Sampling calorimeter

Comparison of the calculated and measured CO concns suggests that considerable expansion takes place even in the highly confined calorimeter samples of these measurements... 

In flow calorimeters, samples of a culture grown in a bioreactor are continuously pumped through the measuring cell of a microcalorimeter. The sensitivity of the differential signal between the reaction vessel and the reference vessel is comparable to that obtained from microcalorimetry, e.g. [193]. From a practical point of view, they are quite flexible because they can be connected to any reactor but, due to transfer times in the minute(s) range, gas and substrate limitations must be considered. 

Two different foods are burned in a calorimeter. Sample 1 has a mass of 6.0 g and releases... 

Adiabatic calorimeters sample temperature is followed by surroundings temp ture. This is done in order to prevent any exchange of thermal energy betv sample and surroundings. 

Diathermal-conduction calorimeters-, sample temperature follows surround temperature by simple conduction. Either a heat flowmeter or a phase chc detection system is used. 

Isothermal crystallization of the oil or fat was monitored by a Perkin Elmer DSC 7 differential scanning calorimeter. Sample sizes range from 5 to 10 mg. The oil sample is heated to a temperature of 80°C at a heating rate of 5°C/min from ambient and held at that temperature for at least 10 min in order to totally erase all past crystallization memories. The sample was then cooled at a rate of 5°C/min until the desired crystallization temperature had been reached. The sample temperature was then maintained at this crystallization temperature for 2 h to monitor the complete crystallization behavior of the sample. Partial areas under the thermal curve were determined by means of the Perkin Elmer Pyris partial area analysis software. 

ChemLab Two different foods are burned in a calorimeter. Sample 1 has a mass of 6.0 g and releases 25 Calories of heat. Sample 2 has a mass of 2.1 g and releases 9.0 Calories of heat. Which food releases more heat per gram ... 

Setaram C80 heat flow calorimeter sample mass, polyisocyanate 264 mg, polyol 292 mg crucible, mixing cell with metallic membrane isothermal at 80 °C, sensitivity 1 jiV. Initially, the two reagents are isolated by a membrane and stabilized in the calorimeter at 80 °C. The membrane is cut, and mixing is effected by manual rotation of the stirrer. 

Setaram C80 calorimeter sample mass 3.895 g (use larger amounts of samples to ensure good homogeneity between resin and hardener) standard vessel (a glass tube is introduced into the vessel in order to make the cleaning of the vessel easier) heating rate 0.5 °C min. ... 

Figure 6.17 Idealized differential temperature-time functions measured with a differential scanning calorimeter. Sample with sudden exothermic transition (top) and sample with endothermic phase transition (bottom).

Adiabatic reaction calorimeter sample volume 7-11 ml. Phi-TEC II Different cells from 10 to 120 ml temperature range up to 500 °C pressure range up to 138 bat... 

Thermal analysis. Differential scanning calorimetry (DSC) was performed by means of either the TA 2920 DSC or the Perkin-Elmer DSC-7 calorimeter. Sample weights of 8 12 mg and a heating rate of 20 °C/min were used. The glass transition... 

For simplicity it is assumed that Cp is also the heat capacity of the empty reference calorimeter (sample holder). The equality of the heat capacities of the sample and reference holders is best adjusted experimentally otherwise a minor complication in the mathematics is necessary, requiring knowledge of the different masses and the heat capacity of aluminum or other calorimeter material. Checking the precision of several analyses with sample holders of different masses, it was found that matching sample and reference sample pans gives higher precision than calculating the effect of the different masses. ... 

The DSC measurements were run in a DSC 1 model Mettler Toledo differential scanning calorimeter. Samples of approximately 10 mg were accurately weighed in an analytical... 

Figure 18 Schematic illustration showing the general configurations of the two types of differential scanning calorimeter sample chamhers. (a) Constant heat flow into the sample chamber (b) modulated heat flow to maintain specific temperature ramp.

In semiadiabatic calorimeters, samples of concrete or mortars are insulated so that their hydration can be followed by measuring the temperature change of the sample. This is a relatively simple technique for following the hydration of large specimens (concrete), but it is also used to determine the heat of hydration of mortars, for example, in the standardised Langavant calorimeter according to EN 196-9 (2010). 

The nanogram-sized PBT sample on the chip sensor crystallizes at high temperatures about 2 orders of magnitude faster than does the milligram-sized DSC sample. The larger surface area-to-volume ratio for the smaller chip-based calorimeter sample results in significant deviations from bulk behavior. 

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