Search results
Results from the WOW.Com Content Network
This system is generally more accurate than heat balance calorimetry, as changes in the delta temperature (T out - T in) are magnified by keeping the fluid flow as low as possible. One of the main advantages of constant flux calorimetry is the ability to dynamically measure heat transfer coefficient (U). According to the heat balance equation:
Calorimetry requires that a reference material that changes temperature have known definite thermal constitutive properties. The classical rule, recognized by Clausius and Kelvin, is that the pressure exerted by the calorimetric material is fully and rapidly determined solely by its temperature and volume; this rule is for changes that do not involve phase change, such as melting of ice.
In solution chemistry and biochemistry, the Gibbs free energy decrease (∂G/∂ξ, in molar units, denoted cryptically by ΔG) is commonly used as a surrogate for (−T times) the global entropy produced by spontaneous chemical reactions in situations where no work is being done; or at least no "useful" work; i.e., other than perhaps ± P dV.
In more recent calorimeter designs, the whole bomb, pressurized with excess pure oxygen (typically at 30 standard atmospheres (3,000 kPa)) and containing a weighed mass of a sample (typically 1–1.5 g) and a small fixed amount of water (to saturate the internal atmosphere, thus ensuring that all water produced is liquid, and removing the need ...
In chemical thermodynamics, isothermal titration calorimetry (ITC) is a physical technique used to determine the thermodynamic parameters of interactions in solution. [ 1 ] [ 2 ] It is most often used to study the binding of small molecules (such as medicinal compounds) to larger macromolecules ( proteins , DNA etc.) in a label-free environment.
Protein folding problem: Is it possible to predict the secondary, tertiary and quaternary structure of a polypeptide sequence based solely on the sequence and environmental information? Inverse protein-folding problem: Is it possible to design a polypeptide sequence which will adopt a given structure under certain environmental conditions?
Differential scanning calorimetry (DSC) is a thermoanalytical technique in which the difference in the amount of heat required to increase the temperature of a sample and reference is measured as a function of temperature. [1] Both the sample and reference are maintained at nearly the same temperature throughout the experiment.
A representation of Hess's law (where H represents enthalpy) Hess's law of constant heat summation, also known simply as Hess's law, is a relationship in physical chemistry and thermodynamics [1] named after Germain Hess, a Swiss-born Russian chemist and physician who published it in 1840.