Engineering and Technology Journal

In this work In2O3 and Sn-doped ITO nanoparticles were prepared by sol-gel method and deposited on quartz substrate by dip coating technique at different doping concentration of (5, 10 and 15%). The samples were annealed at 550 oC at constant time (60 min). X-ray analysis confirmed the formation of polycrystalline cubic phase that decreases in crystalline size with increasing doping concentration. The optical properties of Sn-ITO nanostructure thin film were studied. The transmittance was measured in the wavelength range of (300nm to 1100 nm) for all thin films. The sensitivity towards NO2 gas was measured, when In2O3 was doped with Sn at different concentrations.

Recently, emerged an easy way to fabricate to a nano fiber-optic sensor (NFOS) using the inscription on the silica fiber. A simple etching reactor was developing to obtain reproducible tapers of desired diameter and length. This approach is reflected on-line monitoring of the etching using the transmitter and receiver system. The experimental data indicate that the diameter of the optical fiber decreases linearly with the time of survival of hydrofluoric acid, and etching was used at room temperature. In this study, we were examined the best rate of etching that used for the fabrication of such sensors. In the aforementioned technique, this method aims to determine the diameter of the reduced core and show the evolution of the two different processes from the nano fiber regime to the fixed regime in which the mode was remote from the surrounding evanescent field, intensity can propagate outside the segment fiber when the core diameter is less than 100 nm. To expire a easy-going has developed the diameter of the fibre after etching to the process has been done successfully.

In this research the bond of strontium hydroxyapatite that electrochemical deposited on TiO2 nanotube with biomimetically hydroxyapatite formed was in vitro investigated .The TiO2 nanotube synthesised by anodizing titanium metal and Ti-6Al-4V alloy using special electrochemical cell prepared for this perpous,the solution that used consisted from 70% vol. glycerene ,30% vol. water and 1.5 % wt. NH4F.Different concentrations of strontium hydroxyapatite (0,50,100)% were electrochemical deposited by using solution consist of Ca(NO3)2.H2O , (NH4)2HPO4 ,Na(NO3)2 and Sr(NO3)2 as required , then the samlpes was calcined at 500 ºC. Then the samples coated biomimaticaly by immersing in concentrated simulated body fluid (SBF×5) for 30 days in order to investigate the formation of naturally hydroxiapatite on them. The samples were calcined at 500 °C in tubular furnace under air atmosphere.The optical microscope ,XRD and SEM tests were achieved for each step ,and FTIR test for electrochemical coated samlples and biomimeticaly coated samples were made.The final result shows that the TiO2 nanotube is successfullysynthesized .The samples that coated with strontium hydroxyapatite (Sr 100% without calcium) achived agood formation of naturally hydroxyatite similar to bone composition than the others samples(that contain 50% Sr or 0% Sr)

Antibacterial fabrics were papered by using cotton fibers, CuSO4: 5H2O, ZnSO4 and TiO2. These cotton fibers were coated by nano thin film consists of titanium oxide, copper oxide and zinc oxide. The study of structural properties by XRD had indicated that the coated fabric thin film was polycrystalline. The topography of the thin films surface was identified by using a scanning electronic microscope (SEM) and optical microscope (OM). Optical properties were measured using optical spectrometer, the optical properties improve lead to increase in the effectiveness of anti-bacterial fabric during add titanium dioxide and zinc oxide to coated fabric by copper oxide, as well as improve the biological activity of fabric the thin film using the substance added (Methanol Sulphate) to a chemical solution during the initial preparation process of the coating fabric by oxide copper thin film. Biological characteristics have been studied for fabric against bacteria types Escherichia coli, Staphylococcus aureus and Bacillus cereus.

In this paper Nano powders were used a mono; copper oxide CuO and di metal oxides powder; titanium dioxide (TiO2) in fabrication of mortar. Powder particle size about (67.8 nm) for TiO2 and (55.7nm) for CuO with crystal structure tetragonal and monoclinic system respectively have been used. These Nano powders were used as additives to the mortar material (0.5, 2.5, 5, 7.5 wt %) in order to be used in construction application including covering building, and studies on these mortar. Investigation was done on the mortar including XRD, AFM, optical microscopy, physical and some mechanical properties, micro hardness and wear rate). Results shows that where there an increase in micro hardness and decrease in wear rate in the mortar with the addition of Nano powder. Also be reduced Ca(OH)2 soft crystals and formation fine grains structure and homogeneous and the abolition of flaws or cracks. And the mortar with the Nano addition has been improved, which make the addition of Nano material beneficial and have a promising future in modern construction application.

Electrospinning has recently emerged as a leading technique for generating biomimetic scaffolds made of synthetic and natural polymers for tissue engineering applications. PVA was dissolved in distilled water at concentration (10% wt). PVA 10% DW solution was prepared as biopolymeric materials for fabricating tissue engineered scaffolds by electrospinning, varying ambient temperature (25, 30, 35, 40, 45 and 50) ͦ C andinvestigated the ambient temperature effect on tissue nanofibers pore size. Scanning electron microscopy was utilized to profile the topography of individual electrospun fibers. Statistical measurements for each SEM images lead to measure the mean poresize of tissue obtained. Our results indicate that the average poresize of PVA fibertisues could be scaled down to mean values (132-300)nm smooth nanofibers without any beads, poresize decreased as ambient temperature increase to certain temperature at (40 °C) and retrain increasing at (45 and 50) °C temperature.

CdTenanorods have been prepared with the different reaction time period from 1hour to 3 hours. CdTenanorods visible photoconductive detector films have been prepared on porous silicon layer with etching time 10 min. The CdTenanorods crystallization has been studied, the crystalline structure appears hexagonal when the samples dried under vacuum at 400C° for 1h. The Hall measurements show that all samples were p – type semiconductor. The response time of the fabricated CdTe detector with different reaction time was measured by illuminating the samples visible light (Halogen lamp) and its values were decreased from 0.411ms for 1hour to 0.364ms for 3 hours, the photoresponsivity of the detector for reaction time 3hours was to be 3.25×10-6A/W and specific detectivity is found to be 1.05×106W-1Hz1/2cm.

Two types of carbon nanotubes (MWCNTs and SWCNTs) films were used tofabricate hydrogen gas sensors. CNTs films were deposited on porous silicon substrate by the drop casting method. The two sensors showed high sensitivity to hydrogen gas at different concentrations. Experimental results indicated that the SWCNTs have a better performance than MWCNTs. The SWCNTs gas sensor shows high sensitivity at 150oC with 29sec response time, whereas MWCNTs gas sensor shows best sensitivity at 200oC with 24sec response time.

Thin films of copper oxide nanoparticles mixed with 6% nickel oxide are deposited on glass and Si substrates with orientation (111) utilizing pulsed laser deposition technique for the manufacture of hydrogen gas sensor. The films are annealed in air at 400 °C for two hours, then the structural and morphological properties are characterized using x-ray diffraction and atomic force microscopy. The results of CuO:NiO/Si films are exhibited a polycrystalline monoclinic CuO and cubic NiO phases. In addition, the peak of Si located at 28.3º which refer to (111) direction. Furthermore, this peak becomes very broad with varying full width at half maximum for etching current density of 30 mA/cm2 at time of 30 min which confirms the formation of pores on the crystalline silicon surface. On the other hand, the average diameter of 84.31 nm and 34.98 nm for CuO:NiO on a glass substrate and PS, respectively, were obtained. A sponge-like structure is produced for PS which reveal that a part of pores transform to a larger structure. The peak sensitivity of 204.8% was observed at optimum operating temperature of 350°C.

First,ZnO nanorod s were su ccessfu lly synthesized by simple evaporation
method,u sing single stage controllable horizontaltu be fu rnace and qu artz tu be withou tcatalyst.The ZnO nano powd erwas mix ed with (10 and 20%)of TiO2 powd er(weightratio),then ZnO -TiO 2 thickfilms were synthesized u singsimple,low-cost efficient screen print techniqu e. The thick films were heated at 500 C ˚ for one hou rto remove the organic bind erand anyimpu rities.The prepared thickfilms were examined withX -Ray,and FESEM to stu d y the stru ctu raland morphology of the films,the X -ray results show that the films are polycrystalline with sharp and high intensity peaks indicating
high crystalinity of the product.The FESEM pictures show nanorods with diameters less than 100 nm and several micrometers in length
of ZnO withTiO 2 nanoparticles.ZnO -TiO 2 device was built up by electroding the thick films.The I-V characterization of the films were
studied in dark and light,then photo detection parameters were estimated and it was found to be efficient and high response in UV range detection

Nickel oxide (NiO) films were deposited by using a homemade DC reactive magnetron sputtering system at different working pressure in the range (0.05-0.14)mbar. The effect of working pressure on the structure, surface morphology, optical of NiO films was investigated. X-ray diffraction (XRD) results suggested that the deposited films were formed by nanoparticles with average particle size in the range of (8.145-29.195) nm. And the films are identified to be polycrystalline nature with a cubic structure along (111) and (101) orientation also Ni2O3 was found by XRD. The texture of the films was observed using SEM and AFM, it was observed that the grain size was increased with working pressure. The energy band gap was found to be in the range of (4.1 eV to 3.9 eV) When the film thickness varying from 73 nm to 146.9 nm.

Pulse laser deposition was used in this research by Nd:YAG laser with (λ=1064 nm average frequency 6 Hz and pulls duration 10 nm) to deposit an adopedZnO thin films with 0.02CuO with thickness (100) nm. X-ray diffraction pattern for Zinc oxide films with doping ratio of CuO shows that these films have polycrystalline hexagonal structure, and the X-ray diffraction patterns of porous silicon showed a broadening in the FHWM with increasing etching time. .From atomic force microscope of prepared samples show an average diameter of PS nanostructure. The operation temperature of gas sensor was studied for different temperature and found that the maximum sensitivity is (67.55) at T=350 cº.

Non-thermal atmospheric pressure plasma is new branch and tool in physics .Building generation dielectric barrier discharge (DBD) system at atmospheric pressure and studying of its thermal characterizations. The discharge was produced by applying high voltage (5-25 KV) and frequency (12 kHz). The thermal characterization was done by measuring discharge temperature at different applied voltage and different distances from barrier. The results indicate that the applied voltage and distance between electrodes effect on discharge (increasing or decreasing) according to operation conditions because they affects, as expected, the DBD plasma temperature decreases with the increasing of the dielectric thicknesses which results in the decrease of the discharge voltage across the gap, accordingly, the discharge across gap is also weakened.

Silver nanoparticles have found tremendous applications in the field of diagnostics and therapeutics. This work was aimed to study the antioxidant activity of Ag nanoparticles in water by scavengers the free radicals produced by radiation. The antioxidant properties of silver nanoparticles prepared by wire explosion technique have been evaluated using the 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) assay. Ag nanoparticles were characterized by UV-Visible absorption and the results showed surface Plasmon resonance absorption peaks around 397nm. The nanoparticle average size and its size distribution were determinate by Atomic Force Microscopy (AFM). The results showed that the absorption intensity varying systematically with increasing silver nanoparticles concentration with certain limits. So Ag nanoparticles were found to have significant antioxidant capacity and thus can be used as potential radical scavenger against deleterious damages caused by the free radicals.

This study we don't use any catalyst or buffer layer before the reaction by hydrothermal method was used to prepare ZnO nano rods and flowerlike. The process has taken place inside Teflon lined stainless steel autoclave with volume 50 ml (homemade). ZnO nano rods and flowerlike were successfully synthesized using ZnO nanoparticles (20 nanometer) and NaOH (concentrations 3M) was the starting materials for the chemical reaction under stirring. The suspension was transferred into a Teflon lined sealed stainless steel autoclave and kept at 90 0C for 24 h,48 h and 72 h. The influence of the synthesis process on the morphology, the crystallinity and structural properties are studied by X-ray diffraction and field emission scanning electron microscope (FE-SEM), the experimental pattern of the films show that diffraction peaks can be assigned to the Wurtzite hexagonal-shaped ZnO as shown in the FE-SEM pictures, also the morphology of the films studied by atomic force microscope shows that the prepared thick films have high roughness specially for the powder prepared 46 h .

The present work is concerned with the measurements of uraniumconcentrations in twenty surface soil samples from selected locations (some of them were measured for the first time as far as authors know) in Thi-Qargovernorate by using uranium fission fragmentU-235 (n-f), obtained by the bombardment of U-235 with thermal neutrons. The results have shown that, the highest uranium concentration in surface soil samples in the selected regions in Thi-Qargovernorate was found in T1 (AL-Refai) region , which was equal to (2.896 ppm), while the lowest uranium concentration was found in T18 (Garmat Beni Saeed) region which was equal to (0.779 ppm), with an average value of (2.077±0.4 ppm). The present results have show that the uranium concentrations in the studied surface soil samples were less than the allowed value (11.7 ppm) recommended by (UNSCEAR, 1993).

A novel CdO:In2O3nano composite has been synthesized by a pyrolysis method. The prepared nano composites have been carefully characterized using X ray diffraction and atomic force microscopy. The obtained results showed that the synthesized nano compositeCdo:In2O3 at optimum conditions has excellent grains. It was found that synthesized CdO:In2O¬3nano composite can be used as NO2 gas sensing to exhibit the highest sensitivity for NO2 at 200°C. The constructed sensor showed a very low detection limit of 5 ppm .

Gold thin films have been prepared and deposited by sputtering deposition system at 17 nm and 34nm thicknesson Ni-Cr-Mo alloy substrate.SEM, AFM, XRD, and Spectroscopic Reflectometer were used to characterize the thin films deposited. Electrochemical corrosion tests also have been carried out by measuring open circuit potential (Eo.c.p), Tafel extrapolation and cyclic polarization methods in artificial saliva solution at 37 0C with elements analysis of the corrosion solution by using atomic absorption spectroscopy (AAS). The results obtained indicate the ability to deposit gold thin films (17nm and 34 nm ) by sputtering deposition methodonNi-Cr-Mo alloy with uniformity and without defects, decreasethe roughness from 2.54 nm to 1.8 nm for gold nanocoated with 34nm and 17 nm respectively, FCC crystalline structure (111) with diffraction peaksresults from XRD, and improvement of the localized corrosion resistance by decreasing the hysteresis loop of nanocoated with 34 nm of gold compared with the uncoated alloy

Synthesis natural hydroxyapatite in different nanostructure shapes and sizes such that the toxicity is reduced to the minimum for an individual application. However, the synthesis and functionalization processes are accomplished using chemical method. The morphology of the HAP nanoparticles changes from rod to spherical. Rod shaped particle are found with length between 10-20 nm while the spherical particles are found with radius less than 10 nm. But for the pure HAP only rod morphology observed with the size ranging from 30-60 nm.

The cooling system of a car plays an important role in vehicle's performance, consists of two main parts, known as radiator and fan. Improving thermal efficiency of engine leads to increase the engine's performance, decline the fuel consumption and decrease the pollution emissions. This study presents an experimental study on enhancement of heat transfer in car radiator by using aluminum, copper and distilled water nanofluids. The range of nanoparticles concentrations used were in the range of (15 – 35 wt %). Two nanoparticles aluminum (Al (50nm)) and cupper (Cu (30nm)) used in this study and distilled water was used as base fluid (distilled water). The coefficient of heat transfer was studied with the effect of many parameters such as inlet temperature of nanofluid, Reynolds number, nanofluid concentration and types of nanoparticle.. Results show that Nusselt number increased with increasing of nanofluid inlet temperature, nanoparticle volume fraction and Reynolds number.The obtained results indicated that the enhancement in heat transfer for the nanofluid (Cu(30nm) + Dw) was greater than nanofluid (Al(50nm) + Dw) due to nanoparticles size and thermal conductivity of the cupper. The results indicated that using nanofluid as working fluid leads to higher heat transfer performance which is promoted the car engine performance and would reduce fuel consumption. Furthermore, Thermal conductivity for the nanofluids (Cu + Dw) was greater than nanofluids (Al + Dw) due to nanoparticles size and thermal conductivity for the cupper. It was indicated that the type and size of nanoparticle play an important role in enhancement of heat transfer rate.