Preferred Language
Articles
/
ijs-3119
The Dynamics of Biological Models with Optimal Harvesting
...Show More Authors

      This paper aims to introduce a concept of an equilibrium point of a dynamical system which will call it almost global asymptotically stable. We also propose and analyze a prey-predator model with a suggested  function growth in prey species. Firstly the existence and local stability of all its equilibria are studied. After that the model is extended to an optimal control problem to obtain an optimal harvesting strategy. The discrete time version of Pontryagin's maximum principle is applied to solve the optimality problem. The characterization of the optimal harvesting variable and the adjoint variables are derived. Finally these theoretical results are demonstrated with numerical simulations.

Scopus Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu May 25 2023
Journal Name
Results In Chemistry
Synthesis and characterization of (E)-4-(((4-(5-mercapto-1, 3, 4-oxadiazol-2-yl) phenyl) amino) methyl)-2-methoxyphenol as a novel corrosion inhibitor for mild-steel in acidic medium
...Show More Authors

Metal corrosion is a destructive process for many industrial operations, including oil well acidizing and acid pickling. Therefore, numerous efforts made by many researchers to control the steel corrosion. In the present work, A (E)-4-(((4-(5-mercapto-1,3,4-oxadiazol-2-yl) phenyl) amino) methyl)-2-methoxyphenol (MOPM) has been synthesized and characterized as a new corrosion inhibitor for mild steel in 0.1 M hydrochloric acid. FTIR and 1 HNMR were used in the diagnosis of MOPM, while electrochemical polarization technique was employed to test the performance of inhibitor at various temperatures and inhibitor concentrations. Electrochemical studies showed that MOPM acts as a mixed-type inhibitor with a maximum inhibition efficiency of

... Show More
Publication Date
Fri Dec 08 2023
Journal Name
Iraqi Journal Of Science
Determination of Atenolol in pharmaceutical formulations by continuous flow injection analysis via turbidimetric (T180o) and scattered light effect at two opposite position (2N90o ) using Ayah 4SW-3D-T180 -2N90 -Solar - CFI
...Show More Authors

A simple, rapid and sensitive method for the analysis of Atenolol in pure and pharmaceutical preparation as an alternative analytical procedure were developed by continuous flow injection analysis via turbidimetric (T180o) and scattered light effect at two opposite position (2N90o). The method is based upon the formation of white precipitate for the ion pair compound by phosphomolybidic acid with Atenolol in aqueous medium. The precipitate is measured via the attenuation of incident light and scattering of the incident light in two opposite direction namely +90o and -90o angle were measured. Chemical and physical parameters were investigated. The linearity of Atenolol is ranged from (0.1-11) mmol.L-1, with correlation coefficient r=0.993

... Show More
View Publication Preview PDF
Publication Date
Tue Dec 13 2022
Journal Name
Dental Hypotheses
Comparative Evaluation of Marginal Microleakage Between Bulk-Fill, Preheated Bulk-Fill, and Bulk-Fill Flowable Composite Resins Above and Below Cemento-Enamel Junction Using Micro-Computed Tomography: An In Vitro Study
...Show More Authors

Objective: The aim of this study was to compare the marginal microleakage between bulk-fill, preheated bulk-fill, and bulk-fill flowable composite resins above and below cemento-enamel junction (CEJ) using micro-computed tomography. Methods: Sixty freshly extracted premolar teeth were prepared with a slot shaped cavities of a total of 120 Class II: 3mm (bucco-lingual), 2mm (mesio-distal) with mesial-gingival margin located 1mm coronal to CEJ, and distal gingival margin located 1mm apical to the CEJ. The samples were randomly divided into two main groups according to the restorative material (Tetric EvoCeram and 3M Filtek), and each group was further sub-divided into three subgroups according to the consistency (bulk fill, preheated bulk fil

... Show More
View Publication
Scopus (5)
Crossref (3)
Scopus Clarivate Crossref
Publication Date
Sun Apr 30 2017
Journal Name
Journal Of Engineering
Experimental Study on Heat Transfer and Friction Factor Characteristics of Single Layer Graphene Based DI-water Nanofluid in a Circular Tube under Laminar Flow and Different Heat Fluxes as Boundary Conditions
...Show More Authors

An experimental study was performed to estimate the forced convection heat transfer performance and the pressure drop of a single layer graphene (GNPs) based DI-water nanofluid in a circular tube under a laminar flow and a uniform heat flux boundary conditions. The viscosity and thermal conductivity of nanofluid at weight concentrations of (0.1 to 1 wt%) were measured. The effects of the velocity of flow, heat flux and nanoparticle weight concentrations on the  enhancement of the heat transfer are examined. The Nusselt number of the GNPs nanofluid was enhanced as the heat flux and the velocity of flow rate  increased, and the maximum Nusselt number  ratio (Nu nanofluid/ Nu base fluid)   and thermal performance factor

... Show More
View Publication Preview PDF
Publication Date
Sun Aug 13 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
In vivo study of compounds 3-(acetyl Salicyloyl)-5,6 –Oisopropylidene-L-ascorbic acid ,2,3- (acetyl Salicyloyl)-5,6 –O-isopropylidene-L-ascorbic acid and 2,3,5,6Tetra(acetyl Salicyloyl)-L-ascorbic acid
...Show More Authors

     In vivo study was made for the coumpounds 3-(ocetyl Salicyloyl)-5,6-O-isoprpy lideneL-ascorbicocid,2,3-(acetyl Salicyloyl )-5,6-o- isopropylidene-L-ascorbic acid and 2,3,5,6(acetyl Salicyloyl )-L- ascorbic acid .And a measurement was mod for the concentration of the liberated aspirin in blood samples a fter (2,3,4,6,8,10) hours of the initial dose for the animal .The results showed that the highest concentration of aspirin was after four hours of giving the dose to the animal which is in accordance with pharmacokinetics studies

View Publication Preview PDF
Publication Date
Thu Apr 28 2022
Journal Name
Iraqi Journal Of Science
A Load Balancing Scheme for a Server Cluster Using History Results
...Show More Authors

Load balancing in computer networks is one of the most subjects that has got researcher's attention in the last decade. Load balancing will lead to reduce processing time and memory usage that are the most two concerns of the network companies in now days, and they are the most two factors that determine if the approach is worthy applicable or not. There are two kinds of load balancing, distributing jobs among other servers before processing starts and stays at that server to the end of the process is called static load balancing, and moving jobs during processing is called dynamic load balancing. In this research, two algorithms are designed and implemented, the History Usage (HU) algorithm that statically balances the load of a Loaded

... Show More
View Publication Preview PDF
Publication Date
Wed Jul 01 2020
Journal Name
International Journal Of Pharmaceutical Research
Synthesis and identification of some new N-substituted quinazoline-4-one, thiazine-4-one and tetrazoline rings incorporating N-ethyl-2-(benzylthio)benzimidazole acetate and study their application as anti-oxidant agent
...Show More Authors

View Publication
Scopus (2)
Crossref (1)
Scopus Crossref
Publication Date
Sat Sep 23 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Synthesis and Characterization of New ligand ' ((2-{1..,[(2-hyd_roxy;..benzyli_dene)-hydrazono]- ethyl} benzen_e-l, 3, s--moll and ItComplexes W·itll. (Mn.(11 Fe(n), Cd<11J, a-nd Hg(n).) Tons
...Show More Authors

In :the   _pr  sent  _paper we report ths. ynthesis       ·of a new li:ga!!d..

[f4LJ      [{'2 {1-'[(2-hyd•:0xy-.ben:zy1i.den·e)..,bxcJrazanci}:etby-l }benzerie­

J,5 t;rtiol .aad its complexes Â·w-ith '('Mlif(1 J       Fev 1 ),  ed(J'l), and. :f.::I:g 01>-)

The ligand  \VS preP..ated rin tWo steps' • fp I t}Je nrst stea -soJutiQil Qf

-saUcyla[deeyeq.    ip       methatt:oJ .     re3ctcd    lU1der      reflux   

... Show More
View Publication Preview PDF
Publication Date
Mon Dec 25 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Extraction, Identification and Isolation of B-sitosterol from Iraqi Wild Awsaj plant (Lycium barbarum) Using UAE (Probe and Bath) and two isolation technique (HPTLC and PHPLC): B-sitosterol in Iraqi Awsaj plant
...Show More Authors

Awsaj (Lycium barbarum) is a plant belong to family Solanaceae serves as a good source of bioactive compounds like phytosterols which have many important biological activity. Literature survey available so far revealed that there was no studies about Iraqi wild Awsaj phytosterols especially B-sitosterol, there for the objective of this study was to examine the efficiency of ultrasound assisted extraction (probe and bath) as compared to the conventional (Soxhlet) extraction method for extraction of phytosterols especially B-sitosterol from fruits, leaves, stems and roots of Iraqi wild Awsaj plant. This goal was achieved by comparing the extraction mass yield, also by a quick and easy approach for identification and quantification of bioac

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Jun 03 2023
Journal Name
Iraqi Journal Of Science
Effect Effect Effect Effect Effect Effect Effect of Thickness on Some Physical PropertiesThickness on Some Physical PropertiesThickness on Some Physical PropertiesThickness on Some Physical PropertiesThickness on Some Physical Properties Thickness on Some
...Show More Authors

The effect of thickness variation on some physical properties of hematite α-Fe2O3 thin films was investigated. An Fe2O3 bulk in the form of pellet was prepared by cold pressing of Fe2O3 powder with subsequent sintering at 800 . Thin films with various thicknesses were obtained on glass substrates by pulsed laser deposition technique. The films properties were characterized by XRD, and FT-IR. The deposited iron oxide thin films showed a single hematite phase with polycrystalline rhombohedral crystal structure .The thickness of films were estimated by using spectrometer to be (185-232) nm. Using Debye Scherrerś formula, the average grain size for the samples was found to be (18-32) nm. Atomic force microscopy indicated that the films had

... Show More
View Publication Preview PDF