What is Kawakita equation?

What is Kawakita equation?

The Kawakita equation. This equation has been promoted, especially by Japanese workers, since about 1960. Work is summarised in the paper by Kawakita and Ludde [8]. The equation is:(1) P a C = 1 ab + P a a where C is the relative volume decrease, i.e.:(2) C= V 0 −V V 0 and a and b are constants.

What does the Heckel equation measure?

The Heckel equation is one of the most useful equations for describing the compaction properties of pharmaceutical powders. Important material properties (e.g., yield strength) of powders can be derived using Heckel analysis. Two types of Heckel analysis are in common use.

What is Heckel plot?

The Heckel plot shows that the curve begins to adopt a tendency corresponding to the elastic deformation of the solid compact and therefore further compression does not affect the plastic deformation of the particles and also does not affect the formation of new bonds between the particles.

What is Heckel equation in physical pharmacy?

Heckel Equation: The Heckel equation is one of the most useful equations for describing the compaction properties of pharmaceutical powders. Heckel measured that decline in the voids follows the first order kinetics connection with applied pressure.

What order kinetics follow the Heckel equation?

Heckel equation is based on the postulation that the densification process of powder sample under force follows first-order kinetics.

What is pre compression force?

Pre-compression force mainly required for removing the entrapped air during compression. The hardness of the compressed tablet prominently governed by main compression force.

What is the difference between plastic strain and elastic strain?

When energy goes into changing the shape of some material and it stays changed, that is said to be plastic deformation. When the material goes back to its original form, that’s elastic deformation.

Which of the following is not true for zero order reaction?

Hence, on increasing concentration of reactants, rate of reaction does not increase. From Rate Law for Zero Order reaction, we can conclude that rate of reaction is independent of concentration of reactants. Hence, Option “A”, \ “B” \ \& \ “C” are not true.

What is the difference between D tooling and B tooling?

B Tooling: the same as BB tooling, only difference is the lower punch length is just 3 and 9/16th inch. D Tooling: its punches and dies usually have thicker diameter or greater diameter of their body as well as the tip of punches with greater outer diameter compared to B tooling.

What is AWC in compression machine?

Today AWC (auto weight control) machine is used for a better result. 4. Ejection: The ejection procedure for the tablet compression process involves removal of the tablet from the lower punch-die station. In this stage, the upper punch retracts from the die cavity and rises above the turret table.

How do you calculate elastic and plastic strain?

The plastic strain is obtained by subtracting the elastic strain, defined as the value of true stress divided by the Young’s modulus, from the value of total strain (see Figure 1).

What is Hooke’s law of elasticity?

Hooke’s law, law of elasticity discovered by the English scientist Robert Hooke in 1660, which states that, for relatively small deformations of an object, the displacement or size of the deformation is directly proportional to the deforming force or load.

What is pseudo unimolecular reaction?

In a chemical reaction if two or more reactants are involved but the rate of reaction depends only upon the concentration of any one of the reactant and independent of other reactants then it is said to be pseudo uni molecular reaction.