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Comparison Of Fe(II) And Fe(III)-Hydralazine Complexes, A Potentiometric And Spectrophotometric Studa
Get PDFIron in oxidation states (+2 and +3) is very essential element for human body, and its concentration significantly altered in cardio vascular disease. So the aim of the present work is to study the interaction of Fe(II) and Fe(III) with very commonly used antihypertensive drug hydralazine through potentiometric and spectrophotometric methods. The objectives of the work is to study the stoichiometry, behavior of the complexes in aqueous solution, effect of pH and behavior of this drugs towards both oxidation states of Iron. Both methods show that hydralazine forms a stable complex with both oxidation states of the metal, but the nature of complex changes with change in pH, ligand concentration and with time span. Both methods confirms 1:2 stoichiometry for Fe(II)-Hydralazine while 1:3 for Fe(III)-Hydralazine. Stabilities of both complexes were also calculated. For Fe(II)-Hydralazine complex values of log β1 and log β2 were found to be 4.99 and 7.58 respectively. For Fe(III)-Hydralazine complex log β1, log β2 and log β3 values were found to be 2.74, 7.39 and 11.32 respectively. At high ligand concentration hydralazine also show reducing properties. The study suggests a strong interaction of hydralazine with iron; however the nature of interaction is different with both oxidation states of iron
The Ongoing Study of the Chemistry of the Marine Inhabitants of The Ramsar Site of Port Royal, Jamaica
Get PDFResearch efforts to examine the chemistry of marine organisms collected from the Ramsar site of Port Royal, Jamaica, has led to the isolation of a range of compounds as diverse as the species from which they were derived. Six sponges, two algal species, one ascidian and one soft coral collected from the mangrove area and the shallow coastal reefs were studied to yield compounds including steroids, aromatic compounds and terpenoids
Regional Boundary Strategic Sensors Characterizations
Get PDFThis paper, deals with the linear infinite dimensional distributed parameter systems in a Hilbert space where the dynamics of system is governed by strongly continuous semi-groups. More precisely, for parabolic distributed systems the characterizations of regional boundary strategic sensors have been discussed and analyzed in different cases of regional boundary observability in infinite time interval. Furthermore, the results so obtained are applied in two-dimensional systems and sensors studied under which conditions guarantee regional boundary observability in a sub-region of the system domain boundary. Also, the authors show that, the existent of a sensor for the diffusion system is not strategic in the usual sense, but it may be regional boundary strategic of this system
Hermite collocation method for solving Hammerstein integral equations
Get PDFIn this paper, we are presenting Hermite collocation method to solve numer- ically the Fredholm-Volterra-Hammerstein integral equations. We have clearly presented a theory to …nd ordinary derivatives. This method is based on replace- ment of the unknown function by truncated series of well known Hermite expan-sion of functions. The proposed method converts the equation to matrix equation which corresponding to system of algebraic equations with Hermite coe¢ cients. Thus, by solving the matrix equation, Hermite coe¢ cients are obtained. Some numerical examples are included to demonstrate the validity and applicability of the proposed technique
On norms of composition operators on weighted hardy spaces
Get PDF The computation of composition operator on Hardy spaces is very hard. In this paper we propose a norm of a bounded composition operator on weighted Hardy spaces H2(b) induced by a disc automorphism by embedding the classical Hardy space . The estimate obtained is accurate in the sense that it provides the exact norm for particular instances of the sequence b. As an application of our results, an estimate for the norm of any bounded composition operator on H2(b) is obtained
Probabilistic Inventory Model Multi-Source Backlogged Probabilistic Inventory Model for Crisp and Fuzzy Environment
No full textThis paper proposed a multi-item multi-source probabilistic periodic review inventory model under a varying holding cost constraint with zero lead time when: (1) the stock level decreases at a uniform rate over the cycle. (2) some costs are varying. (3) the demand is a random variable that follows some continuous distributions as (two-parameter exponential, Kumerswamy, Gamma, Beta, Rayleigh, Erlang distributions).
The objective function under a constraint is imposed here in crisp and fuzzy environment. The objective is to find the optimal maximum inventory level for a given review time that minimize the expected annual total cost. Furthermore, a comparison between given distributions is made to find the optimal distribution that achieves the model under considerations. Finally, a numerical example is applied
On Solutions and Heteroclinic Orbits of Some Lotka-Volterra Systems: Solutions and Heteroclinic Orbits of Some LV Systems
No full textIn this work, a principle for getting heteroclinic orbit of a dynamical system has been proposed when the solution is known in a compact form. The proposed principle has been tested through its application to a three species Lotka-Volterra system, which may appear as a mathematical model of human pathogen system. The domain in parameter space involve in the model, and the region of initial condition for the existence of heteroclinic orbit have been derived
Global existence and uniqueness of the solution to a nonlinear parabolic equation
Get PDFConsider the equation
u’ (t) - u + | u |p u = 0, u(0) = u0(x), (1),
where u’ := du/dt , p = const > 0, x E R3, t > 0.
Assume that u0 is a smooth and decaying function,
||u0|| = sup |u(x, t)|.
x E R3 ,t E R+
It is proved that problem (1) has a unique global solution and this
solution satisfies the following estimate
||u(x, t)|| < c,
where c > 0 does not depend on x, t
Annual Reviewer Acknowledgement
No full textThe editorial team of the journal would like to thank the reviewers for their work in referring manuscripts during 2018
Comparison of Quantities of Information in the Human Memory
Get PDFA mathematical model of changing the amount of information in the abstract human memory is proposed in the presence of the subsequent "external discrete" training (filling the information). Under this model, the amount of information is a solution of impulsive differential equation with fixed moments of impulsive effects and variable structure. Sufficient conditions are proposed related to the moments and magnitudes of the impulsive effects (i.e., to the moments of discrete training and the volume of the received information), where the quantities of information in two different models of learning can be compared