Double calorimeter

The authors have reported the formation and thermodynamic parameters (K, A H, A S ) of fluoride complexes of the Mn(II) - Zn(II) series in three papers [76KUL/BLO], [81KUL/BLO], [83AVR/BLO]. In the first paper [76KUL/BLO] they reported the stability constants and thermodynamic functions of complex formation determined at 298.15 K and at 7 = 3 M NaC104, by means of a fluoride-selective electrode and a differential double calorimeter. The experiments were performed in the presence of an excess of metal ions (0.1 M Me(C104)2) to assure the formation of only monofluoro complexes. 

DOUBLE CALORIMETER FOR MEASURING THE HEAT CAPACITY OF ADSORPTION SYSTEMS. 

The calorimeters used for flic measurement of the heat of reaction can also be used for a measurement of the latent heat of vaporization. These are calorimeters for liquids, micro-calorimeters, mass calorimeters, and double calorimeters. ... 

Neutrinoless double-beta decay and other rare decays studied using massive calorimeters. 

Cryogenic detectors (calorimeters) were proposed in the 1980s by Fiorini and Niinikoski for searching rare events like neutrinoless double-beta decay ( 3 3-Ov) [52],... 

Elba reaction org chem The formation of anthracene derivatives by dehydration and cycllzation of diaryl ketone compounds which have a methyl group or methylene group heating to an elevated temperature is usually required. elbs re.ak shan ( ELDOR See electron electron double resonance. ( el,dor or e el de o ar ( electrical calorimeter analy chem Device to measure heat evolved (from fusion or vaporization, for example) measured quantities of heat are added electrically to the sample, and the temperature rise is noted. a lek tra kal kal a rlm ad ar)... 

Parr adiabatic calorimeter containing a Parr double-valve oxygen combustion bomb. The water equivalent of the calorimeter was determined from the combustion of a weighed sample of benzoic acid standardized by the National Bureau of Standards (NBS). The agreement between results of any two acceptable runs was better than 0.10%. 

Latent heats of evaporation of liquefied gases at low temperatures have been determined by various methods. Dewar, and Behn, dropped pieces of metal of known specific heat into the liquid and measured the gas evolved. Estreicher heated the liquid in a double Dewar vessel electrically and measured the volume of gas evolved. In Donath s apparatus (Fig. 4.VIII L) the gas passed through a copper spiral in a block of lead A, so assuming a constant temperature about 2° above the temperature in the metal calorimeter B. The gas then passed to a vessel inside B connected by a thin German-silver tube. The calorimeter was in two parts, between which was a platinum heating spiral for determining the thermal capacity. Outside was an adiabatic mantle C. The whole was in a vacuous copper jacket D. The temperature differences between A and B, and B and C, were determined by thermocouples. The rise in temperature... 

RC measurements can be classified either as devices using jacketed vessels with control of the jacket temperature (heat balance calorimeters, heat flow calorimeters and temperature oscillation calorimeters) or as devices using a constant surrounding temperature, e.g., jacketed vessels with a constant jacket temperature, (isoperibolic calorimeters and power compensation calorimeters) such instruments may also feature single or double cells. 

Fig. 12. Double isothermal wire calorimeter probe for low pressure flow system.

Sokollu [28] described a calorimeter made of a double-walled brass vessel, with internal stirrer and a conical metallic sound diffuser to scatter the beam in a random... 

The solution of the sample in a 2 1 mixture of concentrated hydrofluoric and nitric acids at Tref = 298 K was chosen as the reference state. The relative enthalpy, 7/rei(7m), was measured by indirect method of double calorimetry. This procedure enables us to determine Hiei(Tm) as the sum of enthalpy increase measured during the cooling of the system in a drop calorimeter (Acooi and during its dissolution in a solution calorimeter (Asoi//). Equation (4.34) can thus be written in the form... 

The //rei values determined by double calorimetry are independent of the magnitude of both Acooif and Asoi//. In silicate systems, they often vary when one composition is repeatedly measured. This may happen because the value of Acooi (and hence that of Asoif7 also) depends on the non-reproducible state of the sample after cooling down in the drop calorimeter. The samples may often consist of a mixture of glass and crystalline phases including not only the components of the system but also the products of their decomposition. 

Hydrogenation was carried out under mild conditions in an electrically calibrated calorimeter. Only the exocyclic double bond was hydrogenated. 

The copper calorimeter works on the principle of the mixture calorimeter in place of the calorimetric liquid there is a copper block with good thermal insulation, provided with an axial cavity for receiving the warmer or cooler substance under investigation. The change in the temperature of the block is measured with the aid of thermocouples the good thermal conductivity of copper ensures that all parts of it are always at practically the same temperature. With a view to the best thermal in-FlG 3- sulation, it is contained in a double-walled vessel which is evacuated and silvered. 

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