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The Continued Presence Of Antibiotic-Resistant Bacteria And Heavy Metals At One Of The World’S Most Important Green Turtles’ Nesting Location, Ras Al-Jinz Reserve, Oman, Al-Musharafi S.K, Al-Amrani S.A., Mahmoud I.Y, Al-Bahry S.N, Leduc A.O.H.C Apr 2025

The Continued Presence Of Antibiotic-Resistant Bacteria And Heavy Metals At One Of The World’S Most Important Green Turtles’ Nesting Location, Ras Al-Jinz Reserve, Oman, Al-Musharafi S.K, Al-Amrani S.A., Mahmoud I.Y, Al-Bahry S.N, Leduc A.O.H.C

Sultan Qaboos University Journal For Science

Environmental contamination of marine habitats is a global concern, especially in areas that are crucial for endangered species’ life cycles. To gain a comprehensive understanding of environmental contamination, analyzing various biotic and abiotic components of ecosystems is necessary. Situated in the Arabian Peninsula, Ras al-Jinz Reserve serves as an invaluable nesting site for green sea turtles (Chelonia mydas). There, the prevalence of antibiotic-resistant microbial strains and heavy metals was assessed by collecting samples from diverse components of this ecosystem, including sand from turtle nests, dead turtle hatchlings, fresh turtle eggs, oviductal fluids from nestling turtles, turtle carapace smears, live crabs, …

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Production And Optimization Of Extracellular Α-Amylase From Halophilic Bacteria Cytobacillus Oceanisediminis Isolated From Wadi-El-Natrun, Egypt, Nada A. Hashem, Naeima M.H. Yousef Apr 2025

Production And Optimization Of Extracellular Α-Amylase From Halophilic Bacteria Cytobacillus Oceanisediminis Isolated From Wadi-El-Natrun, Egypt, Nada A. Hashem, Naeima M.H. Yousef

Sultan Qaboos University Journal For Science

The current study aimed to maximize α-amylase enzyme production by halophilic bacteria Cytobacillus oceanisediminis isolated from soil of Wadi-El-Natrun, Egypt. The results showed that of 21 halophilic bacterial isolates recovered from saline soil samples, eight isolates were high amylase producers. Interestingly, the bacterial isolate AHB6 exhibited the highest extracellular amylase production and was selected for further studies. This isolate was molecularly identified based on the 16srRNA gene sequencing as Cytobacillus oceanisediminis and has the accession number OM759999. The optimum temperature for α-amylase enzyme was 45 °C and exhibited thermostability at 45 °C for 1 h and retained more than 80% …

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Lithostratigraphy And Microfacies Of The Upper Cretaceous Muti Formation Of The Oman Foreland Basin, Nakhal Area, Oman, Jenan Ahmed Attar, Iftikhar Ahmed Abbasi, Muhammad Hanif, Mohamed A.K. El-Ghali, Abdulrazaq Al-Sayigh, Abdul Rahman Al-Harthi Apr 2025

Lithostratigraphy And Microfacies Of The Upper Cretaceous Muti Formation Of The Oman Foreland Basin, Nakhal Area, Oman, Jenan Ahmed Attar, Iftikhar Ahmed Abbasi, Muhammad Hanif, Mohamed A.K. El-Ghali, Abdulrazaq Al-Sayigh, Abdul Rahman Al-Harthi

Sultan Qaboos University Journal For Science

The Upper Cretaceous Muti Formation was deposited in the Oman Foreland Basin during the obduction of the allochthonous units on the eastern margin of the Arabian Platform. The formation is exposed in various isolated outcrops around Jabal Akhdar Mountain and is located between the Mesozoic platform carbonates below and the allochthonous nappe above. The current study is the first to describe the outcrops of the Muti Formation in the Nakhal area. It focuses on the lithofacies, microfacies distribution, and the characterization of the depositional environment of the formation. The lithofacies and microfacies of the formation are described from two measured …

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Knowledge And Attitude Towards Covid-19 And Associated Mental Health Status Among Students Of Sultan Qaboos University, Oman, M Mazharul Islam, Ronald Wesonga, Iman Al Hasani, Afra Al Manei Apr 2025

Knowledge And Attitude Towards Covid-19 And Associated Mental Health Status Among Students Of Sultan Qaboos University, Oman, M Mazharul Islam, Ronald Wesonga, Iman Al Hasani, Afra Al Manei

Sultan Qaboos University Journal For Science

This study examined the COVID-19-related knowledge and attitude towards COVID-19 and associated mental health status during COVID-19 among the students of Sultan Qaboos University in Oman using an online cross-sectional survey conducted from 26 March - 25 April 2021 among the students of Sultan Qaboos University (SQU). Both descriptive and inferential statistical techniques, including multiple logistic regression analysis, were used for data analysis. Of the 1,951 respondents, 60% were females with a mean age of 22 years. About 13% were tested COVID-19 positive and 3.6% were tested positive. Overall, students demonstrated a high level (81%) of knowledge and a positive …

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Adsorption Of Methylene Blue Onto Hydrophobic Activated Carbon, El-Said Ibrahim El-Shafey, Said M. Al-Mashaikhi Apr 2025

Adsorption Of Methylene Blue Onto Hydrophobic Activated Carbon, El-Said Ibrahim El-Shafey, Said M. Al-Mashaikhi

Sultan Qaboos University Journal For Science

Activated carbon (AC) was prepared from date palm leaflets using NaOH activation. AC was oxidized using concentrated HNO3 to produce oxidized activated carbon (ON). Alkylamines including methylamine (M), dimethylamine (DM), ethylamine (E), diethylamine (DE), and diisopropylamine (DIP) were covalently immobilized onto ON to produce ONM, ONDM, ONE, ONDE, and ONDIP hydrophobic activated carbons, respectively. The surface area of AC (588 m2/g) decreased on oxidation with a further decrease on functionalization. These carbons were tested for methylene blue (MB) adsorption. Initial pH 7 was found optimum for the adsorption of MB. The hydrophobic activated carbons show faster adsorption (except for ONDE), …

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Geological Complications And Environmental Hazards Of The Cement Raw Materials Quarry Sites In Yemen, Ahmed M. Al-Anweh, Mohammed Ibrahim El-Anbaawy, Mohamed Mahmmoud Abu-Zeid, Ibrahim Al-Akhaly, S:17:"Sana'a University", } N/A Apr 2025

Geological Complications And Environmental Hazards Of The Cement Raw Materials Quarry Sites In Yemen, Ahmed M. Al-Anweh, Mohammed Ibrahim El-Anbaawy, Mohamed Mahmmoud Abu-Zeid, Ibrahim Al-Akhaly, S:17:"Sana'a University", } N/A

Sultan Qaboos University Journal For Science

Extensive field and site investigations were conducted to assess and evaluate the situation in the presently exploited quarries of cement raw materials in Yemen. These quarries have several geological complications represented mainly by high elevations, steep slopes, rugged topography, heterogeneity in bed thickness, lithologic composition and quality, presence of igneous sills and dykes, intensive fracturing and jointing and abundance of karstification features. Moreover, the processes of quarrying and related operations have several negative environmental impacts the most important of which are soil failure, overburden and land sliding, toppling and rock falls (which result in considerable mass wasting) and emission of …

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Prevalence Of Gastrointestinal Helminthes In Pigs Reared In Research Farms Of Michael Okpara University Of Agriculture, Umudike, South Eastern Nigeria, Ebube Charles Amaechi, Miracle Innocent Dike, Onyinye Mkpola Ukpai, Blessing Uzoamaka Ejike Apr 2025

Prevalence Of Gastrointestinal Helminthes In Pigs Reared In Research Farms Of Michael Okpara University Of Agriculture, Umudike, South Eastern Nigeria, Ebube Charles Amaechi, Miracle Innocent Dike, Onyinye Mkpola Ukpai, Blessing Uzoamaka Ejike

Sultan Qaboos University Journal For Science

Gastrointestinal parasitism in swine production is a world-wide problem especially in tropical resource-poor countries. These infections in animals result in significant economic losses. This study aimed to assess the prevalence and spectrum of gastrointestinal parasites of pigs reared in two research farms in Michael Okpara University of Agriculture, Umudike, South eastern Nigeria. From April, 2016 to July, 2016, 220 samples of pig faeces from two research farms (CASAP Research Farm and MOUAU Commercial Pig Farm) were analyzed using floatation and direct smear methods to identify varied parasitic stages present in the faeces. Data generated showed an overall prevalence of 64.6% …

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Development And Validation Of An Rp-Hplc-Fld Method For The Determination Of Biogenic Amines After Pre-Column Derivatization With A New Pyrazoline Based Reagent, 3- Naphthyl-1-(4-Trifluoromethyl)-5-(4-Carboxy Phenyl)-2-Pyrazoline, Salma Mohamed Al-Kindy, Amal Al Sabahi, Saleh Al-Busafi, Beena Varghese, Fakhreldin Osman Suliman Apr 2025

Development And Validation Of An Rp-Hplc-Fld Method For The Determination Of Biogenic Amines After Pre-Column Derivatization With A New Pyrazoline Based Reagent, 3- Naphthyl-1-(4-Trifluoromethyl)-5-(4-Carboxy Phenyl)-2-Pyrazoline, Salma Mohamed Al-Kindy, Amal Al Sabahi, Saleh Al-Busafi, Beena Varghese, Fakhreldin Osman Suliman

Sultan Qaboos University Journal For Science

Application of 3-Naphthyl-1-(4-trifluoromethyl)-5-(4-carboxy phenyl)-2-pyrazoline (NFCP) as a novel fluorigenic label for the derivatization of biogenic amines (BAs) and separation by liquid chromatography (LC) was investigated. Optimum conditions for the pre-column derivatization and chromatographic separation were investigated. The resulting derivatives are fluorescent at λex/λem: 380/460 nm. For the sake of evaluating the efficacy of the proposed analysis of BAs of different nature, the formation of nine NFCP-BAs derivatives was tested individually. Simultaneous derivatization and separation of four BAs (histamine, tyramine, tryptamine, and phenylethylamine) were achieved under the isocratic elution mode. Furthermore, the derivatives were identified by the characteristic product ion obtained …

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Green Preparation Of Aluminum-Based Metal-Organic Framework (Al-Mof) From Waste Plastic Bottles And Waste Aluminum Scraps, Saleh N. Al-Busafi Apr 2025

Green Preparation Of Aluminum-Based Metal-Organic Framework (Al-Mof) From Waste Plastic Bottles And Waste Aluminum Scraps, Saleh N. Al-Busafi

Sultan Qaboos University Journal For Science

The vast use of polyethylene terephthalate (PET) drinking water bottles has increased dramatically worldwide in recent decades, inflicting severe consequences on the environment. According to the latest survey, a million plastic bottles are bought around the globe every minute. The non-biodegradable nature of PET materials has led to a huge accumulation of plastic in waste landfills. Among the current recycling methods used to solve this environmental problem is chemical recycling. In this method, PET bottles are converted back cleanly into their starting materials: terephthalic acid and ethylene glycol. This paper unveils the exploitation of recycling products from PET bottles and …

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Delineation Of Weathered Layer Using Uphole And Surface Seismic Refraction Methods In Parts Of Niger Delta, Nigeria, Mfoniso Aka, Okechukwu Agbasi Apr 2025

Delineation Of Weathered Layer Using Uphole And Surface Seismic Refraction Methods In Parts Of Niger Delta, Nigeria, Mfoniso Aka, Okechukwu Agbasi

Sultan Qaboos University Journal For Science

Uphole and surface seismic refraction surveys were carried out in parts of the Niger Delta, Nigeria, to delineate weathering thickness and velocity associated with aweathered layer. A total of twelve uphole and surface seismic refraction surveyswere shot, computed and analyzed. The velocity of the uphole seismic refraction ranged from 344.8 to 680.3 m/s with a thickness of 5.45 to 13.35 m. Surface seismic refraction ranged from 326.6 to 670.2 m/s and 4.30 to 12.0 m, respectively. The average velocity and thickness ranged from 559.6 to 548.0 m/s and 9.43 to 8.63m with differences of 11.6 m/s and 0.83 m respectively. …

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Effects Of Thermal Stratification And Anisotropic Porous Material In A Symmetrically Heated Vertical Channel, Basant K. Jha, Muhammad K. Musa, Abiodun O. Ajibade Apr 2025

Effects Of Thermal Stratification And Anisotropic Porous Material In A Symmetrically Heated Vertical Channel, Basant K. Jha, Muhammad K. Musa, Abiodun O. Ajibade

Sultan Qaboos University Journal For Science

The coexistence in nature of thermally stratified fluids and directionally inclined porous structures abound in geophysical fluid flow. Despite their important applications especially in underground flow, their combined effects on natural convection have not been intensively investigated. This article aims to investigate a fully developed time dependent natural convection of viscous incompressible stably stratified fluid in the presence of anisotropic porous material. The semi analytical solutions of the governing equations for the temperature and velocity fields are obtained using the Laplace Transform Technique, Riemann Sum Approximation and D’Alembert Methods. The choice of the D’Alembert Method is to provide a systematic …

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Flora, Life-Forms And Biological Spectrum Of Muscat Governorate, Neelam Sherwani Apr 2025

Flora, Life-Forms And Biological Spectrum Of Muscat Governorate, Neelam Sherwani

Sultan Qaboos University Journal For Science

The present study evaluated the floristic diversity and biological spectrum of Muscat Governorate, Sultanate of Oman. Heterogeneity of geology, topography and climatic conditions create a diverse array of habitats across the 3,500 km2 study area, supporting a range of vegetation types. Floristic studies were conducted across 42 sites spread across various habitats such as sand dunes, alluvial plains, gravel plains, wadis, saline dunes, coastal areas, farms and plantations. A total of 264 species belonging to 183 genera and 54 families of angiosperm were documented during sampling the vegetation from different wilayats of the Governorate. Maximum number of species belonged to …

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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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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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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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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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Study On The Reactivity Of Amino Acid Chemosensor, Npfnp, With Ethanol: Structural Elucidation Through Single Crystal Xrd And Dft Calculations, Beena Varghese, Saleh N. Al-Busafi, Fakhr Eldin O. Suliman, Salma Al-Kindy Apr 2025

Study On The Reactivity Of Amino Acid Chemosensor, Npfnp, With Ethanol: Structural Elucidation Through Single Crystal Xrd And Dft Calculations, Beena Varghese, Saleh N. Al-Busafi, Fakhr Eldin O. Suliman, Salma Al-Kindy

Sultan Qaboos University Journal For Science

A novel ethoxy derivative of an amino acid chemosensor, 3-naphthyl-1-phenyl-5-(2ʹ-fluoro-5ʹ-nitrophenyl)-2-pyrazoline (NPFNP), has been synthesized and characterized by different spectroscopic methods. A single crystal of the ethoxy derivative, 3-naphthyl-1-phenyl-5-(2ʹ-ethoxy-5ʹ-nitrophenyl)-2-pyrazoline NPENP, has been obtained and characterized. The structure holds interest as it carries biologically active pyrazoline as a central ring attaching to electron donating and withdrawing substituents. The major motivation for this work was to gain detailed insight into the structural parameters of this compound for investigating the influence of crystal packing and geometrical dimensions on optical properties. Time-dependent DFT calculations have been employed for comparing the XRD data with theoretical parameters. …

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Review Of The Sayh Al Uhaymir (Sau) 005, Plus Pairings, Martian Meteorite From Al Wusta, Oman, Arshad Ali, Sobhi Nasir, Iffat Jabeen, Ahmed Al-Rawas Apr 2025

Review Of The Sayh Al Uhaymir (Sau) 005, Plus Pairings, Martian Meteorite From Al Wusta, Oman, Arshad Ali, Sobhi Nasir, Iffat Jabeen, Ahmed Al-Rawas

Sultan Qaboos University Journal For Science

Al Wusta is a desert area in the Sultanate of Oman which is famous due to the discovery of a number of Martian and Lunar meteorites since the start of the present millennium. According to the Meteoritical Bulletin database, 137 approved Martian meteorites have been found worldwide, including 17 from Oman (4 from Zufar, 13 from Al Wusta region). Interestingly 11 finds in the last 15 years have been of Sayh al Uhaymir (SaU) 005 and its pairings. These finds (estimated mass = 11.2 kg) are linked to 10 search expeditions carried out between November 26, 1999 and March 2, …

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Combined Effects Of Hall Current And Heat Transfer On Peristaltic Transport Of A Nanofluid In A Vertical Tapered Channel Through A Porous Medium, Ahmed I. Abdellateef, Syed Z. Ul Haque Apr 2025

Combined Effects Of Hall Current And Heat Transfer On Peristaltic Transport Of A Nanofluid In A Vertical Tapered Channel Through A Porous Medium, Ahmed I. Abdellateef, Syed Z. Ul Haque

Sultan Qaboos University Journal For Science

The influences of Hall currents and heat transfer on peristaltic transport of a nanofluid in a vertical porous tapered channel through a porous medium are investigated theoretically and graphically under the assumptions of low Reynolds number and long wavelength and the flow investigated is in a wavy frame of reference. Analytical solutions are obtained for temperature, axial velocity, stream function and pressure gradient. Graphical results are sketched for various embedded parameters.

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An Improved Mnemonic Device For Thermodynamic Relations, Younghun Kim, Rengaraj Selvaraj Apr 2025

An Improved Mnemonic Device For Thermodynamic Relations, Younghun Kim, Rengaraj Selvaraj

Sultan Qaboos University Journal For Science

An improved mnemonic device for thermodynamic relations between state variables and potentials was proposed in the form of a thermodynamic circle. Based on separating the Born square into an inner square (T, P, V, and S) and an outer circle (G, A, U, and H), relations such as Legendre transforms, Maxwell equations, equations to compute variables, and differential equations for thermodynamic variables can be recalled easily. The thermodynamic circle has a cross-arrow at its center and can be used to intuitively determine the sign of all thermodynamic relations.

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4d Pyritohedral Symmetry, Nazife O. Koca, Amal J.H. Al Qanobi, Mehmet Koca Apr 2025

4d Pyritohedral Symmetry, Nazife O. Koca, Amal J.H. Al Qanobi, Mehmet Koca

Sultan Qaboos University Journal For Science

We describe an extension of the pyritohedral symmetry in 3D to 4-dimensional Euclidean space and construct the group elements of the 4D pyritohedral group of order 576 in terms of quaternions. It turns out that it is a maximal subgroup of both the rank-4 Coxeter groups W (F4) and W (H4), implying that it is a group relevant to the crystallographic as well as quasicrystallographic structures in 4-dimensions. We derive the vertices of the 24 pseudoicosahedra, 24 tetrahedra and the 96 triangular pyramids forming the facets of the pseudo snub 24-cell. It turns out that the relevant lattice is the …

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Effects Of Second-Order Slip And Viscous Dissipation On The Analysis Of The Boundary Layer Flow And Heat Transfer Characteristics Of A Casson Fluid, Mohammad M. Rahman, Ioan Pop Apr 2025

Effects Of Second-Order Slip And Viscous Dissipation On The Analysis Of The Boundary Layer Flow And Heat Transfer Characteristics Of A Casson Fluid, Mohammad M. Rahman, Ioan Pop

Sultan Qaboos University Journal For Science

The aim of the present study is to analyze numerically the steady boundary layer flow and heat transfer characteristics of Casson fluid with variable temperature and viscous dissipation past a permeable shrinking sheet with second order slip velocity. Using appropriate similarity transformations, the basic nonlinear partial differential equations have been transformed into ordinary differential equations. These equations have been solved numerically for different values of the governing parameters namely: shrinking parametersuction parameterCasson parameterfirst order slip parametersecond order slip parameter Prandtl number and the Eckert number using the bvp4c function from MATLAB. A stability analysis has also been performed. Numerical results …

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Geological Assessment Of The Khor Kharfot Sediments, Western Dhofar Region, Sultanate Of Oman, Iftikhar A. Abbasi Apr 2025

Geological Assessment Of The Khor Kharfot Sediments, Western Dhofar Region, Sultanate Of Oman, Iftikhar A. Abbasi

Sultan Qaboos University Journal For Science

Khor Kharfot is part of a coastal estuarine wetland system located in the western part of the Dhofar Governorate preserving a pristine ecosystem supporting a distinct vegetation and animal habitat. A sand barrier along the khor (local term for wetlands) mouth controls the mixing of fresh and marine water in the enclosed lagoon. In order to understand the geological controls on the khor formation, a geological map of the khor barrier and inlet area is prepared. The khor is bounded by Cretaceous and Tertiary carbonate rock sequences which are cut by a number of faults. The khor mouth and barrier …

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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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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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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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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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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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