Determination of ΔH and ΔS Using the plot of lnKsp versus 1/T, the slope of the best-fit equation and the y-intercept was found. Using van’t Hoff equation, the change in enthalpy ΔH and entropy ΔS of the dissolution reaction was found to be 44 ± 1.3 kJ K-1 mol-1 and 89 ± 4 J K-1 mol-1 respectively. Using van’t Hoff equation, lnK = - (ΔH°reaction)/RT + (ΔS°reaction)/R where ΔH°reaction and ΔS°reaction ¬are the standard enthalpy and entropy change of the reaction respectively. From Figure 1, the gradient and y-intercept was obtained as shown in Table 4 in the Appendix. The enthalpy change and entropy change was then calculated.
Tilt of the octahedron structure is quantified by rotation angle as mentioned above and the value of β=0.322 is obtained via linear regression via approximation of the graph of ln ɸ vs ln (P-Pc). The rotation angle ɸ is a function of pressure, increasing smoothly with increasing pressure above the transition pressure 27.40KBar. M3 phonons degenerate on 3 different levels and there is a phase transition to P4/mbm, I4/mmm or Im3 structures from the original Pm3m structure via the condensation of either 1,2 or 3 M3 phonons respectively. Since these structures are all subgroups of the Pm3m structure, a phase transition from Pm3m to any of these structures can be regarded as of a 2nd order
Ductile metals like gold, copper and silver have a large plastic deformation range. Hard thermosetting plastics like rubber, crystals and ceramics have minimal plastic deformation ranges. Under tensile stress, plastic deformation is characterized by necking region and finally, fracture, which is also called rupture. Plastic deformation unlike on Elastic, includes the breaking of a limited number of atomic bonds by the movement of dislocations. However, the movement of dislocations allows atoms in crystal planes to slip past one another.
If permanent deformation occurs, incomplete recovery occurs leading to rapid loss of retention." According to Craig,44 "a material that is momentarily submitted to stress below its yield strength returns to its original form without any internal or structural change. However, if this stress is repetitive as in a fatigue process, the material can suffer definitive
For each setting the torque was calculated by multiplying the mass, gravitational acceleration and the radius together. Now it was possible to plot a graph Torque vs. angular acceleration where the slope represents the Inertia. In this case it turned out to be 0.0025 N. Introduction: The purpose of this paper was to find out the effect that different masses
And he considered nonlinear relationship between the lateral shear force and lateral deformation of R.C Framed G+5 story building is calculated first by the static analysis and then go through the pushover analysis by using ETABS software. The pushover analysis was including 8 steps it has been observed that one sub sequent push to building, hinges started forming in beams first. Initially hinges were in A-B stage and subsequently proceeding to B-IO stage. Out of 198 hinges 194 in A-B stage, 4 in B-IO stage. Overall performance of building is said to be B-IO
Unreacted shrinking core model The unreacted shrinking core model is applied when the reactant is converted to another solid material leaving behind a product layer around the unreacted particle core. Figure 5.3: Schematic diagram of shrinking core model The mathematical description of the shrinking core model under product diffusion control is based on the following assumptions The particle is considered to maintain its shape and size during the entire leaching process The low reaction and product concentrations in solution means the net flux due to diffusion is considered negligible The surface reaction is assumed to be first order and irreversible with respect to the reacting reagent. The reaction reagent is in excess and its concentration may be considered constant during the entire leaching process. The system may be considered to be in quasi steady state. Considering J to be the flux of B in Reaction 5.2 through a product layer in time t, then from Fick’s law: "J = -4π" "l" ^"2" "D" _"s" "dC" /"dl"
This requires a knowledge of the external forces and thermal transients experienced by the structure during service operation and representation of the cyclic and creep deformation properties of the materials of construction in terms of model constitutive equations irrespective of whether the local stress-strain is determined by approximate analytical solutions or finite element analysis, the constitutive model options are generally the same