Mouthful

Once y/" has been determined, the impedance change in an eddy-current coil due to the crack can be calculated using the following integral over the crack mouth [3] ... 

This method relies on the simple principle that the flow of ions into an electrolyte-filled micropipette as it nears a surface is dependent on the distance between the sample and the mouth of the pipette [211] (figure B 1.19.40). The probe height can then be used to maintain a constant current flow (of ions) into the micropipette, and the technique fiinctions as a non-contact imaging method. Alternatively, the height can be held constant and the measured ion current used to generate the image. This latter approach has, for example, been used to probe ion flows tlirough chaimels in membranes. The lateral resolution obtainable by this method depends on the diameter of the micropipette. Values of 200 nm have been reported. 

Now transfer the cold distillate to a separating-funnel, and shake vigorously with about 50-60 ml. of ether run oflF the lower aqueous layer and then decantf the ethereal solution through the mouth of the funnel into a 200 ml. conical flask. Replace the aqueous layer in the funnel, and extract similarly twice more with ether, combining the ethereal extracts in the conical flask. Add 3-4 g. of dry powdered potassium carbonate to the ethereal solution, securely cork the flask and shake the contents gently. The ethereal solution of the phenol... 

Both chloramine-T and dichloramine-T have marked antiseptic properties, chloramine-T being most frequently used because of its solubility in water. Aqueous solutions of chloramine-T can be used either for external application, or for internal application to the mouth, throat, etc, as chloramine-T in moderate quantities is non-toxic its aqueous solution can also be effectively used when the skin has come in contact with many of the vesicant liquid poison-gases, as the latter are frequently organic sulphur or arsenic derivatives which combine with or are oxidised by chloramine-T and are thus rendered harmless. 

When three consistent readings are obtained, add a weighed pellet of the solute to T for this purpose it is important that the thermometer is not withdrawn, and the boiling is not interrupted. It is best to hold the pellet ready in a pair of forceps near the mouth of the side-arm of T, and then momentarily to remove the condenser, drop in the pellet and replace the condenser when the condenser is removed a small quantity of cold air entering the side-arm will cause slight condensation of the hot vapour, none of which will therefore escape. 

The combustion tube is empty, with the exception of the boat, up to the furnace mouth. The packing of the tube is considered in detail below. 

Warm about loo ml. of distilled water in a beaker to about 40 and with a portion of this thoroughly rinse out the mouth and reject the liquid. Again introduce about 20 ml. of the warm water into the mouth and mix with the saliva as completely as possible. Transfer the liquid so obtained into another beaker and then filter through a small fluted filter-paper into a small conical flask or boiling-tube. 

Hydrogen cyanide (inhaled) or alkali oanides (taken by mouth, rf. p. IQ2) inhale amyl nitrite from freshly opened capsules. Obtain medical attention urgently. 

If a liquid which is being heated in a beaker or a conical flask catches fire, it is frequently sufficient to turn off the gas (or other source of heating) below and then at once to stretch a clean duster tightly over the mouth of the vessel. The fire quickly dies out from lack of air, and the (probably valuable) solution is recovered unharmed. 

Flat-bottomed flask (the so-called Florence flask) with vial mouth. The sizes vary between 50 ml. and 40 litres. 

The following dimensions of the email flasks may be found useful. The internal seal must be inside the line of the long neck to enable the glass spiral to be inserted or removed easily. The mouth of the flask is preferably an un ground 510 or 514 socket. 

Oleum is marketed in all strengths up to ca. 70 per cent. SO3. From 0 to 40 per cent, free SO3, it is a liquid from 40 to 60 per cent, free SO3, it is a solid from 60 to 70 per cent, free SO3, it is liquid above 70 per cent, free SO3, it is a solid. The acid must be kept in ground glass stoppered, thick-walled bottles. If it is required to melt the acid, the stopper is removed, a watch glass placed on the mouth of the bottle, and the bottle placed in a layer of sand in an air bath which is warmed with a small flame. The bottle is fitted with a wash bottle attachment, and any desired quantity of acid is forced out by gentle air pressure from a hand or foot bellows (the mouth must not be used) this procedure is far more satisfactory than that of pouring the liquid acid from the bottle. 

Optional experiment. When all the air has been displaced, collect a test-tube of the gas over water (by appropriate inclination of the end of the delivery tube beneath the mouth of a test-tube filled with water and supported in a beaker of water). Observe the colour and odour of the gas. Ignite the test-tube of gas, and note the luminosity of the flame and the amount of carbon deposited. Pure acetylene is almost odourless the characteristic odour observed is due to traces of hydrides of phosphorus, arsenic and sulphur. 

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