Physics Research Papers/Topics

Determination Of The Mechanical Properties Of A Biodegradable Thermoplastic – Polylactic Acid And Comparison With Those Of Polyethylene

ABSTRACT Polyethylene (PE) bags have become the most widely used plastic commodity due to the fact that they are light and have good barrier properties against water and water – borne organisms. The energy requirements for their production as compared to other materials are much lower and the effluents emitted during manufacture of PE compared to paper bags (from trees) are much lower. They are however non-biodegradable and hence are one of the top environmental pollutants. Environment fri...

Cosmic Rays Variability In The Mid And High Latitudes During Solar Quiet Days

ABSTRACT We have studied the variability of Cosmic rays flux during solar quiet days at mid and high latitudes. By using the five (5) quietest days for each month, the monthly mean diurnal variation of cosmic ray anisotropy have been derived for the period 1981-2007, which covers part of cycles 21, 22 and 23. These quiet days are days during which the sun is relatively magnetically quiet, leading to less anisotropic behavior in the diurnal flux of cosmic rays measured on the earth’s surfac...

Formaldehyde Observations towards Methanol Maser Sources

Abstract Observational works on 4.83 GHz Formaldehyde (H2CO) absorptions and 4.87 GHz H110α radio recombination lines towards 6.7 GHz Methanol (CH3OH) maser sources are presented. Methanol masers provide ideal sites to probe the earliest stages of massive star formation, while 4.8 GHz Formaldehyde absorptions are accurate probes of physical conditions in dense and low temperature molecular clouds towards massive star forming regions. Feature similarities between the formaldehyde absorptions...

Investigation Of Usable Thermoelectric Voltage Generated By Computer Waste Heat

ABSTRACT Computers use electric current to process information. Heat is generated in computer components whenever current flows through it, the heat generation causes unavoidable heat build up and a subsequent temperature rise at and around the components. High operating temperature is dangerous to the safety and reliability of components since the failure rate of computer components increases almost exponentially with the increase in operating temperatures. Similarly, the heat generation lea...

Galactic Cosmic Ray Variability In The High And Mid Latitudes During Solar Cycles 22 And 23

ABSTRACT Galactic cosmic rays are modulated in the hliosphere primarily due to the global merged interaction regions with intense magnetic field which leads to a decrease in the galactic cosmic rays throughout the heliosphere. Using long term averages of solar wind (SW) component parameters in addition to cosmic ray count rates of two high latitude Neutron monitor stations (Apatity and Thule) and two mid latitude stations (Newark and Tbilisi) with different rigidity cut-offs, we analyzed the...

A Review of Climate Changes Due to The Global Worming

In this research we studied the global warming by knowing the definition, and the causes. This research covers the Earth's atmosphere in details and the gases in each layer. Also the physical properties (pressure, thickness, temperature, speed of sound, density, mass), optical properties (scattering, absorption, emission, refractive index). Other aspects such as the Industrial Revolution and its role in the increase of greenhouse gases, the study covers United States of America, and Chi...

Study of Stoke and Amplified Spontaneous Emission Properties of some Diamino Phenyl Propen Derivatives

This study comprises the synthesis and spectral properties of three chalcones 3-(4-n (dimethylamino)phenyl)-1-phenyl-(2E)-propen-1-one (DMAPPP),1-(4-methylphenyl)- 3-(4- N, N-dimethyl amino phenyl)-2-propen-1-one (MDMAPP) and 1-(4- chloridephenyl)-3-(4- N, N dimethyl amino phenyl)-2-propen-1-one (CPDAPP) in several organic solvents have been studied. Photophysical characteristics such as absorption, fluorescence spectra, stokes' shift, fluorescence and quantum yield of these chalcones w...

Characterization Of Zn/Au Back Contact To Lowdoped P-Inp

Abstract. The mechanism behind the formation of alloyed ohmic contacts to p-type InP doped in the 1016 cm-3 range has been investigated. Techniques used for - characterising the contacts include the scanning electron microscope (SEM), specific contact resistance measurements, x-ray diffractometry (XRD), energy dispersive x-ray analysis (EDAX) and Auger electron spectroscopy (AES). Both temperature and time of annealing were varied during the study. The results obtained using our annealing pr...

Preparation of an Emulsifier by Gum Arabic Solution and Black Cumin Seed Oil and Studying Its Optical Properties

The importance of this research comes from made a new material (Emulsion Definition) by used Gum Arabic and Black seed oil. The aim of this Research is Determine The optical properties of (Emulsion Definition) that made by used Gum Arabic Solution and black seed oil Such as (absorbance, transmission, reflection, absorption coefficient, extinction coefficient, refractive index and optical energy band gap) and to compare the result with pure gum Arabic solution result. In this research F...

The effects of Cs-137 gamma photons on the electrical characteristics of Silicon diode 1N4007

In this thesis, experimental measurements were carried out to determine the radiation induced effect on the electrical properties of silicon based diode type 1N4007. The gamma ray photons of Cs-137 source were used to irradiate the diode under test. The results in terms of IV characteristics were compared for post and pre irradiated diode. It is found that the forward current has increased with respect to operating voltage (0.7V) by about 42%. Furthermore, the possibility of using cemen...

Synthesis And Characterization Of Some Core-Shell Oxide Materials

ABSTRACT Core-shell oxide thin films of TiO2/MnO, TiO2/CoO, TiO2/NiO and TiO2/CuO have been successfully synthesized and deposited on glass substrates, using the chemical bath deposition [CDB] technique. To ensure uniform coating, surface pre-treatment was carried out by cleaning slides with detergent, deionised water, ammonia acid and rinsed with acetones. The core of the films was synthesized from TiCl3, NaOH and PVA while the shells were synthesized from MnCl2.4H2O, CoCl2.6H2O, NiSO4 and ...

Analysis Of The Geothermal Potential Of The North West Olkaria Prospect (Oserian Sanctuary) In Kenya, Using Transient Electromagnetic Method And Magnetotelluric Method

ABSTRACT The Northwest Olkaria prospect, Oserian Sanctuary, is part of the Greater Olkaria Geothermal Area located within the Kenyan rift valley in Nakuru County. It is bounded by the longitudes 360 15′E and 360 12′E with an estimated area of 30 km2. Studies previously done did not adequately cover the area to the North West hence no geophysical data is available on the resistivity of key concealed geothermal structural features like thin massive heat sources and shallow faults based on s...

Effect Of Ultraviolet-A And Ultraviolet-C Light On The Concentration Of Vitamin D2 And Mechanical Properties Of Oyster Mushrooms During Growth

ABSTRACT The sun emits ultraviolet radiation in the form of ultraviolet-A (UV-A), ultraviolet-B (UV-B), and ultraviolet-C (UV-C) bands. Ultraviolet light has the potential to boost vitamin D2 production in mushrooms which are the only non-animal food source of vitamin D for humans. The ergosterol in mushrooms, a component of fungal cell membranes which serves the same function as cholesterol in animal cells, can be converted into vitamin D2 by exposure to controlled UV light. However, mushroo...

Tri-linear Soft Couplings Running in Five Dimensional Minimal Super-symmetry Standard Models

In this dissertation, we derived the Renormalization Group Equations (RGEs) for five dimensional Minimal Super-symmetric Standard Model (MSSM) plus additional fields . We found a successful unification of gauge coupling constants in this model very close to: GeV. Yukawa couplings seemed to be tending to unify at some high scale and approximately vanish beyond the unification scale of the gauge couplings, i.e. GeV. We showed that a five dimensional (5D) MSSM with compactification scale o...


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