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Absorption and Structural Property of Ethanol/Water Mixture with Carbon Nanotubes
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作者 杜生平 赵文辉 袁岚峰 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第4期487-493,I0004,共8页
Molecular dynamics (MD) simulations are performed to study the structure and adsorption of ethanol/water mixture within carbon nanotubes (CNTs). Inside the (6,6) and (10,10) CNTs, there are always almost full ... Molecular dynamics (MD) simulations are performed to study the structure and adsorption of ethanol/water mixture within carbon nanotubes (CNTs). Inside the (6,6) and (10,10) CNTs, there are always almost full of ethanol molecules and hardly water molecules. Inside wider CNTs, there are some water molecules, while the ethanol mass fractions inside the CNTs are still much higher than the corresponding bulk values. A series of structural analysis for the molecules inside and outside the CNTs are performed, including the distributions of radial, axial, angular density, orientation, and the number of hydrogen bonds. The angular density distribution of the molecules in the first solvation shell outside the CNTs indicates that the methyl groups of ethanol molecules have the strongest interaction with the carbon wall, and are pinned to the centers of the hexagons of the CNTs. Based on the understanding of the microscopic mechanism of these phenomena, we propose that the CNTs prefer to contain ethanol rather than methanol. 展开更多
关键词 ethanol/water Carbon nanotube Adsorption Molecular dynamics simulation
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Molecular simulation of penetration separation for ethanol/water mixtures using two-dimensional nanoweb graphynes 被引量:1
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作者 Wei Zhang Zhijun Xu Xiaoning Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第2期286-292,共7页
Graphyne is expected to be a new-class of highly-efficient sieving membranes due to its controllable uniform pore structure and ultrathin single-atom thickness. Herein, we computationally investigate the permeation pe... Graphyne is expected to be a new-class of highly-efficient sieving membranes due to its controllable uniform pore structure and ultrathin single-atom thickness. Herein, we computationally investigate the permeation performance of liquid ethanol–water mixtures across polyporous two-dimensional γ-graphyne sheets. It was found that, in the mixture, ethanol with larger molecular diameter permeates faster through the graphyne pores than water. The simulations demonstrate that pristine graphynes could act as highly-efficient ethanol-permselective membranes for separation of ethanol–water mixtures, with ethanol permeability remarkably higher than conventional membranes. This separation mechanism is distinctly different from the molecular-size dependent sieving process. The stronger hydrophobic interfacial affinity between graphyne and ethanol makes ethanol molecules preferentially adsorb on graphyne surface and selectively penetrate through graphyne pores. This penetration mechanism provides new understanding of molecular transport through atomically thick two-dimensional nanoporous membranes and this work is expected to be valuable in the potential development of highly-efficient membranes for liquid-phase mixture separation. 展开更多
关键词 Graphynes MEMBRANE SEPARATION ethanol/water MOLECULAR simulation
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PERVAPORATION OF ETHANOL/WATER MIXTURES WITH HIGH FLUX BY ZEOLITE-FILLED PDMS/PVDF COMPOSITE MEMBRANES 被引量:5
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作者 李继定 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2009年第6期771-780,共10页
Thin-film zeolite-filled silicone/PVDF composite membranes were fabricated by incorporating zeolite particles into PDMS(poly(dimethylsiloxane)) membranes.The morphology of zeolite particles and zeolite filled silicone... Thin-film zeolite-filled silicone/PVDF composite membranes were fabricated by incorporating zeolite particles into PDMS(poly(dimethylsiloxane)) membranes.The morphology of zeolite particles and zeolite filled silicone composite membranes were characterized by SEM.The zeolite-filled PDMS/PVDF composite membranes were applied for the pervaporation of ethanol/water mixtures and showed higher flux compared with that reported in literatures.The effect of zeolite loading and Si/Al ratio of zeolite particles on pe... 展开更多
关键词 ZEOLITE PDMS High flux PERVAPORATION ethanol recovery
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Fabrication and Characterization of Pulp/Chitosan Composite Membranes Crosslinked with 3-Methylglutaric Anhydride for Pervaporation of Ethanol/Water Mixture 被引量:2
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作者 Truong Thi Cam Trang Nguyen Thi Nhung Takaomi Kobayashi 《Engineering(科研)》 2011年第2期110-118,共9页
Chitosan/Cellulose (CTS/CL) composite membranes were prepared by cross-linking reaction with 3-methy- lglutaric anhydride (3MGA). The cross-linked membranes with CTS/CL were obtained at different CTS con- tents in var... Chitosan/Cellulose (CTS/CL) composite membranes were prepared by cross-linking reaction with 3-methy- lglutaric anhydride (3MGA). The cross-linked membranes with CTS/CL were obtained at different CTS con- tents in variations from 50 to 100 wt%, and these membranes were applied in the dehydration of ethanol/wa- ter mixtures. Especially, it was observed that in the case of a composite membrane containing chitosan 80% (CTS/CL-80/20) showed a performance with a separation factor of α = 17.1 and a total permeation flux of J = 326 g/(m2h). It was observed that the total permeation flux decreased when the cross-linking increased and the increase in the ethanol content in the feed solution showed an increase in the separation factor. The CTS/ CL-80/20 showed excellent performance with good mechanical strength and dehydration performance in the ethanol/water mixture separation. 展开更多
关键词 PERVAPORATION Chitosan CELLULOSE Contact Angle ethanol Composite Membrane
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Validation of a Method for Characterization of Ethanol in Water by HS-GC-FID to Serve the Traceability of Halal Measurements
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作者 Adel B. Shehata Abdulrahman R. Al Askar +3 位作者 Mohammed A. Al Rasheed Abdulrahman M. Al Zahrany Fahd A. Al Kharraa Sowailem A. Al Sowailem 《Green and Sustainable Chemistry》 2024年第2期17-28,共12页
The determination of the ethanol content in food products is of fundamental importance for HALAL certification. In this work, an analytical method for the determination of ethanol in water by headspace gas chromatogra... The determination of the ethanol content in food products is of fundamental importance for HALAL certification. In this work, an analytical method for the determination of ethanol in water by headspace gas chromatography with flame ionization detector (HS-GC-FID) has been developed and validated for the use in characterization of ethanol reference materials. The validation study was carried out in the linear calibration range 100 - 1500 mg/kg using the NIST SRM 2900, nominal 95.6%. The studied performance characteristics of the method were the limit of detection, LOD, the limit of quantification LOQ, selectivity, linearity, precision, recovery and bias. The validation results showed that the method is selective, precise, accurate and free from any significant bias. The LOD and LOQ were 1.27 and 3.86 mg/kg respectively and the estimated expanded uncertainty was 2% indicating that the method is fit for the purpose of certification of ethanol in water reference materials. 展开更多
关键词 ethanol HS-GC-FID VALIDATION LINEARITY Precision Bias
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Comparative Analysis: Trays versus Packed Columns in Pressure-Swing Distillation for the Separation of Tetrahydrofuran, Water and Ethanol Azeotropic Mixture
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作者 Samuel Oluwaseun Ogunrinde Tolulope Daniel Adekoya Thomas A. Orhadahwe 《World Journal of Engineering and Technology》 2024年第3期798-819,共22页
This paper delves into the comparative study of tray and packed column pressure swing distillation systems, focusing on the separation of a ternary mixture containing ethanol, tetrahydrofuran (THF), and water. The stu... This paper delves into the comparative study of tray and packed column pressure swing distillation systems, focusing on the separation of a ternary mixture containing ethanol, tetrahydrofuran (THF), and water. The study particularly emphasizes the production of 99.5 w/w% tetrahydrofuran from the downstream product of 1,4-butanediol synthesis via diethyl maleate. Pro/II simulation software is utilized to explore various system configurations, including sieve trays, valve trays, and packed columns. Material and energy balances are performed to ascertain stream compositions and energy demands. The investigation encompasses the effects of column operating pressure on condenser and reboiler temperatures, as well as the implications of utility streams. A rigorous distillation model is employed to compare valve tray, sieve tray, and random packing (utilizing Norton Super Intalox) column designs by varying the number of trays, reflux ratio, and second distillation column pressure. Heat exchangers are integrated into the model, and their areas and utility flow rates are computed and integrated into the economic assessment. Economic analysis, guided by Net Present Value (NPV) calculations over a 20-year span, drives the selection of the most cost-effective design. Results demonstrate that while all designs are energy-efficient, the packed column system emerges as the most economical choice, offering a comprehensive framework for the separation process. Furthermore, optimal design configurations and operating conditions for both tray and packed column systems are outlined, providing valuable insights for industrial applications. 展开更多
关键词 Azetrope TETRAHYDROFURAN ethanol Pressure-Swing DISTILLATION Simulation
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Pt nanoclusters modified porous g-C_(3)N_(4)nanosheets to significantly enhance hydrogen production by photocatalytic water reforming of methanol
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作者 Yi-Fei Liang Jin-Rong Lu +2 位作者 Shang-Kun Tian Wen-Quan Cui Li Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期40-50,共11页
For the use of green hydrogen energy,it is crucial to have efficient photocatalytic activity for hydrogen generation by water reforming of methanol under mild conditions.Much attention has been paid to gC_(3)N_(4)as a... For the use of green hydrogen energy,it is crucial to have efficient photocatalytic activity for hydrogen generation by water reforming of methanol under mild conditions.Much attention has been paid to gC_(3)N_(4)as a promising photocatalyst for the generation of hydrogen.To improve the separation of photogenerated charge,porous nanosheet g-C_(3)N_(4)was modified with Pt nanoclusters(Pt/g-C_(3)N_(4))through impregnation and following photo-induced reduction.This catalyst showed excellent photocatalytic activity of water reforming of methanol fo r hydrogen production with a 17.12 mmol·g^(-1)·h^(-1)rate at room temperature,which was 311 times higher than that of the unmodified g-C_(3)N_(4).The strong interactions of Pt-N in Pt/g-C_(3)N_(4)constructed effective electron transfer channels to promote the separation of photogenerated electrons and holes effectively.In addition,in-situ infrared spectroscopy was used to investigate the intermediates of the hydrogen production reaction,which proved that methanol and water eventually turn into H_(2)and CO_(2)via formaldehyde and formate.This study provides insights for understanding the photocatalytic hydrogen production in the water reforming of methanol. 展开更多
关键词 water reforming of methanol Photocatalysis g-C_(3)N_(4) Pt nanoclusters Hydrogen production
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Bimetallic Single‑Atom Catalysts for Water Splitting
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作者 Megha A.Deshmukh Aristides Bakandritsos Radek Zbořil 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期1-45,共45页
Green hydrogen from water splitting has emerged as a critical energy vector with the potential to spearhead the global transition to a fossil fuel-independent society.The field of catalysis has been revolutionized by ... Green hydrogen from water splitting has emerged as a critical energy vector with the potential to spearhead the global transition to a fossil fuel-independent society.The field of catalysis has been revolutionized by single-atom catalysts(SACs),which exhibit unique and intricate interactions between atomically dispersed metal atoms and their supports.Recently,bimetallic SACs(bimSACs)have garnered significant attention for leveraging the synergistic functions of two metal ions coordinated on appropriately designed supports.BimSACs offer an avenue for rich metal–metal and metal–support cooperativity,potentially addressing current limitations of SACs in effectively furnishing transformations which involve synchronous proton–electron exchanges,substrate activation with reversible redox cycles,simultaneous multi-electron transfer,regulation of spin states,tuning of electronic properties,and cyclic transition states with low activation energies.This review aims to encapsulate the growing advancements in bimSACs,with an emphasis on their pivotal role in hydrogen generation via water splitting.We subsequently delve into advanced experimental methodologies for the elaborate characterization of SACs,elucidate their electronic properties,and discuss their local coordination environment.Overall,we present comprehensive discussion on the deployment of bimSACs in both hydrogen evolution reaction and oxygen evolution reaction,the two half-reactions of the water electrolysis process. 展开更多
关键词 Single-atom catalysts Single-atom dimers Hydrogen evolution Oxygen evolution water splitting
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The emerging role of mesenchymal stem cell-derived extracellular vesicles to ameliorate hippocampal NLRP3 inflammation induced by binge-like ethanol treatment in adolescence
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作者 Susana Mellado María JoséMorillo-Bargues +4 位作者 Carla Perpiñá-Clérigues Francisco García-García Victoria Moreno-Manzano Consuelo Guerri María Pascual 《Neural Regeneration Research》 SCIE CAS 2025年第4期1153-1163,共11页
Our previous studies have reported that activation of the NLRP3(NOD-,LRR-and pyrin domain-containing protein 3)-inflammasome complex in ethanol-treated astrocytes and chronic alcohol-fed mice could be associated with ... Our previous studies have reported that activation of the NLRP3(NOD-,LRR-and pyrin domain-containing protein 3)-inflammasome complex in ethanol-treated astrocytes and chronic alcohol-fed mice could be associated with neuroinflammation and brain damage.Mesenchymal stem cell-derived extracellular vesicles(MSC-EVs)have been shown to restore the neuroinflammatory response,along with myelin and synaptic structural alterations in the prefrontal cortex,and alleviate cognitive and memory dysfunctions induced by binge-like ethanol treatment in adolescent mice.Considering the therapeutic role of the molecules contained in mesenchymal stem cell-derived extracellular vesicles,the present study analyzed whether the administration of mesenchymal stem cell-derived extracellular vesicles isolated from adipose tissue,which inhibited the activation of the NLRP3 inflammasome,was capable of reducing hippocampal neuroinflammation in adolescent mice treated with binge drinking.We demonstrated that the administration of mesenchymal stem cell-derived extracellular vesicles ameliorated the activation of the hippocampal NLRP3 inflammasome complex and other NLRs inflammasomes(e.g.,pyrin domain-containing 1,caspase recruitment domain-containing 4,and absent in melanoma 2,as well as the alterations in inflammatory genes(interleukin-1β,interleukin-18,inducible nitric oxide synthase,nuclear factor-kappa B,monocyte chemoattractant protein-1,and C–X3–C motif chemokine ligand 1)and miRNAs(miR-21a-5p,miR-146a-5p,and miR-141-5p)induced by binge-like ethanol treatment in adolescent mice.Bioinformatic analysis further revealed the involvement of miR-21a-5p and miR-146a-5p with inflammatory target genes and NOD-like receptor signaling pathways.Taken together,these findings provide novel evidence of the therapeutic potential of MSC-derived EVs to ameliorate the hippocampal neuroinflammatory response associated with NLRP3 inflammasome activation induced by binge drinking in adolescence. 展开更多
关键词 ADOLESCENCE binge-like ethanol treatment extracellular vesicles hippocampus mesenchymal stem cells neuroinflammation NOD- LRR-and pyrin domain-containing protein 3(NLRP3)
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Pretreatment with nano-silver extends the post-harvest longevity of gladiolus cut flowers by reducing free water mobility
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作者 Xiumei Li Qinjian Liu +5 位作者 Hongbo Li Yuanyuan Chen Zhongjian Chen Shenggen He Jun Liu Shijuan Yan 《Horticultural Plant Journal》 2025年第1期377-388,共12页
The water content of cut flowers is a significant factor in their post-harvest quality.In this study,we examine the efficacy of silver nanoparticles(NS)on the longevity of cut gladiolus,with a focus on water state and... The water content of cut flowers is a significant factor in their post-harvest quality.In this study,we examine the efficacy of silver nanoparticles(NS)on the longevity of cut gladiolus,with a focus on water state and distribution.We used Low-field nuclear magnetic resonance(LF-NMR)technology to identify three water fractions with different transverse relaxation times(T2)values:bound water T21(<10 ms),intermediate immobilized water T22(10-100 ms),and the slowest component free water T23(>10 ms).During the opening process,T23increased at stages 2 and 3 and then decreased,T22 decreased slowly,and T21 remained unchanged.Free water values were consistently higher than bound water and immobilized water and reached their maximum from stage 2 until stage 4,when the petals were extended and began to wilt.The vascular bundles responsible for transporting water had higher water content,as detected by proton density-weighted magnetic resonance imaging(MRI).Bound water and free water with NS pretreatments in bracts were initially lower but then two days later the signal amplitude of each water state exceeded those of the control,indicating that the treatment enhanced the water-holding capacity over time.Furthermore,NS pretreatments reduced the free water mobility of the cut flowers and inhibited stem decay.Additionally,we found that NS can enter the stem and are primarily transported upward along the xylem with water using scanning electron microscopy(SEM)and energy-dispersive X-ray spectroscopy(EDS)technology.Overall,our findings indicate that NS pretreatment reduces free water in gladiolus cut flowers,enhancing their water retention and prolonging their vase life. 展开更多
关键词 water state Nanoparticles Vase life Nuclear magnetic resonance Cut flowers
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Stable nanobubbles on ordered water monolayer near ionic model surfaces
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作者 Luyao Huang Cheng Ling +6 位作者 Limin Zhou Wenlong Liang Yujie Huang Lijuan Zhang Phornphimon Maitarad Dengsong Zhang Chunlei Wang 《Chinese Physics B》 2025年第1期143-148,共6页
The stable nanobubbles adhered to mineral surfaces may facilitate their efficient separation via flotation in the mining industry.However,the state of nanobubbles on mineral solid surfaces is still elusive.In this stu... The stable nanobubbles adhered to mineral surfaces may facilitate their efficient separation via flotation in the mining industry.However,the state of nanobubbles on mineral solid surfaces is still elusive.In this study,molecular dynamics(MD)simulations are employed to examine mineral-like model surfaces with varying degrees of hydrophobicity,modulated by surface charges,to elucidate the adsorption behavior of nanobubbles at the interface.Our findings not only contribute to the fundamental understanding of nanobubbles but also have potential applications in the mining industry.We observed that as the surface charge increases,the contact angle of the nanobubbles increases accordingly with shape transformation from a pancake-like gas film to a cap-like shape,and ultimately forming a stable nanobubble upon an ordered water monolayer.When the solid–water interactions are weak with a small partial charge,the hydrophobic gas(N_(2))molecules accumulate near the solid surfaces.However,we have found,for the first time,that gas molecules assemble a nanobubble on the water monolayer adjacent to the solid surfaces with large partial charges.Such phenomena are attributed to the formation of a hydrophobic water monolayer with a hydrogen bond network structure near the surface. 展开更多
关键词 NANOBUBBLES molecular dynamic simulation ordered water monolayer hydrogen bond network
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Impact of Land Use Change on Ecosystem Services Values in Danjiangkou Reservoir Area,China in the Context of National Water Network Project Construction
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作者 LIU Linghua ZHENG Liang +3 位作者 WANG Ying LIU Chongchong ZHANG Bowen BI Yuzhe 《Chinese Geographical Science》 2025年第1期111-130,共20页
Investigating the ecological impact of land use change in the context of the construction of national water network project is crucial,as it is imperative for achieving the sustainable development goals of the nationa... Investigating the ecological impact of land use change in the context of the construction of national water network project is crucial,as it is imperative for achieving the sustainable development goals of the national water network and guaranteeing regional ecological stability.Using the Danjiangkou Reservoir Area(DRA),China as the study area,this paper first examined the spatiotemporal dynamics of natural landscape patterns and ecosystem service values(ESV)in the DRA from 2000 to 2018 and then investigated the spatial clustering characteristics of the ESV using spatial statistical analysis tools.Finally,the patch-generating land use simulation(PLUS)model was used to simulate the natural landscape and future changes in the ESV of the DRA from 2018 to 2028 under four different development scenarios:business as usual(BAU),economic development(ED),ecological protection(EP),and shoreline protection(SP).The results show that:during 2000-2018,the construction of water facilities had a significant impact on regional land use/land cover(LULC)change,with a 24830 ha increase in watershed area.ESV exhibited an increasing trend,with a significant and growing spatial clustering effect.The transformation of farmland to water bodies led to accelerated ESV growth,while the transformation of forest land to farmland led to a decrease in the ESV.Normalized difference vegetation index(NDVI)had the strongest effect on the ESV.ESV exhibited a continuous increase from 2018 to 2028 under all the simulation scenarios.The EP scenario had the greatest increase in ESV,while the ED scenario had the smallest increase.The findings suggest that projected land use patterns under different scenarios have varied impacts on ecosystem services(ESs)and that the management and planning of the DRA should balance social,economic,ecological,and security benefits.nomic,ecological,and security benefits. 展开更多
关键词 ecosystem services value(ESV) national water network project of China South-to-North water Diversion Project(SNWDP)of China multi-scenario simulation Danjiangkou Reservoir Area China
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Water Quality,Influential Factors,and Management Strategies from 2016 to 2020 in the Yangtze River Economic Belt,China
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作者 LIN Lanyu GUO Congrong +6 位作者 CHEN Yanan HE Lihuan YAN Luyu FANG Dekun MA Guangwen ZHANG Fengying LI Mingsheng 《Chinese Geographical Science》 2025年第1期175-186,共12页
The Yangtze River economic belt(YREB),China is important to the Chinese economy and for supporting sustainable development.Clarifying the relationship between water quality indices and socioeconomic indicators could h... The Yangtze River economic belt(YREB),China is important to the Chinese economy and for supporting sustainable development.Clarifying the relationship between water quality indices and socioeconomic indicators could help improve aquatic environment management in the YREB and our understanding of the causes and effects of water quality variations in other large river basins.In this study,river water quality,factors affecting water quality,and management strategies,and correlations between water quality indices and socioeconomic indicators in the YREB during the 13th Five-Year Plan period(2016-2020)were assessed.The single-factor evaluation method,constant price for GDP,and correlation analyses were adopted.The results showed that:1)water quality in the YREB improved during the 13th Five-Year Plan period.The number of aquatic environment sections meeting GradeⅠ-Ⅲwater quality standards increased by 13.1%and the number below Grade V decreased by 2.9%.2)The values of 12 indicators in the YREB exceeded relevant standards.The indicators with highest concentreation were the total phosphorus,chemical oxygen demand,ammonia nitrogen,and permanganate index,which were relatively high in downstream regions in Anhui Province,Jiangsu Province,and Shanghai Municipality.3)Ammonia nitrogen,chemical oxygen demand,and total phosphorus emissions per unit area and water extraction per unit area are relatively high in the three downstream regions mentioned above.4)Increased domestic sewage discharges have increased total wastewater discharges in the YREB.5)River water quality in the YREB strongly correlated with population,economic,and water resource indices and less strongly correlated with government investment,agriculture,meteorology,energy,and forestry indices.This confirmed the need to decrease wastewater discharges and non-point-source pollutant emissions.The aquatic environment could be improved by taking reasonable measures to control population growth,adjusting the industrial structure to accelerate industrial transformation and increase the proportion of tertiary industries,and investing in technological innovations to protect the environment. 展开更多
关键词 water quality FACTORS coping strategies Yangtze River economic belt(YREB) China
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An extended discontinuous deformation analysis for simulation of grouting reinforcement in a water-rich fractured rock tunnel
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作者 Jingyao Gao Siyu Peng +1 位作者 Guangqi Chen Hongyun Fan 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第1期168-186,共19页
Grouting has been the most effective approach to mitigate water inrush disasters in underground engineering due to its ability to plug groundwater and enhance rock strength.Nevertheless,there is a lack of potent numer... Grouting has been the most effective approach to mitigate water inrush disasters in underground engineering due to its ability to plug groundwater and enhance rock strength.Nevertheless,there is a lack of potent numerical tools for assessing the grouting effectiveness in water-rich fractured strata.In this study,the hydro-mechanical coupled discontinuous deformation analysis(HM-DDA)is inaugurally extended to simulate the grouting process in a water-rich discrete fracture network(DFN),including the slurry migration,fracture dilation,water plugging in a seepage field,and joint reinforcement after coagulation.To validate the capabilities of the developed method,several numerical examples are conducted incorporating the Newtonian fluid and Bingham slurry.The simulation results closely align with the analytical solutions.Additionally,a set of compression tests is conducted on the fresh and grouted rock specimens to verify the reinforcement method and calibrate the rational properties of reinforced joints.An engineering-scale model based on a real water inrush case of the Yonglian tunnel in a water-rich fractured zone has been established.The model demonstrates the effectiveness of grouting reinforcement in mitigating water inrush disaster.The results indicate that increased grouting pressure greatly affects the regulation of water outflow from the tunnel face and the prevention of rock detachment face after excavation. 展开更多
关键词 Discontinuous deformation analysis(DDA) water-rich fractured rock tunnel Grouting reinforcement water inrush disaster
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Enhancing Evapotranspiration Estimation: A Bibliometric and Systematic Review of Hybrid Neural Networks in Water Resource Management
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作者 Moein Tosan Mohammad Reza Gharib +1 位作者 Nasrin Fathollahzadeh Attar Ali Maroosi 《Computer Modeling in Engineering & Sciences》 2025年第2期1109-1154,共46页
Accurate estimation of evapotranspiration(ET)is crucial for efficient water resource management,particularly in the face of climate change and increasing water scarcity.This study performs a bibliometric analysis of 3... Accurate estimation of evapotranspiration(ET)is crucial for efficient water resource management,particularly in the face of climate change and increasing water scarcity.This study performs a bibliometric analysis of 352 articles and a systematic review of 35 peer-reviewed papers,selected according to PRISMA guidelines,to evaluate the performance of Hybrid Artificial Neural Networks(HANNs)in ET estimation.The findings demonstrate that HANNs,particularly those combining Multilayer Perceptrons(MLPs),Recurrent Neural Networks(RNNs),and Convolutional Neural Networks(CNNs),are highly effective in capturing the complex nonlinear relationships and tem-poral dependencies characteristic of hydrological processes.These hybrid models,often integrated with optimization algorithms and fuzzy logic frameworks,significantly improve the predictive accuracy and generalization capabilities of ET estimation.The growing adoption of advanced evaluation metrics,such as Kling-Gupta Efficiency(KGE)and Taylor Diagrams,highlights the increasing demand for more robust performance assessments beyond traditional methods.Despite the promising results,challenges remain,particularly regarding model interpretability,computational efficiency,and data scarcity.Future research should prioritize the integration of interpretability techniques,such as attention mechanisms,Local Interpretable Model-Agnostic Explanations(LIME),and feature importance analysis,to enhance model transparency and foster stakeholder trust.Additionally,improving HANN models’scalability and computational efficiency is crucial,especially for large-scale,real-world applications.Approaches such as transfer learning,parallel processing,and hyperparameter optimization will be essential in overcoming these challenges.This study underscores the transformative potential of HANN models for precise ET estimation,particularly in water-scarce and climate-vulnerable regions.By integrating CNNs for automatic feature extraction and leveraging hybrid architectures,HANNs offer considerable advantages for optimizing water management,particularly agriculture.Addressing challenges related to interpretability and scalability will be vital to ensuring the widespread deployment and operational success of HANNs in global water resource management. 展开更多
关键词 Artificial neural networks bibliometric analysis EVAPOTRANSPIRATION hybrid models research trends systematic literature review water resources management
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Research hotspot and trend of plant water use in karst: Based on a bibliometric analysis from 1984 to 2022
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作者 De-gen Zhu Jing Ning +5 位作者 Hui Yang Jun-bing Pu Jian-hua Cao Meng-xia Zhou Mitja Prelovsek Natasa Ravbar 《China Geology》 2025年第1期214-229,共16页
Research on the ecohydrological processes of terrestrial plants is a frontier field comprising ecology,hydrology and global change research,yielding the key theoretical foundations of ecohydrology.In karst areas,due t... Research on the ecohydrological processes of terrestrial plants is a frontier field comprising ecology,hydrology and global change research,yielding the key theoretical foundations of ecohydrology.In karst areas,due to its unique geological background,the karst landscape is strongly developed,with high bedrock exposure,high permeability,fragmented soils,shallow soils,and high spatial heterogeneity,resulting in very limited water storage for plant uptake and growth in rock fissures and shallow soils.Therefore,water conditions are an important ecological factor influencing plant growth.To comprehensively understand the current progress and development trends in plant water use research focusing on karst areas,this paper uses the VOSviewer software to analyze the literature on plant water use in karst areas between 1984 and 2022.The results showed that:(1)Research on plant water use in karst areas has developed rapidly worldwide,and the number of relevant studies in the literature have increased year by year,which together means that it is attracting more and more attention.(2)The investigation of plant water sources,geological background of karst areas,seasonal arid tropical climates,the relationship betweenδ13C values and plant water use efficiency,karst plant water use in karst savannas and subtropical areas,and ecosystems under climate change yields the knowledge base in this field.(3)Most studies in this area focus on the division of water sources of plants in karst areas,the methods of studying the water use sources of plants,and the water use strategies and efficiency of plants.(4)Future research will focus on how plant water use in karst areas is influenced by Earth’s critical zones,climate change,and ecohydrological separation.These studies will provide a key scientific basis for guiding ecological restoration and promoting sustainable development in karst areas. 展开更多
关键词 Terrestrial plants Plant water use Karst area Climate change ECOHYDROLOGY BIBLIOMETRICS Ecological restoration Sustainable development Environmental restoration engineering Web of Science
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Mechanism of ethanol/water reverse separation through a functional graphene membrane:a molecular simulation investigation 被引量:1
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作者 Quan Liu Xian Wang +2 位作者 Yanan Guo Gongping Liu Kai-Ge Zhou 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2023年第3期347-357,共11页
Reverse-selective membranes have attracted considerable interest for bioethanol production.However,to date,the reverse-separation performance of ethanol/water is poor and the separation mechanism is unclear.Graphene-b... Reverse-selective membranes have attracted considerable interest for bioethanol production.However,to date,the reverse-separation performance of ethanol/water is poor and the separation mechanism is unclear.Graphene-based membranes with tunable apertures and functional groups have shown substantial potential for use in molecular separation.Using molecular dynamics simulations,for the first time,we reveal twoway selectivity in ethanol/water separation through functional graphene membranes.Pristine graphene(PG)exhibits reverse-selective behavior with higher ethanol fluxes than water,resulting from the preferential adsorption for ethanol.Color flow mappings show that this ethanol-permselective process is initiated by the presence of ethanol-enriched and water-barren pores;this has not been reported in previous studies.In contrast,water molecules are preferred for hydroxylated graphene membranes because of the synergistic effects of molecular sieving and functional-group attraction.A simulation of the operando condition shows that the PG membrane with an aperture size of 3.8Åachieves good separation performance,with an ethanol/water separation factor of 34 and a flux value of 69.3 kg∙m‒2∙h‒1∙bar‒1.This study provides new insights into the reverse-selective mechanism of porous graphene membranes and a new avenue for efficient biofuel production. 展开更多
关键词 reverse separation graphene membrane ethanol/water separation molecular simulation
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Distributions and risk assessment of heavy metals in solid waste in lead-zinc mining areas and across the soil, water body, sediment and agricultural product ecosystem in their surrounding areas
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作者 Zhi-qiang Wu Hai-ying Li +3 位作者 Liu-yan Lu Guo-jun Liang Ting-ting Wu Jiang-xia Zhu 《China Geology》 2025年第1期92-106,共15页
To identify the root causes of heavy metal contamination in soils as well as prevent and control such contamination from its sources,this study explored the accumulation patterns and ecological risks of heavy metals l... To identify the root causes of heavy metal contamination in soils as well as prevent and control such contamination from its sources,this study explored the accumulation patterns and ecological risks of heavy metals like Cd and Pb in solid waste in mining areas and across the water body,sediment,soil and agricultural product ecosystem surrounding the mining areas.Focusing on the residual solid waste samples in lead-zinc deposits in a certain area of Guizhou Province,along with samples of topsoils,irrigation water,river sediments,and crops from surrounding areas.This study analyzed the distributions of eight heavy metals,i.e.,Cd,As,Cr,Hg,Pb,Zn,Cu,and Ni,in the samples through field surveys and sample tests.Furthermore,this study assessed the contamination levels and ecological risks of heavy metals in soils,sediments,and agricultural products using methods such as the single-factor index,Nemerow composite index,and potential ecological risk assessment.The results indicate that heavy metals in the solid waste samples all exhibited concentrations exceeding their risk screening values,with 60%greater than their risk intervention values.The soils and sediments demonstrate slight and moderate comprehensive ecological risks of heavy metals.The single-factor potential ecological risks of heavy metals in both the soil and sediment samples decreased in the order of Hg,Cd,Pb,As,Cu,Zn,Cr,and Ni,suggesting the same sources of heavy metals in the soils and sediments.Most of the agricultural product samples exhibited over-limit concentrations of heavy metals dominated by Cd,Pb,Ni,and Cr,excluding Hg and As.The agricultural product assessment using the Nemerow composite index reveals that 35%of the agricultural product samples reached the heavy metal contamination level,implying that the agricultural products from farmland around the solid waste dumps have been contaminated with heavy metals.The eight heavy metals in the soil,sediment,and agricultural product samples manifested high coefficients of variation(CVs),indicating pronounced spatial variability.This suggests that their concentrations in soils,sediments,and agricultural products are significantly influenced by human mining activities.Additionally,the agricultural products exhibit strong transport and accumulation capacities for Cd,Cu,and Zn. 展开更多
关键词 Lead-zinc mining area Solid waste SOIL water body SEDIMENT Agricultural product Nemerow composite index Cd Pb Ni Cr elements Heavy metal contamination Ecological risk assessment Coefficients of variation(CVs) Environmental restoration engineering
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VAPOR-LIQUID EQUILIBRIA FOR PROPYLENE -METHANOL-WATER SYSTEM
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作者 陈晓晖 王春艳 +1 位作者 许锡恩 陈宪 《Transactions of Tianjin University》 EI CAS 1999年第1期101-104,共4页
In this article VLE data for a ternary system (propylene-methanol-water) under 30~60 C,0. 3~0. 9 MPa with a mass ratio of methanol to water of 9:1, 8: 2, 7: 3 were determined with a static equilibrium still, and wer... In this article VLE data for a ternary system (propylene-methanol-water) under 30~60 C,0. 3~0. 9 MPa with a mass ratio of methanol to water of 9:1, 8: 2, 7: 3 were determined with a static equilibrium still, and were correlated by using Peng-Robinson model. The average relative error ofpropylene concentration in liquid phase is 1. 46 %. The results indicate that the models are very suitablefor the ternary system and the data are reliable. 展开更多
关键词 propylene methanol water vapor-liquid phase equilibria Peng-Robinson model
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Morphology Control of SrCO_3 Crystals using Complexons as Modifiers in the Ethanol-water mixtures 被引量:3
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作者 张明轩 霍冀川 +2 位作者 于永生 崔彩萍 雷永林 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第10期1223-1229,共7页
Using SrC12-6H2O and Na2CO3 as the main raw materials and adding different complexons as modifiers with simple co-precipitation method, SrCO3 crystals with distinct morphologies like spherical, bundle-like, overlappin... Using SrC12-6H2O and Na2CO3 as the main raw materials and adding different complexons as modifiers with simple co-precipitation method, SrCO3 crystals with distinct morphologies like spherical, bundle-like, overlapping plate-like, hexagonal star-like, dumbbell-like, etc. can be synthesized in the ethanol-water mixtures. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectrograph (FT-IR). The interrelated effect mechanism is presented in the end. Results show that the modifier carboxyl groups play a significant role in controlling the SrCO3 crystal morphologies, which can alter the crystal growth unit (Sr^2+) supply mode and induce the crystal formation with the morphologies matching their spatial configurations. 展开更多
关键词 SrCO3 complexon MODIFIER morphology control ethanol-water mixtures
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