Studies have shown that chitosan protects against neurodegenerative diseases. However, the precise mechanism remains poorly understood. In this study, we administered chitosan intragastrically to an MPTP-induced mouse...Studies have shown that chitosan protects against neurodegenerative diseases. However, the precise mechanism remains poorly understood. In this study, we administered chitosan intragastrically to an MPTP-induced mouse model of Parkinson's disease and found that it effectively reduced dopamine neuron injury, neurotransmitter dopamine release, and motor symptoms. These neuroprotective effects of chitosan were related to bacterial metabolites, specifically shortchain fatty acids, and chitosan administration altered intestinal microbial diversity and decreased short-chain fatty acid production in the gut. Furthermore, chitosan effectively reduced damage to the intestinal barrier and the blood–brain barrier. Finally, we demonstrated that chitosan improved intestinal barrier function and alleviated inflammation in both the peripheral nervous system and the central nervous system by reducing acetate levels. Based on these findings, we suggest a molecular mechanism by which chitosan decreases inflammation through reducing acetate levels and repairing the intestinal and blood–brain barriers, thereby alleviating symptoms of Parkinson's disease.展开更多
This study delves into the optimization of the methanol-vinyl acetate(VAC)azeotrope separation process via pressure swing distillation(PSD),along with an evaluation of its energy-saving potential.The methanol-VAC syst...This study delves into the optimization of the methanol-vinyl acetate(VAC)azeotrope separation process via pressure swing distillation(PSD),along with an evaluation of its energy-saving potential.The methanol-VAC system,a polar azeotro pe highly susceptible to pressure variations,presents notable separation complexities in polyvinyl alcohol production.Aspen Plus simulations were utilized to assess the feasibility of PSD,with particular emphasis on critical process parameters such as the number of theoretical plates,feed position,reflux ratio,and sidestream extraction location.The results indicate that PSD demonstrates remarkable efficacy in separating methanol and VAC,achieving purities of 99.88%and 99.73%respectively.When compared to extractive distillation,PSD achieves a reduction of 9.07 t·h^(-1)in steam consumption and minimizes wastewater generation by 20.77 t·h^(-1).Furthermore,the economic assessment reveals a 7.91%decrease in the total annual cost associated with PSD.This study not only provides theoretical insights but also offers practical guidance for the design of energyefficient and sustainable separation processes.Future research will focus on extending the analysis to encompass multi-pressure scenarios,further enhancing the applicability and robustness of the findings.展开更多
Design and control of pressure-swing distillation(PSD) with different heat integration modes for the separation of methyl acetate/methanol azeotrope are explored using Aspen Plus and Aspen Dynamics. First, an optimum ...Design and control of pressure-swing distillation(PSD) with different heat integration modes for the separation of methyl acetate/methanol azeotrope are explored using Aspen Plus and Aspen Dynamics. First, an optimum steady-state separation configuration conditions are obtained via taking the total annual cost(TAC) or total reboiler heat duty as the objective functions. The results show that about 27.68% and 25.40% saving in TAC can be achieved by the PSD with full and partial heat integration compared to PSD without heat integration. Second,temperature control tray locations are obtained according to the sensitivity criterion and singular value decomposition(SVD) analysis and the single-end control structure is effective based on the feed composition sensitivity analysis. Finally, the comparison of dynamic controllability is made among various control structures for PSD with partial and full heat integration. It is shown that both control structures of composition/temperature cascade and pressure-compensated temperature have a good dynamic response performance for PSD with heat integration facing feed flowrate and composition disturbances. However, PSD with full heat integration performs the poor controllability despite of a little bit of economy.展开更多
In order to separate methyl acetate and methanol azeotrope, the ionic liquid(IL) 1,3-dimethylimidazolium dimethylphosphate([DMIM]DMP) was used as the solvent. The Aspen Plus software was used to design and optimize th...In order to separate methyl acetate and methanol azeotrope, the ionic liquid(IL) 1,3-dimethylimidazolium dimethylphosphate([DMIM]DMP) was used as the solvent. The Aspen Plus software was used to design and optimize the extractive distillation process. Under the optimized conditions, the mass fractions of methyl acetate and methanol were both above 99.5%. Compared with the dimethyl sulfoxide(DMSO) process, the [DMIM]DMP process has the advantages of saving energy and lower equipment investment cost. The result shows that using [DMIM]DMP as the solvent to separate a methyl acetate and methanol azeotrope has better prospect in industrial application.展开更多
Developing favorable bio-based polymers that replace petroleum-based plastics is an essential environmental demand.Lignin is a by-product of the chemical pulping industry.It is a natural UV protection ingredient in br...Developing favorable bio-based polymers that replace petroleum-based plastics is an essential environmental demand.Lignin is a by-product of the chemical pulping industry.It is a natural UV protection ingredient in broad-spectrum(UVA and UVB)sunscreens.It could be partially and selectively acetylated in a simple,fast,and more reliable process.In this work,a composite film was prepared with UV-resistant properties through a casting method.Bio-based cellulose acetate(CA)was employed as a major matrix while nano-acetylated kraft lignin(AL-NPs)was used as filler during synthesizing UV-shielding films loaded with various amounts(1–5 wt.%)of AL-NPs.Kraft lignin was acetylated through a simple and fast microwave-assisted process using acetic acid as a solvent and acetylating agent.The physicochemical and morphological characteristics of the prepared films were evaluated using different methods,including scanning electron microscopy(SEM),Fourier Transform Infrared Spectroscopy(FTIR),X-ray diffraction analysis(XRD),mechanical testing and contact angle measurement.The UV-Vis spectroscopy optical investigation of the prepared films revealed that AL-NPs in the CA matrix showed strong UV absorption.This feature demonstrated the effectiveness of our research in developing UV-resistant bio-based polymer films.Hence,the prepared films can be considered as successful candidates to be applied in packaging applications.展开更多
The vapor-liquid equilibrium of binary mixtures of propyl acetate, butyl acetate and isobutyl acetate with meth- anol has been determined at a constant pressure of 0.6 MPa. Results have been modeled with the Peng-Robi...The vapor-liquid equilibrium of binary mixtures of propyl acetate, butyl acetate and isobutyl acetate with meth- anol has been determined at a constant pressure of 0.6 MPa. Results have been modeled with the Peng-Robinson equation, a traditional cubic equation of state widely employed in chemical industries, as well as with the perturbed-chain statistical associating fluid PC-SAFT theory of Gross-Sadowski. By correlation of the binary inter- action parameters of these equations, the measured vapor-liquid equilibrium data can be accurately predicted. Thus, this work shows that these models are able to represent the experimental data for systems with associating comoounds via hydrogen bonding.展开更多
A new gold self-relay catalytic annulation/nucleophilic substitution cascade of 1,3-enyne acetates with cyclic ether acetals is reported,enabling highly diastereoselective access to cyclic etherified cyclopentenones w...A new gold self-relay catalytic annulation/nucleophilic substitution cascade of 1,3-enyne acetates with cyclic ether acetals is reported,enabling highly diastereoselective access to cyclic etherified cyclopentenones with cyclic quaternary centers in moderate to good yields and>19∶1 dr.This catalysis enables the direct construction of two types of carboncyclic skeletons by adjusting the olefin types of 1,3-enyne acetates.When 1,3-enyne acetates bearing a cyclic alkene unit were used,5~6 fused bicarbocyclic products were diastereoselectively synthesized,whereas the reaction of acyclic 1,3-enyne acetates resulted in five-memebered carbocyclic framework.Notably,cyclic ether acetals are commonly used as protecting groups in traditional multistep organic syntheses,and in this reaction,such reagents serve as electrophilic cyclic ether precursors,achieving new uses for old reagents.The current method demonstrates good functional group compatibility,a broad substrate scope and high diastereoselectivity,providing a new synthetic strategy toward functionalized cyclopentenones.展开更多
Background: The present study covered an assessment of methanolic acetate fractions of Pistia stratiotes, commonly known as water lettuce, for analgesic, anti-inflammatory, and CNS depressant activities.Methods: The m...Background: The present study covered an assessment of methanolic acetate fractions of Pistia stratiotes, commonly known as water lettuce, for analgesic, anti-inflammatory, and CNS depressant activities.Methods: The methanol acetate fractions were extracted from Pistia stratiotes and administered to the experimental animals as 200 and 400 mg/kg doses to determine the effect on acetic acid-induced writhing and formalin-induced licking and biting,for the assessment of analgesic activity. The anti-inflammatory assay was done using the carrageenan-induced hind paw edema method, while assessment of CNS depressant activity was done using the open field and hole cross tests. The effects were compared to standard reference drugs.Results: At both doses(200 and 400 mg/kg body weight), the methanolic acetate extract of P. stratiotes showed significant analgesic action(P < 0.05) against acetic acid-induced writhing. The extract was also found to give significant protection against licking and biting at both doses. The methanolic acetate extract of P. stratiotes showed a significant(P < 0.05) anti-inflammatory effect from 0 minutes up to 3 hours in the carrageenan-induced paw edema test. In the CNS depressant assay,the methanolic acetate extract showed significant(P < 0.05) depressant activity at both doses from 30 to 120 minutes in both the hole cross and open field tests.Conclusion: Thus we can conclude that P. stratiotes extracts have significant analgesic, anti-inflammatory, and CNS depressant activity, compared to standard compounds, in an animal model.展开更多
The neurotransmitter 5-hydroxytryptamine(5-HT),primarily produced by intestinal enterochromaffin(EC)cells,relies on tryptophan hydroxylase 1(TPH1)for synthesis.Research suggested Bifidobacterium breve CCFM1025’s pote...The neurotransmitter 5-hydroxytryptamine(5-HT),primarily produced by intestinal enterochromaffin(EC)cells,relies on tryptophan hydroxylase 1(TPH1)for synthesis.Research suggested Bifidobacterium breve CCFM1025’s potential in regulating Tph1 gene expression,maintaining 5-HT levels in stressed mice,but its precise mechanisms were unclear.This study used metabolomic techniques to assess probiotic fermentation products,revealing acetate as the crucial element in Bb-CCFM1025’s regulation of gut 5-HT synthesis.Further exploration correlated acetate with Tph1 transcription in intestinal organoids.Transcriptomic methods and quantitative reverse transcription polymerase chain reaction validation demonstrated how acetate facilitated 5-HT synthesis and secretion.It unveiled that acetate orchestrates signaling pathways(phosphoinositide 3-kinase-protein kinase B(PI3K-AKT),phospholipase C-phosphorylated extracellular signal-regulated kinase(PLC-pERK),and PLC-1,4,5-trisphosphate(IP3)-Ca^(2+))within EC,enabling 5-HT production.These findings elucidate the biochemical mechanisms behind specific probiotics’effects,aiding in the targeted selection of similar beneficial strains.This study offers theoretical support for choosing probiotics with analogous functionalities based on their physiological impacts.展开更多
Mo_(2)CT_(x)MXene is a novel two-dimensional material,which is generally made by the etching of inorganic acid solutions,such as hydrofluoric acid(HF)or hydrochloric acid(HCl).Those solutions are always corrosive and ...Mo_(2)CT_(x)MXene is a novel two-dimensional material,which is generally made by the etching of inorganic acid solutions,such as hydrofluoric acid(HF)or hydrochloric acid(HCl).Those solutions are always corrosive and hazardous.In this paper,a mild organic acid,acetic acid(CH_(3)COOH),was selected to synthesize Mo_(2)CT_(x)MXene.30 mL acetic acid(HAc)with the concentration of 13 mol/L was mixed with 2 g acetate(CH_(3)COONa or CH_(3)COOK)and 10 mL water to make etching solution(NaAc+HAc or KAc+HAc).In the solution,the concentration of CH_(3)COO^(-)was 10 mol/L,the concentration of Na^(+)/K^(+)is 0.6/0.5 mol/L.The pH value is 2.8.Mo_(2)CT_(x)was obtained by hydrothermal etching at 240℃for 1 d.Compared with the general method of HF etching,the etchant is milder and the etching process is safer.On the surface of Mo_(2)CT_(x)nanosheet made by this method,acetate group(CH_(3)COO^(-))was adsorbed as termination,which is larger than the F/O/OH termination of that made by general HF etching.The lattice parameter c(LP c)of Mo_(2)CT_(x)etched with NaAc+HAc/KAc+HAc is 21.09Å/20.89Å.Moreover,the specific surface areas of the samples etched by NaAc+HAc and KAc+HAc were 18.1 m^(2)/g and 14.1 m^(2)/g,respectively,which were much larger than those etched by conventional methods.As the anode of lithium-ion battery,the specific capacity under current density of 100 mA/g at 100 th cycle was 108 mA·h/g,which is higher than the capacity of samples made by general HF etching.This work reports a novel method to make Mo_(2)CT_(x)MXene by the solution of mild acetic acid.The samples made by this method had very high specific surface area and relatively high lithium-storage performance.展开更多
Chalcopyrite is often intergrown with talc,which,after grinding,forms ultrafine particles(<10μm)that readily coat chalcopyrite surfaces,hindering flotation and causing significant losses in tailings.This study eva...Chalcopyrite is often intergrown with talc,which,after grinding,forms ultrafine particles(<10μm)that readily coat chalcopyrite surfaces,hindering flotation and causing significant losses in tailings.This study evaluates polyvinyl acetate(PVAc),a thermoplastic polymer,as a selective flocculant to enhance reverse flot ation separation of chalcopyrite from ultrafine talc.Flotation tests showed that at a PVAc dosage of 40 mg/L,talc can be effectively and selectively removed,enabling efficient separation.Laser particle size analysis and scanning electron microscopy-energy dispersive spectrometry(SEM-EDS)confirmed that PVAc promotes selective talc aggregation without affecting chalcopyrite.X-ray photoelectron spectroscopy(XPS)and density functional theory(DFT)calculations revealed that hydrogen bonding between PVAc ester groups and surface hydroxyls on talc drives the flocculation,while chalcopyrite lacks suitable binding sites.PVAc adsorption also enhances talc hydrophobicity.Furthermore,particle-bubble coverage angle measurements and extended Derjaguin-Landau-Verwey-Overbeek(DLVO)theory theoretical calculations demonstrated that PVAc-induced flocculation increases attractive interactions between talc and bubbles,shifting the total interaction energy from repulsive to attractive and promoting bubble-particle attachment.This study clarifies the selective adsorption and flocculation mechanisms of PVAc and reveals the coupling of flocculation and flotation of ultrafine talc from a particle-bubble capture perspective,while expanding the potential of ester-based polymers for ultrafine mineral recovery.展开更多
Lead （Pb） is one of the most common environmental toxicants, exposure to which can cause significant neurotoxicity and an associated decline in brain function. This study investigated the possible neuroprotective ro...Lead （Pb） is one of the most common environmental toxicants, exposure to which can cause significant neurotoxicity and an associated decline in brain function. This study investigated the possible neuroprotective role oflndigofera oblongifolia leaf methanolic extract （IOLME） against lead-induced neurotoxicity. Rats were intraperitoneally injected with lead acetate, with or without IOLME （intragastric administration for 5 days）, and the neuroprotective effect of IOLME was assessed by measuring the lead concentration, redox status （lipid peroxidation, nitric oxide and glutathione）, enzymatic antioxidant activities （superoxide dismutase, catalase, glutathione peroxidase and reductase）, PCR assays of apoptosis markers （Bax and Bcl-2） and histopathology of the brain. The increases in the lipid peroxidation, nitric oxide, and apoptosis, the decreases in the glutathione level and the activity of antioxidant enzymes, and the altered histology of the brain induced by lead acetate were mitigated in the brain of rats pre-treated with IOLME. These findings indicate that IOLME has beneficial effects and it mitigates lead acetate-induced neurotoxicity via its antiox-idant and anti-apoptotic activities.展开更多
The production of high-purity propylene glycol monomethyl ether acetate(PMA)through the transesterification of propylene glycol monomethyl ether(PM)and methyl acetate(MeOAc)is traditionally catalyzed by sodium methoxi...The production of high-purity propylene glycol monomethyl ether acetate(PMA)through the transesterification of propylene glycol monomethyl ether(PM)and methyl acetate(MeOAc)is traditionally catalyzed by sodium methoxide.However,the practical application of this method is significantly hindered by the inherent limitations of sodium methoxide,such as its high sensitivity to moisture and propensity for solid precipitation,which impede its effective use in continuous processes.This work proposed a continuous catalytic distillation(CD)process utilizing Amberlyst 15 cation exchange resin as the catalyst.A comprehensive series of reaction kinetic and CD experiments were conducted to evaluate the performance of the proposed process.The results demonstrate that under the optimal operating conditions,namely an ester-to-ether molar ratio of 6:1,a refluxratio of 5:1,a total feed rate of 0.92 g‧min^(-1),and an evaporation rate of 266.47 m^(3)‧m^(-2)‧h^(-1),the conversion rate of PM achieves 99.95%,and the PMA yield is 97.31%.Based on these findings,a process flowsheet for a continuous CD process tailored for the production of electronic-grade PMA is presented.This design incorporates light and heavy removal steps to ensure the production of PMA with a purity of 99.99%.Additionally,the process utilizes pressure swing distillation to recover MeOAc,thereby enhancing the overall efficiencyand sustainability of the production process.The proposed continuous CD process offers a highly efficient,cost-effective,and environmentally sustainable solution for the production of electronic-grade PMA.展开更多
Dear Editor： Pergularia daemia Forsk （Asclepiadaceae） is a perennial twining herb commonly known as veliparuthi in Tamil. The plant has anthelmintic, laxative, antidiabetic, hepatoprotective and anti-inflammatory ...Dear Editor： Pergularia daemia Forsk （Asclepiadaceae） is a perennial twining herb commonly known as veliparuthi in Tamil. The plant has anthelmintic, laxative, antidiabetic, hepatoprotective and anti-inflammatory activities. The pharmacological properties of this plant come from bioactive phytochemicals such as alkaloids, triterpenes, saponins and flavonoids. Phytochemically, the plant has been investigated for the presence of cardenolides, alkaloids, saponins and steroidal compoundst. In the present study, we developed a rapid method for identification and quantitative determination of putative phyto compounds in the crude extracts of ethyl acetate and methanol from whole plant of Pergularia daemia.展开更多
The efficient production of acetate through electrochemical CO_(2)reduction reaction(eCO_(2)RR)with low energy consumption has consistently been a challenging yet extremely significant task.Current catalysts suffered ...The efficient production of acetate through electrochemical CO_(2)reduction reaction(eCO_(2)RR)with low energy consumption has consistently been a challenging yet extremely significant task.Current catalysts suffered from high energy consumption and low relative purity of acetate product.Herein,we report ultrasmall Cu_(2)O nanoparticles with an average size of 2.5±0.09 nm immobilized on a conductive copper-based metal-organic framework(Cu-THQ)(denoted as Cu_(2)O@Cu-THQ),which attained a Faradaic efficiency of 65(3)%for acetate at a very low potential of-0.3 V vs.RHE with a current density of 10.5 m A/cm^(2).Importantly,as there are no other liquid phase products such as formate,methanol or ethanol,the relative purity of the obtained acetate product was as high as 100%.Taking into account the relative purity of the liquid product,current density,and energy consumption,the performance for electroreduction of CO_(2)to acetate of Cu_(2)O@Cu-THQ is not only much higher than that of the commercial Cu_(2)O nanoparticles,but also higher than those of all reported catalysts.Operando infrared spectroscopy and theoretical calculations indicated that the synergy effect between Cu-THQ and Cu_(2)O promoted the e CO_(2)RR to yield acetate.Specifically,the hydroxyl group on the organic ligand THQ in the Cu-THQ formed hydrogen bond interactions with the key C_(2)intermediates(*CH_(2)COOH and*HOCCOH)adsorbed on Cu_(2)O,which played a crucial role in stabilizing the key C_(2)intermediates and thus reduced the formation energy of the key C_(2) intermediates.展开更多
Secondary aluminum dross(SAD)is a rich source of recyclable aluminum but poses considerable risk due to its high AlN con-tent.Therefore,thoroughly removing AlN is essential,but intricate aluminum components and expens...Secondary aluminum dross(SAD)is a rich source of recyclable aluminum but poses considerable risk due to its high AlN con-tent.Therefore,thoroughly removing AlN is essential,but intricate aluminum components and expensive additives pose challenges to the process.In this study,waste sodium acetate is proposed as an environmentally friendly additive for completely removing AlN and enhancing the extraction of aluminum from SAD.Through the exothermic decomposition of NaAc,reactions can occur at 850℃.AlN removal efficiency reached 93.19%after sintering,whereas Al leaching efficiency in the subsequent leaching process reached 90.49%,which were 37.86%and 375.26%higher than the removal efficiency of the control,respectively.These favorable results were attributed to the comprehensive transformation of aluminum species.The formation of soluble phase Na_(1.95)Al_(1.95)Si_(0.05)O_(4) occurred during the destruction of the Al_(2)O_(3) layer surrounding AlN and the transformation of other aluminum components.AlN decomposed upon contact with NaAc.There-fore,this study utilizes the decomposition properties of NaAc to provide an efficient and environmentally friendly route for removing AlN and extracting Al from SAD.展开更多
Flexible polymer-based foam sensors have significant potential for application in wearable electronics and motion monitoring.However,these prospects are hindered by the complex and unenvironmentally friendly manufactu...Flexible polymer-based foam sensors have significant potential for application in wearable electronics and motion monitoring.However,these prospects are hindered by the complex and unenvironmentally friendly manufacturing processes.In this study,we employed melt blending and supercritical carbon dioxide foaming to fabricate an ethylene-vinyl acetate copolymer(EVA)/low-density polyethylene(LDPE)/carbon nanotube(CNT)piezoresistive foam sensor.The cross-linking agent bis(tert-butyldioxyisopropyl)benzene and the conductive filler CNT were incorporated into the EVA/LDPE composite,successfully achieving a chemically cross-linked and physically entangled composite structure that significantly enhanced the storage modulus and complex viscosity.Additionally,the compressive strength of EVA/LDPE/CNT foam with 10 parts per hundred rubber(phr)CNT reached 1.37 MPa at 50%compression,marking a 340%increase compared to the 0.31 MPa of the CNT-free sample.Furthermore,the EVA/LDPE/CNT composite foams,which incorporated 10 phr CNT,were prepared under specific foaming conditions,resulting in an ultra-low density of 0.11 g/cm^(3) and a higher sensitivity,with a gauge factor of–2.3.The piezoresistive foam sensors developed in this work could accurately detect human motion,thereby expanding their applications in the field of piezoresistive foam sensors and providing an effective strategy for the advancement of high-performance piezoresistive foam sensors.展开更多
Aiming at the problems of insufficient activity and selectivity of Cu-based catalysts in CO_(2)hydrogenation to methanol,Al_(2)O_(3),ZrO_(2)and CeO_(2)modified Cu-ZnO catalysts by the co-precipitation method were prep...Aiming at the problems of insufficient activity and selectivity of Cu-based catalysts in CO_(2)hydrogenation to methanol,Al_(2)O_(3),ZrO_(2)and CeO_(2)modified Cu-ZnO catalysts by the co-precipitation method were prepared,and the influence mechanism of additives on the structure-performance relationship of the catalysts was systematically explored.Through a variety of characterization methods such as XRD,N2 physical adsorption-desorption,TEM,H_(2)-TPR,CO_(2)-TPD and XPS,combined with catalytic performance evaluation experiments,the correlation between the microstructure of catalysts and the reaction performance of CO_(2)hydrogenation to methanol was analyzed in depth.The results show that metal additives significantly improve the performance of catalysts.After the introduction of additives,the specific surface area and pore volume of the catalysts increase,the grain size of Cu decreases,and its dispersion improves.The Ce-modified CZC catalyst exhibited the best performance,with the grain size of CuO as small as 11.41 nm,and the surface oxygen vacancy concentration(OⅡ/OⅠ=3.15)was significantly higher than that of other samples.The reaction performance test shows that under the conditions of 2.8 MPa,8000 h−1 and 280℃,the CO_(2)conversion of the CZC catalyst reached 18.83%,the methanol selectivity was 68.40%,and the methanol yield was 12.88%,all of which are superior to other catalysts.Its excellent performance can be attributed to the fact that CeO_(2)enhances the metal-support interaction,increases the surface basicity,promotes the adsorption and activation of CO_(2),and simultaneously inhibits the reverse water-gas shift side reaction.This study clarifies the structure-activity regulation mechanism of additive modification on Cu-ZnO catalysts,providing a theoretical basis and technical reference for the development of efficient catalysts for CO_(2)hydrogenation to methanol.展开更多
The coupling reactions of methanol and long-chain alkanes(n-dodecane,n-tetradecane and n-hexadecane)over CHA-type molecular sieves were studied in a fixed bed reactor.Over SAPO-34 and SSZ-13,it was found that the indu...The coupling reactions of methanol and long-chain alkanes(n-dodecane,n-tetradecane and n-hexadecane)over CHA-type molecular sieves were studied in a fixed bed reactor.Over SAPO-34 and SSZ-13,it was found that the induction period of methanol conversion was shortened by the introduction of long-chain alkanes.However,the addition of long-chain alkanes had little influence on the product distribution.Polymethylbenzenes and the derivatives were the main retained species on spent SSZ-13 catalyst,while adamantanes were the main retained species on SAPO-34.This indicates that coking species formation was mainly related to the further transformation of long-chain alkane/methanol coupling products at acid sites of the molecular sieve.These findings provide valuable information of long chain alkanes conversion and methanol reaction behavior of induction period over small pore CHA molecular sieves.展开更多
基金supported by the National Natural Science Foundation of China,Nos. 32260196 (to JY), 81860646 (to ZY) and 31860274 (to JY)a grant from Yunnan Department of Science and Technology,Nos. 202101AT070251 (to JY), 202201AS070084 (to ZY), 202301AY070001-239 (to JY), 202101AZ070001-012, and 2019FI016 (to ZY)。
文摘Studies have shown that chitosan protects against neurodegenerative diseases. However, the precise mechanism remains poorly understood. In this study, we administered chitosan intragastrically to an MPTP-induced mouse model of Parkinson's disease and found that it effectively reduced dopamine neuron injury, neurotransmitter dopamine release, and motor symptoms. These neuroprotective effects of chitosan were related to bacterial metabolites, specifically shortchain fatty acids, and chitosan administration altered intestinal microbial diversity and decreased short-chain fatty acid production in the gut. Furthermore, chitosan effectively reduced damage to the intestinal barrier and the blood–brain barrier. Finally, we demonstrated that chitosan improved intestinal barrier function and alleviated inflammation in both the peripheral nervous system and the central nervous system by reducing acetate levels. Based on these findings, we suggest a molecular mechanism by which chitosan decreases inflammation through reducing acetate levels and repairing the intestinal and blood–brain barriers, thereby alleviating symptoms of Parkinson's disease.
基金financial support from the National Key Research and Development Program of China(2022YFC2106300)the National Nature Science Foundation of China(U2267226)。
文摘This study delves into the optimization of the methanol-vinyl acetate(VAC)azeotrope separation process via pressure swing distillation(PSD),along with an evaluation of its energy-saving potential.The methanol-VAC system,a polar azeotro pe highly susceptible to pressure variations,presents notable separation complexities in polyvinyl alcohol production.Aspen Plus simulations were utilized to assess the feasibility of PSD,with particular emphasis on critical process parameters such as the number of theoretical plates,feed position,reflux ratio,and sidestream extraction location.The results indicate that PSD demonstrates remarkable efficacy in separating methanol and VAC,achieving purities of 99.88%and 99.73%respectively.When compared to extractive distillation,PSD achieves a reduction of 9.07 t·h^(-1)in steam consumption and minimizes wastewater generation by 20.77 t·h^(-1).Furthermore,the economic assessment reveals a 7.91%decrease in the total annual cost associated with PSD.This study not only provides theoretical insights but also offers practical guidance for the design of energyefficient and sustainable separation processes.Future research will focus on extending the analysis to encompass multi-pressure scenarios,further enhancing the applicability and robustness of the findings.
文摘Design and control of pressure-swing distillation(PSD) with different heat integration modes for the separation of methyl acetate/methanol azeotrope are explored using Aspen Plus and Aspen Dynamics. First, an optimum steady-state separation configuration conditions are obtained via taking the total annual cost(TAC) or total reboiler heat duty as the objective functions. The results show that about 27.68% and 25.40% saving in TAC can be achieved by the PSD with full and partial heat integration compared to PSD without heat integration. Second,temperature control tray locations are obtained according to the sensitivity criterion and singular value decomposition(SVD) analysis and the single-end control structure is effective based on the feed composition sensitivity analysis. Finally, the comparison of dynamic controllability is made among various control structures for PSD with partial and full heat integration. It is shown that both control structures of composition/temperature cascade and pressure-compensated temperature have a good dynamic response performance for PSD with heat integration facing feed flowrate and composition disturbances. However, PSD with full heat integration performs the poor controllability despite of a little bit of economy.
基金financially supported by the Guizhou Province Science and Technology United Fund (Qiankehe J zi LKLS[2013]28, LKLS[2013]27)the Guizhou Province Education Department (GZSJG10977201604)+3 种基金the Excellent Engineers Education Training Plan (LPSSY zyjypyjh201702)the Guizhou Province Education Department (Qianjiaohe KY zi [2017]258)Guizhou Solid Waste Recycling Laboratory of Coal Utilization ([2011]278)the Guizhou Ordinary College Innovation Team of Coal Solid Waste Recycling Technology ([2014]46)
文摘In order to separate methyl acetate and methanol azeotrope, the ionic liquid(IL) 1,3-dimethylimidazolium dimethylphosphate([DMIM]DMP) was used as the solvent. The Aspen Plus software was used to design and optimize the extractive distillation process. Under the optimized conditions, the mass fractions of methyl acetate and methanol were both above 99.5%. Compared with the dimethyl sulfoxide(DMSO) process, the [DMIM]DMP process has the advantages of saving energy and lower equipment investment cost. The result shows that using [DMIM]DMP as the solvent to separate a methyl acetate and methanol azeotrope has better prospect in industrial application.
文摘Developing favorable bio-based polymers that replace petroleum-based plastics is an essential environmental demand.Lignin is a by-product of the chemical pulping industry.It is a natural UV protection ingredient in broad-spectrum(UVA and UVB)sunscreens.It could be partially and selectively acetylated in a simple,fast,and more reliable process.In this work,a composite film was prepared with UV-resistant properties through a casting method.Bio-based cellulose acetate(CA)was employed as a major matrix while nano-acetylated kraft lignin(AL-NPs)was used as filler during synthesizing UV-shielding films loaded with various amounts(1–5 wt.%)of AL-NPs.Kraft lignin was acetylated through a simple and fast microwave-assisted process using acetic acid as a solvent and acetylating agent.The physicochemical and morphological characteristics of the prepared films were evaluated using different methods,including scanning electron microscopy(SEM),Fourier Transform Infrared Spectroscopy(FTIR),X-ray diffraction analysis(XRD),mechanical testing and contact angle measurement.The UV-Vis spectroscopy optical investigation of the prepared films revealed that AL-NPs in the CA matrix showed strong UV absorption.This feature demonstrated the effectiveness of our research in developing UV-resistant bio-based polymer films.Hence,the prepared films can be considered as successful candidates to be applied in packaging applications.
文摘The vapor-liquid equilibrium of binary mixtures of propyl acetate, butyl acetate and isobutyl acetate with meth- anol has been determined at a constant pressure of 0.6 MPa. Results have been modeled with the Peng-Robinson equation, a traditional cubic equation of state widely employed in chemical industries, as well as with the perturbed-chain statistical associating fluid PC-SAFT theory of Gross-Sadowski. By correlation of the binary inter- action parameters of these equations, the measured vapor-liquid equilibrium data can be accurately predicted. Thus, this work shows that these models are able to represent the experimental data for systems with associating comoounds via hydrogen bonding.
文摘A new gold self-relay catalytic annulation/nucleophilic substitution cascade of 1,3-enyne acetates with cyclic ether acetals is reported,enabling highly diastereoselective access to cyclic etherified cyclopentenones with cyclic quaternary centers in moderate to good yields and>19∶1 dr.This catalysis enables the direct construction of two types of carboncyclic skeletons by adjusting the olefin types of 1,3-enyne acetates.When 1,3-enyne acetates bearing a cyclic alkene unit were used,5~6 fused bicarbocyclic products were diastereoselectively synthesized,whereas the reaction of acyclic 1,3-enyne acetates resulted in five-memebered carbocyclic framework.Notably,cyclic ether acetals are commonly used as protecting groups in traditional multistep organic syntheses,and in this reaction,such reagents serve as electrophilic cyclic ether precursors,achieving new uses for old reagents.The current method demonstrates good functional group compatibility,a broad substrate scope and high diastereoselectivity,providing a new synthetic strategy toward functionalized cyclopentenones.
文摘Background: The present study covered an assessment of methanolic acetate fractions of Pistia stratiotes, commonly known as water lettuce, for analgesic, anti-inflammatory, and CNS depressant activities.Methods: The methanol acetate fractions were extracted from Pistia stratiotes and administered to the experimental animals as 200 and 400 mg/kg doses to determine the effect on acetic acid-induced writhing and formalin-induced licking and biting,for the assessment of analgesic activity. The anti-inflammatory assay was done using the carrageenan-induced hind paw edema method, while assessment of CNS depressant activity was done using the open field and hole cross tests. The effects were compared to standard reference drugs.Results: At both doses(200 and 400 mg/kg body weight), the methanolic acetate extract of P. stratiotes showed significant analgesic action(P < 0.05) against acetic acid-induced writhing. The extract was also found to give significant protection against licking and biting at both doses. The methanolic acetate extract of P. stratiotes showed a significant(P < 0.05) anti-inflammatory effect from 0 minutes up to 3 hours in the carrageenan-induced paw edema test. In the CNS depressant assay,the methanolic acetate extract showed significant(P < 0.05) depressant activity at both doses from 30 to 120 minutes in both the hole cross and open field tests.Conclusion: Thus we can conclude that P. stratiotes extracts have significant analgesic, anti-inflammatory, and CNS depressant activity, compared to standard compounds, in an animal model.
基金supported by the National Natural Science Foundation of China(32201988)Natural Science Foundation of Jiangsu Province(BK20210456)+3 种基金Special Fund for Science and Technology Program of Jiangsu Province(BM2022019)the National Key R&D Program of China(2023YFC2506004)the Fundamental Research Funds for the Central Universities(JUSRP123047)the Program of Collaborative Innovation Centre of Food Safety and Quality Control in Jiangsu Province.
文摘The neurotransmitter 5-hydroxytryptamine(5-HT),primarily produced by intestinal enterochromaffin(EC)cells,relies on tryptophan hydroxylase 1(TPH1)for synthesis.Research suggested Bifidobacterium breve CCFM1025’s potential in regulating Tph1 gene expression,maintaining 5-HT levels in stressed mice,but its precise mechanisms were unclear.This study used metabolomic techniques to assess probiotic fermentation products,revealing acetate as the crucial element in Bb-CCFM1025’s regulation of gut 5-HT synthesis.Further exploration correlated acetate with Tph1 transcription in intestinal organoids.Transcriptomic methods and quantitative reverse transcription polymerase chain reaction validation demonstrated how acetate facilitated 5-HT synthesis and secretion.It unveiled that acetate orchestrates signaling pathways(phosphoinositide 3-kinase-protein kinase B(PI3K-AKT),phospholipase C-phosphorylated extracellular signal-regulated kinase(PLC-pERK),and PLC-1,4,5-trisphosphate(IP3)-Ca^(2+))within EC,enabling 5-HT production.These findings elucidate the biochemical mechanisms behind specific probiotics’effects,aiding in the targeted selection of similar beneficial strains.This study offers theoretical support for choosing probiotics with analogous functionalities based on their physiological impacts.
基金Projects(52372284,52275187,62004143)supported by the National Natural Science Foundation of ChinaProject(2022BAA084)supported by the Key R&D Program of Hubei Province,ChinaProject(232300421135)supported by the Natural Science Foundation of Henan Province,China。
文摘Mo_(2)CT_(x)MXene is a novel two-dimensional material,which is generally made by the etching of inorganic acid solutions,such as hydrofluoric acid(HF)or hydrochloric acid(HCl).Those solutions are always corrosive and hazardous.In this paper,a mild organic acid,acetic acid(CH_(3)COOH),was selected to synthesize Mo_(2)CT_(x)MXene.30 mL acetic acid(HAc)with the concentration of 13 mol/L was mixed with 2 g acetate(CH_(3)COONa or CH_(3)COOK)and 10 mL water to make etching solution(NaAc+HAc or KAc+HAc).In the solution,the concentration of CH_(3)COO^(-)was 10 mol/L,the concentration of Na^(+)/K^(+)is 0.6/0.5 mol/L.The pH value is 2.8.Mo_(2)CT_(x)was obtained by hydrothermal etching at 240℃for 1 d.Compared with the general method of HF etching,the etchant is milder and the etching process is safer.On the surface of Mo_(2)CT_(x)nanosheet made by this method,acetate group(CH_(3)COO^(-))was adsorbed as termination,which is larger than the F/O/OH termination of that made by general HF etching.The lattice parameter c(LP c)of Mo_(2)CT_(x)etched with NaAc+HAc/KAc+HAc is 21.09Å/20.89Å.Moreover,the specific surface areas of the samples etched by NaAc+HAc and KAc+HAc were 18.1 m^(2)/g and 14.1 m^(2)/g,respectively,which were much larger than those etched by conventional methods.As the anode of lithium-ion battery,the specific capacity under current density of 100 mA/g at 100 th cycle was 108 mA·h/g,which is higher than the capacity of samples made by general HF etching.This work reports a novel method to make Mo_(2)CT_(x)MXene by the solution of mild acetic acid.The samples made by this method had very high specific surface area and relatively high lithium-storage performance.
基金supported by the National Natural Science Foundation of China(Nos.52174239 and 52374259)the Program of China Scholarship Council(No.202406080114)Natural Sciences and Engineering Research Council of Canada(No.NSERC RGPIN 2024-04570).
文摘Chalcopyrite is often intergrown with talc,which,after grinding,forms ultrafine particles(<10μm)that readily coat chalcopyrite surfaces,hindering flotation and causing significant losses in tailings.This study evaluates polyvinyl acetate(PVAc),a thermoplastic polymer,as a selective flocculant to enhance reverse flot ation separation of chalcopyrite from ultrafine talc.Flotation tests showed that at a PVAc dosage of 40 mg/L,talc can be effectively and selectively removed,enabling efficient separation.Laser particle size analysis and scanning electron microscopy-energy dispersive spectrometry(SEM-EDS)confirmed that PVAc promotes selective talc aggregation without affecting chalcopyrite.X-ray photoelectron spectroscopy(XPS)and density functional theory(DFT)calculations revealed that hydrogen bonding between PVAc ester groups and surface hydroxyls on talc drives the flocculation,while chalcopyrite lacks suitable binding sites.PVAc adsorption also enhances talc hydrophobicity.Furthermore,particle-bubble coverage angle measurements and extended Derjaguin-Landau-Verwey-Overbeek(DLVO)theory theoretical calculations demonstrated that PVAc-induced flocculation increases attractive interactions between talc and bubbles,shifting the total interaction energy from repulsive to attractive and promoting bubble-particle attachment.This study clarifies the selective adsorption and flocculation mechanisms of PVAc and reveals the coupling of flocculation and flotation of ultrafine talc from a particle-bubble capture perspective,while expanding the potential of ester-based polymers for ultrafine mineral recovery.
基金the Deanship of Scientific Research at King Saud University for funding the work through the research group project,No.PRG-1436-02
文摘Lead （Pb） is one of the most common environmental toxicants, exposure to which can cause significant neurotoxicity and an associated decline in brain function. This study investigated the possible neuroprotective role oflndigofera oblongifolia leaf methanolic extract （IOLME） against lead-induced neurotoxicity. Rats were intraperitoneally injected with lead acetate, with or without IOLME （intragastric administration for 5 days）, and the neuroprotective effect of IOLME was assessed by measuring the lead concentration, redox status （lipid peroxidation, nitric oxide and glutathione）, enzymatic antioxidant activities （superoxide dismutase, catalase, glutathione peroxidase and reductase）, PCR assays of apoptosis markers （Bax and Bcl-2） and histopathology of the brain. The increases in the lipid peroxidation, nitric oxide, and apoptosis, the decreases in the glutathione level and the activity of antioxidant enzymes, and the altered histology of the brain induced by lead acetate were mitigated in the brain of rats pre-treated with IOLME. These findings indicate that IOLME has beneficial effects and it mitigates lead acetate-induced neurotoxicity via its antiox-idant and anti-apoptotic activities.
基金supported by the National Natural Science Foundation of China(22378065,22278077 and 22278076)the Key Program of Natural Science Foundation of Fujian Province of China(2022J02019).
文摘The production of high-purity propylene glycol monomethyl ether acetate(PMA)through the transesterification of propylene glycol monomethyl ether(PM)and methyl acetate(MeOAc)is traditionally catalyzed by sodium methoxide.However,the practical application of this method is significantly hindered by the inherent limitations of sodium methoxide,such as its high sensitivity to moisture and propensity for solid precipitation,which impede its effective use in continuous processes.This work proposed a continuous catalytic distillation(CD)process utilizing Amberlyst 15 cation exchange resin as the catalyst.A comprehensive series of reaction kinetic and CD experiments were conducted to evaluate the performance of the proposed process.The results demonstrate that under the optimal operating conditions,namely an ester-to-ether molar ratio of 6:1,a refluxratio of 5:1,a total feed rate of 0.92 g‧min^(-1),and an evaporation rate of 266.47 m^(3)‧m^(-2)‧h^(-1),the conversion rate of PM achieves 99.95%,and the PMA yield is 97.31%.Based on these findings,a process flowsheet for a continuous CD process tailored for the production of electronic-grade PMA is presented.This design incorporates light and heavy removal steps to ensure the production of PMA with a purity of 99.99%.Additionally,the process utilizes pressure swing distillation to recover MeOAc,thereby enhancing the overall efficiencyand sustainability of the production process.The proposed continuous CD process offers a highly efficient,cost-effective,and environmentally sustainable solution for the production of electronic-grade PMA.
文摘Dear Editor： Pergularia daemia Forsk （Asclepiadaceae） is a perennial twining herb commonly known as veliparuthi in Tamil. The plant has anthelmintic, laxative, antidiabetic, hepatoprotective and anti-inflammatory activities. The pharmacological properties of this plant come from bioactive phytochemicals such as alkaloids, triterpenes, saponins and flavonoids. Phytochemically, the plant has been investigated for the presence of cardenolides, alkaloids, saponins and steroidal compoundst. In the present study, we developed a rapid method for identification and quantitative determination of putative phyto compounds in the crude extracts of ethyl acetate and methanol from whole plant of Pergularia daemia.
基金supported by the National Key Research and Development Program of China(No.2021YFA1500401)National Natural Science Foundation of China(NSFC,Nos.21821003,22371304+3 种基金223B2123)Fundamental Research Funds for the Central Universities,Sun Yat-Sen University(No.24lgzy006)Science and Technology Innovation Special Support Project of Guangdong Province,China(No.STKJ2023078)the Guangzhou Science and Technology Program(No.SL2023A04J01767)。
文摘The efficient production of acetate through electrochemical CO_(2)reduction reaction(eCO_(2)RR)with low energy consumption has consistently been a challenging yet extremely significant task.Current catalysts suffered from high energy consumption and low relative purity of acetate product.Herein,we report ultrasmall Cu_(2)O nanoparticles with an average size of 2.5±0.09 nm immobilized on a conductive copper-based metal-organic framework(Cu-THQ)(denoted as Cu_(2)O@Cu-THQ),which attained a Faradaic efficiency of 65(3)%for acetate at a very low potential of-0.3 V vs.RHE with a current density of 10.5 m A/cm^(2).Importantly,as there are no other liquid phase products such as formate,methanol or ethanol,the relative purity of the obtained acetate product was as high as 100%.Taking into account the relative purity of the liquid product,current density,and energy consumption,the performance for electroreduction of CO_(2)to acetate of Cu_(2)O@Cu-THQ is not only much higher than that of the commercial Cu_(2)O nanoparticles,but also higher than those of all reported catalysts.Operando infrared spectroscopy and theoretical calculations indicated that the synergy effect between Cu-THQ and Cu_(2)O promoted the e CO_(2)RR to yield acetate.Specifically,the hydroxyl group on the organic ligand THQ in the Cu-THQ formed hydrogen bond interactions with the key C_(2)intermediates(*CH_(2)COOH and*HOCCOH)adsorbed on Cu_(2)O,which played a crucial role in stabilizing the key C_(2)intermediates and thus reduced the formation energy of the key C_(2) intermediates.
基金supported by the National Natural Science Foundation of China(No.22276062)the Guangdong Science and Technology Program,China(No.2020B121201003).
文摘Secondary aluminum dross(SAD)is a rich source of recyclable aluminum but poses considerable risk due to its high AlN con-tent.Therefore,thoroughly removing AlN is essential,but intricate aluminum components and expensive additives pose challenges to the process.In this study,waste sodium acetate is proposed as an environmentally friendly additive for completely removing AlN and enhancing the extraction of aluminum from SAD.Through the exothermic decomposition of NaAc,reactions can occur at 850℃.AlN removal efficiency reached 93.19%after sintering,whereas Al leaching efficiency in the subsequent leaching process reached 90.49%,which were 37.86%and 375.26%higher than the removal efficiency of the control,respectively.These favorable results were attributed to the comprehensive transformation of aluminum species.The formation of soluble phase Na_(1.95)Al_(1.95)Si_(0.05)O_(4) occurred during the destruction of the Al_(2)O_(3) layer surrounding AlN and the transformation of other aluminum components.AlN decomposed upon contact with NaAc.There-fore,this study utilizes the decomposition properties of NaAc to provide an efficient and environmentally friendly route for removing AlN and extracting Al from SAD.
基金supported by the National Natural Science Foundation of China(No.52473026)。
文摘Flexible polymer-based foam sensors have significant potential for application in wearable electronics and motion monitoring.However,these prospects are hindered by the complex and unenvironmentally friendly manufacturing processes.In this study,we employed melt blending and supercritical carbon dioxide foaming to fabricate an ethylene-vinyl acetate copolymer(EVA)/low-density polyethylene(LDPE)/carbon nanotube(CNT)piezoresistive foam sensor.The cross-linking agent bis(tert-butyldioxyisopropyl)benzene and the conductive filler CNT were incorporated into the EVA/LDPE composite,successfully achieving a chemically cross-linked and physically entangled composite structure that significantly enhanced the storage modulus and complex viscosity.Additionally,the compressive strength of EVA/LDPE/CNT foam with 10 parts per hundred rubber(phr)CNT reached 1.37 MPa at 50%compression,marking a 340%increase compared to the 0.31 MPa of the CNT-free sample.Furthermore,the EVA/LDPE/CNT composite foams,which incorporated 10 phr CNT,were prepared under specific foaming conditions,resulting in an ultra-low density of 0.11 g/cm^(3) and a higher sensitivity,with a gauge factor of–2.3.The piezoresistive foam sensors developed in this work could accurately detect human motion,thereby expanding their applications in the field of piezoresistive foam sensors and providing an effective strategy for the advancement of high-performance piezoresistive foam sensors.
基金Supported by National Key R&D Program of China(2022YFA1503400)。
文摘Aiming at the problems of insufficient activity and selectivity of Cu-based catalysts in CO_(2)hydrogenation to methanol,Al_(2)O_(3),ZrO_(2)and CeO_(2)modified Cu-ZnO catalysts by the co-precipitation method were prepared,and the influence mechanism of additives on the structure-performance relationship of the catalysts was systematically explored.Through a variety of characterization methods such as XRD,N2 physical adsorption-desorption,TEM,H_(2)-TPR,CO_(2)-TPD and XPS,combined with catalytic performance evaluation experiments,the correlation between the microstructure of catalysts and the reaction performance of CO_(2)hydrogenation to methanol was analyzed in depth.The results show that metal additives significantly improve the performance of catalysts.After the introduction of additives,the specific surface area and pore volume of the catalysts increase,the grain size of Cu decreases,and its dispersion improves.The Ce-modified CZC catalyst exhibited the best performance,with the grain size of CuO as small as 11.41 nm,and the surface oxygen vacancy concentration(OⅡ/OⅠ=3.15)was significantly higher than that of other samples.The reaction performance test shows that under the conditions of 2.8 MPa,8000 h−1 and 280℃,the CO_(2)conversion of the CZC catalyst reached 18.83%,the methanol selectivity was 68.40%,and the methanol yield was 12.88%,all of which are superior to other catalysts.Its excellent performance can be attributed to the fact that CeO_(2)enhances the metal-support interaction,increases the surface basicity,promotes the adsorption and activation of CO_(2),and simultaneously inhibits the reverse water-gas shift side reaction.This study clarifies the structure-activity regulation mechanism of additive modification on Cu-ZnO catalysts,providing a theoretical basis and technical reference for the development of efficient catalysts for CO_(2)hydrogenation to methanol.
基金Supported by National Natural Science Foundation of China(21991093)。
文摘The coupling reactions of methanol and long-chain alkanes(n-dodecane,n-tetradecane and n-hexadecane)over CHA-type molecular sieves were studied in a fixed bed reactor.Over SAPO-34 and SSZ-13,it was found that the induction period of methanol conversion was shortened by the introduction of long-chain alkanes.However,the addition of long-chain alkanes had little influence on the product distribution.Polymethylbenzenes and the derivatives were the main retained species on spent SSZ-13 catalyst,while adamantanes were the main retained species on SAPO-34.This indicates that coking species formation was mainly related to the further transformation of long-chain alkane/methanol coupling products at acid sites of the molecular sieve.These findings provide valuable information of long chain alkanes conversion and methanol reaction behavior of induction period over small pore CHA molecular sieves.
