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Thermogravimetric analysis or thermal gravimetric analysis (TGA) is a method of thermal analysis in which the mass of a sample is measured over time as the temperature changes. . This measurement provides information about physical phenomena, such as phase transitions, absorption, adsorption and desorption; as well as chemical phenomena including chemisorptions, thermal decomposition, and ...
In thermodynamics, a temperature–entropy (T–s) diagram is a thermodynamic diagram used to visualize changes to temperature (T ) and specific entropy (s) during a thermodynamic process or cycle as the graph of a curve. It is a useful and common tool, particularly because it helps to visualize the heat transfer during a process.
Life cycle energy analysis (LCEA) is an approach in which all energy inputs to a product are accounted for, not only direct energy inputs during manufacture, but also all energy inputs needed to produce components, materials and services needed for the manufacturing process. [111] With LCEA, the total life cycle energy input is established. [112]
The reaction is used to make quick lime, which is an industrially important product. Another example of thermal decomposition is 2Pb(NO 3 ) 2 → 2PbO + O 2 + 4NO 2 . Some oxides , especially of weakly electropositive metals decompose when heated to high enough temperature.
Important thermal transitions include the glass transition temperature (T g), crystallization temperature (T c), and melting temperature (T m). The observed thermal transitions can be utilized to compare materials, although the transitions alone do not uniquely identify composition.
Temperature sensitive products such as foods, [4] pharmaceuticals, [5] and some chemicals are often monitored during shipment and logistics operations. Exposure to temperatures outside of an acceptable range, for a critical time period, can degrade the product or shorten shelf life.
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.
According to energy conservation and energy being a state function that does not change over a full cycle, the work from a heat engine over a full cycle is equal to the net heat, i.e. the sum of the heat put into the system at high temperature, q H > 0, and the waste heat given off at the low temperature, q C < 0.