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Critical review on anti-fatigue effects of natural dietary products:present insights and future trends
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作者 Syam P.K.Jeepipalli Nidesha Randeni +1 位作者 Bin Du Baojun Xu 《Food Science and Human Wellness》 2026年第2期453-472,共20页
Fatigue impacts both mental and physical health,significantly reducing quality of life and daily productivity.Natural bioactive compounds have emerged as promising agents to combat fatigue due to their multifaceted bi... Fatigue impacts both mental and physical health,significantly reducing quality of life and daily productivity.Natural bioactive compounds have emerged as promising agents to combat fatigue due to their multifaceted biological activities and minimal side effects.Key mechanisms through which these compounds exert anti-fatigue effects include enhancing energy metabolism,reducing oxidative stress,supporting mitochondrial integrity,modulating the immune response,and regulating neurotransmitter balance.Plant-derived metabolites such as flavonoids,ginsenosides,saponins,and polysaccharides,as well as animal-based peptides and microbial-derived substances,have demonstrated significant potential in alleviating fatigue symptoms in both clinical and preclinical studies.Additionally,fermented products like kefir,fermented rice bran,and yogurt enhance endurance performance,reduce lactate buildup,and improve glycogen storage,further contributing to fatigue mitigation.As consumer interest in natural alternatives grows,future research should prioritize improving the bioavailability,stability,and targeted delivery of these compounds.This review consolidates recent advances in the understanding of anti-fatigue mechanisms of natural products and highlights emerging directions for their development as functional foods and therapeutic agents. 展开更多
关键词 Anti-fatigue activity Plant metabolites Animal products Microbial products Fermented products Amino acid
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The effects of bio-inspired wing vein morphology on thrust generation in double-clap flapping-wing robots
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作者 Tien Van Truong Quoc-Viet Nguyen +1 位作者 Loan Thi Kim Au Hung-Truyen Luong 《Defence Technology(防务技术)》 2026年第1期257-276,共20页
Wing design is a critical factor in the aerodynamic performance of flapping-wing(FW)robots.Inspired by the natural wing structures of insects,bats,and birds,we explored how bio-mimetic wing vein morphologies,combined ... Wing design is a critical factor in the aerodynamic performance of flapping-wing(FW)robots.Inspired by the natural wing structures of insects,bats,and birds,we explored how bio-mimetic wing vein morphologies,combined with a bio-inspired double wing clap-and-fling mechanism,affect thrust generation.This study focused on increasing vertical force and payload capacity.Through systematic experimentation with various vein configurations and structural designs,we developed innovative wings optimized for thrust production.Comprehensive tests were conducted to measure aerodynamic forces,power consumption,and wing kinematics across a range of flapping frequencies.Additionally,wings with different aspect ratios,a key factor in wing design,were fabricated and extensively evaluated.The study also examined the role of bio-inspired vein layouts on wing flexibility,a critical component in improving flight efficiency.Our findings demonstrate that the newly developed wing design led to a 20%increase in thrust,achieving up to 30 g-force(gf).This research sheds light on the clap-and-fling effect and establishes a promising framework for bio-inspired wing design,offering significant improvements in both performance and payload capacity for FW robots. 展开更多
关键词 Flapping-wing robots Bio-inspired wing vein patterns Thrust generation Double clap-and-fling Fapping frequency
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Occurrence of microplastics in terrestrial habitats:Hazards and pollution abatement
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作者 Babalola Aisosa ONI Kingsley Chukwunonso AGU Samuel Eshorame SANNI 《Pedosphere》 2026年第1期317-341,共25页
Microplastics(MPs)are ubiquitous and pose an environmental risk.This review examined MP pollution in terrestrial ecosystems from a myriad of poorly understood sources.Knowledge regarding the occurrence sources,migrati... Microplastics(MPs)are ubiquitous and pose an environmental risk.This review examined MP pollution in terrestrial ecosystems from a myriad of poorly understood sources.Knowledge regarding the occurrence sources,migration behaviors,ecotoxicology,absorption mechanisms,and effects of MPs has also been fully summarized.Microplastics interact with contaminants,such as antibiotics,pesticides,heavy metals,etc.,and may act as vectors for contaminant transfer in terrestrial ecosystems.The transportation and retention of MPs in soil are governed by interactions among their inherent properties,such as size,shape,surface charge,and density.Interestingly,MP migration into soil is lacking research.The MPs and nanoplastics were also found in edible fruits and vegetables.The MP contamination in soil affects ecosystems,causing soil structure changes,fertility reduction,and pollutant leaching into groundwater.The MP concentration lies in the range of 43-2443 and 40-43000 items kg-1in agricultural and urban soils,respectively.This review provides a comprehensive roadmap for future research and a framework for soil MP risk assessment.Future studies on the uptake,accumulation,and translocation of MPs and their associated toxins by plants are essential for evaluating their risks to food security and human health.Research on MPs in terrestrial habitats lacks comprehensive data on their long-term persistence,degradation pathways,and interactions with soil components under varying environmental conditions.Additionally,limited understanding exists regarding MP impacts on soil biodiversity,pollutant mobility,and plant uptake,highlighting the need for innovative detection methods and effective pollution abatement strategies. 展开更多
关键词 CONTAMINANT ecological risk macroplastics nanoplastics plastic mulch risk assessment SLUDGE terrestrial ecosystem
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Unconfined compressive strength and small-strain shear modulus of soft marine clay improved by ordinary Portland cement and polyester fibers with modeling by Michaelis-Menten kinetics
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作者 Keeratikan Piriyakul Aruz Petcherdchoo +1 位作者 Koonnamas Punthutaecha Tanakorn Phoo-ngernkham 《Journal of Road Engineering》 2026年第1期134-147,共14页
This study proposes to use the unconfined compressive strength(UCS)and the bender element(BE)tests for determining the strength and the initial small-strain shear modulus of Bangkok soft marine clay improved by cement... This study proposes to use the unconfined compressive strength(UCS)and the bender element(BE)tests for determining the strength and the initial small-strain shear modulus of Bangkok soft marine clay improved by cement and polyester fibers.This study varies the content of admixed cement(1%–20%)and polyester fibers(0–20%),including the curing time(3–28 d)for preparing 360 samples.Moreover,this study uses the Michaelis-Menten kinetics concept to model cement hydration saturation.From the study,it is concluded as follows.The modelled results reveals that at least 10%cement and 1%polyester fiber are recommended to attain the 28-d UCS standards(294 kPa)for highway subgrade materials in Thailand.This also fulfils sustainable construction due to reducing normal-use cement from 20%to 10%.Unfortunately,the addition of polyester fibers into the Bangkok clay with at least 5%cement reduces shear modulus by 1.12–1.32 times.The Abram's relationship between shear modulus and the mixing-water-to-cement ratio is found time-dependent.From the composite theory,the BE detects the polyester fiber zone as a defect in the Bangkok clay(matrix)with 5%–20%cement.So,the 28-d shear modulus in the polyester fiber zone is negative(up to0.034 MPa for 20%fiber),similar to softening phenomenon in concrete cracking(negative stiffness).For the 28-d shear modulus of fiber zone,the optimum cement content is around 2%for the positive influences of polyester fibers.Experimentally,the timedependent normalized UCS for 10%and 20%cement is compatible with other studies,and its development rate increases with the cement content as 0.3017,0.3172 and 0.3204 for 5%,10%and 20%cement,respectively.The 28-d relationship between shear modulus and UCS shows that low-cement soft clay requires high polyester fiber content(5%–20%)to activate UCS improvement.However,the soft clay with enough cement(20%)causes the uniformly distributed UCS improvement. 展开更多
关键词 Bangkok soft marine clay Unconfined compressive strength Small-strain shear modulus Bender elements Polyester fibers Michaelis-Menten kinetics
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Assessing heavy metal pollution in urban children’s playgrounds:Comparative analysis of soil,dust,and moss bioaccumulation
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作者 Kaan Isinkaralar Paweł Świsło wski +4 位作者 Oznur Isinkaralar Małgorzata Rajfur Tuyet Nam Thi Nguyen Anna Di Palma Sneha Gautam 《Journal of Environmental Sciences》 2026年第2期700-712,共13页
Toxic heavy metals are ubiquitous environmental contaminants that can detrimentally influence human wellbeing,especially in the pediatric population.This study investigated soil,dust,and moss contamination collected f... Toxic heavy metals are ubiquitous environmental contaminants that can detrimentally influence human wellbeing,especially in the pediatric population.This study investigated soil,dust,and moss contamination collected from six urban children’s playground(parks 1 to 6)inÇankaya District with heavy metals(Cr,Cu,Cd,Ni,Pb,and Zn).The highest values of Cu(44.1 mg/kg),Ni(45.6 mg/kg),and Pb(44.2 mg/kg)were recorded from park dust.Moss samples showed higher values of Cr and Zn,respectively,as 68.7 mg/kg and 284.3 mg/kg.Of these,surface soil presented the lowest concentrations,with Zn showing the highest concentration at 259 mg/kg and Cd the lowest at 1.9 mg/kg.Moss showed the highest total metal loadΣ=482.1 mg/kg,followed by dustΣ=457.9 mg/kg and soilΣ=388.3 mg/kg.Significant differences of p<0.05 between the soil and other sample types,together with a strong correlation of R2=0.9443,may indicate that moss metal concentration is influenced by natural and anthropogenic sources by wet or dry deposition.Spatial analysis revealed metal hotspots near roadways,with Cr and Cu less concentrated in traffic areas.Significant variability was noted across parks,far from vehicular traffic and polluting land uses(parks 1 and 2),showing lower concentrations.Principal component analysis(PCA)and positive matrix factorization(PMF)identified four emission sources:diesel combustion,transportation,and fossil fuel combustion,which are transported up to several kilometers away from their sources and transferred to the soil by atmospheric deposition.Enrichment and bioaccumulation factors highlighted high Cd enrichment in dust,with significant bioaccumulation in mosses.Pollution index values varied,with parks under the pressure of vehicular traffic,commercial and industrial zones(park 6)showing the highest contamination.These local findings draw attention to the striking impact of land use decisions at a lower scale on the health risks of humans,especially children. 展开更多
关键词 Environmental risks Metal contamination BIOINDICATORS Urban parks Public health
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A review of anticorrosive,superhydrophobic and self-healing properties of coating-composites as corrosion barriers on magnesium alloys:Recent advances,challenges and future directions 被引量:1
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作者 Babalola Aisosa Oni Olusegun Stanley Tomomewo +2 位作者 Solomon Evro Andrew N.Misian Samuel Eshorame Sanni 《Journal of Magnesium and Alloys》 2025年第6期2435-2469,共35页
Magnesium and its alloys have gained relevance for their light-weight combined with a high value of strength-to-weight ratio,which makes them useful in fields such as aerospace,automotive as well as biomedical enginee... Magnesium and its alloys have gained relevance for their light-weight combined with a high value of strength-to-weight ratio,which makes them useful in fields such as aerospace,automotive as well as biomedical engineering.Unfortunately,the poor corrosion resistance of Mg-alloys limits their wide acceptance.Advanced composite coatings which are self-healing,superhydrophobic anti corrosive,and wear resistant are new synthetic materials for abating these challenges.The superimposed superhydrophobic surfaces help in minimizing their water contact,thus slowing down the electrochemical reactions on the surface of the alloys,while their self-healing characteristics autonomously aid in the repair of any induced micro-crack,defect or damage towards ensuring the metal's long-term protection.In addition,the integration of wear-resistant materials further improves the durability of coatings under mechanical stress.The most recent research efforts have been directed towards the preparation of multifunctional composites,with an emphasis on nanomaterials,functional polymers,and state-of-the-art fabrication techniques in order to take advantage of their synergistic effects.Some of the methods that have so far exhibited promising potentials in fabricating these materials include the sol-gel method,layer-by-layer assembly,and plasma treatments.However,most of the fabricated products are still faced with significant challenges ranging from long-term stability to homogeneous adhesion of the coatings and their scalability for industrial applications.This review discusses the recent progress and the relationship between corrosion inhibition and self-healing efficiencies of wear resistant polymer nanocomposite coatings.Some challenges related to optimizing coating performance were also discussed.In addition,future directions ranging from the consideration of bioinspired designs,novel hybrid nanocomposite materials,and environmentally sustainable solutions integrated with smart protective coatings were also proposed as new wave technologies that can potentially revolutionize the corrosion protection offered by Mg alloys while opening up prospects for improved performance and sustainability. 展开更多
关键词 Magnesium alloys CORROSION SUPERHYDROPHOBIC Self-healing coatings Water contact angle
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Zircon U-Pb age of the mafic microgranular enclaves in the ore-forming porphyry of the Tongchanggou Mo(Cu)deposit,northwestern Yunnan,China
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作者 Shou-kui Li Xue-long Liu +3 位作者 Shi-tao Zhang Jie-hu Zhou Bo-de Lu Yun He 《China Geology》 2025年第3期628-630,共3页
1.Objective.The Yidun arc within the Tethys-Himalaya metallogenic belt formed during the westward subduction of the Ganzi-Litang Ocean(237-206 Ma)during the Indosinian period,and then underwent the evolution stages of... 1.Objective.The Yidun arc within the Tethys-Himalaya metallogenic belt formed during the westward subduction of the Ganzi-Litang Ocean(237-206 Ma)during the Indosinian period,and then underwent the evolution stages of the collisional orogeny(206-138 Ma)and the post-collisional orogeny(135-75 Ma).In recent years,a series of large and medium-sized Late Yanshanian intracontinental porphyry-skarn Mo-Cu-W deposits have been discovered in the southern part of the Yidun arc,including Xiuwacu,Relin,Hongshan,Tongchanggou,and Donglufang(Fig.1a). 展开更多
关键词 yidun arcincluding tongchanggou mo cu deposit ZIRCON yidun arc ore forming porphyry collisional orogeny u pb age evolution stages
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Projectile impact and drop weight resistance of functionally graded fiber-reinforced magnetite aggregate concrete
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作者 Abbas Abbaspour Behnoud Ganjavi Mahdi Nematzadeh 《Defence Technology(防务技术)》 2025年第10期1-23,共23页
Many researchers have focused on the behavior of fiber-reinforced concrete(FRC)in the construction of various defensive structures to resist against impact forces resulting from explosions and projectiles.However,the ... Many researchers have focused on the behavior of fiber-reinforced concrete(FRC)in the construction of various defensive structures to resist against impact forces resulting from explosions and projectiles.However,the lack of sufficient research regarding the resistance of functionally graded fiber-reinforced concrete against projectile impacts has resulted in a limited understanding of the performance of this concrete type,which is necessary for the design and construction of structures requiring great resistance against external threats.Here,the performance of functionally graded fiber-reinforced concrete against projectile impacts was investigated experimentally using a(two-stage light)gas gun and a drop weight testing machine.For this objective,12 mix designs,with which 35 cylindrical specimens and 30 slab specimens were made,were prepared,and the main variables were the magnetite aggregate vol%(55%)replacing natural coarse aggregate,steel fiber vol%,and steel fiber type(3D and 5D).The fibers were added at six vol%of 0%,0.5%,0.75%,1%,1.25%,and 1.5%in 10 specimen series(three identical specimens per each series)with dimensions of 40×40×7.5 cm and functional grading(three layers),and the manufactured specimens were subjected to the drop weight impact and projectile penetration tests by the drop weight testing machine and gas gun,respectively,to assess their performance.Parameters under study included the compressive strength,destruction level,and penetration depth.The experimental results demonstrate that using the magnetite aggregate instead of the natural coarse aggregate elevated the compressive strength of the concrete by 61%.In the tests by the drop weight machine,it was observed that by increasing the total vol%of the fibers,especially by increasing the fiber content in the outer layers(impact surface),the cracking resistance and energy absorption increased by around 100%.Note that the fiber geometry had little effect on the energy absorption in the drop weight test.Investigating the optimum specimens showed that using 3D steel fibers at a total fiber content of 1 vol%,consisting of a layered grading of 1.5 vol%,0 vol%,and 1.5 vol%,improved the penetration depth by 76%and lowered the destruction level by 85%.In addition,incorporating the 5D steel fibers at a total fiber content of 1 vol%,consisting of the layered fiber contents of 1.5%,0%,and 1.5%,improved the projectile penetration depth by 50%and lowered the damage level by 61%compared with the case of using the 3D fibers. 展开更多
关键词 Steel fiber Projectile impact Gas gun Drop weight MAGNETITE Fiber-reinforced concrete(FRC)
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Condition Assessment of Existing RCC Building Using Non-Destructive Testing
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作者 Vikram Kumar Kiran Devi 《Journal of Building Material Science》 2025年第1期62-72,共11页
The growing importance of maintaining and extending the functional lifespan of reinforced concrete structures has resulted in an increased emphasis on non-destructive testing techniques as essential tools for evaluati... The growing importance of maintaining and extending the functional lifespan of reinforced concrete structures has resulted in an increased emphasis on non-destructive testing techniques as essential tools for evaluating structural conditions.Non-destructive testing procedures offer a notable benefit in assessing the uniformity,homogeneity,ability to withstand compression,durability,and degree of corrosion in reinforcing bars within reinforced concrete structures.This study aimed to evaluate the existing condition of partially constructed residential buildings in Rewari district,located in the state of Haryana.The reinforced concrete structure of the building had been completed eight years ago,however,the project was abruptly stopped.Prior to recommencing the construction,it is important to assess the present state of the structure in order to evaluate the deterioration in Reinforced Cement Concrete(RCC).The building’s state was evaluated by visually inspecting the building,conducting on-site examinations,and analyzing samples in a laboratory.The findings emphasize the assessment of the robustness and durability of concrete to ascertain the degree of deterioration and degradation in the structure.The study incorporates visual inspection,and non-destructive evaluation utilizing different instruments to evaluate the corrosion condition of reinforcing bars.In addition,selected RCC columns,beams,and slabs undergo chemical testing.It has been observed that the strength results and chemical results were within permissible limits. 展开更多
关键词 Condition Assessment Visual Inspection Distressed Condition NDT Methods Chemical Tests
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Construction of ternary structured Dy_(2)O_(3) nanorods/carbon spheres/few layered Dy_(2)WO_(6) nanohybrids for electrochemical supercapacitors
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作者 Sethumathavan Vadivel P.Sujita 《Journal of Rare Earths》 2025年第10期2222-2230,I0006,共10页
In this work,Dy_(2)O_(3)rods and layered Dy_(2)WO_(6)heterostructure were effectively interconnected by carbon spheres named Dy_(2)O_(3)/Dy_(2)WO_(6)/C-sph nanocomposite with a confined interface and it was fabricated... In this work,Dy_(2)O_(3)rods and layered Dy_(2)WO_(6)heterostructure were effectively interconnected by carbon spheres named Dy_(2)O_(3)/Dy_(2)WO_(6)/C-sph nanocomposite with a confined interface and it was fabricated using a simple solvothermal approach.These ternary nanocomposites were investigated by X-ray diffraction(XRD),UV-visible diffuse-reflectance spectroscopy(UV-DRS),Fourier transform-infrared spectroscopy(FT-IR),Raman,field emission scanning electron microscopy(FESEM)with energy disperse spectroscopy(EDS),high-resolution transmission electron microscopy(HRTEM),and X-ray photoelectron spectroscopy(XPS)analyses systematically.The XRD data expose that the synthesized materials are formed with a virtuous crystalline state.The charge storage properties and electrochemical performances of the as-synthesized nanocomposites and pure components were assessed with the help of cyclic voltammogram(CV),galvanostatic charge-discharge studies(GCD),and electrochemical impedance studies(EIS),respectively.The rare-earth-based novel Dy_(2)O_(3)/Dy_(2)WO_(6)/C-sph nanocomposite as wo rking electrodes established commendable electrochemical perfo rmances with a maximum specific capacitance value of 123 F/g at a current density of 0.4 A/g in 2.0 mol/L aqueous KOH solution.According to the stability measurements,it was observed that the initial capacitance was maintained at~93%even after 2500 cycles,indicating that good electrochemical stability with the lowest internal resistance values was obtained from EIS analysis.The electrochemical measurements suggest that the Dy_(2)O_(3)/Dy_(2)WO_(6)/C-sph nanocomposite enables great competence and can be used as alternative electrode material in supercapacitor devices to avail high energy efficiency in a sustainable approach. 展开更多
关键词 Dy_(2)O_(3) Dy_(2)WO_(6) Rare earths Carbon spheres Composite Supercapacitors
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A review on reactive oxygen species-induced mechanism pathways of pharmaceutical waste degradation:Acetaminophen as a drug waste model
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作者 Saba Humayun Maan Hayyan Yatimah Alias 《Journal of Environmental Sciences》 2025年第1期688-713,共26页
Innately designed to induce physiological changes,pharmaceuticals are foreknowingly hazardous to the ecosystem.Advanced oxidation processes(AOPs)are recognized as a set of contemporary and highly efficient methods bei... Innately designed to induce physiological changes,pharmaceuticals are foreknowingly hazardous to the ecosystem.Advanced oxidation processes(AOPs)are recognized as a set of contemporary and highly efficient methods being used as a contrivance for the removal of pharmaceutical residues.Since reactive oxygen species(ROS)are formed in these processes to interact and contribute directly toward the oxidation of target contaminant(s),a profound insight regarding the mechanisms of ROS leading to the degradation of pharmaceuticals is fundamentally significant.The conceptualization of some specific reaction mechanisms allows the design of an effective and safe degradation process that can empirically reduce the environmental impact of themicropollutants.This review mainly deliberates themechanistic reaction pathways for ROS-mediated degradation of pharmaceuticals often leading to complete mineralization,with a focus on acetaminophen as a drug waste model. 展开更多
关键词 Wastewater treatment Ionic liquid Hydroxyl radical Superoxide Pharmaceutical contaminant Advanced oxidation process Deep eutectic solvent Hydrogen peroxide
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Navigating Solar Thermal Desalination:A Comprehensive Review of Materials Selection Criteria
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作者 M.A.Zaed K.H.Tan +1 位作者 R.Saidur A.K.Pandey 《Transactions of Tianjin University》 2025年第5期524-553,共30页
Global water scarcity,intensified by climate change and population growth,necessitates sustainable freshwater solutions.Solar thermal desalination offers promise due to its energy efficiency,yet optimizing system perf... Global water scarcity,intensified by climate change and population growth,necessitates sustainable freshwater solutions.Solar thermal desalination offers promise due to its energy efficiency,yet optimizing system performance hinges critically on material selection,particularly for photothermal absorbers and their substrates.While extensive research addresses photothermal nanomaterials,substrate materials vital for structural integrity,thermal management,and interfacial stability remain underexplored.This review comprehensively examines current advances in solar evaporator components,evaluating photothermal materials and substrates against key selection criteria:thermal conductivity,stability under harsh conditions,scalability,and compatibility.We analyze diverse substrate materials(e.g.,metals,ceramics,polymers,bio-based,and aero-gels)and their synergistic roles in enhancing evaporation efficiency and durability.Critical gaps in large-scale feasibility,long-term stability under variable solar flux,and cost-performance trade-offs are identified.The review also highlights emerg-ing trends such as 3D-printed substrates and bio-inspired designs to overcome salt accumulation and fouling.By addressing these challenges and outlining pathways for scalable implementation,this work aims to advance robust,economically viable solar thermal desalination technologies for global freshwater security. 展开更多
关键词 DESALINATION Solar desalination Photothermal materials Substrate materials SUSTAINABILITY
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Effect of Different Land Use Types on Nutrient Distribution across Soil Depth in Busega Wetland, Uganda
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作者 Daniel Iku Abuni Sylvia Nyamaizi +1 位作者 Doreen Mbabazize Christine Atugonza 《Open Journal of Soil Science》 2025年第1期84-101,共18页
Wetlands play a number of vital roles in the ecosystem, such as serving as nutrient sinks, preventing floods, storing carbon, and filtering water. Encroachment on wetlands has led to substantial economic and environme... Wetlands play a number of vital roles in the ecosystem, such as serving as nutrient sinks, preventing floods, storing carbon, and filtering water. Encroachment on wetlands has led to substantial economic and environmental losses, including water quality degradation, loss of biodiversity and natural habitats, reduced climate mitigation as well as social and health risks. This study evaluated the effect of different land use types on nutrient stock distribution across varying soil depths in Busega wetland. The soil samples were collected in three different land uses (annually cultivated areas, perennially cultivated areas, and the undisturbed wetland area) at three different depths (0 - 10 cm, 10 - 20 cm, and 20 - 30 cm) in 2021. The soil samples were analyzed for physicochemical soil properties including soil texture and nitrogen, phosphorus, calcium, and potassium concentrations. The interaction between land use type and soil depth did not have a significant effect on nutrient distribution. However, our results showed that the main effects of land use type and soil depth influenced nutrient stock distribution across the wetland. Higher nutrient concentrations were observed under perennial cropping system than in both annual cropping system and the undisturbed wetland area. Soils under perennial cropping systems had the highest soil organic matter (1.45%), calcium (2.06 Cmol/Kg) and potassium (0.091 Cmol/Kg) levels. Higher soil organic matter (1.40%), nitrogen (0.22%), calcium (1.74 Cmol/Kg), and potassium (0.07 Cmol/Kg) were found at the mid-soil depth of 10 - 20 cm. Our results show substantial nutrient changes due to agricultural activities in the Busega wetland, suggesting further research is urgently needed to determine if these changes have adverse effects on biodiversity and water quality of the wetland and nearby water resources. 展开更多
关键词 Annual Cropping System Perennial Cropping System Undisturbed Wetland Area Wetland Encroachment Wetland Degradation
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Fault-Tolerant Control of the Piston Position via Pressure Sensor and Its Estimation for Mini Motion Package of Electro-Hydraulic Actuator
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作者 Huy Q.Tran Tan Nguyen Van Cheolkeun Ha 《Computers, Materials & Continua》 2025年第10期1053-1072,共20页
Hydraulic-electric systems are widely utilized in various applications.However,over time,these systems may encounter random faults such as loose cables,ambient environmental noise,or sensor aging,leading to inaccurate... Hydraulic-electric systems are widely utilized in various applications.However,over time,these systems may encounter random faults such as loose cables,ambient environmental noise,or sensor aging,leading to inaccurate sensor readings.These faults may result in system instability or compromise safety.In this paper,we propose a fault compensation control system to mitigate the effects of sensor faults and ensure system safety.Specifically,we utilize the pressure sensor within the system to implement the control process and evaluate performance based on the piston position.First,we develop a mathematical model to identify optimal parameters for the fault estimation model based on the Lyapunov stability principle.Next,we design an unknown input observer that estimates the state vector and detects pressure sensor faults using a linear matrix inequality optimization algorithm.The estimated pressure faults are incorporated into the fault compensation control system to counteract their effects via a fault residual coefficient.The discrepancy between the feedback state and the estimated state determines this coefficient.We assess the piston position’s performance through pressure control to evaluate the proposed model’s effectiveness.Finally,the system simulation results are analyzed to validate the efficiency of the proposed model.When a pressure sensor fault occurs,the proposed approach effectively minimizes position control errors,enhancing overall system stability.When a pressure sensor fault occurs,the proposed model compensates for the fault to mitigate the impact of pressure problem,thereby enhancing the position control quality of the EHA system.The fault compensation method ensures over 90%system performance,with its effectiveness becoming more evident under pressure sensor faults. 展开更多
关键词 Fault-tolerant control fault estimation unknown input observer electro-hydraulic actuator
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Performance vs.Complexity Comparative Analysis of Multimodal Bilinear Pooling Fusion Approaches for Deep Learning-Based Visual Arabic-Question Answering Systems
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作者 Sarah M.Kamel Mai A.Fadel +1 位作者 Lamiaa Elrefaei Shimaa I.Hassan 《Computer Modeling in Engineering & Sciences》 2025年第4期373-411,共39页
Visual question answering(VQA)is a multimodal task,involving a deep understanding of the image scene and the question’s meaning and capturing the relevant correlations between both modalities to infer the appropriate... Visual question answering(VQA)is a multimodal task,involving a deep understanding of the image scene and the question’s meaning and capturing the relevant correlations between both modalities to infer the appropriate answer.In this paper,we propose a VQA system intended to answer yes/no questions about real-world images,in Arabic.To support a robust VQA system,we work in two directions:(1)Using deep neural networks to semantically represent the given image and question in a fine-grainedmanner,namely ResNet-152 and Gated Recurrent Units(GRU).(2)Studying the role of the utilizedmultimodal bilinear pooling fusion technique in the trade-o.between the model complexity and the overall model performance.Some fusion techniques could significantly increase the model complexity,which seriously limits their applicability for VQA models.So far,there is no evidence of how efficient these multimodal bilinear pooling fusion techniques are for VQA systems dedicated to yes/no questions.Hence,a comparative analysis is conducted between eight bilinear pooling fusion techniques,in terms of their ability to reduce themodel complexity and improve themodel performance in this case of VQA systems.Experiments indicate that these multimodal bilinear pooling fusion techniques have improved the VQA model’s performance,until reaching the best performance of 89.25%.Further,experiments have proven that the number of answers in the developed VQA system is a critical factor that a.ects the effectiveness of these multimodal bilinear pooling techniques in achieving their main objective of reducing the model complexity.The Multimodal Local Perception Bilinear Pooling(MLPB)technique has shown the best balance between the model complexity and its performance,for VQA systems designed to answer yes/no questions. 展开更多
关键词 Arabic-VQA deep learning-based VQA deep multimodal information fusion multimodal representation learning VQA of yes/no questions VQA model complexity VQA model performance performance-complexity trade-off
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Heat Transfer Analysis of Temperature-Sensitive Ternary Nanofluid in MHD and Porous Media Flow:Influence of Volume Fraction and Shape
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作者 Barkilean Jaismitha Jagadeesan Sasikumar +2 位作者 Samad Noeiaghdam Unai Fernandez-Gamiz Thirugnanasambandam Arunkumar 《Frontiers in Heat and Mass Transfer》 2025年第5期1529-1554,共26页
The present study investigates the dynamic behavior of a ternary-hybrid nanofluid within a tapered asymmetric channel,focusing on the impact of unsteady oscillatory flow under the influence of a magnetic field.This st... The present study investigates the dynamic behavior of a ternary-hybrid nanofluid within a tapered asymmetric channel,focusing on the impact of unsteady oscillatory flow under the influence of a magnetic field.This study addresses temperature-sensitive water transport mechanisms relevant to industrial applications such as thermal management and energy-efficient fluid transport.By suspending nanoparticles of diverse shapes-platelets,blades,and spheres in a hybrid base fluid comprising cobalt ferrite,magnesium oxide,and graphene oxide,the study examines the influence of both small and large volume fraction values.The governing equations are converted into a dimensionless form.With suitable assumptions,the partial differential equations(PDEs)are simplified into ordinary differential equations(ODEs),which are then solved using an analyticalmethod.Theproposed solution is verified using a numerical approach with the BVP4C solver.The analysis yields detailed graphs that depict the behavior of key fluid flow parameters,such as velocity,temperature,concentration,skin friction,Nusselt number,and Sherwood number,within the tapered asymmetric channel. 展开更多
关键词 Heat transfer shape factor ternary nanofluid flow TEMPERATURE-DEPENDENT linear slope regression
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Design process of a miniaturized reconfigurable antenna for 5G sub-6 GHz and diverse applications
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作者 Atul Varshney Duygu Nazan Gençoğlan Ahmed Jamal Abdullah Al-Gburi 《Journal of Electronic Science and Technology》 2025年第4期14-31,共18页
This article presents a compact crab-shaped reconfigurable antenna(CSRA)designed for 5G sub-6 GHz wireless applications. The antenna achieves enhanced gain in a miniaturized form factor by incorporating a hexagonal sp... This article presents a compact crab-shaped reconfigurable antenna(CSRA)designed for 5G sub-6 GHz wireless applications. The antenna achieves enhanced gain in a miniaturized form factor by incorporating a hexagonal split-ring structure controlled via two radio frequency(RF) positive-intrinsicnegative(PIN) diodes(BAR64-02V). While the antenna is primarily designed to operate at 3.50 GHz for sub-6 GHz 5G applications, RF switching enables the CSRA to cover a broader frequency spectrum, including the S-band, X-band, and portions of the Ku-band. The proposed antenna offers several advantages: It is low-cost(fabricated on an FR-4 substrate), compact(achieving 64.07% size reduction compared to conventional designs), and features both frequency and gain reconfigurability through digitally controlled PIN diode switching. The reflection coefficients of the antenna, both without diodes and across all four switching states, were experimentally validated in the laboratory using a Keysight Field Fox microwave analyzer(N9916A, 14 GHz). The simulated radiation patterns and gain characteristics closely matched the measured values, demonstrating an excellent agreement. This study bridges the gap between traditional and next-generation antenna designs by offering a compact,cost-effective, and high-performance solution for multiband, reconfigurable wireless communication systems. The integration of double-split-ring resonators and dynamic reconfigurability makes the proposed antenna a strong candidate for various applications, including S-band and X-band systems, as well as the emerging lower 6G band(7.125 GHz–8.400 GHz). 展开更多
关键词 BAR6402V Crab-shaped Gain reconfigurable MINIATURIZATION Sub-6 GHz
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Efficient oxidation of thiosulfate in solution using multistage method
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作者 Hao-ran XU Wei-chao HUANG +4 位作者 A.V.RAVINDRA Duc-lenh PHAN Thi-quynh-xuan LE Li-bo ZHANG Shao-hua YIN 《Transactions of Nonferrous Metals Society of China》 2025年第8期2762-2776,共15页
The oxidation characteristics of sulfite and thiosulfate were examined by using thermodynamic calculations and simulated desulfurization solution experiments to investigate their difference.Subsequently,a new multista... The oxidation characteristics of sulfite and thiosulfate were examined by using thermodynamic calculations and simulated desulfurization solution experiments to investigate their difference.Subsequently,a new multistage oxidation method using oxygen−ammonium persulfate was presented and applied to the oxidation of a real desulfurization solution.The results show that the concentrations of thiosulfate and sulfite in the real desulfurization solution decrease from 48.76 and 61.76 g/L to 2.24 and 0.02 g/L,respectively,and the ammonium sulfate products obtained are white with uniform particles.In addition,compared with ammonium persulfate alone,the multistage oxidation method can reduce the ammonium persulfate addition by 37.56%and treatment cost by 28.13%. 展开更多
关键词 ammonium persulfate OXYGEN THIOSULFATE desulfurization solution COST
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High-thermal free vibration analysis of functionally graded microplates using a new finite element formulation based on TSDT and MSCT
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作者 Huu Trong Dang Nhan Thinh Hoang +2 位作者 Quoc Hoa Pham Trung Thanh Tran Huy Gia Luong 《Defence Technology(防务技术)》 2025年第2期131-149,共19页
Recent advancements in additive manufacturing(AM)have revolutionized the design and production of complex engineering microstructures.Despite these advancements,their mathematical modeling and computational analysis r... Recent advancements in additive manufacturing(AM)have revolutionized the design and production of complex engineering microstructures.Despite these advancements,their mathematical modeling and computational analysis remain significant challenges.This research aims to develop an effective computational method for analyzing the free vibration of functionally graded(FG)microplates under high temperatures while resting on a Pasternak foundation(PF).This formulation leverages a new thirdorder shear deformation theory(new TSDT)for improved accuracy without requiring shear correction factors.Additionally,the modified couple stress theory(MCST)is incorporated to account for sizedependent effects in microplates.The PF is characterized by two parameters including spring stiffness(k_(w))and shear layer stiffness(k_(s)).To validate the proposed method,the results obtained are compared with those of the existing literature.Furthermore,numerical examples explore the influence of various factors on the high-temperature free vibration of FG microplates.These factors include the length scale parameter(l),geometric dimensions,material properties,and the presence of the elastic foundation.The findings significantly enhance our comprehension of the free vibration of FG microplates in high thermal environments.In addition,the findings significantly enhance our comprehension of the free vibration of FG microplates in high thermal environments.In addition,the results of this research will have great potential in military and defense applications such as components of submarines,fighter aircraft,and missiles. 展开更多
关键词 Microplates Functionally graded material Finite element method Modified couple stress theory New TSDT High-thermal free vibration Pasternak foundation
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Classification and Age Estimation of Fossil Shells from Ban Sap Noi Geopark in Thailand,through the Material Characterization Techniques
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作者 Sirikorn Pongtornkulpanich Patcharin Naemchanthara +3 位作者 Kridsada Faksawat Weeranut Kaewwiset Pichet Limsuwan Kittisakchai Naemchanthara 《Journal of Wuhan University of Technology(Materials Science)》 2025年第3期635-643,共9页
The fossil shells on the sedimentary rocks were collected from The Historical Park,Ban Sap Noi Geopark,Phetchabun Province,Thailand.However,the fossils remained in this area were investigated on the characteristic spe... The fossil shells on the sedimentary rocks were collected from The Historical Park,Ban Sap Noi Geopark,Phetchabun Province,Thailand.However,the fossils remained in this area were investigated on the characteristic species only in geological studies with taxonomy for fossil age predicting.To fill up the gap of these studies,the material characterization techniques were used to study the chemical composition and structure of fossil shells I,II and III.The results clearly showed that the morphologies of all fossil shells were Brachiopod fossils with different species.The functional group and elemental composition of all fossil shells showed that the high content of calcium carbonate was a major composition.In addition,the high content of quartz indicated the silica precipitation phenomenon in all fossil shells.The element composition of cross-sectional morphology and energy dispersive spectroscope (EDS mapping) were used to confirm the presence of Si element in each zone of fossil shells.The crystal structures of all fossil shells were investigated and indicated that the calcium carbonate compound was a calcite phase and silicon dioxide compound was a quartz phase.Moreover,the crystal structure of quartz phase was used to calculate the crystallinity index.The crystallinity index values in all fossil shells indicated a well-crystallized quartz.The age of fossil shells was estimated and found to be brachiopod fossil in carboniferous period with the age of about 359.2 to 299.0 million years. 展开更多
关键词 fossil shell Ban Sap Noi Geopark crystallinity index fossil age carboniferous period
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