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
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
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
Silicon-containing arylacetylene (PSA) resins have broad application prospects because of their excellent heat resistance.However,improving their mechanical properties and interfacial bonding with reinforcement fibers...Silicon-containing arylacetylene (PSA) resins have broad application prospects because of their excellent heat resistance.However,improving their mechanical properties and interfacial bonding with reinforcement fibers while maintaining heat resistance is a challenge in engineering applications.Here,poly(diethynylbenzene-methylsilyl-3-benzonitrile)(DEB-CN) and poly(diethynylbenzene-methylsilyl-3,6-diethynylcarbazole-3-benzonitrile)(DEC-CN) were synthesized via an isopropylmagnesium chloride lithium-chloride complex (i-PrMgCl·LiCl),overcoming the compatibility problem between cyano groups and Grignard reagents.The cyano and alkyne groups in the resin underwent cyclization to form pyridine,catalyzed by the-NH-moiety in DEC-CN,resulting in extremely high thermal stability (5%weight loss temperature:669.3°C,glass transition temperature>650°C).The combination of cyano dipole-dipole pairing and hydrogen bonding greatly enhanced the resin-fiber interface properties,while the generated pyridine promoted stress relief in the crosslinked network,substantially improving the mechanical properties of the cyano-silicon-containing arylacetylene resin composites.The flexural strength of quartz fiber cloth/DEC-CN composites was 298.2 MPa at room temperature and 145.9 MPa at 500°C,corresponding to 84.0%and 127.6%enhancements,respectively,over the cyano-free counterpart.These cyano-silicon-containing arylacetylene resins exhibited a dual reinforcement mechanism involving physical interfacial interactions and chemical crosslinking,achieving a good balance between thermal stability and mechanical properties.展开更多
Fast pyrolysis of pre-treated birch wood in a super-heated steam environment produces a condensate rich in anhydrosugars.With the objective to obtain several product streams from this condensate,the possibility of ext...Fast pyrolysis of pre-treated birch wood in a super-heated steam environment produces a condensate rich in anhydrosugars.With the objective to obtain several product streams from this condensate,the possibility of extracting additional chemical species is explored,thus promoting the development of a pyrolysis-based biorefinery.In this work,the extraction and recovery of pyrolytic phenols from birch wood pyrolysis condensate was studied using ion exchange resins.With an aim to achieve effective phenol recovery,while obtaining high purity levoglucosan,basic ion exchange resins,both in OH−and Cl^(−)form,as well as polystyrene-divinyl resins without functional groups were compared.This study characterizes the influence of sorbent matrix type and porosity,functional group and counter ion on the sorption of various aromatic compounds.It was concluded that the counter ion of the ion exchange resins had the most influence on the pyrolytic phenol adsorption,while in the case of unfunctionalized resins smaller pore size improved removal of phenols from the pyrolysis liquids.Of the resins tested,the most effective at the removal and recovery of pyrolytic phenols were strongly basic,macroporous,anion exchange resins in OH^(−)form.The possibility to reuse the sorbents and solvents is explored to make the over-all process more environmentally friendly and economically feasible.展开更多
Bisphenol A (BPA) is the primary chemical used in the production of epoxy resins but as of today is not widely available in a bio-based form. BPA is also classified as a substance of very high concern due to its repro...Bisphenol A (BPA) is the primary chemical used in the production of epoxy resins but as of today is not widely available in a bio-based form. BPA is also classified as a substance of very high concern due to its reproductive toxicity and endocrine-disrupting effects. Phlorotannins, a type of polyphenols, offer a promising structural alternative to bisphenol A as a more sustainable option. They are found in high quantities in brown algae, which are already harvested for alginate production. As a result, phlorotannins present an under-researched yet promising marine resource for the chemical industry, particularly in the area of epoxy resin formulation. In this study, a model epoxy resin compound based on phloroglucinol, the simplest phlorotannin, was chosen to explore its reactivity and the thermo-mechanical properties of epoxy resins based thereof. As hardeners well-established systems like isophorone diamine for ambient temperature cure as well as heat-curing anhydrides and dicyandiamide were used. Across all cases, thermosets with glass transition temperatures above 100?C were achieved under cross-linking conditions similar to those used today. One phthalic anhydride derivative yielded a glass transition temperature of 198?C, highlighting the significant potential of these algae-based epoxy resins for industrial uses, such as impregnating resins for fiber-reinforced plastics.展开更多
Mango seed and palm oils were modified by alcoholysis and esterification process, to form alkyd resin, which is generally used in surface coatings and adhesives. N-hexane was used to extract the mango seed oil, while,...Mango seed and palm oils were modified by alcoholysis and esterification process, to form alkyd resin, which is generally used in surface coatings and adhesives. N-hexane was used to extract the mango seed oil, while, palm oil was manually isolated by pressing method after heating to softness. Some physio-chemical properties, like, percentage yield, saponification value, acid value, iodine value, refractive index, etc., were carried out according to standards to determine the suitability of the oils in bio-resin synthesis. The colour intensity of the alkyd resins were tested using Gardner scale, elasticity by viscometer, hardness, chemical resistance, and other properties of the alkyd resin were tested according to standard. The Infra-Red (IR) spectra of the raw oils and their respective alkyd resins were determined before modification. Palm oil alkyd resin exhibited a characteristic straight chain of ester functional group at 1738.64 cm−1 and aromatic (C=C) ring of ester at 1730.09 cm−1 while, mango seed oil alkyd resin showed spectrum of strong peaks at 11698 cm−1 with stretching frequency to 1240 cm−1, 1221 cm−1, 1188 cm−1, indicating the presence of a carbon atom single bonded to oxygen. The hardness, glossy tests, drying time, chemical resistance, etc., of the sample alkyd resins compared well to the commercial grade alkyd resin.展开更多
A new kind of modified thermoset resins were synthesized by phase-transfer Williamson reaction from novolac resin and mixtures of allyl- and propargyl-chlorides. The compositions of the resins were defined by 1H NMR ...A new kind of modified thermoset resins were synthesized by phase-transfer Williamson reaction from novolac resin and mixtures of allyl- and propargyl-chlorides. The compositions of the resins were defined by 1H NMR (nuclear magnetic resonanse) spectroscopy and the dependence of the cured materials properties on the composition was established. Increase of a propargyl content resulted in char yield raise and the maximum value had been found for propargylated resin--58%. DSC (differential scanning calorimetry)-analysis of the resins has demonstrated that exothermic enthalpy of the curing process could be adjusted by varying the content of propargyl and allyl groups in the resin.展开更多
In the present study we prepared macroporous polyvinyl alcohol beads. A series of bilirubin adsorbents were generated by immobilization of eight amine agents to the beads as ligands. The adsorption of bilirubin was ev...In the present study we prepared macroporous polyvinyl alcohol beads. A series of bilirubin adsorbents were generated by immobilization of eight amine agents to the beads as ligands. The adsorption of bilirubin was evaluated by in vitro static and dynamic adsorption tests. The results show that these adsorbents have excellent adsorption efficiency and capacity. Among the eight ligands, trimethylamine (TMA), triethylamine (TEA) and 1,6- hexanediamine (HDA) showed the highest adsorption capacity. The adsorption equilibrium can be achieved in half an hour, and the adsorption percentage of bilirubin was up to 80%. Static electricity and hydrophobie interaction played the main role in bilirubin adsorption, and the adsorption was found to match the monolayer model. The excellent adsorption of these adsorbents indicates their potential in clinical treatment.展开更多
By means of the synthetic approach of non-polar or weak polar oil-sorbed polymers,the gel sorption resin(GSR) and the multiporous sorption resin(MSR) were prepared.The structure of the resins,sorption power...By means of the synthetic approach of non-polar or weak polar oil-sorbed polymers,the gel sorption resin(GSR) and the multiporous sorption resin(MSR) were prepared.The structure of the resins,sorption power,sorption speed,desorption,and sorption of organic compounds from sewage,exhaust gas and soil were discussed.Moreover,the resins were used to decrease LOD and BOD5 values of water waste from sewage factory.Theyare a klndof potential materials for environmental control.展开更多
Resins of complexes made from agarose-Ce4+ (RCA-Ce) and chitosan-Ce4+ (RCC-Ce) were prepared. Hydrolysis rates of methamidophos, omethoate and chlorpyrifos treated by RCA-Ce were 32.39%, 27. 12% and 46.62%, respective...Resins of complexes made from agarose-Ce4+ (RCA-Ce) and chitosan-Ce4+ (RCC-Ce) were prepared. Hydrolysis rates of methamidophos, omethoate and chlorpyrifos treated by RCA-Ce were 32.39%, 27. 12% and 46.62%, respectively, those of chlorpyrifos and methamidophos in mung bean sprout juice 38.28% and 35.45% , and that of chlorpyrifos in tea extract 59.76% . Hydrolysis rates of protein in tea extract treated by RCA-Ce increased by 86.46% . RCC-Ce could be employed in the apple juice production. The contents of methamidophos and parathion-methyl in the juice treated by RCC-Ce decreased 58.76% and 71.92% . Furthermore, RCC-Ce was used to clarification for beer by the ways of a column. RCC-Ce could hydrolyze sensitive protein and increase contents of free amino acid in the beer. Therefore, the beer treated by RCC-Ce could stay oxidation and aging procedure due to some metal ions being absorbed by RCC-Ce.展开更多
With the urgent shortage of forest resource in China, using agro-residues as raw materials of composite become increasingly important. Agro-residue is the most potential fiber resource, which is helpful to sustainable...With the urgent shortage of forest resource in China, using agro-residues as raw materials of composite become increasingly important. Agro-residue is the most potential fiber resource, which is helpful to sustainable development of composite industries in China. Based on a great deal of researches, this paper summarized and discussed some problems in using agro-residues as raw materials of composites, including raw material preparation, hot-pressing, bonding technology, preventing composite from going moldy. It is proposed that to manufacture the composite of rice straws or wheat straws, the isocayante resin is a suitable adhesive, and the appropriate technologies, bonding, and treatment measures are also needed.展开更多
Aim To prepare the prolonged-released microspheres of mefformin hydrochloride. Methods Ion-exchange resin-drug mefformin hydrochloride complexes were prepared as core materials, and followed by coating using ethylcell...Aim To prepare the prolonged-released microspheres of mefformin hydrochloride. Methods Ion-exchange resin-drug mefformin hydrochloride complexes were prepared as core materials, and followed by coating using ethylcellulose (EC) by the emulsion solvent diffusion technique. The release rate of mefformin from the microcapsules was highly dependent on the encapsulating formulation, thus being used as an index for formulation screening. Orthogonal experiments were performed to optimize the coating formulation. Results The final chosen formulation for coating of mefformin microcapsules were as follows: ( 1 ) the ratio of EC (20cps) to EC (45cps) was 50:50; (2) the ratio of plasticizer to coating materials was 20% ;and (3) the ratio of resin-mefformin complexes to coating materials was 5 : 1. Conclusion The prolonged release microspheres of mefformin hydrochloride were successfully prepared.展开更多
This study assessed the adsorption process and the reaction kinetics involved in the selective recovery of vanadium from an acid solution containing iron as an impurity.Four commercial resins were studied:Lewatit^(...This study assessed the adsorption process and the reaction kinetics involved in the selective recovery of vanadium from an acid solution containing iron as an impurity.Four commercial resins were studied:Lewatit^(®)MonoPlus TP 209 XL,Lewatit^(®) TP 207,Dowex^(TM)M4195(chelating resin)and Lewatit^(®) MonoPlus S 200 H(strong cationic exchange resin).To investigate the effect of time on the adsorption process,batch experiments were carried out using the following initial conditions:pH 2.0,298 K,and a proportion of 1 g of resin to 50 mL of solution.The variation of pH over time was analyzed.Chelating resin released less H+ions as the adsorption occurred,resulting in a lower drop of pH when compared to S 200 H resin.Ion adsorption by the resins was also evaluated through FT-IR and SEM−EDS before and after the experiments.Among the evaluated kinetic models(pseudo-first order,pseudo-second order,Elovich and intraparticle diffusion models),the pseudo-second order model best fits the experimental data of the adsorption of vanadium and iron by all of the four resins.M4195 resin showed the highest recovery of vanadium and the lowest adsorption of iron.Kinetic data,which are fundamental to industrial processes applications,are provided.展开更多
A solid-phase extraction resin SIRs-P227/XAD-7 HP was prepared by impregnating extractant P227 onto macroporous resin XAD-7 HP beads. SIRs-P227/XAD-7 HP beads were characterized by Fourier transform infrared spectrosc...A solid-phase extraction resin SIRs-P227/XAD-7 HP was prepared by impregnating extractant P227 onto macroporous resin XAD-7 HP beads. SIRs-P227/XAD-7 HP beads were characterized by Fourier transform infrared spectroscopy(FTIR) and scanning electron microscopy(SEM) equipped with energy-dispersive spectroscopy(EDS). The adsorption kinetics, particle size effect,adsorption isotherm, pH_(equilibrium)–lg D relationship(where D is distribution coefficient), desorption, adsorption selectivity for heavy rare earths, and impurity ions were studied. The results showed that the adsorption kinetics of Lu(III) on the SIRs-P227/XAD-7 HP beads fitted the Morris–Weber model best. The adsorbance decreased as the particle size increased. The pH_(equilibrium)–lg D relationship fitted well with a straight line, and the slope was 1.56. The experimental data fitted well with Langmuir adsorption.The calculated maximum adsorption capacity was23.8 mg·g^(-1), while the experimental datum was22.7 mg·g^(-1) at the given conditions. The adsorbed Lu(III)can be easily stripped by 0.1 mol·L^(-1) HCl. The adsorption selectivity of SIRs-P227/XAD-7 HP for heavy REs exhibited the following order: Lu>Yb>Tm>Er>Ho. The adjacent heavy rare earth(RE) separation factors β_(Lu/Yb),β_(Yb/Tm), β_(Tm/Er), and β_(Er/Ho)were 1.57, 3.00, 3.03, and 2.23,respectively, at liquid/solid ratio(L/S) equal to 3:20. The adsorption selectivity for impurity ions exhibited the followingorder:Fe >Lu>Tm>Zn>Mg>Ca>Ho>Co>Ni>Cu>Al.展开更多
2-Acryloxyacetophenone (AAP) was prepared and subjected to suspension polymerization with methyl methacrylate (MMA) using azobisisobutyronitrile (AIBN) as free radical initiator. The differently sulfonated AAP-M...2-Acryloxyacetophenone (AAP) was prepared and subjected to suspension polymerization with methyl methacrylate (MMA) using azobisisobutyronitrile (AIBN) as free radical initiator. The differently sulfonated AAP-MMA cross-linked copolymer cationic exchange resins were prepared by sulfonation with concentrated sulphuric acid at 70 ~C. Several characteristics of the prepared resins were evaluated, i.e. FTIR, the ion-exchange capacity (IEC), thermo gravimetric analysis (TGA), particle size distribution and microscopic morphology. The resin characteristics were altered with degree of sulfonation, providing that differently sulfonated resins could be prepared. The behavior of atenolol (ATL) loading and in vitro release in the USP stimulated gastric and intestinal fluids of the obtained resins were evaluated. The drug loaded in the resin increased with increasing degree of sulfonation and hence the drug binding site in resin employed. The drug release was lower from the resins with higher content of sulfonic group due to the increase in the diffusive path depth. The drug release was a little lower in stimulated gastric fluid (SGF) than in stimulated intestinal fluids (SIF). The basic groups, ionized to a little greater extent in SGF and preferred binding with the resin rather than releasing. Hence, the differently sulfonated resins could be utilized as novel carriers for drug delivery.展开更多
A series of new chelating resins with incorporating heterocyclic functional groups: pyridine, thiadizole, benzothizole into macroporous chloromethylated polystyrene were synthesized via hydrophilic spacer arm of poly...A series of new chelating resins with incorporating heterocyclic functional groups: pyridine, thiadizole, benzothizole into macroporous chloromethylated polystyrene were synthesized via hydrophilic spacer arm of polyethylene glycol containing sulfur. These chelating resins were found to show high adsorption capacities for Ag^+, Hg^2+, Au^3+ and Pd^2+, and the presence of spacer arm can enhance adsorption ability due to increase the hydrophilicity of the chelating resins.展开更多
The recovery of rhenium from waste acid is an urgent issue due to low rhenium concentration and high sulfuric acidity.To solve the problem,novel coated solvent-impregnated resins consisting of inert resins LS-300,Alam...The recovery of rhenium from waste acid is an urgent issue due to low rhenium concentration and high sulfuric acidity.To solve the problem,novel coated solvent-impregnated resins consisting of inert resins LS-300,Alamine 304-1 and the PVA film(304-CSIRs)were prepared for the separation of Re(Ⅶ)from high sulfuric acid solutions.It was shown that the PVA film coated completely on the surfaces of LS-300 resins with a thickness of 5μm,and Alamine 304-1 distributed completely inside the porous of LS-300 resins.The adsorption fitted well with Langmuir model and pseudo-second-order model with the saturation adsorption capacity of139.40 mg·g-1.The maximum separation factor of Re(Ⅶ)versus Cu(Ⅱ)was up to 483,and 304-CSIRs had no adsorptions for As(V).The adsorption capacity of Re(Ⅶ)onto 304-CSIRs maintained in 97.79%at the fifth adsorption-desorption cycle.99.87%of rhenium was recovered by 304-CSIRs from waste acid generated from a copper smelter.展开更多
Four magnetic anion exchange resins (MAERs) were used as adsorbents to purify drinking water. The effect of water quality (pH, temperature, ionic strength, etc.) on the performance of MAER for the removal of disso...Four magnetic anion exchange resins (MAERs) were used as adsorbents to purify drinking water. The effect of water quality (pH, temperature, ionic strength, etc.) on the performance of MAER for the removal of dissolved organic matter (DOM) was also investigated. Among the four studied MAERs, the strong base resin named NDMP- 1 with high water content and enhanced exchange capacity exhibited the highest removal rate of dissolved organic carbon (DOC) (48.9% removal rate) and UV-absorbing substances (82.4% removal rate) with a resin dose of 10 mL/L after 30 rain of contact time. The MAERs could also effectively remove inorganic matter such as sulfate, nitrate and fluoride. Because of the higher specific UV absorbance (SUVA) value, the DOM in the raw water was found to be removed more effectively than that in the clarified water by NDMP resin. The temperature showed a weak influence on the removal of DOC from 6 to 26℃, while a relatively strong one at 36℃. The removal of DOM by NDMP was also affected to some extent by the pH value. Moreover, increasing the sulfate concentration in the raw water could decrease the removal rates of DOC and UV-absorbing substances.展开更多
Glass fibres/epoxy resins composites have been performed as ideal materials to make support instruments for high-energy and nuclear physics experiments. The effects of the 3,-ray irradiation on the fatigue strength, t...Glass fibres/epoxy resins composites have been performed as ideal materials to make support instruments for high-energy and nuclear physics experiments. The effects of the 3,-ray irradiation on the fatigue strength, thermal conductivities and thermal stabilities of the glass fibres/epoxy resins composites were investigated. And a two-parameter fatigue life model was established to predict the fatigue life of the composites. Results revealed that the y-ray irradiation could probably result in the degradation of epoxy resins, but hardly damage to the glass fibres. And the γ-ray irradiation treatment could significantly affect the fatigue strength of the composites at a low-cycle fatigue stage, but seldom influence at a high-cycle fatigue stage. Furthermore, the fabricated glass fibres/epoxy resins composites after the γ-ray irradiation still presented excellent fatigue strength, ideal thermal conductivities, remarkable dimensional and thermal stabilities, which can meet the actual requirements of normal operation for supporting instruments under high-energy and nuclear physics experiments.展开更多
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financially supported by the Key Laboratory of Specially Functional Polymeric Materials and Related Technology of Ministry of Education, East China University of Science & Technology, and the Fundamental Research Funds for the Central Universities (Nos. 50321041918013 and 50321041917001)。
文摘Silicon-containing arylacetylene (PSA) resins have broad application prospects because of their excellent heat resistance.However,improving their mechanical properties and interfacial bonding with reinforcement fibers while maintaining heat resistance is a challenge in engineering applications.Here,poly(diethynylbenzene-methylsilyl-3-benzonitrile)(DEB-CN) and poly(diethynylbenzene-methylsilyl-3,6-diethynylcarbazole-3-benzonitrile)(DEC-CN) were synthesized via an isopropylmagnesium chloride lithium-chloride complex (i-PrMgCl·LiCl),overcoming the compatibility problem between cyano groups and Grignard reagents.The cyano and alkyne groups in the resin underwent cyclization to form pyridine,catalyzed by the-NH-moiety in DEC-CN,resulting in extremely high thermal stability (5%weight loss temperature:669.3°C,glass transition temperature>650°C).The combination of cyano dipole-dipole pairing and hydrogen bonding greatly enhanced the resin-fiber interface properties,while the generated pyridine promoted stress relief in the crosslinked network,substantially improving the mechanical properties of the cyano-silicon-containing arylacetylene resin composites.The flexural strength of quartz fiber cloth/DEC-CN composites was 298.2 MPa at room temperature and 145.9 MPa at 500°C,corresponding to 84.0%and 127.6%enhancements,respectively,over the cyano-free counterpart.These cyano-silicon-containing arylacetylene resins exhibited a dual reinforcement mechanism involving physical interfacial interactions and chemical crosslinking,achieving a good balance between thermal stability and mechanical properties.
基金funded by the Bioeconomy grant at the Latvian State Institute of Wood Chemistry“Transition to Greener Analytical Chemistry for the Analysis of Biorefinery ProductsWith Liquid Chromatography”(No.03-24).
文摘Fast pyrolysis of pre-treated birch wood in a super-heated steam environment produces a condensate rich in anhydrosugars.With the objective to obtain several product streams from this condensate,the possibility of extracting additional chemical species is explored,thus promoting the development of a pyrolysis-based biorefinery.In this work,the extraction and recovery of pyrolytic phenols from birch wood pyrolysis condensate was studied using ion exchange resins.With an aim to achieve effective phenol recovery,while obtaining high purity levoglucosan,basic ion exchange resins,both in OH−and Cl^(−)form,as well as polystyrene-divinyl resins without functional groups were compared.This study characterizes the influence of sorbent matrix type and porosity,functional group and counter ion on the sorption of various aromatic compounds.It was concluded that the counter ion of the ion exchange resins had the most influence on the pyrolytic phenol adsorption,while in the case of unfunctionalized resins smaller pore size improved removal of phenols from the pyrolysis liquids.Of the resins tested,the most effective at the removal and recovery of pyrolytic phenols were strongly basic,macroporous,anion exchange resins in OH^(−)form.The possibility to reuse the sorbents and solvents is explored to make the over-all process more environmentally friendly and economically feasible.
文摘Bisphenol A (BPA) is the primary chemical used in the production of epoxy resins but as of today is not widely available in a bio-based form. BPA is also classified as a substance of very high concern due to its reproductive toxicity and endocrine-disrupting effects. Phlorotannins, a type of polyphenols, offer a promising structural alternative to bisphenol A as a more sustainable option. They are found in high quantities in brown algae, which are already harvested for alginate production. As a result, phlorotannins present an under-researched yet promising marine resource for the chemical industry, particularly in the area of epoxy resin formulation. In this study, a model epoxy resin compound based on phloroglucinol, the simplest phlorotannin, was chosen to explore its reactivity and the thermo-mechanical properties of epoxy resins based thereof. As hardeners well-established systems like isophorone diamine for ambient temperature cure as well as heat-curing anhydrides and dicyandiamide were used. Across all cases, thermosets with glass transition temperatures above 100?C were achieved under cross-linking conditions similar to those used today. One phthalic anhydride derivative yielded a glass transition temperature of 198?C, highlighting the significant potential of these algae-based epoxy resins for industrial uses, such as impregnating resins for fiber-reinforced plastics.
文摘Mango seed and palm oils were modified by alcoholysis and esterification process, to form alkyd resin, which is generally used in surface coatings and adhesives. N-hexane was used to extract the mango seed oil, while, palm oil was manually isolated by pressing method after heating to softness. Some physio-chemical properties, like, percentage yield, saponification value, acid value, iodine value, refractive index, etc., were carried out according to standards to determine the suitability of the oils in bio-resin synthesis. The colour intensity of the alkyd resins were tested using Gardner scale, elasticity by viscometer, hardness, chemical resistance, and other properties of the alkyd resin were tested according to standard. The Infra-Red (IR) spectra of the raw oils and their respective alkyd resins were determined before modification. Palm oil alkyd resin exhibited a characteristic straight chain of ester functional group at 1738.64 cm−1 and aromatic (C=C) ring of ester at 1730.09 cm−1 while, mango seed oil alkyd resin showed spectrum of strong peaks at 11698 cm−1 with stretching frequency to 1240 cm−1, 1221 cm−1, 1188 cm−1, indicating the presence of a carbon atom single bonded to oxygen. The hardness, glossy tests, drying time, chemical resistance, etc., of the sample alkyd resins compared well to the commercial grade alkyd resin.
文摘A new kind of modified thermoset resins were synthesized by phase-transfer Williamson reaction from novolac resin and mixtures of allyl- and propargyl-chlorides. The compositions of the resins were defined by 1H NMR (nuclear magnetic resonanse) spectroscopy and the dependence of the cured materials properties on the composition was established. Increase of a propargyl content resulted in char yield raise and the maximum value had been found for propargylated resin--58%. DSC (differential scanning calorimetry)-analysis of the resins has demonstrated that exothermic enthalpy of the curing process could be adjusted by varying the content of propargyl and allyl groups in the resin.
文摘In the present study we prepared macroporous polyvinyl alcohol beads. A series of bilirubin adsorbents were generated by immobilization of eight amine agents to the beads as ligands. The adsorption of bilirubin was evaluated by in vitro static and dynamic adsorption tests. The results show that these adsorbents have excellent adsorption efficiency and capacity. Among the eight ligands, trimethylamine (TMA), triethylamine (TEA) and 1,6- hexanediamine (HDA) showed the highest adsorption capacity. The adsorption equilibrium can be achieved in half an hour, and the adsorption percentage of bilirubin was up to 80%. Static electricity and hydrophobie interaction played the main role in bilirubin adsorption, and the adsorption was found to match the monolayer model. The excellent adsorption of these adsorbents indicates their potential in clinical treatment.
文摘By means of the synthetic approach of non-polar or weak polar oil-sorbed polymers,the gel sorption resin(GSR) and the multiporous sorption resin(MSR) were prepared.The structure of the resins,sorption power,sorption speed,desorption,and sorption of organic compounds from sewage,exhaust gas and soil were discussed.Moreover,the resins were used to decrease LOD and BOD5 values of water waste from sewage factory.Theyare a klndof potential materials for environmental control.
基金Project supported by the Natural Science Foundation of Shandong (Z2004D05) the Research and Development Project Fund of Qingdao (05-2-NS-21)
文摘Resins of complexes made from agarose-Ce4+ (RCA-Ce) and chitosan-Ce4+ (RCC-Ce) were prepared. Hydrolysis rates of methamidophos, omethoate and chlorpyrifos treated by RCA-Ce were 32.39%, 27. 12% and 46.62%, respectively, those of chlorpyrifos and methamidophos in mung bean sprout juice 38.28% and 35.45% , and that of chlorpyrifos in tea extract 59.76% . Hydrolysis rates of protein in tea extract treated by RCA-Ce increased by 86.46% . RCC-Ce could be employed in the apple juice production. The contents of methamidophos and parathion-methyl in the juice treated by RCC-Ce decreased 58.76% and 71.92% . Furthermore, RCC-Ce was used to clarification for beer by the ways of a column. RCC-Ce could hydrolyze sensitive protein and increase contents of free amino acid in the beer. Therefore, the beer treated by RCC-Ce could stay oxidation and aging procedure due to some metal ions being absorbed by RCC-Ce.
文摘With the urgent shortage of forest resource in China, using agro-residues as raw materials of composite become increasingly important. Agro-residue is the most potential fiber resource, which is helpful to sustainable development of composite industries in China. Based on a great deal of researches, this paper summarized and discussed some problems in using agro-residues as raw materials of composites, including raw material preparation, hot-pressing, bonding technology, preventing composite from going moldy. It is proposed that to manufacture the composite of rice straws or wheat straws, the isocayante resin is a suitable adhesive, and the appropriate technologies, bonding, and treatment measures are also needed.
文摘Aim To prepare the prolonged-released microspheres of mefformin hydrochloride. Methods Ion-exchange resin-drug mefformin hydrochloride complexes were prepared as core materials, and followed by coating using ethylcellulose (EC) by the emulsion solvent diffusion technique. The release rate of mefformin from the microcapsules was highly dependent on the encapsulating formulation, thus being used as an index for formulation screening. Orthogonal experiments were performed to optimize the coating formulation. Results The final chosen formulation for coating of mefformin microcapsules were as follows: ( 1 ) the ratio of EC (20cps) to EC (45cps) was 50:50; (2) the ratio of plasticizer to coating materials was 20% ;and (3) the ratio of resin-mefformin complexes to coating materials was 5 : 1. Conclusion The prolonged release microspheres of mefformin hydrochloride were successfully prepared.
基金provided by Conselho Nacional de Desenvolvimento Científico e Tecnológico(CNPq,grant 130978/2020-5)to the Fundação de AmparoàPesquisa do Estado de São Paulo(FAPESP,grant 2019/11866-5)to CAPES for the financial support.
文摘This study assessed the adsorption process and the reaction kinetics involved in the selective recovery of vanadium from an acid solution containing iron as an impurity.Four commercial resins were studied:Lewatit^(®)MonoPlus TP 209 XL,Lewatit^(®) TP 207,Dowex^(TM)M4195(chelating resin)and Lewatit^(®) MonoPlus S 200 H(strong cationic exchange resin).To investigate the effect of time on the adsorption process,batch experiments were carried out using the following initial conditions:pH 2.0,298 K,and a proportion of 1 g of resin to 50 mL of solution.The variation of pH over time was analyzed.Chelating resin released less H+ions as the adsorption occurred,resulting in a lower drop of pH when compared to S 200 H resin.Ion adsorption by the resins was also evaluated through FT-IR and SEM−EDS before and after the experiments.Among the evaluated kinetic models(pseudo-first order,pseudo-second order,Elovich and intraparticle diffusion models),the pseudo-second order model best fits the experimental data of the adsorption of vanadium and iron by all of the four resins.M4195 resin showed the highest recovery of vanadium and the lowest adsorption of iron.Kinetic data,which are fundamental to industrial processes applications,are provided.
基金financially supported by the National Natural Science Foundation of China(Nos.51974026 and 21301104)the National Key R&D Program of China(No.2018YFC1900604)the Fundamental Research Funds for the Central Universities(No.FRF-TP-16019A3)。
文摘A solid-phase extraction resin SIRs-P227/XAD-7 HP was prepared by impregnating extractant P227 onto macroporous resin XAD-7 HP beads. SIRs-P227/XAD-7 HP beads were characterized by Fourier transform infrared spectroscopy(FTIR) and scanning electron microscopy(SEM) equipped with energy-dispersive spectroscopy(EDS). The adsorption kinetics, particle size effect,adsorption isotherm, pH_(equilibrium)–lg D relationship(where D is distribution coefficient), desorption, adsorption selectivity for heavy rare earths, and impurity ions were studied. The results showed that the adsorption kinetics of Lu(III) on the SIRs-P227/XAD-7 HP beads fitted the Morris–Weber model best. The adsorbance decreased as the particle size increased. The pH_(equilibrium)–lg D relationship fitted well with a straight line, and the slope was 1.56. The experimental data fitted well with Langmuir adsorption.The calculated maximum adsorption capacity was23.8 mg·g^(-1), while the experimental datum was22.7 mg·g^(-1) at the given conditions. The adsorbed Lu(III)can be easily stripped by 0.1 mol·L^(-1) HCl. The adsorption selectivity of SIRs-P227/XAD-7 HP for heavy REs exhibited the following order: Lu>Yb>Tm>Er>Ho. The adjacent heavy rare earth(RE) separation factors β_(Lu/Yb),β_(Yb/Tm), β_(Tm/Er), and β_(Er/Ho)were 1.57, 3.00, 3.03, and 2.23,respectively, at liquid/solid ratio(L/S) equal to 3:20. The adsorption selectivity for impurity ions exhibited the followingorder:Fe >Lu>Tm>Zn>Mg>Ca>Ho>Co>Ni>Cu>Al.
基金The University Grants Commission,New Delhi for its funding of this workIndian Institute of Science,Bangalore for its instrumental support+2 种基金Department of Physics,Sri Venkateswara University,Tirupathi,for its assistance in the SEM studyUGC,New Delhi for its support under SAPDST,New Delhi for its support under FIST
文摘2-Acryloxyacetophenone (AAP) was prepared and subjected to suspension polymerization with methyl methacrylate (MMA) using azobisisobutyronitrile (AIBN) as free radical initiator. The differently sulfonated AAP-MMA cross-linked copolymer cationic exchange resins were prepared by sulfonation with concentrated sulphuric acid at 70 ~C. Several characteristics of the prepared resins were evaluated, i.e. FTIR, the ion-exchange capacity (IEC), thermo gravimetric analysis (TGA), particle size distribution and microscopic morphology. The resin characteristics were altered with degree of sulfonation, providing that differently sulfonated resins could be prepared. The behavior of atenolol (ATL) loading and in vitro release in the USP stimulated gastric and intestinal fluids of the obtained resins were evaluated. The drug loaded in the resin increased with increasing degree of sulfonation and hence the drug binding site in resin employed. The drug release was lower from the resins with higher content of sulfonic group due to the increase in the diffusive path depth. The drug release was a little lower in stimulated gastric fluid (SGF) than in stimulated intestinal fluids (SIF). The basic groups, ionized to a little greater extent in SGF and preferred binding with the resin rather than releasing. Hence, the differently sulfonated resins could be utilized as novel carriers for drug delivery.
基金The authors are grateful to the financial support by the Postdoctoral Science Foundation of China(No.2003034330)the Science Foundation for mid-youth elite of Shangdong Province+1 种基金the Natural Science Foundation of Shangdong Province(No.Q99B15)the National Natural Science Foundation of China(No.2906008)
文摘A series of new chelating resins with incorporating heterocyclic functional groups: pyridine, thiadizole, benzothizole into macroporous chloromethylated polystyrene were synthesized via hydrophilic spacer arm of polyethylene glycol containing sulfur. These chelating resins were found to show high adsorption capacities for Ag^+, Hg^2+, Au^3+ and Pd^2+, and the presence of spacer arm can enhance adsorption ability due to increase the hydrophilicity of the chelating resins.
基金financially supported by the Fundamental Research Funds for the Central Universities of Central South University(No.2019zzts243)the National Natural Science Foundation of China(No.51604303)Hunan Natural Science Fund for Distinguished Young Scholar(No.2019JJ20031)。
文摘The recovery of rhenium from waste acid is an urgent issue due to low rhenium concentration and high sulfuric acidity.To solve the problem,novel coated solvent-impregnated resins consisting of inert resins LS-300,Alamine 304-1 and the PVA film(304-CSIRs)were prepared for the separation of Re(Ⅶ)from high sulfuric acid solutions.It was shown that the PVA film coated completely on the surfaces of LS-300 resins with a thickness of 5μm,and Alamine 304-1 distributed completely inside the porous of LS-300 resins.The adsorption fitted well with Langmuir model and pseudo-second-order model with the saturation adsorption capacity of139.40 mg·g-1.The maximum separation factor of Re(Ⅶ)versus Cu(Ⅱ)was up to 483,and 304-CSIRs had no adsorptions for As(V).The adsorption capacity of Re(Ⅶ)onto 304-CSIRs maintained in 97.79%at the fifth adsorption-desorption cycle.99.87%of rhenium was recovered by 304-CSIRs from waste acid generated from a copper smelter.
基金supported by the National Natural Science Foundation of China (No.50938004)the National Science Funds for Young Scientists (No.51008152)the Jiangsu Nature Science Fund for Distinguished Scientists, China(No.BK2010006)
文摘Four magnetic anion exchange resins (MAERs) were used as adsorbents to purify drinking water. The effect of water quality (pH, temperature, ionic strength, etc.) on the performance of MAER for the removal of dissolved organic matter (DOM) was also investigated. Among the four studied MAERs, the strong base resin named NDMP- 1 with high water content and enhanced exchange capacity exhibited the highest removal rate of dissolved organic carbon (DOC) (48.9% removal rate) and UV-absorbing substances (82.4% removal rate) with a resin dose of 10 mL/L after 30 rain of contact time. The MAERs could also effectively remove inorganic matter such as sulfate, nitrate and fluoride. Because of the higher specific UV absorbance (SUVA) value, the DOM in the raw water was found to be removed more effectively than that in the clarified water by NDMP resin. The temperature showed a weak influence on the removal of DOC from 6 to 26℃, while a relatively strong one at 36℃. The removal of DOM by NDMP was also affected to some extent by the pH value. Moreover, increasing the sulfate concentration in the raw water could decrease the removal rates of DOC and UV-absorbing substances.
基金financially supported by the National Natural Science Foundation of China (No. 51605025)the Major Program of National Key Research and Development Program of China (2016YFC0802905)+2 种基金the Fundamental Research Funds for the Central Universities (FRF-GF-17-B19)the BEPC great reconstruction projectthe Knowledge Innovation Fund of the Chinese Academy of Sciences, U-603 and U-34 (IHEP)
文摘Glass fibres/epoxy resins composites have been performed as ideal materials to make support instruments for high-energy and nuclear physics experiments. The effects of the 3,-ray irradiation on the fatigue strength, thermal conductivities and thermal stabilities of the glass fibres/epoxy resins composites were investigated. And a two-parameter fatigue life model was established to predict the fatigue life of the composites. Results revealed that the y-ray irradiation could probably result in the degradation of epoxy resins, but hardly damage to the glass fibres. And the γ-ray irradiation treatment could significantly affect the fatigue strength of the composites at a low-cycle fatigue stage, but seldom influence at a high-cycle fatigue stage. Furthermore, the fabricated glass fibres/epoxy resins composites after the γ-ray irradiation still presented excellent fatigue strength, ideal thermal conductivities, remarkable dimensional and thermal stabilities, which can meet the actual requirements of normal operation for supporting instruments under high-energy and nuclear physics experiments.