Herein, graphene nanocomposite of CuO–rGO is synthesized by simple precipitation reaction. Characterization by different techniques confirms the reduction of graphene oxide and formation of CuO–rGO. ...The CuO nanocrystals are uniformly distributed on graphene sheets. Neutron and X‐ray diffraction (XRD) prove the formation of single phase of CuO monoclinic crystal system with space group C2/c. Infrared spectroscopy shows vibration modes of graphene and CuO. Morphological characterization is carried out by scanning electron microscope (SEM) (SEM) and transmission electron microscope (TEM). It shows that the particle size ranges from 20 to 60 nm in which confirmed by four different theoretical approaches calculated from XRD peaks broadening data. The electronic properties using X‐ray photoelectron spectroscopy are also provided.
The reduction of graphene oxide and formation of CuO–rGO nanocomposite is achieved and confirmed; the crystallite size and micro strain are calculated and tested with four different theoretical approaches based on X‐ray diffraction peaks broadening. X‐ray photoemission spectroscopy and fast fourier transform infrared spectroscopy prove the reduction of graphene by disappearance of graphene oxide peak and prove the ability of using in energy storage applications.
•We characterised spatial and temporal variations in concentrations and loads.•The analysis is based on field data (17 campaigns – 8 location network).•We observed severe pollution downstream from ...the city of Fez (TN, TP and TCr).•The most polluted sites are under the influence waste water inputs.•The concentrations measured are above all environmental quality standards.
Oued Fez (one of the Sebou River tributaries – Morocco) allowed us to study and quantify the effect of the lack of wastewater treatment on surface water quality in semi-arid hydrological context. The analysis is based on field data collected from June 2009 to December 2011. Concentration and load patterns of nitrogen, phosphorus and chromium (used in the processing of leather) are compared in stable hydrological conditions during low flow and high flow periods in an eight-location sampling network.
The Oued Fez and the Sebou River are characterised by severe pollution downstream from the city of Fez, particularly TN (mainly NH4 and Norg), TP (mainly Ppart) and TCr. The most polluted sites are those directly under the influence of domestic and industrial waste water inputs, particularly tannery effluents. Obviously, the concentrations measured at these locations are above all environmental quality standards. Pollutant loads are very heavy in the Sebou River and can contaminate the river course for kilometres. Moreover, as the water of the Sebou River is used for the irrigation of vegetables, serious problems of public health could arise.
A better understanding of contaminant dynamics and self-purifying processes in these rivers will help implement actions and steps aimed at improving water quality in the Sebou River, which is the primary water supply source in Morocco and is used for agricultural and industrials purposes as well as for drinking water.
For a range of doses familiarly incurred in computed tomography (CT), study is made of the performance of Germanium (Ge)-doped fibre dosimeters formed into cylindrical and flat shapes. Indigenously ...fabricated 2.3 mol% and 6 mol% Ge-dopant concentration preforms have been used to produce flat- and cylindrical-fibres (FF and CF) of various size and diameters; an additional 4 mol% Ge-doped commercial fibre with a core diameter of 50 μm has also been used. The key characteristics examined include the linearity index f(d), dose sensitivity and minimum detectable dose (MDD), the performance of the fibres being compared against that of lithium-fluoride based TLD-100 thermoluminescence (TL) dosimeters. For doses in the range 2-40 milligray (mGy), delivered at constant potential of 120 kilovoltage (kV), both the fabricated and commercial fibres demonstrate supralinear behaviours at doses < 2 mGy, while a value of close to f(D) = 1 (linear) has been obtained for all dosimeters for doses > 4 mGy. In terms of dose sensitivity, all of the fibres show superior TL sensitivity when compared against TLD-100, the 2.3 mol% and 6 mol% Ge-doped FF demonstrating the greatest TL sensitivity at 84 and 87 times that of TLD-100. The TL yields for the novel Ge-doped silica glass render them appealing for use within the present medical imaging dose range, offering linearity at high sensitivity down to less than 2 mGy.
•The fabricated 2.3 mol% and 6 mol% Germanium (Ge)-doped fibres are investigated for computed tomography dosimetry.•Linearity index, dose sensitivity and minimum detectable dose (MDD) for the fibres are compared against TLD-100.•The novel Ge-doped fibres offering linearity at high sensitivity down to less than 2 mGy.
L’adénome thyroïdien toxique est une affection d’évolution progressive nécessitant un traitement radical. Le but de ce travail est d’évaluer la contribution de l’iode 131 dans le traitement des ...adénomes thyroïdiens toxiques en discutant ses modalités d’administration.
Il s’agit d’une étude rétrospective portant sur l’analyse de dossiers de patients traités par l’iode 131 pour adénome thyroïdien toxique. Le diagnostic de l’adénome toxique est confirmé par une scintigraphie et/ou échographie thyroïdienne avec un bilan hormonal thyroïdien. Les données recueillies sont l’âge, le sexe, les traitements antérieurs, le bilan biologique pré-irathérapie, l’activité reçue et le bilan biologique post-irathérapie.
L’effectif des patients compte 45 femmes pour sept hommes, soit un sex-ratio de 6,42. L’âge moyen de nos patients est de 53ans, avec des limites de 26 et de 80ans. L’âge moyen du traitement chez les femmes est de 57,33ans, alors qu’il est de 52,85ans chez les hommes. 98,07 % de nos patients traités par iode 131 sont passés en euthyroïdie ou en hypothyroïdie contre 1,92 % chez qui l’hyperthyroïdie a persisté. Ces résultats sont comparables à la littérature. Le contexte socioéconomique des patients marocains suggère l’élargissement des champs d’utilisation de l’iode 131 en matière d’adénome thyroïdien toxique grâce à son rapport efficacité/coût considérable.
Toxic thyroid adenoma is an evolutive condition requiring radical treatment. The purpose of this study is to evaluate the contribution of 131 in the treatment of toxic thyroid adenoma.
This is a retrospective study of patients treated with iodine 131 for toxic thyroid adenoma. The diagnosis of toxic adenoma is confirmed by scintigraphy and/or ultrasound. Data collected were age, sex, previous treatments, pre treatment hormonal status, radioiodine activity received and post therapy hormonal status.
We have 45 women to seven men with a sex ratio of 6.42. Mean age of our patients is 53years. Mean age for women at time of treatment is 57.33years and 52.85years for men. 98.07% of our patients treated with iodine 131 gained euthyroidism or became hypothyroid vs. 1.92% in whom hyperthyroidism persisted. These results are comparable to literature. Moroccan patients socioeconomic status pleads for an expansion of use of radioiodine in toxic thyroid adenoma due to its favourable cost/effectiveness ratio.
It has recently been shown that pervious concrete is a promising, effective technology as a permeable reactive barrier system for treatment of acid mine drainage (AMD). However, pore clogging also ...occurs simultaneously during AMD treatment. In the present study, mixtures of pervious concrete were made and used in a column experiment during which pore clogging occurred in the samples. Pore volume, connectivity and other parameters of pervious concrete were evaluated using five (5) different methods comprising the volumetric method (VM), linear–traverse method (LTM), image analysis (IA), falling head permeability test and X-ray microcomputed tomography. It was found that pervious concrete effectively removed from AMD, about 90 to 99% of various heavy metals including Al, Fe, Zn, Mn and Mg. Cr concentration significantly increased in the treated effluent, owing to leaching from cementitious materials used in mixtures. The VM and LTM gave statistically similar pore volume results, while IA’s values were 20 to 30% higher than those of the conventional methods. The falling head permeability test and IA were found to be effective in quantifying pore clogging effects. Pervious concrete exhibited high pore connectivity of 95.0 to 99.7%, which underlies its efficacious hydraulic conductivity.
Fabricated germanium (Ge)-doped optical fibre glow curve characteristics are investigated with respect to computed tomography (CT) dosimetry. 2.3 mol% and 6 mol% Ge-dopant concentration preforms have ...been used to produce flat and cylindrical fibres (FF and CF) of various size and diameter. The fibres are irradiated to doses of 20, 30 and 40 mGy for each of the beam qualities RQT 8 (100 kV), RQT 9 (120 kV) and RQT 10 (150 kV). The thermoluminescence (TL) kinematic parameters studied are maximum temperature (Tmax), activation energy (Ea) and peak integral (PI). The glow curve formations are reconstructed from the Windows®–based radiation evaluation and management system (WinREMS), deconvoluted using glow curve deconvolution (CGCD) analysis software. The structures of the glow curves are broad single or double-peaked, occurring at relatively high glow peak temperatures, TL response increases with radiation dose and peak height decreases with increasing energy, showing clear photoelectric dependence. The deconvoluted glow curves for all fibres are seen to consist of five individual glow peaks, P1 to P5, P1 being dominant in all cases other than for 6 mol% Ge-FF for which P3 is dominant due to the formation of a double-peaked glow curve. Tmax increases from P1 to P5 for all fibres, throughout the energy range used. P1 and P3 (6 mol% Ge-FF) have the lowest Ea, while P4 shows the greatest Ea for all fibres. The results indicate that electrons in P1 and P3 (6 mol% Ge-FF) are occupied at low energy traps while for P4, the electrons are trapped at a deeper energy level. The lowest PI value, indicative of the least number of electrons, is shown to be that of the deeper trap P4 for all energies investigated. This study provides support for the use of 6 mol% and 2.3 mol% preform fibres for CT dosimetry, each with similar kinetic parameters.
•Glowcurve characteristics of fabricated 2.3 mol% and 6 mol% Ge-doped optical fibres investigated for CT dosimetry.•Thermoluminescence kinematic parameters studied are: maximum temperature, activation energy and peak integral.•Majority of low energy electron traps are occupied using RQT beam quality radiation.
Recent years have seen a significant growth in Internet of Things (IoT) technology consisting of a large number of devices embedded with sensors and deployed to perform monitoring and actuation ...tasks. The IoT devices collect large volumes of data that is usually uploaded to cloud to perform analytics and predictions. One of the main challenges in IoT is the transportation of large-scale data collected over a period of time at a remote site. Cellular networks are already facing explosive growth of mobile data traffic due to the proliferation of smart devices and traffic-intensive applications. An alternate solution is to perform the data offloading, where a portion of data can be offloaded from primary links and transferred using opportunistic terminal-to-terminal (T2T) network that relies on direct communication between mobile users, without any need for an infrastructure backbone. However, such approach may lead to data loss and delay if dynamics of time-varying topology and mobility of nodes is not taken care of. To address this challenge, we propose three prediction-based offloading schemes that exploit the mobility patterns and temporal contacts of nodes to predict future data transfer opportunities. We have utilized the High-level Petri Nets to model and formally analyzed the communication processes of the proposed schemes. The new symbolic model verifier (NuSMV) has been employed for the verification of the three schemes against the identified constraints. The verification results affirm the correctness and scalability of the models. The protocols are evaluated with performance metrics, such as the delivery ratio, latency, and overhead. Our results indicate significant improvement in performance compared to existing approaches.
PDF
