Typical feed gas mixtures used in technological and other plasmas may give rise to reaction networks involving several hundred reactions.Such chemistries are often too large to be used in full reactor simulations and ...Typical feed gas mixtures used in technological and other plasmas may give rise to reaction networks involving several hundred reactions.Such chemistries are often too large to be used in full reactor simulations and it is therefore desirable to construct reduced chemistry networks which mimic as closely as possible the behavior of the full chemistry but employ far fewer individual reactions and species.Constructed chemistries are available from the Quantemol database (QDB) and two approaches to constructing reduced chemistry from these chemistries based on (a) physical intuition and (b) sensitivity analysis of dominant reaction pathways,are explored.In doing this it is necessary to consider different pressure and power regimes.Reduced chemistry sets are presented for CF4/O2/N2/H2,for which 396 reactions and 52 species are reduced to 71 reactions and 26 species,and for pure O2,for which 45 reactions and 10 species are reduced to 34 reactions.展开更多
BACKGROUND Coronavirus disease(COVID-19)patients exhibit different patterns of liver impairment,according to growing evidence.AIM In this study,we sought to provide a comprehensive analysis of liver test parameters in...BACKGROUND Coronavirus disease(COVID-19)patients exhibit different patterns of liver impairment,according to growing evidence.AIM In this study,we sought to provide a comprehensive analysis of liver test parameters in patients with severe and non-severe COVID-19.METHODS We performed a meta-analysis of published liver manifestations and described the liver damage in COVID-19.We searched PubMed,Google Scholar,Embase,Cochrane Library,medRxiv,bioRxiv,and three Chinese electronic databases through April 18,2020,in accordance with the Preferred Reporting Items for Meta-Analyses.We analyzed pooled data on liver chemistries stratified by COVID-19 severity using a fixed or random-effects model.RESULTS A meta-analysis of 56 studies,including 11052 patients,found that the pooled mean alanine aminotransferase(ALT)in severe COVID-19 cases was 35.9 IU/L whereas in non-severe COVID-19 cases was 27.3 IU/L.Average aspa-rtate aminotransferase(AST)levels were 44.3 IU/L in severe cases compared to 27.9 IU/L in non-severe cases.In addition,AST levels are often higher than ALT levels regardless of disease severity.The severe cases tended to have a higher gammaglutamyltransferase level but a lower albumin level than the non-severe cases.CONCLUSION Severe COVID-19 was more likely to be associated with abnormal liver test results.Monitoring liver chemistry closely can help detect disease progression early.展开更多
Silica rods with homogeneous(hydrophilic or hydrophobic)and amphiphilic surface properties were synthesized and their efficiencies in suppressing the flow-induced droplet coalescence of immiscible polyisobutylene(PIB)...Silica rods with homogeneous(hydrophilic or hydrophobic)and amphiphilic surface properties were synthesized and their efficiencies in suppressing the flow-induced droplet coalescence of immiscible polyisobutylene(PIB)/polydimethylsiloxane(PDMS)blends were evaluated via in situ visualization technique.The flow-induced coalescence behavior of blends was found to strongly depend on the surface nature and concentration of silica rods added as well as the blend ratio.While a trace amount of rods promoted coalescence,all kinds of rods demonstrated a morphology refinement effect at high rod concentrations.Good compatibilization effects were obtained at high rod concentrations,especially for hydrophilic and amphiphilic rods.Based on confocal laser scanning microscopy results,these phenomena observed were interpreted reasonably in terms of the selective distribution and aggregation of silica rods,which were suggested to be decisive for the stabilization mechanism and efficiency of these rods.展开更多
Recently,the focus of materials research has shifted toward intelligent materials and structures with customizable properties and stimulus-responsive functions.Here,a recyclable thermosetting epoxy resin with self-rep...Recently,the focus of materials research has shifted toward intelligent materials and structures with customizable properties and stimulus-responsive functions.Here,a recyclable thermosetting epoxy resin with self-reported wear and customizable friction is achieved through dynamic and reversible molecular structure design.The epoxy vitrimer displays exceptional mechanical properties,with a Young's modulus of 2.3 GPa,elongation at break of 7.1%,and tensile strength of 79.25 MPa.Based on the reversible exchange of dynamic covalent bonds,the epoxy vitrimer can be fully recovered through hot pressing without the need for additional adhesives or catalysts,and even self-healing can be achieved.Furthermore,by utilizing the reversibility of dynamic covalent bonds,nanofillers(graphene oxide(GO)and polytetrafluoroethylene(PTFE))with specific tribological properties are incorporated into the recovery process to achieve customizable friction coefficients and wear rates.The self-reported characteristics of wear based on sulfur radicals are realized by exploiting the dynamic nature of disulfide bonds.The correlation between wear time and wear state is investigated.The molecular structure design of epoxy based on dynamic covalent bonds has resulted in a versatile thermosetting material with self-reporting and customizable friction properties that is ideal for sustainable engineering and friction applications.This enables intelligent manufacturing while reducing resource waste.展开更多
Recycling and second life of lithium-ion batteries are vital for lowering the growing resource demand of sectors like mobility or home energy storage.However,an often-overlooked issue is the sometimes-unknown cell che...Recycling and second life of lithium-ion batteries are vital for lowering the growing resource demand of sectors like mobility or home energy storage.However,an often-overlooked issue is the sometimes-unknown cell chemistry of batteries entering the end-of-life.In this work,a machine learning based approach for the identi-fication of lithium-ion battery cathode chemistries is presented.First,an initial measurement boundary deter-mination is introduced.Using the Python Battery Mathematical Modelling(PyBaMM)framework,synthetical partial open circuit voltage(OCV)charge and discharge curves are generated with an electrochemical single particle model for three different cathode chemistries and the initial state of charge and state of health values as well as the initial capacities are varied.The dV/dQ characteristics are chosen as features and four machine learning algorithms are trained on different lengths of OCV curves.The trade-off between achievable accuracy and the number of OCV steps showed that an increasing accuracy correlates with a higher step number.While extremely small charge and discharge capacities per step did not yield sufficient testing accuracies,capacities starting from 0.2 Ah per step up to 0.6 Ah per step showed increasingly good results with an accuracy of up to 89.3%for 0.5 Ah and 15 OCV steps.Additionally,the approach was validated by classifying experimental data.The results especially demonstrate the effectiveness of the approach to distinguish between lithium iron phos-phate(LFP)and lithium nickel manganese cobalt(NMC)cells.展开更多
Food Science and Human Wellness(FSHW ISSN:2213-4530,CN 10-1750/TS)publishes original research papers demonstrating the latest advancement of multidisci-plinary subjects related to food science and human health..Topics...Food Science and Human Wellness(FSHW ISSN:2213-4530,CN 10-1750/TS)publishes original research papers demonstrating the latest advancement of multidisci-plinary subjects related to food science and human health..Topics may include but not limited to:nutriology,bio-chemistry,microbiology,immunology and toxicology.展开更多
Biomass-based hydrocarbon fuels,as one of the alternatives to traditional fossil fuels,have attracted considerable attention in the energy field due to their renewability and environmental benefits.This article provid...Biomass-based hydrocarbon fuels,as one of the alternatives to traditional fossil fuels,have attracted considerable attention in the energy field due to their renewability and environmental benefits.This article provides a systematic review of recent research progress in the chemical synthesis of biomass-based hydrocarbon fuels.It outlines the conversion pathways using feedstocks such as lipids,terpenoids,cellulose/hemicellulose,and lignin.Depending on the feedstock,various products with distinct structural characteristics can be prepared through reactions such as cyclization,condensation,and catalytic hydrogenation.Throughout the synthesis process,three key factors play a critical role:efficient catalyst development,production process optimization,and computational-chemistry-based molecular design.Finally,the article discusses future perspectives for biomass-based hydrocarbon fuel synthesis research.展开更多
The complexes 1-4 of cyclobutanocucurbit[5]uril(CyB5Q[5])with Na^(+)/K^(+)have been synthesized and characterized by single-crystal X-ray diffraction.The results show that although the inorganic salts are used when th...The complexes 1-4 of cyclobutanocucurbit[5]uril(CyB5Q[5])with Na^(+)/K^(+)have been synthesized and characterized by single-crystal X-ray diffraction.The results show that although the inorganic salts are used when the cations are the same and the anions are different,in complex 1,Na^(+)closes one port of CyB5Q[5]through Na—O seven coordination bonds to form a molecular bowl;in complex 3,Na^(+)completely closes the two ports of CyB5Q[5]to form a molecular capsule with six Na—O coordination bonds;in complexes 2 and 4,the two ports of CyB5Q[5]are completely closed to form K—O coordinated molecular capsules,but the K^(+)of complex 2 is six-coordinated and that of complex 4 is eight-/nine-coordinated.and complex 4 are connected by three oxygen bridges to form a 1D molecular chain.CCDC:2457122,1;2457121,2;2457400,3;2457120,4.展开更多
Chinese Chemical Letters(CCL)(ISSN 1001-8417)was founded in July 1990.The journal publishes preliminary accounts in the whole field of chemistry,including inorganic chemistry,organic chemistry,analytical chemistry,phy...Chinese Chemical Letters(CCL)(ISSN 1001-8417)was founded in July 1990.The journal publishes preliminary accounts in the whole field of chemistry,including inorganic chemistry,organic chemistry,analytical chemistry,physical chemistry,polymer chemistry,applied chemistry,etc.,satisfying a real and urgent need for the dissemination of research results,especially hot topics.The journal does not accept articles previously published or scheduled to be published.To verify originality,your article may be checked by the originality detection service Cross Check.展开更多
The deuterium labeling has garnered significant interest in drug discovery due to its critical role on improving pharmacokinetic and metabolic properties.However,despite its pharmaceutical value,the general and rapid ...The deuterium labeling has garnered significant interest in drug discovery due to its critical role on improving pharmacokinetic and metabolic properties.However,despite its pharmaceutical value,the general and rapid syntheses of aromatic scaffolds that contains deuterium remain an important yet elusive task.State-of-the-art approaches mainly relied on the transition metal-catalyzed C-H deuteration via the assistance of directing groups(DGs),which often suffered from over-deuteration and lengthy step counts required for installation and/or removal of DG.Herein,we report a generalizable synthetic linchpin strategy for the facile preparation of the ortho-deuterated aromatic core.Through capture of aryne-derived 1,3-zwitterion with heavy water,we synthesized an array of ortho-deuterated aryl sulfonium salts.These novel linchpins not only participated the transition metal catalyzed cross-coupling reaction as nucleophiles,but also served as aryl radical reservoirs under photochemical or electrochemical conditions,enabling facile and precise access to structurally diverse deuterated aromatics.Moreover,we have disclosed a novel EDA complex enabled direct arylation of phosphines under visible-light irradiation,further expanding the utility of our platform approach.展开更多
Interlocked covalent organic cages have aesthetic skeletons endowed with structural and topological complexity.Their self-assembly provides a unique possibility to mimic the hierarchical self-assembly of biomacromolec...Interlocked covalent organic cages have aesthetic skeletons endowed with structural and topological complexity.Their self-assembly provides a unique possibility to mimic the hierarchical self-assembly of biomacromolecules.In recent years,significant progresses in interlocked covalent organic cages have been witnessed.Different topological structures have been fabricated via various non-template induced methods,and diverse weak interactions are demonstrated to play critical roles in guiding the formation of interlocked structures.Therefore,this article systematically summarizes the recent advances in interlocked covalent organic cages,especially their design,synthesis,and self-assembly properties.Depending on different types of chemical reactions,irreversible and reversible reactions are separately introduced.In each section,proper monomer selection,critical topology design,key driving forces as well as detailed interlocked mechanisms for the formation of interlocked structures,and their self-assembly behaviors in single crystals are discussed detailedly.Finally,the challenge and future development of interlocked covalent organic cages are briefly prospected.展开更多
A new production line has officially started operating at a green energy industrial park in the Shanxi Yungang Economic Development Zone.Tens of thousands of hair-thin black filaments flow uniformly like gleaming dark...A new production line has officially started operating at a green energy industrial park in the Shanxi Yungang Economic Development Zone.Tens of thousands of hair-thin black filaments flow uniformly like gleaming dark rivers from the winding machines.The Institute of Coal Chemistry of the Chinese Academy of Sciences(CAS)developed T1000-grade high-performance carbon fiber here,and it has fully independent intellectual property rights.“It took us 20 years to go from having‘no grain to cook’to achieving‘high-end iteration,’”said Zhang Shouchun,Deputy Director of the Institute of Coal Chemistry,CAS,and project leader.Behind this striking black thread lies an arduous,persistent campaign of material innovation.展开更多
The highly selective C(sp^(3))-H bond activation strategy will greatly promote the efficient utilization of natural hydrocarbon resources.In the past few decades,chemists have developed effective methods to activate t...The highly selective C(sp^(3))-H bond activation strategy will greatly promote the efficient utilization of natural hydrocarbon resources.In the past few decades,chemists have developed effective methods to activate the 1°C-H bonds with the smallest steric hindrance and the 3°C-H bonds with the largest steric hindrance in alkanes.However,there is currently no effective strategy for activating the 2°C-H bond with steric hindrance between the two.Here,we combine electrochemistry and organic catalysis to report a highly selective method for the chlorination of alkane 2°C-H bonds.By adjusting the specific cavity size of the organic molecule catalyst to precisely undergo hydrogen atom transfer with the secondary C-H bond,the corresponding carbon-centered free radicals are generated,which then combine with chlorine atoms to produce chlorinated alkanes at specific sites.In addition,the use of inexpensive and easily reusable graphite felt electrodes and simple electrochemical conditions makes it easy to scale up the system to kilogram-level production.展开更多
Converting body heat into electricity presents an appealing route for sustainably powering wearable electronics;however,conventional thermoelectric materials face significant drawbacks,including high ionic concentrati...Converting body heat into electricity presents an appealing route for sustainably powering wearable electronics;however,conventional thermoelectric materials face significant drawbacks,including high ionic concentrations,toxicity,and limited thermoelectric efficiency.Here,we report an ionic thermoelectric hydrogel designed through precise supramolecular chemistry,utilizing dual molecular interactions,host-vip complexation ofα-cyclodextrin(α-CD)with I_(3)^(-)ions and hydrogen bonding between polyvinyl alcohol(PVA)polymer chains and I_(3)^(-).This molecularly tailored approach markedly amplifies thermoelectric performance,achieving a high thermopower of 2.21 mV/K and a tenfold enhancement in peak power output at an exceptionally low iodine concentration(10 mmol/L I^(-)+2.5 mmol/L I_(3)^(-)).The hydrogel maintains excellent biocompatibility and mechanical robustness,suitable for direct skin contact.Demonstrated applications include flexible thermoelectric devices generating nearly 100 mV from body heat and sensor arrays capable of motion and spatial temperature sensing.These results underscore the substantial potential of supramolecularly designed ionic thermoelectric hydrogels for wearable energy harvesting,personalized healthcare monitoring,and advanced human-computer interfaces.展开更多
Two-dimensional materials for flexible energy storage commonly facehuge challenges in limited active surface and hindered charge transport.Herein,wereport an innovative asymmetric pseudocapacitor based on synergistic ...Two-dimensional materials for flexible energy storage commonly facehuge challenges in limited active surface and hindered charge transport.Herein,wereport an innovative asymmetric pseudocapacitor based on synergistic design of modifiedMXene and graphene,integrating gas-induced rapid expansion technology andprecise surface chemical regulation methods.For graphene modification,rapid vaporizationinduces exfoliation and expansion of graphene oxide layers.Subsequently,pseudocapacitiveoxygen-containing groups were selectively introduced through acid oxidation,yielding expanded-and-oxidized graphene(OEG)for positive porous-nanopaperelectrode.For MXene modification,alkali-treated MXene underwent hydrazine assistance to facilitate gas expansion and-NH_(2)grafting,producing MXene-NH_(2)(NOM)for negative porous-nanopaper electrode.Density functional theory calculations show that-COOH moreeffectively modulate graphene’s electronic structure by inducing charge redistribution and creating active sites,thereby enhancing H^(+)adsorption and ion interactions compared to-OH.Meanwhile,-NH_(2)on MXene enable electron delocalization and dynamic Ti-N-H^(+)interactions,speeding up proton adsorption/desorption and boosting both pseudocapacitance and conductivity.Through collaborativeoptimized spatial architecture and surface properties,flexible OEGB and NOMB exhibited of 333.6 and 500.5 F g^(-1)at high mass loading,respectively.The assembled proton pseudocapacitor readily achieved energy and power densities of 58.9 Wh kg^(-1)and 3802 W kg^(-1),respectively,with excellent stability for potential applications.展开更多
The Smiles rearrangement is an exceptionally versatile method in organic synthesis,providing a broad canvas for designing cascade reactions that construct new Csp^(2)-Y(Y=C,O,N,S,CO,etc.)bonds.Among the various types ...The Smiles rearrangement is an exceptionally versatile method in organic synthesis,providing a broad canvas for designing cascade reactions that construct new Csp^(2)-Y(Y=C,O,N,S,CO,etc.)bonds.Among the various types of Smiles rearrangement,the radical-type variant has emerged as a more powerful,mild,efficient,and modern synthetic technique compared to its traditional ionic counterpart.This approach excels in generating new(hetero)aromatic migration products,enabling significant advancements in recent years.This tutorial review focuses on the recent progress,since 2016,in the development and application of radical Smiles rearrangement in organic chemistry.Special attention is paid to novel transformations achieved through photochemical,electrochemical,and transition metal catalysis methods.展开更多
The preparation and functionalization of polymeric capsules attract intense attention due to their application in various areas.Herein we presented an amphiphilic alternating copolymer(ACP)-based microcapsule which is...The preparation and functionalization of polymeric capsules attract intense attention due to their application in various areas.Herein we presented an amphiphilic alternating copolymer(ACP)-based microcapsule which is both robust and readily-functionalized through interfacial click polymerization.A water-in-oil emulsion was constructed to act as the reaction medium,the hydrophilic 1,3-butadiene diepoxide(BDE)in water phase reacted with the oleophilic 1,4-dibutanedithiol(BDT)in oil phase at the water-oil interface to form the amphiphilic ACP named poly(2,3-dihydroxy butylene-alt-butylene dithioether)(abbreviated as P(DHB-a-BDT)below),which would deposite in situ to form the micro-sized capsules.Significantly,the dried capsules are robust enough to be rehydrated once the water was added and almost restored their original morphologies.Further elucidation showed that the Young's modulus of these capsules exceeded 1 GPa.As long as we know,it is the first time for the mechanical properties of the ACP-based microstructures being investigated.Besides,functionalization could be achieved simultaneously with the formation process.As a proof of concept,positive-charged capsules were successfully obtained through click copolymerization.Stemming from the unique characteristics of amphiphilic ACPs which combined both merits of click chemistry and interfacial reactions,all these features of the current method as well as the resultant capsules may promote the application of the polymeric capsules.展开更多
Carbon-rich cycloarene macrocycles can adopt multiple atropisomeric forms due to steric hindrance restrictingσ-bond rotation.These distinct conformations exhibit variations in cavity structure,electronic properties,a...Carbon-rich cycloarene macrocycles can adopt multiple atropisomeric forms due to steric hindrance restrictingσ-bond rotation.These distinct conformations exhibit variations in cavity structure,electronic properties,and functional site distribution,leading to diverse molecular recognition and self-assembly behaviors.In recent years,research on carbon-rich cycloarene macrocyclic compounds has emerged as a cutting-edge and interdisciplinary focus in the fields of carbon-rich functional molecules and macrocyclic chemistry.This review provides a comprehensive overview of the development of atropisomers in carbon-rich cycloarene macrocycles,spanning their design and synthesis,optoelectronic properties,and supramolecular chemistry.展开更多
Amid the global pursuit of innovative approaches to disease diagnosis and treatment,the interdisciplinary convergence of chemistry and biomedicine has emerged as a pivotal force driving advancements in the field.Cutti...Amid the global pursuit of innovative approaches to disease diagnosis and treatment,the interdisciplinary convergence of chemistry and biomedicine has emerged as a pivotal force driving advancements in the field.Cutting-edge technologies such as optical probes[1],nanotechnology[2],immunotherapy[3],and biosensors[4]are finding increasingly widespread application in disease diagnosis and treatment,sustaining intense interest from both academia and industry.Against this backdrop,the 5th Xihua Chemistry and Biomedicine Forum was successfully held at Xihua University(Chengdu)from July 12 to 15,2025,infusing new vitality into academic exchanges and innovative progress in this domain.展开更多
While oceanic and coastal acidification has gained increased attention,long-term pH trends and their drivers in large freshwater systems remain poorly understood.The Laurentian Great Lakes are the world’s largest fre...While oceanic and coastal acidification has gained increased attention,long-term pH trends and their drivers in large freshwater systems remain poorly understood.The Laurentian Great Lakes are the world’s largest freshwater system,and in many ways resemble marine ecosystems.However,unlike the open ocean and coastal waters where pH has declined due to rising atmospheric CO_(2),no significant pH trends have been observed in the Laurentian Great Lakes,despite significant ecosystem changes driven partly by the invasion of dreissenid mussels.This study examined 41 years of field observations from Lake Michigan to investigate the long-term carbonate chemistry dynamics.Observational results revealed substantial declines in both total alkalinity(TA)and dissolved inorganic carbon(DIC)over the four decades.Mussel shell calcification emerged as the primary mechanism behind these declines,accounting for 97%and 47%of the observed changes in TA and DIC,respectively,lowering water column pH by 0.24 units.Elevated carbon accumulation in soft mussel tissues,coupled with long-term changes in the air-water pCO_(2)gradient during summer,significantly contributed to long-term DIC variations,explaining 18%and 28%of the lake-wide DIC loss.These two mechanisms also resulted in an overall pH increase of 0.09 and 0.12 units,largely offsetting the calcification-driven pH decrease.These findings bridge a gap in acidification research for large freshwater systems and provide valuable insights for comprehensive lake-wide management strategies.展开更多
文摘Typical feed gas mixtures used in technological and other plasmas may give rise to reaction networks involving several hundred reactions.Such chemistries are often too large to be used in full reactor simulations and it is therefore desirable to construct reduced chemistry networks which mimic as closely as possible the behavior of the full chemistry but employ far fewer individual reactions and species.Constructed chemistries are available from the Quantemol database (QDB) and two approaches to constructing reduced chemistry from these chemistries based on (a) physical intuition and (b) sensitivity analysis of dominant reaction pathways,are explored.In doing this it is necessary to consider different pressure and power regimes.Reduced chemistry sets are presented for CF4/O2/N2/H2,for which 396 reactions and 52 species are reduced to 71 reactions and 26 species,and for pure O2,for which 45 reactions and 10 species are reduced to 34 reactions.
文摘BACKGROUND Coronavirus disease(COVID-19)patients exhibit different patterns of liver impairment,according to growing evidence.AIM In this study,we sought to provide a comprehensive analysis of liver test parameters in patients with severe and non-severe COVID-19.METHODS We performed a meta-analysis of published liver manifestations and described the liver damage in COVID-19.We searched PubMed,Google Scholar,Embase,Cochrane Library,medRxiv,bioRxiv,and three Chinese electronic databases through April 18,2020,in accordance with the Preferred Reporting Items for Meta-Analyses.We analyzed pooled data on liver chemistries stratified by COVID-19 severity using a fixed or random-effects model.RESULTS A meta-analysis of 56 studies,including 11052 patients,found that the pooled mean alanine aminotransferase(ALT)in severe COVID-19 cases was 35.9 IU/L whereas in non-severe COVID-19 cases was 27.3 IU/L.Average aspa-rtate aminotransferase(AST)levels were 44.3 IU/L in severe cases compared to 27.9 IU/L in non-severe cases.In addition,AST levels are often higher than ALT levels regardless of disease severity.The severe cases tended to have a higher gammaglutamyltransferase level but a lower albumin level than the non-severe cases.CONCLUSION Severe COVID-19 was more likely to be associated with abnormal liver test results.Monitoring liver chemistry closely can help detect disease progression early.
基金supported by the National Natural Science Foundation of China(Nos.51873111,51721091)the Scientific Research Foundation of Sichuan Province(No.2018HH0001)+1 种基金the Programme of Introducing Talents of Discipline to Universities(No.B13040)the Graduate Innovation Foundation of Sichuan University(No.2018YJSY088).
文摘Silica rods with homogeneous(hydrophilic or hydrophobic)and amphiphilic surface properties were synthesized and their efficiencies in suppressing the flow-induced droplet coalescence of immiscible polyisobutylene(PIB)/polydimethylsiloxane(PDMS)blends were evaluated via in situ visualization technique.The flow-induced coalescence behavior of blends was found to strongly depend on the surface nature and concentration of silica rods added as well as the blend ratio.While a trace amount of rods promoted coalescence,all kinds of rods demonstrated a morphology refinement effect at high rod concentrations.Good compatibilization effects were obtained at high rod concentrations,especially for hydrophilic and amphiphilic rods.Based on confocal laser scanning microscopy results,these phenomena observed were interpreted reasonably in terms of the selective distribution and aggregation of silica rods,which were suggested to be decisive for the stabilization mechanism and efficiency of these rods.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB 0470303)the National Natural Science Foundation of China(No.52305225 and 51935012)the Chinese Academy of Sciences Project for Young Scientists in Basic Research(No.YSBR-023).
文摘Recently,the focus of materials research has shifted toward intelligent materials and structures with customizable properties and stimulus-responsive functions.Here,a recyclable thermosetting epoxy resin with self-reported wear and customizable friction is achieved through dynamic and reversible molecular structure design.The epoxy vitrimer displays exceptional mechanical properties,with a Young's modulus of 2.3 GPa,elongation at break of 7.1%,and tensile strength of 79.25 MPa.Based on the reversible exchange of dynamic covalent bonds,the epoxy vitrimer can be fully recovered through hot pressing without the need for additional adhesives or catalysts,and even self-healing can be achieved.Furthermore,by utilizing the reversibility of dynamic covalent bonds,nanofillers(graphene oxide(GO)and polytetrafluoroethylene(PTFE))with specific tribological properties are incorporated into the recovery process to achieve customizable friction coefficients and wear rates.The self-reported characteristics of wear based on sulfur radicals are realized by exploiting the dynamic nature of disulfide bonds.The correlation between wear time and wear state is investigated.The molecular structure design of epoxy based on dynamic covalent bonds has resulted in a versatile thermosetting material with self-reporting and customizable friction properties that is ideal for sustainable engineering and friction applications.This enables intelligent manufacturing while reducing resource waste.
基金funded by the German Federal Ministry for Economic Affairs and Climate Action(SUSTAIN,16BZF320B).
文摘Recycling and second life of lithium-ion batteries are vital for lowering the growing resource demand of sectors like mobility or home energy storage.However,an often-overlooked issue is the sometimes-unknown cell chemistry of batteries entering the end-of-life.In this work,a machine learning based approach for the identi-fication of lithium-ion battery cathode chemistries is presented.First,an initial measurement boundary deter-mination is introduced.Using the Python Battery Mathematical Modelling(PyBaMM)framework,synthetical partial open circuit voltage(OCV)charge and discharge curves are generated with an electrochemical single particle model for three different cathode chemistries and the initial state of charge and state of health values as well as the initial capacities are varied.The dV/dQ characteristics are chosen as features and four machine learning algorithms are trained on different lengths of OCV curves.The trade-off between achievable accuracy and the number of OCV steps showed that an increasing accuracy correlates with a higher step number.While extremely small charge and discharge capacities per step did not yield sufficient testing accuracies,capacities starting from 0.2 Ah per step up to 0.6 Ah per step showed increasingly good results with an accuracy of up to 89.3%for 0.5 Ah and 15 OCV steps.Additionally,the approach was validated by classifying experimental data.The results especially demonstrate the effectiveness of the approach to distinguish between lithium iron phos-phate(LFP)and lithium nickel manganese cobalt(NMC)cells.
文摘Food Science and Human Wellness(FSHW ISSN:2213-4530,CN 10-1750/TS)publishes original research papers demonstrating the latest advancement of multidisci-plinary subjects related to food science and human health..Topics may include but not limited to:nutriology,bio-chemistry,microbiology,immunology and toxicology.
基金Support by National Natural Science Foundation of China(22127802,22573091)the HY Action(62402010305)。
文摘Biomass-based hydrocarbon fuels,as one of the alternatives to traditional fossil fuels,have attracted considerable attention in the energy field due to their renewability and environmental benefits.This article provides a systematic review of recent research progress in the chemical synthesis of biomass-based hydrocarbon fuels.It outlines the conversion pathways using feedstocks such as lipids,terpenoids,cellulose/hemicellulose,and lignin.Depending on the feedstock,various products with distinct structural characteristics can be prepared through reactions such as cyclization,condensation,and catalytic hydrogenation.Throughout the synthesis process,three key factors play a critical role:efficient catalyst development,production process optimization,and computational-chemistry-based molecular design.Finally,the article discusses future perspectives for biomass-based hydrocarbon fuel synthesis research.
文摘The complexes 1-4 of cyclobutanocucurbit[5]uril(CyB5Q[5])with Na^(+)/K^(+)have been synthesized and characterized by single-crystal X-ray diffraction.The results show that although the inorganic salts are used when the cations are the same and the anions are different,in complex 1,Na^(+)closes one port of CyB5Q[5]through Na—O seven coordination bonds to form a molecular bowl;in complex 3,Na^(+)completely closes the two ports of CyB5Q[5]to form a molecular capsule with six Na—O coordination bonds;in complexes 2 and 4,the two ports of CyB5Q[5]are completely closed to form K—O coordinated molecular capsules,but the K^(+)of complex 2 is six-coordinated and that of complex 4 is eight-/nine-coordinated.and complex 4 are connected by three oxygen bridges to form a 1D molecular chain.CCDC:2457122,1;2457121,2;2457400,3;2457120,4.
文摘Chinese Chemical Letters(CCL)(ISSN 1001-8417)was founded in July 1990.The journal publishes preliminary accounts in the whole field of chemistry,including inorganic chemistry,organic chemistry,analytical chemistry,physical chemistry,polymer chemistry,applied chemistry,etc.,satisfying a real and urgent need for the dissemination of research results,especially hot topics.The journal does not accept articles previously published or scheduled to be published.To verify originality,your article may be checked by the originality detection service Cross Check.
基金supported by the National Natural Science Foundation of China (Nos.22271010 and 21702013)。
文摘The deuterium labeling has garnered significant interest in drug discovery due to its critical role on improving pharmacokinetic and metabolic properties.However,despite its pharmaceutical value,the general and rapid syntheses of aromatic scaffolds that contains deuterium remain an important yet elusive task.State-of-the-art approaches mainly relied on the transition metal-catalyzed C-H deuteration via the assistance of directing groups(DGs),which often suffered from over-deuteration and lengthy step counts required for installation and/or removal of DG.Herein,we report a generalizable synthetic linchpin strategy for the facile preparation of the ortho-deuterated aromatic core.Through capture of aryne-derived 1,3-zwitterion with heavy water,we synthesized an array of ortho-deuterated aryl sulfonium salts.These novel linchpins not only participated the transition metal catalyzed cross-coupling reaction as nucleophiles,but also served as aryl radical reservoirs under photochemical or electrochemical conditions,enabling facile and precise access to structurally diverse deuterated aromatics.Moreover,we have disclosed a novel EDA complex enabled direct arylation of phosphines under visible-light irradiation,further expanding the utility of our platform approach.
基金supported by the Science and Technology Research Program of Chongqing Municipal Education Commission (No.KJQN202400807)Natural Science Foundation of Shanghai (No.23ZR1419600)。
文摘Interlocked covalent organic cages have aesthetic skeletons endowed with structural and topological complexity.Their self-assembly provides a unique possibility to mimic the hierarchical self-assembly of biomacromolecules.In recent years,significant progresses in interlocked covalent organic cages have been witnessed.Different topological structures have been fabricated via various non-template induced methods,and diverse weak interactions are demonstrated to play critical roles in guiding the formation of interlocked structures.Therefore,this article systematically summarizes the recent advances in interlocked covalent organic cages,especially their design,synthesis,and self-assembly properties.Depending on different types of chemical reactions,irreversible and reversible reactions are separately introduced.In each section,proper monomer selection,critical topology design,key driving forces as well as detailed interlocked mechanisms for the formation of interlocked structures,and their self-assembly behaviors in single crystals are discussed detailedly.Finally,the challenge and future development of interlocked covalent organic cages are briefly prospected.
文摘A new production line has officially started operating at a green energy industrial park in the Shanxi Yungang Economic Development Zone.Tens of thousands of hair-thin black filaments flow uniformly like gleaming dark rivers from the winding machines.The Institute of Coal Chemistry of the Chinese Academy of Sciences(CAS)developed T1000-grade high-performance carbon fiber here,and it has fully independent intellectual property rights.“It took us 20 years to go from having‘no grain to cook’to achieving‘high-end iteration,’”said Zhang Shouchun,Deputy Director of the Institute of Coal Chemistry,CAS,and project leader.Behind this striking black thread lies an arduous,persistent campaign of material innovation.
基金supported by the National Natural Science Foundation of China(22371129)the First Class Discipline of Traditional Chinese Medicine“Leading Plan”Scientific Research Special Project of Nanjing University of Chinese Medicine(ZYXPY2024-005)。
文摘The highly selective C(sp^(3))-H bond activation strategy will greatly promote the efficient utilization of natural hydrocarbon resources.In the past few decades,chemists have developed effective methods to activate the 1°C-H bonds with the smallest steric hindrance and the 3°C-H bonds with the largest steric hindrance in alkanes.However,there is currently no effective strategy for activating the 2°C-H bond with steric hindrance between the two.Here,we combine electrochemistry and organic catalysis to report a highly selective method for the chlorination of alkane 2°C-H bonds.By adjusting the specific cavity size of the organic molecule catalyst to precisely undergo hydrogen atom transfer with the secondary C-H bond,the corresponding carbon-centered free radicals are generated,which then combine with chlorine atoms to produce chlorinated alkanes at specific sites.In addition,the use of inexpensive and easily reusable graphite felt electrodes and simple electrochemical conditions makes it easy to scale up the system to kilogram-level production.
基金supported by the National Natural Science Foundation of China(22271110)the Natural Science Founda-tion of Hubei Province(2022CFA031)。
文摘Converting body heat into electricity presents an appealing route for sustainably powering wearable electronics;however,conventional thermoelectric materials face significant drawbacks,including high ionic concentrations,toxicity,and limited thermoelectric efficiency.Here,we report an ionic thermoelectric hydrogel designed through precise supramolecular chemistry,utilizing dual molecular interactions,host-vip complexation ofα-cyclodextrin(α-CD)with I_(3)^(-)ions and hydrogen bonding between polyvinyl alcohol(PVA)polymer chains and I_(3)^(-).This molecularly tailored approach markedly amplifies thermoelectric performance,achieving a high thermopower of 2.21 mV/K and a tenfold enhancement in peak power output at an exceptionally low iodine concentration(10 mmol/L I^(-)+2.5 mmol/L I_(3)^(-)).The hydrogel maintains excellent biocompatibility and mechanical robustness,suitable for direct skin contact.Demonstrated applications include flexible thermoelectric devices generating nearly 100 mV from body heat and sensor arrays capable of motion and spatial temperature sensing.These results underscore the substantial potential of supramolecularly designed ionic thermoelectric hydrogels for wearable energy harvesting,personalized healthcare monitoring,and advanced human-computer interfaces.
基金supported by the National Nature Science Foundation of China(No.52402126)Shaanxi Province Qin Chuangyuan general window four chain integration project(No.2024PT-ZCK-09)+3 种基金Shaanxi Province military-civilian integration project(Shaanxi finance office【2024】22nd)Qinchuangyuan introducing high-level innovation and entrepreneurship talent projects(NO.QCYRCXM-2022-343)the China Postdoctoral Science Foundation(Grant Number:2025M772524)National Nature Science Foundation of China(22508239).
文摘Two-dimensional materials for flexible energy storage commonly facehuge challenges in limited active surface and hindered charge transport.Herein,wereport an innovative asymmetric pseudocapacitor based on synergistic design of modifiedMXene and graphene,integrating gas-induced rapid expansion technology andprecise surface chemical regulation methods.For graphene modification,rapid vaporizationinduces exfoliation and expansion of graphene oxide layers.Subsequently,pseudocapacitiveoxygen-containing groups were selectively introduced through acid oxidation,yielding expanded-and-oxidized graphene(OEG)for positive porous-nanopaperelectrode.For MXene modification,alkali-treated MXene underwent hydrazine assistance to facilitate gas expansion and-NH_(2)grafting,producing MXene-NH_(2)(NOM)for negative porous-nanopaper electrode.Density functional theory calculations show that-COOH moreeffectively modulate graphene’s electronic structure by inducing charge redistribution and creating active sites,thereby enhancing H^(+)adsorption and ion interactions compared to-OH.Meanwhile,-NH_(2)on MXene enable electron delocalization and dynamic Ti-N-H^(+)interactions,speeding up proton adsorption/desorption and boosting both pseudocapacitance and conductivity.Through collaborativeoptimized spatial architecture and surface properties,flexible OEGB and NOMB exhibited of 333.6 and 500.5 F g^(-1)at high mass loading,respectively.The assembled proton pseudocapacitor readily achieved energy and power densities of 58.9 Wh kg^(-1)and 3802 W kg^(-1),respectively,with excellent stability for potential applications.
基金Financial support from the Fundamental Research Funds for Gannan Medical University(No.QD202429)National Natural Science Foundation of China(No.22171206)+2 种基金Natural Science Foundation of Zhejiang Province(No.LZ23B020001)Zhejiang Provincial Ten Thousand Talent Program(No.2023R5244)Open Research Fund of School of Chemistry and Chemical Engineering,Henan Normal University(No.2020ZD04)is gratefully acknowledged.
文摘The Smiles rearrangement is an exceptionally versatile method in organic synthesis,providing a broad canvas for designing cascade reactions that construct new Csp^(2)-Y(Y=C,O,N,S,CO,etc.)bonds.Among the various types of Smiles rearrangement,the radical-type variant has emerged as a more powerful,mild,efficient,and modern synthetic technique compared to its traditional ionic counterpart.This approach excels in generating new(hetero)aromatic migration products,enabling significant advancements in recent years.This tutorial review focuses on the recent progress,since 2016,in the development and application of radical Smiles rearrangement in organic chemistry.Special attention is paid to novel transformations achieved through photochemical,electrochemical,and transition metal catalysis methods.
基金financially supported by the Fundamental Research Funds for Central Universities(No.24D110627)。
文摘The preparation and functionalization of polymeric capsules attract intense attention due to their application in various areas.Herein we presented an amphiphilic alternating copolymer(ACP)-based microcapsule which is both robust and readily-functionalized through interfacial click polymerization.A water-in-oil emulsion was constructed to act as the reaction medium,the hydrophilic 1,3-butadiene diepoxide(BDE)in water phase reacted with the oleophilic 1,4-dibutanedithiol(BDT)in oil phase at the water-oil interface to form the amphiphilic ACP named poly(2,3-dihydroxy butylene-alt-butylene dithioether)(abbreviated as P(DHB-a-BDT)below),which would deposite in situ to form the micro-sized capsules.Significantly,the dried capsules are robust enough to be rehydrated once the water was added and almost restored their original morphologies.Further elucidation showed that the Young's modulus of these capsules exceeded 1 GPa.As long as we know,it is the first time for the mechanical properties of the ACP-based microstructures being investigated.Besides,functionalization could be achieved simultaneously with the formation process.As a proof of concept,positive-charged capsules were successfully obtained through click copolymerization.Stemming from the unique characteristics of amphiphilic ACPs which combined both merits of click chemistry and interfacial reactions,all these features of the current method as well as the resultant capsules may promote the application of the polymeric capsules.
基金H.-Y.Gong is grateful to the National Natural Science Foundation of China(No.92156009)for financial Support.
文摘Carbon-rich cycloarene macrocycles can adopt multiple atropisomeric forms due to steric hindrance restrictingσ-bond rotation.These distinct conformations exhibit variations in cavity structure,electronic properties,and functional site distribution,leading to diverse molecular recognition and self-assembly behaviors.In recent years,research on carbon-rich cycloarene macrocyclic compounds has emerged as a cutting-edge and interdisciplinary focus in the fields of carbon-rich functional molecules and macrocyclic chemistry.This review provides a comprehensive overview of the development of atropisomers in carbon-rich cycloarene macrocycles,spanning their design and synthesis,optoelectronic properties,and supramolecular chemistry.
文摘Amid the global pursuit of innovative approaches to disease diagnosis and treatment,the interdisciplinary convergence of chemistry and biomedicine has emerged as a pivotal force driving advancements in the field.Cutting-edge technologies such as optical probes[1],nanotechnology[2],immunotherapy[3],and biosensors[4]are finding increasingly widespread application in disease diagnosis and treatment,sustaining intense interest from both academia and industry.Against this backdrop,the 5th Xihua Chemistry and Biomedicine Forum was successfully held at Xihua University(Chengdu)from July 12 to 15,2025,infusing new vitality into academic exchanges and innovative progress in this domain.
基金Supported by the National Natural Science Foundation of China(No.43277051)the Key Laboratory of Integrated Regulation and Resources Development of Shallow Lakes of Ministry of Education(No.B230203006).
文摘While oceanic and coastal acidification has gained increased attention,long-term pH trends and their drivers in large freshwater systems remain poorly understood.The Laurentian Great Lakes are the world’s largest freshwater system,and in many ways resemble marine ecosystems.However,unlike the open ocean and coastal waters where pH has declined due to rising atmospheric CO_(2),no significant pH trends have been observed in the Laurentian Great Lakes,despite significant ecosystem changes driven partly by the invasion of dreissenid mussels.This study examined 41 years of field observations from Lake Michigan to investigate the long-term carbonate chemistry dynamics.Observational results revealed substantial declines in both total alkalinity(TA)and dissolved inorganic carbon(DIC)over the four decades.Mussel shell calcification emerged as the primary mechanism behind these declines,accounting for 97%and 47%of the observed changes in TA and DIC,respectively,lowering water column pH by 0.24 units.Elevated carbon accumulation in soft mussel tissues,coupled with long-term changes in the air-water pCO_(2)gradient during summer,significantly contributed to long-term DIC variations,explaining 18%and 28%of the lake-wide DIC loss.These two mechanisms also resulted in an overall pH increase of 0.09 and 0.12 units,largely offsetting the calcification-driven pH decrease.These findings bridge a gap in acidification research for large freshwater systems and provide valuable insights for comprehensive lake-wide management strategies.
