The interplay of species in a polluted environment is one of the most critical aspects of the ecosystem. This paper explores the dynamics of the two-species Lokta–Volterra competition model. According to the type I functional response, one species is affected by environmental pollution. Whilst the other degrades the toxin according to the type II functional response. All equilibrium points of the system are located, with their local and global stability being assessed. A numerical simulation examination is carried out to confirm the theoretical results. These results illustrate that competition and pollution can significantly change the coexistence and extinction of each species.
In this work, a joint quadrature for numerical solution of the double integral is presented. This method is based on combining two rules of the same precision level to form a higher level of precision. Numerical results of the present method with a lower level of precision are presented and compared with those performed by the existing high-precision Gauss-Legendre five-point rule in two variables, which has the same functional evaluation. The efficiency of the proposed method is justified with numerical examples. From an application point of view, the determination of the center of gravity is a special consideration for the present scheme. Convergence analysis is demonstrated to validate the current method.
The dimensions of bubbles were measured in a stirrer tank electrochemical reactor, where the analysis of the bubble size distribution has a substantial impact on the flow dynamics. The high-speed camera and image processing methods were used to obtain a reliable photo. The influence of varied air flow rates (0.3; 0.5; 1 l/min) on BSD was thoroughly investigated. Two types of distributors (cubic and circular) were examined, and the impact of various airflow rates on BSD was investigated in detail. The results showed that the bubbles for the two distributors were between 0.5 and 4.5 mm. For both distributors at each airflow, the Sauter mean diameter for the bubbles was calculated. According to the results, as the flow rate raised, the bubb
... Show MoreThe importance of vibrations in rotating rotors in engineering applications has been examined, as has the best approach to interpreting vibration data. The most extensively used analytical approaches for rotating shaft vibration analysis have been investigated. In this research, a detailed study was made of the Rayleigh and Dunkerley methods due to their importance in the special calculations to find the amplitude of vibrations in the rotation system. The multi-node method was used to calculate both Dunkerley's and Rayleigh's methods. An experimental platform was built to study the vibrations that occur in the rotating shafts, and the results were compared with theoretical calculations and with different distances of the bearings. It pro
... Show MoreBackground: Oocytes are susceptible to alterations in the various fatty acid contents of follicular fluid (FF), which may influence maturation and embryogenesis. Different fatty acids exert various effects on intracytoplasmic sperm injection (ICSI), which needs further studies to uncover the involved mechanisms. Objectives: To assess FF fatty acids in women undergoing ICSI and to correlate them with ICSI parameters, namely the total count of aspirated oocytes, oocyte maturation rate, fertilization rate and percentage of good-quality embryos. Methods: Fifty women undergoing ICSI were enrolled in this cross-sectional study. FF samples were collected during oocyte retrieval and were analyzed for fatty acids using gas chromatography. Fa
... Show MoreSoursop is useful in treating diseases and the bioactive components of the fruit are beneficial in the treatment of gastrointestinal parasites. Annona muricata contains flavonoids, phenolic acids, and tannins in its leaves, pulp, and seeds. The current study provided an accurate analytical method for the pharmacologically active components, including glutathione, potassium, and vitamin B6, in soursop fruit samples of soursop using high-performance liquid chromatography and atomic absorption spectrometry. The fruits of the soursop were cleaned, peeled, and sliced into tiny pieces. The juice was chilled and kept in glass bottles. After blending the fruits with distilled water, they were placed on a magnetic stirrer and left for 72 hours. For
... Show MoreBackground: Oocytes are susceptible to alterations in the various fatty acid contents of follicular fluid (FF), which may influence maturation and embryogenesis. Different fatty acids exert various effects on intracytoplasmic sperm injection (ICSI), which needs further studies to uncover the involved mechanisms. Objectives: To assess FF fatty acids in women undergoing ICSI and to correlate them with ICSI parameters, namely the total count of aspirated oocytes, oocyte maturation rate, fertilization rate and percentage of good-quality embryos. Methods: Fifty women undergoing ICSI were enrolled in this cross-sectional study. FF samples were collected during oocyte retrieval and were analyzed for fatty acids using gas chromatography. Fa
... Show MoreUnder-reamed piles are piles with enlarged bases, which may be single bulb or multi bulbs. Such piles are suitable for resisting considerable soil movement of filed up ground, soft clay, and loose sand and have the advantages of increasing the soil strength and decreasing the displacement. In the present study, the finite element method was used to analyse the performance of a single pile with under-reamed bulbs of different shapes, that is, single cone, double cone, and half and full sphere, embedded in homogeneous, poorly graded sandy soil. The model of under-reamed pile was made of reinforced concrete and the bulb located at the middle of the embedded length of the pile. The dynami
A new design of manifold flow injection (FI) coupling with a merging zone technique was studied for sulfamethoxazole determination spectrophotometrically. The semiautomated FI method has many advantages such as being fast, simple, highly accurate, economical with high throughput . The suggested method based on the production of the orange- colored compound of SMZ with (NQS)1,2-Naphthoquinone-4-Sulphonic acid Sodium salt in alkaline media NaOH at λmax 496nm.The linearity range of sulfamethoxazole was 3-100 μg. mL-1, with (LOD) was 0.593 μg. mL-1 and the RSD% is about 1.25 and the recovery is 100.73%. All various physical and chemical parameters that have an effect on the stability and development of
... Show MoreThe mechanical design of elevator elements is always performed by international standards. The engineer selects the appropriate elements of elevator according to catalogues without knowing scientific details. Therefore, a theoretical analysis is achieved at two operating conditions for guide rails (1) safety gear operation, and (2) running condition with the loads unevenly distributed on the elevator car. The guide rail is considered a continuous beam with variable supports. Then the British code is listed showing the equations used in it.
The theoretical equations showed that guide rails are never subjected to stress in simultaneous combined buckling and bending in the plane, where the bending moment is exerted. It is always a c
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