A Comparative Study on the Electrical Characteristics of Generating Plasma by Using Different Target Sources

In this research, the electrical characteristics of glow discharge plasma were studied. Glow discharge plasma generated in a home-made DC magnetron sputtering system, and a DC-power supply of high voltage as input to the discharge electrodes were both utilized. The distance between two electrodes is 4cm. The gas used to produce plasma is argon gas which flows inside the chamber at a rate of 40 sccm. The influence of work function for different target materials (gold, copper, and silver), - 5cm in diameter and around 1mm thickness - different working pressures, and different applied voltages on electrical characteristics (discharge current, discharge potential, and Paschen’s curve) were studied. The results showed that the discharge current and potential increase by increasing the applied voltage ranging between 300-700 V. Discharge current increased as working pressure increased in the beginning, and then semi-stabilized (slight increase) starting from 1×100 mbar, while discharge potential decreased at the beginning as working pressure increased and then semi-stabilized at the same point at which discharge current stabilized. The Paschen’s curves were compared with each other. It was concluded that the lower breakdown voltage was associated with lower work function of the (Au, Cu, and Ag) cathode material. Breakdown voltages were (395, 398, and 420) for Ag, Cu and Au respectively

Design and Construction of a Testing Platform and Estimating Attenuation Painting Reflectivity to Laser Beam

The project has been described the design and construction of a reliable optical testing platform used for evaluate the reflectivity of metal surfaces treated with special paintings required for laser beam attenuation. The platform comprises an Nd-YAG laser system which has been designed and fabricated with specifications to be compatible with their corresponding in laser range finder transmitters used for various applications. The reflectivity of various attenuating paintings, at different detection angles, has been observed. Moreover, the variation of the reflected energy with painting type and metal type to be painted has been studied experimentally. Results illustrated the existence of a definite angle, at which the reflectivity was maximum (specular reflection). On the other hand, samples with attenuation paintings have constant very low diffusive reflectivity and are independent of the detection angle

Comparative NO2 Sensing Characteristics of SnO2:WO3 Thin Film Against Bulk and Investigation of Optical Properties of the Thin Film

A comparative investigation of gas sensing properties of SnO2 doped with WO3 based on thin film and bulk forms was achieved. Thin films were deposited by thermal evaporation technique on glass substrates. Bulk sensors in the shape of pellets were prepared by pressing SnO2:WO3 powder. The polycrystalline nature of the obtained films with tetragonal structure was confirmed by X-ray diffraction. The calculated crystalline size was 52.43 nm. Thickness of the prepared films was found 134 nm. The optical characteristics of the thin films were studied by using UV-VIS Spectrophotometer in the wavelength range 200 nm to 1100 nm, the energy band gap, extinction coefficient and refractive index of the thin film were 2.5 eV , 0.024 and 2.51, respectively. Hall measurements confirmed that the films are n-type. The NO2 sensing characteristics of the SnO2:WO3 sensors were studied with various temperatures and NO2 gas concentrations. Both thin film and bulk sensors showed maximum sensitivity at temperature of 250 oC. Thin film sensors showed enhanced response in comparison to that of pellets

Photovoltaic Properties of CdS/Si Heterojunction Prepared by DC Plasma Sputtering Technique

CdS/Si heterojunction has been fabricated by dc plasma sputtering technique. Polycrystalline CdS films have been prepared by dc plasma sputtering technique on Si substrate. The current – voltage under illumination showed that the photocurrent increases with increasing incident illumination intensity for CdS/Si heterojunction. The CdS thin films have been sputtered under vacuum of (9×10-2 ,8×10-2, 6×10-2,5×10-2) mbar, theheterojunction has better photovoltaic properties. The open circuit voltage (Voc) and the short circuit current (Isc)were found to vary with working discharge pressure, and the efficiency is 6.72% at 50.3 mW/cm2

Spectrophotometric Determination of Sulfanilamide in Pure and in Synthetic Sample based on Condensation Reaction Method

A new, Simple, sensitive and accurate spectrophotometric methods have been developed for the determination of sulfanilamide (SNA) drug in pure and in synthetic sample. This method based on the reaction of sulfanilamide (SNA) with 1,2-napthoquinone-4-sulphonic acid (NQS) to form N-alkylamono naphthoquinone by replacement of the sulphonate  group of the naphthoquinone sulphonic acid by an amino group. The colored chromogen shows absorption maximum at 455 nm. The optimum conditions of condensation reaction forms were investigated by: (1) univariable method, by optimizing the effect of experimental variables; (different bases, reagent concentration, borax concentration and reaction time),     (2) central  composite design (CCD) including the effect of three experimental factors (reagent concentration, borax concentration, and reaction time). The linearity ranges of sulfanilamide are (5-30 µg.mL-1) at 455 nm with molar absorptivity (6.9568×104 - 7.0774×104 L.mol-1.cm-1), Sandell's sensitivity index (2.4753 - 2.4330 μg.cm-2) and detection limit of (0.546 – 0.536 µg.mL-1) for each procedure respectively. The results showed there are no interferences of excipients on the determination of the drug. The proposed method has been successfully applied for the determination of sulfanilamide in pure and in synthetic sample. Keywords: Spectrophotometric determination, Sulfanilamide, Central  composite design, 1, 2-napthoquinone-4-sulphonic acid (NQS)

Investigation the Activity of Pd Loading on Commercial Monolithic Catalyst in Automobile Exhaust Gases

Catalytic monolith reactors have numerous applications in industrial processes and as technical devices, so the focus is set specially on automotive catalytic converters. The present work aimed to study the experimental performance of monolith reactor on the oxidation and reduction of exhaust gas (NO, CO, and HC) which emitted from gasoline generator. Commercial and modified commercial ceramic monolith catalyst was used in the present work. The modified commercial catalyst was obtained by loaded Pd metal .A laboratory unit was constructed for this purpose where a versatile stainless steel monolith reactor of 0.02 m inside diameter and 0.2 m height was used.The catalytic performance of the catalysts was studied in the following operating conditions, in a border range of gas space velocity(17.69 – 44.23s-1), reaction temperature(373 – 673 K), bed length(0.075 – 0.15 m) and at atmospheric pressure and constant air/fuel ratio (14.6).The results show that the conversion of NO, CO and HC are slightly changed with the bed length . The conversion of exhaust gas reactant enhances in presence of water, increases with the increasing reaction temperature and decreases with increasing gas space velocity. Monolithic catalyst which loaded with 0.4% Pd gives high conversion compared with an commercial catalyst (unloaded) for the HC oxidation reaction more than CO oxidation and NO reduction

Simplified Convolutional Neural Network Model for Automatic Classification of Retinal Diseases from Optical Coherence Tomography Images

Optical coherence tomography (OCT) allows for direct and immediate imaging of the morphology of retinal tissue. It has become a crucial imaging modality for diagnosing eye problems in ophthalmology. One of the most significant morphological characteristics of the retina is the structure of the retinal layers, which provides important evidence for diagnostic purposes and is related to a variety of retinal diseases. In this paper, a convolutional neural network (CNN) model is proposed that can identify the difference between a normal retina and three common macular diseases: Diabetic macular edema (DME), Drusen, and Choroidal neovascularization (CNV). This proposed model was trained and tested on an open source dataset of OCT images also with professional disease classifications such as DME, CNV, Drusen, and Normal. The suggested model has achieved 98.3% overall classification accuracy, with only 7 wrong classifications out of 368 test samples. The suggested model significantly outperforms other models that made use of the identical dataset. The final results show that the suggested model is particularly adapted to the detection of retinal disorders in ophthalmology centers

Selected Indicators of Al-Najaf Road Network: Public Transportation Noise and Pollution

It is urgently necessary to improve the state of transportation and related infrastructure, especially given that the most important indicators of urban development gauge a city's progress. One of the most influential of these indicators is what is known as "smart transport, " which refers to transportation that utilizes modern communication and information technology technologies to address various challenges in various transportation sectors. The holy city of Najaf smart transportation strategy seeks to reduce dangerous levels of traffic-related noise and air pollution while enhancing various aspects of mobility and traffic flow indicators. This study aims to evaluate the performance of the existing traffic network and public transport in Najaf City and its interference with noise and air pollution at selected points for data gathering by using field measurements using cameras, noise meters, and pollution measurement devices. The study states that the public transport sector in Al-Najaf city is significantly poor as private cars are dominant by about 65% of traffic mix with values of pollution and noise above the standards. One of the most effective solutions to traffic problems is the implementation of intelligent transportation systems. Part of these strategies is establishing a tram network and raising road classes’ strategies by proposing some geometric design editing, U-turns reducing, and raised ramps additions

COVID-19 specialized diabetes clinic model for excellence in diabetes care: scientific perspective

While diabetes centers are well established by the Ministry of Health, there is no separate specialized diabetes clinics for COVID-19 patients (SDCs). There are several clinical diabetes centers throughout the Kingdom of Saudi Arabia, several of which have been developed through philanthropy funding; nevertheless, it is not obvious what distinguishes SDCs from a therapeutic viewpoint and what the potential would be for such centers. Through this context, we suggest a structure to direct the progress of SDCs. Defining protocols for wider adoption of SDCs as a means to enhance public safety and COVID-19 patient care efficiency (including consistency and satisfaction) and minimize health care expenses becomes increasingly essential when moving towards value-based sales and reimbursements away from service charges. It is wise to introduce innovative financial mechanisms to pay for diabetes that cannot be covered by fiscally limited private and university medical centers. We foresee potential clinical SDCs to be made up of a well-defined framework and six areas or foundations that act as basic guiding principles for the advancement of diabetes treatment skills that can be easily illustrated by stakeholders, including insurance facilities, consumers, payers and government departments