Benedict method

Oxidation of the aldehyde group of an aldose to form a carboxyUc acid or carboxyUc acid anion is often used analytically to determine the amount of reducing sugar. The Benedict and Fehling methods measure the amount of reducing sugar present in a fluid. In these reactions, the oxidant, Cu ", is reduced to Cu". Cu" precipitates as CU2O, which can be measured in a variety of ways. In the ToUens test, Ag" is reduced to Ag. ... 

The need for methods of accurately describing the thermodynamic behavior of natural and synthetic gas systems has been well established. Of the numerous equations of state available, three--the Soave-Redlich-Kwong (SRK) (19), the Peng-Robinson (PR) (18) and the Starling version of the Benedict-Webb-Rubin (BWRS) (13, 20)--have satisfied this need for many hydrocarbon systems. These equations can be readily extended to describe the behavior of synthetic gas systems. At least two of the equations (SRK and PR) have been further extended to describe the thermodynamic properties of water-light hydrocarbon systems. 

Use of formulae Until recently, practical methods were not available for measuring energy expenditure in patients in hospital. Consequently, formulae, based on weight, height, age and gender of the patient were, and still are, in use. The earliest formulae were published in 1919, by Harris Benedict, who studied 239 individuals aged 15-73. These were used for many years but the values were found to be too high. In 1985, a study on 7000 individuals provided new formulae known as Schofield standards (Schofield, 1985 Table 2.4). Whichever formula is used, it provides only approximate values, since metabolic rate varies markedly between individuals. 

The method used for measuring energy expenditure of patients is indirect calorimetry, aldiough it can be calculated from die Harris Benedict or Schofield equations (Ch ter 2). 

Drug/Lab test interactlons Su tor am 6es may produce false-positive urinary glucose tests when performed by Benedict s method. Sulfisoxazole may interfere with the Urobilistix test and may produce false-positive results with sulfosalicylic acid tests for urinary protein. 

Potassium azide was claimed to be first prepd in 1898 by Dennis Benedict (Ref lb) and in the same year by Curtius Rissom (Ref 2), both by methods involving evapn of a soln of KOH neutralized with a slight excess of hydrazoic acid, HN3. This same method of prepn was described in 1894 by Dennis (Ref la). Browne Houlehan (Ref 3) obtd KNS by reactg metallic K with NH4N3 in liq NHj. Other methods of prepn are described by Hoth Pyl (Ref 16), Moldenhauer MiSttig (Ref 17), Wattenburg(Ref 17a), Franklin (Ref 19), Audrieth et al (Refs 21,... 

T. Curtius and J. Rissom, and L. M. Dennis and C. H. Benedict made the rubidium azide, RbN3, by the methods indicated in connection with lithium azide. 

Industrial Method //MA-1001, Technicon Industrial Systems, 511 Benedict Ave, Tarrytown NY 10591... 

Benedict applied exergy costing to the design of an air separation plant in 1949 see (58). Gaggioli used the methods for the optimal selection of steam piping and its accompanying insulation (50, 59). Evans, Tribus, El-Sayed and co-workers (53, 54) have developed the fundamentals of the subject, under the title of Thermoeconomics, and present chapters in this volume. 

These methods make use of available experimental knowledge combined with correlation techniques that may or may not be partially based on molecular concepts. They range from methods that are completely empirical to ones in which there is significant input from statistical mechanics (see Fig. 2). As an example of an approach that is almost fully empirical, one can cite the many modifications of the Benedict-Webb-Rubin equation of... 

The use of electrical current to induce thrombosis in hamster and dog has been described in the early 1950s by Lutz et al. (1951) and Sawyer and Pate (1953a,b). In general, two different approaches exist. One method produces electrical damage by means of two externally applied hook-like electrodes (Hladovec 1973 Philp et al. 1978). The other method uses a needle electrode which is advanced through the walls of the blood vessels and positioned in their lumen the second electrode is placed into a subcutaneous site completing the circuit (Salazar 1961 Romson et al. 1980 Benedict etal. 1986). 

The vibrational frequencies are essentially typical values which were taken from the experimental work of Plyler and Benedict (6), Reichman and Overend (7), Morino and Nakamura (8), Jones, et al. (9), Plether (j ), and King, et al. (1 ). The value of Wj as given by Plyler and Benedict (6) appears too low and was not included. Costain (1 ) has calculated the bond distances and angles based on a Isotopic substitution method. From this latter data, the moments of inertia are calculated to... 

B) Reducing Action of Sugars. Use the same method as in the study of aldehydes and ketones. To 5 ml of Fehling s or Benedict s... 

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