Effects of ammonium fluoride on the decomposition of geochemical samples as fluorinating agent and its analytical application.
In this work, the effects of ammonium fluoride on the decomposition of geochemical samples were investigated by analyzing some certified reference materials (CRM). The major and minor elements were detected by inductively coupled plasma optical emission spectrometry (ICP-OES), while trace and ultra-trace elements were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Decomposition time, temperature and the amount of ammonium fluoride were studied in detail. In the process of sample decomposition, on one hand, ammonium fluoride was used as the fluorinating agent because ammonium fluoride can be dissociated under acid medium to yield fluoride ions to attack silicon compound effectively. On the other hand, ammonium fluoride was used as a latent solvent since ammonium salt may dissolve insoluble fluorine compounds. The removal of insoluble fluorine compounds decreased the memory effect on digestion vessels caused by fluoride coprecipitation. By testing CRMs and many real samples, it was found that trace and ultra-trace elements could be digested using ammonium fluoride instead of hydrofluoric acid and the dissolution ratios of major and minor elements, for example Al, Ca, Mg, Fe, Na and K, improved noticeably. Moreover, the use of ammonium fluoride instead of hydrofluoric acid contributes to a greener environment and safer for operators.
Recommended Medical Treatment for Hydrofluoric Acid Exposure
This Booklet describes the special First Aid and Medical Treatment measures necessary following exposure to or injury from HYDROFLUORIC ACID. PREVENTION of exposure or injury must be the primary goal. Preventive measures include: 1. Making everyone who handles or uses HF aware of its properties and dangers. 2. Training everyone who uses HF in proper handling and safety precautions. 3. Utilizing all appropriate engineering controls, and making sure that the controls are maintained and functioning properly. 4. Requiring everyone who handles or uses HF to have available the proper safety and personal protective equipment, to be trained to use the equipment, and to always use the equipment when necessary. 5. Arranging ahead of time to provide first aid or medical treatment measures if necessary. NOTE: In addition to the usual medical history, the physician will find it helpful to obtain the following inform exposed/affected, first aid measures instituted (what, when, how long). Injuries due to dilute HF solutions or low
A study of the local tissue reactions in man to cortisone and compound F. VI. Histopathological studies of the local effect of compound F in normal and pathologic skin of man.
After our previous negative studies (1) of the local effect of cortisone acetate in the skin of man, a year ago, a parallel study of 17-hydroxycorticosterone-21-acetate, Compound F, was outlined. Theoretically, Compound F should be the active steroid. It was so suggested by Rothman (2), that in all probability Compound F and not cortisone would be active locally in the skin of man.