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Evaluation of Radon Concentration and the Health Risk in the Offices of the Institute of Science and Technology of the “École Normale Supérieure”, Burkina Faso
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作者 Rouamba M. M. Jonathan Bambara Telado Luc +3 位作者 Doumounia Ali Kohio Nièssan Ouédraogo Soumaila François Zougmore 《World Journal of Nuclear Science and Technology》 2023年第3期41-54,共14页
The second most important cause of lung cancer after smoking is radon gas. Thus, the determination of indoor radon concentrations in residential buildings and workplaces is an important public health concern. The purp... The second most important cause of lung cancer after smoking is radon gas. Thus, the determination of indoor radon concentrations in residential buildings and workplaces is an important public health concern. The purpose of this research was to measure the concentration of radon gas in the offices of the Institute of Science and Technology and to evaluate the effective dose in the lungs and the risk of cancer. This study used Corentium’s AIR THINGS digital radon detector to determine the radon concentration in sixteen (16) offices. The digital radon detector air Things of Corentium was placed in each office for a minimum period of one week and the concentration values were recorded every 24 hours. The values recorded in each office were the short-term average and the long-term average during seven days of measurement. The short-term radon concentrations vary between 5.286 Bq/m<sup>3</sup> and 192.714 Bq/m3</sup> with an average of 48.01 Bq/m3</sup> and those in the long-term were between 6.143 Bq/m3</sup> and 172.571 Bq/m3</sup> with an average of 52.46 Bq/m3</sup>. The measurements in office N°6 and 13 were above the lower limit of 100 Bq/m3</sup> proposed by the WHO. The short-term and long-term effective doses in the lungs for offices N°6 and 13 were above the “normal” background level of 1.1 mSv/year proposed by UNSCEAR-2000. The short-term effective dose in the lungs for office N°6 was above the lower limit of 3 mSv per the ICRP-23 recommendation. The average number of lung cancer cases per year per million people was 15. 展开更多
关键词 RADON CONCENTRATION Absorbed Dose Effective Dose
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Effect of Nitrocellulose-modified HTPB Binder on the Thermal Decomposition Behavior of Ammonium Nitrate/Magnesium Solid Propellant 被引量:1
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作者 Mohammed Jouini Amir Abdelaziz +4 位作者 Ahmed Fouzi Tarchoun Fateh Chalghoum Yash Pal Weiqiang Pang Djalal Trache 《火炸药学报》 北大核心 2025年第4期372-381,I0004,共11页
An energetic binder based on hydroxyl-terminated polybutadiene(HTPB),doped with different ratios of nitrocellulose(NC)(10%,20%,30%,and 50%),was developed to study the effect of NC doping on the thermal decomposition b... An energetic binder based on hydroxyl-terminated polybutadiene(HTPB),doped with different ratios of nitrocellulose(NC)(10%,20%,30%,and 50%),was developed to study the effect of NC doping on the thermal decomposition behavior of a composite propellant(CP)comprising ammonium nitrate(AN)as an oxidizer and magnesium(Mg)as a fuel.Optimization of the propellant formulation was conducted using Chemical Equilibrium with Applications-National Aeronautics and Space Administration(CEA-NASA)software,which demonstrated an increase in specific impulse by 12.09 s when the binder contained 50%NC.Fourier-transform infrared spectroscopy(FTIR)analysis confirmed the excellent compatibility between the components,and density measurements revealed an increase of 6.4%with a higher NC content.Morphological analysis using optical microscopy showed that NC doping improved the uniformity and compactness of the surface,reduced cavities,and achieved a more homogeneous particle distribution.Differential scanning calorimetry(DSC)analysis indicated a decrease in the decomposition temperature of the propellant as the NC content increased,while kinetic studies revealed a 48.68%reduction in the activation energy when 50%NC was incorporated into the binder.These findings suggest that the addition of NC enhances combustion efficiency and improves overall propellant performance.This study highlights the potential of the new HTPB-NC energetic binder as a promising approach for advancing solid propellant technology. 展开更多
关键词 physical chemistry composite propellant HTPB NITROCELLULOSE energetic binder thermal behavior
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Experimental Study of Selective Batch Bio-Adsorption for the Removal of Dyes in Industrial Textile Effluents 被引量:3
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作者 Zakaria Laggoun Amel Khalfaoui +3 位作者 Kerroum Derbal Amira Fadia Ghomrani Abderrezzaq Benalia Antonio Pizzi 《Journal of Renewable Materials》 2025年第1期127-146,共20页
This research aims to study the bio-adsorption process of two dyes,Cibacron Green H3G(CG-H3G)and Terasil Red(TR),in a single system and to bring them closer to the industrial textile discharge by a binary mixture of t... This research aims to study the bio-adsorption process of two dyes,Cibacron Green H3G(CG-H3G)and Terasil Red(TR),in a single system and to bring them closer to the industrial textile discharge by a binary mixture of two dyes(TR+CG-H3G).The Cockle Shell(CS)was used as a natural bio-adsorbent.The characterizations of CS were investigated by Fourier transform infrared(FTIR),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy-dispersive X-ray spectroscopy(EDX)and Brunauer–Emmett–Teller(BET).The adsorption potential of Cockle Shells was tested in two cases(single and binary system)and determined by:contact time(0–60 min),bio-adsorption dose(3–15 g/L),initial concentration(10–300 mg/L),temperature(22–61°C)and pH solution(2–12).The study of bio-adsorption(equilibrium and kinetics)was conducted at 22°C.The kinetic studies demon-strated that a pseudo-second-order adsorption mechanism had a good correlation coefficient(R2≥0.999).The Langmuir isotherm modeling provided a well-defined description of TR and CG-H3G bio-adsorption on cockle shells,exhibiting maximum capacities of 29.41 and 3.69 mg/g respectively at 22°C.The thermodynamic study shows that the reaction between the TR,CG-H3G dyes molecules and the bio-adsorbent is exothermic,spontaneous in the range of 22–31°C with the aleatory character decrease at the solid-liquid interface.The study of selectivity in single and binary systems has been performed under optimal operating conditions using the industrial textile rejection pH(pH=6.04).CG-H3G dye is found to have a higher selectivity than TR in single(0–60 min)and binary systems with a range of 6–45 min,as shown by the selectivity measurement.It was discovered that CS has the capability to remove both CG-H3G and TR dyes in both simple and binary systems,making it a superior bio-adsorbent. 展开更多
关键词 Cockle shells bio-adsorption binary system dyes cibacron green terasil red selectivity
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Structural, electronic, and optical studies of chalcogenides stannite Cu_(2)CdSnX_(4)(X=S, Se, and Te): insights from the DFT study 被引量:1
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作者 Jamal GUERROUM Mohamed AL-HATTAB +3 位作者 Lhoucine MOUDOU Khalid RAHMANI Youssef LACHTIOUI Omar BAJJOU 《Optoelectronics Letters》 2025年第2期69-76,共8页
In this paper,we have calculated the structural,electronic,and optical properties of chalcogenide stannite Cu_(2)CdSnX4(X=S,Se,Te) materials.The calculations are based on the density functional theory (DFT) method and... In this paper,we have calculated the structural,electronic,and optical properties of chalcogenide stannite Cu_(2)CdSnX4(X=S,Se,Te) materials.The calculations are based on the density functional theory (DFT) method and are performed using the Cambridge sequential total energy package (CASTEP) code included in the Biovia Material Studio 20 software.All optical properties have been studied in a domain that extends energetically from 10 meV to 40 eV.Our results show that Cu_(2)CdSnX4(X=S,Se,Te) stannite exhibits absorption in the visible region,the refractive index decreases with increasing energy,and the refractive index values are n=3.2,3.73 and 3.75 for Cu_(2)CdSnS_(4),Cu_(2)CdSnSe_(4)and Cu_(2)CdSnTe_(4),respectively.They show also high conductivity,which implies that this material is promising for solar cells.These results argue in favor of the use of these materials in various potential applications.The density of state,band structures,and structural properties of Cu_(2)CdSnX4(X=S,Se,and Te) stannite are also studied in this work. 展开更多
关键词 materials ELECTRONIC refractive
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Multi-scale analysis of microstructural evolution and atomic bonding mechanisms in CoCrFeMnNi high-entropy alloys upon cold spray impact 被引量:1
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作者 R.Nikbakht M.Saadati +2 位作者 H.S.Kim M.Jahazi R.R.Chromik 《Journal of Materials Science & Technology》 2025年第5期263-277,共15页
Large interfacial strains in particles are crucial for promoting bonding in cold spraying(CS),initiated either by adiabatic shear instability(ASI)due to softening prevailing over strain hardening or by hydrostatic pla... Large interfacial strains in particles are crucial for promoting bonding in cold spraying(CS),initiated either by adiabatic shear instability(ASI)due to softening prevailing over strain hardening or by hydrostatic plasticity,which is claimed to promote bonding even without ASI.A thorough microstructural analysis is vital to fully understand the bonding mechanisms at play during microparticle impacts and throughout the CS process.In this study,the HEA CoCrFeMnNi,known for its relatively high strain hardening and resistance to softening,was selected to investigate the microstructure characteristics and bonding mech-anisms in CS.This study used characterization techniques covering a range of length scales,including electron channeling contrast imaging(ECCI),electron backscatter diffraction(EBSD),and high-resolution transmission microscopy(HR-TEM),to explore the microstructure characteristics of bonding and overall structure development of CoCrFeMnNi microparticles after impact in CS.HR-TEM lamellae were prepared using focused ion beam milling.Additionally,the effects of deformation field variables on microstructure development were determined through finite element modeling(FEM)of microparticle impacts.The ECCI,EBSD,and HR-TEM analyses revealed an interplay between dislocation-driven processes and twinning,leading to the development of four distinct deformation microstructures.Significant grain refinement occurs at the interface through continuous dynamic recrystallization(CDRX)due to high strain and temperature rise from adiabatic deformation,signs of softening,and ASI.Near the interface,a necklace-like structure of refined grains forms around grain boundaries,along with elongated grains,resulting from the coexistence of dynamic recovery and discontinuous dynamic recrystallization(DDRX)due to lower temperature rise and strain.Towards the particle or substrate interior,concurrent twinning and dislocation-mediated mechanisms refine the structure,forming straight,curved,and intersected twins.At the top of the particles,only deformed grains with a low dislocation density are observed.Our results showed that DRX induces microstructure softening in highly strained interface areas,facilitating atomic bonding in CoCrFeMnNi.HR-TEM investigation confirms the formation of atomic bonds between particles and substrate,with a gradual change in crystal lattice orientation from the particle to the substrate and the occurrence of some misfit dislocations and vacancies at the interface.Finally,the findings of this research suggest that softening and ASI,even in materials resistant to softening,are required to establish bonding in CS. 展开更多
关键词 Multi-length scale microstructure characteristics of bonding in cold spray DRX-induced softening and its role in bonding Interplay between twinning-induced hardening and DRX-driven softening EBSD&HR-TEM CoCrFeMnNi high entropy alloys
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Imaging and Quantifying the Diversity of Native NMDA Receptors
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作者 Sophie Shi David Stroebel +1 位作者 Laetitia Mony Pierre Paoletti 《Neuroscience Bulletin》 2025年第7期1307-1310,共4页
N-methyl-D-aspartate receptors(NMDARs)play crucial roles in neuronal plasticity and brain function by sensing key neurotransmitters,such as glutamate and glycine.In a tour-de-force,Zhang et al.[1]provide the first ima... N-methyl-D-aspartate receptors(NMDARs)play crucial roles in neuronal plasticity and brain function by sensing key neurotransmitters,such as glutamate and glycine.In a tour-de-force,Zhang et al.[1]provide the first images of native NMDARs directly extracted from rat brains,revealing key aspects of NMDAR assembly and diversity. 展开更多
关键词 neuronal plasticity native nmda receptors IMAGING GLUTAMATE brain function NEUROTRANSMITTERS GLYCINE
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Action Based Approach to Archaeological Reconstruction Projects: Case of the Karnak Temple in Egypt
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作者 Anis Semlali 《Journal of Civil Engineering and Architecture》 2025年第1期27-35,共9页
The proposed paper deals with a numerical approach that could better assist the archaeologist in the archaeological reconstruction projects.The goal of our research is to explore and study the use of computerized tool... The proposed paper deals with a numerical approach that could better assist the archaeologist in the archaeological reconstruction projects.The goal of our research is to explore and study the use of computerized tools in archaeological reconstruction projects of monumental architecture in order to propose new ways in which such technology can be used. 展开更多
关键词 Architectural heritage archaeological reconstruction process and actions action-based modeling architecture and complexity
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SNN-IoMT:A Novel AI-Driven Model for Intrusion Detection in Internet of Medical Things
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作者 Mourad Benmalek Abdessamed Seddiki Kamel-Dine Haouam 《Computer Modeling in Engineering & Sciences》 2025年第4期1157-1184,共28页
The Internet of MedicalThings(IoMT)connects healthcare devices and sensors to the Internet,driving transformative advancements in healthcare delivery.However,expanding IoMT infrastructures face growing security threat... The Internet of MedicalThings(IoMT)connects healthcare devices and sensors to the Internet,driving transformative advancements in healthcare delivery.However,expanding IoMT infrastructures face growing security threats,necessitating robust IntrusionDetection Systems(IDS).Maintaining the confidentiality of patient data is critical in AI-driven healthcare systems,especially when securing interconnected medical devices.This paper introduces SNN-IoMT(Stacked Neural Network Ensemble for IoMT Security),an AI-driven IDS framework designed to secure dynamic IoMT environments.Leveraging a stacked deep learning architecture combining Multi-Layer Perceptron(MLP),Convolutional Neural Networks(CNN),and Long Short-Term Memory(LSTM),the model optimizes data management and integration while ensuring system scalability and interoperability.Trained on the WUSTL-EHMS-2020 and IoT-Healthcare-Security datasets,SNN-IoMT surpasses existing IDS frameworks in accuracy,precision,and detecting novel threats.By addressing the primary challenges in AI-driven healthcare systems,including privacy,reliability,and ethical data management,our approach exemplifies the importance of AI to enhance security and trust in IoMT-enabled healthcare. 展开更多
关键词 Healthcare Internet of Medical Things artificial intelligence deep learning intrusion detection system
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Modeling stopping power of ions in plasmas using parametric potentials
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作者 Tanguy Barges Delattre Sébastien Rassou Jean-Christophe Pain 《Matter and Radiation at Extremes》 2025年第6期86-100,共15页
We present a study of the ion stopping power due to free and bound electrons in a warm dense plasma.Our main goal is to propose a method of stopping-power calculation expected to be valid for any ionization degree.The... We present a study of the ion stopping power due to free and bound electrons in a warm dense plasma.Our main goal is to propose a method of stopping-power calculation expected to be valid for any ionization degree.The free-electron contribution is described by the Maynard–Deutsch–Zimmerman formula,and the bound-electron contribution relies on the Bethe formula with corrections,in particular taking into account density and shell effects.The results of the bound-state computation using three different parametric potentials are investigated within the Garbet formalism for the mean excitation energy.The first parametric potential is due to Green,Sellin,and Zachor,the second one was proposed by Yunta,and the third one was introduced by Klapisch in the framework of atomic-structure computations.The results are compared with those of self-consistent average-atom calculations.This approach correctly bridges the limits of neutral and fully ionized matter. 展开更多
关键词 warm dense plasmaour free bound electrons maynard deutsch zimmerman formulaand parametric potentials ion stopping power bethe formula free electrons bound electrons
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Sustainable large-format additive manufacturing of composite molds with 45-degree deposition strategies
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作者 Pablo Castelló-Pedrero Javier Bas-Bolufer +2 位作者 César García-Gascón Juan Antonio García-Manrique Francisco Chinesta 《Defence Technology(防务技术)》 2025年第9期303-317,共15页
Military missions in hostile environments are often costly and unpredictable,with squadrons sometimes facing isolation and resource scarcity.In such scenarios,critical components in vehicles,drones,and energy generato... Military missions in hostile environments are often costly and unpredictable,with squadrons sometimes facing isolation and resource scarcity.In such scenarios,critical components in vehicles,drones,and energy generators may require structural reinforcement or repair due to damage.This paper proposes a portable,on-site production method for molds under challenging conditions,where material supply is limited.The method utilizes large format additive manufacturing(LFAM)with recycled composite materials,sourced from end-of-life components and waste,as feedstock.The study investigates the microstructural effects of recycling through shredding techniques,using microscopic imaging.Three potential defense-sector applications are explored,specifically in the aerospace,automotive,and energy industries.Additionally,the influence of key printing parameters,particularly nonparallel plane deposition at a 45-degree angle,on the mechanical behavior of ABS reinforced with 20%glass fiber(GF)is examined.The results demonstrate the feasibility of this manufacturing approach,highlighting reductions in waste material and production times compared to traditional methods.Shorter layer times were found to reduce thermal gradients between layers,thereby improving layer adhesion.While 45-degree deposition enhanced Young's modulus,it slightly reduced interlayer adhesion quality.Furthermore,recycling-induced fiber length reduction led to material degradation,aligning with findings from previous studies.Challenges encountered during implementation included weak part adherence to the print bed and local excess material deposition.Overall,the proposed methodology offers a cost-effective alternative to traditional CNC machining for mold production,demonstrating its potential for on-demand manufacturing in resource-constrained environments. 展开更多
关键词 Large format additive manufacturing Recycled material Composite materials Glass fiber MOLDS DRONES Wind turbine Racing car
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Spin(7)Is Unacceptable
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作者 Gaëtan Chenevier Wee Teck Gan 《Peking Mathematical Journal》 2025年第4期601-639,共39页
We classify to some extent the pairs of group morphisms Г→Spin(7)which are element-conjugate but not globally conjugate.As an application,we study the case where Г is the Weil group of a p-adic local field,which is... We classify to some extent the pairs of group morphisms Г→Spin(7)which are element-conjugate but not globally conjugate.As an application,we study the case where Г is the Weil group of a p-adic local field,which is relevant to the recent approach to the local Langlands correspondence for G_(2)and PGSp_(6)in Gan and Savin(Forum Math Pi 11:e28,2023).As a second application,we improve some result in Kret and Shin(J Eur Math Soc 25(1):75–152,2023)about GSpin7-valued Galois representations. 展开更多
关键词 Spin groups Local-global conjugacy Langlands correspondence
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MIL-91(Al) to Boost Solid–Solid Conversion Reactions in Li-Se Batteries
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作者 Tutku Mutlu-Cetinkaya Pieter Dobbelaere +4 位作者 Wim Temmerman Wenqing Lu Vanessa Pimenta Veronique Van Speybroeck Rezan Demir-Cakan 《Energy & Environmental Materials》 2025年第5期137-146,共10页
Lithium-Selenium (Li-Se) batteries have emerged as one of the most promising candidates for next-generation energy storage systems owing to superior electronic conductivity, impressive volumetric capacity, and enhance... Lithium-Selenium (Li-Se) batteries have emerged as one of the most promising candidates for next-generation energy storage systems owing to superior electronic conductivity, impressive volumetric capacity, and enhanced compatibility with carbonate electrolyte of selenium, comparable to sulfur. Despite these advantages, the development of Li-Se batteries is impeded by several intrinsic challenges, including volume expansion during the discharge process and the consequent sluggish reaction kinetics that undermine their electrochemical performance. In this study, MIL-91(Al) is used as an electrode additive to accelerate the one-step mutual solid–solid conversion reaction between Se and Li_(2)Se in the carbonate-based electrolyte. By doing so, uncontrollable deposition of Li_(2)Se is effectively mitigated, enhancing the electrochemical performance of the system. Thus, the use of MIL-91(Al) results in reduced internal resistance and faster Li-ion transfer rate, as analyzed by SPEIS and GITT. Ab initio calculations and molecular dynamics simulations further reveal that Li_(2)Se anchors to closely situated dangling oxygens of the phosphonate group of the organic linker of MIL-91(Al), inducing relaxation of the Li-Se-Li angle and stabilizing the overall structure. Accordingly, the MIL-91(Al)-containing Li-Se cells demonstrate a high specific capacity of approximately 530 mAh g^(−1) at 1C (675 mA g^(−1)) after 100 cycles and retaining a specific capacity of 320 mAh/g even under high current rate (20C) after 200 cycles. This research underlines the importance of the use of electrocatalyst/electroadsorbent materials to enhance the redox kinetics of the conversion reactions between Se and Li_(2)Se, thus paving the way for the development of high-performance Li-Se batteries. 展开更多
关键词 ab initio calculations and molecular dynamics simulations electrocatalyst/electroadsorbents lithium-selenium batteries metal-organic frameworks
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EXISTENCE RESULT FOR FRACTIONAL STATE-DEPENDENT SWEEPING PROCESSES
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作者 Shengda ZENG Abderrahim BOUACH Tahar HADDAD 《Acta Mathematica Scientia》 2025年第4期1471-1481,共11页
This paper addresses the evolution problem governed by the fractional sweeping process with prox-regular nonconvex constraints.The values of the moving set are time and state-dependent.The aim is to illustrate how a f... This paper addresses the evolution problem governed by the fractional sweeping process with prox-regular nonconvex constraints.The values of the moving set are time and state-dependent.The aim is to illustrate how a fixed point method can establish an existence theorem for this fractional nonlinear evolution problem.By combining Schauder’s fixed point theorem with a well-posedness theorem when the set C is independent of the state u(i.e.C:=C(t),as presented in[22,23]),we prove the existence of a solution to our quasi-variational fractional sweeping process in infinite-dimensional Hilbert spaces.Similar to the conventional state-dependent sweeping process,achieving this result requires a condition on the size of the Lipschitz constant of the moving set relative to the state. 展开更多
关键词 fractional differential inclusion Moreau's sweeping process prox-regular sets fixed point
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Analysis of the Effects of Passive Design for Improving Building’s Hygrothermal Comfort in the Sahelian Climate
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作者 Etienne Malbila Luc Bamogo David Yemboini Kader Toguyeni 《Journal of Building Material Science》 2025年第3期16-33,共18页
The present study aims to analyzse alternative passive design solutions for enhancing building energy and hygrothermal efficiency in the Sahelian zone.To achieve this,a model representing a standard single-storey ceme... The present study aims to analyzse alternative passive design solutions for enhancing building energy and hygrothermal efficiency in the Sahelian zone.To achieve this,a model representing a standard single-storey cementhollow block dwelling building and its relevant parameters was input into EnergyPlus,combined with OpenStudio or SketchUp.Scenarios were then analyzed to evaluate the effects of roof solar reflectivity,wall external insulation,natural ventilation,and their combined options.First,the base case,serving as a reference model,was validated using measured and simulated temperatures by calculating the scientific criteria,such as the NBME and CVRMSE coefficients recommended by the ASHRAE and IPVM standards.Additionally,the numerical simulation was used to compare interior temperatures,discomfort hours,thermal parameters,and the hygrothermal index(IHT)across seven cases studied.The reference model simulation indicated that cement-based hollow blocks are less effective for building envelopes in the Sahelian climate,with 51.48%discomfort hours and an IHT of 1.6,as shown in the Givoni diagram.The results revealed that the wall external insulation was the most effective passive solution,with 56%of comfort hours and an IHT of 0.7,which indicates the expected position of the model within the hygrothermal comfort zone of the Sahelian climate.Combining passive strategies yields the best scenario,resulting in a 28.25%reduction in annual total discomfort hours compared to the base case.These simulations demonstrated the effectiveness of accessible passive design solutions applicable in dwelling construction for the sustainable development of countries in the Sahelian climate. 展开更多
关键词 Optimization Methods Passive Solutions Hygrothermal Comfort Building’s Energy Efficiency Sahelian Climate
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Performance of Clay-Based Earth Bricks with Varying Sand Content:A Case Study of Lendi Soil,Douala
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作者 Ekoum Ewandjo Nkoue Arnold Madouma Madouma +7 位作者 Willy Chance Guimezap Kenou Roger Eno Fabien Kenmogne Benjamin Bahel Blaise Ngwem Bayiha Gilbert Tchémou Rayane Tiotsop Talonang Robert Nzengwa 《Journal of Building Material Science》 2025年第4期70-83,共14页
This study evaluates the influence of sand content on the mechanical behavior and water resistance of compressed earth bricks(CEBs)manufactured from Lendi clay(Douala,Cameroon).Twenty-seven specimens(prismatic and cub... This study evaluates the influence of sand content on the mechanical behavior and water resistance of compressed earth bricks(CEBs)manufactured from Lendi clay(Douala,Cameroon).Twenty-seven specimens(prismatic and cubic)were produced with three formulations:0%,30%and 60%sand substitution by dry mass,compacted at 2.5 MPa and cured for 7,14 and 28 days.Raw material characterization included particle size distribution,sand equivalent,Atterberg limits,bulk density and Proctor compaction.The clay displayed a liquid limit of 44.07%,plastic limit of 35.23%and plasticity index of 8.84%;optimum moisture content was 15.9%and maximum dry density 1.24 g·cm^(-3).Mechanical testing showed that pure-clay bricks achieved the highest compressive and flexural strengths at all ages(up to≈1.98 MPa and 0.56 MPa respectively).Although the 30%sand mix exhibited marginally higher early compressive strength(7 days),strength decreased substantially by 28 days.Capillary absorption tests revealed an important distinction:while 0%sand bricks exhibited continuous water uptake,they retained cohesion during immersion;conversely,30%and 60%sand bricks disintegrated into a slurry within seconds of immersion,evidencing severe loss of internal bonding.These findings indicate that,for this highly plastic tropical clay,sand acts primarily as a microstructural diluent that undermines long-term cohesion and durability despite short-term packing benefits.The study underscores the need for locally tailored formulations or stabilizers when designing durable CEBs for humid tropical climates. 展开更多
关键词 Earth Brick Clay Soil Physical Properties Mechanical Properties AGGREGATES
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Enhancing Energy Efficiency in Vapor Compression Refrigeration Systems Using Phase Change Materials
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作者 Rachid Djeffal Sidi Mohammed El Amine Bekkouche +5 位作者 Zakaria Triki Abir Abboud Sabrina Lekmine Hichem Tahraoui Jie Zhang Abdeltif Amrane 《Frontiers in Heat and Mass Transfer》 2025年第4期1129-1149,共21页
Refrigeration systems are essential across various sectors,including food preservation,medical storage,and climate control.However,their high energy consumption and environmental impact necessitate innovative solution... Refrigeration systems are essential across various sectors,including food preservation,medical storage,and climate control.However,their high energy consumption and environmental impact necessitate innovative solutions to enhance efficiency while minimizing energy usage.This paper investigates the integration of Phase Change Materials(PCMs)into a vapor compression refrigeration system to enhance energy efficiency and temperature regulation for food preservation.A multifunctional prototype was tested under two configurations:(1)a standard thermally insulated room,and(2)the same room augmented with eutectic plates filled with either Glaceol(-10℃ melting point)or distilled water(0℃ melting point).Thermocouples were calibrated and deployed to record air and PCM temperatures during freeze–thaw cycles at thermostat setpoints of and Additionally,a-30℃ -35℃ .defrosting resistor and timer were added to mitigate frost buildup,a known cause of efficiency loss.The experimental results show that PCM-enhanced rooms achieved up to 10.98℃ greater temperature stability during defrost cycles and reduced energy consumption by as much as 7.76%(from 0.4584 to 0.4231 kWh/h).Moreover,the effectiveness of PCMs depended strongly on thermostat settings and PCM type,with distilled water demonstrating broader solidification across plates under higher ambient loads.These findings highlight the potential of PCM integration to improve cold-chain performance,offering rapid cooling,moisture retention,and extended product conservation during power interruptions. 展开更多
关键词 Vapor compression refrigeration phase change materials(PCMs) energy efficiency thermal energy storage cold-chain preservation
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Sustainable Groundwater Management in Water-Scarce Regions:A Spatial Machine Learning Analysis from Rajshahi,Bangladesh
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作者 Sumaya Tabassum Likhon Chandra Roy +6 位作者 Amit Kumar Sarkar Yassine Ezaier Hader Ahmed Lghazi Youssef Hesam Kamyab Hussameldin Ibrahim Mohammad Yusuf 《Research in Ecology》 2025年第3期268-286,共19页
Ensuring the availability and sustainable management of water(SDG 6)is particularly challenging in dry regions like Rajshahi,Bangladesh,where communities rely heavily on groundwater with limited recharge potential.Iss... Ensuring the availability and sustainable management of water(SDG 6)is particularly challenging in dry regions like Rajshahi,Bangladesh,where communities rely heavily on groundwater with limited recharge potential.Issues such as declining water levels and contamination by iron,arsenic,and chloride compromise both user satisfaction and public health.This study aimed to assess groundwater quality risks through regional mapping to guide the installation depth of new water sources.In collaboration with the Department of Public Health Engineering(DPHE),data were collected from 7,388 tube wells across nine upazilas,including well depth,geographic coordinates,and contaminant concentrations.Water quality was evaluated against World Health Organization and Bangladesh standards.Machine learning(XGBoost)and spatial analysis were applied to model contaminant levels based on location and well depth.An initial model showed poor performance,but after identifying and correcting key errors,the refined model yielded significant improvements:R^(2) increased from 0.0345 to 0.62 for iron,from-0.0015 to 0.38 for arsenic,and from 0.12 to 0.71 for chloride.A comprehensive water quality risk map was developed by integrating these results at the upazila level.This map provides actionable insights for government agencies and NGOs to prioritize areas for water quality testing,remediation,and public awareness initiatives,contributing to more informed and sustainable water resource management in the region. 展开更多
关键词 Arsenic Contamination SDG 6 Iron Contamination Health Risk Groundwater Accessibility
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Evaluating the in vitro anti-diabetic activity of Bryonia dioica root extracts supported by molecular docking analysis
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作者 Zohra Fekhikher Nabila Benariba +9 位作者 Brixi Gormat Radia Reda Hassain Imen Abdelli Fatima Z.Sekkal Youssouf Kachekouche Warda Taibi Sohayb Bekkal Brikci Mohammed Terki Hanane Benramdane Sara Adjdira 《Digital Chinese Medicine》 2025年第2期219-233,I0025-I0028,共19页
Objective To evaluate the in vitro anti-diabetic effects of Bryonia dioica roots extracts,in-cluding water-acetone extracts and their ethyl acetate and butanol fractions,and chloroform-methanol extracts.Methods The to... Objective To evaluate the in vitro anti-diabetic effects of Bryonia dioica roots extracts,in-cluding water-acetone extracts and their ethyl acetate and butanol fractions,and chloroform-methanol extracts.Methods The total phenolic,flavonoid,flavonol,and saponin contents in the Bryonia dioica root extracts(chloroform-methanol extracts,water-acetone extracts and their ethyl acetate and butanol fractions)were determined using colorimetric methods with Folin-Ciocalteu,aluminum trichloride,and vanillin reagents,respectively.The in vitro anti-diabetic activity was evaluated by measuring the half-maximal inhibitory concentration(IC_(50))values of these root extracts againstα-amylase andα-glucosidase activities,evaluating their effects onα-amy-lase kinetics,quantifying the inhibition of bovine serum albumin(BSA)glycation using fluo-rometry to assess advanced glycation end products(AGE)production,and determining glu-cose uptake by isolated rat hemidiaphragm.Additionally,molecular docking analysis was conducted to investigate the binding affinity and interaction types between Bryonia dioica lig-ands(cucurbitacin B,bryogénin,vitexin,and isovitexin)and target enzymes,and a phyto-chemical-targets interaction network was constructed.Results Forα-amylase inhibition,ethyl acetate fraction demonstrated the most potent activi-ty(IC_(50)=145.95μg/mL),followed by chloroform-methanol extract(IC_(50)=300.86μg/mL).Water-acetone root extracts and their ethyl acetate and butanol fractions inhibited theα-glucosidase activity with IC50 values ranging from 562.88 to 583.90μg/mL.Both ethyl acetate and butanol fractions strongly inhibited non-enzymatic BSA glycation(IC_(50)=318.26 and 323.12μg/mL,respectively).The incubation of isolated rat hemidiaphragms with the ethyl acetate fraction(5 mg/mL)significantly increased glucose uptake(35.16%;P<0.0001),exceeding the effects of insulin(29.27%),chloroform-methanol extract(24.07%),and catechin(15.27%).Molecular docking revealed that cucurbitacin B exhibited the strongest docking scores againstα-amylase(-16.4 kcal/mol),andα-glucosidase(-14.2 kcal/mol).Compared with other ligands,isovitexin formed the maximum number of hydrogen bonds with theα-amylase active site residues(Asp300,Asp197,and Glu233),α-glucosidase residues(Ser13,Arg44,Met86,Gly10,Asp39,and Tyr131)and other residues(Arg195,Trp59,His299,and Tyr62).Network analysis identified 36 overlapping targets between Bryonia dioica phyto-chemicals and type 2 diabetes mellitus-associated genes,with cucurbitacins and polyphenols interacting withα-amylase,α-glucosidase,and Glut4 translocation pathway targets.Conclusion Bryonia dioica root extracts demonstrated promising in vitro anti-diabetic activi-ty through multiple mechanisms,including the inhibitory effect on digestive enzymes,pro-tein antiglycation potential,and enhancement of glucose uptake,suggesting their potential as a source for anti-diabetic drugs development. 展开更多
关键词 Bryonia dioica Glucose uptake Protein glycation Α-AMYLASE Α-GLUCOSIDASE Molecular docking Interaction network
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Effort minimization:A permanent,dynamic,and surmountable influence on physical activity
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作者 Silvio Maltagliati Layan Fessler +7 位作者 Qian Yu Zhihao Zhang Yanxia Chen Olivier Dupuy Ryan SFalck Neville Owen Liye Zou Boris Cheval 《Journal of Sport and Health Science》 2025年第4期43-47,共5页
Today, most people know that physical activity(PA) is beneficial for their health ^(1,2)and aspire to engage in regular PA.^(3,4)However, despite their awareness of the importance of PA, it is evident that the transit... Today, most people know that physical activity(PA) is beneficial for their health ^(1,2)and aspire to engage in regular PA.^(3,4)However, despite their awareness of the importance of PA, it is evident that the transition from intention to action is challenging-a situation that has important public health implications. According to the World Health Organization,^(5)1 person dies every 6 s worldwide from causes related to physical inactivity, which underscores the urgency of addressing this situation. 展开更多
关键词 World Health Organization physical activity pa effort minimization intention action public health physical inactivity physical activity
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Water Erosion Factors Modeling in the N’Zérékoré City, Republic of Guinea
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作者 Alhassane Diallo Oumar Keita +1 位作者 Ibrahima Sory Mamikouny CAMARA Boubacar Diallo 《Journal of Environmental Science and Engineering(A)》 2025年第4期206-216,共11页
Soil erosion from water has become a relevant issue at global level.In Guinea in particular,erosion has worrying effects,due to natural conditions and human impact,especially in the Nzérékore city in forest ... Soil erosion from water has become a relevant issue at global level.In Guinea in particular,erosion has worrying effects,due to natural conditions and human impact,especially in the Nzérékore city in forest region.This paper proposed a soil erosion modeling by rainfall effect in the prefecture of N'Zérékoré.To achieve this objective,monthly and annual rainfall data for the N'Zérékorécity were collected at the meteorological station over the period from 1980 to 2024.The analysis of rainfall aggressiveness was possible using the Fournier index.For data processing,we used Microsoft Excel,Python and the ARIMA(AutoRegressive Integrated Moving Average)model for soil aggressiveness predicted by rainfall.It was found that,from 2000 to 2009,erosion was higher compared to other periods with a rate of 60%,or 6 years of high rainfall aggression.From the periods 1990 to 1999 and 2010 to 2019,the lowest rainfall aggressiveness was recorded,with 60%or 6 years of low erosivity.However,from period 1980 to 1989 the highest rate(70%)of very high rainfall erosivity was recorded.The results show three levels of rainfall aggressiveness on an annual scale:a very high level of erosivity with a rate of 22.2%or 10 years,followed by a high level of 35.6%or 16 years of strong erosion.The moderate erosivity level corresponds to 42.2%or 19 years.The model predicts a stability of the erosivity index around 77.14 over the period 2025-2034.During the forty(45)years the rainfall erosivity index was very unstable characterized by strong erosion,however it would be stable in the next ten(10)years. 展开更多
关键词 Rainfall factor water erosion erosivity index N’Zérékoré
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