Attaining the selective oxidation of isochroman into isochromanone in a molecular oxygen(O_(2))environment without any additives,via a heterogeneous oxidation process,is highly desirable and challenging work.Herein,we...Attaining the selective oxidation of isochroman into isochromanone in a molecular oxygen(O_(2))environment without any additives,via a heterogeneous oxidation process,is highly desirable and challenging work.Herein,we prepare two mixed-addendum polyoxometalate-based coordination polymers of the general formula[H_(x)M_(1-x)(i-PrIm)_(4)][H_(2)N(CH_(3))_(2)]_(4)[HPMo_(8)V_(6)O_(42)](M=Co 1,Ni,2;i-PrIm=1-isopropyl-1H-imidazole).Needing no additives,they can catalyze the selective oxidation of isochroman to isochromanone with O_(2)as an oxidant,with yields of 91.5%(1)and 46.8%(2),respectively.Mechanistic studies indicate that the excellent performance of catalyst 1 is attributed to the synergistic operation of[Co(i-Pr-Im)_(4))]complex and PMo_(8)V_(6)unit,and that the catalytic reaction is a radical pathway involving superoxide radicals.Additionally,the catalyst 1 can be recycled and reused at least four times with uncompromised performance.These results provide fundamental guidelines for designing efficient and multi-site heterogeneous catalysts for the selective oxidation of benzyl C(sp^(3))-H bonds by activating O_(2).展开更多
The synergistic effect of low Gd+Mn additions on the evolution of microstructure and mechanical properties of Mg−xGd−0.8Mn alloy was investigated.Gd addition shows a strong grain refinement effect on the extruded Mg−x...The synergistic effect of low Gd+Mn additions on the evolution of microstructure and mechanical properties of Mg−xGd−0.8Mn alloy was investigated.Gd addition shows a strong grain refinement effect on the extruded Mg−xGd−0.8Mn alloy,and leads to a continuous decrease in the area fraction of basal texture grains and the corresponding maximum density of texture components.However,the maximum density of the basal texture components grows abruptly as Gd content increases to 6 wt.%.When the Gd content is below 6 wt.%,the asymmetry of the tensile and compressive yield of the alloy is negatively correlated to the Gd content due to grain refinement and texture weakening effects.Besides,the contribution of grain refinement to higher alloy yield strength is more significant than that of grain orientation.Compared with the extruded Mg−xGd alloy,the extruded Mg−xGd−0.8Mn alloy shows a lower limit composition point that corresponds to solid solution strengthening and plasticizing effect(2 wt.%and 4 wt.%).Finally,the trend of basal slip and prismatic slip resistance variations of the extruded Mg−xGd−0.8Mn alloys was predicted.展开更多
Binuclear complexes have attracted extensive attention in fields such as catalysis because of their likely bimetallic synergistic effect;however,the mechanism and factors influencing this synergism remain unclear.In t...Binuclear complexes have attracted extensive attention in fields such as catalysis because of their likely bimetallic synergistic effect;however,the mechanism and factors influencing this synergism remain unclear.In this work,six bis-β-ketoimine binuclear titanium complexes4a-4f containing different alkylthio sidearms and configurations were synthesized and characterized by nuclear magnetic resonance hydrogen spectrum(~1H-NMR),nuclear magnetic resonance carbon spectrum(^(13)C-NMR),Fourier transform infrared spectrum(FTIR),and elemental analysis.The intermetallic distances of isomeric complexes 4a,4d,4e and 4f determined through density functional theory(DFT)optimization were in the order 4a<4d<4e<4f and were found to significantly influence the catalytic performance for ethylene(co)polymerization.These complexes could efficiently catalyze ethylene polymerization and ethylene/1-hexene or ethylene/1-octene copolymerization with high activity to produce highmolecular-weight ethylene homo-and co-polymers.Among the three binuclear titanium complexes 4a-4c with similar structures but different lengths of alkylthio sidearms,complex 4a,which contained the shortest methylthio sidearm,exhibited the highest activity for ethylene polymerization and copolymerization with 1-hexene or 1-octene.Additionally,for ethylene/1-hexene or ethylene/1-octene copolymerization,it showed the highest comonomer incorporation compared with propylthio(4b)and octylthio(4c)derivatives because of the smaller steric hindrance of the methyl group in 4a and the more open coordination space for vinyl monomers.Furthermore,among the isomeric complexes 4a,4d,4e and4f,complex 4a with the shortest bimetallic distance also exhibited the highest activity towards ethylene(co)polymerization,and the highest 1-hexene or 1-octene incorporation in comparison with its regioisomeric counterparts 4d,4e and p-phenyl-bridged analog 4f,owing to a more appropriate bimetallic distance that is conducive to a synergistic effect.展开更多
Bulk metallic glasses(BMGs)are typically characterized by high strength and elasticity.However,they generally demonstrate a deficiency in plastic deformation capability at room temperatures.In this work,Cu_(50-x)Zr_(4...Bulk metallic glasses(BMGs)are typically characterized by high strength and elasticity.However,they generally demonstrate a deficiency in plastic deformation capability at room temperatures.In this work,Cu_(50-x)Zr_(46)Al4Agx(x=0,1,2,3,4)alloys were prepared by arc melting and copper mold casting to investigate their structure,glass-forming ability,and mechanical properties.The results show that the addition of Ag can increase the parameter of DTx and g in Cu_(50)Zr_(46)Al_(4)alloy by 116%and 1.5%respectively,effectively enhancing its thermal stability and glass-forming ability.Compressive fracture tests reveal that the addition of Ag can significantly improve the yield strength,ultimate strength,and plasticity of the Cu_(50)Zr_(46)Al_(4)alloy.Specifically,with the Ag addition of 1 at.%,the alloy’s ultimate strength and plasticity increased by 71.8%and 21 times,respectively.Furthermore,the introduction of Ag can effectively control the free volume content in the Cu_(50)Zr_(46)Al_(4)alloy,thereby tuning the hardness of the material.This work provides valuable insights into improving the mechanical performance of BMGs through micro-alloying approaches.展开更多
The antioxidant and anti-wrinkle firming effects of a combination of vitamin C(Vc)and black Ganoderma lucidum extract was evaluted.Through the DPPH radical scavenging model and elastase inhibition model,this research ...The antioxidant and anti-wrinkle firming effects of a combination of vitamin C(Vc)and black Ganoderma lucidum extract was evaluted.Through the DPPH radical scavenging model and elastase inhibition model,this research investigates the impact of these substances individually and in combination on antioxidant capabilities and anti-wrinkle firming effects.The results demonstrate that the combination of Vc and black Ganoderma lucidum extract exhibits significant antioxidant abilities at various concentrations,and is more effective than when each is used separately,indicating a synergistic interaction between them.Additionally,the combination also shows significant inhibition of elastase,suggesting potential applications in delaying the aging process of the skin.Furthermore,highperformance liquid chromatography(HPLC)was used to determine if reactions occur among the components of the mixture.The findings reveal that the concentration of Vc in the mixture is very close to the theoretical concentration and relatively stable,suggesting that the components function independently.A quantitative analysis using the Bliss independence model further confirms the synergistic effects of Vc and black Ganoderma lucidum extract at specific ratios,providing a scientific basis for the development of efficacious cosmetic products.展开更多
Electrocatalytic water splitting for hydrogen production is a key approach to tackling the current energy crisis.Among the catalysts,the traditional Pd@C catalysts are remarkable for their efficiency in hydrogen evolu...Electrocatalytic water splitting for hydrogen production is a key approach to tackling the current energy crisis.Among the catalysts,the traditional Pd@C catalysts are remarkable for their efficiency in hydrogen evolution.However,the high cost and scarcity of Pd catalysts,as well as the instability caused by the corrosiveness of carbon-based substrates,hinder their large-scale application.To overcome this challenge,an effective strategy is to construct highly dispersed Pd single atoms to improve palladium utilization and choose more stable materials as supports.In this study,TiO_(2-x)carriers with abundant oxygen vacancies were prepared and loaded with Pd by photoreduction deposition.Adjusting the palladium content resulted in three forms of Pd-loaded TiO_(2-x):nanoparticles(Pd@TiO_(2-x)(6%,10%)),nanoclusters(Pd@TiO_(2-x)(3%))and single atoms(Pd@TiO_(2-x)(1.5%)).The oxygen vacancies improved the stability of the titanium dioxide materials by providing more active hydrogen adsorption sites and increasing the affinity of Pd for active hydrogen.Single atom loading increased the frequency of oxygen holes in the support and the high activity of monatomic Pd promoted the adsorption of active hydrogen and facilitated the formation of active hydrogen intermediates.The synergistic effect of single atoms and oxygen vacancies improved the stability and catalytic activity of the composite material.Pd@TiO_(2-x)(1.5%)showed outstanding performance in hydrogen evolution in an acidic medium with an overpotential of only 24 m V at a current density of 10 m A/cm^(2)and a low Tafel rise of 41.9 m V/dec.This study provides an effective strategy for the development of high-performance hydrogen evolution(HER)catalysts.展开更多
Organic additives with multiple functional groups have shown great promise in improving the performance and stability of perovskite solar cells.The functional groups can passivate undercoordinated ions to reduce nonra...Organic additives with multiple functional groups have shown great promise in improving the performance and stability of perovskite solar cells.The functional groups can passivate undercoordinated ions to reduce nonradiative recombination losses.However,how these groups synergistically affect the enhancement beyond passivation is still unclear.Specifically,isomeric molecules with different substitution patterns or molecular shapes remain elusive in designing new organic additives.Here,we report two isomeric carbazolyl bisphosphonate additives,2,7-Cz BP and 3,6-Cz BP.The isomerism effect on passivation and charge transport process was studied.The two molecules have similar passivation effects through multiple interactions,e.g.,P=O···Pb,P=O···H–N and N–H···I.2,7-CzBP can further bridge the perovskite crystallites to facilitates charge transport.Power conversion efficiencies(PCEs)of 25.88%and 21.04%were achieved for 0.09 cm^(2)devices and 14 cm^(2)modules after 2,7-Cz BP treatment,respectively.The devices exhibited enhanced operational stability maintaining 95%of initial PCE after 1000 h of continuous maximum power point tracking.This study of isomerism effect hints at the importance of tuning substitution positions and molecular shapes for organic additives,which paves the way for innovation of next-generation multifunctional aromatic additives.展开更多
Power cables are important pieces of equipment for energy transmission,but achieving a good balance between flame retardancy and mechanical properties of cable sheaths remains a challenge.In this work,a novel intumesc...Power cables are important pieces of equipment for energy transmission,but achieving a good balance between flame retardancy and mechanical properties of cable sheaths remains a challenge.In this work,a novel intumescent flame retardant(IFR)system containing silicone-containing macromolecular charring agent(Si-MCA)and ammonium polyphosphate(APP)was designed to synergistically improve the flame retardancy and mechanical properties of ethylene-butyl acrylate copolymer(EBA)composites.The optimal mass ratio of APP/Si-MCA was 3/1 in EBA composites(EBA/APP-Si-31),corresponding to the best flame retardancy with 31.2% of limited oxygen index(LOI),V-0 rating in UL-94 vertical burning test,and 76.4%reduction on the peak of heat release rate(PHRR)in cone calorimeter test.The enhancement mechanism was attributed to the synergistic effect of APP/Si-MCA during combustion,including the radical-trapping effect,the dilution effect of non-flammable gases,and the barrier effect of the intumescent char layer.Meanwhile,the tensile results indicated that EBA/APP-Si-31 also exhibited good mechanical properties with the addition of maleic anhydride-grafted polyethylene(PE-g-MA)as the compatibilizer.Thus,the APP/Si-MCA combination is an effective IFRs system for preparing high-performance EBA composites,and it will promote their applications as cable sheath materials.展开更多
Ionic liquids(ILs),recognized for their negligible vapor pressure,thermal stability,and structural tailorability,offer targeted inhibition of clay expansion.Compared to ILs,polyionic liquids(PILs)possess stronger mech...Ionic liquids(ILs),recognized for their negligible vapor pressure,thermal stability,and structural tailorability,offer targeted inhibition of clay expansion.Compared to ILs,polyionic liquids(PILs)possess stronger mechanical properties and adsorption capabilities,showing even greater potential in inhibiting clay swelling.In this work,we synthesized and characterized an imidazole-based ionic liquid(IL-NH_(2)),a polyionic liquid(PIL-ABHIm),and a PIL/IL combination.Their inhibitory performance was rigorously evaluated under simulated drilling conditions through immersion tests,linear swelling tests,among others.Additionally,the mechanisms underlying their interaction with clay minerals were elucidated through contact angle measurements,Fourier-transform infrared spectroscopy,X-ray diffraction(XRD),Zeta potential analysis,and molecular electrostatic potential(MEP)analysis.This work demonstrates that IL-NH_2inhibits osmotic hydration by altering the interlayer structure of the clay,while PIL-ABHIm reduces surface hydration by forming a hydrophobic barrier on the clay surface.PIL/IL combines both mechanisms,significantly enhancing the stability of clay through the dual mechanisms of cation exchange and hydrophobic barriers.These findings reveal an innovative mechanism by which PIL/IL combination inhibits clay hydration and swelling,providing a scientific foundation for their application in drilling fluids.展开更多
Ulcerative colitis(UC)is a chronic inflammatory disorder with a complex etiology,characterized by intestinal inflammation and barrier dysfunction.Platycodon grandiflorus polysaccharides(PGP),the primary component of P...Ulcerative colitis(UC)is a chronic inflammatory disorder with a complex etiology,characterized by intestinal inflammation and barrier dysfunction.Platycodon grandiflorus polysaccharides(PGP),the primary component of Platycodon grandiflorus,and hesperidin(Hesp),a prominent active component in Citrus aurantium L.(CAL),have both demonstrated anti-inflammatory properties.This study aims to elucidate the underlying mechanism of the synergistic effect of PGP combined with Hesp on UC,focusing on the coordinated interaction between the phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT)and Janus kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3)signaling pathways.A mouse model of UC induced by dextran sulfate sodium(DSS)and a cell model using lipopolysaccharide(LPS)-induced RAW264.7/IEC6 cells were employed to investigate the in vitro and in vivo anti-inflammatory effects of PGP combined with Hesp on UC and its potential mechanism of action.The results indicated that compared to the effects of either drug alone,the combination of PGP and Hesp significantly modulated inflammatory factor levels,inhibited oxidative stress,regulated colonic mucosal immunity,suppressed apoptosis,and restored intestinal barrier function in vitro and in vivo.Further in vitro studies revealed that PGP significantly inhibited the PI3K/AKT signaling pathway,while Hesp significantly inhibited the JAK2/STAT3 signaling pathway.The use of inhibitors and activators targeting both pathways validated the synergistic effects of PGP combined with Hesp on the PI3K/AKT and JAK2/STAT3 signaling pathways.These findings suggest that PGP combined with Hesp exhibits a synergistic effect on DSS-induced colitis,potentially mediated through the phosphatase and tensin homolog(PTEN)/PI3K/AKT and interleukin-6(IL-6)/JAK2/STAT3 signaling pathways.展开更多
Lithium-sulfur batteries(LSBs)are considered as the most promising energy storage technologies owing to their large theoretical energy density(2500Wh/kg)and specific capacity(1675 mAh/g).However,the heavy shuttle effe...Lithium-sulfur batteries(LSBs)are considered as the most promising energy storage technologies owing to their large theoretical energy density(2500Wh/kg)and specific capacity(1675 mAh/g).However,the heavy shuttle effect of polysulfides and the growth of lithium dendrites greatly hinder their further development and commercial application.In this paper,cobalt-molybdenum bimetallic carbides heterostructure(Co_(6)Mo_(6)C_(2)@Co@NC)was successfully prepared through chemical etching procedure of ZIF-67 precursor with sodium molybdate and the subsequent high temperature annealing process.The obtained dodecahedral Co_(6)Mo_(6)C_(2)@Co@NC with hollow and porous structure provides large specific surface area and plentiful active sites,which speeds up the chemisorption and catalytic conversion of polysulfides,thus mitigating the shuttle effect of polysulfides and the generation of lithium dendrites.When applied as the LSBs separator modifier layer,the cell with modified separator present excellent rate capability and durable cycling stability.In particular,the cell with Co_(6)Mo_(6)C_(2)@Co@NC/PP separator can maintain the high capacity of 738 mAh/g at the current density of 2 C and the specific capacity of 782.6 mAh/g after 300 cycles at 0.5 C,with the coulombic efficiency(CE)near to 100%.Moreover,the Co_(6)Mo_(6)C_(2)@Co@NC/PP battery exhibits the impressive capacity of 431 mAh/g in high sulfur loading(4.096 mg/cm^(2))at 0.5 C after 200 cycles.This work paves the way for the development of bimetallic carbides heterostructure multifunctional catalysts for durable Li-S battery applications and reveals the synergistic regulation of polysulfides and lithium dendrites through the optimization of the structure and composition.展开更多
Electrodeposition of acid copper plating on mild steel substrate is tedious due to the galvanic displacement reaction ofcopper on mild steel.This can be avoided by using a proper complexing agent,because the complexin...Electrodeposition of acid copper plating on mild steel substrate is tedious due to the galvanic displacement reaction ofcopper on mild steel.This can be avoided by using a proper complexing agent,because the complexing agent tuned the potential ofnoble direction to less noble direction by complex formation.In this paper,environment friendly electrodeposition of copper fromnon-cyanide electrolyte using sodium gluconate as complexing agent was investigated in alkaline medium.The effects of additivessuch as1,2,3-benzotriazole,sodium lauryl sulphate,PEG8000and saccharin were studied.These additives are found to reduce thegrain size,grain boundaries and improve surface morphology of the copper deposits.Also they improve the throwing power of thedepositing electrolytes and hardness of deposits.The electrodeposited copper coatings were characterized by X-ray diffractiontechnique.XRD results indicate that the electrodeposited copper shows polycrystalline and face centered cubic structure.The crystalsize was calculated by XRD and AFM analysis.Among these additives studied,the mixture of benzotriazole and sodium laurylsulphate acts as the best additive.A uniform pore-free surface observed under SEM and AFM results reveal the grain refining broughtabout by the additives.展开更多
The major solving ways for the material wear are surface modification and lubrication. Currently, the researches at home and abroad are all limited to the single study of either nano-lubricating oil additive or electr...The major solving ways for the material wear are surface modification and lubrication. Currently, the researches at home and abroad are all limited to the single study of either nano-lubricating oil additive or electroless deposited coating. The surface coating has high hardness and high wear resistance, however, the friction reduction performance of the coating with high hardness is not good, the thickness of the coating is limited, and the coating can not regenerate after wearing. The nano-lubricating additives have good tribological performance and self-repair function, but under heavy load, the self-repair rate to the worn surface with the nano-additives is smaller than the wearing rate of the friction pair. To solve the above problems, the Ni-W-P alloy coating and deposition process with excellent anti-wear, and suitable for industrial application were developed, the optimum bath composition and process can be obtained by studying the influence of the bath composition, temperature and PH value to the deposition rate and the plating solution stability. The tribological properties as well as anti-wear and friction reduction mechanism of wear self-repair nano-ceramic lubricating additives are also studied. The ring-block abrasion testing machine and energy dispersive spectrometer are used to explore the internal relation between the coating and the nano-lubricating oil additives, and the tribology mechanism, to seek the synergetic effect between the two. The test results show that the wear resistance of Ni-W-P alloy coating （with heat treatment and in oil with nano-ceramic additives） has increased hundreds times than 45 steel as the metal substrate in basic oil, the friction reduction performance is improved. This research breaks through the bottleneck of previous separate research of the above-mentioned two methods, and explores the combination use of the two methods in industrial field.展开更多
Background: The radiosensitizing effect of Photofrin II has been demonstrated in vitro and in animal models, even in tumor models known to be highly radioresistant, such as glioblastoma and bladder carcinoma. Radio-ad...Background: The radiosensitizing effect of Photofrin II has been demonstrated in vitro and in animal models, even in tumor models known to be highly radioresistant, such as glioblastoma and bladder carcinoma. Radio-adaptive doses are also known to lead to an augmented cell or tissue reaction. The aim of this study was to investigate potential synergistic or additive effects when combining the two methods in vitro for an improved therapeutic concept in bladder cancer. Material and Methods: RT4 human bladder carcinoma cell line and HCV29 human bladder epithelium cells were seeded and incubated with various concentrations of Photofrin II. The cells were additionally irradiated with ionizing radiation (0.05 Gy/2 Gy/0.05 Gy + 2 Gy). Cells without Photofrin II incubation and irradiation served as controls. The cell survival was evaluated. Results: The survival rate of both cell lines, RT4 and HCV29, did not differ significantly when incubated with a non-toxic concentration of Photofrin II and exposed to a pre-irradiation dose of 0.05 Gy prior to the 2 Gy radiation fraction, compared to cells exposed to Photofrin II plus a 2 Gy ionizing radiation. Conclusion: The combination of both methods did neither demonstrate a synergistic or additive effect nor did it lead to a negative influence of both modulating factors in an in vitro setting.展开更多
Fertilization or atmospheric deposition of nitrogen(N)and phosphorus(P)to terrestrial ecosystems can alter soil N(P)availability and the nature of nutrient limitation for plant growth.Changing the allocation of leaf P...Fertilization or atmospheric deposition of nitrogen(N)and phosphorus(P)to terrestrial ecosystems can alter soil N(P)availability and the nature of nutrient limitation for plant growth.Changing the allocation of leaf P fractions is potentially an adaptive strategy for plants to cope with soil N(P)availability and nutrient-limiting conditions.However,the impact of the interactions between imbalanced anthropogenic N and P inputs on the concentrations and allocation proportions of leaf P fractions in forest woody plants remains elusive.We conducted a metaanalysis of data about the concentrations and allocation proportions of leaf P fractions,specifically associated with individual and combined additions of N and P in evergreen forests,the dominant vegetation type in southern China where the primary productivity is usually considered limited by P.This assessment allowed us to quantitatively evaluate the effects of N and P additions alone and interactively on leaf P allocation and use strategies.Nitrogen addition(exacerbating P limitation)reduced the concentrations of leaf total P and different leaf P fractions.Nitrogen addition reduced the allocation to leaf metabolic P but increased the allocation to other fractions,while P addition showed opposite trends.The simultaneous additions of N and P showed an antagonistic(mutual suppression)effect on the concentrations of leaf P fractions,but an additive(summary)effect on the allocation proportions of leaf P fractions.These results highlight the importance of strategies of leaf P fraction allocation in forest plants under changes in environmental nutrient availability.Importantly,our study identified critical interactions associated with combined N and P inputs that affect leaf P fractions,thus aiding in predicting plant acclimation strategies in the context of intensifying and imbalanced anthropogenic nutrient inputs.展开更多
The synergistic damage effect of irradiation and corrosion of reactor structural materials has been a prominent research focus.This paper provides a comprehensive review of the synergistic effects on the third-and fou...The synergistic damage effect of irradiation and corrosion of reactor structural materials has been a prominent research focus.This paper provides a comprehensive review of the synergistic effects on the third-and fourth-generation fission nuclear energy structural materials used in pressurized water reactors and molten salt reactors.The competitive mechanisms of multiple influencing factors,such as the irradiation dose,corrosion type,and environmental temperature,are summarized in this paper.Conceptual approaches are proposed to alleviate the synergistic damage caused by irradiation and corrosion,thereby promoting in-depth research in the future and solving this key challenge for the structural materials used in reactors.展开更多
The catalytic behavior of a catalyst for chlorine-containing volatile organic compounds(CVOCs) oxidation largely depends on the synergistic interaction between the oxidizing and acidic sites.In the present work,two ca...The catalytic behavior of a catalyst for chlorine-containing volatile organic compounds(CVOCs) oxidation largely depends on the synergistic interaction between the oxidizing and acidic sites.In the present work,two catalysts with different distributions of CeO_(2) on the inner and outer surfaces of 4.0Ce-USY-ex and 4.0Ce-USY-dp(USY zeolite) were prepared respectively by ion exchange and deposition methods,with a purpose of finding out how the location of the oxidation sites(CeO_(2)) influence its synergistic effect with the acidic sites of zeolite.The results show that 4.0Ce-USY-ex is much more active for catalytic degradation of 1,2-dichloroethane(DCE),while 4.0Ce-USY-dp catalyst exhibit higher catalytic degradation activity for other structured CVOCs(dichloromethane(DCM),trichloroethylene(TCE),chlorobenzene(CB)).CeO_(2) in 4.0Ce-USY-ex catalyst mainly disperses in the pore channels of USY zeolite,and there are many strong acid centers on the surface,which is conducive to the dechlorination conversion of CVOCs.However,CeO_(2) in 4.0Ce-USY-dp catalyst is mainly distributed on the outer surface of USY and has strong oxidation ability,which contributes to the deep oxidation of CVOCs.Moreover,the presence of a large number of strong acid centers on the catalyst surface of 4.0Ce-USY-ex catalysts leads to severe accumulation of surface carbon species and significantly decreases its stability towards DCE.However,a large number of active oxygen species on the surface of 4.0Ce-USY-dp and CeO_(2) catalysts are beneficial to the deep oxidation of DCE,reducing the formation of surface carbon and thus improving the stability of the catalyst.Thus,the influence of the location of the oxidation sites on its synergistic effect with the acidic sites was established in the present work,which could provide some new ideas for the rational design of CVOCs degradation catalyst with appropriate distribution of active sites.展开更多
This study was aimed to analyze the effect of procyanidin B2(PC)and tannin acid(TA)on the activities of cholesterol esterase(CEase)and the inhibitory mechanisms of enzymatic activity.The interaction mechanisms were in...This study was aimed to analyze the effect of procyanidin B2(PC)and tannin acid(TA)on the activities of cholesterol esterase(CEase)and the inhibitory mechanisms of enzymatic activity.The interaction mechanisms were investigated by enzymatic kinetics,multi-spectroscopy methods,thermodynamics analysis,molecular docking,and dynamic simulations.PC and TA could bind with CEase and inhibit the activity of enzyme in a mixed-competitive manner and non-competitive manner,which was verified by molecular docking simulations and dynamics simulations.Also,PC and TA showed the synergistic inhibition with orlistat.Fluorescence,UVvis and the thermodynamic analysis revealed that the complexes were formed from CEase and inhibitors by noncovalent interaction.As revealed by the circular dichroism results,both PC and TA decreased enzymatic activities by altering the conformations of CEase.The inhibition of PC and TA on CEase might be one mechanism for its cholesterol-lowering effect.展开更多
BA_(2)(MA)_(n-1)Pb_nI_(3n+1)series low-dimensional(2D)perovskites have been widely investigated for their re markable environmental stability,but still suffer the poor light absorption and disordered phase distri buti...BA_(2)(MA)_(n-1)Pb_nI_(3n+1)series low-dimensional(2D)perovskites have been widely investigated for their re markable environmental stability,but still suffer the poor light absorption and disordered phase distri bution,hindering their practical applications.In this work,we combine the introduction of FA and the addition of PbCl_(2)to optimize the film quality,strengthen the light absorption,regulate internal phase distribution,and promote carrier transport inside 2D perovskite films.The incorporation of FA promote sufficient light absorption and improve the film crystallinity.Furthermore,the addition of Pb Cl_(2)elimi nates the low n phase(n=1)and suppresses the forming of the low n phase of n=2,enhancing the film conductivity and diminishing carrier recombination.The synergistic of A-site cation engineering and phase manipulation achieves a high efficiency of 16.48%.Importantly,the synergistic prepared perovskite film does not show any changes after 60 days in the air with an average humidity of 57%±3%,and the corresponding solar cell maintains 85%of the original efficiency after more than 800 h,demonstrating remarkable environmental stability.The results indicate that the synergistic of A-site cation engineering and phase manipulation is promising for producing superior efficiency,along with satisfying humidity stability.展开更多
Tetracycline(TC)as a typical emerging pollutant is becoming a serious threat to the environment and human health.A combined advanced oxidation technology of UV/Ozone(O_(3))/peroxydisulfate(PDS)process was developed to...Tetracycline(TC)as a typical emerging pollutant is becoming a serious threat to the environment and human health.A combined advanced oxidation technology of UV/Ozone(O_(3))/peroxydisulfate(PDS)process was developed to explore an efficient and economic treatment process of TC in wastewater.Furthermore,the reactive sites and transformation pathways of TC were explored and the toxicity of the intermediates was quantified with a quantitative structure-activity relationship(QSAR)assessment.The degradation performance of TC was substantially enhanced in UV/O_(3)/PDS process with a kobsof 0.0949 min-1,which was 2.3 times higher than UV/O_(3)and 3.2 times than sole UV.The results demonstrated that there was a superior synergistic effect of PDS on UV/O_(3)processes for the degradation of TC.Electron paramagnetic resonance(EPR)analysis and quenching experiments show that·OH,SO_(4)·-,O_(2)·-and1O_(2)all contributed to TC degradation in the UV/O_(3)/PDS process and exhibited a synergistic effect,which inhibited the generation of harmful products.In addition,the UV/O_(3)/PDS system can effectively degrade TC in a wide range of substrate concentrations and pH,and also showed excellent adaptability to various concentrations of anions(Cl-and HCO_(3)-).This study proves the feasibility of UV/O_(3)/PDS process for treating TC contaminated wastewater with complicated water matrix.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.22171122 and 22201123)Liaoning Revitalization Talents Program(No.XLYC 2007130)+1 种基金Fundamental Research Project(No.LJ212410148038)of the Educational Department of Liaoning ProvinceTalent Scientific Research Fund of Liaoning Petrochemical University(No.2016XJJL–019)。
文摘Attaining the selective oxidation of isochroman into isochromanone in a molecular oxygen(O_(2))environment without any additives,via a heterogeneous oxidation process,is highly desirable and challenging work.Herein,we prepare two mixed-addendum polyoxometalate-based coordination polymers of the general formula[H_(x)M_(1-x)(i-PrIm)_(4)][H_(2)N(CH_(3))_(2)]_(4)[HPMo_(8)V_(6)O_(42)](M=Co 1,Ni,2;i-PrIm=1-isopropyl-1H-imidazole).Needing no additives,they can catalyze the selective oxidation of isochroman to isochromanone with O_(2)as an oxidant,with yields of 91.5%(1)and 46.8%(2),respectively.Mechanistic studies indicate that the excellent performance of catalyst 1 is attributed to the synergistic operation of[Co(i-Pr-Im)_(4))]complex and PMo_(8)V_(6)unit,and that the catalytic reaction is a radical pathway involving superoxide radicals.Additionally,the catalyst 1 can be recycled and reused at least four times with uncompromised performance.These results provide fundamental guidelines for designing efficient and multi-site heterogeneous catalysts for the selective oxidation of benzyl C(sp^(3))-H bonds by activating O_(2).
基金National Natural Science Foundation of China(No.U2241231)National Key Research and Development Program of China(No.2021YFB3701100)+1 种基金Scientific Research Project of Jiangxi Provincial Department of Education,China(No.GJJ211038)Doctoral Research Project of Jinggangshan University,China(No.JZB2110)。
文摘The synergistic effect of low Gd+Mn additions on the evolution of microstructure and mechanical properties of Mg−xGd−0.8Mn alloy was investigated.Gd addition shows a strong grain refinement effect on the extruded Mg−xGd−0.8Mn alloy,and leads to a continuous decrease in the area fraction of basal texture grains and the corresponding maximum density of texture components.However,the maximum density of the basal texture components grows abruptly as Gd content increases to 6 wt.%.When the Gd content is below 6 wt.%,the asymmetry of the tensile and compressive yield of the alloy is negatively correlated to the Gd content due to grain refinement and texture weakening effects.Besides,the contribution of grain refinement to higher alloy yield strength is more significant than that of grain orientation.Compared with the extruded Mg−xGd alloy,the extruded Mg−xGd−0.8Mn alloy shows a lower limit composition point that corresponds to solid solution strengthening and plasticizing effect(2 wt.%and 4 wt.%).Finally,the trend of basal slip and prismatic slip resistance variations of the extruded Mg−xGd−0.8Mn alloys was predicted.
基金financially supported by the National Natural Science Foundation of China(No.21172269)the Fundamental Research Funds for the Central Universities,SouthCentral Minzu University(No.CZH24005)。
文摘Binuclear complexes have attracted extensive attention in fields such as catalysis because of their likely bimetallic synergistic effect;however,the mechanism and factors influencing this synergism remain unclear.In this work,six bis-β-ketoimine binuclear titanium complexes4a-4f containing different alkylthio sidearms and configurations were synthesized and characterized by nuclear magnetic resonance hydrogen spectrum(~1H-NMR),nuclear magnetic resonance carbon spectrum(^(13)C-NMR),Fourier transform infrared spectrum(FTIR),and elemental analysis.The intermetallic distances of isomeric complexes 4a,4d,4e and 4f determined through density functional theory(DFT)optimization were in the order 4a<4d<4e<4f and were found to significantly influence the catalytic performance for ethylene(co)polymerization.These complexes could efficiently catalyze ethylene polymerization and ethylene/1-hexene or ethylene/1-octene copolymerization with high activity to produce highmolecular-weight ethylene homo-and co-polymers.Among the three binuclear titanium complexes 4a-4c with similar structures but different lengths of alkylthio sidearms,complex 4a,which contained the shortest methylthio sidearm,exhibited the highest activity for ethylene polymerization and copolymerization with 1-hexene or 1-octene.Additionally,for ethylene/1-hexene or ethylene/1-octene copolymerization,it showed the highest comonomer incorporation compared with propylthio(4b)and octylthio(4c)derivatives because of the smaller steric hindrance of the methyl group in 4a and the more open coordination space for vinyl monomers.Furthermore,among the isomeric complexes 4a,4d,4e and4f,complex 4a with the shortest bimetallic distance also exhibited the highest activity towards ethylene(co)polymerization,and the highest 1-hexene or 1-octene incorporation in comparison with its regioisomeric counterparts 4d,4e and p-phenyl-bridged analog 4f,owing to a more appropriate bimetallic distance that is conducive to a synergistic effect.
基金supported by the National Natural Science Foun-dation of China(Grant Nos.12404228 and 52371148)the Science and Technology Research Program of Chongqing Ed-ucation Commission of China(Grant No.KJQN202200510).
文摘Bulk metallic glasses(BMGs)are typically characterized by high strength and elasticity.However,they generally demonstrate a deficiency in plastic deformation capability at room temperatures.In this work,Cu_(50-x)Zr_(46)Al4Agx(x=0,1,2,3,4)alloys were prepared by arc melting and copper mold casting to investigate their structure,glass-forming ability,and mechanical properties.The results show that the addition of Ag can increase the parameter of DTx and g in Cu_(50)Zr_(46)Al_(4)alloy by 116%and 1.5%respectively,effectively enhancing its thermal stability and glass-forming ability.Compressive fracture tests reveal that the addition of Ag can significantly improve the yield strength,ultimate strength,and plasticity of the Cu_(50)Zr_(46)Al_(4)alloy.Specifically,with the Ag addition of 1 at.%,the alloy’s ultimate strength and plasticity increased by 71.8%and 21 times,respectively.Furthermore,the introduction of Ag can effectively control the free volume content in the Cu_(50)Zr_(46)Al_(4)alloy,thereby tuning the hardness of the material.This work provides valuable insights into improving the mechanical performance of BMGs through micro-alloying approaches.
文摘The antioxidant and anti-wrinkle firming effects of a combination of vitamin C(Vc)and black Ganoderma lucidum extract was evaluted.Through the DPPH radical scavenging model and elastase inhibition model,this research investigates the impact of these substances individually and in combination on antioxidant capabilities and anti-wrinkle firming effects.The results demonstrate that the combination of Vc and black Ganoderma lucidum extract exhibits significant antioxidant abilities at various concentrations,and is more effective than when each is used separately,indicating a synergistic interaction between them.Additionally,the combination also shows significant inhibition of elastase,suggesting potential applications in delaying the aging process of the skin.Furthermore,highperformance liquid chromatography(HPLC)was used to determine if reactions occur among the components of the mixture.The findings reveal that the concentration of Vc in the mixture is very close to the theoretical concentration and relatively stable,suggesting that the components function independently.A quantitative analysis using the Bliss independence model further confirms the synergistic effects of Vc and black Ganoderma lucidum extract at specific ratios,providing a scientific basis for the development of efficacious cosmetic products.
基金supported by the Key Project of Tianjin Natural Science Foundation(No.23JCZDJC00570)Special Funding of China Postdoctoral Science Foundation(No.2023T160268)+3 种基金China Postdoctoral Science Foundation(No.2023M741362)the National natural science foundation of China(Nos.22276209 and 21822608)Research Center for Eco-Environmental Science(No.RCEES-TDZ-2021-7)the support from the Youth Innovation Promotion Association of CAS(No.Y2021019)。
文摘Electrocatalytic water splitting for hydrogen production is a key approach to tackling the current energy crisis.Among the catalysts,the traditional Pd@C catalysts are remarkable for their efficiency in hydrogen evolution.However,the high cost and scarcity of Pd catalysts,as well as the instability caused by the corrosiveness of carbon-based substrates,hinder their large-scale application.To overcome this challenge,an effective strategy is to construct highly dispersed Pd single atoms to improve palladium utilization and choose more stable materials as supports.In this study,TiO_(2-x)carriers with abundant oxygen vacancies were prepared and loaded with Pd by photoreduction deposition.Adjusting the palladium content resulted in three forms of Pd-loaded TiO_(2-x):nanoparticles(Pd@TiO_(2-x)(6%,10%)),nanoclusters(Pd@TiO_(2-x)(3%))and single atoms(Pd@TiO_(2-x)(1.5%)).The oxygen vacancies improved the stability of the titanium dioxide materials by providing more active hydrogen adsorption sites and increasing the affinity of Pd for active hydrogen.Single atom loading increased the frequency of oxygen holes in the support and the high activity of monatomic Pd promoted the adsorption of active hydrogen and facilitated the formation of active hydrogen intermediates.The synergistic effect of single atoms and oxygen vacancies improved the stability and catalytic activity of the composite material.Pd@TiO_(2-x)(1.5%)showed outstanding performance in hydrogen evolution in an acidic medium with an overpotential of only 24 m V at a current density of 10 m A/cm^(2)and a low Tafel rise of 41.9 m V/dec.This study provides an effective strategy for the development of high-performance hydrogen evolution(HER)catalysts.
基金financially supported by the National Science Foundation of China(62474142)Natural Science Foundation of Shandong Province(No.ZR2024YQ070)。
文摘Organic additives with multiple functional groups have shown great promise in improving the performance and stability of perovskite solar cells.The functional groups can passivate undercoordinated ions to reduce nonradiative recombination losses.However,how these groups synergistically affect the enhancement beyond passivation is still unclear.Specifically,isomeric molecules with different substitution patterns or molecular shapes remain elusive in designing new organic additives.Here,we report two isomeric carbazolyl bisphosphonate additives,2,7-Cz BP and 3,6-Cz BP.The isomerism effect on passivation and charge transport process was studied.The two molecules have similar passivation effects through multiple interactions,e.g.,P=O···Pb,P=O···H–N and N–H···I.2,7-CzBP can further bridge the perovskite crystallites to facilitates charge transport.Power conversion efficiencies(PCEs)of 25.88%and 21.04%were achieved for 0.09 cm^(2)devices and 14 cm^(2)modules after 2,7-Cz BP treatment,respectively.The devices exhibited enhanced operational stability maintaining 95%of initial PCE after 1000 h of continuous maximum power point tracking.This study of isomerism effect hints at the importance of tuning substitution positions and molecular shapes for organic additives,which paves the way for innovation of next-generation multifunctional aromatic additives.
基金supported by the National Natural Science Foundation of China(52473059)Taishan Scholar Constructive Engineering Foundation of Shandong Province(tsqn202103079)Key Research and Development Plan of Shandong Province(2024TSGC0264).
文摘Power cables are important pieces of equipment for energy transmission,but achieving a good balance between flame retardancy and mechanical properties of cable sheaths remains a challenge.In this work,a novel intumescent flame retardant(IFR)system containing silicone-containing macromolecular charring agent(Si-MCA)and ammonium polyphosphate(APP)was designed to synergistically improve the flame retardancy and mechanical properties of ethylene-butyl acrylate copolymer(EBA)composites.The optimal mass ratio of APP/Si-MCA was 3/1 in EBA composites(EBA/APP-Si-31),corresponding to the best flame retardancy with 31.2% of limited oxygen index(LOI),V-0 rating in UL-94 vertical burning test,and 76.4%reduction on the peak of heat release rate(PHRR)in cone calorimeter test.The enhancement mechanism was attributed to the synergistic effect of APP/Si-MCA during combustion,including the radical-trapping effect,the dilution effect of non-flammable gases,and the barrier effect of the intumescent char layer.Meanwhile,the tensile results indicated that EBA/APP-Si-31 also exhibited good mechanical properties with the addition of maleic anhydride-grafted polyethylene(PE-g-MA)as the compatibilizer.Thus,the APP/Si-MCA combination is an effective IFRs system for preparing high-performance EBA composites,and it will promote their applications as cable sheath materials.
基金funding from the National Natural Science Foundation of China(Nos.51991361 and 52288101)the Young Scientists Fund of the National Natural Science Foundation(No.52204023)。
文摘Ionic liquids(ILs),recognized for their negligible vapor pressure,thermal stability,and structural tailorability,offer targeted inhibition of clay expansion.Compared to ILs,polyionic liquids(PILs)possess stronger mechanical properties and adsorption capabilities,showing even greater potential in inhibiting clay swelling.In this work,we synthesized and characterized an imidazole-based ionic liquid(IL-NH_(2)),a polyionic liquid(PIL-ABHIm),and a PIL/IL combination.Their inhibitory performance was rigorously evaluated under simulated drilling conditions through immersion tests,linear swelling tests,among others.Additionally,the mechanisms underlying their interaction with clay minerals were elucidated through contact angle measurements,Fourier-transform infrared spectroscopy,X-ray diffraction(XRD),Zeta potential analysis,and molecular electrostatic potential(MEP)analysis.This work demonstrates that IL-NH_2inhibits osmotic hydration by altering the interlayer structure of the clay,while PIL-ABHIm reduces surface hydration by forming a hydrophobic barrier on the clay surface.PIL/IL combines both mechanisms,significantly enhancing the stability of clay through the dual mechanisms of cation exchange and hydrophobic barriers.These findings reveal an innovative mechanism by which PIL/IL combination inhibits clay hydration and swelling,providing a scientific foundation for their application in drilling fluids.
基金supported by the Major Fund Project of Anhui Province Department of Education(No.2022AH040077)the Academic Funding for Top Talents in Disciplines(Specialities)of Anhui Provincial High Education Institutes(No.gxbjzD2021056)the Program for New Era Cultivate Talents of Anhui province(Postgraduate Education)(No.2022xscx099).
文摘Ulcerative colitis(UC)is a chronic inflammatory disorder with a complex etiology,characterized by intestinal inflammation and barrier dysfunction.Platycodon grandiflorus polysaccharides(PGP),the primary component of Platycodon grandiflorus,and hesperidin(Hesp),a prominent active component in Citrus aurantium L.(CAL),have both demonstrated anti-inflammatory properties.This study aims to elucidate the underlying mechanism of the synergistic effect of PGP combined with Hesp on UC,focusing on the coordinated interaction between the phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT)and Janus kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3)signaling pathways.A mouse model of UC induced by dextran sulfate sodium(DSS)and a cell model using lipopolysaccharide(LPS)-induced RAW264.7/IEC6 cells were employed to investigate the in vitro and in vivo anti-inflammatory effects of PGP combined with Hesp on UC and its potential mechanism of action.The results indicated that compared to the effects of either drug alone,the combination of PGP and Hesp significantly modulated inflammatory factor levels,inhibited oxidative stress,regulated colonic mucosal immunity,suppressed apoptosis,and restored intestinal barrier function in vitro and in vivo.Further in vitro studies revealed that PGP significantly inhibited the PI3K/AKT signaling pathway,while Hesp significantly inhibited the JAK2/STAT3 signaling pathway.The use of inhibitors and activators targeting both pathways validated the synergistic effects of PGP combined with Hesp on the PI3K/AKT and JAK2/STAT3 signaling pathways.These findings suggest that PGP combined with Hesp exhibits a synergistic effect on DSS-induced colitis,potentially mediated through the phosphatase and tensin homolog(PTEN)/PI3K/AKT and interleukin-6(IL-6)/JAK2/STAT3 signaling pathways.
基金supported by National Natural Science Foundation of China(Nos.52472194,52101243)Natural Science Foundation of Guangdong Province,China(No.2023A1515012619)the Science and Technology Planning Project of Guangzhou(No.202201010565).
文摘Lithium-sulfur batteries(LSBs)are considered as the most promising energy storage technologies owing to their large theoretical energy density(2500Wh/kg)and specific capacity(1675 mAh/g).However,the heavy shuttle effect of polysulfides and the growth of lithium dendrites greatly hinder their further development and commercial application.In this paper,cobalt-molybdenum bimetallic carbides heterostructure(Co_(6)Mo_(6)C_(2)@Co@NC)was successfully prepared through chemical etching procedure of ZIF-67 precursor with sodium molybdate and the subsequent high temperature annealing process.The obtained dodecahedral Co_(6)Mo_(6)C_(2)@Co@NC with hollow and porous structure provides large specific surface area and plentiful active sites,which speeds up the chemisorption and catalytic conversion of polysulfides,thus mitigating the shuttle effect of polysulfides and the generation of lithium dendrites.When applied as the LSBs separator modifier layer,the cell with modified separator present excellent rate capability and durable cycling stability.In particular,the cell with Co_(6)Mo_(6)C_(2)@Co@NC/PP separator can maintain the high capacity of 738 mAh/g at the current density of 2 C and the specific capacity of 782.6 mAh/g after 300 cycles at 0.5 C,with the coulombic efficiency(CE)near to 100%.Moreover,the Co_(6)Mo_(6)C_(2)@Co@NC/PP battery exhibits the impressive capacity of 431 mAh/g in high sulfur loading(4.096 mg/cm^(2))at 0.5 C after 200 cycles.This work paves the way for the development of bimetallic carbides heterostructure multifunctional catalysts for durable Li-S battery applications and reveals the synergistic regulation of polysulfides and lithium dendrites through the optimization of the structure and composition.
文摘Electrodeposition of acid copper plating on mild steel substrate is tedious due to the galvanic displacement reaction ofcopper on mild steel.This can be avoided by using a proper complexing agent,because the complexing agent tuned the potential ofnoble direction to less noble direction by complex formation.In this paper,environment friendly electrodeposition of copper fromnon-cyanide electrolyte using sodium gluconate as complexing agent was investigated in alkaline medium.The effects of additivessuch as1,2,3-benzotriazole,sodium lauryl sulphate,PEG8000and saccharin were studied.These additives are found to reduce thegrain size,grain boundaries and improve surface morphology of the copper deposits.Also they improve the throwing power of thedepositing electrolytes and hardness of deposits.The electrodeposited copper coatings were characterized by X-ray diffractiontechnique.XRD results indicate that the electrodeposited copper shows polycrystalline and face centered cubic structure.The crystalsize was calculated by XRD and AFM analysis.Among these additives studied,the mixture of benzotriazole and sodium laurylsulphate acts as the best additive.A uniform pore-free surface observed under SEM and AFM results reveal the grain refining broughtabout by the additives.
文摘The major solving ways for the material wear are surface modification and lubrication. Currently, the researches at home and abroad are all limited to the single study of either nano-lubricating oil additive or electroless deposited coating. The surface coating has high hardness and high wear resistance, however, the friction reduction performance of the coating with high hardness is not good, the thickness of the coating is limited, and the coating can not regenerate after wearing. The nano-lubricating additives have good tribological performance and self-repair function, but under heavy load, the self-repair rate to the worn surface with the nano-additives is smaller than the wearing rate of the friction pair. To solve the above problems, the Ni-W-P alloy coating and deposition process with excellent anti-wear, and suitable for industrial application were developed, the optimum bath composition and process can be obtained by studying the influence of the bath composition, temperature and PH value to the deposition rate and the plating solution stability. The tribological properties as well as anti-wear and friction reduction mechanism of wear self-repair nano-ceramic lubricating additives are also studied. The ring-block abrasion testing machine and energy dispersive spectrometer are used to explore the internal relation between the coating and the nano-lubricating oil additives, and the tribology mechanism, to seek the synergetic effect between the two. The test results show that the wear resistance of Ni-W-P alloy coating （with heat treatment and in oil with nano-ceramic additives） has increased hundreds times than 45 steel as the metal substrate in basic oil, the friction reduction performance is improved. This research breaks through the bottleneck of previous separate research of the above-mentioned two methods, and explores the combination use of the two methods in industrial field.
文摘Background: The radiosensitizing effect of Photofrin II has been demonstrated in vitro and in animal models, even in tumor models known to be highly radioresistant, such as glioblastoma and bladder carcinoma. Radio-adaptive doses are also known to lead to an augmented cell or tissue reaction. The aim of this study was to investigate potential synergistic or additive effects when combining the two methods in vitro for an improved therapeutic concept in bladder cancer. Material and Methods: RT4 human bladder carcinoma cell line and HCV29 human bladder epithelium cells were seeded and incubated with various concentrations of Photofrin II. The cells were additionally irradiated with ionizing radiation (0.05 Gy/2 Gy/0.05 Gy + 2 Gy). Cells without Photofrin II incubation and irradiation served as controls. The cell survival was evaluated. Results: The survival rate of both cell lines, RT4 and HCV29, did not differ significantly when incubated with a non-toxic concentration of Photofrin II and exposed to a pre-irradiation dose of 0.05 Gy prior to the 2 Gy radiation fraction, compared to cells exposed to Photofrin II plus a 2 Gy ionizing radiation. Conclusion: The combination of both methods did neither demonstrate a synergistic or additive effect nor did it lead to a negative influence of both modulating factors in an in vitro setting.
基金supported by the National Natural Science Foundation of China(No.41473068)supported by China Postdoctoral Science Foundation(No.2022M722667)。
文摘Fertilization or atmospheric deposition of nitrogen(N)and phosphorus(P)to terrestrial ecosystems can alter soil N(P)availability and the nature of nutrient limitation for plant growth.Changing the allocation of leaf P fractions is potentially an adaptive strategy for plants to cope with soil N(P)availability and nutrient-limiting conditions.However,the impact of the interactions between imbalanced anthropogenic N and P inputs on the concentrations and allocation proportions of leaf P fractions in forest woody plants remains elusive.We conducted a metaanalysis of data about the concentrations and allocation proportions of leaf P fractions,specifically associated with individual and combined additions of N and P in evergreen forests,the dominant vegetation type in southern China where the primary productivity is usually considered limited by P.This assessment allowed us to quantitatively evaluate the effects of N and P additions alone and interactively on leaf P allocation and use strategies.Nitrogen addition(exacerbating P limitation)reduced the concentrations of leaf total P and different leaf P fractions.Nitrogen addition reduced the allocation to leaf metabolic P but increased the allocation to other fractions,while P addition showed opposite trends.The simultaneous additions of N and P showed an antagonistic(mutual suppression)effect on the concentrations of leaf P fractions,but an additive(summary)effect on the allocation proportions of leaf P fractions.These results highlight the importance of strategies of leaf P fraction allocation in forest plants under changes in environmental nutrient availability.Importantly,our study identified critical interactions associated with combined N and P inputs that affect leaf P fractions,thus aiding in predicting plant acclimation strategies in the context of intensifying and imbalanced anthropogenic nutrient inputs.
基金supported by the National Natural Science Foundation of China(Nos.12022515 and 11975304)the Youth Innovation Promotion Association,Chinese Academy of Sciences(No.Y202063)。
文摘The synergistic damage effect of irradiation and corrosion of reactor structural materials has been a prominent research focus.This paper provides a comprehensive review of the synergistic effects on the third-and fourth-generation fission nuclear energy structural materials used in pressurized water reactors and molten salt reactors.The competitive mechanisms of multiple influencing factors,such as the irradiation dose,corrosion type,and environmental temperature,are summarized in this paper.Conceptual approaches are proposed to alleviate the synergistic damage caused by irradiation and corrosion,thereby promoting in-depth research in the future and solving this key challenge for the structural materials used in reactors.
基金Project supported by the National Key Research and Development Program of China (2022YFB3504200)。
文摘The catalytic behavior of a catalyst for chlorine-containing volatile organic compounds(CVOCs) oxidation largely depends on the synergistic interaction between the oxidizing and acidic sites.In the present work,two catalysts with different distributions of CeO_(2) on the inner and outer surfaces of 4.0Ce-USY-ex and 4.0Ce-USY-dp(USY zeolite) were prepared respectively by ion exchange and deposition methods,with a purpose of finding out how the location of the oxidation sites(CeO_(2)) influence its synergistic effect with the acidic sites of zeolite.The results show that 4.0Ce-USY-ex is much more active for catalytic degradation of 1,2-dichloroethane(DCE),while 4.0Ce-USY-dp catalyst exhibit higher catalytic degradation activity for other structured CVOCs(dichloromethane(DCM),trichloroethylene(TCE),chlorobenzene(CB)).CeO_(2) in 4.0Ce-USY-ex catalyst mainly disperses in the pore channels of USY zeolite,and there are many strong acid centers on the surface,which is conducive to the dechlorination conversion of CVOCs.However,CeO_(2) in 4.0Ce-USY-dp catalyst is mainly distributed on the outer surface of USY and has strong oxidation ability,which contributes to the deep oxidation of CVOCs.Moreover,the presence of a large number of strong acid centers on the catalyst surface of 4.0Ce-USY-ex catalysts leads to severe accumulation of surface carbon species and significantly decreases its stability towards DCE.However,a large number of active oxygen species on the surface of 4.0Ce-USY-dp and CeO_(2) catalysts are beneficial to the deep oxidation of DCE,reducing the formation of surface carbon and thus improving the stability of the catalyst.Thus,the influence of the location of the oxidation sites on its synergistic effect with the acidic sites was established in the present work,which could provide some new ideas for the rational design of CVOCs degradation catalyst with appropriate distribution of active sites.
基金supported by the National Basic Research Program of China(‘973’program,2013CB127106)。
文摘This study was aimed to analyze the effect of procyanidin B2(PC)and tannin acid(TA)on the activities of cholesterol esterase(CEase)and the inhibitory mechanisms of enzymatic activity.The interaction mechanisms were investigated by enzymatic kinetics,multi-spectroscopy methods,thermodynamics analysis,molecular docking,and dynamic simulations.PC and TA could bind with CEase and inhibit the activity of enzyme in a mixed-competitive manner and non-competitive manner,which was verified by molecular docking simulations and dynamics simulations.Also,PC and TA showed the synergistic inhibition with orlistat.Fluorescence,UVvis and the thermodynamic analysis revealed that the complexes were formed from CEase and inhibitors by noncovalent interaction.As revealed by the circular dichroism results,both PC and TA decreased enzymatic activities by altering the conformations of CEase.The inhibition of PC and TA on CEase might be one mechanism for its cholesterol-lowering effect.
基金supported by the Chengdu Science and Technology Program(No.2021GH0200032HZ)Sichuan Engineering Technology Research Center of Basalt Fiber Composites Development and Application(No.2022SCXWYXWFC006)Natural Science Foundation of Sichuan Province(No.2022NSFSC0356)。
文摘BA_(2)(MA)_(n-1)Pb_nI_(3n+1)series low-dimensional(2D)perovskites have been widely investigated for their re markable environmental stability,but still suffer the poor light absorption and disordered phase distri bution,hindering their practical applications.In this work,we combine the introduction of FA and the addition of PbCl_(2)to optimize the film quality,strengthen the light absorption,regulate internal phase distribution,and promote carrier transport inside 2D perovskite films.The incorporation of FA promote sufficient light absorption and improve the film crystallinity.Furthermore,the addition of Pb Cl_(2)elimi nates the low n phase(n=1)and suppresses the forming of the low n phase of n=2,enhancing the film conductivity and diminishing carrier recombination.The synergistic of A-site cation engineering and phase manipulation achieves a high efficiency of 16.48%.Importantly,the synergistic prepared perovskite film does not show any changes after 60 days in the air with an average humidity of 57%±3%,and the corresponding solar cell maintains 85%of the original efficiency after more than 800 h,demonstrating remarkable environmental stability.The results indicate that the synergistic of A-site cation engineering and phase manipulation is promising for producing superior efficiency,along with satisfying humidity stability.
基金financial support from the National Natural Foundation of China(Nos.52370045 and 51838009)Natural Science Foundation of Shanghai(No.23ZR1467500),and Shanghai Rising-Star Program(No.20QC1400300)。
文摘Tetracycline(TC)as a typical emerging pollutant is becoming a serious threat to the environment and human health.A combined advanced oxidation technology of UV/Ozone(O_(3))/peroxydisulfate(PDS)process was developed to explore an efficient and economic treatment process of TC in wastewater.Furthermore,the reactive sites and transformation pathways of TC were explored and the toxicity of the intermediates was quantified with a quantitative structure-activity relationship(QSAR)assessment.The degradation performance of TC was substantially enhanced in UV/O_(3)/PDS process with a kobsof 0.0949 min-1,which was 2.3 times higher than UV/O_(3)and 3.2 times than sole UV.The results demonstrated that there was a superior synergistic effect of PDS on UV/O_(3)processes for the degradation of TC.Electron paramagnetic resonance(EPR)analysis and quenching experiments show that·OH,SO_(4)·-,O_(2)·-and1O_(2)all contributed to TC degradation in the UV/O_(3)/PDS process and exhibited a synergistic effect,which inhibited the generation of harmful products.In addition,the UV/O_(3)/PDS system can effectively degrade TC in a wide range of substrate concentrations and pH,and also showed excellent adaptability to various concentrations of anions(Cl-and HCO_(3)-).This study proves the feasibility of UV/O_(3)/PDS process for treating TC contaminated wastewater with complicated water matrix.
