Nonlinear differential equation stability is a very important feature of applied mathematics, as it has a wide variety of applications in both practical and physical life problems. The major object of the manuscript is to discuss and apply several techniques using modify the Krasovskii's method and the modify variable gradient method which are used to check the stability for some kinds of linear or nonlinear differential equations. Lyapunov function is constructed using the variable gradient method and Krasovskii’s method to estimate the stability of nonlinear systems. If the function of Lyapunov is positive, it implies that the nonlinear system is asymptotically stable. For the nonlinear systems, stability is still difficult even though the Lyapunov methods are applied. There has to find a positive definite Lyapunov function, and its derivative function has to be negative definite. A new approach had been tested in several …
Mixing aluminum nitrate nonahydrate with urea produced room temperatures clear colorless ionic liquid with lowest freezing temperature at (1: 1.2) mole ratio respectively. Freezing point phase diagram was determined and density, viscosity and conductivity were measured at room temperature. It showed physical properties similar to other ionic liquids. FT-IR,UV-Vis, 1H NMR and 13C NMR were used to study the interaction between its species where - CO ??? Al- bond was suggested and basic ion [Al(NO3)4]? and acidic ions [Al(NO3)2. xU]+ were proposed. Water molecule believed to interact with both ions. Redox potential was determined to be about 2 Volt from – 0.6 to + 1.4 Volt with thermal stability up to 326 ?.
KE Sharquie, AA Noaimi, E Abdulqader, WK Al-Janabi, J Dermatol Venereol, 2020 - Cited by 6
In this research, new compounds were synthesized via the reaction of dichloroacetic acid with two moles of piperidine. The novel acid 1 was converted to its ester 2. Acid hydrizide 3 was prepared by the reaction of hydrazine hydrate with new ester 2, which was later used to prepare derivatives of Schiff bases 4-13. In the last step, Schiff bases and thioglycolic acid were reacted to give thiazolidine derivatives 14-23. All these compounds were diagnosed using melting points, FTIR, 1HNMR and mass spectroscopy. Scheme 1 shows all the synthesized compounds' reaction steps and structures. Keywords: Thiazolidine; Schiff bases; biological activity; piperidine; dichloroacetic acid.
In this work, the nuclear electromagnetic moments for the ground and low-lying excited states for sd shell nuclei have been calculated, resulting in a revised database with 56 magnetic dipole moments and 41 electric quadrupole moments. The shell model calculations are performed for each sd isotope chain, considering the sensitivity of changing the sd two-body effective interactions USDA, USDE, CWH and HBMUSD in the calculation of the one-body transition density matrix elements. The calculations incorporate the single-particle wave functions of the Skyrme interaction to generate a one-body potential in Hartree–Fock theory to calculate the single-particle matrix elements. For most sd shell nuclei, the experimental data are well rep
... Show MoreThe problem of present study is determined by answering the following questions:
1) What is the effect of using the oral open- ended questions on Students' achievement in the third-stage of Arabic department in the college of Education? 2) What is the effect of the oral open-ended questions on developing the creative thinking of students in
... Show MoreBackground: Change in palatal vault shape and Reinforcement of high impact acrylic denture base resin may in turn affect the dimensional accuracy of acrylic resin and affecting the fitness of the denture.This study evaluated tostudy the effect of fiber reinforcement for high-impact acrylic resin denture base with different palatal vault shapes on adaptation or gap space between the denture base and the stone cast and compare with non-fiber reinforcement and effect of palatal vault shapes on adaptation of non-reinforced and fiber reinforced high impact denture base acrylic resin Material and method: Three different palatal vault shapes were prepared on standard casts using CNC (computer numerical control) machine. 60 samples of heat polymeri
... Show MoreBackground: Change in palatal vault shape and Reinforcement of high impact acrylic denture base resin may in turn affect the dimensional accuracy of acrylic resin and affecting the fitness of the denture. The aim of study is to evaluate the effect of fiber reinforcement for high-impact acrylic resin denture base with different palatal vault shapes on linear dimensional change and effect of palatal vault shapes on linear dimensional changes of non-reinforced and fiber reinforced high impact denture base acrylic resin Material and method: Three different palatal vault shapes were prepared on standard casts using CNC (computer numerical control) machine. 60 samples of heat polymerized high impact acrylic resin maxillary denture base were fabri
... Show MoreThe parametric programming considered as type of sensitivity analysis. In this research concerning to study the effect of the variations on linear programming model (objective function coefficients and right hand side) on the optimal solution. To determine the parameter (θ) value (-5≤ θ ≤5).Whereas the result، the objective function equal zero and the decision variables are non basic، when the parameter (θ = -5).The objective function value increases when the parameter (θ= 5) and the decision variables are basic، with the except of X24, X34.Whenever the parameter value increase, the objectiv
... Show MoreThis research aims to analyse the problem of organizations in general and universities in particular, in dealing with �quality subjects� in a world where these organizations face the risks of becoming side lined and possibly vanished without looking for solutions that allow them to move in an open arena where change becomes the key to those solutions. Change here must be strategic and planning must adopts a way for organizations to develop mechanisms to manage change itself. Management leaders play a central role in achieving the principle required to chart new trends for universities in dealing with quality as a strategy that allows excellence and competition in light of the success of the processes of change. Change through reengineer
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