Physics Research Papers/Topics

DEVELOPMENT OF A METHODOLOGY FOR ESTIMATION OF LEAF AREA USING THE BETA MASS ABSORPTION COEFFICIENT OF THE LEAF

ABSTRACT Leaf area measurement can be a time consuming process and may require sophisticated electronic instruments. The objective of this research was to develop a simple, and less time consuming method for leaf area (LA) estimation of some leaves of cassava varieties. A method based on the beta mass absorption coefficient of the leaf has been developed and used for the estimation of leaf area of three varieties of cassava and the accuracy and precision of this method has been compared with ...

SYNTHESIS AND CHARACTERIZATION OF CUPRIC OXIDE NANOPARTICLES FOR PHOTOVOLTAIC APPLICATIONS

ABSTRACT A simple inexpensive chemical route has been identified and used to synthesize cupric oxide nanoparticles suitable for photovoltaic applications. X-ray diffraction analysis showed the synthesized nanoparticles to be a pure cupric oxide phase. The particle size and particle size distribution of the cupric oxide nanoparticles were obtained by transmission electron microscopy (TEM) whereas the crystallite size and crystallite size distribution were obtained by X-ray diffraction peak bro...

MEASUREMENT OF ENTRANCE SURFACE DOSE WITH THE FEMALE ANTHROPOMORPHIC PHANTOM ON SELECTED DIAGNOSTIC EXAMINATION USING THERMOLUMINESCENCE DOSIMETRY

ABSTRACT The aim of the study was to measure the entrance surface dose for selected diagnostic Xray examinations using calibrated thermoluminescent dosimeters on an anthropomorphic phantom. Dose measurement obtained with PCXMC software calculations were used to estimate the stochastic radiation risks and age-dependent mortality rates for subsequent assessment of lifetime cancer risk. Entrance surface dose per examination was estimated from X-ray tube output parameters in two digital X-ray uni...

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...

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...

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...

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...

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...

THEORETICAL DETERMINATION OF SOME THERMODYNAMIC PROPERTIES OF SELECTED BINARY LIQUID ALLOYS

ABSTRACT Binary liquid alloys have found wide applications in electronics, communications, automotive and aerospace technologies. The development of new alloys and improvement of existing ones require accurate knowledge of thermodynamic variables of the constituent systems which may not be obtainable experimentally. Hence, there is always the need for theoretical investigation to complement experiment. This study was aimed at theoretical determination of the thermodynamic properties of nine ...

The Study of Acoustic Effects in Carbon Allotropes

ABSTRACT Acoustic effects such as absorption/amplification of acoustic phonons, Acoustoelectric Effect (AE) and Acoustomagnetoelectric Effect (AME) were studied in Carbon Allotropes. In this thesis, the Carbon Allotropes considered are Graphene Nanoribbon (GNR), 2-dimensional Graphene sheet, and Carbon Nanotubes (CNT). The Boltzmann transport equation (BTE) and the phonon kinetic equation (PKE) were used. All results were analysed numerically and graphically presented. Using BTE for Armchair...

DETERMINATION OF STANDARD REFERENCE RENAL VOLUME MODEL AND DOSE OPTIMISATION PROCEDURES FOR CLINICAL APPLICATIONS

ABSTRACT The study is based on measurements of renal dimensions and related body indices to establish standard reference body and renal parameters, renal volume model, renal and effective dose in relation to patients’ dose optimization procedures. The materials used include: MDCT Machine, Weighing scale, BMI calculator and MVL workstation. Technical parameters were obtained from three groups of randomly selected patients undergoing abdominal CT examinations including: 175 patients of age 20...

WEST AFRICAN MONSOON (WAM) JUMP AND ITS IMPLICATION FOR RAIN-FED AGRICULTURE IN THE TRANSITION AND COASTAL SAVANNAH AGRO-ECOLOGICAL ZONES OF GHANA

ABSTRACT West African rainfall variability plays an essential role in the economies of West African countries it has a major influence on industrial and agricultural production, which is largely, weather dependent. This plays an important role in food security and water availability. This work focuses on the West African Monsoon (WAM) jump and its implication for rain-fed agriculture in the Transition and Coastal Savannah agro-ecological zones of Ghana. In this study, the seasonal rainfall va...


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