Calorimeter manufacturers

CALORIMETRIC MEASOREMEMTS Solution calorimetry was performed at 298.2 0.1 K by using a C-80 differential flux calorimeter manufactured by Setaram. The energy equivalent of the calorimetric signal was determined by electric calibration. The reliability of the equipment was checked by the dissolution of tris-(hydroxymethyl) aminomethane (THAM). Agreement within 0.4% with the published value of +17.75 kJ. mol-1 ( 21) was obtained. 

Instead of the ignition circuit shown in the control box of Fig. 3, a low-voltage transformer can be used. Transformer ignition circuits are available commercially as accessories from calorimeter manufacturers or can be easily constracted. A suitable design is shown in Fig. 4. 

It should be noted that, in principle, all the flow calorimeters discussed here are capable of operating both in the gas/vapour phase and in the solution phase. However, the calorimeters manufactured by Setaram and Thermometric are generally used for solution-phase studies, whereas the Microscal instruments are designed specifically to facilitate gas/vapour-phase studies. For the purposes of this discussion, gaseous-phase flow calorimetry will centre around a consideration of the Microscal instruments, and solution-phase calorimetry will centre around the Setaram and Thermometric instruments. 

Because of the objective to observe vapor cloud fires during some of the releases, sensors were installed to measure flame velocity during these vapor cloud fires. Four calorimeters manufactured by Hy-Cal Engineering were installed at four downwind stations at a height of 1 m. Twenty-seven LLNL-developed flame-velocity sensors were deployed at nine towers downwind of the spill point at three different levels. 

Of course, the calorimeter manufacturers should not be blamed for the existing confusion of terms concerning calorimetric procedures. Yet one is left with the impression that commercial interests are incompatible with a frank disclosure of the disadvantages of a given measuring principle for the solution of a specific problem in this field. 

Salicylic acid, C7H603, is one of the starting materials in the manufacture of aspirin. When 1.00 g of salicylic acid burns in a bomb calorimeter, the temperature rises from 23.11°C to 28.91°C. The temperature in the bomb calorimeter increases by 2.48°C when the calorimeter absorbs 9.37 kj. How much heat is given off when one mole of salicylic acid is burned ... 

A bomb calorimeter is calibrated for a constant mass of water. Since the mass of the other parts remain constant, there is no need for mass units in the heat capacity value. The manufacturer usually includes the heat capacity value(s) in the instructions for the calorimeter. 

Apparatus and Procedure. The thermochemical measurements were made using a Parr fluorine combustion bomb and a National Bureau of Standards (NBS) isothermal calorimeter (No. 63090) manufactured bv the Precision Scientific Co. The bomb cylinder and all internal parts or the bomb were Monel. A Monel ampoule was fitted into the top of the bomb to retain the OF2 sample. The ampoule apparatus reduced the internal volume of the bomb from 380 to 315 cc. The ampoule screws... 

Procedure. The successful operation of tliis experiment requires close attention to detail, as there are possible sources of trouble that might prevent the experiment from woridng properly. The basic procedure is very similar for both Parr and Emerson calorimeters. Necessary changes in procedure will be provided by the instructor if an Emerson calorimeter is to be used. Although considerable detail is given below, further details on the operation of the Parr apparatus (including the adiabatic jacket) are available in a manual pubhshed by the manufacturer. ... 

Problem A manufacturer claims that its new dietetic dessert has fewer than 10 Calories per serving. To test the claim, a chemist at the Department of Consumer Affairs places one serving in a bomb calorimeter and burns it in O2 (heat capacity of the calorimeter = 8.151 kJ/K). The temperature increases 4.937°C. Is the manufacturer s claim correct Plan When the dessert burns, the heat released is gained by the calorimeter ... 

A large variety of analysers such as ion chromatographs, mass spectrometers, digital titrators, calorimeters, specific ion analysers, gas and liquid chromatographs and octane number analysers are manufactured with built-in microprocessors. 

The results of this series of tests demonstrate that the gas chromatograph can provide accurate and reliable heating value measurement. From the field testing, Group 2, we can see that the the 104-day average between the calorimeter and the gas chromatograph varies between 1.7 and 2.2 Btu/scf This number is within the combined accuracy tolerance as specified by the manufacturer. 

Ever since its invention in 1921, the Cutler Hammer recording calorimeter has utilized a stripchart recorder to display its instantaneous BTU and to provide a continuous BTU record. In the early years, the BTU record was merely for information, to check manufactured gas and gas mixing processes, or to assure that BTU minimiims are met. In this day of MMBTU, the BTU is a major component in the cost of gas sales. Those people using Cutler Hammer Calorimeters use the BTU information in the following different ways ... 

Prior to conversion trom manufactured gas to natural gas, the standard practice of the American gas industry was to calibrate its calorimeters with nydrogen. As natural gas gradually replaced manufactured gas in the 1940 s and 1950 s, the gas industiy became concerned about the use of hydrogen as a calibration gas. Although hydrogen has a calorific value reasonably close to that of the manutactured gas, it only has one third the calorific value of natural gas. 

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