IOSR-JAP   Volume-11 ~ Issue-2 ~ March-April 2019

ABSTRACT: Radio refractivity over Awka, South Eastern Nigeria has been studied using meteorological parameters on the troposphere during dry and wet seasons, from 2013 – 2014 respectively. Wireless weather stations (Integrated Sensor Suite, ISS) were positioned at five different height levels beginning from the ground surface and at intervals of 50 m from the ground to a height of 200 m (0, 50, 100, 150 and 200 m). The data used for the computation of radio refractivity and refractivity gradient is a 30 minutes interval variation of metrological parameters for each day in the troposphere over Awka. Hourly, daily and monthly averages of radio refractivity during dry and wet seasons were calculated from the data obtained. The result indicated that the radio refractivity during wet season...........

Keywords – Radio Refractivity, Refractivity Gradient, sub-refractivity, super-refractivity and Troposphere

[1]. Serdega, D., Ivanovs, G., (2007). Refraction seasonal variation and that influence on to GHz range microwavesavailability. Electronics and Electrical Engineering 6 (78), 39–42.
[2]. Caglar, Y., Peter, G., & William, S.H., (2006). Estimation of radio refractivity from radar clutter using Bayesian Monte Carlo analysis. IEEE Transactions on Antennas and Propagation 54 (4), 1318 1327.
[3]. Naveen, K.C., Trivedi, D.K., Roopam, G., (2010). The impact of K-factor on wireless link in Indian semi desert terrain. International Journal of Advanced Networking and Applications 02 (4), 776–779.
[4]. Maitham, A., & Asrar, V.H.S., (2003). Signal strength measurement at VHF in the eastern region of Saudi Arabia. Arabian Journal for Science and Engineering 28 (2C), 3–18.
[5]. Freeman, R.L., (2007). Radio System Design for Telecommunications, 3rd ed. Wiley Interscience, New York.

ABSTRACT: This study was carried out to evaluate dosimetric differences between Intensity Modulated Radiotherapy (IMRT) delivery techniques (which can be divided into two deliverymodes: Step-and-Shoot (SS)&Sliding Window (SW)) and Three-dimensional Conformal Radiotherapy (3D-CRT).Twenty prostate cancer patients on Eclipse treatment planning system for delivery on a Varian DMX linear accelerator with Multileaf Collimator MLC (Millennium 80-leaf MLC) with 6 MV photon beams were generated using both IMRT & 3D-CRT techniques. Patients had two planning target volumes (PTVs) which were prostate plus seminal vesicles (PTV1) for the primary.........

Keywords: Intensity modulated radiotherapy, prostate cancer, sliding window, step-and-shoot, three-dimensional conformal radiotherapy

[1]. C.E. Oh, K Antes, M. Darby, S. Song, and G.Starkschall,Comparison of 2D conventional, 3D conformal, and intensity-modulated treatment planning techniques for patients with prostate cancer with regard to target-dose homogeneity and dose to critical, uninvolved structures, Medical Dosimetry, 24(4),1999, 255-263.

[2]. G. Luxton, S.L. Hancock, and A.L. Boyer,Dosimetry and radiobiologic model comparison of IMRT and 3D conformal radiotherapy in treatment of carcinoma of the prostate, International Journal of Radiation Oncology* Biology* Physics, 59(1), 2004, 267-284.

[3]. M.J.Zelefsky, Z.Fuks, L.Happersett, H.J. Lee, C.C.Ling, C.M.Burman, M. Hunt, T. Wolfe, E.S. Venkatraman, A. Jackson, and M.Skwarchuk,Clinical experience with intensity modulated radiation therapy (IMRT) in prostate cancer, Radiotherapy and Oncology, 55(3), 2000, 241-249.

[4]. M. Skala, L. Holloway, M. Bailey, andA.Kneebone,Australia‐wide comparison of intensity modulated radiation therapy prostate plans, Australasian radiology, 49(3), 2005, 222-229.

[5]. A.Pirzkall, M.P. Carol, B. Pickett, P. Xia, M. Roach III, andL.J.Verhey,The effect of beam energy and number of fields on photon-based IMRT for deep-seated targets, International Journal of Radiation Oncology* Biology* Physics, 53(2), 2002, 434-442.

ABSTRACT: Global solar radiation changes and climatic variation are the most of the world's environmental problems. Solar radiation received at the earth's surface under different atmospheric conditions obviously affect the amount and quality of radiation obtained at the ground during the course of the day. The variation in climatic parameters like pressure,temperature,rainfall,humidity,wind, precipitation, turbidity, transparency and distribution of cloud cover have been suggested to exert depleting influence on solar radiation data. This paper is focused on the development of graphical polygon method based on the extraterrestrial and terrestrialsolar irradiation amount and the interpretation concerning the clearness index of Lagos south west part of Nigeria with solar irradiation measurement.........

Keywords: Radiation, extraterrestrial, terrestrial, clearness index

[1]. Falayi, E. O., Rabiu, A. B and Teliat, R. O. (2011). Correlations to estimate monthly mean of daily diffuse solar radiation in some selected cities in Nigeria. Advances in Applied Science Research, 2 (4): 480-490. Pelagia Research Library.
[2]. Che, H.Z, Shi, G. Y, Zhao, J.Q, and Li, Y (2007). Analysis of sky condition using 40 years records of solar radiation data in China. Theoretical and applied climatology. 89: 83-94.
[3]. Bocco, M., Enrique, W. and Monica, A. (2010) Comparison of regression and neural networks models to estimate solar radiation. Chilean Journal of Agriculture Research; 70(3):428-435.
[4]. Angstrom, A.S (1924). Solar and terrestrial radiation. Meteorological Society 50: 121 -126.
[5]. Prescott, J.A. (1940). Evaporation from a water surface in relation to solar radiation. Tran. R. Soc. S. Austr. 114-118..

ABSTRACT: This paper was carried out to studythe efficiency of Monitor Units (MUs) between Intensity Modulated Radiation Therapy (IMRT)Step-and-Shoot(SS) and Sliding Window(SW) modes.Fifty-onepatients with localized prostate carcinoma wereplannedby optimization process of treatment planning system. Patients had two planning target volumes (PTVs) for the primary and boost plans. Target coverage was evaluated with parameters of the mean target dose (Dmean), the maximum target dose (Dmax), while its dose distribution and conformality was evaluated with several different indices such as Conformity Index (CI), the Homogeneity Index (HI), quality of coverage, Lesion Coverage Factor (LCF),Uniformity Index (UI), and Conformation.........

Keywords: Intensity Modulated Radiation Therapy, Monitor Units, Sliding Window, Step-and-Shoot,Prostate Cancer.

[1]. Intensity Modulated Radiation Therapy Collaborative Working Group,"Intensity-modulated radiotherapy: current status and issues of interest",International Journal of Radiation Oncology* Biology* Physics, 51(4):880-914, 2001.
[2]. P. Hoban, "Investigations Into Static Multileaf Collimator Based Intensity Modulated Radiotherapy", (Doctoral dissertation, University of NewSouth Wales), 2004.
[3]. R. Mohan, M. Arnfield, S. Tong, Q. Wu,"The impact of fluctuations in intensity patterns on the number of monitor units and the qualityand accuracy of intensity modulated radiotherapy",Medical physics, 27(6):1226-1237, 2000.
[4]. D.P. Dearnaley, M.R. Sydes, J.D. Graham, E.G.Aird, D. Bottomley, R.A. Cowan, R.A. Huddart, C.C. Jose, J.H. Matthews, J. Millar, A.R. Moore, "Escalated-dose versus standard-dose conformal radiotherapy in prostate cancer: first results from the MRC RT01 randomised controlled trial", The lancet oncology, 8(6):475-487, 2007.
[5]. E.J. Hall,"Intensity-modulated radiation therapy, protons and the risk of second cancers",International Journal of Radiation Oncology* Biology* Physics, 65(1): 1-7, 2006..

ABSTRACT: Fluctuations of a current in spending environments arise at availability external influences. It can take place, if the spending environment is in an external electric floor, in external electric and magnetic fields and even at availability of a gradient of temperature in the environment. In semiconductors (electronic type, electronically-hole type) carriers of a charge from external influences are accelerated or slowed down impurity by the centers and consequently distribution of a charge in the semiconductor deviates equilibrium values and thus inside of the semiconductor there are areas with different values of an electric field. These sites (them name domains) move on all image and then there are fluctuations of a current in-external a circuit [2]. In impurity semiconductors recombination...........

[1]. Nonlinear Oscillations of the Charge Curriers Concentration and Electric Fieldin Semiconductors With Deep Traps. F.F. Aliyev, E.R. Hasanov,10SR Journal of applied Physics (10SR-JAP) e-ISSN. 2278-4861. Volume 10. ISUE 1. Yer. II (Jan-Feb 2018) PP 36-42.
[2]. Электрические домены в полупроводниках с горячили электронами В.Л. Бонч-Бруевич ФТТ. Т. 2. 1986. стр.356.
[3]. Доменная электрическая неустойчивость в полупроводниках. В.Л. Бонч-Бруевич., И.П. Звягин А.Г. Миронов издательство «Наука» Москва 1972. стр.34-36.
[4]. Non-linear electric and magnetic fieldof radiation E.R. Hasanov. R.K. Mustafayeva., A.R. Salimi., S.S. Ahadova., K.N. Yusifova 13th international Conference on «Technical and Physical Problems of Electrical Engineering». 21-22 September 2017. Pages 201-204.
[5]. Internal and external instability in low- dimensional conducting medias, E.R.Hasanov, R.K.Mustafayeva, IOSR Journal of applied Physics (IOSR-JAP) e-ISSN. 2278-4861. Volume 11. ISSUE 1. Ser. II (Jan-Feb 2019) PP 08-12.

ABSTRACT: The nanoparticles of Gd doped Ni0.5Co0.5Fe2O4 for composition of Ni0.5Co0.5GdyFe2-yO4 (y=0.025) synthesized by sol-gel auto combustion technique using citric acid as a fuel. The structural and morphological characterizations were carried out by X-ray diffraction technique. The particle size obtained by FWHM of (311) plane using Scherrer's formula obtained to be 31 nm. Magnetic properties were investigated using Vibrating sample magnetometer (VSM) technique. The saturation magnetization values show the ferromagnetic nature. The structural and magnetic parameters are in the reported range.

Keywords: Ferrite, magnetic properties, nanoparticles.

[1]. Amiri S, Shokrollahi H. Materials Science and Engineering: C 2013;33:1-8.
[2]. Hu W, Qin N, Wu G, Lin Y, Li S, Bao D. Journal of the American Chemical Society 2012;134:14658-61.
[3]. Bhujun B, Tan MT, Shanmugam AS. Results in physics 2017;7:345-53.
[4]. Gul I, Abbasi A, Amin F, Anis-ur-Rehman M, Maqsood A. Journal of magnetism and magnetic materials 2007;311:494-9.
[5]. Srivastava M, Chaubey S, Ojha AK. Materials Chemistry and Physics 2009;118:174-80..

ABSTRACT: The nanocrystalline Barium Strontium Titanate (BST) powders were synthesized by mechanochemical method using barium carbonate (BaCO3), titanium dioxide (TiO2) and strontium carbonate (SrCO3) as the precursors. Conventional ball-milling also preferred to get average particle size. The powder was sintered at 6000C, 7500C and 8000C. X-ray Diffraction (XRD) technique was used to know structural properties of BST powder and EDAX is used for quantitative elemental analysis. The decomposition and crystalline behavior of BST were examined by Thermogravimetric..........

Keywords: Mechanochemical synthesis, sintering, BST nanopowder, Particle size, XRD

[1]. B. Hou, Y. Xu, D. Wu, and Y. Sun, "Preparation and characterization of single-crystalline barium strontium titanate nanocubes via solvothermal method," Powder Technology, vol. 170, no. 1,pp. 26–30, 2006.
[2]. F.M. Pontes, E. Longo, E. R. Leite et al., "Photoluminescence at room temperature in amorphous SrTiO3 thin films obtained by chemical solution deposition, "Materials Chemistry and Physics, vol. 77, no. 2, pp. 598–602, 2003.
[3]. F. M. Pontes, C. D. Pinheiro, E. Longo et al., "Theoretical and experimental study on the photoluminescence in BaTiO3amorphous thin films prepared by the chemical route," Journal of Luminescence, vol. 104, no. 3, pp. 175–185, 2003.
[4]. S. Otsuka-Yao-Matsuo, T. Omata, S. Ueno, and M. Kita, "Photo bleaching of methylene blue aqueous solution sensitized by composite powders of titanium oxide with SrTiO3, BaTiO3, and CaTiO3," Materials Transactions, vol. 44, no. 10, pp. 2124–2129, 2003.
[5]. T. Tsumura, K. Sogabe, and M. Toyoda, "Preparation of SrTiO3-supported TiO2 photocatalyst," Materials Science and Engineering B, vol. 157, no. 1–3, pp. 113–115, 2009.

ABSTRACT: Foodstuff pollution is a major concern now-a-days, especially in Bangladesh. Toxicity assessment of baby food is essential before providingto the children. The quantitative estimation of trace and major elements, their concentrationof ten different milkpowdersamples collected from local markethas been done. The total experimental works from sample preparation to spectrum data analysis have been done at the Accelerator Laboratory of Atomic Energy Center, Dhaka.The IBA technique PIXE and spectrum analysis shows that the major elements found in all the ten samples are S..........

Keywords: PIXE, toxicity, IBA,GUPIX, MAESTRO-32

[1]. Eric J. Underwood, Dept. Of Animal Science and Production, University of Western Australia, "TraceElements in Human and Animal Nutrition" Fourth Edition (1977).
[2]. M. Govil, Proton Induced X-ray Emission – A tool fornon-destructive trace element analysis, Current Science,80(12), 2001, 1542-1549.
[3]. Md. Joynal Abedin, Shirin Akter, SK. Abdul Kader Arafin, "Chromium Toxicity in Soil around Tannery inHazaribagh, Dhaka, Bangladesh and its Impacts on Environment as wellas Human Health" International Journalof Innovative Research in Advanced Engineering (IJIRAE) ISSN: 2349-2163, issue 4, volume 2 (April 2015), pp,119-122, w.w.w.ijirae.com.

ABSTRACT: The spring was studied and proven to be a simple machine. This is an addition to the six simple machines. The two concepts of the spring were compression and tension. The applicationsof the string ranged from protecting objects to creating a stored force. Examples of the springs were given.It may also serve as an inductor, a prime requirement of motors and generators

Keywords: Ductility Malleability Melting point Mechanics Spring Strength of materials

[1]. Asimov, Isaac (1988). Understanding Physics, New York, New York, USA: Barnes & Noble, p. 88.

[2]. Anonymous (2018a). Spring from https://www.merriam-webster.com/dictionary/spring

[3]. Anonymous (2018b). How are Sring made? fromhttps://www.thomasnet.com/articles/machinery-tools-supplies/how-are-springs-made
[4]. Anonymous (2018c).machine from https://www.britannica.com/technology/machine
[5]. Anonymous (2018d).spring and their types from http://ispatguru.com/springs-and-their-types/

ABSTRACT: In this paper, the stability theorem, the strict stability theorem, the independence theorem, and the uniqueness theorem of nature are proposed, and the principle of data regulation of human nervous system is expounded. And this operating principle exists only. Relevant research will be advanced.

[1]. Zhe Yin, 2016. Zhe Yin's energy and wave theorem. International Journal of Engineering and Advanced Research Technology, 2(3), 44-45.
[2]. Zhe Yin, 2017. The function and relation of proton and neutron. International Journal of Recent Scientific Research,8(1), 15321-15324.
[3]. Zhe Yin, 2017. Effect of Gravitational Wave on DNA Base. International Journal of Recent Scientific Research, 8(2), 15705-15707.
[4]. Zhe Yin, 2017. The formation of elements. IOSR Journal of Applied Physics,9(2), 08-13.
[5]. Zhe Yin, Liu, D., 2016. Electron trajectory. International Journal of Applied Science and Mathematics,3( 2), 56-57.

ABSTRACT: Schrödinger Equation for spherical atoms and nano particles was used to describe the behavior of electrons and phonons by treating them as strings oscillating thermally and under the action of external force. The solution shows that for thermally excited phonons and electrons the energy and frequency are quantized .For electrons excited by external force the energy and frequency are also quantized. The energy in both cases resembles the zero point energy for harmonic oscillator of the quantum system. The solution also describes free as well as bounded electrons. The results obtained agree with previous models and observations.

Keywords: Schrödinger Equation, spherical symmetry, string theory, phonon, energy quantization

[1]. David. J. Griffith, Introduction to Quantum Mechanics (Prentice Hall, New Jerssy, 2005).
[2]. L. I. Schiff, Quantum Mechanics (McGraw Hill, Tokyo, 2009).
[3]. Schawbl, F, Quantum Mechanics, 3rd Edition (springer, Berlin, 2005).
[4]. Dyson, F. J, Advanced Quantum Mechanics, 2nd Edition (world Scientific, Singapore, 2006).
[5]. R. P. Feynman and A. R. Hibbs, Quantum Mechanics and Path Integrals (McGraw Hill, Inc, New York, 1965).

ABSTRACT: Schrodinger equation was used for nano particles are considered as spherical crystals that are uniformly distributed. The solution shows that the wave function predicts uniform distribution of particles which conform to the assumptions. Applying periodic conditions the energy is shown to be quantized when thermal force exceeds the. External vibrating force opposing it.Unlike ordinary models the energy decreases as the quantum number increases.

Keywords: spherical symmetry, Schrödinger Equation, nano particles, crystals, energy, quantization

[1]. David. J. Griffith, Introduction to Quantum Mechanics (Prentice Hall, New Jerssy, 2005).
[2]. L. I. Schiff, Quantum Mechanics (McGraw Hill, Tokyo, 2009).
[3]. Schawbl, F, Quantum Mechanics, 3rd Edition (springer, Berlin, 2005).
[4]. Dyson, F. J, Advanced Quantum Mechanics, 2nd Edition (world Scientific, Singapore, 2006).
[5]. R. P. Feynman and A. R. Hibbs, Quantum Mechanics and Path Integrals (McGraw Hill, Inc, New York, 1965).

ABSTRACT: Cu2ZnSnS4 (CZTS), made entirely of abundant materials, has attracted a great interest due to its potential applications in sustainable thin-film solar cell devices. The electronic band structure of kesterite Cu2ZnSnS4 compound has been calculated using the pseudo-potential method. Projector augmented waves (PAW) within the density functional theory (DFT) was used in all calculations using local density approximation (LDA) for one calculation and inclusion of potential correlation term, U to LDA (i.e LDA + U) in another calculation. The results predicted Cu2ZnSnS4 to be a p-type semiconductor with bandgap value for (1) LDA as 0.039 eV and (2) LDA + U as............

Keywords: Cu2ZnSnS4, band structure, band gap, density of states.

[1]. Babichuk I. S., Yukhymchuk V. O., Dzhagan V. M., Valakh M. Y., Leon M., Yanchuk I. B., Gule E. G. and Greshchuk O. M. (2013). Thin films of CU2ZnSnS4 for solar cells: Optical and structural properties. Functional materials 20(2), 186-191.
[2]. Shraavya R, Ankita M., Himani V and Prerna G. (2016). Emerging photovoltaics: Organic Copper Zinc TinSulphide and Perovskite–Based Solar Cells.Journal of Applied Chemistry,8(3),1-12.
[3]. Green M.A., Emery K., Hishikawa Y. and Warta W. (2010). Solar cell efficiency tables.Progress in photovoltaics research and applications, 18(35), S:144-150.
[4]. 4 Ramasamy K., Malik M.A. and O'Berin P. (2012). Routes to Copper Zinc Tin Sulphide (Cu2ZnSnS4), a potential material for solar cells. Chemical Communications 10, 1039-1051.
[5]. Anuar K., Tan W.T., Atan M.S., Dzulkefly K., Ho S.M., JelasH.Md and Saravanan N. (2007). Cyclic Voltammetry study of coppr tin sulfide compounds. Pacific Journal of Science and Technology. 8(2): 252 -260..