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Reduction Of Linear Functional Systems Using Fuhrmann's Equivalence, Mohamed S. Boudellioua Apr 2025

Reduction Of Linear Functional Systems Using Fuhrmann's Equivalence, Mohamed S. Boudellioua

Sultan Qaboos University Journal For Science

Functional systems arise in the treatment of systems of partial differential equations, delay-differential equations, multidimensional equations, etc. The problem of reducing a linear functional system to a system containing fewer equations and unknowns was first studied by Serre. Finding an equivalent presentation of a linear functional system containing fewer equations and fewer unknowns can generally simplify both the study of the structural properties of the linear functional system and of different numerical analysis issues, and it can sometimes help in solving the linear functional system. In this paper, Fuhrmann's equivalence is used to present a constructive result on the reduction …

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Thermal And Transport Properties Of Mafic And Ultramafic Rocks Of Oman Ophiolite, Sayyadul Arafin, Ram N. Singh Apr 2025

Thermal And Transport Properties Of Mafic And Ultramafic Rocks Of Oman Ophiolite, Sayyadul Arafin, Ram N. Singh

Sultan Qaboos University Journal For Science

Thermal and other physical properties of rocks and minerals are of considerable significance for deriving mineralogical and compositional models of the Earth's mantle. We have determined these properties for the mafic rock such as gabbro and ultramafic rock like harzburgite of the Oman ophiolite suite by utilizing the Debye characteristic property ,Θ-

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Energy Management Through Heat Integration: A Simple Algorithmic Approach For Introducing Pinch Analysis, Nasser A. Al-Azri Apr 2025

Energy Management Through Heat Integration: A Simple Algorithmic Approach For Introducing Pinch Analysis, Nasser A. Al-Azri

Sultan Qaboos University Journal For Science

Pinch analysis is a methodology used for minimizing energy and material consumption in engineering processes. It features the identification of the pinch point and minimum external resources. Two common established approaches are used to identify these features: the graphical approach and the algebraic method, which are time-consuming and susceptible to human and calculation errors when used for a large number of process streams. This paper presents an algorithmic procedure to heat integration based on the algebraic approach. The algorithmic procedure is explained in a didactical manner to introduce pinch analysis for students and novice researchers in the field. Matlab code …

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Numerical Wave Solutions For Nonlinear Coupled Equations Using Sinc-Collocation Method, Kamel Al-Khaled Apr 2025

Numerical Wave Solutions For Nonlinear Coupled Equations Using Sinc-Collocation Method, Kamel Al-Khaled

Sultan Qaboos University Journal For Science

In this paper, numerical solutions for nonlinear coupled Korteweg-de Vries(abbreviated as KdV) equations are calculated by the Sinc-collocation method. This approach is based on a global collocation method using Sinc basis functions. The first step is to discretize time derivative of the KdV equations by a classic finite difference formula, while the space derivatives are approximated by a weighted scheme. Sinc functions are used to solve these two equations. Soliton solutions are constructed to show the nature of the solution. The numerical results are shown to demonstrate the efficiency of the newly proposed method.

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A Note On Using Partitioning Techniques For Solving Unconstrained Optimization Problems On Parallel Systems, Mehiddin Al-Baali, Chefi Triki Apr 2025

A Note On Using Partitioning Techniques For Solving Unconstrained Optimization Problems On Parallel Systems, Mehiddin Al-Baali, Chefi Triki

Sultan Qaboos University Journal For Science

We deal with the design of parallel algorithms by using variable partitioning techniques to solve nonlinear optimization problems. We propose an iterative solution method that is very efficient for separable functions, our scope being to discuss its performance for general functions. Experimental results on an illustrative example have suggested some useful modifications that, even though they improve the efficiency of our parallel method, leave some questions open for further investigation.

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A Priori Error Estimates For Mixed Finite Element Schemes For The Wave Equation, Samir Karaa Apr 2025

A Priori Error Estimates For Mixed Finite Element Schemes For The Wave Equation, Samir Karaa

Sultan Qaboos University Journal For Science

A family of implicit-in-time mixed finite element schemes is presented for the numerical approximation of the acoustic wave equation. The mixed space discretization is based on the displacement form of the wave equation and the time-stepping method employs a three-level one-parameter scheme. A rigorous stability analysis is presented based on energy estimation and sharp stability results are obtained. A convergence analysis is carried out and optimal a priorierror estimates for both displacement and pressure are derived.

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Effect Of Perpendicular Magnetic Field On Free Convection In A Rectangular Cavity, Anand Kumar, Ashok K. Singh, Pallath Chandran, Nirmal C. Sacheti Apr 2025

Effect Of Perpendicular Magnetic Field On Free Convection In A Rectangular Cavity, Anand Kumar, Ashok K. Singh, Pallath Chandran, Nirmal C. Sacheti

Sultan Qaboos University Journal For Science

The steady free convective flow of a viscous incompressible and electrically conducting fluid in a two-dimensional cavity in the presence of a magnetic field applied normal to the plane of the cavity is investigated. The side vertical walls of the cavity are heated differentially while the horizontal walls are assumed to be insulated. The governing equations are re-formulated in terms of vorticity and stream function. The resulting boundary value problem is solved numerically using an alternating direction implicit (ADI) method. A number of plots illustrating the influence of Hartmann number and Rayleigh number on the streamlines and isotherms as well …

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Mapping Methods To Solve A Modified Korteweg-De Vries Type Equation, Edamana. V. Krishnan Apr 2025

Mapping Methods To Solve A Modified Korteweg-De Vries Type Equation, Edamana. V. Krishnan

Sultan Qaboos University Journal For Science

In this paper, we employ mapping methods to construct exact travelling wave solutions for a modified Korteweg-de Vries equation. We have derived periodic wave solutions in terms of Jacobi elliptic functions, kink solutions and singular wave solutions in terms of hyperbolic functions.

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Rolling Optimization Method For Humanoid Robots, Riadh Zaier Apr 2025

Rolling Optimization Method For Humanoid Robots, Riadh Zaier

Sultan Qaboos University Journal For Science

In this paper, a method of optimizing the rolling amplitude needed for a stable and smooth walking movement of a humanoid robot is considered. The optimization algorithm was based on minimizing a cost function defined by the rolling overshoot. The amplitude of the rolling during locomotion was calculated using the lateral zero moment point (ZMP) position. The initial value of the rolling was the static rolling that corresponds to the position of the ZMP at the center of the support polygon. The algorithm consisted of performing a ZMP calculation at two points that correspond to single support phases. Simplifying the …

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Numerical Solution To A One-Dimensional, Nonlinear Problem Of Thermoelasticity With Volume Force And Heat Supply In A Slab, Wael M. Mohamed, Ahmed F. Ghaleb, Enaam K. Rawy, Hassan A.Z. Hassan, Adel A. Mosharafa Apr 2025

Numerical Solution To A One-Dimensional, Nonlinear Problem Of Thermoelasticity With Volume Force And Heat Supply In A Slab, Wael M. Mohamed, Ahmed F. Ghaleb, Enaam K. Rawy, Hassan A.Z. Hassan, Adel A. Mosharafa

Sultan Qaboos University Journal For Science

A numerical solution is presented for a one-dimensional, nonlinear boundary-value problem of thermoelasticity with variable volume force and heat supply in a slab. One surface of the body is subjected to a given periodic displacement and Robin thermal condition, while the other is kept fixed and at zero temperature. Other conditions may be equally treated as well. The volume force and bulk heating simulate the effect of a beam of hot particles infiltrating the medium. The present study is a continuation of previous work by the same authors for the half-space [1]. The presented Figures display the process of propagation …

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Antibacterial And Antifungal Activities Of Cyanobacterial Strains Isolated From Hot Springs In Oman, Neelam Sherwani1, Raeid M.M. Abed, Sergey Dobretsov, Sheji Mary Apr 2025

Antibacterial And Antifungal Activities Of Cyanobacterial Strains Isolated From Hot Springs In Oman, Neelam Sherwani1, Raeid M.M. Abed, Sergey Dobretsov, Sheji Mary

Sultan Qaboos University Journal For Science

In this study, cyanobacterial microbial mats from five hot springs in Oman, namely Al Kasfah Rustaq, Al Thwara Nakhl, Al–Ali Hammam, Gala and Bowsher, were characterized using direct microscopy. Nine monoclonal cyanobacterial cultures were obtained and their extracts in butanol, dichloromethane (DCM) and hexane were screened for antibacterial and antifungal activities. Direct microscopy revealed the presence of 12 different unicellular and filamentous morphotypes, with different distribution in the various mats. Temperature seems to be one of the most important parameters that accounts for the differences in cyanobacterial composition of the mats. Cells of the nine isolates and their aqueous supernatants …

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Histopathological And Ultrastructural Changes In The Liver And Gills Of The Killifish Aphanius Dispar (Cyprinodontidae) Exposed To Aflatoxin B1, Horiya H. Al-Azri, Taher Ba-Omar, Abdulkadir Elshafie, Michael J. Barry Apr 2025

Histopathological And Ultrastructural Changes In The Liver And Gills Of The Killifish Aphanius Dispar (Cyprinodontidae) Exposed To Aflatoxin B1, Horiya H. Al-Azri, Taher Ba-Omar, Abdulkadir Elshafie, Michael J. Barry

Sultan Qaboos University Journal For Science

Aflatoxin B1 (AFB1) is a mycotoxin which can cause serious toxicity to animals and humans. The aim of this study was to investigate the effects of AFB1 in Aphanius dispar fish and measure residues in tissues after in vivo exposure. Aphanius dispar were fed diets containing 50, 100, 150 and 200 µg AFB1/kg for 10, 20 and 30 days. At the end of the experiment, the liver and gills were dissected out and processed for light and electron microscopy. During the experiment, no external changes or unusual behavior were observed in the fish. Histopathological and ultrastructural changes in liver appeared …

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Synthesis And Characterization Of Some Macrocylic Complexes Incorporating Indole And 2,2'-Bipyridine Or 1,10-Phenanthroline, Muhammad S. Khan, Nawal K. Al-Rasbi, Edwin C. Constable Apr 2025

Synthesis And Characterization Of Some Macrocylic Complexes Incorporating Indole And 2,2'-Bipyridine Or 1,10-Phenanthroline, Muhammad S. Khan, Nawal K. Al-Rasbi, Edwin C. Constable

Sultan Qaboos University Journal For Science

Complexes of anionic pentadentate macrocyclic ligands by the template condensation of bis(hydrazino)2,2'-bipyridine or 1,10-phenanthroline with an indoledialdehyde have been synthesized. The new Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II) macrocyclic complexes have been characterized by analytical and spectroscopic techniques and by conductivity and magnetic susceptibility measurements.

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An Efficient Parallel Gauss-Seidel Algorithm On A 3d Torus Network-On-Chip, Khaled Day, Mohammad H. Al-Towaiq Apr 2025

An Efficient Parallel Gauss-Seidel Algorithm On A 3d Torus Network-On-Chip, Khaled Day, Mohammad H. Al-Towaiq

Sultan Qaboos University Journal For Science

Network-on-chip (NoC) multi-core architectures with a large number of processing elements are becoming a reality with the recent developments in technology. In these modern systems the processing elements are interconnected with regular NoC topologies such as meshes and tori. In this paper we propose a parallel Gauss-Seidel (GS) iterative algorithm for solving large systems of linear equations on a 3-dimensional torus NoC architecture. The proposed parallel algorithm is O(Nn2/k3) time complexity for solving a system with a matrix of order n on a k×k×k 3D torus NoC architecture with N iterations assuming n and N are large compared to k. …

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Mobilization And Redistribution Of Elements In Laterites Of Semail Ophiolite, Oman: A Mass Balance Study, Salah Al Khirbash, Khadija Semhi Apr 2025

Mobilization And Redistribution Of Elements In Laterites Of Semail Ophiolite, Oman: A Mass Balance Study, Salah Al Khirbash, Khadija Semhi

Sultan Qaboos University Journal For Science

Several samples of laterites were collected from four paleosol profiles, Ibra, East Ibra, Al-Russayl, and Tiwi representing the vertical lithological variation within each profile. The mineralogical and geochemical composition of laterites in every section revealed differences in thickness and redistribution of elements reflecting different conditions of weathering processes. Elemental mass balance was calculated for every profile relative to the parent rock. The results indicated redistribution of elements from the surface to deeper zones with an enrichment of elements in the saprolite and oxide zones. Among the different sections, the profile of East Ibra composite 1 and 2 is characterized by …

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Investigation Of The Direction Of Spontaneous Magnetisation At 0 K In Hoco2 And Tmfe2, Carlo Carboni, Eman Al-Abri Apr 2025

Investigation Of The Direction Of Spontaneous Magnetisation At 0 K In Hoco2 And Tmfe2, Carlo Carboni, Eman Al-Abri

Sultan Qaboos University Journal For Science

The direction of spontaneous magnetisation at 0 K across a phase orientation boundary in rare-earth laves phase compounds is computed as a function of the ratio of magnetic to electrostatic interactions. The phase boundary and range of parameters used for the computation correspond to the portion of the orientational phase diagram where experimental data can be obtained. In the series of pseudo-binary compounds (Gdx Ho1-x )Co2 and (Yx Ho1-x )Co2 the range of parameters covers the continuous transition from the <100> to the <110> orientations. The nmr measurements on this series show that the direction of spontaneous magnetisation is at intermediate orientation …

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A Unique Common Coupled Fixed Point Theorem For Four Maps In Partial B-Metric-Like Spaces, Mohammad S. Khan, Konduru P.R. Rao, Kandipalli V.S. Parvathi Apr 2025

A Unique Common Coupled Fixed Point Theorem For Four Maps In Partial B-Metric-Like Spaces, Mohammad S. Khan, Konduru P.R. Rao, Kandipalli V.S. Parvathi

Sultan Qaboos University Journal For Science

We prove the existence of a unique common coupled fixed point theorem for four mappings satisfying a general contractive condition on partial b-metric-like spaces. We also give an example to illustrate our main theorem. Our theorem generalizes and improves the theorem of [1].

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Spin Torque Oscillator For High Performance Magnetic Memory, Rachid Sbiaa, Khaled Bouziane Apr 2025

Spin Torque Oscillator For High Performance Magnetic Memory, Rachid Sbiaa, Khaled Bouziane

Sultan Qaboos University Journal For Science

A study on spin transfer torque switching in a magnetic tunnel junction with perpendicular magnetic anisotropy is presented. The switching current can be strongly reduced under a spin torque oscillator (STO), and its use in addition to the conventional transport in magnetic tunnel junctions (MTJ) should be considered. The reduction of the switching current from the parallel state to the antiparallel state is greater than in the opposite direction, thus minimizing the asymmetry of the resistance versus current in the hysteresis loop. This reduction of both switching current and asymmetry under a spin torque oscillator occurs only during the writing …

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Crystal Field Parameters And Optical Parameters Of Nd3+ In Sodium Bismuth Silicate Glass, Vinoy Thomas, Ramakrishna P.G.P.S. Sofin, Mathew Allen, Hysen Thomas Apr 2025

Crystal Field Parameters And Optical Parameters Of Nd3+ In Sodium Bismuth Silicate Glass, Vinoy Thomas, Ramakrishna P.G.P.S. Sofin, Mathew Allen, Hysen Thomas

Sultan Qaboos University Journal For Science

Neodymium doped sodium bismuth silicate glasses were prepared by the melt quench technique. Optical absorption spectra of the Nd3+ion in the present glassy systems were recorded in the UV-Vis-NIR region. Taylor series expansion method was adopted for theoretical evaluation of various crystal field parameters such as the Slater-Condon (F2,F4,F6), spin orbit and Racah parameters (E1,E2,E3). Oscillator strength and electric dipole line strength of the observed transitions were evaluated with the help of Judd-Ofelt (JO) theory. Radiative transition probability (A), total radiative transition probability (At), radiative life time (trad), branching ratios (b) and integrated absorption (sa) cross section for stimulated emission …

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Determinants Of Contraceptive Practice In Oman By Using Multilevel Modeling, Moza S. Al-Balushi, Mohammed S. Ahmed, M. Mazharul Islam Apr 2025

Determinants Of Contraceptive Practice In Oman By Using Multilevel Modeling, Moza S. Al-Balushi, Mohammed S. Ahmed, M. Mazharul Islam

Sultan Qaboos University Journal For Science

In this paper, multilevel logistic regression models are developed for examining the hierarchical effects of contraceptive use and its selected determinants in Oman using the 2008 Oman National Reproductive Health Survey (ONRHS). Comparison between single level and multilevel logistic regression models has been made to examine the plausibility of multilevel effects of contraceptive use. From the multilevel logistic regression model analysis, it was found that there is real multilevel variation among contraceptive users in Oman. The results indicate that a multilevel logistic regression model is the best fit over ordinary multiple logistic regression models. Generally, this study revealed that women’s …

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The Influence Of Diets Containing Phenols And Condensed Tannins On Protein Picture, Clinical Profile And Rumen Characteristics In Omani Sheep, Osman Mahgoub, Isam T.Kadim, Hamza A. Babiker, Mohammed N. Al-Kindi Apr 2025

The Influence Of Diets Containing Phenols And Condensed Tannins On Protein Picture, Clinical Profile And Rumen Characteristics In Omani Sheep, Osman Mahgoub, Isam T.Kadim, Hamza A. Babiker, Mohammed N. Al-Kindi

Sultan Qaboos University Journal For Science

A study was carried out to investigate the effects of feeding low quality non-conventional feeds (NCF) containing phenols and condensed tannins on health and performance characteristics in Omani sheep. Twelve Omani sheep were fed one of two base roughages, urea-treated palm frond (UTPF) or Rhodesgrass hay, (RGH) plus a commercial concentrate for 63 days. Haematological, serum biochemical and urine analyses were used to assess sheep health. Serum protein fractions were measured using electrophoresis. Urea-treated palm frond contained higher levels of polyphenols and condensed tannins and fiber than Rhodesgrass hay or concentrate feed. Animals fed UTPF had lower feed intake (P<0.05) and lower body gain (P<0.001) than those fed RGH. Rumen liquor of UTPF-fed animals had higher pH, ammonia-nitrogen and butyric fatty acid but lower acetic fatty acid (P<0.05). Animals fed UTPF had higher neutrophil (P<0.05) but lower lymphocyte (P<0.05) and monocyte (P<0.001) counts by the end of the trial than those fed RGH. There were no effects of diet on serum albumin or globulin fraction levels or albumin:globulin ratio. There were no major effects on urine analysis but there was a trend by control animals to have higher protein and specific gravity than treated ones. This study indicated that feeding low quality non-conventional feeds containing polyphenols or tannins would reduce body gain and may produce some effects on clinical parameters. Although tannins are known to influence protein digestion and absorption in ruminants, it did not significantly affect the serum protein picture in sheep.

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A Simple Surfactant-Free Solution Phase Synthesis Of Flower-Like In2s3 Hierarchitectures And Their Photocatalytic Activities, Rengaraj Selvaraj, Kezhen Qi, Uiseok Jeong, Kholood Al Nofli, Salma Al-Kindy, Mika Sillanpää, Younghun Kim Apr 2025

A Simple Surfactant-Free Solution Phase Synthesis Of Flower-Like In2s3 Hierarchitectures And Their Photocatalytic Activities, Rengaraj Selvaraj, Kezhen Qi, Uiseok Jeong, Kholood Al Nofli, Salma Al-Kindy, Mika Sillanpää, Younghun Kim

Sultan Qaboos University Journal For Science

Flower-like In2S3 hierarchical nanostructures were successfully prepared via a facile solution-phase route, using thiacetamide as both sulfur source and capping agent. Our experimental results demonstrated that the morphology of these In2S3 nanostructures can be easily modified by changing the ratio of In(NO3)3/thiacetamide. With the ratio increasing from 1:1.5 to 1:6, the In2S3 crystals exhibited flower-like morphology of varying size. XRD and HRTEM of the flowers revealed the cubic structure of In2S3; morphological studies examined by SEM and TEM showed that the synthesized In2S3 nanostructure was a flower-like hierarchitecture assembled from nanoscale flakes. XPS and EDX analysis confirmed the stoichiometry of …

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The Effect Of Salinity On Solamargine And Solasonine Contents Of Solanum Incanum Plants Grown In Oman, Sana S. Al Sinani, Elsadig A. Eltayeb Apr 2025

The Effect Of Salinity On Solamargine And Solasonine Contents Of Solanum Incanum Plants Grown In Oman, Sana S. Al Sinani, Elsadig A. Eltayeb

Sultan Qaboos University Journal For Science

In addition to its traditional medicinal importance, Solanum incanum (thorn apple) is also a rich source of important cytotoxic glycoalkaloids such as solamargine and solasonine. The effect of salinity stress on solamargine and solasonine production by Solanum incanum plants grown in soil has been investigated. Salinity stress has been applied by adding NaCl to the soil, in concentrations: 0.0 (control), 75, 150, and 225 mM for 8 weeks. HPTLC method was used for analysis of solamargine and solasonine in leaves, stem and roots. A positive correlation was observed between 150 mM NaCl salinity and production of solamargine and solasonine in …

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Facile And Surfactant-Free Synthesis Of Hierarchical Zno Microstructures, Kezhen Qi, Ruidan Wang, Jiaqi Fu, Ke Chen, Chunying Zuo Apr 2025

Facile And Surfactant-Free Synthesis Of Hierarchical Zno Microstructures, Kezhen Qi, Ruidan Wang, Jiaqi Fu, Ke Chen, Chunying Zuo

Sultan Qaboos University Journal For Science

Hierarchical ZnO crystals with flower-like microstructures were successfully synthesized via a facile hydrothermal route without using any surfactants. The morphology of these microstructures can be easily controlled by adjusting the pH of the reaction solution. The products were characterized by X-ray powder diffraction (XRD) and scanning electron microscope (SEM). Furthermore, a possible growth mechanism of ZnO hierarchical microstructures was proposed.

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Dioxygen Binding By Cobalt(Ii) Complexes Of 8,8'-Bis(Aminomethyl)-2,2'-Biquinoline, Muhammad S. Khan, Nawal K. Al-Rasbi, Edwin C.Constable Apr 2025

Dioxygen Binding By Cobalt(Ii) Complexes Of 8,8'-Bis(Aminomethyl)-2,2'-Biquinoline, Muhammad S. Khan, Nawal K. Al-Rasbi, Edwin C.Constable

Sultan Qaboos University Journal For Science

A new series of Co(II) complexes of the type CoLX2 , where Lis a tetra-dentate ligand 8,8'-bis(aminomethyl)-2,2'-biquinoline and X= SCN–, BF4–, I– or NO3– , have been synthesized and characterized. The complexes have magnetic moments in the range typical of a low-spin d7 Co(II) center. The interaction of these Co(II) complexes with dioxygen was studied by E.S.R. spectroscopy. A dicobalt(III) peroxo-bridged complex was formed in DMF solution, associated with the formation of an E.S.R.-silent solution compatible with the formation of low-spin d6 Co(III) species. Similar behavior was also observed for the interaction of these Co(II) complexes with dioxygen in the …

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Recognition Of Minerals Using Multispectral Remote Sensing Data: A Case Study In The Sultanate Of Oman, Sankaran Rajendran, Sobhi Nasir Apr 2025

Recognition Of Minerals Using Multispectral Remote Sensing Data: A Case Study In The Sultanate Of Oman, Sankaran Rajendran, Sobhi Nasir

Sultan Qaboos University Journal For Science

The present study demonstrates the capability of a multispectral sensor for the detection of the minerals in the rocks surrounding the Rusayl and Al Jafnayn regions, Sultanate of Oman. The study of spectral absorptions of rocks and minerals in the visible and near infrared (VNIR) and short wavelength infrared (SWIR) spectral bands of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) using the Spectral Angle Mapper (SAM) supervised image classification technique has provided information on the occurrence of minerals in the rock types of the regions. The study shows the occurrence of carbonate minerals in the limestone formations and …

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Some Improved Estimators In Double Sampling Using Two Auxiliary Variables, Mohammad S. Ahmed Apr 2025

Some Improved Estimators In Double Sampling Using Two Auxiliary Variables, Mohammad S. Ahmed

Sultan Qaboos University Journal For Science

Dash and Mishra [1] suggested an improved class of estimators without defining the optimum estimator. However, they gave the wrong Taylor’s series expression of their class of estimator and their minimum mean squared error expressions are also incorrect. Here we show that Ahmed et al.’s [2] class of chain estimators is more efficient than Dash and Mishra’s [1], with minimum mean squared error.

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Hydromagnetic Boundary Layer Flow And Heat Transfer Characteristics Of A Nanofluid Over An Inclined Stretching Surface In The Presence Of A Convective Surface: A Comprehensive Study, Mohammad M. Rahman, Mohammed M. Al-Hatmi Apr 2025

Hydromagnetic Boundary Layer Flow And Heat Transfer Characteristics Of A Nanofluid Over An Inclined Stretching Surface In The Presence Of A Convective Surface: A Comprehensive Study, Mohammad M. Rahman, Mohammed M. Al-Hatmi

Sultan Qaboos University Journal For Science

In this paper we investigate numerically the hydromagnetic boundary layer flow and heat transfer characteristics of a nanofluid using three types of nanoparticles (copper, aluminium oxide and titanium dioxide) having various shapes (spherical, cylindrical, arbitrary, etc) by considering three kinds of base fluids (water, ethylene glycol and engine oil) over a nonlinear inclined stretching surface, taking into account the effect of convective surface condition. Using similarity transformations, the governing nonlinear partial differential equations of the physical model are transformed into non-dimensional ordinary differential equations which are solved for local similar solutions using the very robust computer algebra software, Maple 13. …

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Projection Of Polyhedra Onto Coxeter Planes Described With Quaternions, Mudhahir Al-Ajmi, Mehmet Koca, Hashima Bait Bu Salasel Apr 2025

Projection Of Polyhedra Onto Coxeter Planes Described With Quaternions, Mudhahir Al-Ajmi, Mehmet Koca, Hashima Bait Bu Salasel

Sultan Qaboos University Journal For Science

3-dimensional convex uniform polyhedra have been projected onto their corresponding Coxeter planes defined by the simple roots of the Coxeter diagram ,

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A Test For Dominance, Atsu S.S. Dorvlo Apr 2025

A Test For Dominance, Atsu S.S. Dorvlo

Sultan Qaboos University Journal For Science

In some selection situations a simple majority is not enough to indicate that one item dominates the others. In this paper we develop a simple procedure for testing the dominance of one item with respect to others in a multi option situation. Expressions are given for computing the relevant p-values. The procedure is illustrated.

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