs to determine these by filling a polythene bag (15 x 43 cm) with stream water and holding it up against the sky as a background to observe the water colour and opacity. 

After grading, the cardamom needs to be stored over a period of time and is normally kept in double-lined polythene bags. During storage, some storage pests do impair... 

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