Synthesis of mordenite by solvent-free method and its application in the dimethyl ether carbonylation reaction

Mordenite with different Si/Al ratios were synthesized by solvent-free method and used for dimethyl ether(DME)carbonylation reaction.The influence of Si/Al ratio in the feedstock on the structure,porosity and acid sites were systematically investigated.The characterization results showed that with the increase of Si/Al ratio in the feedstock,part of silicon species fail to enter the skeleton and the specific surface area and pore volume of the samples decreased.The amount of weak acid and medium strong acid decreased alongside with the increasing Si/Al ratio,and the amount of strong acid slightly increased.The Al atoms preferentially enter the strong acid sites in the 8 member ring(MR)channel during the crystallization process.The high Si/Al ratio sample had more acid sites located in the 8 MR channel,leading to more active sites for carbonylation reaction and higher catalytic performance.Appropriately increasing the Si/Al ratio was beneficial for the improvement of carbonylation reaction activity over the mordenite(MOR)catalyst.

High performance photodegradation resistant PVA@TiO_(2)/carboxyl-PES self-healing reactive ultrafiltration membrane

The occurrence of ultrafiltration(UF)membrane fouling frequently hampers the sustainable advancement of UF technology.Reactive self-cleaning UF membranes can effectively alleviate the problem of membrane fouling.Nevertheless,the self-cleaning process may accelerate membrane aging.Addressing these concerns,we present an innovative design concept for composite self-healing materials based on self-cleaning UF membranes.To begin,TiO_(2)nanoparticles were incorporated into the polymer molecular structure via molecular design,resulting in the synthesis of TiO_(2)/carboxyl-polyether sulfone(PES)hybrid materials.Subsequently,the nonsolvent-induced phase inversion technique was employed to prepare a novel of UF membrane.Lastly,a polyvinyl alcohol(PVA)hydrogel coating was applied to the hybrid UF membrane surface to create PVA@TiO_(2)/carboxyl-PES self-healing reactive UF membranes.By establishing a covalent bond,the TiO_(2)nanoparticles were effectively and uniformly dispersed within the UF membrane,leading to exceptional self-cleaning properties.Furthermore,the water-absorbing and swelling properties of PVA hydrogel,along with its capacity to form hydrogen bonds with water molecules,resulted in UF membranes with improved hydrophilicity and active self-healing abilities.The results demonstrated that the water contact angle of PVA@5%TiO_(2)/carboxyl-PES UF membrane was 43.1°.Following a 1-h exposure to simulated solar exposure,the water flux recovery ratio increased from 48.16%to 81.03%.Moreover,even after undergoing five cycles of 12-h simulated sunlight exposure,the UF membranes exhibited a consistent retention rate of over 97%,thus fully demonstrating their exceptional self-cleaning,antifouling,and selfhealing capabilities.We anticipate that the self-healing reactive UF membrane system will serve as a pioneering and comprehensive solution for the self-cleaning antifouling challenges encountered in UF membranes while also effectively mitigating the aging effects of reactive UF membranes.

Interfacial engineering through lead binding using crown ethers in perovskite solar cells

In the domain of perovskite solar cells(PSCs),the imperative to reconcile impressive photovoltaic performance with lead-related issue and environmental stability has driven innovative solutions.This study pioneers an approach that not only rectifies lead leakage but also places paramount importance on the attainment of rigorous interfacial passivation.Crown ethers,notably benzo-18-crown-6-ether(B18C6),were strategically integrated at the perovskite-hole transport material interface.Crown ethers exhibit a dual role:efficiently sequestering and immobilizing Pb^(2+)ions through host-guest complexation and simultaneously establishing a robust interfacial passivation layer.Selected crown ether candidates,guided by density functional theory(DFT)calculations,demonstrated proficiency in binding Pb2+ions and optimizing interfacial energetics.Photovoltaic devices incorporating these materials achieved exceptional power conversion efficiency(PCE),notably 21.7%for B18C6,underscoring their efficacy in lead binding and interfacial passivation.Analytical techniques,including time-of-flight secondary ion mass spectrometry(ToF-SIMS),ultraviolet photoelectron spectroscopy(UPS),time-resolved photoluminescence(TRPL),and transient absorption spectroscopy(TAS),unequivocally affirmed Pb^(2+)ion capture and suppression of non-radiative recombination.Notably,these PSCs maintained efficiency even after enduring 300 h of exposure to 85%relative humidity.This research underscores the transformative potential of crown ethers,simultaneously addressing lead binding and stringent interfacial passivation for sustainable PSCs poised to commercialize and advance renewable energy applications.

The effect of salt anion in ether‐based electrolyte for electrochemical performance of sodium‐ion batteries:A case study of hard carbon

Compared with the extensively used ester‐based electrolyte,the hard carbon(HC)electrode is more compatible with the ether‐based counterpart in sodium‐ion batteries,which can lead to improved cycling stability and robust rate capability.However,the impact of salt anion on the electrochemical performance of HC electrodes has yet to be fully understood.In this study,the anionic chemistry in regulating the stability of electrolytes and the performance of sodium‐ion batteries have been systematically investigated.This work shows discrepancies in the reductive stability of the anionic group,redox kinetics,and component/structure of solid electrolyte interface(SEI)with different salts(NaBF_(4),NaPF_(6),and NaSO_(3)CF_(3))in the typical ether solvent(diglyme).Particularly,the density functional theory calculation manifests the preferred decomposition of PF_(6)−due to the reduced reductive stability of anions in the solvation structure,thus leading to the formation of NaF‐rich SEI.Further investigation on redox kinetics reveals that the NaPF_(6)/diglyme can induce the fast ionic diffusion dynamic and low charge transfer barrier for HC electrode,thus resulting in superior sodium storage performance in terms of rate capability and cycling life,which outperforms those of NaBF_(4)/diglyme and NaSO_(3)CF_(3)/diglyme.Importantly,this work offers valuable insights for optimizing the electrochemical behaviors of electrode materials by regulating the anionic group in the electrolyte.

Amine-functionalized metal organic framework@graphene oxide as filler in PAEK-containing carboxyl group membrane for ultrafiltration with ultra-high permeability and strong fouling resistance

Achieving high fouling resistance and permeability using membrane separation technology in water treatment processes remains a challenge.In this work,a novel mixed-matrix membrane(MMM)(poly(arylene ether ketone)[PAEK]-containing carboxyl groups[PAEK-COOH]/UiO-66-NH_(2)@graphene oxide[GO])with superb fouling resistance and high permeability was prepared by the nonsolvent-induced phase separation method,by in-situ growth of UiO-66-NH_(2) on the GO layer,and by preparing hydrophilic PAEK-COOH.On the basis of the structure and performance analysis of the MMM,the maximum water flux reached 591.25 L·m^(-2)·h^(-1) for PAEK-COOH/UiO-66-NH_(2)@GO,whereas the retention rate for bovine serum albumin increased from 85.40%to 94.87%.As the loading gradually increased,the hydrophilicity of the MMMs increased,significantly enhancing their fouling resistance.The strongest anti-fouling ability observed was 94.74%,which was 2.02 times greater than that of the pure membrane.At the same time,the MMMs contained internal amide and hydrogen bonds during the preparation process,forming a cross-linked structure,which further enhanced the mechanical strength and chemical stability.In summary,the MMMs with high retention rate,strong permeability,and anti-fouling ability were successfully prepared.

TLC Identification and Extraction Process of Rubiasin-1-methyl Ether from Yao Medicine Chuanlianzhu

[Objectives]To establish a thin-layer chromatography(TLC)method for the determination of rubiadin-1-methyl ether in Yao Medicine Chuanlianzhu(Damnacanthus giganteus).[Methods]A silica gel G thin-layer plate was adopted for TLC.Petroleum ether(60-90℃)-chloroform-methanol-water(7:15:3:1)was used as the developing solvent and inspected under ultraviolet lamp(365 nm).The content was determined by Inertsil ODS-3 C 18 column(4.60 mm×250 mm,5μm),mobile phase:acetonitrile-0.2%phosphoric acid gradient elution,detection wavelength 277 nm,flow rate 1.0 mL/min,column temperature 30℃,injection volume 10μL.[Results]The spots of 10 Chuanlianzhu samples from different origins showed the same color at the same position as the control,and the spots were clear and specific.The injection volume of rubiadin-1-methyl ether showed a good linear relationship in the range of 2.90-145μg(R=0.9996).The average recovery rate of rubiadin-1-methyl ether in the low,medium and high dose groups of Yao Medicine Chuanlianzhu was 98.72%,and RSD=1.78%.[Conclusions]This method can effectively identify Yao Medicine Chuanlianzhu medicinal materials and accurately determine the content of rubiadin-1-methyl ether in the medicinal materials.It provides a scientific basis for the development and utilization of Yao Medicine Chuanlianzhu medicinal resources.

Economy, environmental assessment and energy conservation for separation of isopropanol/diisopropyl ether/water multi-azeotropes via extractive distillation coupled pervaporation process

This wok proposed the extraction distillation coupled pervaporation(ED+PV) technology process using two different solvents to separate isopropanol(IPA) and diisopropyl ether(DIPE) from DIPE/IPA/H_(2)O ternary heterogeneous azeotropes in industrial wastewater from the synthesis of isopropanol in this study.Based on strict design specifications, simulation and sequential iteration methods are used for process design and optimization. Compared to the ethylene glycol(EG)-EG+H_(2)O process and the 1,3-propanediol(PDO)-IPA+H_(2)O process, the total annual cost(TAC) of the EG-IPA+H_(2)O process decreased by 20.76% and 7.86%(PDO). Compared to the EG-EG+H_(2)O process, the TAC of the PDO-IPA+H_(2)O process reduced 14%, but the global warming potential(GWP) and human toxicity of the PDO-IPA+H_(2)O process increased 11.3% and 4.07% respectively. Compared to the PDO-IPA+H_(2)O process, the EG-IPA+H_(2)O process saves 7.86%(TAC), 9.78%(GWP) and 9.85%(human toxicity). The ED+PV process with EG is superior to PDO in factors of TAC, energy consumption, human toxicity and environment. The EG-IPA+H_(2)O process changed the separation order of the products of the multi-azeotropic system, reduced the cost and energy conservation of the system, and enhanced the environmental protection evaluation of the process, is the best process through life cycle assessment for analyzing the economy, energy conservation, environmental assessment and human toxicity, designing cleaner products, controlling waste discharge, and promoting the chemical purification industry. This work provides a new process design and optimized separation ideas, will have a good guiding significance for the research and application separation of multi-azeotropic mixture with mixed solvents in organic wastewater from the cleaner chemical production, has been up to standard wastewater discharge process, and realized the development goal of carbon peak and carbon neutrality in the sustainable development of chemical clean industry.

基于AC810 PLC控制的岸边集装箱起重机电控系统设计

为解决集装箱装卸设备的电控系统技术不能自主可控的问题,采用AC810系列PLC作为控制中心,基于Ether CAT现场总线技术,研发了完全国产化的岸边集装箱起重机和门座起重机电控系统。现场运行结果表明,该电控系统可实现港口装卸设备自动化操作,有效降低集装箱运输中发生危险的概率,提高码头集装箱运输的工作效率。

Harnessing dimethyl ether and methyl formate fuels for direct electrochemical energy conversion

In this work,the oxidation of a mixture of dimethyl ether(DME) and methyl formate(MF) was studied in both an aqueous electrochemical cell and a vapor-fed polymer electrolyte membrane fuel cell(PEMFC)utilizing a multi-metallic alloy catalyst,Pt_(3)Pd_(3)Sn_(2)/C,discovered earlier by us.The current obtained during the bulk oxidation of a DME-saturated 1 M MF was higher than the summation of the currents provided by the two fuels separately,suggesting the cooperative effect of mixing these fuels.A significant increase in the anodic charge was realized during oxidative stripping of a pre-adsorbed DME+MF mixture as compared to DME or MF individually.This is ascribed to greater utilization of specific catalytic sites on account of the relatively lower adsorption energy of the dual-molecules than of the sum of the individual molecules as confirmed by the density fu nctional theory(DFT) calculations.Fuel cell polarization was also conducted using a Pt_(3)Pd_(3)Sn_(2)/C(anode) and Pt/C(cathode) catalysts-coated membrane(CCM).The enhanced surface coverage and active site utilization resulted in providing a higher peak power density by the DME+MF mixture-fed fuel cell(123 mW cm^(-2)at 0.45 V) than with DME(84mW cm^(-2)at 0.35 V) or MF(28 mW cm^(-2)at 0.2 V) at the same total anode hydrocarbon flow rate,temperature,and ambient pressure.

Durable semi-crystalline interphase engineering to stabilize high voltage Ni-rich cathode in dilute ether electrolyte

Ethers are promising electrolyte solvents for secondary Li metal batteries because of their excellent reduction stability.However,their oxidation stability has been mostly relying on the high concentration approach,and limited progress has been made on building effective interphase to protect the cathode from the corrosion of the electrolyte.In this work,we construct a semi-crystalline interfacial layer on the surface of Li(Ni_(0.8)Co_(0.1)Mn_(0.1))O_(2)cathode that can achieve improved electrochemical stability in the highly corrosive chemical environment formed by the decomposition of ether molecules.Different from traditional brittle crystalline interphases,the optimized semi-crystalline layer with low modulus and high ionic conductivity can effectively relieve electrode strain and maintain the integrity of the interface layer.Due to this design,the continuous oxidation decomposition of ether-based electrolytes could be significantly suppressed and the battery shows outstanding cycling stability(84%capacity retention after 300 cycles).This article provides a solution to address the oxidation instability issue of ether-based electrolytes.

Butyl ether as Co-diluent in medium-concentrated electrolyte for Li-S battery

1. Introduction The Lithium-sulfur battery(LSB) shows promise as a highdensity energy source, with a theoretical energy density of approximately 2600 W h kg^(-1)[1]. However, practical application of the LSB has been hindered by the “shuttle effect” and Li anode corrosion [2,3]. Highly concentrated electrolytes(HCEs) have been proposed as a solution, as they can inhibit the dissolution of lithium polysulfide and promote homogeneous lithium deposition [4].

Li^(+)-ion bound crown ether functionalization enables dual promotion of dynamics and thermodynamics for ambient ammonia synthesis

Electrosynthesis of ammonia from the reduction of nitrogen is still confronted with the limited supply of gas reactant in dynamics as well as high activation barrier in thermodynamics.Unfortunately,despite tremendous efforts devoted to electrocatalysts themselves,they still fail to tackle the above two challenges simultaneously.Herein,we employ a heterogeneous catalyst adlayer-composed of crown ethers associated with Li^(+)ions-to achieve the dual promotion of dynamics and thermodynamics for ambient ammonia synthesis.Dynamically,the bound Li^(+)ions interact with the strong quadrupole moment of nitrogen,and trigger considerable reactant flux toward the catalyst.Thermodynamically,Li^(+)associated with the oxygen of crown ether achieves a higher density of states at the Fermi level for the catalyst,enabling effortless electron transfer from the catalysts to nitrogen and thus greatly reducing the activation barrier.As expected,the proof-of-concept system achieves an ammonia yield rate of 168.5μg h^(-1)mg^(-1)and a Faradaic efficiency of 75.3%at-0.3 V vs.RHE.This system-level approach opens up pathways for tackling the two key challenges that have limited the field of ammonia synthesis.

Density Functional Theory Study of Marine Polybrominated Diphenyl Ethers in Anaerobic Degradation

Polybrominated diphenyl ethers(PBDEs)are a kind of serious pollutants in the ocean.Biodegradation is considered as an economical and safe way for PBDEs removal and reductive debromination dominates the initial pathway of anaerobic degradation.On the basis of experimental study,Octa-BDE 197,Hepta-BDE 183,Hexa-BDE 153,Penta-BDE 99 and Tetra-BDE 47 were selected as the initial degradation objects,and their debromination degradation were studied using density functional theory.The structures were optimized by Gaussian 09 program.Furthermore,the molecular orbitals and charge distribution were analyzed.All C-Br bond dissociation energies at different positions including ortho,meta and para bromine atoms were calculated and the sequence of debromination was obtained.There is a close relationship between molecular structure,charge,molecular orbital and C-Br bond.All PBDEs exhibited similar debromination pathways with preferential removal of meta and para bromines.

Functional zirconium phosphate nanosheets enabled transfer hydrogenolysis of aromatic ether bonds over a low usage of Ru nanocatalysts

Catalytic hydrogenolysis of aromatic ether bonds is a highly promising strategy for upgrading lignin into small-molecule chemicals,which relies on developing innovative heterogeneous catalysts with high activity.Herein,we designed porous zirconium phosphate nanosheet-supported Ru nanocatalysts(Ru/ZrPsheet)as the heterogeneous catalyst by a process combining ball milling and molten-salt(KNO_(3)).Very interestingly,the fabricated Ru/ZrPsheetshowed good catalytic performance on the transfer hydrogenolysis of various types of aromatic ether bonds contained in lignin,i.e.,4-O-5,a-O-4,β-O-4,and aryl-O-CH3,over a low Ru usage(<0.5 mol%)without using any acidic/basic additive.Detailed investigations indicated that the properties of Ru and the support were indispensable.The excellent activity of Ru/ZZrPsheetoriginated from the strong acidity and basicity of ZrPsheetand the higher electron density of metallic Ru0as well as the nanosheet structure of ZrPsheet.

A Janus separator towards dendrite-free and stable zinc anodes for long-duration aqueous zinc ion batteries

Critical issues of Zn anodes including undesirable dendrites formation and parasitic reactions severely limit the reversibility and cyclability of Zn anodes.To address these issues,a functional Janus separator with the structure of a mechanically strong sulfonated poly(arylene ether sulfone)(SPAES)dense layer composited on a porous glass fiber(GF)substrate is designed.The SPAES dense layer that faces the Zn anode containing abundant sulfonic acid groups effectively promotes the desolvation process of hydrated Zn ions,guides uniform Zn ion transfer,and blocks anions and water,contributing to dendrite-free and highly reversible Zn plating/stripping cycles,while the porous GF substrate retains high electrolyte uptake.As a result,the Zn symmetric cell with the Janus separator demonstrates an ultralong cycling lifespan of over 2000 h at the areal capacity of 1 m A h cm^(-2),which is 23-fold superior to that with a pristine glass fiber separator(<90 h).More impressively,the as-prepared Janus separator enables outstanding rate performance and excellent cycling stability of full Zn ion batteries with diverse cathode materials.For instance,when paired with the V_2O_(5)cathode,the full battery with a Janus separator attains an ultrahigh initial specific capacity of 416.3 m A h g^(-1)and capacity retention of 60%over 450 cycles at 1 A g^(-1),exceeding that with a glass fiber separator.Hence,this work provides a facile yet effective approach to mitigating the dendrites formation and ameliorating the parasitic reactions of Zn metal anodes for high-performance Zn ion batteries.

A dilute fluorine-free electrolyte design for high-voltage hybrid aqueous batteries

Fluorinated salts and/or high salt concentrations are usually necessary to produce protective films on the electrodes for high-voltage aqueous batteries,yet these approaches increase the cost,toxicity and reaction resistances of battery.Herein,we report a dilute fluorine-free electrolyte design to overcome this dilemma.By using the LiClO_(4) salt and polyethylene glycol dimethyl ether(PED)solvent and optimizing the LiClO_(4)/PED/H_(2)O molar ratio,we formulate a 1 mol kg^(-1)3 V-class hybrid aqueous electrolyte that enables reversible charge/discharge of 2.5 V LiMn_(2)O_(4)|Li_(4)Ti_(5)O_(12) full cell at both low(0.5C,92.4%capacity retention in 300 cycles)and high(5C,80.4%capacity retention in 2000 cycles)rates.This excellent performance is reached even without the generation of protective film on either anode or cathode as identified by in/ex situ characterizations.The selection of appropriate ingredients that have both high stability and strong interactions with water is critical to widen the potential window of electrolyte while suppressing parasitic reactions on the electrodes.This work suggests that expensive and toxic fluorinate salts are no longer necessary for 3 V-class aqueous electrolytes,boosting the development of low-cost,environmentally-friendly,high-power and high-energy-density aqueous batteries.

Preparation of Hydrophobic Fly Ash by Surface Modification and Oil-water Separation Devices

A simple and effective superhydrophobic mesh was designed and made to separate oil-water mixture. Alkali-activated fly ash reacted with 1-bromooctadecane to prepare superhydrophobic modified fly ash (MFA) with low surface energy through Williamson ether synthesis. The MFA powder was then coated uniformly on a stainless steel mesh (SSM) along with the epoxy resin E44 and curing agent T31 to give the superhydrophobic MFA-modified stainless steel mesh (MFA-SSM). The MFA-SSM has a high static water contact angle (CA) of 150.1°and can separate various oil or organic solvent from water with>95%separation efficiency. The oil-water separation efficiency remained high after 30 runs of petroleum ether/water separation.The developed superhydrophobic stainless steel mesh is expected to have wider use in oil-water separation.

Concentrated ternary ether electrolyte allows for stable cycling of a lithium metal battery with commercial mass loading high-nickel NMC and thin anodes

A new concentrated ternary salt ether-based electrolyte enables stable cycling of lithium metal battery(LMB)cells with high-mass-loading(13.8 mg cm^(−2),2.5 mAh cm^(−2))NMC622(LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2))cathodes and 50μm Li anodes.Termed“CETHER-3,”this electrolyte is based on LiTFSI,LiDFOB,and LiBF4 with 5 vol%fluorinated ethylene carbonate in 1,2-dimethoxyethane.Commer-cial carbonate and state-of-the-art binary salt ether electrolytes were also tested as baselines.With CETHER-3,the electrochemical performance of the full-cell battery is among the most favorably reported in terms of high-voltage cycling stability.For example,LiNi_(x)Mn_(y)Co_(1-x-y)O_(2)(NMC)-Li metal cells retain 80%capacity at 430 cycles with a 4.4 V cut-off and 83%capacity at 100 cycles with a 4.5 V cut-off(charge at C/5,discharge at C/2).According to simulation by density functional theory and molecular dynamics,this favorable performance is an outcome of enhanced coordination between Li^(+)and the solvent/salt molecules.Combining advanced microscopy(high-resolution transmission electron microscopy,scanning electron microscopy)and surface science(X-ray photoelectron spectroscopy,time-of-fight secondary ion mass spectroscopy,Fourier-transform infrared spectroscopy,Raman spectroscopy),it is demonstrated that a thinner and more stable cathode electrolyte interphase(CEI)and solid electrolyte interphase(SEI)are formed.The CEI is rich in lithium sulfide(Li_(2)SO_(3)),while the SEI is rich in Li_(3)N and LiF.During cycling,the CEI/SEI suppresses both the deleterious transformation of the cathode R-3m layered near-surface structure into disordered rock salt and the growth of lithium metal dendrites.

A Comparative Study of the Hydroxyl Value and Iodine Value in Polyoxyl Stearyl Ether in United States Pharmacopeia Specifications

The iodine value (iodine number) and hydroxyl value are important analytical characteristics of fats and oils. The iodine (I2) required saturating the fatty acids present in 100 grams of the oil or fat. Iodine value is a measure of the total number of double bonds (-C=C-) present in fats and oils. Unsaturated compounds contain molecules with double and triple bonds which are very reactive towards iodine. The iodine value has been determined according to Hanus with iodine monobromide in glacial acetic acid, and then the amount of iodine remaining unreacted is determined by titration using sodium thiosulfate volumetric standard solution. The hydroxyl value is the amount of potassium hydroxide in milligrams that is equivalent to the hydroxyl amount of 1 gram of the sample (mg KOH/g sample). Poloxyl Stearyl Ether is a mixture of the monostearyl ethers of mixed polyethylene glycols. It may contain various amounts of free stearyl alcohol and some free polyethylene glycol. In this study, the iodine value and hydroxyl value have been determined by titration in polyoxyl stearyl ether. Iodine value 1.84 g of I2 absorbed/100g sample, and hydroxyl value 162.65 mg KOH/g sample have been found in poloxyl stearyl ether. The iodine value and hydroxyl value results met the United States Pharmacopeia specifications for Polyoxyl Stearyl Ether.

2,4-Dinitrophenyl Ether of Polyvinyl Alcohol and Polymer Bound Anionic SIGMA Complexes

A new electrophilic polymer, 2,4-dinitrophenyl ether of polyvinyl alcohol (PVA-DNP), having a degree of substitution of 0.5 was prepared from polyvinyl alcohol (PVA) and 1-fluro-2,4-dinitrobenzene (DNFB). The PVA-DNP polymer was characterized by NMR, IR, and UV-visible spectroscopy. The reaction of PVA-DNP with sodium methoxide was followed by NMR and UV-visible spectroscopy. Evidence of polymer bound spirocyclic SIGMA complex, C-1 and C-3 polymer bound DNP-methoxy SIGMA complexes and the formation and C-1 methoxy complex of 2,4-dinitroanisole was observed.