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The Impact of Sun Radiation on the Thermal Comfort in Highly Glazed Buildings Equipped with Floor Heating Systems

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Fluid Dynamics & Materials Processing 2023年第4期19卷 941-951页

作者： Abdelatif Merabtine Abdelhamid Kheiri Salim Mokraoui lyes Bellagh EPF School of Engineering Rosières-Prés-Troyes10430France Universitéde Lorraine Vandoeuvre-lès-Nancy54500France King Saud University Riyadh11451Saudi Arabia

Occupants of highly glazed buildings often suffer from thermal discomfort during the mid-seasons when no shadings are used in such buildings,especially when inertial heating systems are *** present study is devoted to evaluating the impact of long solar beam exposure on the internal thermal discomfort in glazed spaces when heating is implemented through a floor system.A comprehensive experimental study is carried out using an experimental bi-climatic chamber which is fully monitored and controlled,allowing realistic simulations of the dynamic movement of the sun patch on a heated *** findings show that a period of discomfort as long as 8 h can occur,and persist far after the sunbeam exposure *** this period,the heating slab’s surface temperature,considered from an average point of view,can attain 34°C while the indoor temperature reaches 26°*** conducted using a previously developed model display a good fit with the measurements.

关键词： Radiant system direct solar radiation thermal performance glazed spaces thermal discomfort

Numerical Simulation of Turbulent Swirling Pipe Flow with an Internal Conical Bluff Body

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Fluid Dynamics & Materials Processing 2021年第2期17卷 455-470页

作者： Jinli Song Nabil Kharoua lyes Khezzar Mohamed Alshehhi Khalifa University of Science and Technology Abu DhabiUnited Arab Emirates National Polytechnic School of Constantine ConstantineAlgeria

Turbulent swirling flow inside a short pipe interacting with a conical bluff body was simulated using the commercial CFD code *** geometry used is a simplified version of a novel liquid/gas separator used in multiphase flow *** turbulence models,belonging to the Reynolds averaged Navier-Stokes(RANS)equations framework,are *** are,RNG k-ε,SST k-ωand the full Reynolds stress model(RSM)in their steady and unsteady *** and unsteady RSM simulations show similar *** to other turbulence models,they yield the best predictions of the mean velocity profiles though they exhibit some discrepancies in the core *** influence of the Reynolds number on velocity profiles,swirl decay,and wall pressure on the bluff body are also *** Reynolds numbers generating a Rankine-like velocity profile,the width and magnitude of flow reversal zone decreases along the pipe axis disappearing downstream for lower Reynolds *** tangential velocity peaks increase with increasing Reynolds *** swirl decay rate follows an exponential form in accordance with the existing *** flow features would affect the performance of the real separator and,thus,the multiphase flow meter,noticeably.

关键词： Swirling pipe flow conical bluff body CFD separator

Structural,morphological and photoluminescence characterizations of Sm^(3+) doped Y_(2)O_(3) nano-sized phosphors synthesized by ultrasound assisted sol-gel method

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Journal of Rare Earths 2023年第1期41卷 51-59页

作者： lyes Lamiri Badis Kahouadji Mourad Berd Abdelmoumen Abdellatif Lotfi Benchallal Lakhdar Guerbous Salim Ouhenia Abdelhafid Souici Leila Amiour Abdelhalim Zoukel Madani Samah Department of TCSN University of BejaiaBejaia06000Algeria Department of Technology University of BejaiaBejaia06000Algeria Department of Technology Laboratory of LECVEUniversity of BejaiaBejaiaO6000Algeria Department of Physics of Materials University of Science and Technology Houari BoumedieneAlgiersAlgeria Laser Department/Nuclear Research Center of Algiers(CRNA) 02Boulevard Frantz FanonB.P.399Algiers16000Algeria Laboratory of Physical-chemistry University of BejaiaBejaia06000Algeria Phase Transformation Laboratory Universite Freres Mentouri Constantine 1Algeria Laboratory Physico-Chemistry of Materials Laghouat UniversityTechnical Platform of Physico-Chemical Analysis(PTAPC-Laghouat-CRAPC)LaghouatAlgeria

Nanosized 1 at% Sm^(3+)doped Y_(2)O_(3)powders were prepared by an ultrasound assisted sol-gel method.Y_(2)O_(3):Sm^(3+)powders crystallize in Y_(2)O_(3)pure cubic phase and XRD analysis shows that the as-used agitation protocol affects strongly the crystallite’s shape and mean *** recorded emission spectra under λ_(em)=600 nm exhibit two absorption bands;the first one is assigned to O^(2-)→Sm^(3+)charge transfer state(CTS) with a maximum absorption at 223 nm,and the second is due to intraconfigurational transition 4f^(5)-4f^(5) of Sm^(3+) with a maximum absorption at 407 *** 223 and 407 nm transitions are attributed to characteristics intra-configurational transitions of Sm^(3+).All emission spectra are dominated by reddish/orange luminescence located at 606 nm and assigned to ^(4)G_(5/2)→^(6)H_(7/2) *** is found that the photoluminescence intensity of samples obtained under excitation at 407 nm is 60 times smaller than that obtained under 223 nm *** time measurements of the ^(4)G_(5/2)→^(6)H_(7/2) luminescence transition indicate that decay time of nano-sized powder is significantly shorter than bulk material one.

关键词： Y_(2)O_(3):Sm^(3+)nano-sized powder Sol-gel method Ultrasound Charge transfer Photoluminescence Rare earths

Comparative Study of the Physicochemical and Microbiological Quality of Water from Wells, Boreholes and Springs Consumed in the Massissia District in Brazzaville, Republic of the Congo

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Open Journal of Applied Sciences 2023年第7期13卷 976-986页

作者： Martin Tchoumou Raison Félicien Louzayadio Mvouezolo Harmel Obami-Ondon lyes Chinalda Boulingui Makaya Adonaï Merci Malera Kombo Life and Plant Chemistry Unit Faculty of Sciences and Technologies Marien Ngouabi University Brazzaville Republic of the Congo Mechanical Energy and Engineering Laboratory School of Higher National Polytechnic Marien Ngouabi University Brazzaville Republic of the Congo

The Republic of Congo in the course of the last two decades has been marked by a strong demographic explosion. The increase of its population has been accompanied by a significant demand for drinking water. The Congolese populations in order to meet their water needs, have recourse to rainwater, surface water and groundwater, because it is easy to access. The city of Brazzaville, political capital of the Republic of Congo, is also affected by this problem. The study carried out here aimed to assess the physicochemical and microbiological parameters of groundwater (wells, boreholes and springs) consumed by the populations of the Massissia district. In this work the physicochemical parameters below were evaluated: the pH, the conductivity, the hardness, the major ions, the undesirable substances as well as some toxic elements (Lead, Cadmium, Iron and Zinc) thanks to techniques of colorimetry, potentiometry and spectrophotometry. The main microbiological parameters determined are E. Coli, Staphylococcus, Total Germs, Total Coliforms, Yeasts and Molds. The physicochemical analyzes revealed that these waters are acidic with pH values between 5 and 6.5, the nitrate concentration evaluated between 50 mg/L and 60 mg/L, and a presence of the element Cadmium at values variants between 0.01 and 0.5 mg/L, values greater than the standard required by the WHO. Microbiological analyzes revealed bacteriological contamination by presence of E. coli in wells and boreholes whose origin is faecal contamination, the presence of yeasts and molds, staphylococcus, Total germs and Total coliforms and Ps Aeuginosis in all water points, making these waters a real danger for consumers.

关键词： Water Quality Comparative Study Consumption Brazzaville

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杂志授权游戏淘金

现代广告 2010年第23期 106-106页

作者： Nat lyes 程甄(编译)

如今，一些商品均附带了杂志所授权的品牌名称，从家居生活类杂志《Real Simpte》授权的扫帚到娱乐类杂志《Maxim》的男性染发剂，再到《世界时装之苑》的楔形凉鞋，使用的都是杂志的名称。不过三大家用游戏主机Xbox、Play Station和Wi... 详细信息

如今，一些商品均附带了杂志所授权的品牌名称，从家居生活类杂志《Real Simpte》授权的扫帚到娱乐类杂志《Maxim》的男性染发剂，再到《世界时装之苑》的楔形凉鞋，使用的都是杂志的名称。不过三大家用游戏主机Xbox、Play Station和Wii的视频游戏却从未借助杂志的授权过度表现自己。这一次XboxgD杂志扯上关系了。

关键词：游戏主机杂志授权品牌名称 Real 家居生活 Xbox Play