http://dspace-su.server.ly:8080/xmlui/handle/123456789/2146 2026-05-01T12:46:39Z 2026-05-01T12:46:39Z Jaffalah J. Amhalhil http://dspace-su.server.ly:8080/xmlui/handle/123456789/2208 2024-12-02T19:59:48Z 2021-01-01T00:00:00Z

Oscillations of Solutions for Nonlinear Differential Equations Jaffalah J. Amhalhil It is know that many problems in physics, in the study of chemically reacting systems, in celestial mechanics and in other fields of science can be modelled by second order nonlinear differential equations. Therefore, the asymptotic and oscillatory properties of solutions of such equations have been investigated by many authors. In this paper our aim is to present some new sufficient conditions for the oscillation of all solutions of the nonlinear differential equations of the form (r(t)y (x(t))x(t)) + g1 (t, x(t)) = 0 Our new results extend and improve a number of existing oscillation criteria. Further, Our main results are illustrated with examples.

2021-01-01T00:00:00Z Ghaith Mansour Imhamed S Abu Laeg Ekasit Nugoolcharoenlap http://dspace-su.server.ly:8080/xmlui/handle/123456789/2204 2024-12-02T19:55:42Z 2021-01-01T00:00:00Z

Tunable Microstrip Bandpass Filter with Wide Tuning Range Ghaith Mansour; Imhamed S Abu Laeg; Ekasit Nugoolcharoenlap A tunable microstrip bandpass filter is presented. The filter is of a third order and based on general Chebyshev filtering response. It consists of three short-circuited microstrip line resonators whose length is λ/8 at the centre frequency of 1.5 GHz. The frequency tuning is achieved by connecting variable capacitors to the end of the resonators. The tuning range extends from 1.1 to 2.5 GHz. The insertion loss is better than -1 dB within the operating range. The proposed bandpass filter is designed and simulated using CST® software package. The simulated results demonstrate a good frequency selectivity, wide tuning range and low insertion losses.

2021-01-01T00:00:00Z Abdelrahman Ali H. Ali Zenb Mousa Abl Alrahman Omlhana Husayn Alfeetori Khaled A. M. Khalfalla Najat A. B. Mohammed Nouryia M. B. Lodi Samerah M. A. Alsdaee http://dspace-su.server.ly:8080/xmlui/handle/123456789/2202 2024-12-02T19:52:44Z 2021-01-01T00:00:00Z

Nanotechnology: A New Sight Toward the Future Abdelrahman Ali H. Ali; Zenb Mousa Abl Alrahman; Omlhana Husayn Alfeetori; Khaled A. M. Khalfalla; Najat A. B. Mohammed; Nouryia M. B. Lodi; Samerah M. A. Alsdaee Lately, all over the world, increasing attention has been paid to highlight the importance of employing Nanotechnology in various practices and industries. Nanotechnology seems to be the first rank among the priorities of scientific researches. The present study concentrates on the awareness of Nanotechnology. It was conducted as a partial fulfillment of the requirement for (B.Sc.) degree in the chemistry department in Sirte university in 2017 - 2018. It aims to discover the extent of general knowledge regarding Nanotechnology and its advantages. Information was collected in analytic descriptive method. A survey has been applied by using a questionnaire and library research. A sample of 95 participants was undertaken in Sirte university. Data was analyzed using the statistician program (SPSS). The result shows that the majority of respondents (33.7%) have no idea about Nanotechnology. However, some of them trust that the advantages of Nanotechnology are more than its disadvantages. Also, as an interesting outcome, most of the answers (84.2%) approve that; participants have been stimulated to quest about the technology and its benefits. This paper confirms the view which announces Nanotechnology as a component of the world's future leading to a new industrial revolution.

2021-01-01T00:00:00Z Mustafah M. Abdullah Ahmad T. M. Fayez, Ibrahim A. Saleh http://dspace-su.server.ly:8080/xmlui/handle/123456789/2199 2024-12-02T19:49:20Z 2021-01-01T00:00:00Z

Structural properties of polycrystalline diamond films prepared by Hot-filament Chemical Vapour Deposition technique Mustafah M. Abdullah Ahmad; T. M. Fayez, Ibrahim A. Saleh Polycrystalline diamond layers were deposited on silicon substrate using the hot filament chemical vapour deposition (HF-CVD) technique with a mixture of propane-butane/hydrogen as a working gas. The morphology and structural properties were observed using scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectroscopy, respectively. The SEM measurements have executed on films at different process duration. The films showed a pyramid shape with a preferential (111) morphology. The XRD patterns of films exhibited the whole spectra of diamond structure. At filament temperature of 2140°C and 2200°C followed with increasing the gas flow and deposition duration, the reflection peak at (111) is sharp and has a high intensity indicating good crystalline films. The crystalline size of films increased from 50nm to 255nm as process duration is decreased from 34h to 13h and the filament temperature is increased up to 2150°C. On the other hand, an increase of filament temperature, gas flow rate and process duration to 2200°C, eight sccm, and 42h, respectively, the film showed the smallest crystalline size value of 29 nm among the other samples. The stress values of films were estimated using the Raman spectrum. The films have comparative stress generated during cooling down to room temperature.

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