The E3 ubiquitin ligase,carboxyl terminus of heat shock protein 70(Hsp70)interacting protein(CHIP),also functions as a co-chaperone and plays a crucial role in the protein quality control system.In this study,we aimed...The E3 ubiquitin ligase,carboxyl terminus of heat shock protein 70(Hsp70)interacting protein(CHIP),also functions as a co-chaperone and plays a crucial role in the protein quality control system.In this study,we aimed to investigate the neuroprotective effect of overexpressed CHIP on Alzheimer’s disease.We used an adeno-associated virus vector that can cross the blood-brain barrier to mediate CHIP overexpression in APP/PS1 mouse brain.CHIP overexpression significantly ameliorated the performance of APP/PS1 mice in the Morris water maze and nest building tests,reduced amyloid-βplaques,and decreased the expression of both amyloid-βand phosphorylated tau.CHIP also alleviated the concentration of microglia and astrocytes around plaques.In APP/PS1 mice of a younger age,CHIP overexpression promoted an increase in ADAM10 expression and inhibitedβ-site APP cleaving enzyme 1,insulin degrading enzyme,and neprilysin expression.Levels of HSP70 and HSP40,which have functional relevance to CHIP,were also increased.Single nuclei transcriptome sequencing in the hippocampus of CHIP overexpressed mice showed that the lysosomal pathway and oligodendrocyte-related biological processes were up-regulated,which may also reflect a potential mechanism for the neuroprotective effect of CHIP.Our research shows that CHIP effectively reduces the behavior and pathological manifestations of APP/PS1 mice.Indeed,overexpression of CHIP could be a beneficial approach for the treatment of Alzheimer’s disease.展开更多
Bay-site carboxyl functionalized perylene diimide derivative 1,7-COOH-PDI-C_(12)(PDI-COOH)was synthesized and distinct enhanced fluorescence was observed through combining with calcium ion(Ca^(2+))in THF/H_(2)O soluti...Bay-site carboxyl functionalized perylene diimide derivative 1,7-COOH-PDI-C_(12)(PDI-COOH)was synthesized and distinct enhanced fluorescence was observed through combining with calcium ion(Ca^(2+))in THF/H_(2)O solution.The assembly and fluorescence behavior of PDI-COOH/Ca^(2+)were studied in detail by changing hydration state with different concentrations.Based on the differences in assembly morphology and stoichiometric ratios of PDICOOH/Ca^(2+),we proposed the fluorescence emission mechanism of PDI-COOH/Ca^(2+)in THF/H_(2)O and THF,respectively.This work reveals a novel strategy of aggregated state fluorescence enhancement and reminds us of the important role of water in molecular fluorescence emission and assembly.展开更多
Pore structure engineering has been acknowledged as suitable approach to creating active sites and en-hancing ion transport capabilities of hard carbon anodes.However,conventional porous carbon materials exhibit high ...Pore structure engineering has been acknowledged as suitable approach to creating active sites and en-hancing ion transport capabilities of hard carbon anodes.However,conventional porous carbon materials exhibit high BET and surface defects.Additionally,the sodium storage mechanism predominantly occurs in the slope region.This contradicts practical application requirements because the capacity of the plateau region is crucial for determining the actual capacity of batteries.In our work,we prepared a novel“core-shell”carbon framework(CNA1200).Introducingclosedporesand carboxylgroupsinto coal-basedcarbon materials to enhance its sodium storage performance.The closed pore structure dominates in the“core”structure,which is attributed to the timely removal of sodium hydroxide(NaOH)to prevent further for-mation of active carbon structure.The presence of closed pores is beneficial for increasing sodium ion storage in the low-voltage plateau region.And the“shell”structure originates from coal tar pitch,it not only uniformly connects hard carbon particles together to improve cycling stability,but is also rich in carboxyl groups to enhance the reversible sodium storage performance in slope region.CNA1200 has ex-cellent electrochemical performance,it exhibits a specific capacity of 335.2 mAh g^(−1)at a current density of 20 mA g^(−1)with ICE=51.53%.In addition,CNA1200 has outstanding cycling stability with a capac-ity retention of 91.8%even when cycling over 200 times.When CNA1200 is used as anode paired with Na_(3)V_(2)(PO_(4))_(3)cathode,it demonstrates a capacity of 109.54 mAh g^(−1)at 0.1 C and capacity retention of 94.64%at 0.5 C.This work provides valuable methods for regulating the structure of sodium-ion battery(SIBs)anode and enhances the potential for commercialization.展开更多
Mitochondria and mitochondria-associated endoplasmic reticulum membrane in neurodegenerative diseases:Mitochondria generate most of the chemical energy needed to power the biochemical reactions of cells,and thus are o...Mitochondria and mitochondria-associated endoplasmic reticulum membrane in neurodegenerative diseases:Mitochondria generate most of the chemical energy needed to power the biochemical reactions of cells,and thus are often referred to as the"powerhouse"of the cell.Nevertheless,this organelle is also involved in a pleth,ora of different cellular functions such as calcium(Ca^(2+))homeostasis,apoptosis,oxidative stress,and several metabolic pathways including oxidative phosphorylation,tricarboxylic acid cycle,andβ-oxidation of fatty acids.展开更多
An efficient TfOH-catalyzed O—H insertion reaction of α-aryl diazoesters with carboxylic acids is reported.This metal-free protocol provides an operationally simple method for a one-pot assembly of diverse α-acylox...An efficient TfOH-catalyzed O—H insertion reaction of α-aryl diazoesters with carboxylic acids is reported.This metal-free protocol provides an operationally simple method for a one-pot assembly of diverse α-acyloxy esters in moderate to high yields with a broad substrate scope.All starting materials are readily available,and the reactions can be conducted in the open air at room temperature.展开更多
Four new coordination polymers,{[Cd(mbtx)(4OHphCOO)]NO_(3)}n(1),{[Zn(mbtx)(1,4-bdc)_(0.5)(H_(2)O)_(2)]·(1,4-bdc)_(0.5)·4H_(2)O}n(2),{[Cd2(mbtx)(5NO_(2)-bdc)_(2)(H_(2)O)_(3)]·4.5H_(2)O}n(3),and{[Zn(H_(2)...Four new coordination polymers,{[Cd(mbtx)(4OHphCOO)]NO_(3)}n(1),{[Zn(mbtx)(1,4-bdc)_(0.5)(H_(2)O)_(2)]·(1,4-bdc)_(0.5)·4H_(2)O}n(2),{[Cd2(mbtx)(5NO_(2)-bdc)_(2)(H_(2)O)_(3)]·4.5H_(2)O}n(3),and{[Zn(H_(2)O)6][Zn_(2)(mbtx)_(2)(btc)_(2)(H_(2)O)_(4)]·2H_(2)O}n(4)(mbtx=1,3-bis(4H-1,2,4-triazole)benzene,4OHphCOO-=p-hydroxybenzoate,1,4-bdc2-=1,4-benzenedicarboxylate,5NO_(2)-bdc2-=5-nitro-isophthalate,btc3-=1,3,5-benzenetricarboxylate),were synthesized under room temperature condition and characterized by single-crystal X-ray diffraction,elemental analyses,and powder X-ray diffraction.Single-crystal X-ray structural analysis shows that complexes 1 and 3 are 2D networks.In 1,the adjacent 2D networks are linked to a 3D network byπ-πstacking interaction.2 and 4 exhibit 1D chains,and the 1D chains are connected into a 3D network byπ-πstacking interaction and intermolecular hydrogen bond.Luminescence and thermogravimetric analysis of the four complexes were discussed.CCDC:2416406,1;2416407,2;2416408,3;2416409,4.展开更多
A strategy for copper-catalyzed and biphosphine ligand controlled boracarboxylation of 1,3-dienes and CO_(2) with 3,4-selectivity was developed.The Cu Cl coupled with DPPF(1,1-bis(diphenylphosphino)ferrocene)was assig...A strategy for copper-catalyzed and biphosphine ligand controlled boracarboxylation of 1,3-dienes and CO_(2) with 3,4-selectivity was developed.The Cu Cl coupled with DPPF(1,1-bis(diphenylphosphino)ferrocene)was assigned to be the best catalyst,with 84%yield and exclusive3,4-selectivity.The ligand effect on both catalytic activity and regioselectivity of boracarboxylation was disclosed,which is rarely reported in any copper catalyzed boracarboxylation.The borocupration process is revealed to be a vital step for the biphosphine participated boracarboxylation of 1,3-dienes with CO_(2).The minimal substrate distortion occurring in 3,4-borocupration favors the 3,4-regioselectivity of boracarboxylation.The“pocket”confinement and suitableβ_(n)(92°–106°)of bisphosphine ligands are demonstrated to be in favour of the interaction between LCu-Bpin complex(the catalytic precursor)and1,3-diene substrate to decrease their interaction energyΔE_(int)(ζ)in 3,4-borocupration,thus promoting the 3,4-boracarboxylation.展开更多
Microbial consortia that catalyze chain elongation processes have been enriched using different selection strategies,for which the electron donor is an essential one.Propanol is an extraordinarily promising electron d...Microbial consortia that catalyze chain elongation processes have been enriched using different selection strategies,for which the electron donor is an essential one.Propanol is an extraordinarily promising electron donor because it can be generated from renewable resources,including lignocellulosic biomass and protein wastes.Here,propanol was proven in detail to be an efficient electron donor,enhancing the production of odd medium-chain carboxylates during chain elongation.By exploring various electron acceptors,reactor conditions,and electron donor/electron acceptor mol ratios,our study highlights that acetate is the most suitable electron acceptor for the production of both odd-and even-chain carboxylates.The optimal conditions for propanol-based chain elongation were 30℃ and pH 6,achieving 82.8%selectivity for odd-chain carboxylates.Another critical insight from our work is that a propanol/acetate mol ratio of 1:1 can minimize the inhibitory effect of propanol and maximize the yield of medium-chain carboxylates,with the highest concentration of n-heptanoate reaching 124.5 mmol C/L.This was further illustrated by 16S rRNA amplicon sequencing,which elucidated that the community composition and keystone species in a propanol-based reactor closely resembled that of the ethanol one.The dominant phylum of the propanol-based reactor,Firmicutes showed a significant positive correlation with the concentrations of n-caproate and n-valerate.Additionally,the co-occurrence of Clostridium sensu stricto 12 and Oscillibacter,known as typical chain elongators,was identified within the propanol-based reactor.These findings enhance our understanding of propanolbased chain elongation,offer guiding principles for reactor microbiota assembly,and support efficient odd medium-chain carboxylate production.展开更多
Unconventional natural gas has become an important supplement to conventional energy sources,and the process of enrichment and purification of methane from low concentration coalbed methane is crucial.To this end,we r...Unconventional natural gas has become an important supplement to conventional energy sources,and the process of enrichment and purification of methane from low concentration coalbed methane is crucial.To this end,we report a copper-based metal-organic framework(MOF),ZJNU-119Cu,featuring two methane traps constructed with uncoordinated carboxylic acid oxygens and open metal sites.ZJNU-119Cu exhibits a high methane adsorption capacity(58.2 cm^(3)·g^(-1))at 298 K and 0.1 MPa and excellent CH_(4)/N_(2) separation performance under dynamic conditions.Densityfunctional theory calculations combined with grand canonical Monte Carlo simulation theory reveal the interaction mechanism for the uncoordinated carboxylic acid oxygen atoms and open metal sites in ZJNU-119Cu with CH4.The gas adsorption isotherms,heat of adsorption calculations,and breakthrough separation experiments indicate that this MOF is a very promising adsorbent for CH_(4)/N_(2) separation.展开更多
The photocatalytic reduction of CO_(2)is a crucial area of research aimed at addressing the dual challenges of mitigating rising CO_(2)emissions and producing sustainable chemical feedstocks.While multielectron reduct...The photocatalytic reduction of CO_(2)is a crucial area of research aimed at addressing the dual challenges of mitigating rising CO_(2)emissions and producing sustainable chemical feedstocks.While multielectron reduction pathways for CO_(2)are well explored,the single electron reduction to produce the highly reactive carbon dioxide radical anion(CO_(2)^(·-))remains challenging yet promising for green organic transformations.This review contributes to the field by providing a comprehensive analysis of the mechanisms,materials,and reaction pathways involved in CO_(2)^(·-)generation,focusing on the use of visible-lightdriven photocatalytic materials to circumvent the need for high-energy ultraviolet irradiation.Through a systematic examination of CO_(2)^(·-)production,detection methods,and chemical utilization in photocatalytic carboxylation reactions,this review advances understanding of the chemistry of CO_(2)^(·-)and its applications in sustainable chemical synthesis.In addition,it highlights existing key challenges,such as redox potential limitations,and proposes strategies for scaling up photocatalytic systems to enable practical application.By illuminating the pathway to effectively photocatalyze CO_(2)^(·-)generation and its transformative potential in sustainable chemical synthesis,this review equips scientists with critical insights and strategic approaches for overcoming current limitations,driving innovation in photocatalytic materials for solar-to-chemical energy conversion.展开更多
Solar-driven thermo-electric generation(STEG)emerges as a promising solution to mitigate the global en-ergy shortage.However,the practical application of conventional photothermal materials equipped with STEG is limit...Solar-driven thermo-electric generation(STEG)emerges as a promising solution to mitigate the global en-ergy shortage.However,the practical application of conventional photothermal materials equipped with STEG is limited due to low solar thermal conversion efficiency.Herein,we fabricated an epoxy resin(EP)nanocomposite,EP/CCA80,with excellent photo-thermal-electric conversion properties by embedding a vertically aligned aerogel consisting of cellulose nanofibers(CNF)and carboxylated multi-walled carbon nanotubes(CMWCNTs)into a transparent EP matrix.EP/CCA80 composites possessed a broad light ab-sorption range from 200 nm to 2500 nm and excellent photothermal properties.Under illumination of 1.0 kW m^(-2),EP/CCA80 achieved a notable stable temperature of 93.2℃ and a photothermal conversion efficiency of up to 54.35%with only 0.65 wt%CMWCNTs inclusion.Additionally,coupled with thermo-electric(TE)devices,the EP/CCA80 composite facilitated a significant temperature difference and voltage output of up to 25.3℃ and 160.29 mV(1.0 kW m^(-2)),respectively,which could power a small fan to rotate at a speed of 193 min^(-1).Such materials are poised to offer viable solutions for enhancing energy accessibility in remote regions,thereby contributing to the reduction of energy shortages and environ-mental degradation.展开更多
The detection of circulating tumor DNA(ctDNA)with high sensitivity and specificity is crucial for the early diagnosis and monitoring of tumors,as well as for drug therapy.In this study,a simple and highly sensitive bi...The detection of circulating tumor DNA(ctDNA)with high sensitivity and specificity is crucial for the early diagnosis and monitoring of tumors,as well as for drug therapy.In this study,a simple and highly sensitive biosensor was specifically designed for the identification of targeted ctDNA.For the first time,a three-dimensional polyvinylidene fluoride-graphene oxide-chitosan(PVDF/CS/GO)nanofiber mesh was fabricated on a polydimethylsiloxane(PDMS)micropillar substrate using electrospinning technology,and the nanofibers were functionalized with peptide nucleic acids probe-gold nanoparticle(PNA-AuNP)complexes,which served as affinity molecules for detecting the methylation of the E542K variant of the phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit α(PIK3CA)gene in the peripheral blood of cancer patients.Additionally,an anti-5-Methylcytosine monoclonal antibody-multi-walled carbon nanotubes-COOH complex(Anti-5-mC-MWCNTs-COOH)complex was incubated to result in significantly amplified electrochemical signals for the accurate quantification of the E542K variant of the PIK3CA gene.Detectable signal responses were observed only when both molecules were simultaneously present,greatly enhancing the accuracy of the analysis.The biosensor exhibits high capture sensitivity for the methylation level of the E542K variant of the PIK3CA gene across a concentration range of 50 to 10000 fmol/L,with the lowest detection limit of 10 fmol/L.The ctDNA nanobiosensor has been shown to be both feasible and valuable for quantifying ctDNA concentrations in clinical blood samples.Consequently,this 3D nanofiber biosensor shows significant potential for clinical applications in cancer diagnosis and personalized medical treatments.展开更多
The increase in anthropogenic carbon dioxide(CO_(2))emissions has exacerbated the deterioration of the global environment,which should be controlled to achieve carbon neutrality.Central to the core goal of achieving c...The increase in anthropogenic carbon dioxide(CO_(2))emissions has exacerbated the deterioration of the global environment,which should be controlled to achieve carbon neutrality.Central to the core goal of achieving carbon neutrality is the utilization of CO_(2) under economic and sustainable conditions.Recently,the strong need for carbon neutrality has led to a proliferation of studies on the direct conversion of CO_(2) into carboxylic acids,which can effectively alleviate CO_(2) emissions and create high-value chemicals.The purpose of this review is to present the application prospects of carboxylic acids and the basic principles of CO_(2) conversion into carboxylic acids through photo-,electric-,and thermal catalysis.Special attention is focused on the regulation strategy of the activity of abundant catalysts at the molecular level,inspiring the preparation of high-performance catalysts.In addition,theoretical calculations,advanced technologies,and numerous typical examples are introduced to elaborate on the corresponding process and influencing factors of catalytic activity.Finally,challenges and prospects are provided for the future development of this field.It is hoped that this review will contribute to a deeper understanding of the conversion of CO_(2) into carboxylic acids and inspire more innovative breakthroughs.展开更多
The pursuit of cleanliness,energy efficiency,and resource preservation through photochemical reactions has led to the emergence of novel pathways and methodologies in synthetic chemistry,rendering it one of the most d...The pursuit of cleanliness,energy efficiency,and resource preservation through photochemical reactions has led to the emergence of novel pathways and methodologies in synthetic chemistry,rendering it one of the most dynamic research domains within modern organic synthesis.Carbon dioxide(CO_(2)),owing to its non-toxic,cost-effective,abundant,and recyclable attributes,serves as an optimal C1 precursor in synthetic chemistry.Recent years have witnessed rapid advancements in the photochemical conversion of CO_(2) into carboxylic acid compounds,offering a gentle and highly efficient synthetic approach for their production.An overview of the research progress on the synthesis methodologies of carboxylic acid compounds through photochemical CO_(2) conversion is provided,while certain associated reaction mechanisms are also elucidated.展开更多
Utilizing CO_(2)for the production of bulky and valuable chemicals presents an attractive solution to address environmental and fossil energy crises.Among the various approaches,direct carboxylation of alcohols with C...Utilizing CO_(2)for the production of bulky and valuable chemicals presents an attractive solution to address environmental and fossil energy crises.Among the various approaches,direct carboxylation of alcohols with CO_(2)stands out as an eco-friendly process capable of efficiently producing carboxylic acids in a sustainable manner.However,the high dissociation energy of the C–O bond poses a significant challenge in this process.Over the past few decades,several strategies have been developed to activate alcohols and establish efficient catalytic systems for carboxylation with CO_(2).Nevertheless,the sporadic nature of reported approaches makes it difficult to determine the most effective one.This perspective aims to provide an overview of the current state-of-the-art catalytic protocols for carboxylating alcohols with CO_(2),encompassing esterification,halogenation,and photocatalysis,while considering their respective advantages and limitations.We aim to discern the most promising avenues for future development in this field.The insights presented in this perspective will contribute to the advancement of efficient and sustainable carboxylation methods using CO_(2),leading to the production of valuable chemicals in future.展开更多
Aqueous zinc metal batteries are regarded as the most promising energy storage system due to their advantages of high safety,low cost,and high theoretical capacity.However,the growth of dendrites and the occurrence of...Aqueous zinc metal batteries are regarded as the most promising energy storage system due to their advantages of high safety,low cost,and high theoretical capacity.However,the growth of dendrites and the occurrence of side reactions hinder the development of zinc metal batteries.Despite previous attempts to design advanced hydrogel electrolytes,achieving high mechanical performance and ionic conductivity of hydrogel electrolytes has remained challenging.In this work,a hydrogel electrolyte with an ionic crosslinked network is prepared by carboxylic bacterial cellulose fiber and imidazole-type ionic liquid,following by a covalent network of polyacrylamide.The hydrogel electrolyte possesses a superior ionic conductivity of 43.76 mS cm^(−1),leading to a Zn^(2+)migration number of 0.45,and high mechanical performance with an elastic modulus of 3.48 GPa and an elongation at breaking of 38.36%.More importantly,under the anion-coordination effect of the carboxyl group in bacterial cellulose and[BF4]−in imidazole-type ionic liquid,the solvation sheath of hydrated Zn^(2+)ions and the nucleation overpotential of Zn plating are regulated.The results of cycled testing show that the growth of zinc dendrites is effectively inhibited and the generation of irreversible by-products is reduced.With the carboxylic bacterial cellulose-based hydrogel electrolyte,the Zn||Zn symmetric batteries offer good cyclability as well as Zn||Ti batteries.展开更多
On the basis of coordinated electrodeposition of carboxylated chitosan(CCS),we presented a green method to prepare Cu NCs and Cu NCs/CCS nanocomposite films.The method shows a range of benefits,such as the convenient ...On the basis of coordinated electrodeposition of carboxylated chitosan(CCS),we presented a green method to prepare Cu NCs and Cu NCs/CCS nanocomposite films.The method shows a range of benefits,such as the convenient and eco-friendly process,mild conditions,and simple post-treatment.The experimental results reveal that a homogeneous deposited film(Cu NCs/CCS nanocomposite film)is generated on the Cu plate(the anode)after electrodeposition,which exhibits an obvious red florescence.The results from TEM observation suggest there are nanoparticles(with the average particle size of 2.3 nm)in the deposited film.Spectral analysis results both demonstrate the existence of Cu NCs in the deposited film.Moreover,the Cu NCs/CCS film modified electrode is directly created through electrodeposition of CCS,which enables promising application in the electrochemical sensing.By means of fluorescence properties of Cu NCs,the Cu NCs/CCS film also owns the potential in fluorescence detection.Therefore,this work builds a novel method for the green synthesis of Cu NCs,meanwhile it offers a convenient and new electrodeposition strategy to prepare polysaccharide-based Cu NCs nanocomposites for uses in functional nanocomposites and bioelectronic devices.展开更多
Easy hydrolysis in alkaline environments limits the use of polyimide fibers in environmental protection. The hydrolysis resistance levels of polyimide fibers can be improved by crosslinking of the macromolecular chain...Easy hydrolysis in alkaline environments limits the use of polyimide fibers in environmental protection. The hydrolysis resistance levels of polyimide fibers can be improved by crosslinking of the macromolecular chains. In this work, crosslinked polyimide fibers(CPI fibers) were produced by intrinsic carboxyl decarboxylation for the first time. The thermal stability of the polyimide fibers containing the intrinsic carboxyl groups(PIC fibers) was studied, and the temperature of the decarboxylation-crosslinking reaction was determined to be 450 ℃. The PIC fibers were hotdrawn to initiate thermal crosslinking of the carboxyl groups and molecular chain orientation at high temperature. The CPI fibers had high tensile strengths(0.72-1.46 GPa) and compressive strengths(401-604 MPa). The oriented macromolecules and chemically crosslinked structure improved the tightness of the molecular chains and endowed the CPI fibers with excellent hydrolytic resistance. The CPI-50 fiber did not dissolve in a 0.5 wt% NaOH solution during heating at 90 ℃ for 10 h, and the tensile strength retention reached 87% when treated in 0.5 wt% NaOH solutions at 90 ℃ for 1 h, providing a guarantee for its application in alkaline corrosive environments.展开更多
The carboxylation of readily available organo halides with CO_(2)represents a practical strategy to afford valuable carboxylic acids.However,efficient carboxylation of inexpensive unactivated alkyl chlorides is still ...The carboxylation of readily available organo halides with CO_(2)represents a practical strategy to afford valuable carboxylic acids.However,efficient carboxylation of inexpensive unactivated alkyl chlorides is still underdeveloped.Herein,we report the electro-reductive carboxylation of C–Cl bonds in unactivated chlorides and polyvinyl chloride with CO_(2).A variety of alkyl carboxylic acids are obtained in moderate to good yields under mild conditions with high chemoselectivity.Importantly,the utility of this electroreductive carboxylation is demonstrated with great potential in polyvinyl chloride(PVC)upgrading,which could convert discarded PVC from hydrophobic to hydrophilic functional products.Mechanistic experiments support the successive single electron reduction of unactivated chlorides to generate alkyl anion species and following nucleophilic attack on CO_(2)to give desired products.展开更多
A photoredox-catalyzed cascade carbon/carboxylation of activated alkenes with malonates acetals and CO_(2) has been achieved,leading to a range of functionalized 1,1,3-tricarboxylates in good efficiency under mild rea...A photoredox-catalyzed cascade carbon/carboxylation of activated alkenes with malonates acetals and CO_(2) has been achieved,leading to a range of functionalized 1,1,3-tricarboxylates in good efficiency under mild reaction conditions.This reaction provides a facile and sustainable method for the synthesis of tricarboxylates by using CO_(2) as the carboxylic source.展开更多
基金supported by the National Natural Science Foundation of China,Nos.91849115 and U1904207(to YX),81974211 and 82171247(to CS)Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences,No.2020-PT310-01(to YX).
文摘The E3 ubiquitin ligase,carboxyl terminus of heat shock protein 70(Hsp70)interacting protein(CHIP),also functions as a co-chaperone and plays a crucial role in the protein quality control system.In this study,we aimed to investigate the neuroprotective effect of overexpressed CHIP on Alzheimer’s disease.We used an adeno-associated virus vector that can cross the blood-brain barrier to mediate CHIP overexpression in APP/PS1 mouse brain.CHIP overexpression significantly ameliorated the performance of APP/PS1 mice in the Morris water maze and nest building tests,reduced amyloid-βplaques,and decreased the expression of both amyloid-βand phosphorylated tau.CHIP also alleviated the concentration of microglia and astrocytes around plaques.In APP/PS1 mice of a younger age,CHIP overexpression promoted an increase in ADAM10 expression and inhibitedβ-site APP cleaving enzyme 1,insulin degrading enzyme,and neprilysin expression.Levels of HSP70 and HSP40,which have functional relevance to CHIP,were also increased.Single nuclei transcriptome sequencing in the hippocampus of CHIP overexpressed mice showed that the lysosomal pathway and oligodendrocyte-related biological processes were up-regulated,which may also reflect a potential mechanism for the neuroprotective effect of CHIP.Our research shows that CHIP effectively reduces the behavior and pathological manifestations of APP/PS1 mice.Indeed,overexpression of CHIP could be a beneficial approach for the treatment of Alzheimer’s disease.
文摘Bay-site carboxyl functionalized perylene diimide derivative 1,7-COOH-PDI-C_(12)(PDI-COOH)was synthesized and distinct enhanced fluorescence was observed through combining with calcium ion(Ca^(2+))in THF/H_(2)O solution.The assembly and fluorescence behavior of PDI-COOH/Ca^(2+)were studied in detail by changing hydration state with different concentrations.Based on the differences in assembly morphology and stoichiometric ratios of PDICOOH/Ca^(2+),we proposed the fluorescence emission mechanism of PDI-COOH/Ca^(2+)in THF/H_(2)O and THF,respectively.This work reveals a novel strategy of aggregated state fluorescence enhancement and reminds us of the important role of water in molecular fluorescence emission and assembly.
基金the National Natural Science Foundation of China(No.21978164,22078189 and 22105120)the Outstanding Youth Science Fund of Shaanxi Province(No.2021JC-046)and the Special Support Program for high level talents of Shaanxi Province+3 种基金the Innovation Support Program of Shaanxi Province(2021JZY-001)the Key Research and Development Program of Shaanxi Province(No.2020GY-243)the Special Research Fund of Education Department of Shaanxi(No.20JK0535)the National High-end Foreign Expert Project(No.GDW20186100428).
文摘Pore structure engineering has been acknowledged as suitable approach to creating active sites and en-hancing ion transport capabilities of hard carbon anodes.However,conventional porous carbon materials exhibit high BET and surface defects.Additionally,the sodium storage mechanism predominantly occurs in the slope region.This contradicts practical application requirements because the capacity of the plateau region is crucial for determining the actual capacity of batteries.In our work,we prepared a novel“core-shell”carbon framework(CNA1200).Introducingclosedporesand carboxylgroupsinto coal-basedcarbon materials to enhance its sodium storage performance.The closed pore structure dominates in the“core”structure,which is attributed to the timely removal of sodium hydroxide(NaOH)to prevent further for-mation of active carbon structure.The presence of closed pores is beneficial for increasing sodium ion storage in the low-voltage plateau region.And the“shell”structure originates from coal tar pitch,it not only uniformly connects hard carbon particles together to improve cycling stability,but is also rich in carboxyl groups to enhance the reversible sodium storage performance in slope region.CNA1200 has ex-cellent electrochemical performance,it exhibits a specific capacity of 335.2 mAh g^(−1)at a current density of 20 mA g^(−1)with ICE=51.53%.In addition,CNA1200 has outstanding cycling stability with a capac-ity retention of 91.8%even when cycling over 200 times.When CNA1200 is used as anode paired with Na_(3)V_(2)(PO_(4))_(3)cathode,it demonstrates a capacity of 109.54 mAh g^(−1)at 0.1 C and capacity retention of 94.64%at 0.5 C.This work provides valuable methods for regulating the structure of sodium-ion battery(SIBs)anode and enhances the potential for commercialization.
基金supported by LifeArc Philanthropic Fund(P2019-0004)LifeArc Pathfinder Award+7 种基金along with Wellcome Trust Seed Award(109626/Z/15/Z)FA PESP-UoB Strategic Collaboration FundBirmingham Fellowship(to SS)grants from Laboratoire d'Excellence Revive(Investissement d'AvenirANR-10-LABX-73)the Region lle-de-France via doctoral school Innovation Therapeutique,du Fondamentalàl'Appliqué(ED569)from Universite Paris-Saclay(to LA)Medical Research Council(MRC)Developmental Pathway Funding Scheme(DPFS)grant(MR/P007732/1)(to TB)supported by the Association Fran?aise contre les Myopathies(AFM-Téléthon)。
文摘Mitochondria and mitochondria-associated endoplasmic reticulum membrane in neurodegenerative diseases:Mitochondria generate most of the chemical energy needed to power the biochemical reactions of cells,and thus are often referred to as the"powerhouse"of the cell.Nevertheless,this organelle is also involved in a pleth,ora of different cellular functions such as calcium(Ca^(2+))homeostasis,apoptosis,oxidative stress,and several metabolic pathways including oxidative phosphorylation,tricarboxylic acid cycle,andβ-oxidation of fatty acids.
文摘An efficient TfOH-catalyzed O—H insertion reaction of α-aryl diazoesters with carboxylic acids is reported.This metal-free protocol provides an operationally simple method for a one-pot assembly of diverse α-acyloxy esters in moderate to high yields with a broad substrate scope.All starting materials are readily available,and the reactions can be conducted in the open air at room temperature.
文摘Four new coordination polymers,{[Cd(mbtx)(4OHphCOO)]NO_(3)}n(1),{[Zn(mbtx)(1,4-bdc)_(0.5)(H_(2)O)_(2)]·(1,4-bdc)_(0.5)·4H_(2)O}n(2),{[Cd2(mbtx)(5NO_(2)-bdc)_(2)(H_(2)O)_(3)]·4.5H_(2)O}n(3),and{[Zn(H_(2)O)6][Zn_(2)(mbtx)_(2)(btc)_(2)(H_(2)O)_(4)]·2H_(2)O}n(4)(mbtx=1,3-bis(4H-1,2,4-triazole)benzene,4OHphCOO-=p-hydroxybenzoate,1,4-bdc2-=1,4-benzenedicarboxylate,5NO_(2)-bdc2-=5-nitro-isophthalate,btc3-=1,3,5-benzenetricarboxylate),were synthesized under room temperature condition and characterized by single-crystal X-ray diffraction,elemental analyses,and powder X-ray diffraction.Single-crystal X-ray structural analysis shows that complexes 1 and 3 are 2D networks.In 1,the adjacent 2D networks are linked to a 3D network byπ-πstacking interaction.2 and 4 exhibit 1D chains,and the 1D chains are connected into a 3D network byπ-πstacking interaction and intermolecular hydrogen bond.Luminescence and thermogravimetric analysis of the four complexes were discussed.CCDC:2416406,1;2416407,2;2416408,3;2416409,4.
基金the National Key R&D Program of China(No.2022YFB4101900)National Natural Science Foundation of China(Nos.22278305,U21B2096)Natural Science Foundation of Tianjin City(No.23JCZDJC00040)。
文摘A strategy for copper-catalyzed and biphosphine ligand controlled boracarboxylation of 1,3-dienes and CO_(2) with 3,4-selectivity was developed.The Cu Cl coupled with DPPF(1,1-bis(diphenylphosphino)ferrocene)was assigned to be the best catalyst,with 84%yield and exclusive3,4-selectivity.The ligand effect on both catalytic activity and regioselectivity of boracarboxylation was disclosed,which is rarely reported in any copper catalyzed boracarboxylation.The borocupration process is revealed to be a vital step for the biphosphine participated boracarboxylation of 1,3-dienes with CO_(2).The minimal substrate distortion occurring in 3,4-borocupration favors the 3,4-regioselectivity of boracarboxylation.The“pocket”confinement and suitableβ_(n)(92°–106°)of bisphosphine ligands are demonstrated to be in favour of the interaction between LCu-Bpin complex(the catalytic precursor)and1,3-diene substrate to decrease their interaction energyΔE_(int)(ζ)in 3,4-borocupration,thus promoting the 3,4-boracarboxylation.
基金supported by the National Key R&D Program of China(No.2022YFC2105301)the National Natural Science Foundation of China(No.52270096).
文摘Microbial consortia that catalyze chain elongation processes have been enriched using different selection strategies,for which the electron donor is an essential one.Propanol is an extraordinarily promising electron donor because it can be generated from renewable resources,including lignocellulosic biomass and protein wastes.Here,propanol was proven in detail to be an efficient electron donor,enhancing the production of odd medium-chain carboxylates during chain elongation.By exploring various electron acceptors,reactor conditions,and electron donor/electron acceptor mol ratios,our study highlights that acetate is the most suitable electron acceptor for the production of both odd-and even-chain carboxylates.The optimal conditions for propanol-based chain elongation were 30℃ and pH 6,achieving 82.8%selectivity for odd-chain carboxylates.Another critical insight from our work is that a propanol/acetate mol ratio of 1:1 can minimize the inhibitory effect of propanol and maximize the yield of medium-chain carboxylates,with the highest concentration of n-heptanoate reaching 124.5 mmol C/L.This was further illustrated by 16S rRNA amplicon sequencing,which elucidated that the community composition and keystone species in a propanol-based reactor closely resembled that of the ethanol one.The dominant phylum of the propanol-based reactor,Firmicutes showed a significant positive correlation with the concentrations of n-caproate and n-valerate.Additionally,the co-occurrence of Clostridium sensu stricto 12 and Oscillibacter,known as typical chain elongators,was identified within the propanol-based reactor.These findings enhance our understanding of propanolbased chain elongation,offer guiding principles for reactor microbiota assembly,and support efficient odd medium-chain carboxylate production.
基金financial support from the National Natural Science Foundation of China(22408258 and 22378287)the Joint Founds of the National Natural Science Foundation of China(U20B6004)the Natural Science Foundation of Shanxi Province(202303021222012).
文摘Unconventional natural gas has become an important supplement to conventional energy sources,and the process of enrichment and purification of methane from low concentration coalbed methane is crucial.To this end,we report a copper-based metal-organic framework(MOF),ZJNU-119Cu,featuring two methane traps constructed with uncoordinated carboxylic acid oxygens and open metal sites.ZJNU-119Cu exhibits a high methane adsorption capacity(58.2 cm^(3)·g^(-1))at 298 K and 0.1 MPa and excellent CH_(4)/N_(2) separation performance under dynamic conditions.Densityfunctional theory calculations combined with grand canonical Monte Carlo simulation theory reveal the interaction mechanism for the uncoordinated carboxylic acid oxygen atoms and open metal sites in ZJNU-119Cu with CH4.The gas adsorption isotherms,heat of adsorption calculations,and breakthrough separation experiments indicate that this MOF is a very promising adsorbent for CH_(4)/N_(2) separation.
基金funding programs,the Walter Benjamin Programme(DFG,German Research Foundation,project number:530742479)the ProChancecareer Programme for the Promotion of Equal Opportunities in Academia for providing the financial support+1 种基金financial support by the Deutsche Forschungsgemeinschaft via the TRR 234 Cata Light(DFG,German Research Foundation)-Projektnummer 364549901-TRR 234[B6]the financial support taken from the CSIR and UGC,Delhi,India。
文摘The photocatalytic reduction of CO_(2)is a crucial area of research aimed at addressing the dual challenges of mitigating rising CO_(2)emissions and producing sustainable chemical feedstocks.While multielectron reduction pathways for CO_(2)are well explored,the single electron reduction to produce the highly reactive carbon dioxide radical anion(CO_(2)^(·-))remains challenging yet promising for green organic transformations.This review contributes to the field by providing a comprehensive analysis of the mechanisms,materials,and reaction pathways involved in CO_(2)^(·-)generation,focusing on the use of visible-lightdriven photocatalytic materials to circumvent the need for high-energy ultraviolet irradiation.Through a systematic examination of CO_(2)^(·-)production,detection methods,and chemical utilization in photocatalytic carboxylation reactions,this review advances understanding of the chemistry of CO_(2)^(·-)and its applications in sustainable chemical synthesis.In addition,it highlights existing key challenges,such as redox potential limitations,and proposes strategies for scaling up photocatalytic systems to enable practical application.By illuminating the pathway to effectively photocatalyze CO_(2)^(·-)generation and its transformative potential in sustainable chemical synthesis,this review equips scientists with critical insights and strategic approaches for overcoming current limitations,driving innovation in photocatalytic materials for solar-to-chemical energy conversion.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.52073043 and 52173069)the Fundamental Research Funds for the Central Universities(Grant No.2572022CG03)+1 种基金the Key Research and Development Projects in Heilongjiang Province(Grant No.GZ20210089)the Australian Research Council(Grant Nos.LP220100278,DP240102628,and DP240102728).
文摘Solar-driven thermo-electric generation(STEG)emerges as a promising solution to mitigate the global en-ergy shortage.However,the practical application of conventional photothermal materials equipped with STEG is limited due to low solar thermal conversion efficiency.Herein,we fabricated an epoxy resin(EP)nanocomposite,EP/CCA80,with excellent photo-thermal-electric conversion properties by embedding a vertically aligned aerogel consisting of cellulose nanofibers(CNF)and carboxylated multi-walled carbon nanotubes(CMWCNTs)into a transparent EP matrix.EP/CCA80 composites possessed a broad light ab-sorption range from 200 nm to 2500 nm and excellent photothermal properties.Under illumination of 1.0 kW m^(-2),EP/CCA80 achieved a notable stable temperature of 93.2℃ and a photothermal conversion efficiency of up to 54.35%with only 0.65 wt%CMWCNTs inclusion.Additionally,coupled with thermo-electric(TE)devices,the EP/CCA80 composite facilitated a significant temperature difference and voltage output of up to 25.3℃ and 160.29 mV(1.0 kW m^(-2)),respectively,which could power a small fan to rotate at a speed of 193 min^(-1).Such materials are poised to offer viable solutions for enhancing energy accessibility in remote regions,thereby contributing to the reduction of energy shortages and environ-mental degradation.
基金Funded by the National Natural Science Foundation of China(No.11804121)Special Funds for Central Guiding Local Scientific and Technological Development Project(No.2016ZYYD049)。
文摘The detection of circulating tumor DNA(ctDNA)with high sensitivity and specificity is crucial for the early diagnosis and monitoring of tumors,as well as for drug therapy.In this study,a simple and highly sensitive biosensor was specifically designed for the identification of targeted ctDNA.For the first time,a three-dimensional polyvinylidene fluoride-graphene oxide-chitosan(PVDF/CS/GO)nanofiber mesh was fabricated on a polydimethylsiloxane(PDMS)micropillar substrate using electrospinning technology,and the nanofibers were functionalized with peptide nucleic acids probe-gold nanoparticle(PNA-AuNP)complexes,which served as affinity molecules for detecting the methylation of the E542K variant of the phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit α(PIK3CA)gene in the peripheral blood of cancer patients.Additionally,an anti-5-Methylcytosine monoclonal antibody-multi-walled carbon nanotubes-COOH complex(Anti-5-mC-MWCNTs-COOH)complex was incubated to result in significantly amplified electrochemical signals for the accurate quantification of the E542K variant of the PIK3CA gene.Detectable signal responses were observed only when both molecules were simultaneously present,greatly enhancing the accuracy of the analysis.The biosensor exhibits high capture sensitivity for the methylation level of the E542K variant of the PIK3CA gene across a concentration range of 50 to 10000 fmol/L,with the lowest detection limit of 10 fmol/L.The ctDNA nanobiosensor has been shown to be both feasible and valuable for quantifying ctDNA concentrations in clinical blood samples.Consequently,this 3D nanofiber biosensor shows significant potential for clinical applications in cancer diagnosis and personalized medical treatments.
基金financial support from the King Abdullah University of Science and Technology(KAUST).
文摘The increase in anthropogenic carbon dioxide(CO_(2))emissions has exacerbated the deterioration of the global environment,which should be controlled to achieve carbon neutrality.Central to the core goal of achieving carbon neutrality is the utilization of CO_(2) under economic and sustainable conditions.Recently,the strong need for carbon neutrality has led to a proliferation of studies on the direct conversion of CO_(2) into carboxylic acids,which can effectively alleviate CO_(2) emissions and create high-value chemicals.The purpose of this review is to present the application prospects of carboxylic acids and the basic principles of CO_(2) conversion into carboxylic acids through photo-,electric-,and thermal catalysis.Special attention is focused on the regulation strategy of the activity of abundant catalysts at the molecular level,inspiring the preparation of high-performance catalysts.In addition,theoretical calculations,advanced technologies,and numerous typical examples are introduced to elaborate on the corresponding process and influencing factors of catalytic activity.Finally,challenges and prospects are provided for the future development of this field.It is hoped that this review will contribute to a deeper understanding of the conversion of CO_(2) into carboxylic acids and inspire more innovative breakthroughs.
文摘The pursuit of cleanliness,energy efficiency,and resource preservation through photochemical reactions has led to the emergence of novel pathways and methodologies in synthetic chemistry,rendering it one of the most dynamic research domains within modern organic synthesis.Carbon dioxide(CO_(2)),owing to its non-toxic,cost-effective,abundant,and recyclable attributes,serves as an optimal C1 precursor in synthetic chemistry.Recent years have witnessed rapid advancements in the photochemical conversion of CO_(2) into carboxylic acid compounds,offering a gentle and highly efficient synthetic approach for their production.An overview of the research progress on the synthesis methodologies of carboxylic acid compounds through photochemical CO_(2) conversion is provided,while certain associated reaction mechanisms are also elucidated.
基金Financial support from the National Natural Science Foundation of China(No.22271060)the Department of Chemistry at Fudan UniversityNanjing Forestry University。
文摘Utilizing CO_(2)for the production of bulky and valuable chemicals presents an attractive solution to address environmental and fossil energy crises.Among the various approaches,direct carboxylation of alcohols with CO_(2)stands out as an eco-friendly process capable of efficiently producing carboxylic acids in a sustainable manner.However,the high dissociation energy of the C–O bond poses a significant challenge in this process.Over the past few decades,several strategies have been developed to activate alcohols and establish efficient catalytic systems for carboxylation with CO_(2).Nevertheless,the sporadic nature of reported approaches makes it difficult to determine the most effective one.This perspective aims to provide an overview of the current state-of-the-art catalytic protocols for carboxylating alcohols with CO_(2),encompassing esterification,halogenation,and photocatalysis,while considering their respective advantages and limitations.We aim to discern the most promising avenues for future development in this field.The insights presented in this perspective will contribute to the advancement of efficient and sustainable carboxylation methods using CO_(2),leading to the production of valuable chemicals in future.
基金National Natural Science Foundation of China(51903113,51763014,and 52073133)China Postdoctoral Science Foundation(2022T150282,2019M663858)Program for Hongliu Excellent and Distinguished Young Scholars at Lanzhou University of Technology.
文摘Aqueous zinc metal batteries are regarded as the most promising energy storage system due to their advantages of high safety,low cost,and high theoretical capacity.However,the growth of dendrites and the occurrence of side reactions hinder the development of zinc metal batteries.Despite previous attempts to design advanced hydrogel electrolytes,achieving high mechanical performance and ionic conductivity of hydrogel electrolytes has remained challenging.In this work,a hydrogel electrolyte with an ionic crosslinked network is prepared by carboxylic bacterial cellulose fiber and imidazole-type ionic liquid,following by a covalent network of polyacrylamide.The hydrogel electrolyte possesses a superior ionic conductivity of 43.76 mS cm^(−1),leading to a Zn^(2+)migration number of 0.45,and high mechanical performance with an elastic modulus of 3.48 GPa and an elongation at breaking of 38.36%.More importantly,under the anion-coordination effect of the carboxyl group in bacterial cellulose and[BF4]−in imidazole-type ionic liquid,the solvation sheath of hydrated Zn^(2+)ions and the nucleation overpotential of Zn plating are regulated.The results of cycled testing show that the growth of zinc dendrites is effectively inhibited and the generation of irreversible by-products is reduced.With the carboxylic bacterial cellulose-based hydrogel electrolyte,the Zn||Zn symmetric batteries offer good cyclability as well as Zn||Ti batteries.
基金Funded by the National Natural Science Foundation of China(No.51873167)the Fundamental Research Funds for the Central Universities(WUT:2022-CL-A1-04)。
文摘On the basis of coordinated electrodeposition of carboxylated chitosan(CCS),we presented a green method to prepare Cu NCs and Cu NCs/CCS nanocomposite films.The method shows a range of benefits,such as the convenient and eco-friendly process,mild conditions,and simple post-treatment.The experimental results reveal that a homogeneous deposited film(Cu NCs/CCS nanocomposite film)is generated on the Cu plate(the anode)after electrodeposition,which exhibits an obvious red florescence.The results from TEM observation suggest there are nanoparticles(with the average particle size of 2.3 nm)in the deposited film.Spectral analysis results both demonstrate the existence of Cu NCs in the deposited film.Moreover,the Cu NCs/CCS film modified electrode is directly created through electrodeposition of CCS,which enables promising application in the electrochemical sensing.By means of fluorescence properties of Cu NCs,the Cu NCs/CCS film also owns the potential in fluorescence detection.Therefore,this work builds a novel method for the green synthesis of Cu NCs,meanwhile it offers a convenient and new electrodeposition strategy to prepare polysaccharide-based Cu NCs nanocomposites for uses in functional nanocomposites and bioelectronic devices.
基金financially supported by the Scientific Research Innovation Plan of Shanghai Education Commission (No. 2019-01-07-00-03-E00001)the National Natural Science Foundation of China (Nos. U21A2087 and 21975040)the Natural Science Foundation of Shanghai (No. 21ZR1400200)。
文摘Easy hydrolysis in alkaline environments limits the use of polyimide fibers in environmental protection. The hydrolysis resistance levels of polyimide fibers can be improved by crosslinking of the macromolecular chains. In this work, crosslinked polyimide fibers(CPI fibers) were produced by intrinsic carboxyl decarboxylation for the first time. The thermal stability of the polyimide fibers containing the intrinsic carboxyl groups(PIC fibers) was studied, and the temperature of the decarboxylation-crosslinking reaction was determined to be 450 ℃. The PIC fibers were hotdrawn to initiate thermal crosslinking of the carboxyl groups and molecular chain orientation at high temperature. The CPI fibers had high tensile strengths(0.72-1.46 GPa) and compressive strengths(401-604 MPa). The oriented macromolecules and chemically crosslinked structure improved the tightness of the molecular chains and endowed the CPI fibers with excellent hydrolytic resistance. The CPI-50 fiber did not dissolve in a 0.5 wt% NaOH solution during heating at 90 ℃ for 10 h, and the tensile strength retention reached 87% when treated in 0.5 wt% NaOH solutions at 90 ℃ for 1 h, providing a guarantee for its application in alkaline corrosive environments.
基金provided by the National Natural Science Foundation of China(Nos.22225106,22201027)Fundamental Research Funds for the Central Universities。
文摘The carboxylation of readily available organo halides with CO_(2)represents a practical strategy to afford valuable carboxylic acids.However,efficient carboxylation of inexpensive unactivated alkyl chlorides is still underdeveloped.Herein,we report the electro-reductive carboxylation of C–Cl bonds in unactivated chlorides and polyvinyl chloride with CO_(2).A variety of alkyl carboxylic acids are obtained in moderate to good yields under mild conditions with high chemoselectivity.Importantly,the utility of this electroreductive carboxylation is demonstrated with great potential in polyvinyl chloride(PVC)upgrading,which could convert discarded PVC from hydrophobic to hydrophilic functional products.Mechanistic experiments support the successive single electron reduction of unactivated chlorides to generate alkyl anion species and following nucleophilic attack on CO_(2)to give desired products.
文摘A photoredox-catalyzed cascade carbon/carboxylation of activated alkenes with malonates acetals and CO_(2) has been achieved,leading to a range of functionalized 1,1,3-tricarboxylates in good efficiency under mild reaction conditions.This reaction provides a facile and sustainable method for the synthesis of tricarboxylates by using CO_(2) as the carboxylic source.
