Digital Repository for Faculty of Science

Abstract

Five symmetrical Schiff base ligands[four bi-dentate and one tetradentate(L3- L7)] and two un-symmetrical bi-dentate and tri-dentate (L1-L2) ligands with the Nitrogen and oxygen chromophore were isolated inpure form and good yield. The ligands were fully characterized by elemental analyses, melting point, IR, H1- &13C- NMR, and mass spectra.The Schiff bases L1 and L2 were successfully coordinated to Pd(II) and VO2+ ions respectively and these complexes were characterized using elemental analyses, IR and mass spectra. The interesting result by mass spectrum of VO2+ complex of L2 shows parent peak at 524 confirming that the formula of the complex as [VOL2(ac.ac.)2H2O] in which the complex has an octahedral geometry.The symmetrical Schiff bases (L3-L7) were also successfully coordinated to Nickel (II), Copper (II), Lead (II), Cadmium (II), and Mercury (II) ions to form their corresponding complexes. The total twenty five metal (II) XI Schiff base complexes of (L3-L7) were isolated. These complexes were characterized by elemental analyses, melting points, IR, mass spectra technique. 1H &13C-NMR Spectra in DMSO d6 for Pb, Cd, and Hg complexes show the expected number of peaks with deferent chemical shift comparing with the free ligands in the same solvent. The interesting result by mass spectrum of Ni(L7)2 complex compred with of L7 spectra shows parent peak at 977 confirming that the ligand L7 has lost one proton to give the desire complex in square planar geometry.
حميدة أحمد سالم العباني (2015)

Abstract

In practice, most SoCs are multiprocessor systems-on-chips (MPSoCs) because it is too difficult to design a complex system-on-chip without making use of multiple CPUs. MPSoCs are the latest picture of very large scale integration (VLSI) technology. The architecture of the system is generally tailored to the application rather than being a general-purpose chip. This in turn enforces designers to move beyond logic design into advanced computer architecture and parallel processing. In such architectures, cores are integrated via a custom or commercial interconnection network with a controller, timing and a function interface to the external world. Current state-of-the-art SoCs already embeds typical sub-systems such as digital signal processors (DSP), RAM, ROM, MPEG cores.The main goal of this thesis is to design an efficient switch for Fat-tree interconnection networks. In addition a useful survey study for interconnection networks architectures, technologies and routing algorithms was provided. The survey included in some details commonly used switching methods and virtual channel arrangements. The proposed switch structure has been validated by a software model.A set of algorithms and procedures have been developed to facilitate the switch functionality. Those procedures include the control of transmission of the packets from switch input buffer to switch output buffer and transferring packets from switch output buffer to neighboring switch input buffer. While the input/output link controllers take care of buffer assignments to flits (packet) and deals with buffer organization. More over, the algorithms include (i) the routing algorithm which is the least common ancestor routing algorithm, (ii) arbitration algorithm that based on round-robin technique.Therefore in this thesis we have proved the correctness of the functionality of the proposed switch in software model that have been written in C++ language. The obtained simulation results of the switch functionality in fat-tree of 16 nodes definitely declare the correctness of the proposed arbitration scheme as well as showing the efficiency of the routing algorithm. Finally, we can say that the fat-tree interconnection network is very good candidate to implement future NoC connectivity for current and future multiprocessor systems-on-chips (MPSoCs) designs due to its modular, flexible and regular structured design. In turn, these features are suitable as well for VLSI realizations.
أسماء شعبان العصار (2010)

Abstract

Laser surface treatment of materials is one of the most effective methods of improving properties and performance of metallic articles. This technique proved its capabilities and advantages in comparison with other methods of surface treatment As an example, it has been shown that the distortion caused by this type of treament is at least one order of magnitude smaller than by that due to other techniques. Moreeover, laser beam is capable of reaching practically any point of the surface whatever it is narrow or difficult to reach by other techniques. The current work investigates the possibility of improving certain mechanical properties of both technically pure aluminum and A1-4o/oSi alloy, using ruby laser of 3 xl 05 W/cm2 power density. The surface of the investigated materials has been impregnated by SiC particles of varying size ranges, with or without firrther alloying of the surface with Titanium powder addition to the impregnated mixture. The laser treatment included coating one surface of each specimen of SiC particles by means of a binder added at a certain ratio (with or without Ti additions to the mixture). The coated surface was then subjected to the laser beam, which melted a layer I OO-150Jilll thick. Due to hydrodynamic effects the melt mixes with SiC particles and dissolves some or all of the added Ti and rapidly solidifies forming a thin layer distinct in properties from the original surface. Two groups of specimens were used in this study. The first group was treated by impregnating SiC particles of one size range with or without Ti-additions. Various numbers of laser pulses have been applied increasmg in a geometrical progression (1-2-4-8 pulses). These specimens were used for the study of the effect of varying: 1) the chemical composition of the substrate materials ;2) the number of laser pulses :and 3) the effect of Ti additions to the impregnating mixture on the microstracture and microhardness of the treated zones. The specimens of the 2nd group were coated by a square network of laser treated zones each 1.5mm in diameter. These specimens have been used to study :1) the effect of the chemical composition of the substrate material ;2) the size of the SiC particles and 3) the effect of Ti addition to the mixture on the wear perfomance of the treated specimens. Identical specimens have been used to determine the solubility of Si into the aluminum phase during the test by means of x-ray diffraction. This dissolved Si is partly responsible for the increase ID microhardness and wear resistance of the investigated specimens. The results show the positive effect of the applied treatment on the properties and preformence of technically pure AI and A-4%Si alloy. The materials microhardness within the treated zones has been increased by a factor of 2.7 and 2.4 for pure Al and Al-4%Si substrates, respectively. The microstructure of the treated zones became more homogeneous and the penetration of SiC particles into them has been increased with increasing the number of the applied laser pulses. The wear resistance of pure Al has been increased by a factor of 73.6 due to laser assisted impregnation, while that of AI-4%Si by afactor of 42.5. Wear resistance was found to increase with I) Si addition to the base metal; 2) Ti addition to the impregnated mixture, and 3) increasing the SiC particle size. This thesis is a part of a wider study that deals with surface treatment of Al and AI-Si alloys undertaken in our laboratry. Such study proved how effective the laser alloying and impregnation of such alloys in improving some of their mechanical properties which are important in industrial application, especially in internal combustion engine design.
أسماء عبد الرزاق وهرة (2002)

Abstract

Libyan cities have experienced a period of rapid urban expansion in the past decades. Urban growth as an example has been the focus of urban researches for a long time. Due to the complexity of the urban growth process, it’s very difficult to model urban growth using traditional urban models. Recently, urban researches are keen on a new technology, Remote Sensing. Remote Sensing technique was applied in many aspects of life, due to ability of covering and representing the real world around us. In urban research, field researches set up many applications to simulate the urban phenomena such as sprawl process, landuse change trends, landcover...etc. Remote sensing technology helps to extract and organize the data about such phenomenon. In addition to understand their spatial relationships, and provides a powerful means to planners and decision makers for analyzing and information about a place or a phenomenon. This will have great impact on the quality of the decision-making. The study uses Spot 5 images, topographic maps which derived from aerial photographs for the year 1980. The remote sensing image interpretation and change detection to review the urban expansion for the study area in (1980 and 2009).Spot satellite image of 2009 and Landuse maps1980 will be used to derive information on urban land use in the study area. The visual interpretation is used to extract landuse. The mutual use of Remote Sensing (RS) and Geographic Information System (GIS) describes the overall physics changes of the study area. This effort can be considered as an application case in this field (RS-based town planning information system), where this thesis show how that system can be useful of using this technology and supporting the sector by developing a model that can support the process of planning and maintain what remained of the agricultural lands to prevent them from encroachment by the urban growth.
حسين علي أحمد زيدان (2010)

Abstract

Murzuq Basin is located in south western of Libya. The theses represent a study of the concession (NC-174) area in Murzuq Basin. This theses consists of two major parts; the first part investigates the geophysical seismic interpretation of the concession (NC-174) area including the Elephant field area, and as a result the pressure of Elephant oil field (western part of (NC-174) concession) is not superior so that it needs to inject water interested in the oil structure. Therefore, the second part of theses provides better understanding of the aquifers study (Aquifers volume, extensions, isolation) within the concession (NC-174) area to be used for water injection of the oil reservoir of Elephant filed. The water injection method used in oil production is where water is injected back into the reservoir usually to increase pressure and thereby stimulate production. In this theses most visible horizons are interpreted by charisma software focused on the all aquifer water and (seal, reservoir, basement) formations, and the seismic interpretation includes all of the available 2-D and 3-D seismic data.The geophysical seismic interpretation method is used to cover the concession (NC-174) area, concentrates on the Elephant oil field using all the available seismic versions datasets. The main result of this thesis indicates that the Ordovician sandstone (Mamuniyat formation) is high-quality oil reservoir in the Elephant oil field and can be represent a saline aquifer outside the Elephant oil field structure (scorpion area_ southeast of Elephant oil structure ) either to the northern or southern hanging wall unless the main faults are not sealing. The Mamuniyat reservoirs sourced by hot shales of the Lower Silurian Tanezzuft Formation.
عادل المبروك التوجير (2009)

Abstract

Seven geological sections have been examined and sampled with emphasis on sedimentological & diagenetic processes within Abu Ghaylan Formation and the contact relationships with the underlying Abu Shaybah and overlying Kiklah Formations. Based on current detailed field loggings and microscope investigations, 10 facies are recognized within Abu Ghaylan Formation. The lowermost succession characterised by an overall transition from continental fluvially dominated deposits of the Abu Shaybah Formation into transitional to marginal marine, tidal flat deposits of the Abu Ghaylan Formation upward. The transitional nature of this lowermost part succession is demonstrated by interbeddings of claystone, sandstone and fossiliferous facies arranging in coarsening up cycle, in which most probably deposited in estuary / beach environment.The Abu Ghaylan Formation generally wedges laterally eastward and exposes intermittently east of Wadi Ghan area resulting of syngenetic uplift of Wadi Ghan area followed by erosion (ElHinnawy & Cheshitev, 1975). A slightly earlier uplift and greater erosion in a westward sloping basin of deposition near the close of the Early Jurassic and Early Cretaceous times is suggested by Fatmi & Sbeta (1991). The current study reveals that several exposure surfaces are demonstrated within Abu Ghaylan Formation suggesting uplifting and erosion episodes interrupted Abu Ghaylan Formation, where a restricted distribution of Abu Ghaylan may suggest a local tectonic overprint.Although the overall impression is that the base beds of Kiklah Formation starts with sandstone and red clay beds as channel infill deposits above Abu Ghaylan carbonate unit with surface of unconformity, however, based on current close investigation, a sequence characterized by interbeddings of carbonate and greenish clay overlying Abu Ghaylan Formation with surface of unconformity and gradationally overlain by sandstone beds should be introduced as separate unit attributes to Kiklah Formation.The current study emphasizes and supports a solution collapse origin for the breccias and introduces better insight into architecture and geomorphology of the breccias bodies that are exposed in the area of study. The dissolution of evaporites is considered responsible for all breccias development in this stratigraphic interval. According to the occurrence mode of breccias, the breccias intervals have been divided into two main parts; a lower section of strata that contains collapsed paleocaves and an upper section of strata that is deformed to varying degrees due to the collapse and compaction of the section of paleocave-bearing strata. The sharp flat base, inverse grading, V-shaped/ sag structures and irregular undulating top of brecciated bodies are recognized within Abu Ghaylan Formation and typically characterize solution collapse processes. Based on field study and architecture relationships, five distinctive karst facies are recognized in the area of study.The early diagenetic genetically related processes probably interrupted the deposition of Abu Ghaylan Formation is a most possible assumption for the origin and timing of breccias formation.
أحمد أبوبكر الحلو (2015)

Abstract

The area of study is located in the southeastern part of Block NC98 and is informally named C-Structure area, and it is completely situated in the center of Al Hameimāt Trough, South East Sirt Basin, Libya. The main reservoir rock in this structure is the Upper Nubian Sandstone Member, whereas the Reworked Sandstone Unit and Transitional Beds are considered as secondary reservoir rocks. These reservoirs are mainly composed of sandstone to argillaceous sandstone. The Upper Nubian Sandstone reservoir quality is adversely affected by volcanic rocks especially the thick intercalation of volcanoclastics within the Upper Nubian Sandstone. The Upper Nubian Sandstone Member was deposited during Early Albian times. The Reworked Sandstone Unit was possibly deposited in Cenomanian? to Turonian times and may be related to the overlying Transition Beds.Up to date, four wells have been drilled in this structure (C1-NC98, C2-NC98, C3-NC98 and C4-NC98) and were targeting the clastic reservoirs of the Upper Nubian Sandstone and/or overlying Upper Cretaceous Transitional beds and Reworked Sandstone unit. Only C1-NC98 and C2-NC98 wells have tested significant hydrocarbon in the Upper Nubian and Reworked Sandstone unit whereas C3-NC98 and C4-NC98 wells have tested no hydrocarbon in both reservoirs and are abandoned as dry wells. This study is aimed to validate the stratigraphical aspects, depositional environment and reservoir quality assessment in order to decipher the reasons of drilled dry holes. The obtained results are anticipated to provide valuable geological information for the current and future prospect evaluation in the area. All available wire line logs of C wells (C1-NC98, C2-NC98, C3-NC98 and C4-NC98) and adjacent wells have been used to correlate the stratigraphy of the Pre-Upper and Upper Cretaceous silisiclastic sediments in the area of study.Representative core samples across the reservoir rocks of the candidate wells have been laid down for core description. The acquired results have been integrated with conventional core analysis and petrographic results to investigate the lithofacies characterization and depositional environment in order to sub-divide them into different lithofacies.Different types of geological maps have been prepared in this research (e.g. stratigraphical/structural cross sections, subcrop maps, isobach maps, structure contour maps and etc.) to delineate the formation extension and correlation. Burial history diagrams across all depositional sequences in the candidate wells were also prepared to identify the depositional scenario and to estimate the time span of tectonic subsidence along the depositional sequences.The results of all available geological studies which recently have been carried out by Waha Oil Company in the area of study and adjacent areas have been reviewed, elaborated and integrated with the results of this study to assess the discussion and final conclusion. The final results of sedimentological study indicates that there is no major effect of diagenetic processes on the reservoir rocks during and after the deposition. As a consequence, C3-NC98 and C4-NC98 wells were drilled in an area of poor reservoir quality of Reworked Sandstone and Upper Nubian reservoirs due to the existence of thick sequences of clay and siltstone which were mostly deposited in levee and over bank sub-environments of likely combined braided and meandering river. Whereas, C1 and C2-NC98 oil wells were drilled in an area of good reservoir quality of Reworked Sandstone and Upper Nubian Sandstone reservoirs where the sand bars sub-environment are deposited as a thick sequence of clean sands carrying the genetic of good reservoir properties. Therefore, the reservoir rocks in this area have different properties due to different sub-environment of deposition. This new results will probably assess the prospect generation and evaluation for the future drilling activity in the area of study.The encountered volcanoclastic sediments in well C2-NC98 reveals that this sediment is likely transported by river from the area of volcanic eruption to the area of deposition rather than in situ eruption. This type of volcano is likely applied to cinder cone volcano type where the pyroclastic fragments are not cemented together and thus easy to erode. Therefore, the intercalation of volcanoclastic sediment in Upper Nubian Sandstone has no marked effect in the reservoir rocks.Burial history curves of wells C1-NC98, C2-NC98, C3-NC98 and C4NC98 indicate three major subsidence events took place during Early Cretaceous time (Early Aptian - Early Albian), Late Cretaceous time (Turonian - Maastrichitian) and the Palaeocene - Eocene subsidence. However, Plaeocene - Eocene subsidence shows the highest subsidence rate with comparison to the other two subsidence rates.
محمد عمار هامان (2015)

Abstract

The basaltic Intrusions of the Central Jabal Nafūsah Foothills which extend from NW Wādi Zāret to NE Wādi Ghān Dām are part of the latest stage of Gharyān Volcanic Province (GVP). These intrusions are classified on basis of their shape and mechanism of emplacement into four kinds of volcanic bodies. These are; sheets (dykes and a sill), dykes associated with volcaniclasts, volcanic cone and lava mounds. Generally, the dyke emplacements are restricted only to the area between Wādi Zāret to Abū Ghaylān, while the other forms extend from Rās al Mazūl Dome to Wādi Ghān Dam. The more differentiated rocks are restricted to the area between Rās al Mazūl Dome and Wādi Ghān. Farther west towards Wādi Zāret, ultramafic xenoliths and magnesium-number increase, suggesting closer proximity to the source. The rocks are essentially alkaline with within Intraplate signatures. They straddle the composition from picrites, basanites, alkali basalts through hawaiites, mugearite to benmoreites with a compositional gap between the last two types. Generally, the phenocrysts are represented by foresteritic olivine, Cadiopsidic pyroxene, magnesiotaramitic amphibole, plagioclase, K-feldspar and titanomagnetite. The chemical composition of the mafic minerals indicates that they are high pressure phenocryst phases. The most primitive picrites satisfied the criteria of primary mantle melts. The rocks are generally, enriched in LILE suggesting an enriched mantle source. The studied rocks were grouped into five groups based on incompatible trace element ratios; Group-A includes picrite, basanites and hawaiites, and Group-B includes picrite (Z-3), basanites , alkali basalts, and hawaiites, while Group-C is formed of hawaiites, Group-D is composed of mugearite and Group-E is made up of benmoreites. Picrites and basanites of these rock have high Mg-number (>0.64), high Cr and Ni contents and strong light rare earth element enrichment, but systematic depletion in Rb, K and Ba relative to trace elements of similar compatibility in anhydrous mantle. Alkali basalts and more differentiated magmatic rocks have lower Mg-number and lower abundances of Ni and Cr, and have undergone fractionation of mainly olivine, clinopyroxene, Fe–Ti oxide, amphibole and plagioclase. The variation in the concentrations of major, trace, rare earth elements, and incompatible element ratios in the rock samples demonstrate the heterogeneous character of their source region. Such heterogeneity can be interpreted by the involvement of a heterogeneous mantle reservoir to different degrees of partial melting. The REE data require residual spinel stability peridotite field in the source and constrain the melting process of Group-C and Group-D to 2% to 3.5% degrees of melting respectively, Group-A and Group-B both to 5% degree of partial melting while Group-E to 10% degree of partial melting of spinel lherzolite xenoliths of Al Ourban area. Mass balance modelling of the major suggests two possible FC scenarios; Derivation of basanites and hawaiites of group-A from G-3 picritic parental magma. Derivation of Group-D and Group-E was also possible from these basanites. Derivation of basanites of Group-B from Z-3 picrite parental magma and simultaneous derivation of G-4 and QJ-1 alkali basalts from Z-3 picrite parental magma. V Simple mass-balance calculations suggest that the melting assemblages of picrites and basanites consisted of forsteritic olivine, diopsidic clinopyroxene, Ti-magnetite. While the alkali basalts and more differentiated magmatic rocks, mass-balance calculations suggest that the melting assemblages consisted of sodic plagioclase, magnesiotaramitic amphibole, diopsidic pyroxene, Ti-magnetite, K-feldspar with sub amounts of apatite and sphene.
سمية عون (2015)