http://hdl.handle.net/123456789/487 2026-06-02T05:31:24Z 2026-06-02T05:31:24Z M. L. Matta1 zeinab mohamed ibrahim ismail A. A. Hasan S. S. Elazab http://hdl.handle.net/123456789/227885 2026-05-29T13:30:21Z 2024-01-01T00:00:00Z

Title: Electrohydrodynamic Stability of Self-gravitating Fluid Cylinder Authors: M. L. Matta1; zeinab mohamed ibrahim ismail; A. A. Hasan; S. S. Elazab Abstract: Electrohydrodynamic Stability consists of a fluid cylinder with self-gravitation A self-gravitating tenuous medium surrounds it. that is permeated by a transversely variable electric field while being affected by self-gravitating forces, Capillary, and Electrical Forces is covered across all axisymmetric and (non)axisymmetric perturbation types. The problem is solved and all individual solutions are excluded. The model stabilizes as a result of continuous Electric field stability in all perturbation modes. In a narrow area of the axisymmetric perturbation. It has been established that self-gravitating and capillary forces have a destabilizing effect. However, the present model instability is improved and modified by self-gravitating and capillary forces' stabilizing effects in all large axisymmetric fields and (non)axisymmetric domains. Description: stability of fluid

2024-01-01T00:00:00Z Maysa Abdou Ali http://hdl.handle.net/123456789/227851 2026-05-29T12:28:24Z 2018-01-01T00:00:00Z

Title: الاستدلال غير الرتيب Authors: Maysa Abdou Ali Abstract: إن مشكلة إيجاد أليات استدلال فعالة وقادرة علي نمذجة استدلال الحس المشترك البشري هي واحدة من المشاكل الرئيسية للبحث والتنفيذ في مجال الذكاء الاصطناعي , لذا تعد دراسة الاستدلال غير الرتيب ذات أهمية كبري في وقتنا المعاصر, حيث إنه أداة مساعدة في فهم كيف يمكن استخدام برمجة المنطق في صياغة وحل مشكلات عديدة في مجال الذكاء الاصطناعي. بالإضافة إلي أنه يستخدم كأداة بسيطة و ذات كفاءة في نمذجة لغات لمواقف حينما يكون المرء بحاجة إلي التعامل بسرعة ومرونة مع المعلومات الناقصة والمتضاربة.

2018-01-01T00:00:00Z zeinab mohamed ibrahim ismail http://hdl.handle.net/123456789/227850 2026-05-29T12:25:50Z 2024-01-01T00:00:00Z

Title: Multiple oscillating layers of a double-perturbed interface with self-gravitate. Authors: zeinab mohamed ibrahim ismail Abstract: The multiple oscillating layers of a double perturbed interface under self-gravitating has been investigated for all the perturbation modes. This type of research may be found to examine oscillating on multiple layers with self-gravitating force. The stability criterion is constructed analytically explained and confirmed these results with the numerical computations. The governing equations (equation of motion and equation of continuous) are obtained, providing that the boundary conditions are appropriate. the fundamental equations are resolved, non-singular solutions are found using the proper boundary circumstances, also, derived the total second order differential equation. The difference between these two states, stable and unstable, relies on the value of densities. In this point, the gravitational instability of the current model, which forms the basis of this work, will be decreased, The streaming is unstable. The gravitationally stable and unstable zones are discovered and graphically displayed. The triple fluid layers' weight force and densities ratios contribute significantly to the unstable nature of the current model. Description: stability of fluid

2024-01-01T00:00:00Z Hager Y. Ali Maha Rabea Abu-Serea Maysara E. Aboulfotouh Azza Aly Aly Abouhussein Ghada A. Mahmoud http://hdl.handle.net/123456789/227630 2026-05-26T08:35:31Z 2026-05-07T00:00:00Z

Title: 23.Radiation-synthesized PVP-CMC/CNT biodegradable hydrogels for efficient dye removal. Authors: Hager Y. Ali; Maha Rabea Abu-Serea; Maysara E. Aboulfotouh; Azza Aly Aly Abouhussein; Ghada A. Mahmoud Abstract: Methyl orange (MO) is classified as a recalcitrant and refractory xenobiotic, posing a significant threat to ecosystems due to its high toxicity and persistence. This highlights the urgent need for effective waste management. Biodegradable PVP-CMC hydrogel and PVP-CMC/CNT nanocomposite hydrogel were synthesized by copolymerization of carboxymethyl cellulose (CMC) and polyvinylpyrrolidone (PVP) via green gamma irradiation at 30 kGy, and 70:30 PVP: CMC, followed by incorporation of CNTs into the polymer matrix to prepare PVP-CMC/CNT. The biodegradation rates of the hydrogel and nanocomposite hydrogel are evaluated by quantifying weight loss in soil over 16 weeks. The biodegradation rates were 87 and 54.8% for the hydrogel and nanocomposite hydrogel, respectively. TGA shows that incorporating CNTs increases thermal stability and reduces overall PVP-CMC hydrogel breakdown by 30%. BET surface area increased to 5.653 m2 /g upon CNT incorporation. The highest removal % was 82.5 and 94.7% at pH=4, with pHpzc values of 7.9 and 8 for the hydrogel and the nanocomposite hydrogel, respectively. The PVP-CMC/CNT nanocomposite hydrogel achieved a maximum adsorption capacity (qmax) of 216 mg/g, demonstrating competitive performance compared to reported biopolymer-based adsorbents (typically 10–294 mg/g). Kinetic tests showed that the pseudo-second-order model best fit the adsorption process for the hydrogel and nanocomposite hydrogel, with R2 values of 0.98, confirming chemisorption as the rate-limiting step. These findings demonstrate the development of a sustainable hydrogel for water purification.

2026-05-07T00:00:00Z