IOSR-JAP   Volume-3 ~ Issue-5 ~ March–April 2013

Abstract: Mixed crystals of alkali halides find their applications in optical, opto-electronics and electronic devices. In the present study the pure and ZnS added mixed crystals 𝑁𝑎𝑥 𝐾1−𝑥 𝐶𝑙 were grown from the aqueous solution. The grown crystals were characterized by taking XRD, TG / DTA and Vicker's micro hardness measurement. The Debye temperature is an important parameter of a solid. Several methods of evaluating Debye temperature are available. In the present study Debye temperatures were calculated from the Debye-waller factor, melting point and microhardness. The results were compared with the Kopp Neumann relation.

Key words : Mixed crystals, Alkali halides, Debye temperature, Debye frequency

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Abstract: Nanocrystalline of titanium dioxide nano films were deposited by spin coating method on silicon and ITO-glass substrates at 2000 rpm, in which starting material of Titanium Isopropoxide (C12H28O4Ti).X-ray diffraction (XRD) patterns confirmed thatpolycrystalline TiO2 anatase phase formation. The intensity of XRD peaks increases with the increase in heat treatment and better crystallinity takes place at higher temperature. The morphology of deposited films were characterized by atomic force microscope (AFM); with increasing heat treatment, both the particle size and surface roughness increased .The particle size value were 2.184,2.374,4.834,5.125, and 8.336 nm and RMS roughness values were 0.161, 0.223,0.552,0.810 and 1.494 nm for films deposited at 250, 350, 450, 550 and 650 oC respectively. Optical properties measurements (Transmittance ,T , and Absorptance , A ,) of (TiO2) films showed high transparency. It is observed that maximum transmittance at 250 oC for wavelength range 320-900 nm. The optical band gap of the films has been found to be in the range 3.28-3.62 eV for the forbidden direct electronic transition and 3.45-3.75 eV for the allowed direct transition for the different heat treatment.

Keywords - Nanoanatase TiO2, Sol-Gel, XRD,AFM,Transmittance, Absorptance

[1]. S. Sharma, M. Vishwas, K. Rao and S. Mohan, Structural and optical investigations of TiO2 films deposited on transparent substrates
by sol–gel technique, Journal of Alloys and Compounds, 471 , 2009, 244–247.
[2]. F. Gamez, A. Reyes, P. Hurtado, E. Guille, J. A. Anta, and B. Martıez, Nanoparticle TiO2 Films Prepared by Pulsed Laser
Deposition: Laser Desorption and Cationization of Model Adsorbents, J. Phys. Chem. C , 114, 2010, 17409–17415.
[3]. C. Ayieko1, R. Musembi1, S. Waita1, B. Aduda1 and P. Jain, Structural and Optical Characterization of Nitrogen-doped TiO2
Thin Films Deposited by Spray Pyrolysis on Fluorine Doped Tin Oxide (FTO) Coated Glass Slides, International Journal of Energy
Engineering , 2(3), 2012, 67-72.
[4]. M. Mohammadi, N. Shahtahmaseb, M. Karimipour1, and R. Sarhadd, Characterization of nanostructured Nd-doped TiO2 thin film
synthesized by spray pyrolysis method: Structural, optical and magneto-optical properties, Indian Journal of Science and Technology,
5 (6) 2012, 2912-2916.
[5]. C. Ayicko, R. Musembi, S. Waita, and P. Jain, Structural and Optical Characterization of Nitrogen-doped TiO2 ThinFilms Deposited
by Spray Pyrolysis on Fluorine Doped Tin Oxide (FTO) Coated Glass Slides, International Journal of Energy Engineering,
2(3),2012, 67-72.
[6]. X. Han, G. Wang, J. Jie, X. Zhu, and J. Hou, Properties of Zn1-xCoxO thin films grown on silicon substrates prepared by pulsed
laser deposition, Thin Solid Films, 491, 2005, 249 – 252.

Abstract: Radon alpha activity concentration has been measured in 8 public hospitals in the three main governorates: Erbil, Duhok and Sulaymaniya -Iraqi Kurdistan region during two seasons summer and winter by using CR-39 nuclear track detectors. The CR-39 detectors were placed in the all hospitals for three floors (ground, first and second). . The highest average radon concentration was found to be in the Shaheed Dr.Aso hospital (Sulaymaniya) in winter season (131.73±9.42 Bq.m-3 ) , and the lowest was found in the Erbil Teaching hospital (Erbil) in summer season (30.15±2.83 Bq.m-3 ), this depended on the geological formation , type of building material, ventilation rate and the floor level. Therefore, the results showed that the average radon concentration and annual effective dose decreases gradually as the floor level increases. The highest and lowest of annual effective dose was found in ground and second floor, respectively.

Key words: CR-39NTDs, Indoor radon, lung cancer, ventilation and hospitals

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[8]. Ismail A H and Jaafar M S.,(2010). Relationship between radon concentration, ventilation rate and male infertility: A Case study in Iraqi Kurdistan. International Journal of Low Radiation .7(3) p.175-187.
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Abstract: Geomagnetic storms (GMSs) are stimulated by higher solar wind flow speed (VSW) and by a southward-directed interplanetary magnetic field (IMF Bz). Two kinds of flows dominate the large scale structure of solar wind: corotating flows and transient disturbances. Corotating flows are associated with spatial variability in coronal expansion and solar rotation, whereas transient disturbances are associated with episodic ejections of material into interplanetary space from coronal regions. The high speed streams originated from coronal interaction regions (CIRs) and transient disturbances are mostly caused by fast coronal mass ejections (CMEs). CMEs are the crucial link between solar activity and transient interplanetary disturbances and are responsible for major GMSs. CMEs eject magnetic flux into interplanetary space that produces abrupt increase in the northward component of Earth's magnetic field. There are two types of geomagnetic field variations termed as long-time variation and storm-time variations. The long-term variations are very useful to solar cyclical study of geomagnetic field variation as well as change in polarity of the Sun, climate change, plants growth rate and geological change of Earth's pole. The storm time variations also known as geomagnetic storm deals the various characteristics of GMSs and their connection with solar source activities and interplanetary magnetic fields. These variations are directly affect us and shows adverse effect in satellites, communication system and power losses. In the present study, we have analysed large geomagnetic storms (GMSs) associated with storm time index (Dst) decrease of more than 100 nT observed during solar cycle 23 and found 91 geomagnetic storms falling in our selection criteria. We have analyzed different characteristics of above GMSs and their association with different solar source activities.

Keywords: CMEs, CIRs, Dst, IMF, GMSs

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Abstract: It is a most advantage international level discovery for physics and technology. It solve many problems based on several field of life such as physical education, science, corporate world, engineering, industrial state, space science, mathematics, nuclear science, administration field, pre-planning, management and computer science etc. It is more easy and its representation is so more easy. We can easly provided this system in calculator, computer and many other technology based product. s n

Key Word : P n, P , (..), R, Pn

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Abstract: Ultrashort pulsed lasers have been widely used in measuring thermal diffusivity of thin solid specimens where the output temperature is detected by using fast radiation detector. One of the techniques used for measuring thermal diffusivity of submicron thin foils mostly for high conducting materials is done using converging thermal wave technique which is based on ultrashort pulsed laser. This article reported a moderate simplification of converging thermal wave technique is successfully done by using low cost camera's flash lamp and the temperature at the rear surface is detected using thermocouple. The theory of the present work is presented and the results obtained from the curve fitting are discussed. In addition simulation of heat propagation and temperature distribution in the samples is performed using visual finite element analysis as a guidance purpose regarding the present work. The results obtained from the present work have the deviation less than 5% compared to the standard converging thermal wave technique.

Keywords - converging thermal wave technique; thermal diffusivity; thin foils; flash lamp

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[8] Timothy Kehoe, Frank Murphy and Patrick Kelly, A Method for Measuring the Thermal Diffusivity of Intermediate Thickness Surface Absorbing Samples and Obtaining the Ratio of Anisotropy by the Converging Wave Flash Method. Int J Thermophys., 30(3), 2009, 987-1000.

[9] Sok Won Kim, Jong Chul Kim and Sang Hyun Lee, Analysis of thermal diffusivity by parameter estimation in converging thermal-wave technique. International Journal of Heat and Mass Transfer, 49, 2006, 611–616.

[10] J. Jauregui, Z. L. Wu, D. Schafer and E. Matthias, Thermal diffusivities of thin gold films. (Springer Series in Optical Sciences Vol 69: Photoacoustic and photothermal phenomena III ed. D. Bicanic, 1992, 682-687).

Abstract: The present work describes the use of ac complex impedance and electric modulus spectroscopy techniques to obtain the electrical parameters like electrical conductivity and activation energy of (Bi0.5Na0.5)0.94Ba0.06TiO3 (BNBT06)-PVDF 0-3 composites with (a) 10, (b) 20 and (c) 30 vol. percentage of BNBT06 in the frequency range 100 Hz–5MHz over a temperature range of 35oC-150°C. SEM micrographs showed almost homogeneous distribution of grains with less porosity for all the compositions and the EDAX patterns confirmed the presence of different constituent elements of the composite samples. Complex impedance spectroscopic analysis indicated the presence of non-Debye type dielectric relaxation in the composites. The bulk resistance showed the NTCR character of the composite materials and the presence of grain-boundary effect along with the bulk contribution, especially in the lower frequency and higher temperature regime, was indicated by the modulus spectroscopic analyses, thus confirming the non-Debye type of multiple relaxations in the system. The ac electrical conductivity data as a function of temperature also endorsed the NTCR character of BNBT06-PVDF 0-3 composites. The ac conductivity based activation energy data allowed insight into the mechanism of the occurring conduction processes in the composite system which are explained on the basis of hopping model of charge carriers.

Keywords- Ceramic-polymer 0-3 composites; Grains /grain-boundaries; Hopping conduction; Complex impedance/ modulus spectroscopy; Ac conductivity; Activation energy

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Abstract: In this paper new aspects concerning the current in the photoelectric effect are presented. By using the inverted form of the new intensity formula in optical emission spectroscopy, an explanation of many experimental current versus frequency observations are given. The ionization energy of many different elements has also shown to be important in the photo- electric effect in connection with this intensity formula. This paper also shows some ways to increase the current from a solar cell by structuring the surface of the solar cell. Some physical effects which are dominant in accordance to this structuring, are discussed.

Keywords : photoelectric effect, electron spectroscopy, laser experiments solar cells, texturisation

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Abstract: Previously, researchers were trying to replace the copper wires with the optical technology. They used photons instead of electrons to carry out the data within machines. The future of IC industry depends upon the speed and bandwidth requirements, but in metallic interconnections we have constraints on speed as well as bandwidth. With the advancement in computer technology we are now more dependent upon ultra fast data transfer rate between and within chips. Now, we can achieve high speeds with the use of optics, and if we integrate the optical components on a single silicon chip then it would allow the data to flow at a higher speed. This paper reviews the growth of silicon photonics compared to last few years and a promising future of photonics. Intel Corporation first announced its major breakthrough in 2004 based on silicon photonics (Moore's law). They developed a modulator based on silicon that operates at 50GHz. It was 50 times faster than the previous invention. In 2008 Intel declared that the data transfer rate can be increased further up to 1Tbps (bits per second).compatibility of silicon photonics with CMOS fabrication offers great advantages, such as low cost, high volume integration.

Keywords – Silicon, Modulators, Mach-Zehnder, SiGe, Detectors, Lasers, Avalanche Photodetector

[1] R. A. Soref.: "The past, present, and future of silicon photonics‟, IEEE J. Sel. Top. Quantum Electron, 12, (6), pp. 1678– 1687, 2006.

[2] Ali Okey, Thesis, SI-GE Photodetection Technologies for integrated optoelectronics, partialfulfilment of doctraldiss, Stanford University, 2007.

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[6] Ivan S. Maksymov,"Optical switching and logic gates with hybrid plasmonic–photonic crystal nanobeam cavities "Physics Letters A 375 ,2011 918–921.

Abstract: IR- transparent niobium substituted heavy metal oxide glass system in formula composition (100-x) BGO75- xNb2O5; 5 ≤ x ≤ 25 was fabricated by quenching and press molding technique. Glassy state was confirmed by XRD. Density ρexp varied 6.381 g/cc-7.028 g/cc ±0.06%. Modifying behavior of Nb2O5 was corroborated by rate of increase in theoretical volume Vth, measured volume Vexp and oxygen molar volume VMO-2. Nb5+ had larger cation radius and greater polarizing strength as compared to Ge4+ions. It replaced Ge4+sites introducing more NBOs in the network. Transformation temperatures Tg, Tx and Tp1 were 456 -469 oC ±2 oC, 516 -537 oC ±2 oC and 589 -624 oC ±2 oC respectively. In the range from room temperature to 400 oC the coefficient of linear thermal expansion α was 5.431±0.001*10-6 K-1 to 7.333±0.001*10-6 K-1. ΔT = Tx-Tg and ΔTP1 = TP1-Tg varied collinearly with increase in niobium concentration and revealed thermal stability against devitrification. The direct bandgap Eg values lay in 3.24 -2.63 eV ±0.01 eV range and decreased due to impurity states of Nb5+ within the forbidden band. Mobility edges obeyed Urbach law verifying amorphousness of the compositions. The IR-transparency window extended from 0.38 -6.1 μm in MIR which is wider than binary BGO glass as well as BGO single crystal.

Keywords: BGO75; band gap; IR-transparent; Thermal stability; Urbach law

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Abstract: Viscoelastic properties of liquid crystals are very important for applications like display technology. Certain molecules do not show a single phase transition from the crystalline to the liquid state on heating, but rather a series of transformations involving new phases possessing a state of aggregation intermediate bctwcen those of highly ordered crystals and of isotropic liquids. For this reason they are termed as liquid crystals (LC) or mesogens. Liquid crystals can be roughly categorized as lyotropic or thennotropic liquid crystals. Heating such crystalline solids or cooling them from their isotropic liquid phase can give rise to liquid crystalline phases. Several materials exist in the LC phase at room temperature, and many other room temperature LC materials can be produced by using mixtures of compounds. All components of the mixture need not necessarily be individually capable of forming LC phases in the latter case. An essential requirement for liquid crystalline or mesomorphic behaviour is that the molecules must be geometrically anisotropic in shape. The ultrasonic velocity measurement is a unique tool in characterizing the structure and properties of the system and provides significant information on the arrangement of matter in solutions and also finds an extensive application in studying the nature of intermolecular forces. In the present work, attempts have been made to investigate the behavior of cholesteryl oleyl carbonate at various concentrations also at different temperatures. The Ultrasonic velocity, viscosity and density are measured experimentally. In order to get more information on the nature and strength of molecular interaction, we have calculated the viscosity of cholestryl oleyl carbonate is done according to the statistical calculations [19,20].

Keywords: cholesteryl oleyl carbonate, viscosity, surface tension ,Ultrasonic Velocity,

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Abstract: Simulated scalar feed horns are capable of giving radiation characteristics of identical metallic corrugated feed horns. The impedance matching tapered throat profile of these horns is provided to the interior side of the E- plane walls. In the present study, by avoiding the abrupt angular variation caused by the interior tapered profile structure at the throat region, the possibility of obtaining better impedance matching is explored by giving the tapered throat profile to the exterior side of the E-plane walls. The radiation characteristics of the new horn are analyzed by comparing its radiation characteristics with that of an identical horn with interior throat profile structure. Though considerable improvement is not achieved in return-loss characteristics, improvements in side lobe, back lobe levels and gain are achieved.

Key Words – Microwaves, Feed horns, corrugated feed horns, dielectric loaded feeds, and simulated feed orns

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Abstract: The present study introduces records of radiation doses due to Natural Radioactivity measured in the investigations we have already carried out in various natural curative resources in Jordan, major of them include mineral and hot springs and the salt water and the volcanic mud of the Dead Sea. The investigated spots, in this study and other related studies, are located in Tafila, Irbid, Karak, and the Dead Sea. These data emphasis on new findings of different radiation dose rates, to identify the impacts of radiation exposures on public health. Using the assumption of radiation-Hormesis model about the astonishing effects of natural radiation doses, the author recommends that these doses existing in the investigated areas, improve the people health and increase average life span with less disease, and decrease incidence of cancer. This benefit will be added to promote health tourism, which have a tendency to be more active, and more competitive, where it challenges other kinds of tourism.

Key Words – Jordan, Hot springs, natural curative resources, natural radiation, radiation detection, absorbed dose rates, radiation hormesis.

[1]. Ajlouni, A., Al-Okour, A., and Ajlouni, A-W, High-Radiation Dose Equivalents in Jordanian Hot Springs. European Journal of Scientific Research,Vol.70 No.4 pp. 599-605, (2012)
[2]. Ajlouni, A-W., "Health Consequences of Nuclear Fission Products". J. Appl. Sci. Environ. Manage. Vol. 11(3) 11 – 14, (2007). www.bioline.org.br/ja
[3]. Ajlouni, A-W., and Al-Okour, A. "Fission Product Health Effects On Human Body". Pakistan Journal of Biological Sciences 10(19): 3405-3409, (2007). http://www.asninet.org/.
[4]. Ajlouni, A-W., "Deep Atomic Binding Hypothesis". ISBN: 978-3-8383-7930-2. LAP LAMBERT Academic Publishing AG & Co., Saarbrücken Germany, 2010. https://www.lap-publishing.com/.
[5]. Ajlouni A-W., Abdelsalam M., Abu-Haija O., Joudeh B. New findings: a very high natural radiation area in Afra hot springs, Jordan. Radiation Protection Dosimetry, pp. 1–4. DOI:10.1093/rpd/ncp028, (2009).
[6]. Ajlouni A-W., Abdelsalam M., Abu-Haija O., Almasa'efah Y. Radiation doses due to natural radioactivity in Afra hot spring. Int. J. Low Radia., 7(1). DOI: 10.1504/IJLR.2010.032770, (2010).
[7]. Ajlouni, A-W., Yacoub S. Almasa'efah, and M. Abdelsalam. "Nuclear Fission Products: from Source to Environment". Journal of Environmental Science and Technology. 3(4): 182-194, (2010). DOI: 10.3923/jest.2010.182.194.
[8]. AL-Amairyeen H. Radiation doses due to natural radioactivity in Wadi Bin Hammad, Al-Karak, Jordan. International Journal of the Physical Sciences Vol. 5(9), pp. 1486-1488, (2010).
[9]. Al-Okour, A. Radiation Doses Due to Natural Radioactivity in North-Shuneh Hot Springs, Jordan European Journal of Scientific Research ISSN 1450-216X Vol.51 No.4, pp.582-586, (2011).
[10]. Al-Okour, A. Ajlouni, A-W., Ajlouni, A.and Shakhatreh S., Radiation Doses due to Natural Radioactivity in Al Hammah Hot Springs, Jordan. Contemporary Engineering Sciences, Vol. 6, 2013, no. 3, 127 – 134, (2013).

Abstract: The exploration and exploitation of groundwater as a viable resource of water is safer and economical than surface water. Any effort towards the effective use of this precious resource is a service to the mankind. Groundwater is the only source of water supply for drinking and main source of irrigation in the study area. The increasing population and development activities have suddenly increased the demand for consumption of water. The increased demands have stimulated investigations oriented towards quantifications of this resource. The large scale abstraction of groundwater for irrigation, without proper planning and management has caused enormous environmental degradation. So, a detailed study is now essential for the conservation of this important resource in the specific area.

Key Words – Clay, groundwater, irrigation, population, topographic.

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