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experimental approaches and analytical technique for determining heavy metals in fallen dust at ferrosilicon production factory in edfu, Aswan,egypt

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2005年第8期6卷 708-718页

作者： SOLTAN m.e RAGeH H.m RAGeH N.m AHmeD m.e Department of Chemistry Faculty of Science at Aswan South Valley UniversityEgypt Department of Chemistry Faculty of Science at Qena South Valley UniversityEgyptDepartment of Chemistry Faculty of Science at Qena South Valley UniversityEgyptDepartment of Environment Egyptian Ferroalloy Edfu AswanEgypt

In this study aimed to evaluate the pollution extent of metals and nonmetals inside and outside the ferrosilicon production factory in edfu, Aswan, egypt, raw materials (quartz, cokes, iron oxides), ferrosilicon alloy, silica fume, dust and suspended dust (at different sites) samples were collected from the factory, and fallen dust samples were collected from outside the factory, horizontally (at different sites and different distance and directions) and vertically (at different floors in the selected buildings). Gravimetric methods, X-ray fluorescence (XRF), flame photometer, wide range carbon determinator and atomic absorption spectroscopy tools were used for elements determination. The results indicating that the fallen dust and its element contents on southern factory walls being higher than those on eastern factory walls may be due to the nature of the dusts and effects of wind force and wind direction. Fallen dust levels in different regions outside the factory were found to be affected by the distance, direction and floors. The nature of dust samples was affected by gravity and the suspended dust in different factory units depended on the work capacity and method of handling materials by personnel in different production units. Silica fume was a complicated problem, had dangerous effect against the workers' health, and was characterized by high concentrations of SiO2(90.6%～93.6%) and heavy metals (mn, 420.6×10-6～520.3×10-6; Fe, 2354×10-6～2685×10-6; Co, 80.7×10-6～101.6×10 6 and Ni,5.3× 10-6～6.05× 10-6). The TSP (Total Suspended Particulate) levels in all factory units were higher than the recommended air quality value (70 μg/m3) under egyptian law. The effect of ferrosilicon factory fallen dust on the surrounding regions decreased with increasing distance between the factory and these regions. The suspended dust samples in the factory units and their components greatly exceeded national and international standards, so health and environmental criteria must be

关键词： Air pollution Dust Heavy metals Fallen dust

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Instability inspection of parametric vibrating rectangular mindlin plates lying on Winkler foundations under periodic loading of moving masses

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Acta mechanica Sinica 2019年第1期35卷 242-263,I0007页

作者： e.Torkan m.Pirmoradian m.Hashemian Young Researchers and elite Club Khomeinishahr Branch Islamic Azad UniversityKhomeinishahrIsfahan 84175-119Iran Department of mechanical engineering Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIsfahan 84175-119Iran

Parametric resonance is one of the most important issues in the study of dynamical behavior of structures. In this paper, dynamic instability of a moderately thick rectangular plate on an elastic foundation is investigated in the case of parametric and external resonances due to periodic passage of moving masses. The governing coupled partial differential equations (PDes) of the system, with consideration of the first-order shear deformation theory (FSDT) or mindlin plate theory, are presented and they are reduced to a set of ordinary differential equations (ODes) with time-dependent coefficients using the Galerkin procedure. All inertial components of the moving masses are adopted in the dynamical formulation. Instability survey is carried out for three different loading trajectories considerably interested in many practical applications of the issue, i.e. rectilinear, diagonal and orbiting trajectories. In order to analyze the resonance conditions, the incremental harmonic balance (IHB) method is introduced to calculate instability boundaries, as well as external resonance curves in parameters plane. A comprehensive study is done to assess effects of thickness ratio and foundation stiffness on the resonance conditions. It is found that an increase in the plate's thickness ratio leads to a reduction in values of critical parameters. moreover, it is observed that in creasing the foundation stiffness moves the in stability regions and resona nee curves to higher frequencies of the moving masses and also leads to further stability of the parametrically excited system at lower frequencies. Time response simulations done via Runge-Kutta method confirmed the results predicted by IHB method.

关键词： mass-plate interaction mindlin plate Parametric resonance external resonance Incremental harmonic balanee method

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enhancement of electric Conductivity in Transparent Glasse—Ceramic Nanocomposites of Bi_2O_3—BaTiO_3 Glasses

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Journal of materials Science & Technology 2013年第12期29卷 1166-1176页

作者： A.A.Bahgat m.G.moustafa e.e.Shaisha Department of Physics Faculty of ScienceAl-Azhar University

The frequency and temperature dependent electrical conductivity measurements for heat-treated binary glass system with composition of （lO0-x）Bi203-xBaTi03 （x = 20, 30, 40 and 50, in mol%） were carried out. The glass was prepared by melt quenching technique and their corresponding glass-ceramic nanocomposites were obtained by suitable heat treatment. Nanostructured behavior and electrical properties of these glasses and their corresponding glass-ceramic nanocomposites were studied. X-ray diffraction （XRD） and differential scanning calorimetry confirmed the amorphous nature of the glasses. moreover, XRD patterns of the samples indicate nanocrystallites embedded in the glass matrix. The Fourier transform infrared spectroscopy （FT-IR） spectral analysis showed that the band positions of glass system are within the wave number range of Bi06, Bi03 and Ti06 structural units. It is observed that the electrical conductivity is enhanced by 102-103 times in the transparent glass-ceramic nanocomposite phase. With further heat treatment, the conductivity decreased considerably in the stage of glass-ceramic nanocomposite phase as compared with the glassy phase sample. Therefore, partially devitrified phase is more suitable as cathode material in secondary batteries compared to its vitreous or fully crystalline counterpart. The conduction mechanism was confirmed to obey the adiabatic small polaron hopping （SPH）. AC conductivity measurements were performed as a function of temperature and frequency, showing a very slow increasing rate at low temperatures and then a fast rate at higher temperatures.

关键词： Barium titanat Transparent glass--ceramic nanocomposites DC electrical conductivity AC electrical conductivity Smallpolaron hopping

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Virtual Transmission Solution Based on Battery energy Storage Systems to Boost Transmission Capacity

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Journal of modern Power Systems and Clean energy 2024年第2期12卷 466-474页

作者： matías Agüero Jaime Peralta eugenio Quintana Victor Velar Anton Stepanov Hossein Ashourian Jean mahseredjian Roberto Cárdenas Coordinador eléctrico Nacional SantiagoChile PGSTech Montreal Canada ecole Polytechnique de montréal Montréal Canada University of Chile Santiago Chile Ieee

The increasing penetration of variable renewable energy(VRe)generation along with the decommissioning of conventional power plants in Chile,has raised several operational challenges in the Chilean National Power Grid(NPG),including transmission congestion and VRe *** mitigate these limitations,an innovative virtual transmission solution based on battery energy storage systems(BeSSs),known as grid booster(GB),has been proposed to increase the capacity of the main 500 kV corridor of the *** paper analyzes the dynamic performance of the GB using a wide-area electromagnetic transient(emT)model of the *** GB project,composed of two 500 mVA BeSS units at each extreme of the 500 kV corridor,allows increasing the transmission capacity for 15 min during N-1 contingencies,overcoming transmission limitations under normal operation conditions while maintaining system stability during *** dynamic behavior of the GB is also analyzed to control power flow as well as voltage *** results show that the GB is an effective solution to allow greater penetration of VRe generation while maintaining system stability in the NPG.

关键词： Battery energy storage system(BeSS) grid booster transient stability voltage stability electromagnetic transient(emT)

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exact Solutions of Nonlinear evolution equations in mathematical Physics Using the modified Simple equation method

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Chinese Physics Letters 2012年第6期29卷 1-4页

作者： e.m.e.Zayed S.A.Hoda Ibrahim Department of mathematics Faculty of ScienceZagazig UniversityP.O.Box 44519ZagazigEgypt

The modified simple equation method is employed to construct the exact solutions involving parameters of nonlinear evolution equations via the (1+1)-dimensional modified KdV equation,and the (1+1)-dimensional reaction-diffusion *** these parameters are taken to be special values,the solitary wave solutions are derived from the exact *** is shown that the proposed method provides a more powerful mathematical tool for solving nonlinear evolution equations in mathematical physics.

关键词： equation. exact equation

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A CONJUGATe GRADIeNT meTHOD FOR DISCReTe-TIme OUTPUT FeeDBACK CONTROL DeSIGN

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Journal of Computational mathematics 2012年第3期30卷 279-297页

作者： e1-Sayed m.e. mostafa Department of mathematics Faculty of Science Alexandria University Alexandria Egypt

In this paper, the discrete-time static output feedback control design problem is con- sidered. A nonlinear conjugate gradient method is analyzed and studied for solving an unconstrained matrix optimization problem that results from this optimal control prob- lem. In addition, through certain parametrization to the optimization problem an initial stabilizing static output feedback gain matrix is not required to start the conjugate gradi- ent method. Finally, the proposed algorithms are tested numerically through several test problems from the benchmark collection.

关键词： Output feedback control Nonlinear conjugate gradient methods Nonlinearprogramming.

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Nonintubated video-assisted thoracic surgery under epidural anesthesia—encouraging early results encourage randomized trials

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Chinese Journal of Cancer Research 2014年第4期26卷 364-367页

作者： eugenio Pompeo Department of Thoracic Surgery Policlinico Tor Vergata University

Nonintubated video-assisted thoracic surgery （VATS） that is also defined awake VATS entails thoracoscopic procedures performed by regional anesthesia in spontaneously ventilating,mildly sedated or fully awake patients.

关键词： VATS encouraging early results encourage randomized trials Nonintubated video-assisted thoracic surgery under epidural anesthesia

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measurement of the pion form factor for m_(ππ)～2 between 0.1 and 0.85 GeV^2 with the KLOe detector

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Chinese Physics C 2010年第6期34卷 686-691页

作者： Stefan e.müller Institut für Kernphysik Johannes Gutenberg-Universitt

The KLOe experiment at the φ-factory DAФPNe has measured the pion form factor in the range between 0.1 〈 mππ^2 〈 0.85 GeV^2 using events taken at √s = 1 GeV with a photon emitted at large polar angles in the initial state. This measurement extends the mππ^2 region covered by KLOe ISR measurements of the pion form factor down to the two pion production threshold. The value obtained in this measurement of the dipion contribution to the muon anomalous magnetic moment of △αμ^ππ= （478.5±2-0stat±4.8syst±2.9theo）·10^-10 further confirms the discrepancy between the Standard model evaluation for αμ and the experimental value measured by the （g-2） collaboration at BNL.

关键词： hadronic cross section initial state radiation pion form factor muon anomaly

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Visible light communication with efficient far-red/near-infrared polymer light-emitting diodes

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Light(Science & Applications) 2020年第1期9卷 1362-1372页

作者： Alessandro minotto Paul A.Haigh Łukasz G.Lukasiewicz eugenio Lunedei Daniel T.Gryko Izzat Darwazeh Franco Cacialli Department of Physics and Astronomy and London Centre for Nanotechnology University College LondonLondon WC1E 6BTUK School of engineering Newcastle UniversityNewcastle-upon-Tyne NE17RUUK Communications and Information Systems University College LondonLondon WC1E 6BTUK Institute of Organic Chemistry Polish Academy of Sciences01-224 WarsawPoland ISmN-CNR Institute for the Study of Nanostructured Materials40129 BolognaItaly

Visible light communication(VLC)is a wireless technology that relies on optical intensity modulation and is potentially a game changer for internet-of-things(IoT)***,VLC is hindered by the low penetration depth of visible light in non-transparent *** solution is to extend operation into the“nearly(in)visible”near-infrared(NIR,700-1000 nm)region,thus also enabling VLC in photonic bio-applications,considering the biological tissue NIR semitransparency,while conveniently retaining vestigial red emission to help check the link operativity by simple eye ***,we report new far-red/NIR organic light-emitting diodes(OLeDs)with a 650-800 nm emission range and external quantum efficiencies among the highest reported in this spectral range(>2.7%,with maximum radiance and luminance of 3.5 mW/cm^(2) and 260 cd/m^(2),respectively).With these OLeDs,we then demonstrate a“real-time”VLC setup achieving a data rate of 2.2 mb/s,which satisfies the requirements for IoT and biosensing *** are the highest rates ever reported for an online unequalised VLC link based on solution-processed OLeDs.

关键词： communication diodes IoT

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Assessing conservation practices in Amalacaxco Gorge (Izta-Popo National Park, Central mexico) using fallout 137Cs and Optically Stimulated Luminescence (OSL)

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Journal of mountain Science 2018年第3期15卷 447-460页

作者： mUNOZ-SALINAS e CASTILLO m Departamento de Geología Regional Universidad Nacional Autónoma de México Ciudad UniversitariaCiudad de MexicoMexico Laboratorio Nacional de Geoquimicay mineralogia Ciudad Universitaria Ciudad de Mexico Mexico

This study aims to assess conservation practices in Izta-Popo National Park(Central mexico) by evaluating the mechanisms of sediment transfer. We applied a methodology based on fallout ^(137)Cs and optically stimulated luminescence(OSL) analysis. This was tested in the upper catchment of Amalacaxco Gorge, selected for being one of the sectors of the park in which man-made actions have been implemented in last decades to favor forest growth in the alpine grassland and to reduce the effect of water runoff. We quantified the ^(137)Cs activity using gamma and beta spectrometry of fine sediment grains extracted from the surface of parcels of 0.4 m2 in areas of natural forest, natural alpine grassland, alpine grassland with conservation practices, ravines and trails. In general, ^(137)Cs values increases as local slope decreases as it was expected. The natural forest is the most stable area in terms of soil erosion and sediment accumulation and, mean ^(137)Cs activity was taken as reference to assess cumulative zones, with higher ^(137)Cs values and erosive, with lower. We found that trails are accumulative surfaces but in other areas, erosion predominates. man-made ditches, trenches and afforestation in the alpine grassland have higher ^(137)Cs values than thenatural grassland, which indicates that conservation practices are limiting the sediment transfer from hillslopes to channels, however, soil retention is less than in the natural grassland. Additionally, we evaluated the luminescence(OSL) values obtained from samples extracted from the sediment transported in ravines that are cutting into different sectors of the study area to assess the grade of resetting of fluvial materials. These luminescence results indicated that the sediment transported in ravines that are cutting into the natural forest and alpine grassland is bleached more efficiently than the sediment transported in the alpine grassland with conservation practices. Results of fallout ^(137)Cs and luminesce

关键词： Sediment transfer Soil erosion Natural protected areas Alpine grassland Caesium-137 Optically stimulated luminescence

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