Physics Commons^™

Differential Elliptic Flow Analysis Of Hadrons With Different Wuark Content In Simulated Pp Collisions, Elhussein Osama

Theses and Dissertations

According to current physics theories, it is assumed that in the first microsecond after the big bang, the universe was in a state of matter called Quark-Gluon Plasma (QGP), where the fundamental consistent of matters (quarks and leptons), were highly energetic, and floating around freely. Searching for such phase of matter; as the possible earliest signatures after the big bang, and among many other interesting experimental measurements, the jet quenching and elliptic flow are the most important ones, in the heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) experiments.

The azimuthal anisotropy …

Azimuthal Anisotropy Of Different Quark-Flavored Particles In High Energy "Simulated" Proton-Proton Collisions, Mahmoud Rateb

Theses and Dissertations

Anisotropic flow in high energy heavy-ion collisions is taken as a key evidence for the formation of QGP for brief seconds right after the collisions. Hydrodynamic models including QGP formation are accurate at predicting the azimuthal anisotropy of the produced particles at low transverse momenta. At high momenta however, hydrodynamic models predict no azimuthal anisotropy for particles of different masses and quark-flavors; the logic being that because of their high momenta, the particles pass through the media without having any time to have any reactivity. This is contrary to results from experiments where measurements of particles of different quark flavors …

Shadows Of A Schwarzschild Black Hole Surrounded By A Spherically Symmetric Dark Matter, Ahmad Ibrahim

Theses and Dissertations

In this thesis, using general relativity, the null geodesics and black hole shadow of a spherically symmetric configuration of a black hole (surrounded by a dark matter shell) are studied. First, the standard

results of the photon sphere of Schwarzschild de-Sitter black hole is revisited and analyzed more carefully. Secondly, using an ansatz (piecewise metric function) commonly used in the literature to describe the mass distribution of the spherically symmetric black hole - dark matter configuration, the null geodesics through vacuum and dark matter are analyzed. Assuming an observer located at a finite distance from the black hole outside the …

Atomistic Simulation Of Na+ And Cl- Ions Binding Mechanisms To Tobermorite 14Å As A Model For Alkali Activated Cements, Ahmed Abdelkawy

Theses and Dissertations

The production of ordinary Portland cement (OPC) is responsible for ~8% of all man-made CO2 emissions. Unfortunately, due to the continuous increase in the number of construction projects, and since virtually all projects depend on hardened cement from the hydration of OPC as the main binding material, the production of OPC is not expected to decrease. Alkali-activated cement produced from the alkaline activation of byproducts of industries, such as iron and coal industries, or processed clays represents a potential substitute for OPC. However, the interaction of the reaction products of AAC with corrosive ions from the environment, such as Cl-, …

Quantum Capacitance Investigation Of Different Tas2 Polymorphs For Energy Storage Applications – First Principles Study, Mahmoud Elattar

Theses and Dissertations

Energy is an essential requirement, which has a growing demand due to the growth of population and the world transformation into electronic. More than 70% of energy resources are fossil-fuel based which has an environmental impact due to the CO₂ emissions. Energy hubs for Fossil-fuel to electric energy conversion, controlled CO₂ emissions processing units, and energy storage system are key factors for a smooth transition to green energy without lack of energy supplies, where electrical energy storage systems (ESS) are key enablers to achieve that. One of the effective components which determines the ESS efficiency is the electrode …

Digital Computer Calculation Of Potential And Potential Gradient Around Bundled Three Phase Lines, Adel Lamei Stefanos

Archived Theses and Dissertations

No abstract provided.

Some Optical And Electrical Properties Of Cadmium Sulfide And Lead Sulfide Thin Films Prepared By Electron Beam Deposition, Achiri Celestine Tange

Archived Theses and Dissertations

No abstract provided.

Evidence For Quasi-Periodic Oscillations In The Recurrent Emission From Magnetars And Their Implications On The Neutron Star Properties And Equation Of State, Ahmed Monzer El Mezeini

Archived Theses and Dissertations

In this thesis, we present an analysis of highly magnetized neutron stars â magnetarsâ , in search for high frequency oscillations in the recurrent emission from the soft gamma repeater SGR 1806-20, and we discuss the physical interpretation of these oscillations and its implications on the neutron star properties and structure. We present evidence for Quasi-Periodic Oscillations (QPOs) in the recurrent outburst activity from the soft gamma repeater SGR 1806-20 using Rossi X-ray Timing Explorer (RXTE) observations. By searching a large sample of bursts for timing signals at the frequencies of the QPOs discovered in the 2004 December 27 giant …

Effect Of Pressure On The Electrical Transport And Structural Properties Of Ybnio3, Mostafa Gala El Dine Zeama

Archived Theses and Dissertations

No abstract provided.

On-Chip Nanoscale Plasmonic Optical Modulators, Abdalrahman Mohamed Nader Abdelhamid

Theses and Dissertations

In this thesis work, techniques for downsizing Optical modulators to nanoscale for the purpose of utilization in on chip communication and sensing applications are explored. Nanoscale optical interconnects can solve the electronics speed limiting transmission lines, in addition to decrease the electronic chips heat dissipation. A major obstacle in the path of achieving this goal is to build optical modulators, which transforms data from the electrical form to the optical form, in a size comparable to the size of the electronics components, while also having low insertion loss, high extinction ratio and bandwidth. Also, lap-on-chip applications used for fast diagnostics, …

Engineered Nanostructured Nitrogen-Doped Carbon Network (Ndc) Electrodes With Unprecedented Cycling Stability For Water Capacitive Deionization In Harsh Conditions, Soha Essam Anwar

Theses and Dissertations

Capacitive deionization (CDI) is a feasible low-cost desalination technique for low-to-medium (brackish) salinity water. However, cycling stability and regeneration of the CDI electrodes are the bottlenecks hindering the practical application of the technology on large scale. Oxidation of the electrodes during the sequential adsorption-desorption processes is one of the most challenging problems hindering their long-term cycling performance. Herein, we demonstrated the ability to design and fabricate exceptionally stable CDI electrodes via a one-pot pyrolysis protocol. The optimized pyrolysis of nitrogen-carbon precursors at different temperatures enabled the fabrication of carbon materials with a controlled amount nitrogen dopant (NDCs) with exceptional cycling …

Nanoengineered Materials For Energy Conversion & Storage Applications: A Density Functional Theory Study, Ahmed Biby

Theses and Dissertations

The conventional approach for the development of novel materials has become long relative to the desired product development cycle. Thus, the sluggish pace of the development of materials within the conventional approach hinders the rapid transformation of the scientific outcomes into useful technological products. To this end, the field of hierarchical materials informatics evolved to bridge this gap. In this field, the multiscale material internal structure is considered the starting point and the core of this approach. This being said, the density functional theory (DFT) was used to generate useful materials data for the advancement of the hierarchical materials data-bases …

Diffraction Of X-Waves From Multiple Rectangular Slits In An Opaque Screen, Ahmed El Saeed El Halawani

Archived Theses and Dissertations

No abstract provided.

Ab Initio Techniques For Methane, Nora Mohamed Hassan Mohamed

Archived Theses and Dissertations

No abstract provided.

Pulsed Laser Deposition Of Bismuth Telluride Compounds For Human Body Energy Scavengers, Ahmed Abdel Aziz

Archived Theses and Dissertations

No abstract provided.

Modeling And Design Of High Force Rfmems Contact Switches, Joseph Eid Estefanous Zekry

Archived Theses and Dissertations

This thesis describes the modeling and design issues of high force electrostatically actuated RFMEMS contact switches. Various reliability issues and challenges are associated with the design of RFMEMS contact switches. The reliability of microcontacts is of major importance in increasing the lifetime of such devices. A semi-analytical model based on the beam deflection theory is developed to calculate the contact force delivered by parallel-plate electrostatically actuated switch structures. The model is capable of fast and accurate static solution for complicated switch structures which are normally analyzed using finite element analysis techniques. High force designs are presented together with finite element …

Investigation Of Auni5 Films Deposited By Laser Ablation For Rf Mems Switches, Noha Sameh Ahmed Farghal

Archived Theses and Dissertations

No abstract provided.

An Experimental Study Of Single Mode Fiber-Optic Sensors, Joumana Mohamed Taysir El-Rifai

Archived Theses and Dissertations

This thesis is intended to investigate and study various types of single-mode fiber optic sensors. Single-mode fibers will be first defined and understood in order to proceed. We will provide a description of their geometry, the method by which they propagate light and how they can be utilized as sensors. Attention will also be paid to the nature of the optical components used with single-mode fibers, such as: optical sensors and detectors. Since single-mode fiber sensors depend essentially on the interference and the coherence of light, they will also be discussed. Finally, three different single-mode fiber sensor setups will be …

Scattering Of Ultra Wide Band X-Wave Pulses By A Sphere, Maged Fayez Moawad

Archived Theses and Dissertations

No abstract provided.

Suitability Of Egyptian Raw Materials For The Production Of Cement Clinker Using The Dry Process, Lamia Rifaat Ismail

Archived Theses and Dissertations

No abstract provided.

Kinetics Of Oxidation Of Bismuth And Bismuth Based Alloys In Air Between 500 And 530 (Degree) K, Magda Ishak Ahmed Waly El-Guindy

Archived Theses and Dissertations

No abstract provided.

Some Bonding Aspects Of Cobalt Ions In Phosphate Glasses, Tewfik Boutros Absi

Archived Theses and Dissertations

No abstract provided.

Radiation Induced Color Centers In Potassium Silicate Glasses Containing Lead, Ibrahim Abou-Seif Henry

Archived Theses and Dissertations

No abstract provided.

Some A. C. Properties Of Lead-Borate Glasses, Salah El-Din El-Nahwy

Archived Theses and Dissertations

No abstract provided.

Radiation Induced Color Centers In Alkali Silicate Glasses, Ramez Morgan Louca

Archived Theses and Dissertations

No abstract provided.

On The Interaction Of Aluminium And Iron Calcium Borate Glasses And Its Effect On The Properties Of Their Composites, Sherif K. Arif

Archived Theses and Dissertations

No abstract provided.

Interplanar Force Constants Of Symmetry Planes In Close-Packed Structures, Paul G Khoury

Archived Theses and Dissertations

No abstract provided.

On The Physical Properties Associated With Omega Phase In Titanium-Chromium Alloys, Serag El Din El Sayed Habib

Archived Theses and Dissertations

No abstract provided.

L And M Auger Spectra For Silver, Samaa Naga El Ibyari

Archived Theses and Dissertations

No abstract provided.

Analysis Of The Vibrational Modes Of The Triborate Anion, Panayiotis Th. D. Sphicas

Archived Theses and Dissertations

No abstract provided.