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Articles 1 - 25 of 25
Full-Text Articles in Physical Sciences and Mathematics
Study Of Radon Concentrations In Some Of Public Ground Water Wells, Sana'a - Yemen, Ahmed Khalid Abdul-Rahim, Najwa Ahmed Al-Maqtari
Study Of Radon Concentrations In Some Of Public Ground Water Wells, Sana'a - Yemen, Ahmed Khalid Abdul-Rahim, Najwa Ahmed Al-Maqtari
Hadhramout University Journal of Natural & Applied Sciences
This study aims to assess radon-222 concentration levels in public ground water wells in Sana'a city, Yemen. Forty-three well water samples were collected from the study area. The alpha spectroscopy method was used to measure the samples using a RAD7 detector. The radon concentrations were in the range from 0.82 ± 0.38 Bq/L to 38.73 ± 2.98 Bq/L. A moderate correlation of radon levels with aquifer type was observed. Also, weak correlations of radon levels with electric conductivity, pH, and temperature, and no correlation with measured heavy metals were observed. Annual effective dose rates () were calculated and were found …
Synthesis And Characterization Of New Azo Dyes Derived From Acyclovir And Sulfamethoxazole And Study Their Biological Activity, Abdul Rahman Y. Wahoud, Thanaa Shriteh, Ali Yousef, Mohammad Mazen Kondakji
Synthesis And Characterization Of New Azo Dyes Derived From Acyclovir And Sulfamethoxazole And Study Their Biological Activity, Abdul Rahman Y. Wahoud, Thanaa Shriteh, Ali Yousef, Mohammad Mazen Kondakji
Hadhramout University Journal of Natural & Applied Sciences
In this research, two new azo dyes, 9-(2-Hydroxy-ethoxymethyl)-2-(2-hydroxy5nitrophenylazo)-1,9-dihydro-purin-6-one and 4-(2-Hydroxy-napHthalen-1-ylazo)-N-(5-methyl-isoxazol-3-yl)-benzenesulfonamide, derived from Acyclovir and Sulfamethoxazole was synthesized. The first dye synthesis was started by diazation of acyclovir, then combined with 4-nitrophenol activated with potassium hydroxide 10%, yielding 80%, and its purity was verified by thin layer chromatography (TLC). The second dye synthesis was started by diazation of Sulfamethoxazole then combined with β-naphthol activated with potassium hydroxide 10%, yielding 87%, and its purity was verified by thin layer chromatography (TLC). The identity of the resulting pigments was determined based on spectroscopic methods such as infrared spectroscopy, proton nuclear magnetic resonance spectrum …
Improved Operational Matrices Of Dp-Ball Polynomials For Solving Singular Second Order Linear Dirichlet-Type Boundary Value Problems, Ahmed Kherd, Salim F. Bamsaoud, Omar Bazighifan, Mobarek A. Assabaai
Improved Operational Matrices Of Dp-Ball Polynomials For Solving Singular Second Order Linear Dirichlet-Type Boundary Value Problems, Ahmed Kherd, Salim F. Bamsaoud, Omar Bazighifan, Mobarek A. Assabaai
Hadhramout University Journal of Natural & Applied Sciences
Solving Dirichlet-type boundary value problems (BVPs) using a novel numerical approach is presented in this study. The operational matrices of DP-Ball Polynomials are used to solve the linear second-order BVPs. The modification of the operational matrix eliminates the BVP's singularity. Consequently, guaranteeing a solution is reached. In this article, three different examples were taken into consideration in order to demonstrate the applicability of the method. Based on the findings, it seems that the methodology may be used effectively to provide accurate solutions.
On The Stability Of First Order Ordinary Differential Equation With A Nonlocal Condition, Ebtisam Omer Bin-Taher
On The Stability Of First Order Ordinary Differential Equation With A Nonlocal Condition, Ebtisam Omer Bin-Taher
Hadhramout University Journal of Natural & Applied Sciences
In this paper we study the existence and uniqueness of solution for the first order differential equation,𝑑𝑥𝑑𝑡 + 𝑓(𝑡,𝑥(𝑡))=0,𝑡∈[0,𝑇] with the nonlocal condition 𝑥(1)+ 𝐼𝛾 𝑥(𝑡)|𝑡=𝑡𝑜=𝑥𝑜 ., then we prove that the solution is uniformly stable
The Generalized Q-Analogue Hermite Matrix Polynomials Of Two Variables, Fadhl Saleh Nasser Alsarahi
The Generalized Q-Analogue Hermite Matrix Polynomials Of Two Variables, Fadhl Saleh Nasser Alsarahi
Hadhramout University Journal of Natural & Applied Sciences
In this paper, we introduce the q-analogue generalized Hermite matrix polynomials of two variables. Some recurrence relations for these q-polynomials are derived.
Seventh And Twelfth-Order Iterative Methods For Roots Of Nonlinear Equations, Hassan Mohamed Bawazir
Seventh And Twelfth-Order Iterative Methods For Roots Of Nonlinear Equations, Hassan Mohamed Bawazir
Hadhramout University Journal of Natural & Applied Sciences
This study presents two iterative methods, based on Newton’s method, to attain the numerical solutions of nonlinear equations. We prove that our methods have seven and twelve orders of convergence. The analytical investigation has been established to show that our schemes have higher efficiency indexes than some recent methods. Numerical examples are executed to investigate the performance of the proposed schemes. Moreover, the theoretical order of convergence is verified on the numerical examples.
Q-Analogue Modified Laguerre And Generalized Laguerre Polynomials Of Two Variables, Fadhle Bin Fadhle Mohsen, Fadhl Saleh .Alsarahi
Q-Analogue Modified Laguerre And Generalized Laguerre Polynomials Of Two Variables, Fadhle Bin Fadhle Mohsen, Fadhl Saleh .Alsarahi
Hadhramout University Journal of Natural & Applied Sciences
The 𝑞-Laguerre polynomials are important 𝑞-orthogonal polynomials whose applications and generalizations arise in many applications such as quantumgroup (oscillator algebra, etc.), 𝑞-harmonic oscillator and coding theory. In this paper, we introduce the q-analogue modified Laguerre and generalized modified Laguerre polynomials of two variables . Some recurrence relations for these polynomials are derived.
A Numeric Study On The Influence Of The Values Of The Parameter P In Kronig – Peneny Equation On The Width Of The Bands, Saleh Saeed Barbaid
A Numeric Study On The Influence Of The Values Of The Parameter P In Kronig – Peneny Equation On The Width Of The Bands, Saleh Saeed Barbaid
Hadhramout University Journal of Natural & Applied Sciences
After showing the importance of Bloch Theory about Schrödinger' equation solution with a periodic potential; we demonstrated that the periodic structure of square well in one dimension of the model of Kronig-Penney on the band theory of solid, shows clearly the structure of the allowed and forbidden bands in the crystallized solids and we showed how we can introduce the parameter p in the final equation of this model of bands. Then, we conducted a sufficient study on the influence of this parameter on the widths of the allowed and forbidden energy bands in the crystals. We find that the …
Thermodynamic And Kinetic Of Eriochrome Black-T Adsorption Onto Yemeni Palm-Date Stones, Abdulrahman Yousef Wahoud, Sawsan Awadh Almaqdi
Thermodynamic And Kinetic Of Eriochrome Black-T Adsorption Onto Yemeni Palm-Date Stones, Abdulrahman Yousef Wahoud, Sawsan Awadh Almaqdi
Hadhramout University Journal of Natural & Applied Sciences
Removal of eriochrome black-T (EB-T) dye from aqueous solutions was performed by adsorption onto Yemeni palmdate stones. The adsorption isotherm was found to follow the Langmuir model. Two simplified kinetic models including pseudo-first order and pseudo-second order equation were selected to follow the adsorption processes. Kinetic studies showed that the adsorption followed pseudo-first order kinetic model. Various thermodynamic parameters such as Δ𝐻 = -3465.3 J/mole and Δ𝑆 = -10.1 J/K/mole. Δ𝐺 was found to be -4495.5, -2195.2, -2235.7 and -45.39 J/mole at 298, 318, 328 and 338 K respectively, the maximum adsorption capacity was equal to 142 mg/g. The results …
Effect Of Calcium Carbonate, Ph, Mud And Organic Carbon On Soil Phosphate Sedimentation For Some Farms In Wadi Hadramout, Abdul Aziz Salem Dayan
Effect Of Calcium Carbonate, Ph, Mud And Organic Carbon On Soil Phosphate Sedimentation For Some Farms In Wadi Hadramout, Abdul Aziz Salem Dayan
Hadhramout University Journal of Natural & Applied Sciences
This study was conducted to determine the effect of calcium carbonate, pH, the amount of clay on phosphate adsorption, and the effect of early fertilization of phosphatic fertilizer on the amount of fertilizer. Three samples of surface soil (0-30 cm) were obtained from Al-Mashhad (Cotton) and (Sweiri) farms, Hadramout governorate, which differ in their content for: Total calcium carbonate ratio. The amount of clay in its mechanical analysis. Organic carbon.pH (pH).The samples were incubated at room temperature (24-28° C) and at varying concentrations of Monocalsumphosphate. The correlation coefficient was used to find the statistical relationship between the adsorption and release …
Pd Doped Sno2 Resistive Film As A Non-Enzymatic Glucose Sensor, Salim F. Bamsaoud, Sandhya Rani, R. N. Karekar Prof., S. W. Gosavi
Pd Doped Sno2 Resistive Film As A Non-Enzymatic Glucose Sensor, Salim F. Bamsaoud, Sandhya Rani, R. N. Karekar Prof., S. W. Gosavi
Hadhramout University Journal of Natural & Applied Sciences
A new sugar sensor based on metal oxide is presented here. The variation on the sensor resistance is studied against different glucose and fructose concentrations (1 - 360 mg/dl). The study is done for three different resistive films (i) pristine palladium oxide (PdOx); (ii) tin oxide (SnO2) and (iii) palladium doped tin oxide (Pd-SnO2). The chemical reactions of glucose and fructose with surface species were studied. Pd-SnO2 films show an excellent and reliable response to glucose and fructose solution in comparison with the bare films (PdOx and SnO2). Sensor performance was checked for the blood of normal (120 mg/d) and …
A Chebyshev Spectral Collocation Method For Solving Kdv-Burgers Equation, Mubarak Awadh Assabaai
A Chebyshev Spectral Collocation Method For Solving Kdv-Burgers Equation, Mubarak Awadh Assabaai
Hadhramout University Journal of Natural & Applied Sciences
A mixed spectral/ Runge-Kutta method is used to obtain numerical solutions of Kortewege–de Vries–Burgers’ (KdVB) equation. The suggested method based on Chebyshev spectral collocation is used with Runge-Kutta method of order four. This technique is accomplished by starting with a Chebyshev approximation for the higher order derivatives in the x -direction and generating approximations to the lower derivatives through successive integrations of the highest-order derivative. The proposed technique reduces the problem to a system of ordinary differential equations in the t -direction. The Runge-Kutta method of order four is used to solve this system. Excellent numerical results have been obtained …
Some Optical Properties Of (Znte) Thin Films Prepared By Thermal Evaporation Technique On A Glass Substrate, Abdulla Saeed Ba-Sabiah, Mohamed Ali Seyam
Some Optical Properties Of (Znte) Thin Films Prepared By Thermal Evaporation Technique On A Glass Substrate, Abdulla Saeed Ba-Sabiah, Mohamed Ali Seyam
Hadhramout University Journal of Natural & Applied Sciences
Thin films of Zinc telluride (ZnTe)were deposited by thermal evaporation technique on a glass substrate. The optical obtained data were analyzed using a numerical analysis program which showed that the transition mechanism involved indirectly allows transition since the best line dependence is obtained from a plot of 0.5 ( ) h versus photon energy ( ) h . The bandgap decreased from 1.15 to 0.96 eV as the substrate temperature varied from 410 to 510 K. Such behaviour is attributed to unsaturated defects, which are confirmed by XRD examinations. PACS:78.20.Ci, 71.30.+h, 72.90. +y
Assessment Of Heavy Metal Pollution In The Seawater Of Hadhramout Coastal Area, Yemen, Nabil Abdo Al-Shwaf, Mohammed Abdulla Al-Wosabi, Hisham Mohammed Nagi, Nada Sheikh Mol-Aldwila
Assessment Of Heavy Metal Pollution In The Seawater Of Hadhramout Coastal Area, Yemen, Nabil Abdo Al-Shwaf, Mohammed Abdulla Al-Wosabi, Hisham Mohammed Nagi, Nada Sheikh Mol-Aldwila
Hadhramout University Journal of Natural & Applied Sciences
Hadhramout is considered as the industrial and commercial center for fishing in Yemen. Accordingly, Yemen food security depends highly on maritime products of Hadhramout. Consequently, any severe contamination caused by industrial activities would have direct or indirect negative impact on the sea life and marine environment. Seawater samples were collected from Hadhramout Governorate coastal area Yemen. Five sampling locations were selected to conduct the present study. The samples were taken on a seasonal basis from Augusts of 2013 until May 2014. Twenty seawater samples were collected from the five areas (Ras sharma, Burum, AL-Mukalla, AL-Sheher and Arryidah) at Hadhramout coastal …
The Effect Of Climate Change On The Water Reserve In Wadi Of Hadhramout, Jamal A. Abbad, Khaled S. Bawahidi, Mohamed A. Bawadi
The Effect Of Climate Change On The Water Reserve In Wadi Of Hadhramout, Jamal A. Abbad, Khaled S. Bawahidi, Mohamed A. Bawadi
Hadhramout University Journal of Natural & Applied Sciences
This research aims to study the reality of the impact of climate change on water resources in Wadi (valley) of Hadhramout, as this region is exposed to the impacts of climate change on groundwater resources, through the effects on rainfall and surface water supplies. Climate change is a global phenomenon affecting water resources, so it is necessary to study its impact, specifically on the water reserve in wadi of Hadhramout. from this point of view this problem was taken into account in our study in terms of the possibility of maintaining the balance of water reserves in the study area. …
Proving The Possibility Of The Calculation Of The Madeluag Constant For The Sodium Chloride Crystal Using A Limited Number Of The Terms Of The Series Giving The Expression Of This Constant, Saleh Saeed Barbaid
Proving The Possibility Of The Calculation Of The Madeluag Constant For The Sodium Chloride Crystal Using A Limited Number Of The Terms Of The Series Giving The Expression Of This Constant, Saleh Saeed Barbaid
Hadhramout University Journal of Natural & Applied Sciences
In this research, after referring to the basic assumption of the theory of the binding energy of the ionic crystals, we explained the Madelung constant and then, we show how the method of the neutral electric groups introduced by Evjen facilitates the convergent of the series showing the Madelung constant. Then, afterwards, we reviewed the principal points of the crystalline structure of the sodium chloride which crystallizes in a cubic faces centred lattice; showing that the apparition 0f 27 ions in each unit cell of its space lattice; afterward we calculate different values of the Madelung constant, showing how we …
Investigating Thermodynamics And Kinetics Of Methylene Blue And Eriochrome Black-T Adsorption On Activated Carbon Prepared From Coconut Husk, Abdul Rahman Wahoud, Lotfi Abdul Samed Bawazer
Investigating Thermodynamics And Kinetics Of Methylene Blue And Eriochrome Black-T Adsorption On Activated Carbon Prepared From Coconut Husk, Abdul Rahman Wahoud, Lotfi Abdul Samed Bawazer
Hadhramout University Journal of Natural & Applied Sciences
In this research, the adsorption process was studied for methylene blue eriochrome black-T from aqueous solutions on the surface of activated carbon prepared from coconut husk by chemical activation with potassium hydroxide. The results show that the adsorption isotherm for methylene blue follows the Langmuir model while it follows the Freundlich model and the maximum adsorption capacity was 909 mg/g for methylene blue and 262 mg/g for eriochrome black-T. The equilibrium contact time reached in about 90 minutes at lower concentrations and 120 minutes at higher concentrations. Two simplified kinetic models including pseudo-first-order and pseudo-second-order equations were selected to follow …
Fifth And Eleventh-Order Iterative Methods For Roots Of Nonlinear Equations, Hassan Mohammed Bawazir
Fifth And Eleventh-Order Iterative Methods For Roots Of Nonlinear Equations, Hassan Mohammed Bawazir
Hadhramout University Journal of Natural & Applied Sciences
In this work, two iterative methods, based on Newton’s method, to obtain the numerical solutions of nonlinear equations have been constructed. We proved that our methods converge in fifth and eleventh orders. Analytical investigation has been established to show that our schemes have higher efficiency indexes than some recent methods. Numerical examples are experimented to investigate the performance of the proposed schemes. Moreover, the theoretical order of convergence is verified in the experiment work.
On N Satisfying, N Dividing Φ(N)Σ(N)+1, Hussain Abdulkader Al-Aidroos
On N Satisfying, N Dividing Φ(N)Σ(N)+1, Hussain Abdulkader Al-Aidroos
Hadhramout University Journal of Natural & Applied Sciences
Let denotes the sum of the positive divisors of the positive integer and be the Euler’s totient function([1],page25). Cleary, divides if is a prime. Then, the question is there a composite that divides ? Considering this problem Yang-Gao Chen and Jin-Hui Fang [5] have proved that , where as usual is the number of distinct prime factors of. and , .We devoted the study of this problem where we prove that every in is odd and that , from which it follows that for any composite in the least prime factors is . Also, we obtained lower bounds for and …
Assessment Of Temperature Change In Mukalla City In Hadhramaut Governorate And Its Impact On The Environment, Jamal Abu Bakr Abbad, Fahad Hussein Alsomahi, Nabeela Obeid Baharah, Fatima Saleh Alsaeedi
Assessment Of Temperature Change In Mukalla City In Hadhramaut Governorate And Its Impact On The Environment, Jamal Abu Bakr Abbad, Fahad Hussein Alsomahi, Nabeela Obeid Baharah, Fatima Saleh Alsaeedi
Hadhramout University Journal of Natural & Applied Sciences
This research is based on the inventory of data and information on daily and monthly temperatures from 2000 to 2017, where we analyzed the data obtained from NASA about the city of Mukalla for the specified period of time. Using equations, the average daily temperature was calculated from the daily temperature data multiple times equivalent to eight times a day. Monthly and annual averages were calculated using statistical methods. The results clearly show the extent of the change in the temperature rate during the study period. It is noted that there was an increase in the rate of temperature change …
Improving Accurate Candidates For Missing Data Using Benefit Performance Of (Ml-Som), Abeer Abdullah Al-Mohdar, Mohamed Abdullah Bamatraf
Improving Accurate Candidates For Missing Data Using Benefit Performance Of (Ml-Som), Abeer Abdullah Al-Mohdar, Mohamed Abdullah Bamatraf
Hadhramout University Journal of Natural & Applied Sciences
Missing data is one of the major challenges in extracting and analyzing knowledge from datasets. The performance of training quality was affected by the appearance of missing data in a dataset. For this reason, there is a need for a quick and reliable method to find possible solutions in order to provide an accurate system. Therefore, the previous studies provided robust ability of Self Organizing Map (SOM) algorithm to deal with the missing values [6, 20]. However, it has a drawback such as an error rate(ERR) in the missing values that increase huge dataset. This study is mainly based on …
Kinetic, Equilibrium And Application Studies For Removal Of Methylene Blue From Aqueous Solution Using Sesbenia Dates Activated Carbon, Mohammed Saleh Bashanaini, Gameel Ahmed Baghaffar, Waheeb Abdellah Bin Frejan
Kinetic, Equilibrium And Application Studies For Removal Of Methylene Blue From Aqueous Solution Using Sesbenia Dates Activated Carbon, Mohammed Saleh Bashanaini, Gameel Ahmed Baghaffar, Waheeb Abdellah Bin Frejan
Hadhramout University Journal of Natural & Applied Sciences
In the present work, sesbenia dates as local agricultural waste has been successfully used for the preparation of activated carbon (AC) by sulphuric acid. This sulphuric acid based activated carbon (SD) and (MSACS) were used for the removal of one cationic dye viz., methylene blue (MB) from aqueous solutions. The structure and physical and chemical properties of (SD) and (MSACS) are investigated using (FTIR) and (SEM) analysis and pH surface and Boehm titration. The effect of the differential experimental parameters controlling the adsorption of dye onto (SD) and (MSACS), were thoroughly investigated, such as the effect of pH, initial dye …
On 𝜃- -Closed Sets And 𝜃- -Continuous Functlons, Amin Hamoud Saif, Nahid Mohammed Al-Showhati
On 𝜃- -Closed Sets And 𝜃- -Continuous Functlons, Amin Hamoud Saif, Nahid Mohammed Al-Showhati
Hadhramout University Journal of Natural & Applied Sciences
In topological spaces, the class of 𝜃-closed sets and 𝜃-continuous function have been introduced by Velicko and Fomin respectively. The purpose of this paper is to introduce and study these notions in grill topological spaces by giving the new classes of 𝜃- -closed sets and 𝜃- -continuous functions in grill topological space.
Electro-Organic Synthesis Of Schiff-Bases And Azo-Schiff Bases By Electrochemical Reduction Of The Nitro Group Group In Different Media, Siba Naseef, Deep Bakair, Rushdi Mador
Electro-Organic Synthesis Of Schiff-Bases And Azo-Schiff Bases By Electrochemical Reduction Of The Nitro Group Group In Different Media, Siba Naseef, Deep Bakair, Rushdi Mador
Hadhramout University Journal of Natural & Applied Sciences
In this research synthesized amino is derivative of Schiff-bases by using electrolysis cell. Electrochemical reduction of para-nitroaniline and electrocatalysed condensation have been carried out at zinc electrode and anode from coal in the presence of potassium chloride as supporting electrolyte in water/methanol solution, and in the application of 20V voltage, where interaction is in two stages: the first stage involves the electrochemical reduction of nitro group and get the amino and the second phase also, azo Schiff was synthesized between para-nitroaniline and metoxybenzealdehyde by electrolysis method, which was supplied with a zinc electrode as cathode to perform electrochemical reduction in …
Splitting-Up Technique And Cubic Spline Approximations For Solving Modified Coupled Burgers' Equations, Anwar Abdulla Bassaif
Splitting-Up Technique And Cubic Spline Approximations For Solving Modified Coupled Burgers' Equations, Anwar Abdulla Bassaif
Hadhramout University Journal of Natural & Applied Sciences
In this paper, a finite difference scheme based on the splitting-up technique and cubic spline approximations is developed for solving modified coupled Burgers' equations. The accuracy and stability of the scheme have been analyzed. It is found that the scheme is of first-order accuracy in time and second-order accuracy in space direction and is unconditionally stable. The numerical results are obtained with severe/moderate gradients in the initial and boundary conditions and the steady state solutions are plotted for different values of given parameters. It is concluded that the resulting scheme produces satisfactory results, even in the case of very severe …