As a preliminary to the consideration of automated, or more correctly mechanized, methods for the determination of total organic nitrogen the discussion of some general aspects of nitrogen determination is illuminating. There are at least four recent reviews, for example those by Bradstreet (1965), Fleck & Munro (I965), Jacobs (1965), and Munro & Fleck (1969), of the determination of nitrogen f...

A procedure that is simple and convenient for general use for the estimation of calcium, magnesium, and phosphorus in diet and stool is described. It includes a HNO3-HCIO4 digestion in a micro-Kjeldahl flask. Calcium subsequently may be estimated by atomic absorption spectrophotometry or by the Clark-Collip procedure, magnesium by atomic absorption spectrophotometry, and phosphorus by the metho...

Nitrogen-to-protein conversion factors were calculated for diets and fecal samples from three animal species fed low- or high-fiber diets. The conversion factors based on protein contents determined by amino acid analyses were calculated from total N (Kjeldahl analyses) and recovered amino acid plus NH3-N (amino acid analyses). Conversion factors based on protein contents determined by a fluore...

Determination of total nitrogen in aqueous samples after potassium persulfate digestion compared favorably in both precision and nitrogen recovery with determinations obtained using Kjeldahl digestion. The determination of total nitrogen (TN = inorganic and organic fixed nitrogen) has largely depended either on acid Kjeldahl digestion ( cf. Strickland and Parsons 1972) or on photo-oxidation (Ar...

Within a military land activity context, relationships between stream water chemistry and watershed land use, topography and vegetation were explored at the Fort Benning Military Installation, Georgia. Water quality parameters, including pH, temperature, conductivity, total Kjeldahl nitrogen, total phosphorus, total organic carbon, chloride, and total suspended solids, were routinely measured i...

R. G. Canti [1916] bas used the hypobromite method for obtaining approximate values for the amount of urea in the cerebro-spinal fluid of patients suffering from a variety of diseases. Being desirous of controlling this method by others more reliable he asked R. L. M. Wallis to determine the urea by the urease method in some cases, and G. Graham by the Folin method in others, and the writer to ...

Manure management is an integral concern of Florida dairymen. Wastewater from nine dairy sprayfields on seven north Florida dairies with overhead sprinkler or gun irrigation facilities was collected biweekly from early September 1992 to Janu­ ary 1993. Samples were taken from the pump area of either anaerobic lagoons or settling ponds, rainfall, and from effluent plus rainfall in sprayfields. A...