The earliest known work on the attached plane jet was carried out by Forthmann (1934), which was described and quoted by Sigalla (1958), Schwarz and Cosart (1961), Reddy Gorla and Jeng (1971), Bajura and Catalano (1975), Rajaratnam (1976), Awbi (1991), and Imao et al.
The Test Sample. Ammonia is a waste product formed primarily by bacteria in the intestines during the digestion of protein. If not processed and cleared from the body appropriately, excess ammonia can accumulate in the blood. This test measures the amount of ammonia in the blood. Ammonia is normally transported in the blood to the liver, where it is converted into two substances called urea and glutamine. The urea is then carried to the kidneys, where it is eliminated in the urine.
Tests to check kidney function. When kidney function is decreased, substances such as urea, creatinine, and certain electrolytes begin to build up in the blood. The following tests measure levels of these substances to show how well your kidneys are working. The doctor can use the GFR to regularly check how well the kidneys are working and to stage your kidney disease. 2  A blood urea nitrogen (BUN) test measures how much nitrogen from the waste product urea is in your blood. 3  BUN level rises when the kidneys aren't working well enough to remove urea from the blood.