Role of methoxy and C_(α)-based substituents in electrochemical oxidation mechanisms and bond cleavage selectivity of β-O-4 lignin model compounds

In order to better understand the specific substituent effects on the electrochemical oxidation process of β-O-4 bond, a series of methoxyphenyl type β-O-4 dimer model compounds with different localized methoxyl groups, including 2-(2-methoxyphenoxy)-1-phenylethanone, 2-(2-methoxyphenoxy)-1-phenylethanol, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanol, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanol have been selected and their electrochemical properties have been studied experimentally by cyclic voltammetry, and FT-IR spectroelectrochemistry. Combining with electrolysis products distribution analysis and density functional theory calculations, oxidation mechanisms of all six model dimers have been explored. In particular, a total effect from substituents of both para-methoxy(on the aryl ring closing to Cα) and Cα-OH on the oxidation mechanisms has been clearly observed, showing a significant selectivity on the Cα-Cβbond cleavage induced by electrochemical oxidations.

Corrigendum to “Increasing the greenness of an organic acid through deep eutectic solvation and further polymerisation” [Green Energy & Environ 7 (4) (August 2022) 840–853]

The authors regret that the name of the ethic committee that approved the study and the reference number was omitted from the published paper.In this research,all animal experiments were performed in accordance with the Guide for the Care and Use of Laboratory Animals(US National Institutes of Healh)and were approved by the Animal Welfare and Ethical Committee of Hebei University(No.IACUC-2020XG021,Baoding,China).

Surface composition dominates the electrocatalytic reduction of CO2 on ultrafine CuPd nanoalloys

Preciously tuning the surface composition of noble metal nanoparticles with the particle size of only 2 nm or less by alloying with other metals represents a powerful strategy to boost their electrocatalytic selectivity.However,the synthesis of ultrafine nanoalloys and tuning their surface composition remain challenging.In this report,ultrafine CuPd nanoalloys with the particle size of ca.2 nm are synthesized based on the galvanic replacement reaction between presynthesized Cu nanoparticles and Pd2+precursors,and the tuning of their surface compositions is also achieved by changing the atom ratios of Cu/Pd.For the electrocatalytic reduction of CO2,Cu5Pd5 nanoalloys show the CO Faradaic efficiency(FE)of 88%at−0.87 V,and the corresponding mass activity reaches 56 A/g that is much higher than those of Cu8Pd2 nanoalloys,Cu3Pd7 nanoalloys and most of previously reported catalysts.Density functional theory uncovers that with the increase of Pd on the surface of the ultrafine CuPd nanoalloys,the adsorbed energy of both of intermediate COOH*and CO*to the Pd sites is strengthened.The Cu5Pd5 nanoalloys with the optimal surface composition better balance the adsorption of COOH*and desorption of CO*,achieving the highest selectivity and activity.The difficult liberation of absorbed CO*on the surface of Cu3Pd7 nanoalloys provides carbon source to favor the production of ethylene,endowing the Cu3Pd7 nanoalloys with the highest selectivity for ethylene among these ultrafine CuPd nanoalloys.

Increasing the greenness of an organic acid through deep eutectic solvation and further polymerisation

Acrylic acid(AA)is an important and widely used industrial chemical,but its high toxicity renders its use incompatible with the concept of green development.By leveraging its terminal carboxyl group and unsaturated bond,we designed and explored a new strategy to increase the greenness of AA via its eutectic melting using a quaternary ammonium salt(choline chloride)to form a deep eutectic solvent(DES),followed by polymerisation of the DES to form a polymer(poly(DES)).The greenness of AA,DES,and poly(DES)was evaluated via an in vitro test using MGC80-3 cells and an in vivo test using Kunming mice.The toxicity improved from Grade 2(moderately toxic)for AA to Grade 1(slightly toxic)for DESs and Grade 0(non-toxic)for poly(DES)in the in vitro test.Moreover,the poly(DES)s showed a lower toxicity in mice than the DESs in the in vivo test.Thus,greenness enhancement was successfully achieved,with the greenness following the order AA<DES<poly(DES).Furthermore,the mechanisms underlying the change in toxicity were explored through microscopy and flow cytometry,which revealed that the DES can permeate the MGC80-3 cell membrane during the G_(0)/G_(1) phase to adversely affect DNA synthesis in the S phase,but the poly(DES)cannot.Finally,the green poly(DES),which showed good adsorption properties and flexible functionality,was successfully applied as a carrier or excipient of drugs.Through the novel strategy reported herein,greenness enhancement and the broadening of the application scope of a toxic organic acid were achieved,making such acids applicable for green development.

Getting closer to the outstanding scientist in the field of ionic liquiddAn interview with Prof. Robin D. Rogers

Expert Profile:Prof.Robin D.Rogers is a Research Professor at The University of Alabama and President,Owner,and Founder of 525 Solutions,Inc.,in Tuscaloosa,AL USA.Prof.Robin Rogers is one of the important pioneers in the field of ionic liquids from academic research to application.He was awarded the US Presidential Green Chemistry Challenge Award in 2005.

Study of screening,transport pathway,and vasodilation mechanisms on angiotensin-Ⅰconverting enzyme inhibitory peptide from Ulva prolifera proteins

In this study,Ulva prolifera protein was used for preparing angiotensin-I converting enzyme(ACE)-inhibitory peptide via virtual gastrointestinal digestion and in silico screening.Some parameters of the obtained peptide,such as inhibition kinetics,docking mechanism,stability,transport pathway,were explored by Lineweaver-Burk plots,molecular docking,in vitro stimulate gastrointestinal(GI)digestion and Caco-2 cells monolayer model,respectively.Then,a novel anti-ACE peptide LDF(IC_(50),(1.66±0.34)μmol/L)was screened and synthesized by chemical synthesis.It was a no-competitive inhibitor and its anti-ACE inhibitory effect mainly attributable to four Conventional Hydrogen Bonds and Zn701 interactions.It could keep activity during simulated GI digestion in vitro and was transported by peptide transporter PepT1 and passive-mediated mode.Besides,it could activate Endothelial nitric oxide synthase(eNOS)activity to promote the production of NO and reduce Endothelin-1(ET-1)secretion induced by AngiotensinⅡ(AngⅡ)in Human Umbilical Vein Endothelial Cells(HUVECs).Meanwhile,it could promote mice splenocytes proliferation in a concentration-dependent manner.Our study indicated that this peptide was a potential ingredient functioning on vasodilation and enhancing immunity.

Electrolyte for lithium protection: From liquid to solid

Lithium battery with high energy density and enhanced safety is undoubtedly the ideal choice for consumer electronics and electric vehicles.Metal anode such as lithium has been considered as the most effective way to enhance the energy density as it provides ultra-high theoretical capacity and the lowest redox potential.However,due to the low coulombic efficiency as well as safety concerns originated from dendrite issue of lithium,its further commercial utilization is hindered.Dendrite growth is a common phenomenon in metal electrodeposition while the plating process of Li is more complicated than other metals for its high reactivity nature.As a matter of fact,the Li plating process is accompanied with the generation of solid electrolyte interphase(SEI)in which the electrolyte plays a vital role.In this paper,recent advances of electrolytes for Li protect application are reviewed,from liquid to gel polymer and solid state,on which we find that although tremendous progress has been accomplished,there are still great challenges before Li metal anode could be commercially used.

Protic vs aprotic ionic liquid for CO2 fixation:A simulation study

The cycloaddition of CO2 with epoxides catalyzed by ionic liquids(ILs)has been a widely ongoing studied hot topic over the years.Recent experimental research has shown that the protic ionic liquids(PILs)behave stronger hydrogen proton donating ability than aprotic ionic liquids(APILs),and can effectively catalyze the cycloaddition of CO2.Unfortunately,the mechanistic explanation remains primarily unraveled.Herein,a detailed simulation study on the cycloaddition reaction catalyzed by PIL([HDBU][Mim])in comparison with APIL([MeDBU][Mim])re-action catalysts was conducted,including the three-step route(ring-opening of PO(propylene oxide),insertion of CO2 and ring-closure of propylene carbonate(PC))and two-step route(simultaneously ring-opening of PO and addition of CO2,and then ring-closure of PC).Based on the activation energy barrier of the rate-determining step,PIL preferentially activates PO as the optimal route for the reaction with the energy barrier of 23.2 kcal mol-1,while that of APIL is 31.2 kcal mol-1.The role of[HDBU]+in the reaction was also explored and found that the direct formation of intermolecular hydrogen bond(H-bond)between[HDBU]+and the reactants(PO+CO2)was unfavorable for the reaction,while the cooperation with the anion[Mim]-to assist indirectly was more conducive.To fully consider the reaction microenvironment of ILs,ONIOM calculation was used to study the solvent effect.At last,the above conclusions were further verified by the analysis of intermediates with charge,non-covalent interaction(NCI),and atoms in molecules(AIM)methods.The computational findings show that ILs studied in this work have dual functions of catalyst and solvent,enabling a microscopic understanding of the ILs catalyst for CO2 utilization as well as providing guidance for the rational design of more efficient ILs-based catalysts.

Recent progress of green sorbents-based technologies for low concentration CO_(2) capture

The increased concentration of CO_(2) due to continuous breathing and no discharge of human beings in the manned closed space,like spacecraft and submarines,can be a threat to health and safety.Effective removal of low concentration CO_(2) from the manned closed space is essential to meet the requirements of long-term space or deep-sea exploration,which is an international frontier and trend.Ionic liquids(ILs),as a widespread and green solvent,already showed its excellent performance on CO_(2) capture and absorption,indicating its potential application in low concentration CO_(2) capture.In this review,we first summarized the current methods and strategies for direct capture from low concentration CO_(2) in both the atmosphere and manned closed spaces.Then,the multi-scale simulation methods of CO_(2) capture by ionic liquids are described in detail,including screening ionic liquids by COSMO-RS methods,capture mechanism by density functional theory and molecular dynamics simulation,and absorption process by computational fluid dynamics simulation.Lastly,some typical IL-based green technologies for low concentration CO_(2) capture,such as functionalized ILs,co-solvent systems with ILs,and supported materials based on ILs,are introduced,and analyzed the subtle possibility in manned closed spaces.Finally,we look forward to the technology and development of low concentration CO_(2) capture,which can meet the needs of human survival in closed space and proposed that supported materials with ionic liquids have great advantages and infinite possibilities in the vital area.

A new era of precise liquid regulation:Quasi-liquid

Common in nature and artificial systems,quasi-liquid represents a special phase under specific conditions,where precise regulations can be conducted to accommodate various applications,such as material,biology,life and manufacture.

Functional characteristic and application of omega-3

Omega-3 is a group of polyunsaturated fatty acids,which are important substances in human cells and cannot be synthesized in the human body which must be taken from the outside.The definition and physiological functions of omega-3 unsaturated fatty acids(UFAs)were simply introduced in this paper.Application and significant development of omega-3 UFAs in domestic and foreign functional food were reviewed.The application prospect of omega-3 UFAs will be helpful to the development and utilization of omega-3.

Challenge and opportunity of ionic liquidsdAn interview with Prof.Douglas R.Macfarlane

Expert Profile:Prof.Douglas R.MacFarlane is an Australian Laureate Fellow at Monash University's School of Chemistry and leader of the Energy Program in the Australian Centre for Electromaterials Science.He is the Australian Academy of Science's Craig Medalist 2018 and winner of the Victoria Prize for Science and Innovation 2018.

Proliferating cell nuclear antigen of Ulva prolifera is involved in the response to temperature stress

Ulva prolifera is the most common specie causative to green tide,and its growth is sensitive to temperature stress.However,the mechanisms of U.prolifera response to temperature stress remain elusive.In this study,high temperature(36℃)stimulus promoted the death of unformed cell wall protoplasts and delayed the division of formed cell wall protoplasts,while low-temperature(4℃)stimulus did not,suggesting that the mechanisms of the response of U.prolifera to high and low temperature stresses are different.Transcriptome results show that proliferation-related genes were differentially expressed under high and low-temperature stresses,especially the proliferating cell nuclear antigen(PCNA)and cyclins(CYCs).Subsequently,the interaction between PCNA and Cyclin A was confirmed by Co-immunoprecipitation,yeast two-hybrid,and so on.Furthermore,high-and low temperature stresses induced the expression of PCNA and Cyclin A in varying of degrees,and activated extracellular signal-regulated kinase(ERK)signal pathway.These results suggest,PCNA,Cyclin A,and ERK signal pathway played important roles in the resistance of U.prolifera to temperature stress.Interestingly,high-temperature stress induced an increase of miR-2916 in abundance,and exhibiting reverse expression of PCNA;and PCNA was target gene of miR-2916,suggesting that miR-2916 protected U.prolifera from high-temperature stress via post-transcriptionally regulation of PCNA.This study laid a foundation for understanding the function of PCNA and Cyclin A,moreover,it has a guiding significance to explore the mechanisms of the response to temperature stress from proliferation-related genes regulatory networks in U.prolifera.

纳微尺度热力学与前沿应用

在实际化工过程中,纳微尺度界面体系普遍存在,且与反应和传递等过程高度耦合.这种耦合增加了直接应用宏观热力学模型和规律的难度,进而在工程预测、放大及调控方面带来挑战,制约了绿色化工技术创新和规模应用的发展.本文针对纳微尺度热力学的起源、内涵及其在前沿领域的应用进行了深入探讨.首先,以绿色介质离子液体为例,展示了纳微尺度下的独特界面结构和功能,讨论了离子液体结构–功能间的纳微尺度热力学关联机制;然后,概述了适用于纳微尺度热力学领域的研究方法,提出了集合高精度原位动态实验、精准高效计算模拟和高通量自动化人工智能相结合的研究范式;随后,总结了纳微尺度热力学理论在反应、分离和电化学领域的前沿应用,并对其挑战和未来机遇进行了深入讨论和展望.总之,纳微尺度热力学的新理论和新方法,不仅可以为化工学科的科学研究开辟新的视野和路径,还将推动化工过程实现从“分子设计→结构功能调控→工程放大规律”的跨越,催生出适应于新体系、新应用和新需求的化工热力学新学科.

Ionic liquid-trimetallic electrocatalytic system for C–O bond cleavage in lignin model compounds and lignin under ambient conditions

Electrocatalytic depolymerization of lignin into value-added chemicals offers a promising technique to make biorefining sustainable.Herein,we report a robust trimetallic PdNiBi electrocatalyst for reductive C–O bond cleavage of different lignin model dimers and oxidized lignin under mild conditions.The reduction reaction proceeds with complete substrate conversion and excellent yields toward monomers of phenols(80%–99%)and acetophenones(75%–96%)in the presence of an ionic liquid electrolyte with operational stability.Systematic experimental investigations together with density functional theory(DFT)calculations reveal that the outstanding performance of the catalyst results from the synergistic effect of the metal elements,which facilitates the easier formation of a key Cαradical intermediate and the facile desorption of the as-formed products at the electrode.The results open up new opportunities for lignin valorization through the green electrocatalytic approach.

12-Tungstophosphoric acid niched in Zr-based metal-organic framework:a stable and efficient catalyst for Friedel-Crafts acylation

Heteropoly acids(HPA) are well known for their versatile solid acid catalysis in diverse chemical reactions, however they suffer from low surface area(<10 m^2/g) and leaching into the reactions media, which reduce their prospects as industrial catalyst.Herein, a novel hybrid material HPW@Zr-BTC,composed of 12-tungstophoric acid(HPW) and Zr^(Ⅳ)-benzene tri-carboxylate(Zr-BTC) metal-organic framework(MOF), was prepared via one-pot solvothermal method. Excellent HPW loading up to 32.3 wt% was achieved, and HPW@Zr-BTC composite proved to be highly stable, besides the crystalline morphology of Zr-BTC was intact. The catalytic activity of the hybrid composite was explored via Friedel-Crafts acylation of anisole with benzoyl chloride.The 28.2 wt% HPW@Zr-BTC showed excellent catalytic performance, with 99.4% anisole conversion and 97.6% yield(pmethoxybenzophenone) under solvent free conditions. Excellent retention of catalytic activity was achieved after at least five consecutive runs due to non-observable HPW leaching. The promising activity and stability of the catalyst forecasted its potential industrial applications.

Expression Profile and Function Analysis of Long Non-coding RNAs in the Infection of Coxsackievirus B3

The roles of IncRNAs in the infection of enteroviruses have been barely demonstrated.In this study,we used coxsackievirus B3(CVB3),a typical enterovirus,as a model to investigate the expression profiles and functional roles of IncRNAs in enterovirus infection.We profiled IncRNAs and mRNA expression in CVB3-infected HeLa cells by IncRNA-mRNA integrated microarrays.As a result,700 differentially expressed IncRNAs(431 up-regulated and 269 down-regulated)and 665 differentially expressed mRNAs(299 up-regulated and 366 down-regulated)were identified in CVB3 infection.Then we performed IncRNA-mRNA integrated pathway analysis to identify potential functional impacts of the differentially expressed mRNAs,in which IncRNA-mRNA correlation network was built.According to IncRNA-mRNA correlation,we found that XLOC-001188,an IncRNA down-regulated in CVB3 infection,was negatively correlated with NFAT5 mRNA,an anti-CVB3 gene reported previously.This interaction was supported by qPCR detection following siRNA-mediated knockdown of XLOC-001188,which showed an increase of NFAT5 mRNA and a reduction of CVB3 genomic RNA.In addition,we observed that four most significantly altered IncRNAs,SNHG11,RP11-145F16.2,RP11-1023L17.1 and RP11-1021N1.2 share several common correlated genes critical for CVB3 infection,such as BRE and IRF2BP1.In all,our studies reveal the alteration of IncRNA expression in CVB3 infection and its potential influence on CVB3 replication,providing useful information for future studies of enterovirus infection.

Therapeutic strategies against bacterial biofilms

The emergence of multi-drug resistance makes bacterial infection a major threat to public health and economy.The formation of bacterial biofilms is one of the main reasons of bacterial resistance.The complexity of chemical composition and physical structure makes the elimination of mature biofilms a difficult problem.The highly antibiotic resistant property of biofilms urgently calls for potent antimicrobial agents and novel antibiofilm strategies.Researchers have made a lot of efforts in this field.Here we review the current strategies to eliminate mature biofilms and progress in related drug delivery nanosystems,with the aim of inspiring researchers to design new antibiofilm systems.

Erratum on “12-tungstophosphoric acid niched in Zr-BTC: a stable and efficient catalyst for Friedel-Crafts acylation” [Sci.China Chem., 2018, 61: 402–411]

Erratum to:Sci China Chem,2018,61:402-411,https://doi.org/10.1007/sll426-017-9182-0 For the above referenced publication[1],there is a correction in the Figure 9.Figure 9 Catalytic activity of pristine Zr-BTC(a),18.6 wt%HPW@Zr-BTC(b),25.2 wt%HPW@Zr-BTC(c).