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Lithology Characteristics And Diagenesis Of Late Pleistocene-Holocene Coastal Terraces Of The Yemeni Red Sea: Implication For Paleoclimatic Records, Ahmed Saif Al-Mikhlafi Apr 2025

Lithology Characteristics And Diagenesis Of Late Pleistocene-Holocene Coastal Terraces Of The Yemeni Red Sea: Implication For Paleoclimatic Records, Ahmed Saif Al-Mikhlafi

Sultan Qaboos University Journal For Science

The development of Holocene-Pleistocene fringing reefs in the Yemeni Red Sea (YRS) is controlled by sediment input and variations in accommodation space. Lithostratigraphic correlation of environmental facies in the investigated sites shows a sequence of successive events, and each can be subdivided into 2 or 3 main sequences. The upper sequence is characterized by the dominance of coral and coralline algal frameworks. The lower sequences are varied and can be attributed to spatial and temporal variability. Meteoric diagenesis is the most dominant and includes dissolution, calcrete, and coral recrystallization. Lithologic and mineralogic investigations of the Pleistocene-Holocene coral reefs display three …

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A Surface Network Based On Polytyramine/ Gold Nanoparticles: Characterization, Kinetics, Thermodynamics And Selective Determination Of Norepinephrine, Emad A. Khudaish, Arwa Al-Maskari Apr 2025

A Surface Network Based On Polytyramine/ Gold Nanoparticles: Characterization, Kinetics, Thermodynamics And Selective Determination Of Norepinephrine, Emad A. Khudaish, Arwa Al-Maskari

Sultan Qaboos University Journal For Science

A solid-state sensor was fabricated by a spontaneous electrochemical deposition of polytyramine (Ptyr) film onto a glassy carbon electrode (GCE) which was further peripherally supported by gold nanoparticles (AuNPs). The surface materials of the developed sensor (AuNPs.Ptyr-GCE) were characterized by X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The rate constant of charge transfers (kct) of the as-prepared sensor (8.77 × 10-4 cm/s) was evaluated by fitting the charge transfer resistance (Rct) data in the presence of ferric-ferrous hexacyanide redox couple solution, [Fe(CN)6]3-/4-. The voltammetric behavior of norepinephrine (NOR) was confirmed to …

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Parasitic Contamination Of Local Drinking Water Sources In Aba Metropolis, Abia State, Nigeria, Blessing U. Ejike, Carmelita C. Ohaeri, Ebube C. Amaechi Apr 2025

Parasitic Contamination Of Local Drinking Water Sources In Aba Metropolis, Abia State, Nigeria, Blessing U. Ejike, Carmelita C. Ohaeri, Ebube C. Amaechi

Sultan Qaboos University Journal For Science

Water-borne parasitic infections have become a source of concern in recent times due to the contamination of various water sources. A survey on the parasitic contamination of local drinking water sources in Aba metropolis was carried out between August and October 2018. This was done to evaluate the extent of contamination of these water sources and their public health implications. A total number of eighty (80) water samples were investigated from five (5) major water sources within the study area using the standard sedimentation method and examined for parasite cysts, eggs and larvae. Physical/macroscopic examination was done to determine the …

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Travelling Wave Solutions For Fisher’S Equation Using The Extended Homogeneous Balance Method, Mohammad M. Fares, Usama M. Abdelsalam, Faiza M. Allehiany Apr 2025

Travelling Wave Solutions For Fisher’S Equation Using The Extended Homogeneous Balance Method, Mohammad M. Fares, Usama M. Abdelsalam, Faiza M. Allehiany

Sultan Qaboos University Journal For Science

In this work, the extended homogeneous balance method is used to derive exact solutions of nonlinear evolution equations. With the aid of symbolic computation, many new exact travelling wave solutions have been obtained for Fisher’s equation and Burgers-Fisher equation. Fisher’s equation has been widely used in studying the population for various systems, especially in biology, while Burgers-Fisher equation has many physical applications such as in gas dynamics and fluid mechanics. The method used can be applied to obtain multiple travelling wave solutions for nonlinear partial differential equations.

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Predator-Prey Model With Refuge, Fear And Z-Control, Ibrahim M. Elmojtaba, Kawkab Al-Amri, Qamar J.A. Khan Apr 2025

Predator-Prey Model With Refuge, Fear And Z-Control, Ibrahim M. Elmojtaba, Kawkab Al-Amri, Qamar J.A. Khan

Sultan Qaboos University Journal For Science

In this paper, we consider a predator-prey model incorporating fear and refuge. Our results show that the predator-free equilibrium is globally asymptotically stable if the ratio between the death rate of predators and the conversion rate of prey into predator is greater than the value of prey in refuge at equilibrium. We also show that the co-existence equilibrium points are locally asymptotically stable if the value of the prey outside refuge is greater than half of the carrying capacity. Numerical simulations show that when the intensity of fear increases, the fraction of the prey inside refuge increases; however, it has …

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Comparing Science And Engineering Students Using The Force Concept Inventory In Introductory Physics Courses, Nazife Koca, Nidhal Sulaiman Apr 2025

Comparing Science And Engineering Students Using The Force Concept Inventory In Introductory Physics Courses, Nazife Koca, Nidhal Sulaiman

Sultan Qaboos University Journal For Science

This work is intended to analyze and compare the performance of two groups of students on the understanding of force and motion concepts using the Force Concept Inventory (FCI). The FCI test serves questions on basic Newtonian concepts where the answers inclyde the correct response and commonly misconceived alternatives. The FCI test was implemented twice as pre and post-tests for two introductory calculus-based physics courses offered at the Sultan Qaboos University (SQU) in Oman for students mainly from the Colleges of Sciences, Education and Agriculture and the students from the College of Enginerring in the Spring 2017 and Spring 2018 …

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Determination Of Toxic Metals In Tobacco From Selected Imported Cigarette Brands And Local Tobacco In Iraqi Markets, Wedad H. Al-Dahhan, Emad Yousif, Hassan Hashim Apr 2025

Determination Of Toxic Metals In Tobacco From Selected Imported Cigarette Brands And Local Tobacco In Iraqi Markets, Wedad H. Al-Dahhan, Emad Yousif, Hassan Hashim

Sultan Qaboos University Journal For Science

Metals are essential in many physiological processes in the human body, but can also be detrimental to our health when the concentration is not within recommended permissible limits. Various types of cigarettes were selected from the local markets in Iraq in addition to the Iraqi tobacco from Sulaymaniyah governorate to conduct tests of the elements in these species. The selected samples were tested using EDX instrument. Results proved the presence of dangerous elements such as Cr, Ni, Zn, As, Al, P, S, Pb, Cd, Sn and Sb in quantities which could greatly affect the health of the smoker and have …

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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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Effect Of Smokeless Tobacco Product, Afzal, On The Reproductive Hormones And Gonadal Pathology Of Wistar Rats, Nawal Al-Mukhaini, Taher Ba Omar, Elsadig Eltayeb, Aisha Al Khayat Al-Shehi, Jamila Al-Belushi, Nafila Al-Riyami, Romulo Cipriano, Kawther Al-Adawi Apr 2025

Effect Of Smokeless Tobacco Product, Afzal, On The Reproductive Hormones And Gonadal Pathology Of Wistar Rats, Nawal Al-Mukhaini, Taher Ba Omar, Elsadig Eltayeb, Aisha Al Khayat Al-Shehi, Jamila Al-Belushi, Nafila Al-Riyami, Romulo Cipriano, Kawther Al-Adawi

Sultan Qaboos University Journal For Science

Afzal is a common smokeless tobacco product (STP) in Oman, and it is believed to contain toxins that may affect the reproductive hormones and hence reproductive function. This study assessed the effect of Afzal on the gonads of Wistar rats. In order to assess gonad toxicity induced by this STP, an aqueous extract of Afzal was added to drinking water to be administrated orally to Wistar albino rats (n = 72) classified as young (4 weeks old) and adult (20 weeks old) of both genders weighing between 60-80 g and 150-240 g respectively for 8 weeks. The rats were divided …

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Nutrient Content, In Vitro Ruminal Fermentation Characteristics And Antimethanogenic Potential Of Three Algerian Asteraceae Species, Serine Amokrane, Rabah Arhab, Serina Calabro, Raffaella Tudisco, Federico Infascelli, Moufida Aggoun Apr 2025

Nutrient Content, In Vitro Ruminal Fermentation Characteristics And Antimethanogenic Potential Of Three Algerian Asteraceae Species, Serine Amokrane, Rabah Arhab, Serina Calabro, Raffaella Tudisco, Federico Infascelli, Moufida Aggoun

Sultan Qaboos University Journal For Science

The in vitro rumen fermentation parameters and the antimethanogenic potential of three Asteraceae species: Chamaemelum nobile, Centaurea pulata and Chrysanthemum segetum were determined. Serum bottles containing 200 mg of each plant and 30 ml of the culture medium (artificial saliva plus rumen juice) were incubated for 24 h. After incubation, pH, volatile fatty acid (VFA), ammonia (NH3) and methane (CH4) productions were recorded. Methanogens and protozoa were quantified using a Real Time PCR technique (qPCR). Cumulative gas productions, in vitro organic matter digestibility and VFA were not significantly affected by the added species when compared to the control (P > 0.05). …

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Distribution Of Nutrient Salts And Chlorophyll-A In Surface Water Along The Gulf Of Aden And Arabian Sea Coast, Yemen, Ibrahim A. Al-Akhaly, Nabil A. Al-Shwafi, Shehab A. Al-Kabsh Apr 2025

Distribution Of Nutrient Salts And Chlorophyll-A In Surface Water Along The Gulf Of Aden And Arabian Sea Coast, Yemen, Ibrahim A. Al-Akhaly, Nabil A. Al-Shwafi, Shehab A. Al-Kabsh

Sultan Qaboos University Journal For Science

The distribution of inorganic nutrient salts (ammonium, nitrite, nitrate, phosphate and silicate) and phytoplankton chlorophyll-a (Chl-a) were investigated in the Gulf of Aden and along the Arabian Sea coast, Yemen. Seventy two surface water samples were collected during cruises in August 2014 and January 2015. The sampled area extends from As Suqayyah in the west of the Gulf of Aden to Hawf in the east. The study showed that the average values of nutrient salts (μg/l) in waters collected in August 2014 and January 2015 were 0.83 and 0.60, 10.98 and 10.03, 16.41 and 14.73, 10.36 and 8.76, and 29.72 …

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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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Synthesis Of Pullulan-Mediated Silver Nanoparticles (Agnps) And Their Antimicrobial Activities, Yusra Al-Owasi, Abdulkhadir Elshafie, Nallusamy Sivakumar, Saif Al-Bahry Apr 2025

Synthesis Of Pullulan-Mediated Silver Nanoparticles (Agnps) And Their Antimicrobial Activities, Yusra Al-Owasi, Abdulkhadir Elshafie, Nallusamy Sivakumar, Saif Al-Bahry

Sultan Qaboos University Journal For Science

The synthesis of silver nanoparticles (AgNPs), using plant extracts, bacteria, fungi and yeasts, and their antimicrobial activities have been widely investigated and well documented. However, pullulan AgNPs and their antimicrobial activities have not received much attention. The objective of this study was to synthesize pullulan AgNPs, characterize them, and test their antibacterial and antifungal activities. Pullulan was extracted from Aureobasidium mangrovei isolated from Oman and, using UV-Vis spectroscopy and Fourier Transform Infrared (FT-IR), found to be identical to the commercial pullulan obtained from Sigma, USA. Transmission electron microscopy (TEM) showed that most of the synthesized particles were poly-dispersed, irregular in …

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Molecular Characterization Of Fumonisin Mycotoxin Genes Of Fusarium Sp Isolated From Corn And Rice Grains, Latifa Al-Husnan, Muneera Al-Kahtani, Randa Farag Apr 2025

Molecular Characterization Of Fumonisin Mycotoxin Genes Of Fusarium Sp Isolated From Corn And Rice Grains, Latifa Al-Husnan, Muneera Al-Kahtani, Randa Farag

Sultan Qaboos University Journal For Science

Fungi mycotoxins can be a serious risk to health and lead to substantial economic loss. The environmental conditions of Saudi Arabia, with its mostly warm temperatures, are conducive to the growth of toxigenic fungi resulting in mycotoxin production in different food items. The current study elucidates the natural occurrence of toxigenic fungi and mycotoxin production in grains in Saudi Arabia. Samples of white rice and corn (yellow, red) grains were collected from different local markets and houses. Three fungal isolates were obtained from the corn and rice grains and examined using Potato Dextrose Agar (PDA) and Carnation Leaf Agar (CLA) …

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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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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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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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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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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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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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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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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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Composition Of Solid Waste In Al Jabal Al Akhdar, A Mountain Region Undergoing Rapid Urbanization In Northern Oman, Abdullah I. Al-Mahrouqi, Reginald Victor Apr 2025

Composition Of Solid Waste In Al Jabal Al Akhdar, A Mountain Region Undergoing Rapid Urbanization In Northern Oman, Abdullah I. Al-Mahrouqi, Reginald Victor

Sultan Qaboos University Journal For Science

There is a lack of data on the generation and composition of waste in rural areas worldwide. The present study analyzed the composition of solid waste in Al Jabal Al Akhdar, a rural mountain region in the Sultanate of Oman, which is presently experiencing a rapid rate of urbanization due to tourism development. The solid wastes here are generated by the municipality collecting waste from residential, commercial, institutional and recreational areas, the military from a training camp and a few non-governmental private companies from their camps and hotels. The whole load from each of the three sources was manually segregated …

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Morphometry Of Organs In Sheep Fed A Diet Containing Tannins And Polyphenols, Osman Mahgoub, Ibrahim Inwa, Isam T. Kadim, Mohamed H. Tageldin, Kaadhia Al-Kharousi Apr 2025

Morphometry Of Organs In Sheep Fed A Diet Containing Tannins And Polyphenols, Osman Mahgoub, Ibrahim Inwa, Isam T. Kadim, Mohamed H. Tageldin, Kaadhia Al-Kharousi

Sultan Qaboos University Journal For Science

The aim of this study was to use morphometry to investigate the essential organs of sheep fed with non-conventional diets. Twelve male Omani sheep were fed with one of two types of roughages supplemented with a commercial concentrate for 63 days and then slaughtered. The volumes of their kidneys, testes, and livers were measured. Random samples from the organs were fixed in formalin and embedded in paraffin. Random five micrometer sections from each block were stained with hematoxylin and eosin. Images from four random fields were taken from each slide using a digital camera attached to the microscope and then …

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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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Effect Of Nano Sb2o3 On The Dispersive Optical Constants Of Pmma Films, Wasan A. Al-Taa'y, Mohammed T. Abdul Nabi, Saad F. Oboudi, Emad Yousif Apr 2025

Effect Of Nano Sb2o3 On The Dispersive Optical Constants Of Pmma Films, Wasan A. Al-Taa'y, Mohammed T. Abdul Nabi, Saad F. Oboudi, Emad Yousif

Sultan Qaboos University Journal For Science

Pure and Antimony Trioxide Sb2O3 doped PMMA films were prepared by the casting method. Optical absorption measurements in the wavelength range 200-800 nm were studied by using a computerized UV-Vis spectrophotometer (Shimadzu UV-1601 PC) and these confirmed that PMMA films have a direct band gap that decreases from 5.15 to 4.66 eV as the doping concentration increases to 5wt%. The increase in the density of localized states from 8.9 to 74.5 meV causes an expansion in the Urbach tail and consequently decreases the energy gap. The dispersion of the refractive index was analyzed using the concept of a single oscillator. …

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Computational Study Of Geometry, Solvation Free Energy, Dipole Moment, Polarizability, Hyperpolarizability And Molecular Properties Of 2-Methylimidazole, Mohammad Firoz Khan, Ridwan Bin Rashid, Shahidul M. Islam, Mohammad A. Rashid Apr 2025

Computational Study Of Geometry, Solvation Free Energy, Dipole Moment, Polarizability, Hyperpolarizability And Molecular Properties Of 2-Methylimidazole, Mohammad Firoz Khan, Ridwan Bin Rashid, Shahidul M. Islam, Mohammad A. Rashid

Sultan Qaboos University Journal For Science

Ab initio calculations were carried out to study the geometry, solvation free energy, dipole moment, molecular electrostatic potential (MESP), Mulliken and Natural charge distribution, polarizability, hyperpolarizability, Natural Bond Orbital (NBO) energetic and different molecular properties like global reactivity descriptors (chemical hardness, softness, chemical potential, electronegativity, electrophilicity index) of 2-methylimidazole. B3LYP/6-31G(d,p) level of theory was used to optimize the structure both in the gas phase and in solution. The solvation free energy, dipole moment and molecular properties were calculated by applying the Solvation Model on Density (SMD) in four solvent systems, namely water, dimethylsulfoxide (DMSO), n-octanol and chloroform. The computed bond …

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