| 摘要 |
<p>Butane, propane and other hydrocarbons which are liquefied either through cooling or through pressure, burn with a flame which is either blue, or a very transparent and colourless blue, that is to say that all the carbon molecules are burnt. A gel of methoxides of colouring salts, made into a gel using, by way of non-limiting example, hydroxypropylated methylcellulose, burns with a flame the colour of the compositions of salt chosen. As long as the density of the gel is greater than that of the liquefied gas (and of course gaseous), it remains at the bottom of the container under pressure. When the gas gets to the bottom of the container, the colouring molecules of the gel partly join themselves with the gas, rise up to the pressure relief device, then burn in the burner: one therefore knows that there is practically no gas left, the blue flame becoming coloured in the chosen colour. <IMAGE></p> |
