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

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by sol–gel technique, Journal of Alloys and Compounds, 471 , 2009, 244–247.
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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.
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synthesized by spray pyrolysis method: Structural, optical and magneto-optical properties, Indian Journal of Science and Technology,
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by Spray Pyrolysis on Fluorine Doped Tin Oxide (FTO) Coated Glass Slides, International Journal of Energy Engineering,
2(3),2012, 67-72.
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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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