Gentle processing methods

Depending on production conditions, oils of varying quality are available. As exposure to temperature has a very negative impact on lemon products, only oils obtained by gentle production methods are sensorially valuable. During the distillative production process, all natural stabilizers are removed and the oil, therefore, has to be stored at low temperatures without exposure to air. 

A serious problem with the Knudsen cell is that it may not give an accurate picture of a vapor s composition (M, M2, M3, etc.) emitting from an open surface of hot metal, which is not in thermal equilibrium. More research is certainly needed in this area. A second problem is that mass spectrometry requires that the metal particle be ionized before mass analysis. Just the process of ionization may cause fragmentation of M2, M3, etc. Further research using very gentle ionization methods (using energetically controlled photons instead of electrons) is needed in this area as well. 

Method 1. From ammonium chloroplatinate. Place 3 0 g. of ammonium chloroplatinate and 30 g. of A.R. sodium nitrate (1) in Pyrex beaker or porcelain casserole and heat gently at first until the rapid evolution of gas slackens, and then more strongly until a temperature of about 300° is reached. This operation occupies about 15 minutes, and there is no spattering. Maintain the fluid mass at 500-530° for 30 minutes, and allow the mixture to cool. Treat the sohd mass with 50 ml. of water. The brown precipitate of platinum oxide (PtOj.HjO) settles to the bottom. Wash it once or twice by decantation, filter througha hardened filter paper on a Gooch crucible, and wash on the filter until practically free from nitrates. Stop the washing process immediately the precipitate tends to become colloidal (2) traces of sodium nitrate do not affect the efficiency of the catalyst. Dry the oxide in a desiccator, and weigh out portions of the dried material as required. 

The FAB source operates near room temperature, and ions of the substance of interest are lifted out from the matrix by a momentum-transfer process that deposits little excess of vibrational and rotational energy in the resulting quasi-molecular ion. Thus, a further advantage of FAB/LSIMS over many other methods of ionization lies in its gentle or mild treatment of thermally labile substances such as peptides, proteins, nucleosides, sugars, and so on, which can be ionized without degrading their. structures. 

---