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Deciphering the toxic effects of polystyrene nanoparticles on erythropoiesis at single-cell resolution 被引量:1
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作者 Eun Jung Kwon Hyeon Mi Sung +10 位作者 Hansong Lee Soyul Ahn Yejin Kim Chae Rin Lee Kihun Kim Kyungjae Myung Won Kyu Kim Dokyoung Kim Sanghwa Jeong Chang-Kyu Oh Yun Hak Kim 《Zoological Research》 2025年第1期165-176,共12页
Polystyrene nanoparticles pose significant toxicological risks to aquatic ecosystems,yet their impact on zebrafish(Danio rerio)embryonic development,particularly erythropoiesis,remains underexplored.This study used si... Polystyrene nanoparticles pose significant toxicological risks to aquatic ecosystems,yet their impact on zebrafish(Danio rerio)embryonic development,particularly erythropoiesis,remains underexplored.This study used single-cell RNA sequencing to comprehensively evaluate the effects of polystyrene nanoparticle exposure on erythropoiesis in zebrafish embryos.In vivo validation experiments corroborated the transcriptomic findings,revealing that polystyrene nanoparticle exposure disrupted erythrocyte differentiation,as evidenced by the decrease in mature erythrocytes and concomitant increase in immature erythrocytes.Additionally,impaired heme synthesis further contributed to the diminished erythrocyte population.These findings underscore the toxic effects of polystyrene nanoparticles on hematopoietic processes,highlighting their potential to compromise organismal health in aquatic environments. 展开更多
关键词 polystyrene nanoparticles Zebrafish embryos Single-cell RNA sequencing ERYTHROPOIESIS
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The Influence of Visible Light on the Consumption Rate of Expanded Polystyrene by Zophobas morio Larvae
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作者 Tyler J. Ferenz 《Advances in Entomology》 2025年第1期107-119,共13页
The process of disposing of expanded polystyrene (EPS) is by burning it in municipal incinerators. This process gives off EPS microplastics, which can find their way into water, food, blood, and major organ systems. Z... The process of disposing of expanded polystyrene (EPS) is by burning it in municipal incinerators. This process gives off EPS microplastics, which can find their way into water, food, blood, and major organ systems. Zophobas morio larvae are capable of consuming and breaking down EPS within their digestive tracts by minimizing the spread of microplastics. Studies of the consumption of EPS by Z. morio larvae are typically conducted under white or no visible light treatments. This study tested whether the color of visible light influenced the consumption rate of EPS by Z. morio larvae. If Z. morio larvae consume EPS under visible light, then visible light will influence the amount of EPS consumed. If results suggest that the consumption rate is influenced by visible light colors, then Z. morio larvae could be a solution for recycling EPS. This study’s procedure placed Z. morio larvae into 25 jars under one of six visible light treatments of red, yellow, green, blue, white, and no visible light. Each jar contained a pre-weighed block of EPS and six Z. morio larvae. After two weeks, the Z. morio larvae were removed from the jars, and the difference between each pre-weighed EPS block and the weight of the same partially consumed block was recorded in three trials. The data indicates that green and blue visible light treatments resulted in the greatest amount of EPS consumed by Z. morio larvae while the red and yellow had the least amount of EPS consumed by the Z. morio larvae. In conclusion, results indicate that green and blue visible light, compared to the no visible light treatment, could be used to influence the Z. morio larvae to consume more EPS. Green and blue visible light and Z. morio larvae could make the recycling process of EPS more environmentally friendly when used in households or by local environmental organizations. 展开更多
关键词 Zophobas morio Z. morio Superworm LARVAE Visible Light Expanded polystyrene EPS STYROFOAM Consumption Rate POLLUTION RECYCLING Nanoplastics Microplastics
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Bio-based polyurethane for road engineering applications:A comprehensive review
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作者 Qingxu Li Zengping Zhang +3 位作者 Zhongbao Shi Yekun Zhang Xiaoyi Ban Hao Liu 《Journal of Road Engineering》 2025年第4期513-530,共18页
With the escalating global emphasis on environmental conservation and sustainable development,enhancing the service quality and durability of road surfaces and facilitating the green development of highways have comma... With the escalating global emphasis on environmental conservation and sustainable development,enhancing the service quality and durability of road surfaces and facilitating the green development of highways have commanded considerable attention.Bio-based polyurethane,on account of its remarkable physical and chemical properties,green,sustainable and renewable capacity,as well as its structural design capabilities,has drawn widespread attention and numerous studies have been carried out.It has gradually started to substitute traditional petroleum-based polyurethane materials in road engineering.Nevertheless,the application of bio-based polyurethane materials in road engineering remains in the exploratory phase.To stimulate the application research of bio-based polyurethane materials in road engineering and offer additional research directions,this paper reviews the research advancements of bio-based polyurethane materials and their applications in road engineering.The fundamental classification of bio-based polyurethane is introduced.The characteristics and challenges associated with various preparation methods for bio-based polyurethane are described.The influence of bio-based polyurethane on road engineering materials are analyzed.The evaluation indicators of bio-based polyurethane within the life cycle of road engineering are investigated.Finally,the development tendency towards in road engineering applications are forecasted.This paper provides a reference for the study of bio-based polyurethane materials in road engineering applications. 展开更多
关键词 bio-based materials POLYURETHANE Life cycle assessment Environmentally friendly
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Modification mechanism of caking property of polystyrene waste using low-temperature pyrolysis and its use in coal-blending coking
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作者 Xiangchun Liu Ying Chen +1 位作者 Huan Song Ping Cui 《Chinese Journal of Chemical Engineering》 2025年第1期93-101,共9页
Polystyrene(PS)waste was depolymerized using a low-temperature pyrolysis treatment(LTPT)to increase its caking index.The mechanism of caking index modification was revealed by using Fourier transform infrared spectros... Polystyrene(PS)waste was depolymerized using a low-temperature pyrolysis treatment(LTPT)to increase its caking index.The mechanism of caking index modification was revealed by using Fourier transform infrared spectroscopy,thermogravimetric(TG)analysis,pyrolysis-gas chromatography with mass spectrometric detection,and solid-state^(13)C nuclear magnetic resonance spectroscopy.The crucible coal-blending coking tests were carried out using an industrial coal mixture and the treated-PS with the highest caking index(PS300)or raw PS.Some properties of the resultant cokes were also analyzed.It was demonstrated that the caking index of PS dramatically increased by LTPT;however,exceeding 300℃ did not yield any benefit.The caking index increased due to the formation of the caking components,whose molecules are medium in size,caused by LTPT.Additionally,the coke reactivity index of the coke obtained from the mixture containing PS300 decreased by 5.1%relative to that of the coke made from the mixture with PS and the coke strength after reaction index of the former increased by 7.3% compared with that of the latter,suggesting that the ratio of depolymerized PS used for coal-blending coking could increase relative to that of PS. 展开更多
关键词 polystyrene PYROLYSIS Caking index Coking property
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Bio-based Epoxy Composites Demonstrating High Temperature Breakdown Strength and Thermal Conductivity for High Voltage Insulation
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作者 Ke-Rong Yang Jin-Yue Dai +2 位作者 Shuai-Peng Wang Wei-Wei Zhao Xiao-Qing Liu 《Chinese Journal of Polymer Science》 2025年第1期40-52,I0006,共14页
The demand for energy-efficient and environmental-friendly power grid construction has made the exploitation of bio-based electrical epoxy resins with excellent properties increasingly important.This work developed th... The demand for energy-efficient and environmental-friendly power grid construction has made the exploitation of bio-based electrical epoxy resins with excellent properties increasingly important.This work developed the bio-based electrotechnical epoxy resins based on magnolol.High-performance epoxy resin(DGEMT)with a double crosslinked points and its composites(Al_(2)O_(3)/DGEMT)were obtained taking advantages of the two bifunctional groups(allyl and phenolic hydroxyl groups)of magnolol.Benefitting from the distinctive structure of DGEMT,the Al_(2)O_(3)/DGEMT composites exhibited the advantages of intrinsically high thermal conductivity,high insulation,and low dielectric loss.The AC breakdown strength and thermal conductivity of Al_(2)O_(3)/DGEMT composites were 35.5 kV/mm and 1.19 W·m-1·K-1,respectively,which were 15.6%and 52.6%higher than those of petroleum-based composites(Al_(2)O_(3)/DGEBA).And its dielectric loss tanδ=0.0046 was 20.7%lower than that of Al_(2)O_(3)/DGEBA.Furthermore,the mechanical,thermal and processing properties of Al_(2)O_(3)/DGEMT are fully comparable to those of Al_(2)O_(3)/DGEBA.This work confirms the feasibility of manufacturing environmentally friendly power equipment using bio-based epoxy resins,which has excellent engineering applications. 展开更多
关键词 bio-based epoxy composites MAGNOLOL Breakdown strength Thermal conductivity Dielectric loss
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Synthesis of amine-functionalized polystyrene resin-based globular adsorbents for efficient and selective removal of As and Sb species
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作者 Xiao Yang Wenjing Liu +9 位作者 Jiarui Kong Xiangcheng Shan Qiupei Lei Zhipeng Yin Runzeng Liu Min Zhang Qingzhe Zhang Yongguang Yin Chuanyong Jing Yong Cai 《Chinese Chemical Letters》 2025年第11期222-230,共9页
The removal of highly toxic arsenic(As)and antimony(Sb)contaminants in water by adsorption presents a great challenge worldwide.Conventional adsorbents exhibit insufficient efficacy for removing pentavalent oxyanions,... The removal of highly toxic arsenic(As)and antimony(Sb)contaminants in water by adsorption presents a great challenge worldwide.Conventional adsorbents exhibit insufficient efficacy for removing pentavalent oxyanions,As(Ⅴ)and Sb(Ⅴ),which are predominant compared with the trivalent species,As(Ⅲ)and Sb(Ⅲ),in surface waters.Here,we synthesized a novel composite adsorbent,amine-functionalized polystyrene resin loaded with nano TiO_(2)(Am PSd-Ti).The mm-scale spheres showed outstanding adsorption capacities for As(Ⅲ),As(Ⅴ),Sb(Ⅲ),and Sb(Ⅴ)at 73.85,153.29,86.80,and 123.71 mg/g,respectively.Am PSd-Ti exhibited selective adsorption for As and Sb in the presence of Cl^(-),NO_(3)^(-),SO_(4)^(2-),and F^(-).As and Sb were adsorbed by the nano-sized TiO_(2)confined in the porous resin via forming innersphere complexes.The protonated amine groups enhanced the adsorption of As(Ⅴ)and Sb(Ⅴ)by electrostatic attraction and hydrogen bonding,which was confirmed by experimental results and molecular dynamics simulations.Fixed-bed column tests showed breakthrough curves with adsorption capacities of1.38 mg/g(6600 BV)and 6.65 mg/g(1260 BV)upon treating real As-contaminated groundwater and Sbcontaminated industrial wastewater.Our study highlights a feasible strategy by incorporating inorganic metal oxides into organic polymers to achieve highly efficient removal of As and Sb in real-world scenarios. 展开更多
关键词 polystyrene resins Titanium dioxide ARSENIC ANTIMONY Adsorption mechanism
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Optical transmittance and pulse shape discrimination of polystyrene/poly(methyl methacrylate)-based plastic scintillators
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作者 Yi-Yao Liang Ying-Du Liu +2 位作者 Pu-Sen Wang Jie Bao Xiao-Ping Ouyang 《Nuclear Science and Techniques》 2025年第1期94-102,共9页
Polymethyl methacrylate(PMMA)is an optically transparent thermoplastic with favorable processing conditions.In this study,a series of plastic scintillators are prepared via thermal polymerization,and the impact of PMM... Polymethyl methacrylate(PMMA)is an optically transparent thermoplastic with favorable processing conditions.In this study,a series of plastic scintillators are prepared via thermal polymerization,and the impact of PMMA content on their transparency and pulse shape discrimination(PSD)ability is investigated.The fabricated samples,comprising a polystyrene(PS)-PMMA matrix,30.0 wt%2,5-diphenyloxazole(PPO),and 0.2 wt%9,10-diphenylanthracene(DPA),exhibit high transparency with transmissivity ranging from 70.0 to 90.0%(above 415.0 nm)and demonstrate excellent n/γdiscrimination capability.Transparency increased with increasing PMMA content across the entire visible light spectrum.However,the PSD performance gradually deteriorated when the aromatic matrix was replaced with PMMA.The scintillator containing 20.0 wt%PMMA demonstrated the best stability concerning PSD properties and relative light yields. 展开更多
关键词 Neutron detection Plastic scintillation Pulse shape discrimination Polymethyl-methacrylate polystyrene
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Development of Oilfield Blockage Relief and Injection System Based on Bio-Based Surfactants
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作者 Wang Fei Chen Zhaoxian +2 位作者 Liu Gang Zhang Huili Hu Meijuan 《China Detergent & Cosmetics》 2025年第3期40-46,共7页
By investigating the performance characteristics of the bio-based surfactant 8901A,a composite decontamination and injection system was developed using 8901A as the primary agent,tailored for application in low-permea... By investigating the performance characteristics of the bio-based surfactant 8901A,a composite decontamination and injection system was developed using 8901A as the primary agent,tailored for application in low-permeability and heavy oil reservoirs under varying temperature conditions.The results demonstrate that this system effectively reduces oil–water interfacial tension,achieving an ultra-low interfacial tension state.The static oil washing efficiency of oil sands exceeds 85%,the average pressure reduction rate reaches 21.55%,and the oil recovery rate improves by 13.54%.These enhancements significantly increase the system’s ability to dissolve oilbased blockages,thereby lowering water injection pressure caused by organic fouling,increasing the injection volume of injection wells,and ultimately improving oil recovery efficiency. 展开更多
关键词 bio-based surfactants oil extraction technology pressure reduction and blockage relief
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Enhanced removal of polystyrene nanoplastics by air flotation modified by dodecyltrimethylammonium chloride:Performance and mechanism
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作者 Jinhui Xu Yanting Zhang +6 位作者 Kecheng Wen Xinyu Wang Zhiwei Yang Yuan Huang Guozhong Zheng Lupeng Huang Jing Zhang 《Chinese Chemical Letters》 2025年第5期588-594,共7页
Nanoplastics exhibit greater environmental biotoxicity than microplastics and can be ingested by humans through major routes such as tap water,bottled water and other drinking water.Nanoplastics present a challenge fo... Nanoplastics exhibit greater environmental biotoxicity than microplastics and can be ingested by humans through major routes such as tap water,bottled water and other drinking water.Nanoplastics present a challenge for air flotation due to their minute particle size,negative surface potential,and similar density to water.This study employed dodecyltrimethylammonium chloride(DTAC)as a modifier to improve conventional air flotation,which significantly enhanced the removal of polystyrene nanoplastics(PSNPs).Conventional air flotation removed only 3.09%of PSNPs,while air flotation modified by dodecyltrimethylammonium chloride(DTAC-modified air flotation)increased the removal of PSNPs to 98.05%.The analysis of the DTAC-modified air flotation mechanism was conducted using a combination of instruments,including a zeta potential analyzer,contact angle meter,laser particle size meter,high definition camera,scanning electron microscope(SEM),energy dispersive spectrometer(EDS)and Fourier transform infrared spectrometer(FTIR).The results indicated that the incorporation of DTAC reversed the electrostatic repulsion between bubbles and PSNPs to electrostatic attraction,significantly enhancing the hydrophobic force in the system.This,in turn,improved the collision adhesion effect between bubbles and PSNPs.The experimental results indicated that even when the flotation time was reduced to 7min,the DTACmodified air flotation still achieved a high removal rate of 96.26%.Furthermore,changes in aeration,pH,and ionic strength did not significantly affect the performance of the modified air flotation for the removal of PSNPs.The removal rate of PSNPs in all three water bodies exceeded 95%.The DTAC-modified air flotation has excellent resistance to interference from complex conditions and shows great potential for practical application. 展开更多
关键词 polystyrene nanoplastics Dodecyltrimethylammonium chloride Modified air flotation MECHANISM Effectiveness and stability
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Comprehensive review of aging phenomena in conventional and bio-based asphalt binders:Challenges and future directions
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作者 Farhad Sakanlou Chiara Riccardi Massimo Losa 《Journal of Road Engineering》 2025年第4期481-512,共32页
Aging plays a critical role in determining the durability and long-term performance of asphalt pavements,as it is influenced by both external factors(e.g.,temperature,ultraviolet(UV)radiation,moisture,oxidative gases)... Aging plays a critical role in determining the durability and long-term performance of asphalt pavements,as it is influenced by both external factors(e.g.,temperature,ultraviolet(UV)radiation,moisture,oxidative gases)and internal factors such as binder composition.Although laboratory simulations of aging are well established for conventional bituminous binders,limited attention has been paid to replicating and evaluating aging processes in bio-based binders.This review provides a comprehensive analysis of current laboratory techniques for simulating and assessing binder aging,with a focus on two key areas:aging simulation protocols and evaluation methodologies.The analysis shows that although several efforts have been made to incorporate external aging factors into lab simulations,significant challenges persist,especially in the case of bio-based binders,which are characterized by a high variability in composition and limited understanding of their aging behavior.Current evaluation approaches also exhibit limitations.Improvements are needed in the molecular-level analysis of oxidation(e.g.,through more representative oxidation modelsin molecular dynamicssimulations),in the separation and quantification of binder constituents,and in the application of advanced techniques such as fluorescence microscopy to better characterize polymer dispersion.To enhance the reliability of laboratory simulations,future research should aim to improve the correlation between laboratory and field aging,define robust aging indexes,and refine characterization methods.These advancements are particularly critical for bio-based binders,whose performance is highly sensitive to aging and for which standard test protocols are still underdeveloped.A deeper understanding of aging mechanisms in both polymer-modified and biobased binders,along with improved analytical tools for assessing oxidative degradation and morphological changes,will be essential to support the development of sustainable,high-performance paving materials. 展开更多
关键词 Binder aging bio-based binder aging UV aging Moisture aging Molecular dynamics simulation Aging index
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Influence of Millet Husks on the Physical, Mechanical and Thermal Performance of a Lightweight Bio-Based Concrete
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作者 Soubérou Gbèdossou Saloufou Valéry KouandétéDoko +2 位作者 Edem Chabi Emmanuel Olodo Mohamed Gibigaye 《材料科学与工程(中英文A版)》 2025年第1期19-31,共13页
In the context of transitioning toward more sustainable construction materials,this study explores the impact of incorporating millet husks as an alternative to sand on the physical,mechanical,and thermal performance ... In the context of transitioning toward more sustainable construction materials,this study explores the impact of incorporating millet husks as an alternative to sand on the physical,mechanical,and thermal performance of lightweight concrete.Through a mixture design approach,five formulations were selected and thoroughly characterized.The analysis of iso-response curves enabled an in-depth assessment of the cross-effects between formulation parameters and their interactions on the final properties of the material.The results show that integrating millet husks leads to a significant reduction in density,reaching up to 21%,while maintaining notable mechanical performance.A balanced formulation of sand and fibers achieved a maximum compressive strength of 12.11 MPa,demonstrating that,under specific conditions,plant fibers actively contribute to the structural integrity of the composite.In tensile strength,the positive influence of fibers is even more pronounced,with a maximum resistance of 8.62 MPa,highlighting their role in enhancing material cohesion.From a thermal perspective,millet husks reduce both thermal conductivity and effusivity,thereby limiting heat transfer and accumulation within the composite.Iso-response curve analysis reveals that these effects are directly linked to the proportions of the constituents and that achieving an optimal balance between sand,fibers,and cement is key to maximizing performance.These findings demonstrate that the adopted approach allows moving beyond conventional substitution methods by identifying optimal configurations for the design of lightweight bio-based concretes that are both strong and insulating,thereby confirming the potential of millet husks in developing lightweight concretes suitable for sustainable construction applications. 展开更多
关键词 Lightweight bio-based materials plant fibers mixture design iso-response analysis formulation optimization mineral aggregate substitution.
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One-step Preparation of Brush-type Polystyrene(PS)-SiO_(2)-Poly(2-hydroxyethyl methacrylate)Janus Nanoparticle to Compatibilize PS/Poly(methyl methacrylate)Blends
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作者 Feng-Yuan Tu Ming-Feng Wang +5 位作者 Gang Zhong Hua-Wei Qiao Bo-Tuo Zheng Can-Pei Liu Ming-Feng Chen Hua-Gui Zhang 《Chinese Journal of Polymer Science》 2025年第8期1375-1386,共12页
Compatibilization is crucial for the blending of immiscible polymers to develop high-performance composites;however,traditional compatibilization by copolymers(pre-made or in-situ generation)suffers from weak interfac... Compatibilization is crucial for the blending of immiscible polymers to develop high-performance composites;however,traditional compatibilization by copolymers(pre-made or in-situ generation)suffers from weak interface anchoring,and inorganic particles have gained extensive attention recently owing to their large interfacial desorption energy,while their low affinity to bulk components is a drawback.In this study,an interfacial atom transfer radical polymerization(ATRP)technique was employed to grow polystyrene(PS)and poly(2-hydroxyethyl methacrylate)(PHEMA)simultaneously on different hemispheres of Br-functionalized SiO_(2) nanoparticles to stabilize a Pickering emulsion,whereby a brush-type Janus nanoparticle(SiO_(2)@JNP)was developed.The polymer brushes were well-characterized,and the Janus feature was validated by transmission electron microscope(TEM)observation of the sole hemisphere grafting of SiO_(2)-PS as a control sample.SiO_(2)@JNP was demonstrated to be an efficient compatibilizer for a PS/poly(methyl methacrylate)(PMMA)immiscible blend,and the droplet-matrix morphology was significantly refined.The mechanical strength and toughness of the blend were synchronously enhanced at a low content SiO_(2)@JNP optimized~0.9 wt%,with the tensile strength,elongation at break and impact strength increased by 17.7%,26.6%and 19.6%,respectively.This enhancement may be attributed to the entanglements between the grafted polymer brushes and individual components that improve the particle-bulk phase affinity and enforce interfacial adhesion. 展开更多
关键词 COMPATIBILIZATION Janus particles polystyrene Poly(2-hydroxyethyl methacrylate) SiO_(2) Interface
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Polystyrene microplastics affect the early life stages of large yellow croaker Pseudosciaena crocea
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作者 Hailing YANG Fangzhu WU +6 位作者 Fangping CHEN Jiangning ZENG Qikun YANG Lukuo MA Tianqi ZHAI Yu ZHOU Wei HUANG 《Journal of Oceanology and Limnology》 2025年第2期644-655,共12页
Microplastics(MPs)have garnered significant international scrutiny as an emerging environmental pollutant,constituting one of the four principal global environmental threats and posing potential health hazards to huma... Microplastics(MPs)have garnered significant international scrutiny as an emerging environmental pollutant,constituting one of the four principal global environmental threats and posing potential health hazards to humans.However,data on the impact of MPs on the early life of the commercially important fish remain limited.In this study,polystyrene microspheres(PS-MPs)(1 and 5μm)were used to investigate the effects of MPs on the growth,development,and metabolism in early life stages of large yellow croaker Pseudosciaena crocea.Results indicate that MPs were enriched in the gastrointestinal tract and gills of the fish.In addition,PS-MPs(1μm)exhibited no obvious effects on embryo hatching and heart rates,while increased the mortality rate(23.00%vs.control 14.99%)and decreased the body length(4098.61±447.03μm vs.control with 2827.04±254.75μm)of the larvae at the highest exposure concentration(5×10^(4)items/L).Metabolomics analysis revealed that PS-MPs(5μm)induced mild perturbations in phospholipid metabolism,specifically alterations in phosphatidylethanolamine(PE)levels.These changes influenced the cell membranes of juvenile fish,and consequently elicited inflammatory responses,disrupted lipid homeostasis,and affected other critical physiological processes.Ultimately,these effects may avoid the growth retardation and potential mortality.Therefore,PS-MPs could affect negatively the fish health in the early life stage,which has implications for aquatic ecosystems. 展开更多
关键词 polystyrene microplastic(PS-MP) early life stage Pseudosciaena crocea large yellow croaker DEVELOPMENT METABOLOMIC
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Switching electronic effects of UiO-67-Pd using fluorinated ligands for catalytic oxidative arylation of bio-based furfuryl alcohol
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作者 Dongwen Guo Guohui Zeng +1 位作者 Jinxing Long Biaolin Yin 《Chinese Journal of Catalysis》 2025年第2期230-240,共11页
An efficient and novel approach is proposed for oxidative arylation of bio-based furfuryl alcohol(FA)to aryl furans(AFs),a versatile monomer of photoelectric materials,in the presence of UiO-67-Pd(F)with phenanthrolin... An efficient and novel approach is proposed for oxidative arylation of bio-based furfuryl alcohol(FA)to aryl furans(AFs),a versatile monomer of photoelectric materials,in the presence of UiO-67-Pd(F)with phenanthroline/bipyridine,and poly-F substituted phenyl ligands as the mixture linkers.The results of control experiments and theoretical calculations reveal that the–F on the phenyl linkers efficiently tunes the electron-deficient nature of Pd through the Zr_(6) clusters bridges,which favors the adsorption and activation of the furan ring.Furthermore,the conjugation of different nitrogen-containing ligands facilitates Pd coordination for the Heck-type insertion and subsequent electrophilic palladation,respectively.As a result,the oxidative arylation of FA derivatives is substantially enhanced because of these electronic and steric synergistic effects.Under the optimized conditions,72.2%FA conversion and 74.8%mono aryl furan(MAF)selectivity are shown in the Heck-type insertion.Meanwhile,85.3%of MAF is converted,affording 74.8%selectivity of final product(AFs)in the subsequent electrophilic palladation reaction.This process efficiency is remarkably higher than that with homogeneous catalysts.In addition,furan-benzene polymer obtained from the halogen-free synthesis catalyzed by UiO-67-Pd(F)show significantly better properties than that from conventional Suzuki coupling method.Therefore,the present work provides a new insight for useful AFs synthesis by oxidative arylation of bio-furan via rational tunning the metal center micro-environment of heterogeneous catalyst. 展开更多
关键词 bio-based furan Catalytic oxidative arylation UiO-67-Pd(F)catalyst Ligand regulation Charge separation
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Effect of Temperature and Sulfonation Extent on Fluorescence Emission of Sulfonated Polystyrene
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作者 陈旭东 沈家瑞 《中山大学学报论丛》 1997年第5期59-62,共4页
研究不同磺化度的磺化聚苯乙烯(SPS)的荧光特性,SPS的荧光光谱在285,335和380nm的发射峰分别对应于单体、激基缔合物及类激基缔合物的荧光发射.基态磺化苯乙烯基团形成的二聚体在光激发下产生类激基缔合物,类激... 研究不同磺化度的磺化聚苯乙烯(SPS)的荧光特性,SPS的荧光光谱在285,335和380nm的发射峰分别对应于单体、激基缔合物及类激基缔合物的荧光发射.基态磺化苯乙烯基团形成的二聚体在光激发下产生类激基缔合物,类激基缔合物荧光随着SPS磺化度的增加而增强.稀溶液中SPS激基缔合物形的活化能和焓随着SPS磺化度的增加而增大。 展开更多
关键词 磺化聚苯乙烯 磺化度 荧光 活化能 激基缔合物
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Fabrication of macroporous polystyrene/graphene oxide composite monolith and its adsorption property for tetracycline 被引量:9
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作者 Le-Chen Chen Shan Lei +2 位作者 Mo-Zhen Wang Jun Yang Xue-Wu Ge 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第4期511-517,共7页
Macroporous polystyrene microsphere/graphene oxide(PS/GO) composite monolith was first prepared using Pickering emulsion droplets as the soft template. The Pickering emulsion was stabilized by PS/GO composite partic... Macroporous polystyrene microsphere/graphene oxide(PS/GO) composite monolith was first prepared using Pickering emulsion droplets as the soft template. The Pickering emulsion was stabilized by PS/GO composite particles in-situ formed in an acidic water phase. With the evaporation of water and the oil phase(octane), the Pickering emulsion droplets agglomerated and combined with each other, forming a three-dimensional macroporous PS/GO composite matrix with excellent mechanical strength. The size of the macrospores ranged from 4 mm to 20 mm. The macroporous PS/GO composite monolith exhibited high adsorption capacity for tetracycline(TC) in an aqueous solution at p H 4–6. The maximum adsorption capacity reached 197.9 mg g 1at p H 6. The adsorption behaviour of TC fitted well with the Langmuir model and pseudo-second-order kinetic model. This work offers a simple and efficient approach to fabricate macroporous GO-based monolith with high strength and adsorption ability for organic pollutants. 展开更多
关键词 Graphene oxide polystyrene microsphere Macroporousm ADSORPTION TETRACYCLINE
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Preparation of luminescent polystyrene microspheres via surface-modified route with rare earth(Eu^(3+) and Tb^(3+))complexes linked to 2,2'-bipyridine 被引量:8
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作者 Zhen-Xiong Ma Qi-Tao Zhang +3 位作者 Jun-Liang Liu Chang-Hao Yan Ming Zhang Teruhisa Ohno 《Rare Metals》 SCIE EI CAS CSCD 2015年第8期590-594,共5页
Luminescent polystyrene microspheres were easily fabricated from poly(styrene-co-methacrylic acid)and aqueous RE(III) chloride solution(RE=Eu, Tb) in the presence of 2,20-bipyridine as second ligand. The negative char... Luminescent polystyrene microspheres were easily fabricated from poly(styrene-co-methacrylic acid)and aqueous RE(III) chloride solution(RE=Eu, Tb) in the presence of 2,20-bipyridine as second ligand. The negative charges of carboxyl groups on the surface of microspheres coordinated with rare earth ions at first, such as complexes covalently linked to 2,20-bipyridine, resulting in strong photoluminescence. Various methods, including transmission electron microscope(TEM), scanning electron microscope(SEM), energy dispersive spectroscopy(EDS),Fourier transform infrared spectroscopy(FT-IR), and fluorescence spectrophotometer, were used to characterize the resultant polystyrene composite microspheres. This work highlights the idea that it is facile to synthesis luminescent microspheres by surface-modified method directly. 展开更多
关键词 LUMINESCENT polystyrene TERBIUM EUROPIUM 2 2’-bipy
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HALOMETHYLATION OF POLYSTYRENE AND SUBSEQUENT PYRIDINATION VIA A HOMOLYTIC PATHWAY 被引量:3
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作者 Sad Moulay Nadia Mehdi 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第6期627-635,共9页
Chloromethylation of polystyrene (PS) with two different chloromethylating systems methylal/thionyl chloride and paraformaldehyde/trimethylchlorosilane was studied. Soluble chloromethylated polystyrene with a degree... Chloromethylation of polystyrene (PS) with two different chloromethylating systems methylal/thionyl chloride and paraformaldehyde/trimethylchlorosilane was studied. Soluble chloromethylated polystyrene with a degree of substitution of 89% was obtained. The Conant-Finkelstein reaction on the chloromethylated PS afforded soluble iodomethylated polystyrene with a degree of substitution as high as 96%. The reaction conditions of Minisci were employed to radically pyridinate PS via its iodomethylated derivative. Polyelectrolytes were formed which could be converted to normal polymers by treatment with a 20% aqueous solution of NaOH. 展开更多
关键词 Chloromethylated polystyrene Conditions of Minisci Iodomethylated polystyrene Pyridinated polystyrene.
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POLYMER-CLAY NANOCOMPOSITES:CHEMICAL GRAFTING OF POLYSTYRENE ONTO CLOISITE 20A 被引量:4
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作者 Yagoub Mansoori Khadijeh Roojaei +1 位作者 Mohammad RezaZamanloo Gholamhassan Imanzadeh 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2012年第6期815-823,共9页
An account of the experiments on preparing polystyrene (PS) nanocomposites through grafting the polymer onto organophilic montmorillonite is reported. Cloisite 20A was reacted with vinyltrichlorosilane to replace th... An account of the experiments on preparing polystyrene (PS) nanocomposites through grafting the polymer onto organophilic montmorillonite is reported. Cloisite 20A was reacted with vinyltrichlorosilane to replace the edge hydroxyl groups of the clay with a vinyl moiety. Because the reaction may liberate HC1, it was performed in the presence of sodium hydrogencarbonate to prevent the exchange of quaternary alkylammonium cations withH+ ions. Only the silanol groups on the edge of the clay react with vinyltrichlorosilane. The radical polymerization of the product with styrene as a vinyl monomer leads to chemical grafting of PS onto the montmorillonite surface. The homopolymer formed during polymerization was separated from the grafted organoclay by Soxhlet extraction. Chemical grafting of the polymer onto Cloisite 20A was confirmed by infrared spectroscopy. The prepared nanocomposite materials and the grafted nano-particles were studied by XRD. Exfoliated nanocomposites may be obtained for 0.5 wt%-1wt% clay content. The nanocomposites were studied by thermogravimertic analysis (TGA) dynamic thermal analysis (DTA) and dynamic mechanical analysis (DMTA). 展开更多
关键词 GRAFTING polystyrene NANOCOMPOSITES Cloisite 20A Organophilic clay.
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Experimental Study of Lightweight Expanded Polystyrene Aggregate Concrete Containing Silica Fume and Polypropylene Fibers 被引量:4
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作者 陈兵 刘睫 陈龙珠 《Journal of Shanghai Jiaotong university(Science)》 EI 2010年第2期129-137,共9页
We developed a new structural lightweight concrete by totally or partially replacing coarse and fine aggregates in high performance concrete by expanded polystyrene (EPS) beads. In this work,the sizes of EPS bead were... We developed a new structural lightweight concrete by totally or partially replacing coarse and fine aggregates in high performance concrete by expanded polystyrene (EPS) beads. In this work,the sizes of EPS bead were 1.0,2.5 and 6.3 mm. Lightweight EPS concretes with a wide range of concrete densities and compressive strengths were successfully developed. Compressive strength,splitting tensile strength,shrinkage,and water absorption were examined. Additionally,fine silica fume (SF) and polypropylene (PP) fibers were added to improve the mechanical and shrinkage properties of EPS concretes. The results show that fine SF greatly increases the bond strength between the EPS beads and cement paste,thus increasing the compressive strength of EPS concrete. With inclusion of PP fibers,drying shrinkage properties are significantly improved. 展开更多
关键词 expanded polystyrene CONCRETE WORKABILITY compressive strength adsorption SHRINKAGE
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