Natural & Applied Sciences

Research Papers/Topics in Natural & Applied Sciences

Estimation Of Contralateral Breast Dose For Tangential Breast Irradiation Using Gafchromic Film Ebt2

ABSTRACT The dose to the contralateral breast for tangential breast irradiation has been estimated using Gafchromic films EBT2. The data collected consisted of measurements taken with anthropomorphic female Rando phantom. The EBT2 films were scanned and read using ScanMaker 9800XL plus and ImageJ software. A calibration curve was constructed using fourth – order polynomial fit to the data and a calibration equation was obtained from the graph which was used to convert the grey values ...

Quality Control And Dosimetry Of A Wooden Couch Top For Megavoltage External Beam Radiotherapy.

ABSTRACT  The purpose of this study was to determine an appropriate locally fabricated wood sample that could be used to replace the wire mesh incorporated at the treatment area of EBRT couch top to circumvent dose discrepancies associated with the sagging effect of the wire mesh as a result of prolonged use. Linear attenuation coefficient and transmission factor were determined at three stipulated field sizes (5cm x 5cm, 10cm x 10cm,15cm x 15cm) and two treatment depths of 0.5...

Effect of Drying on Chemical Constituents of Peel Essential Oils of Cleopatra Mandarin (L) Growth in the North Central of Nigeria

ABSTRACT: In this study, the oil extracts from fresh and dried peels of Cleopatra mandarin were isolated and characterized via GC-MS technique. Also the study established both quantitative and qualitative variation in chemical constituents of the essential oils of Cleopatra mandarin (L) cultivated in the North central of Nigeria. Fresh and dried pulverized peels of Cleopatra mandarin (500g) were separately hydro distilled and afforded oil in the range 0.2- 0.8%(w/w) respectively. GC/MS a...

Defining Data Science: Beyond the Study of the Rules of the Natural World as Reflected by Data

INTRODUCTIONData science has received widespread attention in academic and industrial circles. New data science research institutes and organizations have continued to emerge on the scene, such as the Columbia University Institute for Data Sciences and Engineering and New York University Center for Data Science. The University of California at Berkeley, Columbia University, Fudan University, and other universities have launched data science courses and degree programs. Cleveland and Smit...

Distributed Revision Resources (Exam Questions 2019)

Distributed Revision Questions 2019 Preview1.Distinguish  between the link-register model,  and the  message-passing model  in  which  each channel has unit capacity. Then implement the link-register model using the message passing model. 2. A keyboard process K sends an arbitrarily large stream of key-codes to a process P, which is supposed to store them in the memory. In addition to receiving the inputs from K, P also executes an infini...

Development And Evaluation Of The Functional, Nutritional Quality And Consumer Perception And Acceptability Of A Sesame Seed And Peanut Based Complementary Food For Infants 6-24 Months

ABSTRACT Malnutrition among children is still prevalent in most part of Ghana. This is very common in the rural regions of the country where cereal flour is the main source of complementary food for infants. In light of that, legumes such as cowpeas and peanuts are used to enrich the quality of complementary foods to improve child nutrition. Utilization of legumes in complementary feeding come with shortfalls such as the presence of nutritional inhibitors. In this regard, different proc...

Landlocked African Countries and What You Need to Know About Them

A landlocked country is a country that does not have territory connected to an ocean or whose coastlines lie on endorheic basins.  An endorheic basin, also called an internal drainage system, is a drainage basin that normally retains water and allows no outflow to other external bodies of water, such as rivers or oceans, but drainage converges instead into lakes or swamps, permanent or seasonal, that equilibrate through evaporation. Africa is a continent of many countries; 55, to be exac...

Formation of Metastable Calcite-type Barium Carbonate During Low-temperature Decomposition of (Ba,Ti)- Precursor Complexes

Solid State Sciences 9 (2007) 303, doi:10.1016/j.solidstatesciences.2007.02.003, Abstract::(Ba,Ti)-precursor complexes, important for the production of advanced BaTiO3 perovskitetype materials, undergo structural transformations and complex reactions during their thermal decomposition. Based on XRD phase analysis, combined with Rietveld refinement of crystal structure data, and on IR analysis, the intermediate formation of calcite-type BaCO3 is evidenced, which can be explained by the stabili...

Barium Titanate via Thermal Decomposition of Ba,Tiprecursor Complexes: The Nature of the Intermediate Phases

Solid State Sciences 9 (2007) 21, doi:10.1016/j.solidstatesciences.2006.09.004,Abstract::The thermal decomposition of Ba,Ti-precursor complexes, containing organic ligands and suitable for the single-source preparation of nanocrystalline BaTiO3, leads firstly to the segregation of specific Ba-rich and Ti-rich phases. Quantitative electron energy lossspectroscopy and powder X-ray diffraction data indicated that the (i) Ba-rich phase is a BaOstabilised variant of the calcite-type high temperatu...

Semiconducting Properties of Ge-BaSnO3

Journal of Alloys and Compounds 506 (2010) 678–682, doi:10.1016/j.jallcom.2010.07.041,Abstract::The electrical and optical properties of Ge-doped BaSnO3 ceramics sintered at various temperatures have been investigated to determine their semiconductor behavior. The electrical conductivity of Ge-doped BaSnO3 samples increases with increase in temperature, confirming that the samples exhibit a semiconductor behavior. A maximum conductivity value of 6.31 × 10−9 S/cm was observed for the samp...

Thermoanalytical, Optical, and Magnetic Investigations on Nanocrystalline Li0.5Fe2.5O4 and Resulting Ceramics Prepared by a Starch-based Soft-chemistry Synthesis

Journal of Solid State Chemistry 287 (2020) 12138. DOI: 10.1016/j.jssc.2020.121380 Abstract: Nanocrystalline Li0.5Fe2.5O4 was prepared by a starch-based soft-chemistry synthesis. Calcining of the (LiFe)-gel between 350 and 1000 °C results in Li0.5Fe2.5O4 powders with crystallite sizes from 13 to 141 nm and specific surface areas between 35 and 7.1 m2 g-1. XRD investigations reveal the formation of ordered Li0.5Fe2.5O4. Sintering between 1050 and 1250 °C leads to ceramics with relative ...

BaGeO3 as Sintering Additive for BaTiO3-MgFe2O4 Composite Ceramics

RSC Adv., 2015, 5, 71491, DOI: 10.1039/c5ra12312g, Abstract::BaTiO3-MgFe2O4 composites (30 wt.% MgFe2O4) with a small addition of BaGeO3 as a sintering additive were synthesized by a one-pot Pechini-like sol-gel process. Nano-crystalline composite powders with a crystallite size of about 10 nm were obtained after reaction at 700 °C for 1 h. Magnetic investigations suggest that the nano-powder is in its superparamagnetic state at room temperature. The addition of BaGeO3 leads to an improved s...

Effect Of Chronic Exposure To Petroleum Hydrocarbon Pollution On Some Biochemical Parameters Of Individuals Native To Ebocha, Niger Delta

ABSTRACT The impact of pollution due to gas flaring on individuals native to Ebocha in Niger Delta Area was investigated. One hundred and five apparently healthy individuals between 21-70years who consented for the study were screened, seventy five individuals from Ebocha and thirty from Nsukka-a control location with no history of petroleum hydrocarbon pollution. Standard analytical procedures were used in the determination of the concentration of ascorbic acid (AA) of the individu...

Effect of Green Leaf Manuring on Soil Physicochemical and Soil Biological Parameters

ABSTRACT Present study was conducted to evaluate the effect of green leaf manuring on soil physicochemical and biological parameters. Three out of total four soil samples were treated with Mangifera indica, Gmelina arborea and Dialium guineense leaf manures one for each respectively prior to the cultivation of Telfairia occidentalis plant on each of the soil samples including the untreated soil sample (control). Physicochemical and biological parameters of the soil samples, plant gr...

Effect of Mobile Communication Mast on Soil Properties in Lugbe, Federal Capital Teritory, Abuja

ABSTRACT This study examines the effect of GSM mast on soil properties in Lugbe, Municipal Area Council of the F.C.T. The work essentially focuses on the availability or otherwise of heavy metal and its variations along the GSM masts belong to MTN and GLO operation. The soil samples were taken at 20m, 60m and 100m from each of the GLO and MTN masts in order to determine the spatial variation of the heavy metals associated with the mast. The soil samples were analyzed for Ca2+ , Fe2+...


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