Carbon-fiber-reinforced plastics(CFRP)with improved mechanical properties based on modified epoxy binders were investigated in this study.By adding 15 parts by weight(p.b.w.)of copolymer of polysulfone with cardo phth...Carbon-fiber-reinforced plastics(CFRP)with improved mechanical properties based on modified epoxy binders were investigated in this study.By adding 15 parts by weight(p.b.w.)of copolymer of polysulfone with cardo phthalide group(PSFP-70C)to the epoxyanhydride binder,the flexural strength of the epoxy polymer was increased by 60%,the CFRP based on it by 57%,the flexural modulus of the epoxy polymer was increased by 83%,and the composite by 96%.The adhesion strength of the binder to carbon fiber reached a high level at 10 p.b.w.of thermoplastic modifier and increased by 65%compared to the unmodified binder.Scanning electron microscopy(SEM)was used to determine that in epoxyanhydride systems with a polysulfone content of 5–15 p.b.w.,the structure belongs to the"matrix dispersion"type and with a content of 20 p.b.w.to the"interpenetrating phase"type.A heterogeneous structure was also observed using dynamic mechanical analysis.展开更多
Composite resin restorations are routinely exposed to acidic and chromogenic beverages that may alter their surface integrity over time.This in-vitro study evaluated the surface roughness behavior of two universal sin...Composite resin restorations are routinely exposed to acidic and chromogenic beverages that may alter their surface integrity over time.This in-vitro study evaluated the surface roughness behavior of two universal single-shade(Unishade)composites and two conventionalmulti-shade composites following immersion in commonly consumed staining solutions and assessed whether repolishing could restore smoothness after degradation.A total of 120 standardized disc specimens were fabricated and allocated to fourmaterial groups,with each group subdivided into distilled water,cola,and coffee immersion subgroups.Surface roughness was recorded at baseline,after one week,after one month,and following a final repolishing step using a standardized multi-step system.The findings demonstrated that Unishade composites exhibited more stable surface characteristics across all immersion periods,with changes consistently remaining below the threshold associated with biofilm accumulation.Conventional composites showed greater variability,particularly in cola,where roughness values increased significantly compared with distilled water and coffee.Repolishing substantially reduced immersion-induced roughness in all materials,although its effectiveness varied depending on composite formulation and beverage acidity.Cola produced the greatest surface alterations across all groups,highlighting the erosive potential of low-pH beverages.These results indicate that Unishade composites possess superior resistance to surface degradation,likely due to their nano-structured filler configuration and less hydrophilic resin matrices,while conventional materials appear more susceptible to acidic challenge.Within the limitations of this study,selecting surface-stable material types and applying appropriate finishing and repolishing protocols may enhance the long-term performance and esthetics of composite restorations.展开更多
Phenolic resins are widely used in thermal protection,yet achieving simultaneous improvement in thermal stability and mechanical strength remains challenging.In this work,a vinyl-modified silicone resin(VMTQ)was synth...Phenolic resins are widely used in thermal protection,yet achieving simultaneous improvement in thermal stability and mechanical strength remains challenging.In this work,a vinyl-modified silicone resin(VMTQ)was synthesized and incorporated into a boron phenolic resin(BPF)matrix.Three composite ceramic fillers,Al_(2)O_(3)-SiO_(2)-ZrO_(2)(ASZ),Al_(2)O_(3)-SiO_(2)-TiO_(2)(AST),and Al_(2)O_(3)-SiO_(2)-MgO(ASM),were further introduced to construct a multi-oxide synergistic reinforcement system.Thermogravimetric analysis shows that the maximum decomposition rate decreases by 0.2-0.3%⋅min^(-1),while the ASM/V3/BPF-3 composite exhibits a 74.53%increase in char yield at 800℃and a 163.3℃increase in initial decomposition temperature,confirming its significantly enhanced thermal stability.SEM/EDS and XRDanalyses reveal thatASZ,AST,and ASM promote the formation of stable ceramic phases,withASM generating the densest MgO-Al_(2)O_(3)-SiO_(2)composite oxide layer.Mechanical testing demonstrates that ASZ improves vertical impact strength by 23.9%,AST increases parallel impact strength by 14.1%,andASMenhances bending strength by 34.5%(316.8 MPa).These results clearly indicate that the combination of VMTQ modification with multi-oxide ceramic fillers can effectively elevate both the thermal stability and mechanical performance of BPF-based composites,providing a practical pathway for designing high-performance resins for demanding thermal-environment applications.展开更多
Poly(aryl ether sulfone)with fatty-acid side chains that crosslink with epoxy resin improves the interfacial compatibility between poly(aryl ether sulfone)and epoxy resin.Hydroxyl-terminated phenolphthalein-based poly...Poly(aryl ether sulfone)with fatty-acid side chains that crosslink with epoxy resin improves the interfacial compatibility between poly(aryl ether sulfone)and epoxy resin.Hydroxyl-terminated phenolphthalein-based poly(aryl ether sulfone)(PPES-OH)was blended with fatty-acid side-chain-modified phenolphthalein-based poly(aryl ether sulfone)(PPES-TA),with the goal of further enhancing the toughening effect on epoxy resin.In this study,PPES-OH,PPES-TA,and a composite poly(aryl ether sulfone)(PESP-TA)were synthesized.Their molecular structures and thermal properties were characterized using proton nuclear magnetic resonance spectroscopy(1H-NMR spectroscopy),thermogravimetric analysis(TGA),and differential scanning calorimetry(DSC).Subsequently,PPES-OH,PPES-TA,and PESP-TA were introduced into the anhydride-cured epoxy system to evaluate their toughening effects on epoxy resin.The curing behavior of the epoxy resin blends was investigated using DSC,which also enabled the exploration of the corresponding curing mechanisms.The thermal and mechanical properties of the toughened systems were characterized.Scanning electron microscopy(SEM)was used to observe the impact fracture surfaces of the resin,which revealed‘fish-scale’structures and shear bands in the resin system after curing.These findings demonstrate that similar thermoplastic chains become entangled with one another,forming additional physical cross-links.This enhanced the interfacial compatibility between the thermoplastic and thermoset resins,which,in turn,significantly improved the impact toughness and elongation at break of the system.In summary,PESP-TA has emerged as a reactive thermoplastic toughening agent that is feasible for preparation and has significant practical application potential.展开更多
Different reactive flame retardants have been extensively developed for vinyl ester resins(VERs),but very few of them can yield a flame-retardant resin that meets defined standards(e.g.UL-94 V-0 rating).In this work,p...Different reactive flame retardants have been extensively developed for vinyl ester resins(VERs),but very few of them can yield a flame-retardant resin that meets defined standards(e.g.UL-94 V-0 rating).In this work,phosphorous-containing 1-vinylimidazole salts(called VIDHP and VIDPP)were synthesized through the facile neutralization of the acid and 1-vinylimidazole.VIDHP and VIDPP were then applied as flame-retardant crosslinking agents of VERs,by which phosphorus-containing groups could be incorporated into the resin chain via ionic bonds.VIDHP/VER and VIDPP/VER showed a high curing activity and can be well cured in moderate temperatures.With 20 wt.%additions of VIDHP and VIDPP,VIDHP20/VER,and VIDPP20/VER presented a limiting oxygen index value of 29.7%and 28.4%,respectively,with the latter achieving a UL 94 V0 rating.In the cone calorimetric test,compared to the unmodified VERs,VIDPP20/VER exhibited large reductions in the peak heat release rate,total heat release rate,and total smoke release rate while VIDHP20/VER demonstrated comparatively inferior performance in terms of the heat release.VIDHP20/VER and VIDPP20/VER showed good thermal stability and presented a little lower glass transition temperature than the control sample.VIDPP with a low phosphorus oxidation state(+1)demonstrated high flame-retardant activities in the gaseous phase,whereas VIDHP with a high phosphorus oxidation state(+5)primarily exhibited efficacy in the condensed phase.展开更多
Studies on the use of renewable materials for various applications,including polymers,have gained momentum due to global climate change and the push towards a circular economy.In this study,polymer resins were develop...Studies on the use of renewable materials for various applications,including polymers,have gained momentum due to global climate change and the push towards a circular economy.In this study,polymer resins were developed through Michael 1,4-addition.The precursors were synthesized from tall oil-based acetoacetates derived from epoxidized tall oil fatty acids or their methyl esters.Two different epoxidation methods were employed:enzymatic epoxidation of tall oil fatty acids and ion-exchange resin epoxidation of tall oil fatty acid methyl esters.Following oxirane opening and transesterification with trimethylolpropane,further esterification or transesterification was carried out to obtain the acetoacetates.These synthesized acetoacetates were then reacted with acrylates of various functionalities to obtain polymer resins with differing degrees of crosslinking.The developed polymer resins were characterized using differential scanning calorimetry,dynamic mechanical analysis,and thermogravimetric analysis.The results indicated that the glass transition temperature and storage modulus of the polymer resins were significantly influenced by both the functionality of the acrylates used and the epoxidation technique employed.Higher acrylate functionality resulted in increased stiffness,while enzymatic epoxidation enhanced the polymer’s mechanical properties,nearly doubling the storage modulus,achieving approximately 470 MPa,compared to the ion-exchange resin technique.Therefore,selecting the appropriate acrylate functionality and epoxidation method could tailor the mechanical properties of the polymer resins.展开更多
The introduction of dynamic covalent bonds into the structure of epoxy resins can improve the degradation performance of the materials.But to a certain extent,it will affect the insulating properties of the resin,and ...The introduction of dynamic covalent bonds into the structure of epoxy resins can improve the degradation performance of the materials.But to a certain extent,it will affect the insulating properties of the resin,and how to balance the insulating properties and degradation performance has become an urgent problem.In this paper,the effects of different catalysts on the thermal-force-electrical properties of sorbitolbased resins were systematically investigated based on the dynamic ester bonding to construct the resin crosslinking network,and the biobased sorbitol glycidyl ether was used as the resin matrix.The experiments show that the resin system catalyzed by triethanolamine(TEOA)exhibits excellent comprehensive performance,which combines good thermal stability and mechanical properties with excellent electrical properties(breakdown field strength of 44.21 k V/mm and dielectric loss factor of 0.29%).In addition,chemical degradation tests were conducted on the resin systems with different catalysts,and the experiments showed that the produced resins could be degraded in benzyl alcohol and exhibited good degradation performance.This study provides a theoretical basis and technical path for the development of new bio-based electrical insulating materials with both high insulation and degradation properties,which is conducive to the popularization and application of bio-based resins in the field of electrical equipment.展开更多
The poor degradability and limited recyclability of epoxy resins are key challenges hindering the efficient recycling of ex-service wind turbine blades(EWTBs).Herein,we proposed a selective degradation strategy for di...The poor degradability and limited recyclability of epoxy resins are key challenges hindering the efficient recycling of ex-service wind turbine blades(EWTBs).Herein,we proposed a selective degradation strategy for direct recycling and high-value recovery of epoxy resins by introducing degradable Schiff base groups into the molecular structure and utilizing the resulting oligomers as curing agents.To realize this strategy,a series of Schiff base compounds were synthesized using bio-based vanillin and diamines and subsequently functionalized with epichlorohydrin to yield bio-based epoxy resins.The cured epoxy resins demonstrated remarkable improvements in the mechanical properties of diglycidyl ether of bisphenol-A(DGEBA),with an increases of 44.49%in the tensile strength of 38.55%,bending strength,and impact strength of 71.20%.The introduction of dynamic Schiff base bonds enabled the selective degradation of the vanillin-2,2-bis[4-(4-aminophenoxy)phenyl]propane-based epoxy resin(VBEP)/DGEBA copolymer,producing 84.20% oligomers that can be directly recycled and reused.Replacing 30 wt% of the curing agent with the oligomer increased the tensile strength of the cured sample to 75.40 MPa,surpassing that of the cured DGEBA.Under simulated acid rain and seawater exposure,the copolymer exhibited a service life of 27 years at 40℃,significantly exceeding the currently reported service life of 20 years.This study presents a sustainable strategy for the direct recycling and high-value reuse of epoxy resin,offering a promising solution for EWTBs.展开更多
Over the past several decades,the integration of IONs into EP emerged as an effective method for enhancing its mechanical properties.Nevertheless,challenges remain,especially with u-IONs,where the interfacial strength...Over the past several decades,the integration of IONs into EP emerged as an effective method for enhancing its mechanical properties.Nevertheless,challenges remain,especially with u-IONs,where the interfacial strength with EP is suboptimal,resulting in aggregation within the EP matrix and a subsequent deterioration in the mechanical performance of u-ION/EP nanocomposites.In this comprehensive review,we explored advanced chemical modification techniques tailored for IONs incorporated into EP,providing a detailed examination of the mechanical characteristics of surface cm-ION/EP nanocomposites.This review investigates various chemical modification methods and their distinct impacts on the mechanical attributes of the resulting EP nanocomposites.Special emphasis is given to addressing the persistent challenges of inadequate interfacial strength and aggregation.Furthermore,this article examines prospective surface modification approaches for inorganic oxide nanoparticles,offering a visionary outlook on methods to improve the mechanical performance of EP in future.展开更多
It is a good practice to change the site soil properties when dealing with inappropriate soils in geotechnical engineering,referred to as soil improvement.This study investigated the effects of epoxy resin LR202 stabi...It is a good practice to change the site soil properties when dealing with inappropriate soils in geotechnical engineering,referred to as soil improvement.This study investigated the effects of epoxy resin LR202 stabilizer(5 wt%of soil as an optimum percentage)and glass fibers(0 wt%,0.4 wt%and 0.8 wt%of stabilized soil)as reinforcement on silty sand’s durability.For this purpose,the unconfined compressive strength test(12 tests),durability test(12 tests),ultrasonic pulse velocity(UPV)test(48 tests),and standard compactions test(5 tests)were performed.The results of this study showed that the addition of epoxy resin improves the durability of silty sand soil.The stabilized samples containing 5 wt%epoxy resin resisted 12 freeze-thaw cycles,and the sample behavior was enhanced by adding 0.4 wt%and 0.8 wt%fibers to the stabilized samples.Hence,the samples stabilized with epoxy resin exhibited acceptable behavior under freeze-thaw durability cycles.This indicates that epoxy resin stabilizer is appropriate in areas with possible frost and exhibits good behavior.The results of the UPV test showed that it could be used as a non-destructive test to control the durability of epoxy resin-stabilized soils.展开更多
We aimed to enhance the flame retardancy of epoxy resin(EP)by synthesizing a novel,halogen-free flame retardant through a one-pot method.The synthesis utilized 9,10-dihydro-9-oxa-10-phospha-phenanthrene-10-oxide(DOPO)...We aimed to enhance the flame retardancy of epoxy resin(EP)by synthesizing a novel,halogen-free flame retardant through a one-pot method.The synthesis utilized 9,10-dihydro-9-oxa-10-phospha-phenanthrene-10-oxide(DOPO),furfurylamine(FA),and benzene propionaldehyde(BPA)as raw materials.We conducted differential scanning calorimetry(DSC)analysis to investigate the effects of FPD on the curing process and thermal properties of EP.Our findings reveal that incorporating FPD into EP can facilitate a faster curing process and increase the carbon residue post-combustion.Specifically,the FPD/EP-7 composite demonstrates a limiting oxygen index(LOI)of 34.9%and achieves a UL-94V-0 rating with a phosphorus content of 0.91wt%.These results indicate that FPD significantly enhances the thermal stability and charring rate of EP,thereby improving its flame retardancy.Although the addition of FPD slightly reduces the mechanical properties of EP,the composite material maintains excellent performance.展开更多
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
Plastic waste recycling is a focal point in today's sustainable development efforts.Improper disposal can lead to secondary pollution,posing threats to the environment and human health.In this study,we aim to recy...Plastic waste recycling is a focal point in today's sustainable development efforts.Improper disposal can lead to secondary pollution,posing threats to the environment and human health.In this study,we aim to recycle waste epoxy resin and glass fiber-reinforced epoxy resin composites via an electroless plating and a carbonization process,to design high-value-added carbon materials for microwave absorption.By pulverizing solid waste and introducing magnetic metal nanoparticles onto its surface,a composite carbon material capable of excellent microwave absorption performance was successfully developed.Specifically,doping nickel particles into carbon materials derived from glass fiber/epoxy resin achieved a wide effective absorption bandwidth(EAB)of 5.9 GHz with a matching thickness of 1.9 mm,covering nearly the entire Ku band,and achieving a minimum reflection loss(RLmin)of−36 dB simultaneously.The superior absorption performance is attributed to multiple reflections or scattering of electromagnetic waves within the material,as well as conduction and magnetic losses,dipole and interfacial polarization effects.These results demonstrate that through rational design and optimization,waste epoxy and waste glass fiber-reinforced epoxy resin-based composite materials can be effectively recycled into high-performance microwave absorbing materials,offering a straightforward and efficient pathway for waste resource utilization.展开更多
In the production of castings,intrusive gas pore represents a kind of common defects which can lead to leakage in high gas-tightness requirement castings,such as cylinder blocks and cylinder heads for engines.It occur...In the production of castings,intrusive gas pore represents a kind of common defects which can lead to leakage in high gas-tightness requirement castings,such as cylinder blocks and cylinder heads for engines.It occurs due to the intrusion of gases generated during the resin burning of the sand core into castings during the casting process.Therefore,a gas generation and flow constitution model was established,in which the gas generation rate is a function of temperature and time,and the flow of gas is controlled by the gas release,conservation,and Darcy's law.The heat transfer and gas flow during casting process was numerically simulated.The dangerous point of cores is firstly identified by a virtual heat transfer method based on the similarity between heat transfer and gas flow in the sand core.The gas pores in castings are predicted by the gas pressure,the viscosity and state of the melt for these dangerous points.Three distinct sand core structures were designed and used for the production of iron castings,and the simulated gas pore results were validated by the obtained castings.展开更多
Bioinspired active pillar structures,known for their large surface area,mechanical compliance,and diverse deformation modes,have garnered extensive research interest.Among various active pillar structures,liquid cryst...Bioinspired active pillar structures,known for their large surface area,mechanical compliance,and diverse deformation modes,have garnered extensive research interest.Among various active pillar structures,liquid crystal elastomer(LCE)pillar arrays are capable of exhibiting significant and reversible anisotropic deformation under cyclic heating and cooling,showing great potential in tunable adhesion,soft robots,and biomedical devices.However,scaling up LCE pillar manufacturing remains challenging,limiting its practical applications.In this work,a solventfree LCE resin is developed with unique features including simple operating procedure,short fabrication time,and tunable responsive temperature,enabling rapid and large-scale production of LCE pillar arrays.The LCE resin allows for the preparation of complex 3D shapes in addition to film or specimen.The fabrication time can be as short as 4 h,without the need to evaporate solvent.Moreover,the LCE resins can be adjusted with a variable phase transition temperature range from 49.4℃ to 97.7℃ by incorporating non-liquid crystal acrylate chains.The resulting active pillar array structure can undertake sequential actuation upon heating with the tunable actuation temperature.Finally,the application of these pillar arrays in multi-level information encryption is demonstrated.The LCE pillar structure introduced here offers a new strategy for constructing advanced active LCE structures with tunable responsive behavior.展开更多
BACKGROUND Due to saliva and salivary glands are reservoir to severe acute respiratory syndrome-coronavirus 2(SARS-CoV-2),aerosols and saliva droplets are primary sources of cross-infection and are responsible for the...BACKGROUND Due to saliva and salivary glands are reservoir to severe acute respiratory syndrome-coronavirus 2(SARS-CoV-2),aerosols and saliva droplets are primary sources of cross-infection and are responsible for the high human–human transmission of SARS-CoV-2.However,there is no evidence about how SARSCoV-2 interacts with oral structures,particularly resin composites.AIM To evaluate the interaction of SARS-CoV-2 proteins with monomers present in resin composites using in silico analysis.METHODS Four SARS-CoV-2 proteins[i.e.main protease,3C-like protease,papain-like protease(PLpro),and glycoprotein spike]were selected along with salivary amylase as the positive control,and their binding affinity with bisphenol-A glycol dimethacrylate,bisphenol-A ethoxylated dimethacrylate,triethylene glycol dimethacrylate,and urethane dimethacrylate was evaluated.Molecular docking was performed using AutoDock Vina and visualised in Chimera UCSF 1.14.The best ligand–protein model was identified based on the binding energy(ΔG–kcal/moL).RESULTS Values for the binding energies ranged from-3.6 kcal/moL to-7.3 kcal/moL.The 3-monomer chain had the lowest binding energy(i.e.highest affinity)to PLpro and the glycoprotein spike.Non-polymerised monomers and polymerised chains interacted with SARS-CoV-2 proteins via hydrogen bonds and hydrophobic interactions.Those findings suggest an interaction between SARS-CoV-2 proteins and resin composites.CONCLUSION SARS-CoV-2 proteins show affinity to non-polymerised and polymerised resin composite chains.展开更多
Four types of resins,P1–P4,are used as binders for FeSiBC amorphous powder,which are then press-molded and heat-treated to fabricate magnetic powder cores(MPCs).By testing the permeability,loss,density,and radial cru...Four types of resins,P1–P4,are used as binders for FeSiBC amorphous powder,which are then press-molded and heat-treated to fabricate magnetic powder cores(MPCs).By testing the permeability,loss,density,and radial crush strength of MPCs,the effect of the binder on the magnetic properties of the cores is investigated and the best resin is found.The results show that the silicone resin P3 exhibits the best thermal stability,retaining 82.1%of its mass after heat treatment at 430°C.This contributes to improving the insulation of MPCs and reducing the eddy current loss,which is 46.06 mW cm^(−3)(150 kHz,20 mT)with the mechanical strength of 11.13 MPa.The bonding of epoxy resin P4 is superior to that of other resins,which significantly improves the powder compactness and makes MPCs density reach 5.67 g cm^(−3),and its permeability is as high as 28.7.The two types of resins have different advantages,and both lead to MPCs with excellent properties.展开更多
Acidic-and alkalic-hydrolyses are selective in breaking functional bonds and falling off pharmacological moieties of antibiotics in production wastewater in comparison with advanced oxidation processes.Elevating tempe...Acidic-and alkalic-hydrolyses are selective in breaking functional bonds and falling off pharmacological moieties of antibiotics in production wastewater in comparison with advanced oxidation processes.Elevating temperature can accelerate hydrolytic kinetics and improve efficiency.In this work,magnetic sulfonated polypropylene resin(Fe_(3)O_(4)@PS-S)composites were reported for acidic-thermal hydrolysis of tylosin by employing the acidic feature of sulfonic group,the dielectric effect of resin,and the magnetic-loss effect of magnetite under microwave irradiation.As observed,a rapid and complete mitigation 100 mg/L of tylosin was achieved within 15 min by the catalysts.Acidic cleavage of tylosin was fulfilled by sulfonic groups in the composites,and microwave thermal accelerated the hydrolysis reactions due to the dielectric and magnetic-loss effects.Differentiating the dielectric and magnetic-loss effects through electromagnetic analyses indicated that the latter contributed more in converting microwave energy to heat.The interactions under multiple operational conditions were quantitatively fitted using the Behnajady model and visually demonstrated,which indicated that a synergic effect of microwave thermal-and acidichydrolyses contributed to the efficient mitigation of tylosin.The transformation products were identified and the pathways were supposed.Cleaving deoxyaminosugars groups and destructing lactone structures led to reduced antibacterial potential and toxicity reduction.The acute toxicity of tylosin and transformation products to fish,daphnia,and green algae were all classified as non-toxic.This work suggested that this synergistic acid-thermal hydrolytic method is attractive and promising in pretreating tylosin production wastewater in field.展开更多
B-COPNA resin,synthesized from the light fraction of ethylene tar(ETLF),is a superior precursor of the carbon materials.An in-depth understanding of the COPNA resin preparation process and strict control of crosslinki...B-COPNA resin,synthesized from the light fraction of ethylene tar(ETLF),is a superior precursor of the carbon materials.An in-depth understanding of the COPNA resin preparation process and strict control of crosslinking degree are crucial for controlling carbon materials performance.Therefore,the synthesis kinetics of B-COPNA resin prepared from ETLF was investigated using in-situ FTIR in this work.The synthesis kinetic models of B-COPNA resin were established for the first time.To express the kinetic model,the concentration changes of C-H in aromatic rings and O-H in PXG monitored by in-situ FTIR were selected as two indicators to calculate concentration of other compounds and describe the synthesis kinetics.Then confirmatory experiments were conducted,and the ρ^(2)(>0.9900),F-values(>10F_(0.05))and parameter errors(below 3%)of kinetic models verify that concentration changes of C-H and O-H can be used to describe synthesis kinetics of B-COPNA resin.Based on the results of confirmatory experiments,the synthesis kinetic model of B-COPNA resin in the ETLF system is established successfully using concentration changes of O-H as an indicator,whose appropriateness and feasibility are proved by the ρ^(2)(0.9960)and F-values(>10F_(0.05)).These models could accurately describe the synthesis rate of B-COPNA resin.展开更多
We proposed a microscopic mechanical model for the effective elastic modulus of resin mineral composites based on the Mori-Tanaka method and equivalent inclusion theory to predict the elastic modulus of these material...We proposed a microscopic mechanical model for the effective elastic modulus of resin mineral composites based on the Mori-Tanaka method and equivalent inclusion theory to predict the elastic modulus of these materials.The model-predicted values were compared with the experimental results.The results show that when the resin dosage is lower than 10 wt%,the predicted value is lower than the measured value,and the decrease in porosity is obvious;when the resin dosage is higher than 10 wt%,the predicted value is higher than the measured value,the maximum error is 7.95%,and the decrease of porosity is not obvious.The model can predict the trend of the change of elastic modulus.The elastic modulus of resin mineral composites decreases with the increase of porosity.Therefore,the resin dosage should be controlled within 10 wt%when designing the experiments,which provides a guiding direction for the mechanical properties of resin mineral composites to be improved afterward.展开更多
基金financially supported by the Ministry of Science and Higher Education of the Russian Federation。
文摘Carbon-fiber-reinforced plastics(CFRP)with improved mechanical properties based on modified epoxy binders were investigated in this study.By adding 15 parts by weight(p.b.w.)of copolymer of polysulfone with cardo phthalide group(PSFP-70C)to the epoxyanhydride binder,the flexural strength of the epoxy polymer was increased by 60%,the CFRP based on it by 57%,the flexural modulus of the epoxy polymer was increased by 83%,and the composite by 96%.The adhesion strength of the binder to carbon fiber reached a high level at 10 p.b.w.of thermoplastic modifier and increased by 65%compared to the unmodified binder.Scanning electron microscopy(SEM)was used to determine that in epoxyanhydride systems with a polysulfone content of 5–15 p.b.w.,the structure belongs to the"matrix dispersion"type and with a content of 20 p.b.w.to the"interpenetrating phase"type.A heterogeneous structure was also observed using dynamic mechanical analysis.
文摘Composite resin restorations are routinely exposed to acidic and chromogenic beverages that may alter their surface integrity over time.This in-vitro study evaluated the surface roughness behavior of two universal single-shade(Unishade)composites and two conventionalmulti-shade composites following immersion in commonly consumed staining solutions and assessed whether repolishing could restore smoothness after degradation.A total of 120 standardized disc specimens were fabricated and allocated to fourmaterial groups,with each group subdivided into distilled water,cola,and coffee immersion subgroups.Surface roughness was recorded at baseline,after one week,after one month,and following a final repolishing step using a standardized multi-step system.The findings demonstrated that Unishade composites exhibited more stable surface characteristics across all immersion periods,with changes consistently remaining below the threshold associated with biofilm accumulation.Conventional composites showed greater variability,particularly in cola,where roughness values increased significantly compared with distilled water and coffee.Repolishing substantially reduced immersion-induced roughness in all materials,although its effectiveness varied depending on composite formulation and beverage acidity.Cola produced the greatest surface alterations across all groups,highlighting the erosive potential of low-pH beverages.These results indicate that Unishade composites possess superior resistance to surface degradation,likely due to their nano-structured filler configuration and less hydrophilic resin matrices,while conventional materials appear more susceptible to acidic challenge.Within the limitations of this study,selecting surface-stable material types and applying appropriate finishing and repolishing protocols may enhance the long-term performance and esthetics of composite restorations.
基金funded by Large-Scale Instrument and Equipment Sharing Service Platform of College of Chemistry,Chemical Engineering and Resource Utilization,NEFUsupported by the National Natural Science Foundation of China(Grant No.52273066)Undergraduate Training Programs for Innovations by Heilongjiang Province[grant number S202510225421].
文摘Phenolic resins are widely used in thermal protection,yet achieving simultaneous improvement in thermal stability and mechanical strength remains challenging.In this work,a vinyl-modified silicone resin(VMTQ)was synthesized and incorporated into a boron phenolic resin(BPF)matrix.Three composite ceramic fillers,Al_(2)O_(3)-SiO_(2)-ZrO_(2)(ASZ),Al_(2)O_(3)-SiO_(2)-TiO_(2)(AST),and Al_(2)O_(3)-SiO_(2)-MgO(ASM),were further introduced to construct a multi-oxide synergistic reinforcement system.Thermogravimetric analysis shows that the maximum decomposition rate decreases by 0.2-0.3%⋅min^(-1),while the ASM/V3/BPF-3 composite exhibits a 74.53%increase in char yield at 800℃and a 163.3℃increase in initial decomposition temperature,confirming its significantly enhanced thermal stability.SEM/EDS and XRDanalyses reveal thatASZ,AST,and ASM promote the formation of stable ceramic phases,withASM generating the densest MgO-Al_(2)O_(3)-SiO_(2)composite oxide layer.Mechanical testing demonstrates that ASZ improves vertical impact strength by 23.9%,AST increases parallel impact strength by 14.1%,andASMenhances bending strength by 34.5%(316.8 MPa).These results clearly indicate that the combination of VMTQ modification with multi-oxide ceramic fillers can effectively elevate both the thermal stability and mechanical performance of BPF-based composites,providing a practical pathway for designing high-performance resins for demanding thermal-environment applications.
基金financially supported by the Science and Technology Innovation Development Program of Jilin City(Nos.20240103013 and 20240103012)the Jilin Province Key Breakthrough Special Project(No.2025JLGJ0015GX)the Open Project of the State Key Laboratory of Inorganic Synthesis and Preparative Chemistry(No.202527)at Jilin University.The authors acknowledge the assistance of the Jilin Institute of Chemical Technology Center of Characterization and Analysis.We also thank Pro.Jie Chen with the help of SEM characterization.
文摘Poly(aryl ether sulfone)with fatty-acid side chains that crosslink with epoxy resin improves the interfacial compatibility between poly(aryl ether sulfone)and epoxy resin.Hydroxyl-terminated phenolphthalein-based poly(aryl ether sulfone)(PPES-OH)was blended with fatty-acid side-chain-modified phenolphthalein-based poly(aryl ether sulfone)(PPES-TA),with the goal of further enhancing the toughening effect on epoxy resin.In this study,PPES-OH,PPES-TA,and a composite poly(aryl ether sulfone)(PESP-TA)were synthesized.Their molecular structures and thermal properties were characterized using proton nuclear magnetic resonance spectroscopy(1H-NMR spectroscopy),thermogravimetric analysis(TGA),and differential scanning calorimetry(DSC).Subsequently,PPES-OH,PPES-TA,and PESP-TA were introduced into the anhydride-cured epoxy system to evaluate their toughening effects on epoxy resin.The curing behavior of the epoxy resin blends was investigated using DSC,which also enabled the exploration of the corresponding curing mechanisms.The thermal and mechanical properties of the toughened systems were characterized.Scanning electron microscopy(SEM)was used to observe the impact fracture surfaces of the resin,which revealed‘fish-scale’structures and shear bands in the resin system after curing.These findings demonstrate that similar thermoplastic chains become entangled with one another,forming additional physical cross-links.This enhanced the interfacial compatibility between the thermoplastic and thermoset resins,which,in turn,significantly improved the impact toughness and elongation at break of the system.In summary,PESP-TA has emerged as a reactive thermoplastic toughening agent that is feasible for preparation and has significant practical application potential.
基金supported by the National Natural Science Foundation of China(Grant Nos.51991351 and51903132)the Young Elite Scientist Sponsorship Program by CAST(No.2022QNRC001).
文摘Different reactive flame retardants have been extensively developed for vinyl ester resins(VERs),but very few of them can yield a flame-retardant resin that meets defined standards(e.g.UL-94 V-0 rating).In this work,phosphorous-containing 1-vinylimidazole salts(called VIDHP and VIDPP)were synthesized through the facile neutralization of the acid and 1-vinylimidazole.VIDHP and VIDPP were then applied as flame-retardant crosslinking agents of VERs,by which phosphorus-containing groups could be incorporated into the resin chain via ionic bonds.VIDHP/VER and VIDPP/VER showed a high curing activity and can be well cured in moderate temperatures.With 20 wt.%additions of VIDHP and VIDPP,VIDHP20/VER,and VIDPP20/VER presented a limiting oxygen index value of 29.7%and 28.4%,respectively,with the latter achieving a UL 94 V0 rating.In the cone calorimetric test,compared to the unmodified VERs,VIDPP20/VER exhibited large reductions in the peak heat release rate,total heat release rate,and total smoke release rate while VIDHP20/VER demonstrated comparatively inferior performance in terms of the heat release.VIDHP20/VER and VIDPP20/VER showed good thermal stability and presented a little lower glass transition temperature than the control sample.VIDPP with a low phosphorus oxidation state(+1)demonstrated high flame-retardant activities in the gaseous phase,whereas VIDHP with a high phosphorus oxidation state(+5)primarily exhibited efficacy in the condensed phase.
基金funded by the Latvian State Institute of Wood Chemistry Bioeconomic grant no.04-24“Development of Composites from Polymer Resin Synthesized from Tall Oil Fatty Acids and Reinforced with Various Fillers”(FiTeCo).
文摘Studies on the use of renewable materials for various applications,including polymers,have gained momentum due to global climate change and the push towards a circular economy.In this study,polymer resins were developed through Michael 1,4-addition.The precursors were synthesized from tall oil-based acetoacetates derived from epoxidized tall oil fatty acids or their methyl esters.Two different epoxidation methods were employed:enzymatic epoxidation of tall oil fatty acids and ion-exchange resin epoxidation of tall oil fatty acid methyl esters.Following oxirane opening and transesterification with trimethylolpropane,further esterification or transesterification was carried out to obtain the acetoacetates.These synthesized acetoacetates were then reacted with acrylates of various functionalities to obtain polymer resins with differing degrees of crosslinking.The developed polymer resins were characterized using differential scanning calorimetry,dynamic mechanical analysis,and thermogravimetric analysis.The results indicated that the glass transition temperature and storage modulus of the polymer resins were significantly influenced by both the functionality of the acrylates used and the epoxidation technique employed.Higher acrylate functionality resulted in increased stiffness,while enzymatic epoxidation enhanced the polymer’s mechanical properties,nearly doubling the storage modulus,achieving approximately 470 MPa,compared to the ion-exchange resin technique.Therefore,selecting the appropriate acrylate functionality and epoxidation method could tailor the mechanical properties of the polymer resins.
基金financially supported by the National Natural Science Foundation of China(No.52377025)。
文摘The introduction of dynamic covalent bonds into the structure of epoxy resins can improve the degradation performance of the materials.But to a certain extent,it will affect the insulating properties of the resin,and how to balance the insulating properties and degradation performance has become an urgent problem.In this paper,the effects of different catalysts on the thermal-force-electrical properties of sorbitolbased resins were systematically investigated based on the dynamic ester bonding to construct the resin crosslinking network,and the biobased sorbitol glycidyl ether was used as the resin matrix.The experiments show that the resin system catalyzed by triethanolamine(TEOA)exhibits excellent comprehensive performance,which combines good thermal stability and mechanical properties with excellent electrical properties(breakdown field strength of 44.21 k V/mm and dielectric loss factor of 0.29%).In addition,chemical degradation tests were conducted on the resin systems with different catalysts,and the experiments showed that the produced resins could be degraded in benzyl alcohol and exhibited good degradation performance.This study provides a theoretical basis and technical path for the development of new bio-based electrical insulating materials with both high insulation and degradation properties,which is conducive to the popularization and application of bio-based resins in the field of electrical equipment.
基金financially supported by the National Natural Science Foundation of China(No.U23A20691)Innovation Group of National Ethnic Affairs Commission of China(No.MZR20006)+2 种基金Fund for Academic Innovation Teams of SouthCentral Minzu University(No.XTZ24012)Fundamental Research Fund for the Central Universities of South-Central Minzu University(Nos.CZD24001 and CZQ25012)Scientific Research Fund of South-Central Minzu University(No.YZY25007)。
文摘The poor degradability and limited recyclability of epoxy resins are key challenges hindering the efficient recycling of ex-service wind turbine blades(EWTBs).Herein,we proposed a selective degradation strategy for direct recycling and high-value recovery of epoxy resins by introducing degradable Schiff base groups into the molecular structure and utilizing the resulting oligomers as curing agents.To realize this strategy,a series of Schiff base compounds were synthesized using bio-based vanillin and diamines and subsequently functionalized with epichlorohydrin to yield bio-based epoxy resins.The cured epoxy resins demonstrated remarkable improvements in the mechanical properties of diglycidyl ether of bisphenol-A(DGEBA),with an increases of 44.49%in the tensile strength of 38.55%,bending strength,and impact strength of 71.20%.The introduction of dynamic Schiff base bonds enabled the selective degradation of the vanillin-2,2-bis[4-(4-aminophenoxy)phenyl]propane-based epoxy resin(VBEP)/DGEBA copolymer,producing 84.20% oligomers that can be directly recycled and reused.Replacing 30 wt% of the curing agent with the oligomer increased the tensile strength of the cured sample to 75.40 MPa,surpassing that of the cured DGEBA.Under simulated acid rain and seawater exposure,the copolymer exhibited a service life of 27 years at 40℃,significantly exceeding the currently reported service life of 20 years.This study presents a sustainable strategy for the direct recycling and high-value reuse of epoxy resin,offering a promising solution for EWTBs.
基金supported by the National Key Research and Development of China(No.2018YFA0702804).
文摘Over the past several decades,the integration of IONs into EP emerged as an effective method for enhancing its mechanical properties.Nevertheless,challenges remain,especially with u-IONs,where the interfacial strength with EP is suboptimal,resulting in aggregation within the EP matrix and a subsequent deterioration in the mechanical performance of u-ION/EP nanocomposites.In this comprehensive review,we explored advanced chemical modification techniques tailored for IONs incorporated into EP,providing a detailed examination of the mechanical characteristics of surface cm-ION/EP nanocomposites.This review investigates various chemical modification methods and their distinct impacts on the mechanical attributes of the resulting EP nanocomposites.Special emphasis is given to addressing the persistent challenges of inadequate interfacial strength and aggregation.Furthermore,this article examines prospective surface modification approaches for inorganic oxide nanoparticles,offering a visionary outlook on methods to improve the mechanical performance of EP in future.
文摘It is a good practice to change the site soil properties when dealing with inappropriate soils in geotechnical engineering,referred to as soil improvement.This study investigated the effects of epoxy resin LR202 stabilizer(5 wt%of soil as an optimum percentage)and glass fibers(0 wt%,0.4 wt%and 0.8 wt%of stabilized soil)as reinforcement on silty sand’s durability.For this purpose,the unconfined compressive strength test(12 tests),durability test(12 tests),ultrasonic pulse velocity(UPV)test(48 tests),and standard compactions test(5 tests)were performed.The results of this study showed that the addition of epoxy resin improves the durability of silty sand soil.The stabilized samples containing 5 wt%epoxy resin resisted 12 freeze-thaw cycles,and the sample behavior was enhanced by adding 0.4 wt%and 0.8 wt%fibers to the stabilized samples.Hence,the samples stabilized with epoxy resin exhibited acceptable behavior under freeze-thaw durability cycles.This indicates that epoxy resin stabilizer is appropriate in areas with possible frost and exhibits good behavior.The results of the UPV test showed that it could be used as a non-destructive test to control the durability of epoxy resin-stabilized soils.
基金Funded by the Fundamental Research Funds for the Central Universities(WUT:2023III012JL)。
文摘We aimed to enhance the flame retardancy of epoxy resin(EP)by synthesizing a novel,halogen-free flame retardant through a one-pot method.The synthesis utilized 9,10-dihydro-9-oxa-10-phospha-phenanthrene-10-oxide(DOPO),furfurylamine(FA),and benzene propionaldehyde(BPA)as raw materials.We conducted differential scanning calorimetry(DSC)analysis to investigate the effects of FPD on the curing process and thermal properties of EP.Our findings reveal that incorporating FPD into EP can facilitate a faster curing process and increase the carbon residue post-combustion.Specifically,the FPD/EP-7 composite demonstrates a limiting oxygen index(LOI)of 34.9%and achieves a UL-94V-0 rating with a phosphorus content of 0.91wt%.These results indicate that FPD significantly enhances the thermal stability and charring rate of EP,thereby improving its flame retardancy.Although the addition of FPD slightly reduces the mechanical properties of EP,the composite material maintains excellent performance.
基金financial support of the National Natural Science Foundation of China(No.42230706)the Outstanding Youth Science Fund(Overseas)of Shandong Provincial Natural Science Foundation(No.2022HWYQ-015)+1 种基金the Taishan Scholars Project Special Fund(No.tsqn202211039)Qilu Youth Talent Program of Shandong University(No.61440082163171)。
文摘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.
基金supported by the National Natural Science Foundation of China(No.52173264)the Natural Science Foundation Project of Chongqing(No.cstc2024ycjh-bgzxm0005)+1 种基金the Fundamental Research Funds for the Central Universities(No.SWU-XDJH202314)The authors thanks Dr.Xi Tang in Southwest University for the technical support in the use of the vector network analyzer.
文摘Plastic waste recycling is a focal point in today's sustainable development efforts.Improper disposal can lead to secondary pollution,posing threats to the environment and human health.In this study,we aim to recycle waste epoxy resin and glass fiber-reinforced epoxy resin composites via an electroless plating and a carbonization process,to design high-value-added carbon materials for microwave absorption.By pulverizing solid waste and introducing magnetic metal nanoparticles onto its surface,a composite carbon material capable of excellent microwave absorption performance was successfully developed.Specifically,doping nickel particles into carbon materials derived from glass fiber/epoxy resin achieved a wide effective absorption bandwidth(EAB)of 5.9 GHz with a matching thickness of 1.9 mm,covering nearly the entire Ku band,and achieving a minimum reflection loss(RLmin)of−36 dB simultaneously.The superior absorption performance is attributed to multiple reflections or scattering of electromagnetic waves within the material,as well as conduction and magnetic losses,dipole and interfacial polarization effects.These results demonstrate that through rational design and optimization,waste epoxy and waste glass fiber-reinforced epoxy resin-based composite materials can be effectively recycled into high-performance microwave absorbing materials,offering a straightforward and efficient pathway for waste resource utilization.
基金funded by the Beijing Nature Sciences Fund Haidian Originality Cooperation Project (Grant No. L212002)。
文摘In the production of castings,intrusive gas pore represents a kind of common defects which can lead to leakage in high gas-tightness requirement castings,such as cylinder blocks and cylinder heads for engines.It occurs due to the intrusion of gases generated during the resin burning of the sand core into castings during the casting process.Therefore,a gas generation and flow constitution model was established,in which the gas generation rate is a function of temperature and time,and the flow of gas is controlled by the gas release,conservation,and Darcy's law.The heat transfer and gas flow during casting process was numerically simulated.The dangerous point of cores is firstly identified by a virtual heat transfer method based on the similarity between heat transfer and gas flow in the sand core.The gas pores in castings are predicted by the gas pressure,the viscosity and state of the melt for these dangerous points.Three distinct sand core structures were designed and used for the production of iron castings,and the simulated gas pore results were validated by the obtained castings.
基金financially supported by the National Key Research and Development Program of China(No.2023YFB3812500)the National Natural Science Foundation of China(No.52105003)the Beijing Municipal Natural Science Foundation(No.2222058)。
文摘Bioinspired active pillar structures,known for their large surface area,mechanical compliance,and diverse deformation modes,have garnered extensive research interest.Among various active pillar structures,liquid crystal elastomer(LCE)pillar arrays are capable of exhibiting significant and reversible anisotropic deformation under cyclic heating and cooling,showing great potential in tunable adhesion,soft robots,and biomedical devices.However,scaling up LCE pillar manufacturing remains challenging,limiting its practical applications.In this work,a solventfree LCE resin is developed with unique features including simple operating procedure,short fabrication time,and tunable responsive temperature,enabling rapid and large-scale production of LCE pillar arrays.The LCE resin allows for the preparation of complex 3D shapes in addition to film or specimen.The fabrication time can be as short as 4 h,without the need to evaporate solvent.Moreover,the LCE resins can be adjusted with a variable phase transition temperature range from 49.4℃ to 97.7℃ by incorporating non-liquid crystal acrylate chains.The resulting active pillar array structure can undertake sequential actuation upon heating with the tunable actuation temperature.Finally,the application of these pillar arrays in multi-level information encryption is demonstrated.The LCE pillar structure introduced here offers a new strategy for constructing advanced active LCE structures with tunable responsive behavior.
文摘BACKGROUND Due to saliva and salivary glands are reservoir to severe acute respiratory syndrome-coronavirus 2(SARS-CoV-2),aerosols and saliva droplets are primary sources of cross-infection and are responsible for the high human–human transmission of SARS-CoV-2.However,there is no evidence about how SARSCoV-2 interacts with oral structures,particularly resin composites.AIM To evaluate the interaction of SARS-CoV-2 proteins with monomers present in resin composites using in silico analysis.METHODS Four SARS-CoV-2 proteins[i.e.main protease,3C-like protease,papain-like protease(PLpro),and glycoprotein spike]were selected along with salivary amylase as the positive control,and their binding affinity with bisphenol-A glycol dimethacrylate,bisphenol-A ethoxylated dimethacrylate,triethylene glycol dimethacrylate,and urethane dimethacrylate was evaluated.Molecular docking was performed using AutoDock Vina and visualised in Chimera UCSF 1.14.The best ligand–protein model was identified based on the binding energy(ΔG–kcal/moL).RESULTS Values for the binding energies ranged from-3.6 kcal/moL to-7.3 kcal/moL.The 3-monomer chain had the lowest binding energy(i.e.highest affinity)to PLpro and the glycoprotein spike.Non-polymerised monomers and polymerised chains interacted with SARS-CoV-2 proteins via hydrogen bonds and hydrophobic interactions.Those findings suggest an interaction between SARS-CoV-2 proteins and resin composites.CONCLUSION SARS-CoV-2 proteins show affinity to non-polymerised and polymerised resin composite chains.
基金financially supported by the Key research and development project of Shandong province in China(Grant No.2022CXGC020308).
文摘Four types of resins,P1–P4,are used as binders for FeSiBC amorphous powder,which are then press-molded and heat-treated to fabricate magnetic powder cores(MPCs).By testing the permeability,loss,density,and radial crush strength of MPCs,the effect of the binder on the magnetic properties of the cores is investigated and the best resin is found.The results show that the silicone resin P3 exhibits the best thermal stability,retaining 82.1%of its mass after heat treatment at 430°C.This contributes to improving the insulation of MPCs and reducing the eddy current loss,which is 46.06 mW cm^(−3)(150 kHz,20 mT)with the mechanical strength of 11.13 MPa.The bonding of epoxy resin P4 is superior to that of other resins,which significantly improves the powder compactness and makes MPCs density reach 5.67 g cm^(−3),and its permeability is as high as 28.7.The two types of resins have different advantages,and both lead to MPCs with excellent properties.
基金supported by the National Natural Science Foundation of China(Nos.51978052 and 22306012)the National Key Research and Development Program of China(No.2023YFC3711300)the Guangdong Basic and Applied Basic Research Foundation(No.2022A1515110578).
文摘Acidic-and alkalic-hydrolyses are selective in breaking functional bonds and falling off pharmacological moieties of antibiotics in production wastewater in comparison with advanced oxidation processes.Elevating temperature can accelerate hydrolytic kinetics and improve efficiency.In this work,magnetic sulfonated polypropylene resin(Fe_(3)O_(4)@PS-S)composites were reported for acidic-thermal hydrolysis of tylosin by employing the acidic feature of sulfonic group,the dielectric effect of resin,and the magnetic-loss effect of magnetite under microwave irradiation.As observed,a rapid and complete mitigation 100 mg/L of tylosin was achieved within 15 min by the catalysts.Acidic cleavage of tylosin was fulfilled by sulfonic groups in the composites,and microwave thermal accelerated the hydrolysis reactions due to the dielectric and magnetic-loss effects.Differentiating the dielectric and magnetic-loss effects through electromagnetic analyses indicated that the latter contributed more in converting microwave energy to heat.The interactions under multiple operational conditions were quantitatively fitted using the Behnajady model and visually demonstrated,which indicated that a synergic effect of microwave thermal-and acidichydrolyses contributed to the efficient mitigation of tylosin.The transformation products were identified and the pathways were supposed.Cleaving deoxyaminosugars groups and destructing lactone structures led to reduced antibacterial potential and toxicity reduction.The acute toxicity of tylosin and transformation products to fish,daphnia,and green algae were all classified as non-toxic.This work suggested that this synergistic acid-thermal hydrolytic method is attractive and promising in pretreating tylosin production wastewater in field.
基金financially supported by the National Natural Science Foundation of China(52174023)National Natural Science Foundation of P.R.China(22308104)China Petroleum Engineering Corp.,Ltd.(CPEC)(2021ZYGC-01-01)。
文摘B-COPNA resin,synthesized from the light fraction of ethylene tar(ETLF),is a superior precursor of the carbon materials.An in-depth understanding of the COPNA resin preparation process and strict control of crosslinking degree are crucial for controlling carbon materials performance.Therefore,the synthesis kinetics of B-COPNA resin prepared from ETLF was investigated using in-situ FTIR in this work.The synthesis kinetic models of B-COPNA resin were established for the first time.To express the kinetic model,the concentration changes of C-H in aromatic rings and O-H in PXG monitored by in-situ FTIR were selected as two indicators to calculate concentration of other compounds and describe the synthesis kinetics.Then confirmatory experiments were conducted,and the ρ^(2)(>0.9900),F-values(>10F_(0.05))and parameter errors(below 3%)of kinetic models verify that concentration changes of C-H and O-H can be used to describe synthesis kinetics of B-COPNA resin.Based on the results of confirmatory experiments,the synthesis kinetic model of B-COPNA resin in the ETLF system is established successfully using concentration changes of O-H as an indicator,whose appropriateness and feasibility are proved by the ρ^(2)(0.9960)and F-values(>10F_(0.05)).These models could accurately describe the synthesis rate of B-COPNA resin.
基金Funded by Demonstration Platform for the Production and Application of Key Materials for High-grade CNC Machine Tools(No.2020-370104-34-03-043952)。
文摘We proposed a microscopic mechanical model for the effective elastic modulus of resin mineral composites based on the Mori-Tanaka method and equivalent inclusion theory to predict the elastic modulus of these materials.The model-predicted values were compared with the experimental results.The results show that when the resin dosage is lower than 10 wt%,the predicted value is lower than the measured value,and the decrease in porosity is obvious;when the resin dosage is higher than 10 wt%,the predicted value is higher than the measured value,the maximum error is 7.95%,and the decrease of porosity is not obvious.The model can predict the trend of the change of elastic modulus.The elastic modulus of resin mineral composites decreases with the increase of porosity.Therefore,the resin dosage should be controlled within 10 wt%when designing the experiments,which provides a guiding direction for the mechanical properties of resin mineral composites to be improved afterward.
