Journal of natural sciences, life and applied sciences - مجلة العلوم الطبيعية و الحياتية والتطبيقية
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Published By The Arab Journal Of Sciences And Research Publishing

2522-3356, 2522-3356

Author(s):  
Wajde Essa Saleh, Mohammed Deep Wajde Essa Saleh, Mohammed Deep

In this research, the electrical and thermal conductivity of the compounds BaCl2-CuSO4-Na2CO3 - Ba6Na8C4Cl12O12 - Ba6Cu4S4Cl12O16 - Cu6Na8S6C4O36 and the solid solutions resulting from the interaction of these compounds with each other, using the thermal conductivity measuring device (ITP-M64) and electrical conductivity measurement device (the four paths) were studied. The results are different between superconducting materials and medium conductive materials (semiconductors).


Author(s):  
Ghazi Mahmoud Hasso Jawish, Rushdi Madwar, Francois Kara Bet Ghazi Mahmoud Hasso Jawish, Rushdi Madwar, Francois Kara Bet

In this research, two ether derivatives of phenolic azo dyes were synthesized via Williamson's reaction according to the SN2 mechanism. The prepared compounds were radically polymerized using (AIBN) as an initiator and their structures were identified by FT-IR and 1H-NMR. Furthermore, thermal properties of these polymers was made by (DSC). Bandgap energy have been calculated to indicate the ability of these polymers as optical semiconductors, it was 2.8ev, 2.4ev for P(AO2) and P(AON1) respectively. Beside the determination of refractive index, kinematic viscosity, density, and degree of Turbidity.


Author(s):  
Farid El-Wahidi, Khanniba Abdelilah, Saidi Mohamed Elmehdi, Farid El-Wahidi, Khanniba Abdelilah, Saidi Mohamed Elmehdi,

In Morocco, the dynamics of change in rainfall patterns have been underway for decades. It is characterized by increasingly frequent and violent hydrological and climatic events (floods and droughts). This work aims to study the peculiarities and mechanisms of the appearance of floods in the watershed of the Oudodou wadi (Province of Tiznit - southwestern Morocco) and conduct a frequency analysis of the extreme hydrological events associated with floods to estimate their probabilities and their return periods. In addition to the diagnosis of natural factors in the area studied and their relationship to the emergence of floods, the methodological approach adopted is divided into two stages. The first, known as historical, is based on the study of 8 flooding cases (1942 - 2014) and the delimitation of threatened areas through the representations of residents. The second step focused on analyzing the frequencies of extreme hydrological events to determine their severity and return periods. Analysis of the results showed that flood thresholds are always associated with the strength and concentration of rainfall, giving them a sudden behavior like summer floods. To guide the interventions of actors in the field, the areas threatened by flooding have been identified according to their degrees of severity. The recurrence of the flows was modeled using the GAMMA law which makes it possible to estimate the probability of occurrence of extreme events (floods) and the instantaneous flows corresponding to the return periods of 2, 5, 10, 20, 50 and 100 years. Biannual and five-year hydrological events correspond to instantaneous flows of 120 and 331 m3/s, while exceptional or even very exceptional cases have a return period of more than 50 and 100 years and correspond to instantaneous flows of 912 and 1035 m3/s.


Author(s):  
Eaman Al-Khouja, Magd Alfakhory, Hamza Hakmi Eaman Al-Khouja, Magd Alfakhory, Hamza Hakmi

The object of this paper is study the notions of weak Baer and weak Rickart rings and modules. We obtained many characterizations of weak Rickart rings and provide their properties. Relations ship between a weak Rickart (weak Baer) module and its endomorphism ring are studied. We proved that a weak Baer module with no infinite set of nonzero orthogonal idempotent elements in its endomorphism ring is precisely a Baer module. In addition, the endomorphism ring of a semi-projective weak Rickart module is semi-potent and the endomorphism ring of a semi-injective coweak Rickart module is semi-potent. Furthermore, we show that a free module is weak Baer if and only if its endomorphism ring is left weak Baer.


Author(s):  
Norah Ali Alshehri Norah Ali Alshehri

Prosopis Juliflora is an invasive shrub or tree native to South American countries. It is one of the most important exotic and invasive organisms that are spread in the Kingdom of Saudi Arabia. This study concentrates on investigating the widespread of Prosopis Juliflora  in Wadi Yiba، located in the southwest of the Kingdom، and given the possibilities offered by geographic information system (GIS) and remote sensing to help determine the areas of spread of the plant and its size، and to take the best capabilities، especially with regard to processing and analyzing large and diverse spatial information، the present research aims to use this in evaluating the current and future situation of the spread of plants in Wadi Yiba، and the extent of its impact on the environment، while suggesting appropriate ways to manage it. The research relied on the use of Landsat images، working with the subtraction method، and subjecting the images to the object-oriented classification، by taking 30 specimens for each cover and merging these specimens، and the layers of vegetation cover were derived using the normalized difference vegetation index (NDVI) for each year. The research concluded that there is a concentration in the spread of Prosopis Juliflora in the center and north of Wadi Yiba، especially in the city of Therban and villages of Al-Balqa’a، Al-Tala’i، Sabt Al-Jara، and Khamis Harb، with a spread along the valley to the estuary. At the end، the research recommended the establishment of a research center for the study of Prosopis Juliflora in Assir region، and an attempt to develop economic plans to benefit from Prosopis Juliflora in Wadi Yiba.


Author(s):  
Lara Kamal Jarouj, Anis Bilal, Nikola Abo Issa Lara Kamal Jarouj, Anis Bilal, Nikola Abo Issa

CT images were read and a 3D model of the tumor was created in the liver area, Then the values ​​of the radiation dose in terms of the depth resulting from (photons, neutrons and protons) were estimated and studied using the code (MCNP) after entering the data into it. The value of the radiation dose in terms of depth and curvature in photons, neutrons and protons radiation therapy was studied, from our findings in the research we note that protons are the best option for radiation therapy for high-depth liver cancer of photons and neutrons due to the lower dose at entry compared to the dose absorbed in the tumor area and its ability to deliver a greater amount of dose of neutrons and photons to the tumor area. We note that the values reached are acceptable for the treatment of tumors at a depth close to the surface. As for a large-depth tumor, it is necessary to increase high-energy radiation doses deep in the tumor area by accelerating proton therapy to protect natural organs from high-energy radiation doses.


Author(s):  
Suliman M. Mahmoud, Ahmad Al-Wassouf, Ali S. Ehsaan Suliman M. Mahmoud, Ahmad Al-Wassouf, Ali S. Ehsaan

In this paper, numerical spline method is presented with collocation two parameters for solving systems of multi-dimensional stochastic differential equations (SDEs). Multi-Wiener's time-continuous process is simulated as a discrete process, and then the mean-square stability of proposed method when applied to a system of two-dimensional linear SDEs is studied. The study shows that the method is mean-square stability and third-order convergent when applied to a system of linear and nonlinear SDEs. Moreover, the effectiveness of our method was tested by solving two test linear and non-linear problems. The numerical results show that the accuracy and applicability of the proposed method are worthy of attention.


Author(s):  
Edward S. Tannous Edward S. Tannous

We present here a model that explains in a simple, easy and summarized manner, the values, meaning and reasons for the force of gravity, using simple physical tools. According to this model, a gravitational field actually creates different energy levels, similar to the atom, around the center of mass of the gravitational source, and a transition between the energy levels results in the creation of the force of weight acting on each small body which is in the gravitational field. As the body approaches a gravitational field, its energy value decreases to a value of m0u2(R), proportional to the distance R between the centers of the masses, when u(R) is the magnitude of the self-speed of light vector (the progression in the time axis) of the small body, and its value decreases as it approaches the center of the origin of the field. This change in the energy levels is the cause of the force of gravity. A formula is obtained for the concept of potential gravitational energy and the variables on which it depends, and for the time differences between two frames that are in the gravitational field, taking into account the motion and location of each frame. It is obtained from this model that the speed of light is also a variable value as a result of the effect of the gravitational field.


Author(s):  
Rasha Houssam Khaddam Rasha Houssam Khaddam

The aim of the research is to develop a conception of the proposed model for Mantle upwelling (diapering) in the coastal region, as the results of this research showed the occurrence of Mantle upwelling regression under the coastal region during the Pliocene period, and this led to the occurrence of basaltic deposits in the Syrian coast during the Pliocene, where we note the center of the vaulting was under Qardaha and Safita, and the Mantle upwelling reached a depth of 35 km within the continental crust, where basalt rocks were formed as a result of partial melting of the upper mantle, and it is upwelled with low melting and differential degrees. Basalt rocks in the initial differential phase of the original basaltic silage.


Author(s):  
Zakiah Radhi Alhajji, Mohamed Elsayed Hafez Ali Zakiah Radhi Alhajji, Mohamed Elsayed Hafez Ali

Because of increased demand for electrical energy in the Kingdom of Saudi Arabia, which has resulted in an increase in carbon dioxide emissions, the electricity system in the Kingdom of Saudi Arabia is the largest in the Gulf region and the Arab world, with approximately 61.7 gigatons (GW) of peak demand and 89.2 gigatons (GW) of available capacity in 2018 of electricity power. It has grown rapidly over more than 20 years and has almost doubled in size since 2000. Where we observe that the total carbon dioxide emissions in the Kingdom of Saudi Arabia from 1990 to 2020; where shows rapid growth in emissions of carbon dioxide and greenhouse gases, as it was found that CO2 emissions in 1990 amounted to 151 million metric tons compared to 2011 when it reached about 435 million metric tons, and the increase continued until 2020 when it reached about 530 million metric tons. The comprehensive study relied on time series analysis to carefully analyze the electric energy productivity rate from fossil fuels and the significant amount of carbon dioxide emissions typically resulting from promptly burning fossil fuels to naturally produce electric energy. Therefore, the Kingdom of Saudi Arabia, through Vision 2030 and the Paris Agreement on Climate Change, looks to reduce the rate of carbon dioxide emissions in the field of electric power generation by diversifying the fuels used or replacing them with clean and renewable energy such as solar and wind energy.


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