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Articles 208081 - 208110 of 5207130

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Finite Element Convergence Analysis Of A Schwarz Alternating Method For Nonlinear Elliptic Pdes, Messaoud Boulbrachene Apr 2025

Finite Element Convergence Analysis Of A Schwarz Alternating Method For Nonlinear Elliptic Pdes, Messaoud Boulbrachene

Sultan Qaboos University Journal For Science

In this paper, we prove uniform convergence of the standard finite element method for a Schwarz alternating procedure for nonlinear elliptic partial differential equations in the context of linear subdomain problems and nonmatching grids. The method stands on the combination of the convergence of linear Schwarz sequences with standard finite element L-error estimate for linear problems.

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Zero-Hopf Bifurcation In The Generalized Stretch-Twist-Fold Flow, Niazy H. Hussein, Azad I. Amen Apr 2025

Zero-Hopf Bifurcation In The Generalized Stretch-Twist-Fold Flow, Niazy H. Hussein, Azad I. Amen

Sultan Qaboos University Journal For Science

A zero-Hopf equilibrium in a three-dimensional system is an isolated equilibrium point which has a zero eigenvalue and a simple pair of purely imaginary eigenvalues. In general, for such an equilibrium, there is no theory for finding when some periodic solutions are bifurcated by perturbing the parameters of the system. In this work, we describe the values of the parameters for which a zero-Hopf equilibrium occurs at the equilibrium points in the generalized stretch-twist-fold flow. Thus, only one condition for parameters of the generalized stretch-twist-fold flow introduced in a system (Eq. 1) is found for which the equilibrium point is …

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Eventually Pointed Principally Ordered Regular Semigroups, G.A. Pinto Apr 2025

Eventually Pointed Principally Ordered Regular Semigroups, G.A. Pinto

Sultan Qaboos University Journal For Science

An ordered regular semigroup, , is said to be principally ordered if for every there exists . A principally ordered regular semigroup is pointed if for every element, we have . Here we investigate those principally ordered regular semigroups that are eventually pointed in the sense that for all there exists a positive integer, , such that . Necessary and sufficient conditions for an eventually pointed principally ordered regular semigroup to be naturally ordered and to be completely simple are obtained. We describe the subalgebra of generated by a pair of comparable idempotents and such that .

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Connected Components Of The Hurwitz Space For The Symmetric Group Of Degree 7, Haval M. Mohammed Salih, University Of Raparian, College Of Basic Education, Department Of Mathematic, Ranya, Kurdistan Region Of Iraq Apr 2025

Connected Components Of The Hurwitz Space For The Symmetric Group Of Degree 7, Haval M. Mohammed Salih, University Of Raparian, College Of Basic Education, Department Of Mathematic, Ranya, Kurdistan Region Of Iraq

Sultan Qaboos University Journal For Science

The Hurwitz space is the space of genus covers of the Riemann sphere with branch points and the monodromy group . Let be the symmetric group . In this paper, we enumerate the connected components of . Our approach uses computational tools, relying on the computer algebra system GAP and the MAPCLASS package, to find the connected components of . This work gives us the complete classification of primitive genus zero symmetric group of degree seven.

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Preliminary Investigations Of Allelopathic Effects And Herbicide-Based Eradication Of Mesquite (Prosopis Juliflora), Salim Al-Abdali, Azan Al-Dhuhli, Hassan Al-Reasi Apr 2025

Preliminary Investigations Of Allelopathic Effects And Herbicide-Based Eradication Of Mesquite (Prosopis Juliflora), Salim Al-Abdali, Azan Al-Dhuhli, Hassan Al-Reasi

Sultan Qaboos University Journal For Science

Velvet mesquite, locally known as al-ghaf bahri (Prosopis juliflora), is a well-known invasive alien plant species in several regions around the world, including Oman, with various environmental effects. The allelopathic effect of P. juliflora leaves and seed pods on native ghaf (P. cineraria) and a crop species, mung bean (Vigna radiata) was demonstrated. Results indicated that P. juliflora extracts have inhibitory effects on seed germination and seedling growth of both species, particularly on P. cineraria when exposed to pod extracts. For eradication experiments, three herbicides (tribenuron methyl, clethodim and 2,4-D & MCPA) were investigated to determine their inhibitory properties on …

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Assessment Of Heavy Metal Contamination In Soil In And Around Sohar Industrial Port Area, Oman, Maha Al-Jabri, Daniel Moraetis, Reginald Victor Apr 2025

Assessment Of Heavy Metal Contamination In Soil In And Around Sohar Industrial Port Area, Oman, Maha Al-Jabri, Daniel Moraetis, Reginald Victor

Sultan Qaboos University Journal For Science

The increase in the number of heavy metal emitting sources in industrial areas is a serious issue in pollution science. Sohar Industrial Port (SIP) area is located in the northern part of Oman where different industrial activities like petrochemical production, metal processing, and waste disposal are prevalent. This study comprehensively identified the presence and quantities of heavy metals in the soils of Sohar Industrial Port area and traced their origin to geogenic or anthropogenic sources. Bulk geochemical and mineralogical analyses were carried out on all samples. Environmentally available and bioavailable heavy metals were extracted by diethylenetriaminepentaacetic acid (DTPA) and were …

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Radiometric Surveys For Detection Of Uranium In Dhofar Region, Sultanate Of Oman, Narasimman Sundararajan, Bernhard Pracejus, Salah Al-Khirbash, Talal Al-Hosni, Ala Ebrahimi Ebrahimi, Ali Al-Lazki, Musallam Al-Mushani Apr 2025

Radiometric Surveys For Detection Of Uranium In Dhofar Region, Sultanate Of Oman, Narasimman Sundararajan, Bernhard Pracejus, Salah Al-Khirbash, Talal Al-Hosni, Ala Ebrahimi Ebrahimi, Ali Al-Lazki, Musallam Al-Mushani

Sultan Qaboos University Journal For Science

The Proterozoic basement of the Dhofar region of the Sultanate of Oman might be considered as a potential source of Uranium mineralization like other Proterozoic basins of the world, which collectively contribute 30%-40% to the global production. Uranium exploration assumes great importance in this part of the world and therefore geochemical and geophysical exploration for Uranium was initiated. Initial, random sampling of the study area with Gamma ray spectrometry as well as in situ XRF (Xray Florescence) analysis indicated the presence of around 30-40 ppm of Uranium. Since Gamma ray spectrometry results in the calculation of the heat produced during …

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Effect Of Alarm Chemicals And Predator Kairomones On The Behaviour Of Two Species Of Mosquito Larvae, Derek Roberts, Nargis Al-Alawi, Mai Al-Gharibi Apr 2025

Effect Of Alarm Chemicals And Predator Kairomones On The Behaviour Of Two Species Of Mosquito Larvae, Derek Roberts, Nargis Al-Alawi, Mai Al-Gharibi

Sultan Qaboos University Journal For Science

Mosquito larvae have developed a variety of responses to reduce the risk of predation, but this requires them to be able to identify the different species of predators and respond accordingly. We investigated the behavioural response of two mosquito species to three chemical signals: kairomones from two predators, and also to alarm semiochemicals from killed mosquito larvae. Culex perexiguus mosquito larvae are primarily surface filter-feeders. In response to all three chemical signals, they significantly reduced feeding by the high-risk active bottom scraping of biofilms in favour of the less active (and so lower predator-detection risk) surface filter feeding. Active escape …

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Preparation And Characterization Of Acidic, Basic And Hydrophobic Dehydrated Carbons And Their Capability For Methylene Blue Adsorption, El-Said El-Shafey, Syeda N.F. Ali, Haider Al-Lawati, Saleh Al-Busafi Apr 2025

Preparation And Characterization Of Acidic, Basic And Hydrophobic Dehydrated Carbons And Their Capability For Methylene Blue Adsorption, El-Said El-Shafey, Syeda N.F. Ali, Haider Al-Lawati, Saleh Al-Busafi

Sultan Qaboos University Journal For Science

Dehydrated carbon (DC) was prepared from date palm leaflets via sulfuric acid treatment. DC was functionalized via amide coupling using ethylene diamine (EDA) and propylene diamine (PDA) to produce basic dehydrated carbons (BDCs): BDC-EDA and BDC-PDA, respectively, and using ethylamine (EA) and aniline (AN) to produce hydrophobic dehydrated carbons (HDCs): HDC-EA and HDC-AN, respectively. Surface areas were found low, between 6.7-16 m2/g with mesoporosity domination. FTIR shows that –COOH content on DC almost disappeared after surface functionalization. Faster adsorption of methylene blue with larger adsorption capacity was found on HDC-EA than other adsorbents because of stronger hydrophobic interaction forces.

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Petroleum Hydrocarbon Residues In Surficial Sediment Samples From Aden City Coasts, Yemen, Ibrahim Al-Akhaly, Nabil Al-Shwafi, Basem Al-Matari, Eman I.Siam Apr 2025

Petroleum Hydrocarbon Residues In Surficial Sediment Samples From Aden City Coasts, Yemen, Ibrahim Al-Akhaly, Nabil Al-Shwafi, Basem Al-Matari, Eman I.Siam

Sultan Qaboos University Journal For Science

The environmental quality along Aden coasts is affected by the anthropogenic pressure of Aden city. Field work has been carried out to investigate the occurrence of petroleum pollution along these coasts. To determine the status of aliphatic hydrocarbon (AH) (n-C10 to n-C34) and polycyclic aromatic hydrocarbon (PAH) pollution in surface sediments, twenty seven surface sediment samples were collected in July and December 2014 and March 2015 and analysed for AHs and PAHs by using gas chromatography–mass spectrometry (GC-MS) to determine their levels and sources. Concentrations of AHs ranged from 6.25 µg/g at station 5 (Goldmoor) to 41.05 µg/g at station …

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Two Groups 2^3.〖Psl〗_2 (7) And 2^3:〖Psl〗_2 (7) Of Order 1344, Mehmet Koca, Ramazan Koc, Nazife O.Koca Apr 2025

Two Groups 2^3.〖Psl〗_2 (7) And 2^3:〖Psl〗_2 (7) Of Order 1344, Mehmet Koca, Ramazan Koc, Nazife O.Koca

Sultan Qaboos University Journal For Science

No abstract provided.

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An Overview Survey Of Recent Routing Protocols For Underwater Wireless Sensor Networks, Al-Salti Faiza A., Al-Zeidi Nasser M., Day Khaled, Arafeh Bassel, Touzene Abderezak Apr 2025

An Overview Survey Of Recent Routing Protocols For Underwater Wireless Sensor Networks, Al-Salti Faiza A., Al-Zeidi Nasser M., Day Khaled, Arafeh Bassel, Touzene Abderezak

Sultan Qaboos University Journal For Science

With the recent advances in underwater sensor devices and technologies, underwater wireless sensor networks (UWSNs) enable a variety of applications such as underwater exploration and monitoring, disaster prevention, and military surveillance and reconnaissance. However, these kinds of networks faces a number of challenges induced by the nature of the underwater environment and its influence on the physical media. Therefore, new routing protocols are proposed specifically for such networks to mitigate these challenges. This paper surveys some of the recent routing protocols for UWSNs. Specifically, the idea of each protocol is presented as well as its advantages and disadvantages. Furthermore, the …

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Effect Of Management System On Serum Copper Level And Haematology Of Jabal Akhdar Breed Goats In Two Sites In Al Jabal Al Akhdar Region Of Oman, I.E.D. Osman Nur El Huda, Bobade Patrick A. Apr 2025

Effect Of Management System On Serum Copper Level And Haematology Of Jabal Akhdar Breed Goats In Two Sites In Al Jabal Al Akhdar Region Of Oman, I.E.D. Osman Nur El Huda, Bobade Patrick A.

Sultan Qaboos University Journal For Science

ABSTRACT: Blood samples were collected from randomly selected healthy Jabal Akhdar breed goats reared in two sites in the Jabal Akhdar region of Oman. Seven males and 65 female goats, age range 2 months to 4 years, raised in Shnoot Al-Dar village were kept under a semi-intensive system (SIS) and 2 males and 18 females, age range 4 months to 5 years, raised in Al-Ala'lana village and kept the under free range system (FRS) were studied. Serum Cu and haematological values were measured. There were no significant (p>0.05) effects of age, sex or serum copper levels on the haematology …

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Nutritional Value Of Vegetable Wastes As Livestock Feed, Osman Mahgoub, Isam T. Kadim, Yasmin Eltahir, Sadeq Al-Lawatia, Abdulrahim M. Al-Ismaili Apr 2025

Nutritional Value Of Vegetable Wastes As Livestock Feed, Osman Mahgoub, Isam T. Kadim, Yasmin Eltahir, Sadeq Al-Lawatia, Abdulrahim M. Al-Ismaili

Sultan Qaboos University Journal For Science

ABSTRACT: A study was carried out to evaluate the nutritional value of waste from lettuce, green cabbage, red cabbage and cauliflower to determine their potential use for feeding to livestock. Vegetable wastes were dried in a solar tunnel drier. The crude protein (CP), ether extract (EE), total ash, acid detergent fiber (ADF) and neutral detergent fiber (NDF) were 24.1, 2.7, 24.7, 29.3 and 29.0%; 17.7, 2.3, 13.7, 25.6, and 28.7%; 11.9, 1.9, 8.8, 23.1 and 25.6%; 10.3, 0.5, 7.0, 16.1 and 19.6 % (DM basis) in cauliflower, lettuce, green cabbage and red cabbage, respectively. The gross energy (MJ/kg DM) in …

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Preliminary Assessment Of Utilization Of Al-Jaif Scoria (Nw Sana’A, Yemen) For Cement Production, Al-Akhaly Ibrahim A., Al-Anweh Ahmed M., El-Anbaawy Mohammed I. Apr 2025

Preliminary Assessment Of Utilization Of Al-Jaif Scoria (Nw Sana’A, Yemen) For Cement Production, Al-Akhaly Ibrahim A., Al-Anweh Ahmed M., El-Anbaawy Mohammed I.

Sultan Qaboos University Journal For Science

This paper presents the results of investigations on the potential industrial utilization of scoria, collected from Al-Jaif quarry, NW Sana'a, Yemen as a cement additive. Scoria was chosen as a cement additive material due to its availability and low cost from the Sana’a-Amran volcanic field in Yemen. The chemical composition of scoria was determined by X-ray fluorescence (XRF). The studied scoria is mainly composed of volcanic glass with a few zeolites (e.g. clinoptilolite) as revealed from petrographic investigation and X-ray diffraction (XRD). The scoria was added to the clinker in the range of 2, 4, 6, 8, 10 and 12% …

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Synthesis Of A Flavone Based Fluorescent Probe Bearing A Nitroolefin Moiety For Selective Detection Of Cysteine, Al-Busafi Saleh N., Al-Hamami Nadia M., O. Suliman Fakhr Eldin, Varghese Beena Apr 2025

Synthesis Of A Flavone Based Fluorescent Probe Bearing A Nitroolefin Moiety For Selective Detection Of Cysteine, Al-Busafi Saleh N., Al-Hamami Nadia M., O. Suliman Fakhr Eldin, Varghese Beena

Sultan Qaboos University Journal For Science

In this paper, we report the synthesis, characterization and investigation of the optical properties of a new fluorescent probe, 4ʹ-nitroolefinylflavone (4ʹ-NOF) 1, based on a flavone skeleton and bearing a nitroolefin moiety. Upon the addition of cysteine, a remarkable fluorescence enhancement (200 fold) was observed for probe 1 accompanied with a slight blue shift from 457 nm to 459 nm. The prepared probe displays high selectivity and sensitivity towards cysteine over other amino acids. The Michael addition of cysteine to probe 1 was confirmed by 1H-NMR spectroscopy. The detection limit of probe 1 towards cysteine was found to be 1.63 …

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Slope Stability Assessment And Landslide Susceptibility Map Production Of Wadi Dhahr Area, Northwest Of Sana’A, Yemen, Barahim Adnan A., Khanbari Khaled M., Yemen Remote Sensing And Gis Center, Algodami Amal F., Almadhaji Ziad A., Adris Ahmed M. Apr 2025

Slope Stability Assessment And Landslide Susceptibility Map Production Of Wadi Dhahr Area, Northwest Of Sana’A, Yemen, Barahim Adnan A., Khanbari Khaled M., Yemen Remote Sensing And Gis Center, Algodami Amal F., Almadhaji Ziad A., Adris Ahmed M.

Sultan Qaboos University Journal For Science

A slope stability assessment of Wadi Dhahr area, located northwest of Sana’a the capital of Yemen, was carried out in this study. The study area consists of sandstone and volcanic rocks that are deformed by number of faults, joints and basaltic dykes. All the important factors affecting slope stability in the area such as slope angle, slope height, discontinuities measurements, weathering, vegetation cover, rainfall and previous landslides were evaluated. The study was conducted based on the integration of field investigation and satellite image processing. A landslide susceptibility map was produced with the Landslide Possibility Index (LP1) System, and the correlation …

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Initial And Boundary Value Problems For Fractional Differential Equations Involving Atangana-Baleanu Derivative, Al-Musalhi Fatma S., Al-Salti Nasser S., 2fracdiff Research Group, Sultan Qaboos University, Muscat, Sultanate Of Oman, Karimov Erkinjon, Institute Of Mathematics, Uzbekistan Academy Of Sciences, Tashkent 170, Uzbekistan Apr 2025

Initial And Boundary Value Problems For Fractional Differential Equations Involving Atangana-Baleanu Derivative, Al-Musalhi Fatma S., Al-Salti Nasser S., 2fracdiff Research Group, Sultan Qaboos University, Muscat, Sultanate Of Oman, Karimov Erkinjon, Institute Of Mathematics, Uzbekistan Academy Of Sciences, Tashkent 170, Uzbekistan

Sultan Qaboos University Journal For Science

In the present work, an initial value problem involving the Atangana-Baleanu derivative is considered. An explicit solution of the given problem in integral form is obtained by using the Laplace transform. The use of the given initial value problem is illustrated by considering a boundary value problem in which the solution is expressed in the form of a series expansion using an orthogonal basis obtained by separation of variables. Some examples are also given to illustrate the obtained results.

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A One-Dimensional Model Of Thermo-Electroelasticity In Extended Thermodynamics, Moustafa Saber Abou-Dina, Ahmed Ahmed F. Ghaleb Apr 2025

A One-Dimensional Model Of Thermo-Electroelasticity In Extended Thermodynamics, Moustafa Saber Abou-Dina, Ahmed Ahmed F. Ghaleb

Sultan Qaboos University Journal For Science

The subject of thermo-electroelasticity involves many complications due to the multiple ways in which the mechanical, thermal and electric fields can interact, some of these involving non-linearities. In extended thermodynamics, an additional difficulty arises due to the requirement of finiteness of the speed of propagation of the thermal disturbances. This implies, as may be observed in the extensive literature on the subject, a re-visiting of the basic postulates of thermodynamics, ultimately leading to the desired generalization. There are only a few nonlinear models dealing with this subject. In order to consider general nonlinear models, it is necessary to study linear …

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The Mathematical Modelling Of A Fixed Source Of Dust, Khaled S.M. Al-Mashrafi Apr 2025

The Mathematical Modelling Of A Fixed Source Of Dust, Khaled S.M. Al-Mashrafi

Sultan Qaboos University Journal For Science

A mathematical model for the diffusion of dust particles emitted from a fixed source is investigated using the atmospheric diffusion equation. This model poses an initial boundary value problem with a second order linear partial differential equation. The steady state case of this problem when the uniform source is situated at ground level was examined by Sharan et al. [1]. The solution of the unsteady case in closed form for a time dependent source is derived. Two special cases, in which the source function of time is explicitly given and special values of the diffusion parameters are taken, are examined …

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Numerical Simulations Of A Delay Model For Immune System-Tumor Interaction, Mohamed A. Hajji, Qasem Al-Mdallal Apr 2025

Numerical Simulations Of A Delay Model For Immune System-Tumor Interaction, Mohamed A. Hajji, Qasem Al-Mdallal

Sultan Qaboos University Journal For Science

In this paper we consider a system of delay differential equations as a model for the dynamics of tumor-immune system interaction. We carry out a stability analysis of the proposed model. In particular, we show that the system can have up to two steady states: the tumor free steady state, which always exist, and the tumor persistent steady state, which exists only when the relative rate of increase of the tumor cells exceeds the ratio between the natural proliferation rate and the relative death rate of the effector cells. We also determine an upper bound for the delay, such that …

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A New Second Order Approximation For Fractional Derivatives With Applications, Haniffa M.Nasir, Kamel Nafa Apr 2025

A New Second Order Approximation For Fractional Derivatives With Applications, Haniffa M.Nasir, Kamel Nafa

Sultan Qaboos University Journal For Science

We propose a generalized theory to construct higher order Grünwald type approximations for fractional derivatives. We use this generalization to simplify the proofs of orders for existing approximation forms for the fractional derivative. We also construct a set of higher order Grünwald type approximations for fractional derivatives in terms of a general real sequence and its generating function. From this, a second order approximation with shift is shown to be useful in approximating steady state problems and time dependent fractional diffusion problems. Stability and convergence for a Crank-Nicolson type scheme for this second order approximation are analyzed and are supported …

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Heat Transfer In Fe3o4-H2o Nanofluid Contained In A Triangular Cavity Under A Sloping Magnetic Field, Mohammad M.Rahman Apr 2025

Heat Transfer In Fe3o4-H2o Nanofluid Contained In A Triangular Cavity Under A Sloping Magnetic Field, Mohammad M.Rahman

Sultan Qaboos University Journal For Science

Numerical simulation is performed to explore the convective heat transfer characteristics of Fe3O4-H2O nanofluid contained in a right-angle triangular cavity considering three types of thermal boundary conditions at the bottom wall. No heat is allowed to escape through the insulated vertical wall, whereas the inclined wall is kept colder than the bottom one. A sloping magnetic field whose strength is unvarying acts upon the cavity. The physical model is converted to the mathematical form through coupled highly nonlinear partial differential equations. These equations are then transformed into the non-dimensional form with the help of a group of transformations of variables. …

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Development Of A Mathematical Model For Simulation Of Macroalgae Farming In The Coastal Areas, Abdolmajid Lababpour Apr 2025

Development Of A Mathematical Model For Simulation Of Macroalgae Farming In The Coastal Areas, Abdolmajid Lababpour

Sultan Qaboos University Journal For Science

A mathematical model consisting of a system of three coupled partial differential equations (PDEs) was proposed to estimate the concentrations of nitrogen, phosphorous and macroalgae biomass in coastal open waters. However, some simplifying assumptions were used in the model to cope with the complexity of real conditions. For the macroalgae biomass, the system works as a batch mode, while input and output were accounted for nitrogen and phosphorous. The MATLAB pdepe feature, applying the finite element method was used in model solving and the simulation of model equations. The program was split into four functions that included the solver and …

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Inequalities Concerning The Growth Of Polynomials, Bashir A.Zargar, Ahmad W.Manzoor Apr 2025

Inequalities Concerning The Growth Of Polynomials, Bashir A.Zargar, Ahmad W.Manzoor

Sultan Qaboos University Journal For Science

In this paper we consider a polynomial having no zeros in the disk . We investigate the dependence of on and obtain a refinement of a famous result due to Rivilin ([5], [7]). Our results not only generalize some polynomial inequalities but also refine a result by Aziz [1].

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Luminol Chemiluminescence Catalyzed By Silver Nanoparticles For The Sensitive Determination Of Penicillamine, Fakhr Eldin O. Suliman, Kauther Al-Hadhrami Apr 2025

Luminol Chemiluminescence Catalyzed By Silver Nanoparticles For The Sensitive Determination Of Penicillamine, Fakhr Eldin O. Suliman, Kauther Al-Hadhrami

Sultan Qaboos University Journal For Science

A sequential injection method for the determination of penicillamine (PA) was developed based on quenching the chemiluminescence generated by oxidation of luminol by hydrogen peroxide in presence of silver nanoparticles (AgNPs). The chemiluminescence (CL) of the reaction was found to greatly enhance in presence of AgNPs due to the increased catalyst surface area. The method was sensitive and found suitable for analysis of penicillamine in pharmaceutical preparations. Linear calibration curve is obtained in the range 0.2-1.0 mg mL-1 with a relative standard deviation less than 2%. A recovery percent of 102.3 ±0.2 was obtained with the tablets matrix indicating reasonable …

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Engineering Properties Of Volcanic Tuff From The Western Part Of Yemen, Adnan A. Barahim, Ibrahim A. Al-Akhaly, Is'haq R. Shamsan Apr 2025

Engineering Properties Of Volcanic Tuff From The Western Part Of Yemen, Adnan A. Barahim, Ibrahim A. Al-Akhaly, Is'haq R. Shamsan

Sultan Qaboos University Journal For Science

This paper deals with a study of the physical and mechanical characteristics of volcanic tuff and ignimbrite from six quarries located at different areas in the western part of Yemen (Manakha, Jahran, Bakhran, Dar Al-Hanash, Abaser and Soraifa). In the region, volcanic tuffs and ignimbrite are locally known by their location names and have been used as solid masonry and cladding stones. All the investigated pyroclastic rocks belong to the Tertiary volcanic. The standard physical and mechanical tests (void ratio, porosity, density, specific gravity, water absorption, uniaxial compressive strength and tensile strength) were carried out on the tuff and ignimbrite …

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Synthesis And Coordination Chemistry Of Boron-Functionalized Poly(Pyrazolylpyridyl)Borate With Ln(Iii) Metals, Nawal Al-Rasbi, Michael David D.Ward Apr 2025

Synthesis And Coordination Chemistry Of Boron-Functionalized Poly(Pyrazolylpyridyl)Borate With Ln(Iii) Metals, Nawal Al-Rasbi, Michael David D.Ward

Sultan Qaboos University Journal For Science

A new family of lanthanide/boron-based complexes have been synthesized from the novel substituted poly(pyrazolylpyridyl)borate ligand containing phenyl substituents on the boron atom Ph2Bppy (L). The complexes have been fully characterized by analytical and spectroscopic methods. The single crystal X-ray structure and mass spectroscopy reveal the isostructural dinuclear complexes: [Ln2(L)2(NO3)2(OH)2] where Ln = Eu, Gd or Tb. Upon excitation of the Ln(III) complexes in DCM, their luminescence spectra display narrow f–f transitions. It is found that the ligand can efficiently sensitize the Tb(III) complex because of the better triplet state energy match to the Tb(III)–5D0 excited states.

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Approximation Properties Of De La Vallée-Poussin Sums In Morrey Spaces, Ahmed Kinj, Mohammad Ali, Suleiman Mahmoud Apr 2025

Approximation Properties Of De La Vallée-Poussin Sums In Morrey Spaces, Ahmed Kinj, Mohammad Ali, Suleiman Mahmoud

Sultan Qaboos University Journal For Science

In this paper, we investigate the problem of the deviation of a function from its de la Vallée-Poussin sums of Fourier series in Morrey spaces defined on the unite circle in terms of the best approximation to . Moreover, approximation properties of de la Vallée-Poussin sums of Faber series in Morrey-Smirnov classes of analytic functions, defined on a simply connected domain bounded by a curve satisfying Dini's smoothness condition are obtained.

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An Evaluation Of The Mathematics Foundation Course In Sultan Qaboos University: Does High School Performance Matter?, Mohammad Mazharul Islam, Asma Al-Ghassani, Ahmed Y.S. Al-Hadhrami Apr 2025

An Evaluation Of The Mathematics Foundation Course In Sultan Qaboos University: Does High School Performance Matter?, Mohammad Mazharul Islam, Asma Al-Ghassani, Ahmed Y.S. Al-Hadhrami

Sultan Qaboos University Journal For Science

Although the mathematics foundation program was introduced in Sultan Qaboos University (SQU) half a decade ago, there has been no evaluation or assessment of the program. The aim of this study was to evaluate the students’ performance in the Mathematics foundation course in SQU and to examine the predictive value of a student’s high school performance for success in the math foundation course. The study considered a sample of 551 students who took the math course (MATH2107) during 2014 Spring semester. More than 95% of the students were admitted to SQU with a high school score of 80 and above. …

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