Physics Research Papers/Topics

IN VIVO TRANSIT DOSIMETRY WITH ELECTRONIC PORTAL IMAGING DEVICES (EPID) FOR EXTERNAL BEAM CANCER TREATMENTS

ABSTRACT According to the Radiotherapy Risk Profile report by the World Health Organization (WHO), the major causes of severe radiotherapy incidents are due to human errors. The real danger is when the error in administration goes undetected during cancer treatments. This may lead to radiation damage to normal tissues, and may be lethal to the patient. The aim of this work was to develop a transit dosimetry calculation model using C++ and vb.net codes for verifying patient radiation doses us...

Variability of permeability with diameter of conduit

Abstract An entry length is always observed before laminar flow is achieved in fluid flowing in a conduit. This depends on the Reynolds number of the flow and the degree of smoothness of the conduit. This work examined this region and the point where laminar flow commences in the context of flow through conduit packed with porous material like beads, of known porosity. Using some theoretical assumptions, it is demonstrated that permeability varies from zero at wall–fluid boundary to maximu...

STUDY OF PERMEABILITY OF SATURATED HOMOGENEOUS AND HETEROGENEOUS POROUS MEDIA

ABSTRACT Many practical seepage and drainage problems can be studied by constructing flow nets for section with a single permeability, however many natural soil deposits are more or less stratified often with horizontal bedding that make horizontal permeability much greater than the vertical.

Lead Adsorption in Clay and Its Application

ABSTRACT This work presents the adsorption capacities of some heavy metals in clay soil and its application in medical field. Nitrate of lead solution of different concentrations were prepared (400ppm, 800ppm… 6400ppm). Each concentration of lead nitrate solutions was mixed with a known volume of clay. Slabs of regular dimensions were formed from the residue after it had gone through filtration. Each slab (dried) was irradiated with x-ray radiation at different energies; 40kev, 60kev, 80kev...

EFFECTS OF CO2 AND CH4 EMISSIONS ON CLIMATE VARIABILITY IN THE TROPICS

ABSTRACT Climate variability is indicated as anomalies in weather parameters such as rainfall and temperature. These are being influenced by greenhouse gas emissions such as carbon dioxide (CO2) and methane (CH4), amongst others. This variability is usually studied using General Circulation Models (GCMs) and empirical models obtained from analyses of data at synoptic weather stations. The GCMs give different predictions from model to model due to parameterisations of microprocesses embedded ...

OPTIMIZATION OF RADIOLOGICAL PROTECTION OF PATIENTS UNDERGOING MAMMOGRAPHY EXAMINATION IN GHANA

ABSTRACT Quality control tests have been undertaken on thirteen mammography systems with the aim of optimizing procedures and patient radiation protection, establishing diagnostic reference levels (DRLs) and establishing quality control (QC) baseline data for the diagnostic mammography practice in Ghana. Quantitative image quality analysis was performed with “ImageJ” software using the “Rose Model” while all other tests were performed using internationally accepted protocols. Results...

DIODE LASER SPECTROSCOPIC STUDIES OF BIOLOGICAL MATERIALS USING ABSORPTION AND EMISSION TECHNIQUES

ABSTRACT Two diode lasers with optical spectroscopic properties for absorption and emission spectroscopy have been used as sources in the study of economically important biological materials. In the emission spectroscopy a fluorosensor with a diode lasing at 396 nm was used to conduct in-vivo and invitro water-stressed study on the leaves of male and female plants by recording their chlorophyll fluorescence induction kinetics at the red and far-red bands as well as their ratios. Using the c...

A Case Study of the Depth of Fresh/Salt Water Interface Using Values of Freshwater Heads in Groundwater of Variable Density

ABSTRACT Almost two thirds of the world's population lives within 400 km of the ocean shoreline; just over half live within 200 km, an area only taking up 10% of the earth's surface. As the world's population continues to grow at an alarming rate, fresh water supplies are constantly being depleted, bringing with it issues such as saltwater intrusion and increasing the importance of groundwater monitoring, management, and conservation. Constant monitoring of the fresh/salt water interface is n...

Occupational Exposure due to RF leakages within GSM Base Station Cabins in Eastern Nigeria

ABSTRACT The occupational exposure due to RF radiation leaks inside the base station cabin, when working on the Base station Transceiver (BTS) Radios and TX cables and during active radio communication was measured. A total of number 30 base stations Cabins were studied in the eastern part of Nigeria, using a Broad band TES-90 Electrosmog meter. The maximum instantaneous electric field strength obtained from GSM 1800 radio was 3.72 V/m, 16.56 V/m for GSM 900 radio and 11.29 V/m for the Tx ca...

ENERGY-ECONOMIC ANALYSIS OF POWER PLANT CARBON DIOXIDE CAPTURE AND PIPELINE TRANSPORT IN TEXAS GULF COAST

ABSTRACT The total investment cost of a pipeline network to transport carbon dioxide (CO2) from power plants for enhanced-oil-recovery (EOR) in oil fields in Texas Gulf Coast as CO2 mitigation has been estimated. The impact of the CO2 capture and transport on power generation cost, including the benefits of atmospheric CO2 mitigation has also been determined. 14 power plants comprising 55.7% of installed capacity in Texas Gulf Coast were selected. Geographical-informationsystem was used to op...

The impact of the variability of ionospheric phase refractive index on radio signals instability

ABSTRACT The ionospheric phase refractive index is a complex function that determines the attenuation and the trajectory of radio signals through the ionosphere. This complex refractive index model has been obtained using the Maxwell's equations, the tensorial conductivity equation, electron collision models, and the geomagnetic field model. The model has been used to study and investigate the phase refractive index on radio wave propagation for high latitude, low latitude and equatorial regi...

FABRICATION AND CHARACTERISATION OF SUPERSTRATE COPPER ZINC TIN SULPHIDE (Cu2ZnSnS4) THIN FILMS SOLAR CELLS

ABSTRACT Greenhouse gases emitted from burnt fossil fuels are major contributors to global warming which currently threatens existence of life. Hence, the global campaign for the replacement of fossil fuels with solar energy. The Cu2ZnSnS4 (CZTS) thin film has emerged as a promising material for photovoltaic absorption layer in the fabrication of solar cells. Various methods of deposition have been used to fabricate superstrate CZTS thin film solar cells. However, there is limited informatio...

Radiological Analysis of 40K, 226Ra and 232Th in Fish, Crustacean and Sediment Samples from Fresh and Marine Water in Oil Exploration Area of Ondo State, Nigeria

ABSTRACT Radiological analysis was carried out on fish, crustacean and sediment samples collected from both fresh and marine water of river Igbokoda in the coastal area of Ondo State, Nigeria. The activity concentrations of radionuclides were determined using gamma spectrometry method. The means of the annual effective ingestion dose varied between 23.3 ± 10.2μSv.y-1 (OreochromisniloticusandGymnarchusniloticus) and 34.8 ± 1.7 μSv.y-1 (Parachnnaobscura) for fresh water fish samples and 6....

CHARACTERIZATION OF CATARACTOUS LENSES OF SPRAGUE – DAWLEY RATS USING SELECTED OPTICAL SPECTROSCOPIC TECHNIQUES

ABSTRACT Current methods for discriminating cataractous lenses from healthy lenses during preclinical studies are based on either histopathological or clinical assessments which are weakened by subjectivity. In this work, four optical spectroscopic techniques: slit lamp microscopy, multispectral imaging (MSI), Laser-induced auto fluorescence (LIAF) and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy have been used to study and characterize cataractous as well a...

OPTICAL STUDIES AND CHARACTERIZATION OF PLASMODIUM FALCIPARUM INFECTED HUMAN RED BLOOD CELLS

ABSTRACT In this work, three optical techniques: spectral imaging, laser-induced fluorescence (LIF) and spectrophotometry were used to study and characterize uninfected red blood cells (RBCs) (u-RBCs) and P.falciparum infected RBCs (i-RBCs). Unstained blood smear slides were prepared from blood samples of volunteers who were tested positive for P.falciparum infections (i-blood) and after treatment (u-blood). Optical characteristics of the i-RBCs in spectral images, captured in reflection, sca...


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