515 research outputs found
The Effect of using Augmented Reality Technology on the Cognitive Holding Power and the Attitude Towards it Among Middle School Students in Al-Qurayyat Governorate, Saudi Arabia
The current study was to use augmented reality technology (ART) in the science course (SC) at the middle school level in Al-Qurayyat Governorate, Saudi Arabia, and to assess how it affected the students attitudes toward AR (ATAR) and cognitive holding power (CHP). The ART is utilized to enhance learning results, particularly when generating challenging, novel, and abstract scientific theories. The CHP measure, and the ATAR measure were developed for this research. 58 school students took part in this study. They have been split into two categories: the experimental group was in group one, and the control group was in group two. In each group, there were 29 students. Whereas the second group learned the SC through the conventional approach, the first group did it using ART. The outcomes demonstrated the first group (Experimental group) superiority. The study suggested that in order to improve students understanding of scientific topics, it is essential to increase knowledge of the value of ART
Effect of electronic cigarette (EC) aerosols on particle size distribution in indoor air and in a radon chamber
Particle size distribution is an important factor governing whether aerosols can be deposited in various respiratory tract regions in humans. Recently, electronic cigarette (EC), as the alternative of tobacco cigarette, has become increasingly popular all over the world. However, emissions from ECs may contribute to both indoor and outdoor air pollution; moreover, comments about their safety remain controversial, and the number of users is increasing rapidly. In this investigation, aerosols were generated from ECs and studied in the indoor air and in a chamber under controlled conditions of radon concentration. The generated aerosols were characterized in terms of particle number concentrations, size, and activity distributions by using aerosol diffusion spectrometer (ADS), diffusion battery, and cascade impactor. The range of ADS assessment was from 10 -3 μm to 10 μm. The number concentration of the injected aerosol particles was between 40 000 and 100 000 particles/cm 3 . The distribution of these particles was the most within the ultrafi ne particle size range (0-0.2 μm), and the other particle were in the size range from 0.3 μm to 1 μm. The surface area distribution and the mass size distribution are presented and compared with bimodal distribution. In the radon chamber, all distributions were clearly bimodal, as the free radon decay product was approximately 1 nm in diameter, with a fraction of ~0.7 for a clean chamber (without any additional source of aerosols). The attached fraction with the aerosol particles from the ECs had a size not exceeding 1.0 μm. © 2019 H. N. Khalaf, M. Y. A. Mostafa & M. Zhukovsky
The Photo Degradation of 2,3-dimethyl phenol in Drinking Water using Nano TiO2, ZnS and SnO2 Particles
The work presented in this paper is concernd with the preliminary study of semiconductors photochemical degradation of 2,3-dimethyl phenol by using powder and nanoparticles of TiO2,ZnS and SnO2. Degradation of 2,3-dimethyl phenol was carried out by using UV light at wave length of 267nm in the presence of oxygen.The absorpitivity of 2,3-dimethyl phenol decay was measured in the presence of UV light with capacity of 250 watt .The rate of degradation is increased with the weight of photocatalyst and reached maximum value at 0.1gm (TiO2), 0.5gm (ZnO) and 1gm (SnO2).In this paper,the effects of various operating parameters of the photolytic degradation of 2,3-dimethyl phenol are presented. It was found that, different parameters, such as type of photocatalyst composition, initial substrate concentration, and amount of catalyst can play an important role on photocatalytic degradation of 2,3-dimethyl phenol. It was also found that the type and particle size of nano TiO2, SnO2 and ZnS play an important factor for accelerating the photo degradation. The activity of nano particle was found in the order: TiO2> ZnS> SnO2. The results of photodegradation are represented by Lagmuir-Hinshelwood relationship and indicate that the results are Pseudo first order. The particle size of TiO2, SnO2 and ZnS was estimated using XRD technique. Keywords : Photodegradation, Drinking water, Nanoparticle
An Application of Using Support Vector Machine Based on Classification Technique for Predicting Medical Data Sets
© 2019, Springer Nature Switzerland AG. This paper illustrates the utilise of various kind of machine learning approaches based on support vector machines for classifying Sickle Cell Disease data set. It has demonstrated that support vector machines generate an essential enhancement when applied for the pre-processing of clinical time-series data set. In this aspect, the objective of this study is to present discoveries for a number of classes of approaches for therapeutically associated problems in the purpose of acquiring high accuracy and performance. The primary case in this study includes classifying the dosage necessary for each patient individually. We applied a number of support vector machines to examine sickle cell data set based on the performance evaluation metrics. The result collected from a number of models have indicated that, support vector Classifier demonstrated inferior outcomes in comparison to Radial Basis Support Vector Classifier. For our Sickle cell data sets, it was found that the Parzen Kernel Support Vector Classifier produced the highest levels of performance and accuracy during training procedure accuracy 0.89733, AUC 0.94267. Where the testing set process, accuracy 0.81778, the area under the curve with 0.86556
Infection of aerosol concentration on the radon decay products fractions
In this work, an experimental setup has been constructed to study the effect of aerosol concentration on the size distribution and unattached fraction of radon decay products. The experiments are conducted with 2 m3 standard radon chamber under controlled conditions (aerosol concentration, temperature and humidity). Number concentration and size distribution of aerosols inside radon chamber are measured with a Diffusion Aerosol Spectrometer (DAS 2702M, range from 5 nm to 10 μm). The activity size distribution of radioactive aerosols is estimated with diffusion battery. Number distribution diameter at low aerosol concentration has interval 50-100 nm. When additional aerosols injected to the radon chamber, distribution peak shifted to large diameters 70-150 nm at high aerosol particle concentration. At high aerosol concentration the unattached fraction fell sharply to 10-15% of the total activity compared to 50-70% when the aerosol concentration is low. The ratio between the fractions of the unattached and attached is in the range from 0.9 to 1.2 at low aerosol concentration. At high aerosol concentration, this ratio becomes from 0.09 to 0.14. © Published under licence by IOP Publishing Ltd
Particulate Matter Variation for Different Types of Cigarettes in Indoor Air
Particulate matter inhalation (PM) in second hand smoke is harmful to smokers and non-smokers. Various additions to cigarettes may affect the amount from PM. Exposure to PM is not only caused lung cancer but also increased risk of stroke breast cancer mortality. Although the main risks may be transferred to the distal lung by particulate matter, A few studies have been interested in studying PM. The present study aims to characterize PM emissions from three different types of cigarettes (Electronic cigarettes, tobacco cigarettes and IQOS cigarettes system). The experiments were carried out in a 65 m3 lab room with burning the three types of cigarettes separately. PM1, PM2. 5 and PM1 0 concentrations were measured simultaneously with aerosol diffusion spectrometer (ADS)1. The Electronic cigarettes achieved the highest values of particulate matter with 193, 1*103 and 2*103(μg/m3) for PM1, PM2. 5 and PM10 respectively. The value of surface area ranged from 3460 for IQOS cigarettes to 7482 for Electronic cigarettes. IQOS cigarettes got less particulate matter concentrations in different sizes. This may be due to the way IQOS cigarettes operate, as the tobacco is heated, not burned. © 2020 American Institute of Physics Inc.. All rights reserved
Attachment rate characteristics of different wide used aerosol sources in indoor air
In this work, six different aerosol sources, used in everyday life, were investigated to analyze parameters such as concentration, size distributions, and dynamics: regular and electronic cigarettes, incense, candles, mosquito coils, and cooking. During the experiments, the aerosol particle count ranged from 200 to 2·105 cm−3. The number, mass, and specific surface area of the aerosol size distributions were measured by a Model 2702 M diffusion aerosol spectrometer (DAS) with a range of 5 nm to 10 μm. The attachment rate of radon decay products to aerosol particles is calculated depending on their size distribution/ The use of household sources of aerosols (heat treatment of food, smoking, candles, etc.) result in an increase in the concentration of aerosol particles by more than an order of magnitude, mainly due to the generation of ultrafine aerosols with number median diameter 64–92 nm and GSD 1.45–1.84. The mass distribution is dominated by particles with a distribution maximum in the range of 2–5 μm. The attachment of radon decay products to aerosols is associated with ultrafine particles with diameter < 200 nm. The median diameter of the rate of attachment to aerosols is 130 nm. © 2021, Springer Nature Switzerland AG
Radioactive and non-radioactive aerosol permeability through two types of analytical filters
AFA analytical filter is the most used one of Petryanov filters in health protection and radiometric and analytical measurements. Therefore, the properties of this filter like efficiency and the permeability of the non-radioactive and radioactive aerosol particles are more important for accurate estimation and protection. AFA Petryanov filters (RSP-20 and RMP-20) are the most popular filters in Russia. In this work, an experimental setup has been constructed to estimate the permeability of the non-radioactive and radioactive aerosol particles through these two type of analytical filters. A standard radon chamber (2 m3), at Ural federal university is used to create radioactive aerosol. Non-radioactive aerosol or ambient aerosol is considered from ambient indoor air. Aerosol diffusion spectrometer (ADS) is used to measure aerosols concentration and number size distribution with range from 1 nm to 10 μm. The activity size distribution is determined with screen diffusion battery and the AIP-2 cascade impactor with range (0.5-20μm). The measurements are repeated before and after filters to study the PFs filters dispersion and permeability for non-radioactive and radioactive aerosols. ADS filter is used to measure the aerosol concentration and number size distribution before and after filters in ambient air with spatial construction. The effect of size modes of the non-radioactive and radioactive aerosols penetrating the filters is studied. At low aerosol concentration, the filters catch all free unattached radon decay products (RDPs) (1-5 nm) and the most collected activity with active median thermodynamic diameter, AMTD, ∼ 20 nm. In the radon chamber at high aerosol concentration, the activity of RDPs free unattached fraction nearly removed. The collected activity with AMTD ∼ 20-40 nm is more significant. © 2019 Published under licence by IOP Publishing Ltd
Cs-137 ACTIVITY IN FLY ASH FROM THERMAL ELECTRIC POWER STATIONS
In the present work, Cs-137 specific activity concentration is measured with a high effi-ciency gamma ray spectroscopy NaI(Tl) detector in fly ash samples from two thermal electric power stations in the south of Iraq (Al-Naserya and Al-Musaeb)
Dynamic of Particulate Matter for Quotidian Aerosol Sources in Indoor Air
A correlation between the mass concentration of particulate matter (PM) and the occurrence of health-related problems or diseases has been confirmed by several studies. However, little is known about indoor PM concentrations, their associated risks or their impact on health. In this work, the PM1, PM2.5 and PM10 produced by different indoor aerosol sources (candles, cooking, electronic cigarettes, tobacco cigarettes, mosquito coils and incense) are studied. The purpose is to quantify the emission characteristics of different indoor particle sources. The mass concentration, the numerical concentration, and the size distribution of PM from various sources were determined in an examination room 65 m3 in volume. Sub-micrometer particles and approximations of PM1, PM2.5 and PM10 concentrations were measured simultaneously using a diffusion aerosol spectrometer (DAS). The ultrafine particle concentration for the studied indoor aerosol sources was approximately 7 × 104 particles/cm3 (incense, mosquito coils and electronic cigarettes), 1.2 × 105 particles/cm3 for candles and cooking and 2.7 × 105 particles/cm3 for tobacco cigarettes. The results indicate that electronic cigarettes can raise indoor PM2.5 levels more than 100 times. PM1 concentrations can be nearly 55 and 30 times higher than the background level during electronic cigarette usage and tobacco cigarette burning, respectively. It is necessary to study the evaluation of indoor PM, assess the toxic potential of internal molecules and develop and test strategies to ensure the improvement of indoor air quality. © 2021 by the authors. Licensee MDPI, Basel, Switzerland
- …